bt - ‘ees ‘ .7 iy mu) Pilla DA * + oh eon he ee Tee. r , a -" a y - s vel ve PED ANNUAL REPORT OF THE BOARD OF REGENTS OF THE SMITHSONIAN INSTITUTION SHOWING THE OPERATIONS, EXPENDITURES AND CONDITION OF THE INSTITUTION FOR THE YEAR ENDING JUNE 30 1908 WASHINGTON GOVERNMENT PRINTING OFFICE 1909 AB yd had No FROM THE SECRETARY OF THE SMITHSONIAN INSTITUTION, ACCOMPANYING The Annual Report of the Board of Regents of the Institution for the year ending June 30, 1908. SMITHSONIAN INstTITUTION, Washington, June 12, 1909. To the Congress of the United States: In accordance with section 5593 of the Revised Statutes of the United States, I have the honor, in behalf of the Board of Regents, to submit to Congress the Annual Report of the operations, expendi- tures, and condition of the Smithsonian Institution for the year ending June 30, 1908. I have the honor to be, very respectfully, your obedient servant, Cuartes D. Watcort, Secretary. Tit ANNUAL REPORT OF THE SMITHSONIAN INSTITUTION FOR THE YEAR ENDING JUNE 30, 1908. SUBJECTS. 1. Annual report of the secretary, giving an account of the opera- tions and condition of the Institution for the year ending June 30, 1908, with statistics of exchanges, ete. 2. Report of the executive committee, exhibiting the financial affairs of the Institution, including a statement of the Smithson fund, and receipts and expenditures for the year ending June 30, 1908. 3. Proceedings of the Board of Regents for the sessions of Decem- ber 3, 1907, and January 22 and February 12, 1908. 4, General appendix, comprising a selection of miscellaneous mem- oirs of interest to collaborators and correspondents of the Institution, teachers, and others engaged in the promotion of knowledge. These memoirs relate chiefly to the calendar year 1908. IV CONTENTS. Letter from the Secretary submitting the Annual Report of the Regents ae 40)» OKOYB MERCIA a a eo a Il Generalgsubyectsio£ thevannualbneportie = ee a IV CONTENTS MO fast kT ClO Ieee ee ees ee eee oe ee Ve Vv TLSHBe OP [SD RES es Een Nee OR cl cl ee 7 | Omer SsoLeihepinstiiunoOnsandsits) bran Chegmes == a= soe ee Ix REPORT OF THE SECRETARY. PIRES ep SiN CASO ea es TNS Eel gM tal Ya s eS 1 CY ayg) « TEES 2 CUTS aS 0 a a SB oS re ail hey BOaArdvoEwves emt Sa ee ee ee eee NE Dd ee er al PNG WaT CWS) MeN aN See ee al ee ee ee eee Pe J ENUM ES a i a 4 Explorations and researches: Studies in Cambrian geology and paleontology_________________ 7 JACTEM UA ME AES e HG) Oe OE eee oe 8 Meteor crater of Canyon Diablo, Arizona_____________ 9 PAU AS ceil X10 CCGG © Mien tere eee ee we Td oe Be eee 10 Ceolosyaohethe sally sss ee ere es LE eee eee 10 Absohitegmedsurement Of sound.) ee ee ial RecA CUlAtOnV OLA LONG WelchtsSes. = 9a ee ca ea 11 Properties of matter at temperature of liquid air__-__-________ 11 Boranicaleresenrchesi in) (Calitornig e222 se os ee ae 11 Deep-welleiemperatwresj =e = ee ee ee ee a oe 12 Investigations under the Hodgkins fund: Hodgkins fund prize for essay on tuberculosis_________________ 12 Flow of air at high pressure through a nozzle_________________ 13 Studyvot the supper atmospheres. == 2 sk 14 ANTES CSm Olan Gale COMM. soe seen eee ee 14 Mechanicssotethemenrihss atmospheres. ee ee 15 Smithsonian table at Naples Zoological Station____________________ ally VEEL DUS TIO) OS Sa a ee eee 17% Advisory committee on printing and publication_____________ Zit DY OV) El Oya OS eS ye a ae Se SI cee a ED 21 Preservation of archeological sites________ HP yt 3 er A eg este 22 CasaGrandewrwinen nM: pAriZOMaa- = ea. 8 eer ee Se ee 5 MeSH ViErd ereN ait Om alle bent Keep eee ee See Oe oy ie Uk 23 CWOLTESWOMG Git c er memene ee ee et creer kre Oem eee a ee 24 Coneressesman dice] Corel tO iste emer eee Se 24 DSSS Exe UES MSY OS WS = eS a a et a ee ee 26 DNV EENO MONT he WM CTS TENG Ne I 27 INationalleG alll eriyar@ fe cAn ie ee eee Oe 28 BUCA UnOheAm ericame hth O10 Gy 2. ae ee ee ee ee 29 Me EMA On alles CMAN SCG jase = eee ee Se i a ee 30 aon ee AOOLO Stele ai keene ee bee ee 32 AASTHROIOLON SICAL OOS Oe Se I ee ee 33 Internationals Catalosueror Scientific) literatures. =2 == 3 =) see 34 VI “CONTENTS. Page. Appendix I. Report on the United States National Museum_____-_-____- 36 II. Report on the Bureau of American Ethnology____-------__- 44 Ii. Report on the International> Exchanges —--__ === === === === 53 IV. Report on the National Zoological Park-----_____________--~ 62 VY. Report on the Astrophysical Observatory.__--—-_-_--_-_____ 68 VWiesenortioneihe dul bTay= =) ea ea eee ee eee 73 VII. Report on the International Catalogue of Scientific Literature_ 77 Vai RenoEtsonstnen publica GiOns2 ee — as as ae eee 79 REPORT OF THE EXECUTIVE COMMITTEE. PANCEION OL iMe nuns tly, Wh" 90S se22= secs eaeneace saci bemacecosices eons 87 Receipts and disbursements, July 1, 1907, to June 30, 1908 -.........-------- 88 pummary OF appropriavions by Coneress-2 sos. -0saseccsecceecenastacscee 90 PROCEEDINGS OF BOARD OF REGENTS. Meetings of December 3, 1907, January 22 and February 12, 1908....-.....--- 92 ACTS AND RESOLUTIONS OF CONGRESS. Acts of Sixtieth Congress, first session, relative to Smithsonian Institution and TRPSLTCTRTI EY Gd gC eRe apes ey RL Rep gs a SIE py a Sn A ae eS 102 GENERAL APPENDIX. The present status of military aeronautics, by Maj. George O. Squier, U.S.A. 117 Aviation in France in 1908, by Pierre-Roger Jourdain ..........-2.-.----.-- 145 Mirciess telophony, .by RK: A. Fessenden: 22:2. 2s-.ccsccceeeesoceceecacce 161 Muowrelepraphy, by ElenricArmagnat.. 2245082 252 cc Jactiserececiose cack See 197 The gramophone and the mechanical recording and reproduction of musical Pema by evel Ni eddie aot kee ten sts Nl 5 Ian een ane 209 On the light thrown by recent investigations on electricity on the relation be- meen matter and ether: by J.) Ji: Thomson’ =. 522.22 225 42eesc ene eee 234 Development of general and physical chemistry during the last forty years, by ENCES fos pts ik hen eee CR een ae 2 AER a eae Rh 245 Development of technological chemistry during the last forty years, by O. N. ABE NG ee ae eR A mtg eo AE REINS + TE Rc aN ny PONE a 255 Twenty years’ progress in explosives, by Oscar Guttmann...............___.. 263 Recent researches in the structure of the universe, by J. C. Kapteyn......_.- 301 Solar vortices and magnetism in sun spots, by C. G. Abbot..........-..._..- 321 Climatic variations: their extent and causes, by J. W. Gregory......-....--- 339 Pramumsand. peolopy: ‘hy Joba Joly= 2-2. << sss5.. eu se eee ocx a ee ee 355 An outline review of the geology of Peru, by George I. Adams ...._.-_- ea ee 385 Our present knowledge of the earth, by E. Wiechert ............- Soe Sore 431 The antarctic question— Voyages since 1898, by J. Machat................... 451 Some geographical aspects of the Nile, by Capt. H. G. Lyons...........-.-.. 481 Heredity, and the origin of species, by Daniel Trembly MacDougalee 2. 2 2ee 505 Cactaceze of northeastern and central Mexico, together with a synopsis of the principal Mexican genera, by William Edwin Safford..................... 525 Angler fishes: their kinds and ways, by Theodore Gill..____............... 565 Ene pIros er india, by Douglas Dewar. ooo nues. oon scant cece eccces eee. 617 The evolution of the elephant, by Richard 8. Lull.......................... 641 Excavations at Boghaz-Keuiin thesummer of 1907, by Hugo Winckler and 0. POUR PEIT toss oo ee aw Sie ee A eT Ee Ee yee Sy ee ee ee a 67 @rousriain Greece, by Ronald Rors\2. 625.2. -2-an-eucc en ecu ceo 697 Carl von Linné as a geologist, by A. G. Nathorst ........................... Tl Life and work of Lord Kelvin, by Silvanus P. ROM pots core sateen eo aoe 745 LIST OF MILITARY AERONAUTICS (Squier) : Plates Plates Plates 5 Plates 7 Plates late SrER20\ 2 a a eS Plates WIRELESS den) : TELEPHONY (TI essen- Pigties a2 soa S. See ele PATS RA elon ea pes oy Plates 6-4 Plates 12h EW r(eks 8 Mts ree Plates THE GRAMOPHONE (Reddie) : CDV aU eel iE le ee Wlatem2 ee ses tee Oe eee be PROGRESS IN EXPLOSIVES (Gutt- mann): Plates 1 Pate Swe aa ek es re eee Plates 5 Plates 7 Bat eR Oates ee Se at SOLAR VORTICES AND MAGNETISM IN SuN Sports (Abbot) : TAOS will) ea cht ae ae ee TAGS eee a is a eed TOS Ae by sales 2 at ie he URANIUM AND GEOLOGY (Joly) : late alka ek 68 ee BS GEOLOGY oF PERU (Adams) : Plates 1-5 PLATES. ANTARCTIC QUESTION (Machat) : (eae tele ones fal Se GEOGRAPHICAL ASPECTS OF NILE (Lyons) : Plates 1, 2 Plates 3, 4 HEREDITY AND ORIGIN OF SPECIES (MacDougal) : Plate 1 CACTACEZ OF Mexico (Safford) : 2G We a ee as ee TA Cte ete ea Os Set a PAROS 3 Annee Plates ie Gees 08d ane PIAS aia rote ee Pee Plate O Rha mieael ag nee Pate Saal 2 elise See PAAtES Ae iy Soe eS aes EVOLUTION OF ELEPHANT (Lull): EXCAVATIONS IN BOGHAZ-IKQrUI (Winckler and Puchstein) : Tarte eles Seette 28 ee ee ACS igh pa ser te eee 2 BlatessG—O rsa Ses ee IESE ait pil (ee ae ee ee ee 2 THE KELVIN (Thomp- son): 1 BPI tel gs eee eae a a eA WorK oF HENRI (Broca) : lente vel eee ceh eee eS LECTURE BECQUEREL THE SMITHSONIAN INSTITUTION. JUNE 30, 1908. Presiding officer ex officio—THroDORE ROOSEVELT, President of the United States. Chancellor.—MELVILLE W. FULLER, Chief Justice of the United States. Members of the Institution: THEODORE ROOSEVELT, President of the United States. CHARLES W. FAIRBANKS, Vice-President of the United States. MELVILLE W. Futter, Chief Justice of the United States. Eiinv Root, Secretary of State. GEORGE B. CorTELYOU, Secretary of the Treasury. WitiiaAmM H. Tart, Secretary of War.. CHARLES J. BONAPARTE, Attorney-General. GEORGE VON L. MEYER, Postmaster-General. Victor H. METCALF, Secretary of the Navy. JAMES R, GARFIELD, Secretary of the Interior. JAMES WILSON, Secretary of Agriculture. OscarR 8S. STRAUS, Secretary of Commerce and Labor. Regents of the Institution: MELVILLE W. Futter, Chief Justice of the United States, Chancellor. CHARLES W. FAIRBANKS, Vice-President of the United States. SHELBY M. CuLtom, Member of the Senate. Henry Casor Lopcr, Member of the Senate. A. O. Bacon, Member of the Senate. JOHN DaALzeLL, Member of the House of Representatives. JAMES R. MAnn, Member of the House of Representatives. WILLIAM M. Howarp, Member of the House of Representatives. JAMES B. ANGELL, citizen of Michigan. ANDREW D. WHITE, citizen of New York. JOHN B. HENDERSON, citizen of Washington, D. C. ALEXANDER GRAHAM BELL, citizen of Washington, D. C. GEORGE GRAY, citizen of Delaware. CHARLES F. CHOATE, Jr., citizen of Massachusetts. Executive Committee —J. B. HENDERSON, ALEXANDER GRAHAM BELL, DALZELL, Secretary of the Institution—CHARLES D. WALCOTT. Assistant Secretaries.—RicHARD RATHBUN; CyRUS ADLER. Chief Clerk.—HARRY W. DORSEY. Accountant and Disbursing Agent.—W. I. ADAMS. Editor.—A, Howarpb CLARK. Ix JOHN x THE SMITHSONIAN INSTITUTION. NATIONAL MUSEUM. Assistant Secretary in Charge.—RicHARD RATHBUN. Administrative Assistant—W. DE C. RAVENEL. Head Curators.—F. W. TRUE, G. P. MERRILL, OTIS T. MASON. Curators.—Cyrus ADLER, Ray S. Basster, A. Howarp CLARK, F. V. COVILLE, W. H. Datt, B. W. Evermann, J. M. Fuint, U. S. N. (retired), W. ET; Hoimes, L. O. Howarp, RicHarD RATHBUN, Ropert Ripeway, LEONHARD STEJNEGER, CHARLES D. WALCOTT. Associate Curators.—J. N. Rosr, DAvID WHITE. Curator, National Gallery of Art.—W. H. HoLMEs. Chief of Correspondence and Documents.—RANDOLPH I. GEARE. Superiniendent of Construction and Labor.—J. 8S. GOLDSMITH. Editor.—Marcus BENJAMIN. Photographer.—T. W. SMILLIE. Registrar._S. C. Brown. BUREAU OR AMERICAN ETHNOLOGY. Chief—W. H. HOLMES. Ethnologists—J. WALTER Frewkes, J. N. B. Hewitt, F. W. Hopcr, JAMES Mooney, MatitpA Coxe STEVENSON, JOHN R. SWANTON, Cyrus THOMAS. Philologist.—FRANZ Boas. Tllustrator.—Dr LANCEY W. GILL. INTERNATIONAL EXCHANGES. | Assistant Secretary in Charge.—CyrRus ADLER. Chief Clerk.—k. V. BERRY. NATIONAL ZOOLOGICAL PARK. Superintendent.—F RANK BAKER, Assistant Superintendent.—A. B. BAKER. ASTROPHYSICAL OBSERVATORY. Director.—C. G. ABBOT. Aid.—F. E. Fowte, Jr. BUREAU OF INTERNATIONAL CATALOGUE OF SCIENTIFIC LITERATURE. Assistant Secretary in Charge.-—Cyrus ADLER. Chief Assistant.—L. C. GUNNELL, REPORT OF THE SECRETARY OF THE SMITHSONIAN INSTITUTION, CHARLES D. WALCOTT, FOR THE YEAR ENDING JUNE 30, 1908, To the Board of Regents of the Smithsonian Institution: GENTLEMEN: I have the honor to submit a report showing the oper- ations of the Institution during the year ending June 30, 1908, including the work placed under its direction by Congress in the United States National Museum, the Bureau of American Ethnology, the International Exchanges, the National Zoological Park, the Astro- physical Observatory, the regional bureau of the International Catalogue of Scientific Literature, and the excavations on the Casa Grande Reservation. In the body of this report there is given a general account of the affairs of the Institution, while the appendix presents a more detailed statement by those in direct charge of the different branches of the work. Independently of this the operations of the National Museum and the Bureau of American Ethnology are fully treated in separate volumes. The scientific work of the Astrophysical Observatory, covering its researches for five years, is described in Volume IT of the Annals of the Observatory, published during the year. THE SMITHSONIAN INSTITUTION. THE ESTABLISHMENT. By act of Congress approved August 10, 1846, the Smithsonian Institution was created an establishment. Its statutory members are “the President, the Vice-President, the Chief Justice, and the heads of the executive departments.” THE BOARD OF REGENTS. The Board of Regents consists of the Vice-President and the Chief Justice of the United States as ex-officio members, three members of the Senate, three Members of the House of Representatives, and six 2 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. citizens, “ two of whom shall be residents of the city of Washington, and the other four shall be inhabitants of some State, but no two of them of the same State.” It is with regret that I have to record the resignation of the Hon. Richard Olney on January 20, 1908. Mr. Olney served on the Board of Regents as a citizen of Massachusetts for eight years. The following appointments and reappointments of Regents were made during the year: By appointment of the Speaker, December 9, 1907, Representatives John Dalzell, James R. Mann, and William M. Howard, to succeed themselves; by appointment of the President of the Senate on January 14, 1908, Senator Augustus O. Bacon to succeed himself; by joint resolution of Congress approved F ebruary 24, 1908, the Hon. Charles F. Choate, jr., 2 Massachusetts, 1 in place of the Hon. Richard Olney, resigned. The board met on December 3, 1907, January 22, 1908, and Febru- ary 12, 1908. The proceedings of Hees meetings will be printed as customary in the annual report of the board to Congress. ADMINISTRATION. With the aid rendered by the several experienced and efficient staffs the administrative work of the Institution and the several branches of the government service committed to its care has pro- gressed in a satisfactory manner during the year. The affairs of the Institution have received prompt administrative consideration, and a united effort has been made to carry out vigorously and conscien- tiously the fundamental purposes of the Institution, “the increase and diffusion of knowledge.” Under the general supervision of the Secretary the extended and complicated operations of the National Museum have been efficiently managed by the assistant secretary in charge of ~the National Museum, Mr. Richard Rathbun. Dr. Cyrus Adler, assistant secre- tary in charge of library and exchanges, has also rendered important service in connection with the regional bureau of the International Catalogue of Scientific Literature and in the general business of the Institution. The affairs of the Bureau of American Ethnology have continued in charge of Mr. W. H. Holmes, Mr. C. G. Abbot has advanced the work of the Astrophysical Observatory, and Dr. Frank Baker has superintended the administration of the National Zoological Park. The Secretary has availed himself of the assistance of the officers in charge of the various branches and conferred freely with them during the year. Certain changes in the routine of business in the Institution proper and in the several branches have been approved upon recommendation of the committee on business methods. REPORT OF THE SECRETARY. 3 The routine work of the Institution proper and of the several branches of the government service under its direction was examined in detail during the year, including the methods of correspondence, the handling of freight, the purchase and issuance of property and supphes, the distribution of publications, the receipt and disburse- ment of moneys, and rules and regulations affecting leaves of absence and other matters relating to the personnel. In order that the most modern advances in office methods might be applied to the Institution where necessary, a subcommittee of the committee on business methods was directed to visit the executive departments and local commercial establishments, and the report of this subcommittee was of material assistance in suggesting needed modifications in the transaction of routine business under the Institution. Among the most important improvements in this direction were certain changes in the accession- ing of material received by the National Museum for examination and report. The general effect of the recommendations of the com- mittee has been to reduce the amount of work and to facilitate the dispatch of business. The advisory committee on printing and publication, appointed in pursuance of executive order of January 20, 1906, which com- mittee is composed of representatives from the Institution and its branches, has rendered valuable assistance in scrutinizing manu- scripts proposed for publication and blank forms used in the work of the Institution and its branches. Appointments to the staffs of the National Museum, the Inter- national Exchanges, the Bureau of American Ethnology, the National ° Zoological Park, the Astrophysical Observatory, and the regional bureau of the International Catalogue of Scientific Literature have been made from time to time as vacancies occurred, in accordance with the civil-service rules and requirements; these establishments, with the exception of the last named, having been placed under the operation of the civil-service law on June 30, 1896, the International Catalogue having later been subjected to the jurisdiction of the com- mission. No important changes have been made in the routine affecting appointments, except that by executive orders the rules were modified to permit transfers of persons serving for a period of six months ending within one year from the date of proposed transfer, and the requirements of examination were allowed to be waived in the discretion of the Civil Service Commission. The privilege of making emergency appointments, pending the permanent appoint- ment of eligibles through certification, was discontinued, likewise by executive order, and all temporary appointments are required now to be approved in advance by the commission. Such appointments are no longer limited arbitrarily to six months, but may, under cer- tain circumstances, be extended beyond that term. Recommendations 4 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. of appointing officers affecting the method of appointment to posi- tions in the classified service are, by executive order of February 20, 1908, required to be forwarded, with a full statement of the reasons therefor, through the Civil Service Commission, to the President. The current business of the Institution has been conducted in a prompt and effective manner, and it is gratifying to note that no arrearages in the work of the government branches under its direc- tion were necessary to be reported in the quarterly statements to the President and in the annual statement which, in accordance with law, accompanied the estimates transmitted to Congress. FINANCES. The permanent fund of the Institution and the sources from which it was derived are as follows: Deposited in the Treasury of the United States. Begiuestwolismithsons WS4Gs ee oo. ee ee ee ee $515, 169. 00 ReENduaryecaCyIOL SNILENSON, slSOte= === = ae ans oe ee 26, 210. 63 WEHOSIL LOM Savings Ob INCOME I SOt == eee 108, 620. 3 Bequest of James Hamilton, WSio2=- 2-3 2 $1, 000. 00 Accumulated interest on Hamilton fund, 1895__________ 1, 000. 00 ——_——— 2, 000. 00 BeEquestnore Simeon Habel, 1 S808. lass ee eee 500. 00 Deposit from proceeds of sale of bonds, 1881_.+__________________ 51, 500. 00 GitiwOhennomaseG. ELOd2Icin Saal Olle = aw ee eee 200, 000. 00 Part of residuary legacy of Thomas G. Hodgkins, 1894___________ 8, 000. 00 DEPOSI rOMesaAyIn eS Of income 190322 ae eae ee ee 25, 000. 00 Residuary legacy of Thomas G. Hodgkins_____________--_-_______ 7, 918. 69 Total amount of fund in the United States Treasury_______ 944, 918. 69 Held at the Smithsonian Institution. Registered and guaranteed bonds of the West Shore Railroad Com- pany (par value), part of legacy of Thomas G. Hodgkins_______ 42, 000. 00 Mora permanente tundas=2-e ee a eee = apes 986, 918. 69 That part of the fund deposited in the Treasury of the United States bears interest at 6 per cent per annum, under the provisions of the act organizing the Institution and an act of Congress approved March 12, 1894. The rate of interest on the West Shore Railroad bonds is 4 per cent per annum. The income of the Institution during the year, amounting to $63,372.96, was derived as follows: Interest on the permanent fund, $58,262.52; proceeds from claims in litigation, $300, and from mis- cellaneous sources, $4,810.44; all of which was deposited in the Treas- ury of the United States to the credit of the current account of the Institution, REPORT OF THE SECRETARY. 5 With the balance of $24,592.01 on July 1, 1907, the total resources for the fiscal year amounted to $87,964.97. The disbursements, which are given in detail in the annual report of the executive committee, amounted to $69,198.56, leaving a balance of $18,766.41 on deposit June 30, 1908, in the United States Treasury. The Institution was charged by Congress with the disbursement of the following appropriations for the year ending June 30, 1908: IMtern a ton aieet xehan Ses 22 aati Se oe ee eee ee Pewee eS OU PACTNY GT Gea Tm Us ETC] 0) yet le es CO ee See de 40, 000 ySNISHETECO) OY a 7SAU CEE (Q) SSN EN EEN 5 0 Cte a aS sp ye eM 13, 000 National Museum: DESO RS NITH GST TS Css eNO TGS TOIT Si en a 20, 000 Featingnan Olio ht ime a eee RYE IES aL ok he 18, 000 Preservation of collections__________--_ fas Pa Apne ester WA cae 190, 000 J ERGO SS eee i el a ee ne 2, 000 VEX OKS EE Eg oY 2 RT a gE Pe ee et 500 FLeNtpeOL mWOLKSNOp Sas ee me eee ee ae ee Ta ee eRe als OS, a TE F 4, 580 TSS eT KO THTaVeS TREY OR ISS fe a a ee 15, 000 IND Ona AOOLOSiCalle ean ke = = ss Os Ee ee eee eae AO OOO International Catalogue of Scientific Literature__________________-_ 5, 000 Protection and excavation, ruin of Casa Grande, Arizona___________ 3, 000 iNew DULldine tor sNationall Minseuim sees os es eee eee 1, 250, 000 CUES EEN) | Sse at eae SG RN a ee ee ee ere ee 1, 703, OSO Estimates.—The estimates forwarded to Congress in behalf of the Government branches of the Institution and the appropriations based thereon for the fiscal year ending June 30, 1909, are as follows: Estimates. ppUOuTes HaTen ALON Alb CHANGES oem eee a4 saeco coe sm hase ce aa cee soem nev eer ations $32, 000 $32, 000 AMO Cane unin OLO Mess sea ne eee ees at a aee seis cackisceree ote ccs oancseee oes 52, 000 42, 000 Reimbursement Ota ell dc7COze ae saecrcieceroceoeenenitocecee ses cer sseeee scree O2D ile wsiercesstcoese Astrophysical O DSCEV ALON: wc stents ese n= wacisl sc aiae <\eleisieieicie sie stele ctniesloceisige swicis = 20, 000 13, 000 National Museum: Maciivumenat Gutx hres tesserae seias eee cee sel sam niseine ee nee seems eis ase Sele = 2200, 000 50, 000 Het hineanaliehtinss seo sts nce = obe clases sees ee cio ea caese ae seeine 25, 000 22, 000 PreservawonloLlcollectiOnsy=--po= see eee ee soe sos see aeons aacemoavees oss 190, 000 190, 000 BOOKS eae sete nc oa ere ele a ee ae eae eee we cate tecks see eesctwecbecics 2,000 2, 000 PEER Se oe re oS EE ra tiey ea Ned hit ke oe ie eas 500 | 500 RCH OL WOLKSNOpSaateo ete sees ae ae oe cee eaeee a Ac inn sae ise oe Sema s ce see 4,580 | 4,580 BUG SNC PAIES ee cen ewe eee pecciys cst ae ceases acecisiacleceaetiococessicee ce 15, 000 15, 000 Nations ueallenvwiol Arter ee sees saree sac catse cere anak cisoseesseccesuesceles GOOCON |S -eecaesacas NeutionaliZoolopicaleParkces car cose can cent sacs secen lec tbe Somes ee cmoesnceccues 110, 000 | 95, 000 Readjustment of DOUNGaATIeS eet see cee resem eee seein sles mic wie teens cies < 40K 000A ies Semcon International Catalogue of Scientific Literature ..............-----.---------+ 5, 000 5, 000 TCSII Ry ar Oe ea eR A ae eee a 2 ae | 756, 605 471, 080 | “Owing to delay in completion of the new National Museum building the request was made before the Appropriations Committee that $50,000 be appropriated under this item, which was done, 6 ANNUAL REPORT SMi#THSONIAN INSTITUTION, 1908. One of the important questions that comes up for consideration annually is that of submitting estimates to the Congress for the sup- port of the several branches placed by the Congress under the adminis- trative charges of the Smithsonian Institution. As the executive offi- cer of the Institution it is my duty to give careful consideration to the administration of the federal branches under its charge and to ascer- tain as far as possible the needs of each branch, and to see that the conclusions are clearly formulated in the estimates and later pre- sented orally or in printing as the committees in the Congress may desire. In considering estimates there is necessarily a decided difference in the point of view of the administrative officers in charge of the sev- eral branches of the Institution and the members of the congres- sional appropriation committees. The former see clearly what in their judgment is needed to make the particular work or department in their charge effective and a credit to the American people who own and sustain it. The members of the committee have a general idea of the character of the work being done and its relative importance in comparison with similar work elsewhere, and time is taken for hearings and consideration of individual objects. In deciding on the amount to be appropriated the committee has also in mind the present and prospective condition of the Treasury, the total amount that in their judgment should be appropriated, and how much can be safely assigned to each object to be appropriated for in the act under con- sideration. For the fiscal year ending June 30, 1909, the estimates submitted exceeded the appropriations by $285,525. Before the time of the hearing by the subcommittee on appropriations it became evident that the new National Museum building would not be completed in time to make use of the estimated $200,000 for furniture and fixtures, so at the hearing the committee was requested to approve of $50,000, which was done. The items of $40,000 for the readjustment of the boundaries of the National Zoological Park and $60,000 for altera- tions in the Smithsonian building to provide for the exhibition of the art collections of the Government were omitted by the committee along with some minor increases in the estimates. In making up the estimates for the fiscal year 1910 the Secretary had to consider, among other matters, the following: 1. The estimates submitted by the officers in charge of the several branches. 2. The reasons submitted for asking an increase in appropriations. 3. The rejection by the Congress of most of the increased estimates for the fiscal year 1909. 4. His duty as an administrative officer to submit to the Congress such estimates as in his judgment would be needed to properly pro- REPORT OF THE SECRETARY. 7 vide for carrying on the work of the federal branches of the Institu- tion. Not knowing the conditions or reasons for the rejection of certain estimates for 1909, and feeling that the committees and the Congress had approved of the general plan of operation of the several federal branches of the Institution, I have prepared estimates for the fiscal year 1910 on the basis of securing effectiveness in administration ; creditable results both in exhibition, research, and publication; and a natural development so as to compare favorably in the final result with national institutions of the same type in other countries. For instance, I have the feeling that if our Government undertakes to establish and maintain a national zoological park at the capital city it should not rank, as it does now, fifth or sixth among parks of the same type elsewhere. A carefully considered plan has been formu- lated for the development of the Zoological Park, and the estimates have been made in accordance with it. The same has been done for the National Museum and the Bureau of American Ethnology. EXPLORATIONS AND RESEARCHES. The resources of the Smithsonian Institution are at present too limited to permit of large grants for extensive explorations or inves- tigations, but as far as the income allows aid is given in various lines of research work and it is sometimes found possible to engage in ex- peditions likely to accomplish important results. If funds could be obtained to be administered under the Institution, the scientific work of the Government might often be supplemented by original re- searches of a character that would hardly be undertaken by the Government, and which would be of great service to humanity and to science. Through the National Museum, the Bureau of American Ethnology, and the Astrophysical Observatory the Institution has been enabled to carry on various biological, ethnological, and astrophysical re- searches, which will be found fully described elsewhere in this report. STUDIES IN CAMBRIAN GEOLOGY AND PALEONTOLOGY, In my last report reference was made to studies of the older sedi- mentary rocks of the North American Continent which I have been carrying on for the past twenty years. This work was continued in the Canadian Rockies during the field season of 1907. Early in July a camp outfit was secured at Field, British Columbia, and work be- gun on Mount Stephen. Subsequently sections were studied and measured at Castle Mountain, west of Banff, Alberta; at Lake Lou- ise, south of Laggan, Alberta; and on Mount Bosworth, on the Con- tinental Divide near Hector, British Columbia. Upward of 20,000 88292—sm 1908——2 8 ANNUAL REPORT SMETHSONIAN INSTITUTION, 1908. feet of strata were carefully examined and measured, and collections of fossils and rocks made from many localities. It was found that the Cambrian section included over 12,000 feet of sandstones, shales, and limestones, and that the three great divisions of the Cambrian— the Lower, Middle, and Upper—were represented in the Bow River series and the Castle Mountain group. Characteristic fossils were found in each division. At the close of the fiscal year papers were in type® describing the sections measured and giving lists of the faunas obtained at the various horizons. The field season of 1908 will be spent in Montana, British Columbia, and Alberta in an at- tempt to correlate the pre-Cambrian formations of Montana studied in 1905, with those described by Willis and Daly in the vicinity of the Forty-ninth parailel. AERIAL NAVIGATION. Within the past year there has been a renewed interest in experi- ments in aerial navigation, to which this Institution, through my pred- ecessor, Mr. Langley, made notable contributions. Toward the end of the year the demand for literature on the subject so entirely exhausted the supply of papers on hand, that a special edition of some of Mr. Langley’s more popular memoirs was issued. It is gratifying to me to be able to say that his pioneer work in heavier-than-air machines, resulting as it did in the actual demonstration of the possi- bility of mechanical flight, has now received universal recognition. Besides numerous popular papers, Mr. Langley wrote two technical works relating to the general subject of aerodromics, which form parts of an incomplete volume of the Smithsonian Contributions to Knowledge. The record of his experiments from 1893 to 1905 was kept by him partly in manuscript form and largely in the shape of voluminous notes and wastebooks. These have been turned over to his principal assistant in this work, Mr. Charles M. Manly, who has been for some time engaged in preparing them for publication and adding such necessary information, especially on the engineering side, as comes within the immediate purview of Mr. Manly’s work. It is a source of regret that the memoir has not yet been completed for publication, but I hope that during this year it will be possible for the Institution to issue the volume, thus bringing to a conclusion a record of Mr. Langley’s original and epoch-making contributions “Canadian Alpine Journal, Vol. I, No. 2, 1908, pp. 2832-248: Mount Stephen rocks and fossils. Smithsonian Miscellaneous Collections, Vol. LIII, Cambrian Geology and Paleontology, No. 5, 1908, pp. 167-280: Cambrian sections of the Cordilleran area. > Bull. Geol. Soc. America, yol. 17, 1906, pp. 1-28: Algonkian formations of northwestern Montana. REPORT OF THE SECRETARY. 9 to a science and an art which bid fair to engage the attention of man- kind for many years to come. METEOR CRATER OF CANYON DIABLO, ARIZONA. An investigation of the remarkable crater-like depression at Coon Butte, near Canyon Diablo, Arizona, made in 1907 by Dr. G. P. Merrill, head curator of geology in the National Museum, aided by a grant from the Smithsonian Institution, was briefly mentioned in my last year’s report and a full account appeared in the Smithsonian Miscellaneous Collections (quarterly issue) under date of January 27, 1908. The “crater” is some three-fourths of a mile in diameter and 500 feet in depth in a region of undisturbed sedimentary rocks and remote from volcanoes. The object of the study was to deter- mine, if possible, whether the crater was caused by volcanic action, as assumed by some investigators, or due to the impact of a mass of meteoric iron as asserted by others. From the available evidence Doctor Merrill concluded that the crater could not have been formed by volcanic action, all the observed phenomena being of a superficial nature. Some 300 feet of over- lying limestone and 500 feet of sandstone have been shattered as by some powerful blow, and the quartz particles in the sandstone in part fused, indicating a very high degree of heat. The deeper- lying sandstone, however, is entirely unchanged. These facts abso- lutely preclude the formation of the crater by any deep-seated agency, and forces the conclusion that it resulted from the impact of a stellar body. No record has been found of a meteoric fall comparable with this, the largest known meteorites, such as that from Cape York, Green- Jand, and the enormous irons from Oregon, having fallen under such conditions as to scarcely bury themselves. The nearest approach to the Canyon Diablo occurrence was that at Knyahinya, Hungary, where a 660-pound stone penetrated the ground to a depth of 11 feet. No meteoric mass of sufficient size to have made this enormous crater has been brought to ight, but it is thought there still remains the possibility of its having become dissipated through the heat developed by its impact while traveling at a speed of many miles a second. In his report Doctor Merrill goes very thoroughly into details. He has secured many specimens of the meteoric irons and their associa- tions from the locality, which are deposited in the National Museum. The specimens include a hitherto unrecognized type of meteoric iron and a peculiar form of metamorphism in the siliceous sandstone of the region. Mining operations carried on in the crater afforded special oppor- tunity for this research. These operations were discontinued during the winter, but their resumption in May, 1908, presented a second 10 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. opportunity for the observation of the unique phenomena at the erater, and Doctor Merrill was authorized to proceed again to Ari- zona to be present during this second, and probably final, series of drillings. The greatest depth reached during his stay at the crater was 842 feet, and the results of the examination of the ejectamenta thus secured confirmed the former conclusion. Several boxes of specimens bearing on the subject were forwarded to the Institution, where they will be held for future reference and study. ALASKAN EXPEDITION, In my last report mention was made of an expedition to be made to the Yukon country in Alaska for the collection of the remains of large extinct vertebrates, particularly mammals. A Smithsonian expedition had been made to this region in the summer of 1904 by Mr. Maddren, the results of which were published by the Institution in 1905. The present expedition of 1907 was in charge of Mr. C. W. Gilmore of the National Museum. The results of the explorations have been published in the Smithsonian Miscellaneous Collections. Mr. Gilmore was not successful in finding what was most desired, a fairly complete skeleton of a mammoth, but the expedition was by no means*barren of results. He found that scattered remains of Pleistocene animals occur throughout the unglaciated region of Alaska and adjacent Canadian territory in the black muck accumu- lated in gulches and the valleys of the smaller streams, in the fine elevated clays of the Yukon silts, and Kowak clays, and in the more recent fluvial and alluvial deposits. Some of the specimens are so well preserved that they could not have traveled far from the original place of interment, while many bones are broken, abraded, and waterworn. Mr. Gilmore gives a list of the various genera and species of extinct vertebrates thus far reported from Alaska, followed by a brief review with a number of illustrations. He believes that when more perfect material is available it will be found, probably in all instances, to be quite distinct from the living forms. The skull of an Ovébos was found sufficiently complete to warrant its separation from the living form O. moschatus, to which nearly all musk-ox material from this region had previously been referred. GEOLOGY OF THE ALPS. The investigation by Mr. Bailey Willis of the current theories of Alpine structure, under the grant approved in 1907, was successful in offering opportunities for consultation with leading European geologists, among whom were Rothpletz, Suess, Lugeon, Margerie, and Saccord. In cooperation with several distinguished students of the great problems of the Alps, Mr. Willis made detailed studies of REPORT OF THE SECRETARY. 11 critical districts, and was thus enabled to compare opposing theories by object lessons on the ground. Mr. Willis’s full revort is expected early in 1909. ABSOLUTE MEASUREMENT OF SOUND. Dr. A. G. Webster announces the approaching completion of his research on the measurement of sound which has been in progress for two years past. The investigation comprises an exhaustive treat- ment of the theory of the production of sound, with a descriptien of a standard source, the transmission of sound through the air as modified by the effect of the ground, and its measurement by a receiving instrument. A description of experiments confirming the theory of Doctor Webster will be included in his finished report, with several practical applications, such as the examination of the sounds of speech, the diagnosis of deafness, the improvement of fog signals, and the testing of materials for the insulation of sound. RECALCULATION OF ATOMIC WEIGHTS. In February, 1908, Prof. F. W. Clarke, chairman of the Interna- tional Commission on Atomic Weights, was authorized to begin the preparation of a third edition of his work on that subject, with the aid of a grant from the Smithsonian Institution. The second edition of Professor Clarke’s Atomic Weights was published in 1897, since which time the data on this subject have so largely increased as to render a new edition desirable. Some time will necessarily elapse before the completion of the work. PROPERTIES OF MATTER AT TEMPERATURE OF LIQUID AIR. In October, 1907, a Smithsonian grant was approved on behalf of Prof. E. L. Nichols, of Cornell University, for the continuation of his experiments on the properties of matter at the temperature of liquid air. Reports of the progress of this research are to be made from time to time in the recognized journals of physics and, at the completion of the research, a memoir describing the investigation will be submitted to the Smithsonian Institution for consideration as to publication. It is believed that the prompt announcement of results in the way mentioned will be an immediate advantage to students, and that their publication as a whole by the Institution will also prove of great service. BOTANICAL RESEARCHES IN CALIFORNIA. A moderate grant has been made to Miss Alice Eastwood from the Smithsonian fund for the critical field study and collection of the spe- cies aud genera of the plants secured at the type locality, Santa Bar- 12 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. bara, Cal., by Thomas Nuttall, and published by him in 1888 to 1843. Some of these species are now well known, but others have never been collected and arranged since they were found by Nuttall, and several are known to be misunderstood. The collection Miss Eastwood is now making will be valuable for the series in the herbarium of the National Museum. DEEP-WELL TEMPERATURES. A moderate Smithsonian grant was approved on behalf of Dr. William Hallock, of Columbia University, to assist in the investiga- tion of temperatures in a deep well near Oakland, Md., for purposes of geological research. INVESTIGATIONS UNDER THE HODGKINS FUND. T have given a good deal of consideration to the use of that por- tion of the Hodgkins fund devoted to the increase and diffusion of more exact knowledge of the atmospheric air in relation to the wel- fare of man. While much valuable work has been done under this fund, it seems to me that it would be more in consonance with the ideas of the founder, if at least a portion of it might be employed in some way to aid in the knowledge of the prevention of disease and its cure. I have been in correspondence with several specialists and hope to be able to initiate some useful investigations along these lines. HODGKINS FUND PRIZE FOR ESSAY ON TUBERCULOSIS. Under date of February 3, 1908, the Institution issued a circular announcing a prize of $1,500 for the best treatise “On the relation of atmospheric air to tuberculosis ” that should be offered at the inter- national congress on tuberculosis, to be held in Washington from September 21 to October 12, 1908. The circular reads as follows: SMITHSONIAN INSTITUTION—HODGKINS-FUND PRIZE. In October, 1891, Thomas George Hodgkins, esq., of Setauket, N. Y., made a donation to the Smithsonian Institution the ingome from a part of which was to be devoted to “ the increase and diffusion of more exact knowledge in regard to the nature and properties of atmospheric air in connection with the welfare of man.” In furtherance of the donor’s wishes, the Smithsonian Institution has from time to time offered prizes, awarded medals, made grants for inves- tigations, and issued publications. In connection with the approaching international congress on tuberculosis, which will be held in Washington, September 21 to October 12, 1908, a prize of $1,500 is offered for the best treatise “On the relation of atmospheric air to tuberculosis.” Memoirs: having relation to the cause, spread, prevention, or cure of tuberculosis are included within the general terms of the subject. Any memoir read before the international congress on tuberculosis, or sent to the Smithsonian Institution or to the secretary-general of the congress before its close, namely, October 12, 1908, will be considered in the competition. REPORT OF THE SECRETARY. 13 The memoirs may be written in English, French, German, Spanish, or Italian. They should be submitted either in manuscript or typewritten copy, or if in type, printed as manuscript. If written in German they should be in Latin script. They will be examined and the prize awarded by a committee ap- pointed by the Secretary of the Smithsonian Institution in conjunction with the officers of the international congress on tuberculosis. Such memoirs must not have been published prior to the congress. The Smithsonian Institution reserves the right to publish the treatise to which the prize is awarded. No condition as to the length of the treatises is established, it being expected that the practical results of important investigations will be set forth as convine- ingly and tersely as the subject will permit. The right is reserved to award no prize if in the judgment of the committee no contribution is offered of sufficient merit to warrant such action. Memoirs designed for consideration should be addressed to either ‘“ The Smithsonian Institution, Washington, D. C., U. S. A.” or to “Dr. John S. Fulton, secretary-general of the international congress on tuberculosis, 714 Colorado Building, Washington, D. C., U. S. A.” Further information, if de- sired by persons intending to become competitors, will be furnished on application. CHARLES D. WALCOTT, Secretary of the Smithsonian Institution. As a committee to award this prize the following gentlemen have consented to serve: Dr. William H. Welch, of Johns Hopkins, chair- man; Dr. John S. Fulton, secretary-general of the congress; Dr. Simon Flexner, director, Rockefeller Institute for Medical Research, New York; Dr. George M. Sternberg, Surgeon-General, U. S. Army, retired; Dr. Hermann Biggs, New York department of health; Dr. George Dock, of the University of Michigan; and Dr. William M. Davis, of Harvard. FLOW OF AIR AT HIGH PRESSURE THROUGH A NOZZLE. The inquiry to determine the cooling effect of the nozzle expansion of air for large pressure differences, which has been conducted by Prof. W. P. Bradley, of Wesleyan University, with the aid of a grant from the Hodgkins fund of the Institution, is announced as nearing completion. The investigation was intended specifically to determine whether the cooling process is due to the Joule-Thomson effect or to the performance of external work by the expanding air in pushing back the atmosphere from before the nozzle. The results of the in- quiry make it clear that pressure is an important factor and that the cooling effect increases very rapidly indeed as the initial temperature falls. Professor Bradley is now engaged in an exact mathematical discussion of this research. As to the apparatus employed, an interchanger of the Hampton type was so constructed, in vertical sections, that the amount of interchanger surface in actual use could be varied at will, from noth- ing to more than enough to induce liquefaction. In this manner it 14 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. was possible to maintain the initial temperature constant, within one- third of a degree, at any desired point between +20° and —120°, and the final temperature similarly constant between +-20° and the tem- perature of liquefaction. The temperatures were measured by resist- ance thermometers placed close to the valves in the high and low pressure circuits. The pressures employed range from 500 pounds to 3,000 pounds. The expansion was exclusively to one atmosphere. The inquiry is of interest as related to the functioning of air liquefiers in which the air is throttled by a valve and expands without performing external work, in the usual sense of that expression. STUDY OF THE UPPER ATMOSPHERE. A further grant from the Hodgkins fund was made to Prof. A. Lawrence Rotch, director of the Blue Hill Meteorological Observa- tory, to aid in the completion of his experiments with ballons-sondes at St. Louis. This was accomplished in October and November, 1907, under the direction of Mr. S. P. Fergusson. The object of these latest ascensions, 21 in number, was to supply data for the high atmosphere during the autumn, a season when there are few observations, and also to establish a comparison with the results obtained simultaneously in Europe on the international term days in October and November. Professor Rotch reports that all but two of the instruments used in these ascensions were recov- ered, and an examination of the record sheets indicates generally the presence, at an altitude exceeding 8 miles, of the isothermal, or rela- tively warm stratum, which was found somewhat lower in summer. For example, on October 8 the minimum temperature of 90° F. below zero was found at a height of 47,600 feet, whereas at the extreme alti- tude reached—namely, 54, 100 feet—the “queens had risen to 72° F. below zero. Similarly, on October 10 the lowest temperature of 80° F. below zero occurred at 39,700 feet, while 69° F. below zero was recorded at 49,200 feet, the limit of this ascension, showing that the temperature inversion had come down about 8,000 feet in two days. The prevailing drift of the balloons during the autumn of 1907 was from the northwest, while in previous years they traveled more from the west. A description of the methods employed in launching 77 ballons-sondes from St. Louis and a discussion of the results obtained will soon appear in the Annals of the Astronomical Observatory of Harvard College. ATR SACS OF THE PIGEON. For several years there have been in progress under the general direction of Prof. von Lendenfeld, of the University of Prague, aided by grants from the Hodgkins find various investigations bearing upon animal flight. The results of one of these investigations, on REPORT OF THE SECRETARY. 15 “ The air sacs of the pigeon,” by Bruno Miiller, was published during the past year in the Smithsonian Miscellaneous Collections. The au- thor summarizes the conclusions of his studies as follows: I do not consider the air sacs, including the air cavities of bones, as organs having a positive and special function, but rather as a system of empty inter- spaces. Their value lies in their emptiness—that is, in their containing nothing that offers resistance or has an appreciable weight. Flying is the highest form of locomotion, and as such only possible to a body of high mechanical efficiency. Our most effective machines are by no means compact and solid, but composed of parts as strong as possible in themselves and arranged in the most appropriate manner. The interspaces between the parts are left empty and taken up by air. The Sauropsida, at the time they obtained the power of flight, became adapted to its mechanical requirements, and thereby similar to the efficient machines mentioned above; they divested themselves of all superfluous material, filling the body spaces thus obtained with air sacs. While the body wall, adapting itself to the mechanical requirement, became a compact, hollow cylinder serving as a support for the organs of movement, the mobility of the parts was assured by surrounding them with air sacs. The lengthening of the neck, produced by quite a different adaptation, made necessary an increase in the quantity of air moved during respiration. This demand was met by air currents generated through a rhythmical change in the volume of the air sacs. The connection of the air sacs with the lungs is a consequence of their phylogenetic development, which is repeated in their embryological development, and has no physiological significance other than that the air sacs assist in renewing the air in the trachea. MECHANICS OF THE EARTH’S ATMOSPHERE. Prof. Cleveland Abbe, who has received a Hodgkins grant for the preparation of a second volume of translations of important foreign memoirs on the mechanics of the earth’s atmosphere, has about com- pleted this work. The former collection of translations on this sub- ject by Professor Abbe, published in 1891 as volume 34 of the Smith- sonian Miscellaneous Collections, has been widely used and recognized to be of important service to those engaged in the study of modern dynamic meteorology. NAPLES ZOOLOGICAL STATION. For the past fifteen years the Smithsonian Institution has supported a table at the Naples Zoological Station and offered its facilities for study to biologists recommended by an advisory committee of emi- nent specialists. During the past year I have been aided by the prompt and helpful action of this committee, whose membership con- tinues the same as heretofore. The occupation of the Smithsonian table was approved on behalf of Mr. J. F. Lewis, of Johns Hopkins University, for the month of March, 1908. His actual stay, however, exceeded that period by some 16 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. two weeks. Mr. Lewis has submitted an outline of his work, in which he says: My work at Naples was in continuation of lines of investigation already under way. It consisted mainly in the collection and preservation of material for a cytological study of Rhodophyce, with a view to gathering evidence as to the extent of the remarkable alternation of generations in this group of plants. Material was collected and carefully preserved of Dudresnaya coccinea, various species of Callithamnion, and other forms. My comparatively short stay at Naples precluded my making at the time the careful cytological investigation which must precede the drawing of any conclusions as to the presence or ab- sence of alternation of generations in the forms studied. This investigation is now in progress and should lead to definite results of some theoretical value. During my stay at Naples I also investigated the periodicity in the production in the sexual cells of Dictyola dichotoma. This subject has been investigated by J. Lloyd Williams on the coasts of England and Wales, and by W. D. Hoyt on our own Atlantic coast. In both cases it has been found that the production of sexual cells bears a very definite relation to the changes of the tides. It was thought, therefore, to be of special interest to find how Dictyola behaves in seas where the tides are very slight and where tidal influences are almost negligible. The results of this investigation are practically ready for publication. Prof. F. M. Andrews, of the University of Indiana, received the appointment to the table for the months of April and May, 1908, going there from a period of research work with Professor Pfeffer, at the University of Leipzig. At Naples Professor Andrews was engaged on a problem in plant physiology, a summary of the results of which will receive mention when submitted to the Institution. Dr. C. A. Kofoid, associate professor of histology and embryology in the University of California, and assistant director of the San Diego Marine Biological Station, will occupy the table for three months from January 1, 1909. While at Naples Doctor Kofoid pro- poses a research on sexual reproduction among Dinoflagellata, as yet unknown in marine forms. He will also study the Gymnodinide, which can be done only in the living condition, as they resist all attempts at fixing. In addition to these investigations, he proposes some experimental work on autotomy in Ceratium, with reference to temperature and vertical distribution in the sea. The application of Dr. M. F. Guyer, professor of zoology in the University of Cincinnati, has been approved for April, May, and June, 1909. Doctor Guyer has contributed to various scientific publi- cations articles already well known, describing his investigations, and on the close of his term at Naples is expected to send a brief outline of his work there to the Institution. To avoid the complications which may arise from the overlapping of the dates of appointees to the table, a longer time is at present allowed between the approval of an appointment and the time of occupation than was at first found practicable. It is hoped that this plan will allow a wider choice in the selection of dates, and tend to REPORT OF THE SECRETARY. 17 make the table available for the use of a greater number of investi- gators than could otherwise be accommodated. In the past fifteen years only one instance has occurred in which an investigator has applied for the Smithsonian seat after having asked the privilege of occupying another table for the same period. The confusion which necessarily results from such action will be readily appreciated. To meet the wish of the director, a double ap- pointment on behalf of the Institution, for even a limited time, is not approved without inquiry as to the convenience of the station in the matter. It should be again noted, however, that the director of the station is always most courteously ready to arrange for the accommo- dation of more than one appointee when, on being notified in advance, he finds such action practicable. PUBLICATIONS. Three series of publications are maintained by the Institution proper, (1) the Smithsonian Contributions to Knowledge, (2) the Smithsonian Miscellaneous Collections, and (3) the Annual Reports to Congress; while under its auspices there are issued Annual Re- ports, Proceedings, and Bulletins of the National Museum, Annual Reports and Bulletins of the Bureau of American Ethnology, and Annals of the Astrophysical Observatory. The Smithsonian Contributions to Knowledge are restricted to positive additions to human knowledge resting on original research, unverified speculations being excluded therefrom. The Smithsonian Miscellaneous Collections contain reports showing progress in partic- ular branches of science, lists and synopses of species of the organic and inorganic world, accounts of explorations, and aids to biblio- graphical investigations. Three memoirs of the Smithsonian Contributions to Knowledge, which were in press at the close of the last fiscal year, have been com- pleted and distributed. One of these is a memoir of 147 pages and 42 plates by Dr. William Hittell Sherzer, giving the results of his stud- ies of the glaciers of the Canadian Rockies and Selkirks. Doctor Sherzer explains the physiographic changes of the past and those now in progress in these regions, and gives the results of his observa- tions on the structure of glacial ice and movements of the glaciers. The second completed memoir of 79 pages and 10 plates is by Prof. K. A. Andrews, on “ The Young of the Crayfish Astacus and Cam, barus,” and the third memoir of 231 pages and 13 plates is by Prof. Hubert Lyman Clark, on “ The Apodous Holothurians, a Monograph of the Synaptide and Molopodiide,” including a report on the repre- sentatives of these families in the National Museum collections. 18 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. To meet the continued demand for the memoir by the late Secretary Langley on “The Internal Work of the Wind,” first issued in 1893, a new edition has been put to press, adding to the original a translation of a “ Solution of a Special Case of the General Prob- lem,” by Réné de Saussure, which appeared in the French edition of the work in 1893. Forty papers were published in the Smithsonian Miscellaneous Col- lections during the year, 32 of them aggregating 500 pages, in the quarterly issue of that series, and 8 papers, 647 pages, in the regular series. These papers cover a wide range of topics, as enumerated by the editor in his report on publications. There was published in the Smithsonian Miscellaneous Collections a paper on “ The Development of the American Alligator ” describ- ing the results of investigations by Prof. Albert M. Reese, of Syra- cuse University, who had been aided in his work by a grant from the Smithsonian Institution. A brief paper recording the observa- tions by Professor Reese on the breeding habits of the Florida all- gator was published in the Quarterly Issue of the Miscellaneous Col- lections under date of May 4, 1907. A volume of the Smithsonian Miscellaneous Collections will be devoted to a series of papers by the secretary on Cambrian geology and paleontology. Two papers of this series, No. 1, “ Nomenclature of Some Cordilleran Formations,” and No. 2, “ Cambrian Trilobites,” were published before the close of the fiscal year. Three additional papers were in proof form at the close of the year, namely, No. 3, “Cambrian Brachiopoda: Descriptions of New Genera and Species; ” No. 4, “ Classification and Terminology of the Cambrian Brachio- poda;” and No. 5, “ Cambrian Sections of the Cordilleran Area.” The series of Smithsonian Tables continues to be in demand. So Ake £4 ee Sel. es le ee ee ee 72, 600. 00 The allotments to the Institution and its branches under the head of public printing and binding during the past fiscal year were as far as practicable expended prior to June 30. The protracted session of Congress, however, prevented the completion of considerable work in hand during the latter part of the fiscal year, making it impossible to entirely use some of the allotments. Continuing the policy established last year, an editorial assistant has been engaged in abstracting such publications of the Institution and its branches as could be put in popular language for the use of newspapers throughout the country. A number of more general arti- cles on the work of the Institution have also been distributed to the REPORT OF THE SECRETARY. il press. This has resulted in reaching millions of readers who would not have ready access to the scientific information in the publications of the Institution. ADVISORY COMMITTEE ON PRINTING AND PUBLICATION, In order that the practice of the Institution in the supervision of its publication and those of its branches might correspond with that of the executive departments, as prescribed by the President’s order of January 24, 1906, the Smithsonian advisory committee on printing and publication, appointed February 7, 1906, held 26 meetings during the year and reported on 137 manuscripts and numerous blank forms. The committee also considered various questions pertaining to print- ing and binding. The committee consists of the following members: Dr. Cyrus Adler, assistant secretary, chairman; Dr. F. W. True, head curator of biology, U. S. National Museum; Mr. F. W. Hodge, ethnologist, the Bureau of American Ethnology; Dr. Frank Baker, superintendent, National Zoological Park; Mr. C. G. Abbot, director of the Astro- physical Observatory; Mr. W. I. Adams, of the International Ex- changes; Mr. A. Howard Clark, editor of the Smithsonian Institu- tion, and Dr. Leonhard Stejneger, curator of reptiles and batrachians, U.S. National Museum. The printing committee formulated a series of rules for the abbre- viation of scientific periodicals in publications of the Smithsonian and its branches. These rules, which have been approved for the use of the Institution and its branches, are given in full in the editor’s report. They may be summarized as follows: 1. In-abbreviating words in titles, stop before the second vowel, unless the resulting abbreviation would contain but one consonant, in which case stop before the third vowel. 2. All articles, prepositions, and conjunctions are to be omitted, except and and for, which may be retained when necessary for clearness. 3. In abbreviated titles, the words should follow strictly the order of the full titles. 4. (a) Words of one syllable, (b) titles consisting of a single word, (c) names of towns (except as indicated under rule 5), (d@) names of persons (when unmodified), and (e) names of geological formations are not to be abbreviated. 5. Whenever necessary for clearness any of the foregoing rules may be dis- regarded, but in such cases words should not be abbreviated. LIBRARY. The accessions to the Smithsonian library during the year aggre- gated 36,068 in volumes and parts, an increase by some 1,800 entries over the previous year. Of these accessions 24,777 were placed in the Smithsonian deposit in the Library of Congress, which comprises in 22 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. itself the largest library of scientific works in this country; 3,317 were divided among the libraries of the Secretary’s office, the Astro- physical Observatory, the National Zoological Park, and the Inter- national Exchanges, as expedient for purposes of administration, and 7,974 were deposited in the United States National Museum hbrary. Besides these, there were numerous additions to the brary of the Bureau of American Ethnology, which is administered separately. It is estimated that an equivalent of 6,560 volumes was transmitted to the Library of Congress, comprising in actual numbers 25,524 pub- lications in the form of parts of periodicals, pamphlets, and volumes. These two counts do not include public documents presented to the Smithsonian Institution, sent direct to the Library of Congress as soon as received, without stamping or recording; or public documents and other gifts to the Library of Congress received through the inter- national exchange service, or publications requested to complete sets in the Smithsonian deposit at the Library of Congress, which have been transmitted separately. As the result of a special effort to secure missing parts to complete sets, 500 new periodicals were added to the lists and about 1,559 parts lacking in the sets were received, which partially or entirely filled up the various series of publications in the Smithsonian deposit. In writing for the missing parts of publications needed to complete these sets the library has had assistance from the international ex- change service of the Institution. In addition the Institution has, through the medium of the international exchatige service, sent out requests for government documents and serial publications needed to complete the sets in the Library of Congress, and with this end in view letters have been written to Bavaria, the province of Buenos Aires, Costa Rica, Greece, Guatemala, Honduras, Newfoundland, Nicaragua, Japan, Russia, and Salvador. Over 3,300 publications were issued during the year for consultation by members of the staff and by various bureaus of the Government. In addition to the regular work in the lbrary, the assistant libra- rian has reconstructed the memorandum list of the engravings and art collection of Mr. George Perkins Marsh, purchased in 1849, what- ever catalogue may have been made having been destroyed in the fire of 1866, and has been engaged in preparing a bibliography of aero- nautical literature. PRESERVATION OF ARCHEOLOGICAL SITES. I have heretofore called attention to what had been done toward the preservation of archeological objects on the public domain from destruction by vandals and relic hunters and toward making these antiquities accessible under proper rules and regulations. Under the terms of an act of Congress approved June 8, 1906, uniform regu- REPORT OF THE SECRETARY. 25 lations for its administration were prepared by the Secretaries of the Interior, War, and Agriculture, with the cooperation of the Smith- sonian Institution, and were promulgated on December 28, 1906, in the form printed in my last report to the Regents. Under rule 8, applications for permits are referred to the Smithsonian Institution for recommendation. During the past year I have acted upon several such applications. The conservation of the nation’s archeological possessions was regulated by law none too soon to prevent further mutilation or useless destruction of interesting antiquities in many places. The President of the United States, by executive proclamation during the year, made several additions to the list of national monu- ments, including three of archeological interest: (1) the Tonto Na- tional Monument in Arizona, where there are two cliff dwellings not yet reported on; (2) the Gila Cliff-Dwellings National Monument in the Gila National Forest in New Mexico, comprising a group of cliff dwellings, and (3) the Grand Canyon National Monument, which includes a large number of cliff dwellings, pueblos, dwelling sites, and burial places in the Grand Canyon of the Colorado. CASA GRANDE RUIN IN ARIZONA. In 1906 Congress granted an appropriation of $3,000 to be ex- pended under the supervision of the Secretary of the Smithsonian Institution for the preservation of the Casa Grande ruin in Pinal County, near Florence, Ariz., and for the excavation of the reserva- tion. An account of the work accomplished by Doctor Fewkes up to June 30, 1907, was published in the Smithsonian Miscellaneous Collections under date of October 25, 1907. The work done during the past fiscal year, under a second appropriation, is noted in Appen- dix II of the present report. The largest structure excavated at Casa Grande is a building 200 feet long with 11 rooms, the massive walls inclosing a plaza. In the central room there is a seat called by the Pima Indians “the seat of Montezuma.” The ruins at Casa Grande are found to be very much more extensive than was antici- pated, and their permanent preservation is of great archeological importance. MESA VERDE NATIONAL PARK. In addition to the work of excavation, preservation, and repair of the cliff dwellings and other prehistoric ruins in the Mesa Verde National Park in Colorado, which was intrusted by the Interior Department to the direction of the Institution in February, 1908, a moderate grant from the Smithsonian fund was approved this year for additional general studies of the prehistoric culture of the Gila §8292—sm 1908——3 24 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Valley, outside the Casa Grande Reservation. Dr. J. Walter Fewkes, who directed the Mesa Verde explorations, has prosecuted this later research also and will submit an account in detail of what he has done, for publication by the Institution. The work thus far accom- plished by Doctor Fewkes is briefly described in Appendix II of the present report. CORRESPONDENCE. The correspondence of the Institution, besides serving its purposes in administration, furthers to a degree the second fundamental object of the Institution, the diffusion of knowledge among men. Through this department are received inquiries on the most varied topics relating to almost every field of science, all of which, so far as prac- ticable, are answered by a member of the staff familiar with the sub- ject concerning which information is desired. The Institution however, does not attempt to maintain a universal information bureau, nor does it seek to answer queries of a commercial nature for in- formation which may be secured from a professional advisor upon payment of a fee. | In addition to this general correspondence, there is carried on by the several branches of the Institution a considerable correspondence relating to the respective activities of each. All matters affecting questions of policy, and all appointments, however, receive the personal consideration of the secretary. During the past year newer and more convenient cases have been installed for filing letters, and certain improvements in methods of | indexing and arranging letters have been made. CONGRESSES AND CELEBRATIONS. International Zoological Congress—The Seventh International Zoological Congress met in Boston, August 19 to 25, 1907. Dr. Richard Rathbun, assistant secretary, Dr. Theodore Gill, and Dr. William H. Dall were delegates on the part of the Smithsonian In- stitution; Dr. F. W. True, Dr. Leonhard Stejneger, and Dr. Harrison G. Dyar on the part of the United States National Museum, and Dr. Frank Baker on the part of the National Zoological Park. These gentlemen were also designated by the Department of State as rep- resentatives of the United States Government. In addition, Doctor Gill served as delegate on the part of the Washington Academy of Sciences and the Biological Society of Washington, and to represent His Siamese Majesty. After the Boston meeting the congress paid a visit to Washington from September 3-6, during which time the members were entertained by a trip and luncheon in the National Zoological Park and by an informal reception at the National Mu- seum and the Smithsonian Institution. REPORT OF THE SECRETARY. 25 International Congress on Tuberculosis—In connection with the Sixth International Congress on Tuberculosis to be held in the new United States National Museum building in Washington, September 21 to October 12, 1908, the Institution has offered from the Hodgkins fund a prize of $1,500 for the best paper “ On the relation of atmos- pheric air to tuberculosis,” mention of which is made elsewhere in this report. The Secretary of the Institution is a member of the head committee on International Congress on Tuberculosis. Centenary, London Geological Society——The centenary celebration of the Geological Society of London was held September 26, 27, and 28, 1907, at which the Smithsonian Institution and the United States National Museum were represented by Dr. Arnold Hague. Doctor Hague reported the gathering of a distinguished body of eminent geologists from all parts of the world. Mathematical Congress—The Fourth International Congress of Mathematicians met at Rome, April 6-11, 1908. The Institution was represented by Prof. Simon Newcomb. Congress of Orientalists—At the fifteenth session of the Interna- tional Congress of Orientalists, to be held in Copenhagen, Denmark, August 14-20, 1908, Dr. Paul Haupt, of the United States National Museum and Johns Hopkins University, has been designated to rep- resent the Institution. Upon recommendation of the Institution the following gentlemen have been designated by the Department of State as delegates on the part of the United States Government: Dr. Paul Haupt; Dr. C. R. Lanman, of Harvard University; Prof. Morris Jastrow, jr., of the University of Pennsylvania; and Prof. A. V. W. Jackson, of Columbia University. Congress of Americanists.—The Sixteenth International Congress of Americanists will be held in Vienna, Austria, September 8-14, 1908. Dr. Franz Boas, of Columbia University, has been named to represent the Institution; and the Department of State, at the sug- gestion of the Institution, has designated, besides Doctor Boas, the following-named gentlemen delegates on the part of the United States Government: Prof. Marshall H. Saville, of Columbia; Dr. George Grant McCurdy, of Yale; Dr. Charles Peabody, of Harvard; and Dr. Paul Haupt, of Johns Hopkins. Fishery Congress.——In connection with the International Fishery Congress, to meet in Washington September 22-26, 1908, the Insti- tution made an allotment of $200 from the Smithsonian fund for the best essay or treatise on “ International regulation of the fisheries on the high seas; their history, objects, and results.” Other congresses and meetings.—At the meeting of the National Academy of Sciences in New York, November 19-21, 1907, your Secretary presented a brief résumé of some of his special geological 26 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. researches in a paper entitled “Summary of studies of Cambrian brachiopods.” At the First Pan-American Scientific Congress, to meet in Santiago, Chile, December 25, 1908, to January 5, 1909, Mr. W. H. Holmes, chief of the Bureau of American Ethnology, has been designated by the Department of State, upon the recom- mendation of the Institution, to represent the United States Govern- ment in the section of anthropology and ethnology. Prof. Morris Jastrow, jr., of the University of Pennsylvania, and Dr. Paul Haupt, of the Johns Hopkins University, have been suggested by the Institu- tion as delegates on the part of the United States to the Third Inter- national Congress for the History of Religions, to meet at Oxford, September 15-18, 1908. The Institution has subscribed to member- ship in the First International Congress on Refrigerating Industries to be held in Paris, October 5-10, 1908. MISCELLANEOUS. Hamilton fund lecture.—In 1871 a bequest was made to the Smith- sonian Institution by Mr. James Hamilton, as follows: I give one thousand dollars to the Board of Regents of the Smithsonian Institution, located at Washington, D. C., to be invested in some safe fund, and the interest to be appropriated biennially by the secretaries, either in money or a medal, for such contribution, paper, or lecture on any scientific or useful subject as said secretaries may approve. The bequest was accepted, but the income was allowed to accrue until it amounted to the principal, the interest of which now gives biennally $240. The first use made of this fund was in 1905, when Dr. Andrew D. White was invited to deliver a lecture on “ The diplomatic service of the United States, with some hints toward its reform.” Doctor White delivered this lecture in one of the halls of the National Museum in Washington, and it was subsequently printed by the Institution in the Smithsonian Miscellaneous Collections and widely distributed. The second lecture under the auspices of this fund was delivered on Wednesday evening, April 22, 1908, at Hub- bard Memorial Hall, Washington, by Dr. George E. Hale, on “ Some recent contributions to our knowledge of the sun.” Seismology.—The Institution has received during the year a num- ber of letters and reports on earthquakes in various parts of the world, and has communicated the information therein to Prof. Harry Field- ing Reid, of Johns Hopkins University, the representative of the United States on the International Seismological Association. In the Congressional diplomatic ¢ appropriation for 1909 there was included the item, “ For defraying the necessary expenses in fulfilling the obli- gations a the United States as a member of the Taiciarunia sav Seis- mological Association, including the annual contribution to the ex- penses of the association, and the expenses of the United States dele- REPORT OF THE SECRETARY. oT gate in attending the meetings of the commission, one thousand three hundred dollars.” The publications of the Seismological Association are distributed to American correspondents through the medium of the International Exchanges. Hayden Memorial Medal——tThere was presented to the Secretary of the Smithsonian Institution on January 7, 1908, the Hayden memo- rial geological medal. This gold medal was established by the Phila- delphia Academy of Natural Sciences as a memorial of Prof. F. V. Hayden, the eminent geologist and explorer, and was presented to Doctor Walcott in these terms: “ In recognition of the value of your individual contributions to geological science and of the benefits de- rived from your able and conscientious discharge of the official trust confided to you.” NATIONAL MUSEUM. The operations of the National Museum showing the progress made during the year and the present condition of the collections are dis- cussed in the appendix to the present report and in a separate volume by the assistant secretary in charge, and need not here be taken up in detail. Over 200,000 anthropological, biological, and geological speci- mens were received during the year, including many objects of extreme interest. The most important loan addition to the his- torical collections was the American flag, nearly 30 feet square, which floated over Fort McHenry during the war of 1812 and which was the inspiration for the writing of the verses of the “ Star- Spangled Banner,” by Francis Scott Key. Relating to ethnology and biology, there were received, as in former years, many important contributions from Dr. W. L. Abbott and Maj. Edgar A. Mearns. Many zoological and botanical specimens have been deposited by the Department of Agriculture, the Bureau of Fisheries, and other gov- ernment institutions. In geology the most important accessions included the Hambach collection of fossil invertebrates, purchased by the Smithsonian Institution, some rare species of fossil reptiles and mammals from South America, and fossil mammals from Alaska. I may also mention a large series of Cambrian fossils collected by me in British Columbia and Idaho. Specimens of rocks and ores, mainly from the Geological Survey, were added to the collections; also a number of rare minerals. While the museum is the custodian of government collections, and while to the public its main feature is the exhibition of character- istic objects in its several divisions, yet the law demands that the material shall be classified and properly arranged, a task which involves a large amount of research work. The work during the 28 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. past year covered many fields, including prehistoric archeology in Arizona and elsewhere, studies on the human skeleton of different races, physiological and medical observations among the Indians of the Southwest, fossil whales, reptiles of Japan, the Philippines, and North America, corals of the Hawaiian Islands, the study of meteor- ites from Canyon Diablo, Arizona, and other localities, besides ex- tensive investigations on fossil invertebrates, mammals, reptiles, and plants. The museum has continued in the customary way to advance the interests of teaching by distributing carefully labeled and classified sets of specimens to educational establishments throughout the coun- try. Twelve thousand specimens were thus distributed during the year. In conjunction with the Institution the museum participated in the expositions at Jamestown and Bordeaux and much of the material prepared for these occasions has since been incorporated in the museum collections. On the new building for the National Museum fair progress was made during the year and at its close the walls had been entirely com- pleted and the construction of the roof was well under way. The fitting up of the interior, however, involves a very large amount of work, since it includes the covering with suitable materials of some 10 acres of floor space. An interesting loan collection of over 650 specimens of laces, em- broideries, old and rare pieces of porcelain, enamels, jewelry, and other artistic objects has been temporarily installed in the hall occu- pied by the gallery of art. These objects were gathered and arranged by an informal committee of ladies, with Mrs. James W. Pinchot as chairman. It is hoped that this exhibit may be the nucleus of a per- manent collection of objects of this class. NATIONAL GALLERY OF ART. The paintings forming the nucleus of the National Gallery of Art have been exhibited during the past year not under the most favor- able circumstances, owing to the Congress not having provided an appropriation for furnishing suitable quarters. Nevertheless, some important donations of pictures were received. Mr. William T. Evans made a number of additions to his collection of contemporary American artists, a deposit of thirteen historical marine paintings by the late Edward Moran was made, and several gifts of single paint- ings were accepted. By act of Congress approved May 22, 1908, the colossal marble statue of Washington by Horatio Greenough, which since 1875 has occupied its well-known position in front of the Capi- tol, was transferred to the custody of the Smithsonian Institution. REPORT OF THE SECRETARY. 29 In order to maintain a proper standard of merit in the acceptance of works of art an advisory committee of five artists has been desig- nated. Three members of this committee were by request selected by three leading art associations of the country and two members were named by the Institution. The committee met at the Smith- sonian Institution on April 16, 1908, and organized by the election of Mr. Francis D. Millet as president and Mr. W. H. Holmes, of the Smithsonian Institution, as secretary. The other members of the committee are Mr. Frederick Crowninshield, of the Fine Arts Feder- ation of New York; Mr. Edwin H. Blashfield, of the National Acad- emy of Design; and Mr. Herbert Adams, of the National Sculpture Society. BUREAU OF AMERICAN ETHNOLOGY. The Bureau of American Ethnology has continued its investiga- tions among the Indian tribes of the country begun over a quarter of a century ago. While seeking to cover in the most comprehensive manner the whole range of American ethnology, the bureau has taken particular care to avoid entering upon researches that are likely to be provided for by other agencies, public or private. The results sought by the bureau are: (1) Acquirement of a thorough knowledge of the American Indian tribes, their origin, relationship to one an- other and to the whites, location, numbers, capacity for civilization, claims to territory, and their interests generally, for the practical purposes of government; and (2) the completion of a systematic and well-rounded record of the tribes for historic and scientific purposes before their aboriginal characteristics and culture are too greatly modified or are completely lost. Since it has not been possible to study all of the tribes in detail, a sufficient number have been taken as types to stand for all. The work accomplished in securing knowledge of these tribes has been recorded in the annual reports of the bureau, and the results ob- tained have been published, so far as circumstances will permit, in bulletins of the bureau. Many manuscripts are preserved in the archives of the bureau. To the present time there have been col- lected data relating to some 60 families of linguistic stocks and upward of 300 tribes. During the past year this fund of knowledge was added to through researches carried on in Arizona, New Mexico, Colorado, Texas, Minnesota, Pennsylvania, and Ontario. Investi- gations in the field, however, were not as extensive as in some previous years, on account of the necessity of retaining nearly all of the ethnologic force in the office for the purpose of completing the Handbook of American Indians, part 1 of which was published last 30 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. year. The handbook is in the nature of a summary of knowledge gained thus far concerning the American Indians. The demand for the part of the work published has been so great that the bureau has found it impossible to supply even a third of the copies requested by correspondents. The quota under control of the Superintendent of Documents also was soon exhausted, necessitating the reprinting of an edition of 500 copies (the limit allowed by law) to fill the orders received. As the main body of part 2 was in type at the close of the fiscal year, it is expected that this part will be issued in the course of a few months. In editing the handbook during the year the staff of the bureau was generously aided by upward of thirty specialists throughout the country, who rendered all possible assist- ance in their particular fields. A work of somewhat similar purpose is a Handbook of American Indian Languages, the manuscript of which was practically completed at the close of the fiscal year. For the first time the study of native Indian music was seriously taken up by the bureau in connection with certain investigations re- lating to the grand medicine ceremony of the Chippewa on the White Earth Reservation, Minn. The phonograph was employed in recording the songs. Records of songs were also secured from mem- bers of various Indian delegations visiting the capital. This study and recording of the Indian tribes is not only of national importance but urgent. The native American race, one of the four ‘aces of men, is fast disappearing, and the processes of obliteration are sure. If authoritative investigations are not made now, they never can be made with any like degree of accuracy or of thoroughness. It is a work the nation owes to science, to the Indian race, and to itself. It is a work worthy of a great nation, and one which can be carried on systematically only by a nation. Through the researches of the bureau the world is not only securing, while possible, a permanent record of one of the great races of men now dying, but is gaining a knowledge of the Indian for practical purposes of administration and in the interest of humanity. INTERNATIONAL EXCHANGES. The promotion of literary and scientific intercourse between this country and other parts of the world has been vigorously earried for- ward during the past year through the system of international ex- changes. The details of the regular work of the service are given in full in the report on the exchange service and only the more important matters are referred to here. The growth of this service has been made possible through the action of Congress and of our Government in negotiating treaties with other nations to place the exchange of government, scientific, and literary publications upon a definite, legal, international footing. REPORT OF THE SECRETARY. 31 Through an increase in the appropriation granted by Congress it was possible during the year to inaugurate a system of work which had long been in mind—that of actively seeking returns from foreign countries for the exchanges sent to them by this Government and its departments and bureaus. The result has already been more than satisfactory, but the effort is so recent that its full fruition can hardly be expected within the year. A number of most gratifying acknowl- edgments have been received from various departments of the Goy- ernment regarding this new work. The transmission of packages has been much more prompt during the past twelve months than during any like period in the history of the service, shipments being made to all countries at least once a month. At the request of the Russian Commission of International Ex- changes, en behalf of the library commission of the Douma, the interchange of parliamentary publications has been entered into with Russia. The French Chamber of Deputies has also made a request, through the Department of State, for the exchange of parliamentary docu- ments, and the matter was communicated to Congress by the depart- ment during the last session. At the time the convention for the exchange of official documents and scientific and literary publications was concluded at Brussels in 1886, an agreement was also entered into between the United States and several other countries for the immediate exchange of official journals, etc., but in the absence of the necessary legislation by Congress no steps have been taken by the Institution to carry this agreement into effect. As the subject has now been brought to the attention of Congress, it is hoped that a sufficient number of copies of the Congressional Record may be set aside for this purpose. In accordance with treaty stipulations and under the authority of the congressional resolutions of March 2, 1867, and March 2, 1901, setting apart a certain number of documents for exchange with for- eign countries, there are now sent regularly to depositories abroad 54 full sets of United States official publications and 32 partial sets, China having been added during the year to the list of countries receiving full sets and Montenegro and Liberia to the list of those receiving partial sets. As a result of correspondence between the Smithsonian Institution and the diplomatic envoys from the Republic of Liberia, regarding the establishment of a bureau of international exchanges in that country and the interchange of official documents between that country and the United States, the department of state at Monrovia has been designated to act as the exchange intermediary between 32 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the two countries, and the proposition to exchange official publica- tions has been accepted by the envoys. The total number of packages handled by the International Ex- change Service during the past year was 203,098, an increase over the number for the preceding year of 18,268. The weight of these packages was 435,285 pounds, 70 per cent of which was in the interest of the United States Government. The Smithsonian Institution, through its system of exchanges, is in correspondence with 60,123 establishments and individuals, 48,340 of which are exterior to the borders of the United States. These correspondents are scattered throughout the world, and there are few places, however remote, which do not profit by the service. NATIONAL ZOOLOGICAL PARK. By authority of the act of Congress approved April 30, 1890, estab- lishing the National Zoological Park, “ for the advancement of sci- ence and the instruction and recreation of the people,” collections of living animals, now numbering 1,402 individuals, have been brought together from all parts of the world, and housed as nearly as pos- sible in surroundings natural to them. These collections at the close of the fiscal year included 350 species: Mammals, 146; birds, 168; and reptiles, 36. By exhibiting the animals, properly labeled, the object of instruct- ing and entertaining the visitors, of which there were 652,500 (in- cluding 4,688 school children) during the year, was furthered, and by study of the specimens the advancement of science was in a measure attained. In September the park was visited by the Inter- national Zoological Congress, about eighty members of which spent a day examining the collections. As in previous years specialists of the Department of Agriculture studying animal diseases were offered opportunities for pathological investigations when animals died, and such dead animals as might be useful to the national col- lections were sent to the National Museum. This to a certain degree was in keeping with the first purpose in establishing the park, namely, “the advancement of science.” It has not as yet been pos- sible, however, owing to the yearly present necessities, to fully carry out plans in this regard formulated at the time of the organization of the park. Designs have been drawn for a much-needed laboratory and hospital building, through the erection and equipment of which it is hoped not only that the welfare of the Government’s animals may be even more thoroughly guarded, but investigations of a zoological nature for the increase of practical and scientific knowledge may be prosecuted. With one exception no particular appropriation has been made for REPORT OF THE SECRETARY. 33 the erection of buildings for the animals in the park since its estab- lishment. The wooden structures which originally sheltered the animals could therefore be replaced only as strict economy in admin- istration expenses permitted. As the appropriations for adminis- tration for a number of years have been but little more than sufficient to maintain the park, it can not now be said how soon the plans for the new building may be carried into effect. There is also needed a new aquarium building, since the present structure, originally built in the most temporary manner for use as a hay shed, is fast falling into decay, and a general aviary, antelope house, inclosures for sea lions and seals, and a centrally located office building are much desired. Under the special appropriation allowed for the reconstruction and repairing of walks and roadways the most notable improvements of the year have been made, several long concrete approaches having been constructed, and a considerable portion of roadbed having been remade. As in previous years, particular attention has been devoted to preserving the natural beauty of the grounds. During the year there were 591 accessions, which included 6% gifts, 91 births, 397 purchases, and 32 exchanges. There were 382 losses, by death, exchange, and return of animals. Total number June 30, 1908, 1,402. ASTROPHYSICAL OBSERVATORY. The work of the Astrophysical Observatory during the last fiscal year has consisted (1) of solar observations on Mount Wilson, Cali- fornia, and at Washington, (2) a solar eclipse expedition to Flint Island in the southern Pacific, and (3) the final preparation and pub- lication of the second volume of the Annals of the Observatory. The Mount Wilson observations, continued from the summers of 1905 and 1906, were directed toward securing as many records of intensity of solar radiation as possible for the study of solar changes. As in former years, other kinds of measurements were made, notably on the brightness of the sky and on the reflection of the clouds. Since the observations as a whole have shown that the variation of solar radiation is highly probable, and since numerous days suitable for solar radiation measurements were found in the months from May to November on Mount Wilson, it is proposed to erect, on a small and well-isolated plot of ground leased for the purpose, a fire- proof observing shelter to be occupied by Smithsonian observers each year during the months mentioned. This will enable frequent obser- vation of the “ solar constant ” during a period of years at least equal to the sun-spot cycle, a research regarded as of great importance by the late director, Mr. Langley. The work at Washington included the observation, with improved methods, of the relative brightness of 34 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. different parts of the sun’s disk, and preliminary measurements, re. quiring exceptional care, of the absorption of water vapor in long columns of air, for the region of the spectrum where rays are chiefly emitted by the earth. The Smithsonian expedition to Flint Island in the southern Pa- cific to study the solar eclipse of January 3, 1908, was made in co- operation with Director Campbell, of the Lick Observatory, the party being absent from Washington from November 5, 1907, to February 12, 1908. It was proposed to measure, with that extremely sensitive electrical thermometer called the bolometer, the intensity of the radiation of the solar corona, and to determine the quality of coronal light as compared with sunlight. This is an observation that it is very unlikely will ever be possible except during an eclipse. In general terms the bolometric results indicate that the coronal radia- tion differs but little in quality from that of the sun, and is in fact far richer than the reflected rays of the moon in visible light, although less rich than skylight. Observations as to the nature of the corona were such as to lead at least to the suggestion that gases are present along with solid and liquid particles. The exact con- clusions reached are given fully in the report of the director. The second volume of the Annals, issued in April, includes an account of the work of the Observatory from 1900 to 1907. Com- mendatory notices by letter and in the journals and requests for copies of the work have been numerous. Speaking broadly, the energy of the Observatory was devoted, during the period covered by the volume, to an investigation of the intensity of the rays of the sun and the dependence of the earth’s temperature upon the radia- tion. The investigations have resulted in apparently definitely fixing the approximate average value of the “ solar constant ” at 2.1 calories per square centimeter per minute, and in showing decisively that there is a marked fluctuation about this mean value sufficient in magnitude to influence very perceptibly the climate, at least of the inland regions, upon the earth. INTERNATIONAL CATALOGUE OF SCIENTIFIC LITERA- TURE. The organization known as the International Catalogue of Sci- entific Literature has by means of the cooperation of all of the principal countries of the world been publishing since 1901, in seven- teen annual volumes, a classified author’s and subject index catalogue of the current scientific literature of all the civilized countries of the world. Each country collects, indexes, and classifies the scientific literature published within its borders and furnishes to the central bureau in London the material thus prepared for publication in the REPORT OF THE SECRETARY. 35 annual volumes. The cost of preparation is borne by the countries taking part in the enterprise, in the great majority of cases the sup- port being derived through direct governmental grants. The entire cost of printing and publishing is borne by the subscribers to the catalogue, which include, besides individuals, the leading American universities, libraries, and scientific societies. That all sections of the civilized world are now represented in this enterprise is shown by the following lst of regional bureaus now established and regularly furnishing the London central bureau classified citations of scientific papers published within their domains: Austria, Belgium, Canada, Cuba, Denmark, Egypt, Finland, France, Germany, Greece, Holland, Hungary, India and Ceylon, Italy, Japan, Mexico, New South Wales, New Zealand, Norway, Poland (Austrian, Russian, and Prussian), Portugal, Queensland, Russia, South Africa, South Australia, Spain, Sweden, Switzerland, United States of America, Victoria, and Western Australia. During the year there was combined with the International Cata- logue of Scientific Literature the annual publication known as the Zoological Record, which has been prepared for many years by the Zoological Society of London. This, it is hoped, is merely prelimi- nary to the association of a number of independent scientific bibli- ographies and yearbooks with the International Catalogue of Scien- tific Literature. Under the congressional allotment of $5,000 for the last fiscal year, aS in previous years, 28,528 references to American scientific literature were completed and forwarded to the central bureau in London for publication. Respectfully submitted. Cuartes D. Watcort, Secretary. APPENDIX I. REPORT ON THE UNITED STATES NATIONAL MUSEUM. Sir: I have the honor to submit the following report on the operations of the United States National Museum for the fiscal year ending June 30, 1908: The ever-increasing crowded condition of the two buildings occupied by the National Museum has made it more difficult each year to provide for the collec- tions and to insure their safety and orderly arrangement. It is, therefore, but natural that the completion of the large new building, with its greater con- veniences, should be eagerly awaited, and it is hoped that the work of moving in can begin before the close of another year. At the commencement of the fiscal year the outer walls of this structure had been carried to the height of the lintels at the top of the second story on the eastern section of the building, but not so high on the western. Work on the two entrance pavilions had only reached the top of the basement story, but the steel work and arches of the second floor were in place, and the lecture hall in the basement had been inclosed and partly vaulted. Fair progress was made during the year, and at its close the walls had been entirely completed except at the south pavilion, which is to contain the main entrance and the rotunda, and the construction of the roof was well under way. The fitting up of the interior, however, involves a very great amount of work, since it includes the covering with suitable materials of some 10 acres of floor space, the building of many partitions, the plastering of walls, piers, and ceilings, and the introduction of boilers, machinery, and minor appliances for heating, venti- lation, lighting, and various other purposes, besides the furnishings for the halls and rooms. The buildings occupied for many years have been kept in excellent condition, and the museum building has been much improved by replacing its original and imperfect roofs, which have always been a source of great annoyance. The rebuilding of these roofs with tin, begun three years ago, was, with the exception of that covering the rotunda, completed during the year. The latter, however, has since been finished. It is interesting to note that this entire work was car- ried on without closing any part of the building and without injury to any of its contents. Some progress was also made in the isolation of the exhibition halls by the closing of the large openings between them, as a precautionary measure against the spread of fire. The failure to secure, last winter, an appropriation for fitting up suitable quarters for the nucleus of the national gallery of art has retarded the segre- gation and arrangement of the collection of paintings, which is now exhibited under very adverse conditions, not at all likely to attract the attention of those who might gladly contribute to this popular branch of the museum. Notwith- standing these circumstances, however, some important donations of pictures were received during the year. Mr. William T. Hyans has added to his collection of contemporary American artists paintings by Hugo Ballin, George De Forest Brush, F. 8. Church, Henry Golden Dearth, Charles Melville Dewey, Paul Dougherty, Ben Foster, Childe Hassam, Ernest Lawson, Willard Leroy Metcalf, Robert Reid, R. M. Shurtleff, 36 REPORT OF THE SECRETARY. SV John H. Twachtman, Henry Oliver Walker, Worthington Whittredge, Carleton Wiggins, Irving R. Wiles, and Frederick Ballard Williams. Among other gifts of paintings to the gallery may be mentioned the following: “Crossing the Ferry,” by Adrien Moreau, presented by Mrs. James Lowndes in memory of her father, Lucius Tuckerman; and “Indian Summer Day,” by Max Weyl, presented by 30 of his Washington friends in commemoration of the seyentieth anniversary of the artist’s birth. The collection of 13 historical marine paintings executed by the late Edward Moran during the later years of his life, have, through the courtesy of Mr. Theodore Sutro, of New York, been temporarily deposited in the gallery, of which they form a conspicuous feature. The titles of the several pieces of the series are as follows: The Ocean—The Highway of all Nations; Landing of Lief Erickson in the New World in the Year 1001; The Santa Maria, Nina, and Pinta; The Debarkation of Columbus; Midnight Mass on the Mississippi Over the Body of Ferdinand De Soto, 1542; Henry Hudson Entering New York Bay, September 11, 1609; Embarkation of the Pilgrims from Southampton, August 5, 1620; First Recognition of the American Flag by a Foreign Government, in the Harbor of Quiberon, France, February 13, 1778; Burning of the Frigate Phila- delphia in the Harbor of Tripoli, February 16, 1804; The Brig Armstrong Engaging the British Fleet in the Harbor of Fayal, September 26, 1814; Iron versus Wood—Sinking of the Cumberland by the Merrimac, in Hampton Roads, March 8, 1862; The White Squadron’s Farewell Salute to the Body of Captain John Ericsson, New York Bay, August 25, 1890; Return of the Conquerors, Typifying Our Victory in the Late Spanish-American War, September 29, 1899. By act of Congress, appreved May 22, 1908, the colossal marble statue of Washington by Horatio Greenough, completed in 1840, and since 1875 occupy- ing its well-known position in front of the main steps of the Capitol, was trans- ferred to the custody of the Smithsonian Institution. It is intended to remove this work at once to the Smithsonian building, where it will be installed for the present. In accordance with the plan proposed the year before, with the object of maintaining a* proper standard of merit in the acceptance of paintings and works of sculpture for the National Gallery of Art, a committee of five artists to act in an advisory capacity was designated in the spring of 1908. The selection of three members of the committee was requested of three leading art associations, the other two members being named by the Institution. This committee held its first meeting, for the purposes of organization and prelimi- nary considerations, at the Smithsonian Institution, on April 16, 1908. As organized, it is constituted as follows: Mr. Francis D. Millet, president; Mr. Frederick Crowninshield, representing the Fine Arts Federation, of which he is the president; Mr. Edwin H. Blashfield, representing the National Academy of Design; Mr. Herbert Adams, representing the National Sculpture Society, of which he is the president; and Mr. William H. Holmes, of the Smithsonian Institution, secretary of the committee. In May, 1908, a number of the ladies of Washington, acting on their own initiative but with the hearty concurrence of the Institution, effected an in- formal organization looking to the building up in the National Museum of a worthy collection of laces, embroideries, and other artistic objects of personal adornment and utility. Having decided that the assembling of a loan collection might best further their efforts by stimulating an interest in the subject, a working committee, with Mrs. James W. Pinchot as chairman, was immediately appointed, and during May and June a very large number of appropriate objects was brought together. The installation, made by the members of the commit- tee, filled twenty cases, which had unfortunately to be placed in the very 38 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. crowded hall occupied by the gallery of art. The character of the articles and the very effective manner in which they were arranged has, however, made this collection one of the most attractive features of the museum. The number of exhibitors is 18, while the total number of their contributions amounts to over 650. Besides laces and embroideries, the exhibit contains many fans, minia- tures, old and rare pieces of porcelain and china, enamels, ivories, silverware, and jewelry. It is hoped that this beginning, which, it is understood, will be extended during the coming winter, will go far toward accomplishing the result so much desired. ADDITIONS TO THE COLLECTIONS. The total number of accessions received during the year was 1,391, comprising approximately 219,505 specimens, of which 10,487 were anthropological, 176,263 biological, and 82,755 geological. The principal accession in ethnology consisted of about 600 extremely inter- esting objects collected among the natives of West Borneo by Dr. W. L. Abbott, and by him presented to the museum, in continuation of his many valuable contributions from the Malaysian region. Other important ethnological col- lections from the islands of the South Pacific were also obtained, among which may be mentioned material from the Philippine Islands presented by Maj. EH. A. Mearns and Capt. Jesse R. Harris, U. S. Army; and from Guam, donated by Mr. W. E. Safford. Noteworthy among the loans are a large number of art objects in metal obtained by Gen, Oliver Ellsworth Wood, U. S. Army, during a four years’ residence in Japan as military attaché, and a collection made by Senator A. J. Beveridge during an extended trip to the Orient, including the Philippine Islands, Japan, and China. As bearing upon the American Indians there were added many specimens from the region of the northern cliff dwellers of northwestern Arizona, the Taos and Zuni Indians of New Mexico, and the Iroquois of New York and Canada. A small but valuable collection illus- trating the industrial and social life of the little-known Tahltan Indians of Stikine River, British Columbia, was received from the Bureau of American Ethnology. Among the models from the Patent Office assigned to the division of ethnology were many relating to fire making, heating, cooking, illumination, eulture history, ete. To Mr. Ephraim Benguiat, of New York, the museum is under deep ebliga- tions for the addition of twenty-one objects to his already Jarge collection of Jewish religious ceremonial objects on deposit in the division of historic re- ligions. They include two finely embroidered synagogue veils, two silver-gilt breastplates of exquisite workmanship, and a silver and brass hanukah lamp of artistic design. The division of prehistoric archeology obtained from the excavations con- ducted by Dr. J. W. Fewkes at the Casa Grande ruins, Arizona, from October, 1906, to March, 1907, under a special act of Congress, an especially valuable collection, comprising stone implements, pottery, articles of shell and bone, wooden implements and timber, textile fabrics, and basket work, and a number of human skulls and parts of skeletons. Important additions were also received from other parts of this country, and from Mexico, Bolivia, Egypt, and India. The additions to the division of physical anthropology were numerous and from many sources, illustrating several races of the human family both living and extinct. Dr. W. L. Abbott also contributed a large series of specimens illustrative of the anthropoid apes and the monkeys of West Borneo and Sumatra. Many photographs, facial casts, and measurements of the Indians of North America were made in the laboratory. ; REPORT OF THE SECRETARY. 39 The division of technology was greatly enriched by the transfer from the Patent Office of many models and original examples of inventions interesting historically. The subject of firearms is most fully represented in the collec- tion, which, however, also includes printing presses, sewing machines, type- writers, electrical inventions, steam machinery, time bank locks, looms, spinning and knitting machinery, ete. Another notable accession to this division con- sisted. of about 150 pieces of apparatus devised and used by Dr. Alexander Graham Bell in his earliest telephone experiments. To the War Department, and also personally to Col. A. H. Russell, U. S. Army, the museum is indebted for several interesting examples of firearms. The collection in the division of history was increased by many valuable loans and gifts. By far the most noteworthy object among the loans was the flag which floated over Fort McHenry during its bombardment by the British fleet on the night of September 13-14, 1814, and made famous as the ‘“ Star Spangled Banner” by the verses of Francis Scott Key, an eyewitness of the fight. This flag, retained by Col. George Armistead, the commander of the fort, descended to his grandson, Mr. Eben Appleton, of New York, who has most generously allowed it to be exhibited to the public. It is much tattered and worn, and measures 52 feet .10 inches long by 27 feet 6 inches wide. A collection of 175 pieces of Lowestoft china and cut glass, used at Mount Vernon in the time of Washington, was deposited by Miss Nannie R. Heth. Among the bequests may be mentioned a gold-mounted sword and a silver pitcher presented to J.*Bank- head Magruder by citizens of Virginia and Maryland, and a gold ring given by Richard Somers to Stephen Decatur just before the heroic death of the former on the Jntrepid in the war with Tripoli in 1804. The collections of the Colonial Dames of America and of the Daughters of the American Revolution were both increased by the addition of a number of interesting objects. Miss E. R. Scidmore deposited 92 pieces of porcelains and some bronze, jade, and lacquer objects. Fifteen musical instruments were presented, mostly of primitive origin, though some are of historical interest. The principal addi- tions in graphic arts were contained among the models from the Patent Office, consisting mainly of early devices now of extreme interest in illustrating the history of photography. The department of biology received, as in former years, important contribu- tions, chiefly of mammals and birds, from Dr. W. L. Abbott and Dr. E. A. Mearns, U. S. Army, the former making collections in Sumatra and south- western Borneo, the latter in the Philippine Islands. Especially interesting for the purposes of comparison as well as for exhibition, was a series of 166 antlers and 26 scalps of the American elk, some of unusual size, from the State of Wyoming. In most of the other zoological groups the additions were extensive and representative of many parts of the world. Mr. Robert Ridgway, who spent about four months in Costa Rica collecting material and information for use in connection with his monograph on the birds of North and Middle America, brought back a large number of specimens. The Bureau of Fisheries made important transfers of both fishes and marine invertebrates, largely obtained during the explorations of the steamer Albatross in the Pacific Ocean. The collection of insects was increased by about 53,000 specimens, mostly American, although valuable contributions were also received from Europe. Through recent acquisitions, the division of mollusks now possesses authen- tically named specimens of 1,330 species of the land shells of the Philippine Islands, of which about 1,500 species have been described. The transfer to Washington from the museum of Yale University of the main part of the col- 88292—sm 1908S——4 40 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. lections of marine invertebrates obtained during the early seacoast work of the Bureau of Fisheries, and placed in the care of Prof. A. E. Verrill for study and description, has added a large number of types and a still greater number of species not previously represented in the museum. The collection in helminthology has reached a position of much practical importance, since it contains a great deal of material resulting from govern- ment investigations on the diseases of man and of wild and domestic animals. These specimens have been mainly obtained through the Marine-Hospital Servy- ice, the Bureau of Animal Industry, and the Bureau of Fisheries. The rapid growth and exceptionally fine condition of the collection are due to the efforts of representatives of the two bureaus first mentioned, who are in charge of the subject. The division of plants received a total of about 25,000 specimens, mainly collected in North and Central America, the largest accessions coming from the Department of Agriculture. Much valuable material was also derived from the explorations of Dr. J. N. Rose in the southwestern United States and northern Mexico. In the department of geology the most important accessions were of fossil invertebrates, some of which were especially large and noteworthy. Among them may be mentioned the celebrated Gustav Hambach collection, purchased by the Smithsonian Institution; the Gilbert collection of Niagaran fossils from northern Indiana; a very large series of Cambrian fossils, resulting from explorations in British Columbia and Idaho during the summer of 1907 by Secretary Charles D. Walcott; many recently described specimens deposited by the United States Geological Survey; extensive collections from the Paleozoic formations of Tennessee and Virginia, made by Doctor Bassler; and valuable exchanges from Germany and France. Of fossil vertebrates there were two especially important additions. One con- sisted of a large number of rare species of reptiles and mammals from various horizons in the United States and South America, obtained through exchange with the American Museum of Natural History; the other of the remains of several species of fossil mammals, in a more or less fragmentary condition, col- lected by Mr. Gilmore on the Smithsonian expedition to Alaska. Among other additions to the department were series of rocks and ores, mainly from the Geological Survey, a number of rare minerals, and three meteorites. CARE AND CLASSIFICATION OF THE COLLECTIONS. As collections are received at the museum they are assigned to the divisions to which they belong, and are at once labeled and recorded as to their origin, in order to insure their identity and future usefulness. The work of classifica- tion and systematic arrangement which follows requires the naming of the objects or specimens, entailing extensive studies which often result in impor- tant contributions to knowledge. The staff of employees directly connected with the handling of the collections has always been much too small to per- form this duty in a thoroughly satisfactory manner, and, while the safety of the collections has been secured by constant vigilance, it can not be said that their maintenance has been all that was desirable. These conditions may, of course, be largely attributed to the inadequate quarters afforded, but many of the diffi- culties arising from this cause might readily have been overcome with a greater force of helpers. The routine work of caring for the collections is the same from year to year, and scarcely merits repetition in this connection. There was the customary overhauling and cleaning of the dried specimens and of the drawers and cases REPORT OF THE SECRETARY. 4] containing them; the frequent poisoning of many thousands of objects subject to destruction by insect pests, and the renewal of alcohol on liquid prepara- tions, or the filling up of tanks, jars, and vials from which the preservative had more or less evaporated. The labeling and cataloguing of individual specimens as identified went on continuously, and, besides, there was the preparation of specimens for the reserve series and exhibition halls, the selection and arrange- ment of duplicates for distribution, and the identification of material received from several hundred persons, as happens every year. Of investigations conducted during the year mention may be made of de- tailed studies on the examples of basketry and traps contained in Doctor Abbott’s collection from southwestern Malaysia by Prof. O. T. Mason, who also prepared a paper entitled “ Vocabulary of Malaysian basketwork.”’ Dr. Walter Hough completed a paper on the manufacture of pulque wine and began a study of the Malaysian blowguns received from Doctor Abbott. The Jewish ceremonial objects in the National Museum were described and illustrated by Dr. Cyrus Adler and Dr. I. M. Casanowicz, and the latter has in progress an account of the collection of rosaries. In prehistoric archeology investigations were conducted by Mr. William H. Holmes and Dr. J. W. Fewkes. Dr. Ales Hrdli¢ka continued his studies on the human skeleton of different races and completed a manuscript entitled ‘“ Physiological and medical observations among the Indians of the Southwest and northern Mexico.” The principal researches based upon the collections in biology related to the following subjects: The fossil cetaceans of North America; the birds of North and Middle America; the reptiles of Japan, the Philippine Islands, and North America; the mosquitoes of North and Central America and the West Indies; the mollusks and brachiopods of the eastern Pacific Ocean collected by the Fisheries steamer Albatross; crustacea from Hast Africa and the Antarctic Ocean; the crinoid collection of the museum; the corals of the Hawaiian Islands; animal parasites; and the cacti, ferns, and other groups of plants. In addition to the above many collections were being studied for the museum by specialists attached to other institutions. The material obtained during his visit to Meteor Crater, Canyon Diablo, in May, 1907, was the subject of investigation by Dr. George P. Merrill, ac- cording to whose conclusions the well-known and peculiar depression existing there was caused by impact, presumably of a large meteor. Studies were also conducted on the meteorites in the museum collection by Doctor Merrill, assisted by Mr. Wirt Tassin. Extensive investigations were carried on by Dr. R. S. Bassler on fossil invertebrates, by Mr. J. W. Gidley on fossil mammals, by Mr. C. W. Gilmore on fossil reptiles, and by assistants of the Geological Survey on fossil plants. EXHIBITION COLLECTIONS. For some years past there has been no opportunity to increase the exhibition collections, except in a very limited way, for in nearly all the halls the cases are so crowded as to interfere with the circulation of visitors and objects can not be viewed to advantage. This does not mean, however, that these collec- tions require any less attention than before, since their maintenance demands constant oversight and labor. Moreover, changes are often made by replacing older collections with others more recently acquired and of greater present interest. From the new material obtained for the Jamestown Exposition and returned during the winter, as many articles as possible were placed on exhibition. The loan collections of General Wood and Senator Beveridge were installed in - 42 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the west hall. The Abbott cases in the gallery of the same hall were rearranged, and the entire Philippine collection, as far as it has been prepared for exhibi- tion, was placed in the gallery of the Pueblo court. The objects of Jewish religious ceremonial from Mr. Benguiat were incorporated in the collection previously received from him. A special case of Egyptian antiquities and a series of Egyptian (Coptic) textiles were arranged, and additions were made to the Bible collection. In the divisions of technology and history places were found for nearly all of the objects obtained. The interesting series of portraits of distinguished physicians, prepared for the Jamestown Exposition; was in- stalled with the collection of medicine, and the loan collection of Miss Scidmore, on the ceramic gallery. The principal additions to the exhibition series of the department of biology consisted of a skeleton of Baird’s beaked whale, a rare species, and of a group of polar bears obtained on the Ziegler arctic expedition and presented by Mrs. Ziegler. The exhibit of insects, which has been in preparation for some time, was completed to the extent permitted by the space available. In the exhibi- tion halls of the department of geology comparatively few additions or changes were made. MISCELLANEOUS. Duplicate specimens, mostly biological and geological, separated from the col- lections during the progress of investigations were disposed of to the number of about 26,000. About 14,000 of these were used in making exchanges with establishments and individuals both at home and abroad, whereby the collec- tions of the museum received new material to approximately the same extent. The other 12,000 specimens were utilized in the customary way to advance the interests of teaching, having been distributed in carefully labeled and classified sets to educational establishments throughout the country. Besides the above, over 9,000 specimens were sent to specialists for study, partly for the publica- tions of the museum and partly to aid in work carried on under other auspices. The total number of visitors to the public halls was about 300,000, a daily average of over 960 persons. This is to be regarded as a large attendance, con- sidering that the buildings are opened only on week days and during official. hours. That the National Museum is not serving its full purpose in this direc- tion, however, is evidenced by the experiences of museums in other large cities, where evening and Sunday opening insures a very much greater attendance by extending to the working people the opportunity of examining the collections. The publications of the year comprised the annual report for 1907, volumes 32 and 33, and part of volume 34 of the proceedings, five volumes of bulletins, and several papers belonging to the contributions from the national herbarium, all of which, except the annual or administrative report, are descriptive of museum collections. The library of the museum contains 33,564 volumes, 52,112 unbound papers, and a number of manuscripts, the additions during the year having consisted of 3,257 books, 4,470 pamphlets, and 247 parts of volumes. This library is a purely technical one, confined to that class of publications bearing upon the subjects covered by the museum collections, but its means of increment are so limited as to make it very difficult to keep up those studies which are essential to the classification of the collections. The appropriation for the purchase of books is entirely inadequate, and, in fact, the principal increase is effected through exchanges and gifts. During the summer of 1907 the museum, in conjunction with the Institution, participated in the Jamestown Tercentennial Exposition, and the International Maritime Exposition at Bordeaux, France, the arrangements for which were REPORT OF THE SECRETARY. 43 described in the last report. The exhibit at the former exposition was designed to illustrate the aboriginal, colonial, and national history of America, while the entire collection sent to Bordeaux by the Government was assembled, installed, and maintained under the direction of the Smithsonian Institution, © represented by Mr. W. de C. Ravenel, administrative assistant of the museum. The display at Jamestown contained many new groups and series of objects specially prepared or obtained for the purpose, which have since been incor- porated in the museum collections. Respectfully submitted. RICHARD RATHBUN, Assistant Secretary, in charge of U. S. National Museum. Dr. CHARLES D. WALCOTT, Secretary of the Smithsonian Institution. APPENDIX II. REPORT ON THE BUREAU OF AMERICAN ETHNOLOGY. Sir: I have the honor to submit the following report on the operations of the Bureau of American Ethnology for the fiscal year ending June 30, 1908: SYSTEMATIC RESEARCHES. The operations of the Bureau of American Ethnology for the fiscal year end- ing June 30, 1908, conducted in accordance with the act of Congress making provision for continuing researches relating to the American Indians under direction of the Smithsonian Institution, were carried forward in conformity with the plan of operations approved by the Secretary May 25, 1907. As in previous years, the systematic ethnologic work of the bureau was intrusted mainly to the regular scientific staff, which comprises eight members. This force is not large enough, however, to give adequate attention to more than a limited portion of the great field of research afforded by the hundreds of tribes, and the bureau has sought to supply the deficiency in a measure by enlisting the aid of other specialists in various branches of the ethnologic work. By this means it is able to extend its researches in several directions at a comparatvely modest outlay. While seeking to cover in the most comprehen- sive manner the whole range of American ethnology, the bureau has taken par- ticular care to avoid entering upon researches that are likely to be provided for by other agencies, public or private. The results sought by the bureau are: (1) Acquirement of a thorough knowledge of the tribes, their origin, relation- ship to one another and to the whites, location, numbers, capacity for civiliza- tion, claim to territory, and their interests generally, for the practical purposes of government; and (2) the completion of a systematic and well-rounded record of the tribes for historic and scientific purposes before their aboriginal characteristics and culture are too greatly modified or are completely lost. During the year researches were carried on in Arizona, New Mexico, Colorado, Texas, Minnesota, Pennsylvania, and Ontario. Investigations in the field were more than usually limited on account of the necessity of retaining nearly all of the ethnologic force in the office for the purpose of completing the revision of their various articles for the second part of the Handbook of American Indians, and in preparing additional articles on subjects overlooked in the first writing or that are based on data recently collected. The chief remained in the office during nearly the entire year, dividing his time between administrative duties and ethnologic investigations and writing. The completion of numerous articles for the second part of the Handbook of American Indians, the revision of reports and bulletins, and the examination of various manuscripts submitted for publication especially claimed his attention. Aside from these occupations, his duties as honorary curator of the division of prehistoric archeology in the National Museum and as curator of the National Gallery of Art absorbed a portion of his time. During the year much attention was given to the collections of the division of prehistoric archeology in the National Museum, especially to their classification with the view of removal in 44 REPORT OF THE SECRETARY. 45 the near future to the new National Museum building. In the same connection the chief carried forward the preparation of his Handbook on the Stone Imple- ments of Northern America. In October the chief was called on to make an Official visit to the Jamestown Exposition for the purpose of examining the exhibits of the Institution and superintending necessary repairs. In April he was assigned the very pleasant duty of visiting Detroit, Mich., in company with the Secretary, for the purpose of inspecting the great collection of art works recently presented to the Smith- sonian Institution by Mr. Charles L. Freer. On this occasion he availed himself of the opportunity of examining the interesting collections of art and ethnology preserved in the Detroit museum of art. In June the chief was selected to represent the Institution as a member of the delegation of Americans appointed by the Department of State to attend the Pan- American Scientific Congress to be held in Santiago, Chile, beginning December 25, 1908, and he began at once the preparation of a paper to be read before the congress, the subject chosen being “The Peopling of America.” At the beginning of the year Mrs. M. C. Stevenson, ethnologist, was in the office engaged in preparing reports on her recent researches in the field. Her work at Taos, Santa Clara, and other Rio Grande pueblos was not so well ad- vanced as to admit of final treatment, but progress was made in the classification and elaboration of the data thus far collected. Principal attention was given while in the office to the completion of papers relating to the medicinal and food plants of the Zuni Indians, the pantheon of the Zufi religious system, the symbolism of Pueblo decorative art, and the preparation of wool for weaving among the Pueblo and Navaho tribes. On May 28 Mrs. Stevenson again took the field in the Rio Grande Valley with the view of continuing her investigations among the Taos, Santa Clara, San Ildefonso, and other Pueblo groups, and at the close of the year she was able to report satisfactory progress in this work. Mr. F. W. Hodge, ethnologist, was engaged during the year on the Handbook of American Indians, the editorial work of which has proved extremely arduous and difficult. This work is in two parts: Part 1, A-M, was issued from the press in March, 1907, and the edition became practically exhausted in a few months. Indeed the demand for the work has been so great that the bureau has found it impossible to supply even a third of the copies requested by cor- respondents. The quota under control of the Superintendent of Documents also was soon exhausted, necessitating the reprinting of an edition of 500 copies (the limit allowed by law) in order to fill the orders received. The main body of part 2 was in type at the close of the fiscal year, and about 250 pages had been finally printed, though progress in proof reading was ex- ceedingly slow on account of the great diversity of the topics treated and the difficulty of preparing or of bringing to date numbers of articles relating often to obscure tribes and subjects. It is expected that the second part will be ready for distribution during the coming winter. In the editorial work Mr. Hodge had the assistance of all the members of the staff of the bureau, and especially of Mrs. Frances S. Nichols, who devoted her entire time to the task. In addition the following specialists rendered all possible assistance in their particular fields: Mr. S. A. Barrett, of the University of California; Rev. W. M. Beauchamp, of Syracuse; Dr. Franz Boas, of Columbia University ; Dr. Herbert E. Bolton, of the University of Texas; Mr. D. I. Bushnell, jr.; Dr. Alexander F. Chamberlain, of Clark University; Mr. Stewart Culin, of the Brooklyn Institute Museum; Dr. Roland B. Dixon, of Harvard University ; Dr. George A. Dorsey, of the Field Museum of Natural History; Mr. J. P. 46 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Dunn, of Indianapolis; Mr. Wilberforce Eames, of the New York Public Library ; Lieut. G. T. Emmons, U. S. N.; Dr. Livingston Farrand, of Columbian University ; Miss Alice C. Fletcher, of Washington; Mr. Gerard Fowke, of St. Louis; Mr. Merrill E. Gates, of the Indian Rights Association; Mr. William R. Gerard, of New York; Dr. P. E. Goddard, of the University of California ; Dr. George Bird Grinnell, of New York; Mr. Henry W. Henshaw, of the United States Biological Survey; Dr. Edgar L. Hewett, of the Archeological Institute of America; Dr. Walter Hough and Dr. AleS Hrdlicka, of the United States National Museum; Dr. William Jones, of the Field Museum of Natural History ; Dr. A. lL. Kroeber, of the University of California; Mr. Francis La Flesche, of Washington; Dr. A. B. Lewis, of the Field Museum of Natural History ; Dr. Charles F. Lummis, of Los Angeles; Dr. O. 'T. Mason, of the United States National Museum; Mr. Joseph D. McGuire, of Washington; Rey. Leopold Oster- mann, of Arizona; Mr. Doane Robinson, of the South Dakota Historical So- ciety ; Mr. Edward Sapir and Mr. Frank G. Speck, of the University of Pennsyl- vania; Mr. C. C. Willoughby, of the Peabody Museum, Cambridge; and Dr. Clark Wissler, of the American Museum of Natural History. I take this occa- sion to express the appreciation of the bureau for the valuable aid so gener- ously rendered by these students, without which it would not have been pos- sible to make the work either as complete or as accurate as it is. Throughout the year Mr. James Mooney, ethnologist, remained in the office, occupied either in the preparation of articles intended for the second part of the Handbook of American Indians or in preparing answers to ethnologic in- quiries made by correspondents of the bureau. His principal work for the handbook was an elaborate and detailed study of the numerical strength of the aboriginal population north of Mexico from the time of their first contact with the whites. This important foundation study of American ethnology has never before been undertaken in a systematic and comprehensive manner, and the result proves of much scientific interest. Contrary to the opinion frequently advanced on superficial investigation, the Indians have not increased in number since their first contact with civilized man, but have decreased by fully two-thirds, if not three-fourths. California alone, the most populous large section during the aboriginal period, contained probably as many Indians as are now officially recognized in the whole United States. The causes of decrease in each geo- graphic section are set forth in detail in chronologic sequence in Mr. Mooney’s study. - During the year Dr. John R. Swanton, ethnologist, was occupied entirely with work in the office, principally in connection with the Indian languages of Louisiana and Texas. He finished the analytic dictionary of the Tunica language and compiled similar dictionaries of Chitimacha, Attacapa, and Ton- kawa. All the extant Comecrudo and Cotoname material, as well as the material pertaining to related tribes contained in Fray Bartholome Garcia’s Manual para administrar los sacramentos (Mexico, 1760), was similarly arranged, and in addition a comparative vocabulary was constructed which embraces the last- mentioned data as well as the Karankawa and Tonkawa. During the months of May and June another dictionary was prepared, embracing all the Biloxi linguistic material collected by Doctor Gatschet and Mr. J. O. Dorsey in 1886, 1892, and 1893. The material in this last work is exceptionally full and com- plete. The Comecrudo and Cotoname, the material extracted from Garcia’s catechism, and the Biloxi, are nearly ready for the press. The languages referred to above, with the addition of the Natchez, include practically all of those in the eastern and southern United States that are in immediate danger of extinction, The information regarding most of them is very limited, and REPORT OF THE SECRETARY. 47 in order that the precious material may not by any misadventure be destroyed, it should be published at an early date. Besides work strictly linguistic, Doctor Swanton had in hand a paper on the tribes of the lower Mississippi Valley and neighboring coast of the Gulf of Mexico. This can not be completed, however, until additional researches among the tribes in question have been made. Dr. J. Walter Fewkes, ethnologist, spent July and August largely in the preparation of his report on the excavation and repair of the Casa Grande ruins, Arizona, during the preceding fiscal year, which was printed in the quar- terly issue of the Smithsonian Miscellaneous Collections. Doctor Fewkes was in the Southwest from October 24, 1907, to the end of the fiscal year. From November to the middle of March he was in charge of the excavation and repair work at Casa Grande, for which there was available the sum of $3,000, appropriated by Congress, to be expended under the direction of * the Secretary of the Smithsonian Institution. The season’s operations at Casa Grande began with excavations in Compound B, the second in size of the great compounds which form the Casa Grande group. This was found to be a rec- tangular area inclosed by a massive wall. Within this are many buildings, the majority of which were once used for ceremonial and communal purposes. On excavation it was ascertained that the two great pyramids in Compound B are terraced and that they contain seven distinct floors. The remains of small, fragile walled houses, resembling Pima jacales, were found upon the tops of these pyramids, and in the neighboring plazas subterranean rooms, with cemented floors and fireplaces, were unearthed under the massive walls. This compound was thoroughly repaired with Portland cement, and drains were built to carry off the surface water. A roof was built over the subterranean room, the de- eayed upright logs that once supported the walls were replaced with cedar posts, and other steps were taken for the permanent preservation of these interesting remains. . The walls of Compounds C and D were traced throughout; in the middle of the latter compound is a large building, the ground plan of which resembles Casa Grande. The most extensive structure excavated at Casa Grande is a clan house, a building 200 feet long, with 11 rooms whose massive walls inclose a plaza. In the middle of the central room of this cluster there is a seat, called by the Pima Indians “the seat of Montezuma.” On the north side there is a burial chamber, the walls of which are decorated in several colors. This room contains a burial cyst in which was found the skeleton of a priest surrounded by ceremonial paraphernalia. The bases of the walls of the clan house were protected with cement, and drains were built to carry off water. For the con- venience and information of visitors all the buildings excavated were appro- priately labeled, and placards containing historical data were posted at various points. Although the appropriation was not sufficient for completing the work of excavation and repair of the Casa Grande group, the amount available made it possible to present a type ruin showing the general character of the ancient pueblo remains in the Gila and lower Salt River valleys. At the close of the work at Casa Grande, Doctor Fewkes was able to make a comparative study of the mounds in the neighborhood of Phoenix, Mesa, and Tempe, and also of the ancient habitations on the Pima Reservation. Several large ruins in the vicinity of Tucson were visited, and an extensive ruin, known to the Pima and Papago as Shakayuma, was examined near the northwestern end of the Tucson Mountains. Several ancient reservoirs, now called ‘‘ Indian tanks,” situated east of Casa Grande, along the trail of the early Spanish dis- coverers, were identified by their historic names. In a reconnoissance down 48 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. San Pedro River to its junction with the Gila a number of ruins were discovered on both banks of the San Pedro and of Arayvaipa Creek. A visit was also made to the imposing cliff houses, near Roosevelt dam, lately declared national monu- ments by executive proclamation. Ruins near the mouth of Tonto River were likewise examined. At the close of April, by direction of the Secretary of the Smithsonian Insti- tution, Doctor Fewkes proceeded to the Mesa Verde National Park in southern Colorado, where he took charge of the excavation and repair work of the celebrated Spruce-Tree House. This ruin was thoroughly excavated and its walls were repaired and put in good condition, in order that it might serve as a type ruin of the cliff dwellings of the Mesa Verde National Park. One hun- dred and fourteen rooms and eight kivas were excavated; two of the kivas were furnished with roofs reconstructed like aboriginal kiva roofs in Peabody House; an approach to the ruin was graded and drained, and labels were placed at convenient points for the information of visitors. Several large rooms, hitherto unknown, were unearthed, and the structure of the kivas was carefully studied. In order to deflect the water that fell on the ruin from the rim of the canyon, causing great damage, a channel 300 feet long was blasted out of the rock on top of the cliff. Two collections of considerable size were made, one at Casa Grande and the other at Spruce-Tree House. The former includes many rare and several unique objects that shed much light on our knowledge of the culture of the prehistoric inhabitants of the Casa Grande of the Gila; the latter includes skulls, pottery of rare forms and decoration, stone and wooden implements, basketry, cloth and other woven fabrics, sandals, and bone implements of various kinds. The objects from the Spruce-Tree House will be the first large accession by the National Museum of collections of objects from the Mesa Verde ruins. Doctor Fewkes completed his work at Spruce-Tree House on June 27. Mr. J. N. B. Hewitt, ethnologist, remained in the office during the entire year. Much time was devoted to the collection and preparation of linguistic data for a sketch of Iroquoian grammar as exemplified by the Onondaga and the Mohawk, with illustrative examples from the Cayuga, Seneca, and Tuscarora dialects, for the forthcoming Handbook of American Indian Languages. In pursuing these studies Mr. Hewitt was fortunate in obtaining data which enabled him to supply translations of a number of very important archaic political and diplomatic terms in the native texts embodying the founding, constitution, and structure of the government of the League of the Iroquois. The meanings of these terms are now practically lost among those who speak the Iroquoian languages. As time permitted, these texts were studied and annotated for incorporation in a monograph on the above-mentioned phases of the government of the League of the Iroquois, a work which hitherto has not been seriously undertaken because of its cumbrousness, its extremely com- plicated character, and the great difficulty in recording the native material expressed in tens of thousands of words. In addition to these studies Mr. Hewitt prepared for the Handbook of American Indians descriptions of the early mission towns and villages of the Iroquois tribes, brief biographical sketches of Red Jacket (Shagoyewatha) and Thayendanegen (Joseph Brant), and wrote several articles on Iroquois subjects. From time to time Mr. Hewitt was called on to assist also in preparing data of an ethnologic nature for replies to correspondents of the office. During the greater part of the year Dr. Cyrus Thomas, ethnologist, devoted attention chiefly to the preparation of the catalogue of books and papers relat- ing to the Hawaiian Islands. After the number of titles had reached about REPORT OF THE SECRETARY. 49 4,000 the Institution’s committee on printing suggested some modification of the plan of the catalogue which necessitated a change in the form of the titles of periodicals—about one-third of the entire list. In connection with this work Doctor Thomas made supplementary examinations of works in the libraries of Washington, especially the Library of Congress and the libraries of the Department of Agriculture and the National Museum, and in those of Boston and Worcester. He carried on also, so far as time would permit, the prepara- tion of subject cross-references. Doctor Thomas continued to assist in the preparation of part 2 of the Handbook of American Indians, furnishing a number of articles, especially biographies, and assisting the editor in the reading of proofs, particularly with the view of detecting omissions, lack of uniformity in names, ete. SPECIAL RESEARCHES, In addition to the systematic investigations conducted by members of the bureau staff, researches of considerable importance were undertaken by col- laborators of distinction. Dr. Franz Boas, honorary philologist of the bureau, practically completed his work on the Handbook of American Indian Languages, and at the close of the year a large part of the manuscript of volume 1 had been submitted to the bureau. This volume comprises an extended introduction by Doctor Boas, and a number of studies of selected languages, by special students, designed to illustrate the introductory discussion. With the approval of the Secretary the first of these studies—the Athapascan (Hupa)—by Dr. Pliny E. Goddard, was submitted to the Public Printer, with the view of having it placed in type for the use of Doctor Boas in preparing other sections for the press. The highly technical nature of the typesetting made this procedure necessary. Field work required in completing the handbook was limited to a brief visit by Doctor Boas to the Carlisle Indian School in Pennsylvania and to certain investigations among the remnant of the Tutelo tribe in Ontario, conducted by Mr. Leo J. F. Frachtenburg. Dr. Herbert E. Bolton continued his studies relating to the tribes of Texas, so far as the limited time at his disposal permitted, but he was not able to submit the first installment of manuscript at the close of the year, as was expected. An outline of the work undertaken by Docton Bolton was presented in the last annual report. During the year for the first time the study of native Indian music was se- riously taken up by the bureau. Miss Frances Densmore was commissioned to conduct certain investigations relating to the musical features of the grand medicine ceremony of the Chippewa on the White Earth Reservation, Minn. The phonograph was employed in recording the songs, and after the close of the ceremony and visits to other Indian settlements Miss Densmore was called to Washington, where she reproduced her records and engaged successfully in recording songs of members of the various Indian delegations visiting the capital. A preliminary report was submitted by Miss Densmore, with the understanding that it is not to be printed until additional researches have been made in the same and related fields. The collection of phonographic records thus far obtained is extensive and the investigation promises results of excep- tional interest and scientific value. During the year arrangements were made to accept for publication as a bulletin of the bureau a report on certain explorations among the ancient mounds of Missouri by Mr. Gerard Fowke. These explorations were under- taken under the auspices of the Archeological Institute of America, but form an appropriate addition to the work of the bureau in this particular field. A 50 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. part of the collections made by the explorer was presented to the National Museum by the Archeological Institute. It is proper that appreciation of the gratuitous labors of Dr. Nathaniel B. Emerson in editing and proof reading his memoir on the “ Unwritten literature of Hawaii,” accepted for publication during the year as Bulletin 38, and also the important part taken in the preparation of the “ List of works relating to Hawaii,” assigned to Bulletin 41, by Mr. Howard M. Ballou, should be ac- knowledged in this connection. PRESERVATION OF ANTIQUITIES, The bureau maintained its interest in the antiquities of the country during the year. Bulletin 35, The Antiquities of the Upper Gila and Salt River Val- leys in Arizona and New Mexico, by Dr. Walter Hough, was issued. ‘The $3,000 appropriated by Congress for the excavation, repair, and preservation of Casa Grande ruin in Arizona, and the $2,000 allotted by the Interior Department for similar work among the cliff dwellers of the Mesa Verde National Park in Colorado, were expended under the immediate auspices of the Smithsonian Institution, the execution of the work being intrusted to Dr. J. Walter Fewkes, ethnologist, as elsewhere reported. Progress was made in the preparation of a catalogue of antiquities, and valu- able data in this field were collected by Mr. W. B. Douglas, of the General Land Office, whose official labors recently brought him into contact with the antiqui- ties of southeastern Utah. During the year, by executive proclamation, several additions were made to the growing list of national monuments. Three of these are of especial archeo- logical interest, namely, the Tonto National Monument, situated in the Tonto drainage basin, Gila County, Ariz., including two cliff dwellings not yet reported on in detail; the Gila Cliff Dwellings National Monument, in the Gila National Forest in New Mexico, comprising the group of cliff dwellings described in the bureau’s Bulletin 35 (p. 30), and the Grand Canyon National Monument, com- prising within its limits the Grand Canyon of the Colorado, in which are situ- ated innumerable antiquities, including cliff dwellings, pueblos, dwelling sites, and burial places. The cliff dwellings are found mainly in the walls of the canyon, while the other remains are scattered along the margins of the plateaus. COLLECTIONS, The collections acquired during the year and transferred according to custom to the National Museum are not equal in importance to those of the preceding year. They comprise 14 accessions, the most noteworthy being collections of stone relics from the Potomac Valley, by G. Wylie Gill and W. H. Holmes; a collection of ethnologic material obtained from the Tahltan Indians of British Columbia, by Lieut. G. T. Emmons, U. 8S. Navy; a collection of stone implements from Washington State, by C. W. Wiegel; and relics and human bones from ancient burial places in Missouri, by Gerard Fowke. PUBLICATIONS. During the year progress was made on the Handbook of American Indians, and on the Handbook of American Indian Languages, as mentioned on other pages. The edition of the twenty-fifth annual report, containing papers by Dr. J. Walter Fewkes on his explorations in the West Indies and in Mexico, was received from the Public Printer in September; Bulletin 30, the Handbook of American Indians, part 1, in March; Bulletin 33, Skeletal Remains Suggesting or Attributed to Early Man in America, in November; and Bulletin 35, REPORT OF THE SECRETARY. 51 Antiquities of the Upper Gila and Salt River valleys in Arizona and New Mexico, in February. The twenty-sixth annual report was in the bindery at the close of the year. At that time Bulletin 34, Physiological and Medical Observations among the Indians of Southwestern United States and Northern Mexico, by Dr. AleS Hrdli¢ka, was for the main part in stereotype form, while Bulletin 88, Unwritten Literature of Hawaii, by Dr. Nathaniel B. Emerson, the manuscript of which was transmitted to the Public Printer early in the year, was largely in pages. The manuscript of Bulletin 39, Tlingit Texts and Myths, by Dr. John R. Swanton, and of a section of Bulletin 40, Handbook of the American Indian Languages, was also transmitted to the Public Printer. The distribution of publications was continued as in former years. Fifteen hundred copies of the twenty-fifth annual report, and a like number of Bulletins 383 and 85, were distributed to the regular recipients, most of whom sent their own publications in exchange. There was a greater demand for the publications of the bureau than during previous years. The great increase in the number of public libraries and the multiplication of demands from the public generally, resulted in the almost immediate exhaustion of the supply (3,500 copies) allotted to the bureau. During the year the bureau received from outside sources a number of the earlier issues of its reports and was thus able to respond to numerous requests from Members of Congress for complete sets, except the first annual report, the edition of which is entirely exhausted. About 1,000 copies of the twenty-fifth annual report, as well as numerous copies of the other annuals, bulletins, and separate papers, were distributed in response to special requests, presented largely through Members of Congress. LINGUISTIC MANUSCRIPTS. The archives of the bureau contain 1,659 manuscripts, mainly linguistic. The card catalogue of these manuscripts begun in the preceding year and completed during the year comprises more than 14,000 titles, which give as completely as possible the stock language, dialect, collector, and locality, as well as the character and the date, of the manuscript. While it was not pos- sible in every instance to supply all the information called for under these heads, the catalogue is found to meet all ordinary requirements of reference. There were several important additions to the collection of manuscripts during the year, mainly through purchase. Prominent among linguistic students who have recently submitted the results of their labors to the bureau are Mr. Albert B. Reagan, who is making important investigations among the Hoh and the Quileute Indians of Washington, and Mr. J. P. Dunn, a leading authority on the Algonquian languages of the Middle West. Owing to the number and bulk of the bureau’s manuscripts, it is not possible to place them all in the fireproof vault, and about half the material is arranged in file cases, convenient of access. These manuscripts may be classified as: (1) dictionaries and vocabularies; (2) grammars, and (3) texts. By far the greater number are vocabularies, of varying length and completeness. Usually they give the Indian name and English equivalent without recording the deriva- tion or current usage of the term given. Of greatest value are the several dictionaries, among them a Dhegiha (Siouan) dictionary prepared by the late Rey. J. Owen Dorsey, containing about 26,000 words; the Peoria dictionary of Dr. A. 8. Gatschet; an Abnaki dictionary in three thick folio volumes, prepared by the Rey. Eugene Vetromile, by whom it was deposited with the bureau; and a dictionary, in five volumes, of the Choctaw tongue, by the Rey. Cyrus Byington. 52 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. ILLUSTRATIONS. In the division of illustrations 2,810 photographic prints were made for use in illustrating publications, for correspondents, and for the cataloguing of negatives, which is now well in hand. A large number of prints of Indian subjects were acquired by purchase and filed for reference and for future use as illustrations. The photographic work included the making of 366 negatives, 310 of these being portraits of Indians of visiting delegations. The importance of the collection of portraits thus being brought together is indicated by the list of tribes represented, and is especially emphasized by the fact that these delegations usually consist of the best representatives of the tribes and hence may serve as types of the race. The negatives are 63 by 8% inches in size. The tribes represented are as follows: Apache (Apache proper, Arizona and New Mexico; Chiricahua band. held as prisoners in Oklahoma); Arapaho of northern Wyoming and southern Oklahoma; Cheyenne of northern Montana and southern Oklahoma; Chippewa (White Earth, Red Lake, and Mille Lac bands) ; Choctaw, Coeur d’Aléne; Creek, Crow, Eskimo of Labrador; Flathead, Iowa, Kickapoo, Omaha, Osage, Oto, Pawnee, Pima, Potawatomi, San Blas (Argona tribe, Rio Diablo, south of Panama); Shoshoni, Sioux, Teton Sioux (including Brulé, Ogalala, Hunkpapa, and Sihasapa), and Yankton. LIBRARY. Good progress was made in accessioning and cataloguing the newly acquired books, pamphlets, and periodicals. In all there were received and recorded during the year 392 volumes, SOO pamphlets, and the current issues of upward of 500 serials, while about 600 volumes were bound at the Government Printing Office. The library now contains 14,022 volumes, 10,600 pamphlets, and several thousand numbers of periodicals relating to anthropology, most of which have been received by exchange. The purchase of books and periodicals has been restricted to such as relate to the bureau’s researches. Respectfully submitted. W. H. HotmMEs, Chief of Bureau. Dr. ‘CHARLES D. WALCOTT, Secretary of the Smithsonian Institution, APPENDIX ITI. REPORT ON THE INTERNATIONAL EXCHANGES. Sir: I have the honor to submit the following report on the operations of the international exchange service during the fiscal year ending June 30, 1908: In addition to carrying out the second term of the clause of the will estab- lishing the Smithsonian Institution—‘the diffusion of knowledge among men ”—which was the occasion for the inauguration of this work in 1850, the ever-increasing usefulness of the system of international exchanges continues an important aid in the advancement of scientific knowledge throughout the world. Hundreds of thousands of works, containing, among other matters of importance, the details of the latest discoveries and inventions, are annually brought to this country, while a knowledge of everything of like nature originating here is, through this medium, disseminated abroad. The growth of this system to its present comprehensive proportions has been made possible through the action of Congress and of our Government in negotiating treaties to place the exchange of government and scientific and literary publications upon a definite, legal, international footing. A resolution, approved March 2, 1867, provides that 50 copies of all documents printed by order of either House of Congress, and also that 50 copies of all publications issued by any department or bureau of the Government shall be placed at the disposition of the Joint Committee on the Library for exchange with foreign countries through the agency of the Smithsonian Institution. By a subsequent resolution, which was approved March 2, 1901, the number of sets of documents to be exchanged with foreign countries was increased to 100—the results of this governmental exchange through the Institution to inure to the benefit of the Library of Congress. In addition to these two acts of the Congress of the United States, an im- portant convention was signed at Brussels in 1886, which resulted for this country in a treaty for the international exchange of official documents and scientific and literary publications, ratified by the Senate and proclaimed by the President in 1889. Many nations not parties to this convention have since accepted its provisions and are conducting international exchange bureaus. The appropriation by Congress for the service during the fiscal year ending June 30, 1908, was $32,200 (an increase of $3,400 over the preceding year), and the sum collected on account of repayments was $3,352.69, making the total available resources for international exchanges $35,552.69. Through this increase in the appropriation it was possible to inaugurate a system of work which has long been in mind—that of actively seeking returns from foreign countries for the exchanges sent to them by this Government and its depart- ments and bureaus. Heretofore, although there has been some effort on the part of the Institution to secure proper returns, and the bureaus themselves have taken the matter up from time to time, the United States has been almost entirely dependent upon the good will of foreign establishments; but in Feb- ruary, 1908, an active and definite campaign was entered upon to secure reciprocal returns, the exchange bureau doing the work and bearing the ex- pense. The result has already been more than satisfactory, but the effort is so recent that its full fruition could hardly be expected within the year. A number 58 54 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. of most gratifying acknowledgments have been received from various depart- ments of the Government regarding this new work. The transmission of packages has been much more prompt during the past twelve months than during any like. period in the history of the service. The increased efficiency that this indicates is due in great measure to the practice inaugurated during the year of making shipments to all countries at least once a month. In carrying out this plan it has been necessary to expend consider- ably more for freight and postage than during previous years, but as the good results have been so obvious frequent shipments will continue to be made so long as the appropriations permit of the extra expense. A communication was received during the year from the Russian Commission of International Exchanges, requesting, on behalf of the Library Commission of the Douma, that the United States Government enter into an exchange of par- liamentary publications with Russia. The matter was taken up with the Libra- rian of Congress, and while it was considered that the exchange would be a most desirable one, in the absence of legislation setting apart a copy of the Congres- sional Record for this purpose permanent arrangements could not at once be made. The Librarian of Congress, however, succeeded in obtaining a copy of the Record for this purpose, and the interchange of parliamentary publications was entered into with Russia in March. As such information as the Congres- sional Record contains would be of more value if received without delay, send- ings were made directly by mail, and this practice will be followed in the future. It may be added in this connection that the French Chamber of Deputies has also made a request, through the Department of State, for the exchange of parliamentary documents, and that the matter was communicated to Congress by the department during the last session. No action was taken, however, though it is understood that the subject will be given consideration at a future date. At the time the convention for the exchange of official documents and scien- tific and literary publications was entered into at Brussels, in 1886, an agree- ment was also made between the United States and several other countries for the immediate exchange of official journals, ete., but in the absence of the nec- essary legislation by Congress no steps have been taken by the Institution to carry this agreement into effect. As the subject has now been brought to the attention of Congress, a sufficient number of copies of the Congressional Record may be set aside for this purpose. I recommend, however, that the Smith- sonian Institution seek to execute this agreement by legislation. The Kingdom of Servia, which was one of the signatories to the Brussels con- vention of 1886, has never established a bureau of exchanges, and it has been necessary to forward transmissions to correspondents in that country through some other medium. Article I of the convention provides that each of the con- tracting States shall designate an office to take charge of the exchanges, and with a view to having such a bureau established in Servia the good offices of the Department of State have been solicited in bringing the matter to the attention of the Servian officials. While the number of publications at present exchanged between the United States and Servia is not large, it is hoped that if Servia will designate some office to take charge of the work it will result in a fuller interchange of publications between the two countries. The arrangement of details concerning the shipment of a full set of govern- ment documents to China having finally been perfected, the first consignment, consisting of 16 cases, was, under date of February 20, 1908, forwarded to the American-Chinese publication exchange department of the Shanghai bureau of foreign affairs—the depository designated by the Government of China. It is most gratifying to the Institution that after so many years of almost constant endeavor on its part this interchange of documents has at last been effected. REPORT OF THE SECRETARY. 55 As a result of correspondence between the Smithsonian Institution and the diplomatic envoys from the Republic of Liberia, regarding the establishment of a bureau of international exchanges in that country and the interchange of offi- cial documents between the Government of Liberia and the United States, the department of state at Monrovia has been designated to act as the exchange intermediary between the two countries, and the proposition to exchange official publications has been accepted by the envoys. A partial set of United States Government documents is being made up by the Library of Congress, and will be forwarded to Liberia as soon as received at the Institution. Negotiations conducted through diplomatic channels have enabled the United States to enter into arrangements with the Government of Montenegro to ex- change official documents, and the first sending of a partial set was made to that country during September, 1907. The documents are deposited in the ministére princier des affaires étrangéres de Monténégro, Cetinje. A service of international exchanges having been established under the direc- tion of the Biblioteca Nacional at Santiago, Chile, the Chilean exchange agency has recently been transferred from the Universidad de Chile to that library. The Institution desires to record its grateful acknowledgment of the services rendered by the university during the past twelve years in the distribution of packages in Chile. At the request of the Museo Nacional at San Salvador, consignments for dis- tribution in that country will henceforth be sent in care of the ministerio de fomento at San Salvador. The Institution has not yet been successful in prevailing upon an establish- ment in Korea to act as the exchange medium between that country and the United States. Transmissions to Korea, which were interrupted during the late Russo-Japanese war, Have therefore not been resumed. Through the wrecking of the steamship Newark Castle off the coast of south- east Africa, the Institution suffered the loss of several packages of exchanges destined for correspondents in Mauritius. So far as reported to this office, this is the only instance during the past year in which packages were lost while in transit. I am pleased to say that upon presenting the facts to the senders, dupli- cate copies of all the lost publications were furnished for transmission to Mauri- tius. ; In continuation of the work inaugurated a few years ago, further steps have been taken to reduce to a minimum the danger in case of fire in the rooms occupied by the bureau. As a part of the plan of the Institution to divide the basement of the building into several fireproof sections, metal doors were placed in the exchange office and in the hall immediately adjoining. Several portable fire extinguishers have also been procured and placed where they may be most accessible in case of need. INTERCHANGE OF PUBLICATIONS BETWEEN THE UNITED STATES AND OTHER COUNTRIES. The total number of packages handled by the international exchange service during the past year was 203,098, an increase over the number for the preceding year of 18,268. The weight of these packages was 435,285 pounds, a decrease from 1907 of 34,251. This decrease in the weight is largely due to the reduction in the size of the government documents received for transmission. It may be added that this circumstance has resulted from the executive order issued January 20, 1906. This order, in brief, provides for the appointment by the heads of departments of advisory committees on printing and publication, whose duty shall be to see that unnecessary matter is excluded from reports and publi- eations; to do away with the publication of unnecessary tables, and to require 88292—sm 1908——5 56 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. that statistical matter be published in condensed and intelligible form; to pre- vent duplication of printing by different bureaus; to exclude unnecessary illus- trations from department documents, ete. The statement which follows shows in detail the number of packages ex- changed between the United States and other countries: Statement of packages received for transmission through the International Exchanges during the year ending June 30, 1908. Packages. Packages. Country. Country. For. From. For. From. INIDYSSIMIG eset cece soe cise s oe ql eens Gibraltar cssasccsencecesce cies 13 it IAN COTS soas.ccce see sien ese 118 Ady | WGOldi CoOastecs--cecceciecec= see Biiisteeceeme ANP Ola seceesescaece see ee 3 AUN Greist ass Save eae) Plea Go lbeetensees INSTARRTE) Ssogconcedenneo50500n Be |lcossossase Great Britain and Ireland...) 20, 562 8, 666 PATA Uacitsiwoce cian. cetie eos 28) | pecemesees Greeceiete-ccceohesccwarecens h lae3 5 (ee PAT CONbIMN A oe coma sosecinsi 8, 044 AOS a nGreeniland na seecesaeetae Sel Ee seer ATIStHia-MUNPAaTyicease sacs sas 7,490 224) Guadeloupeepcsecess-se-cece> 1) ES pee ee IAZOLES Sacces scieuicesiceseisioas' ss 98 Vo conaso0bs Guatemalanes-ssoseese-ssce= ee 220 I Paeneas or IBahamMas!s.-passccessicccecocs AGT evesteretoe Veith ee ost cease sewaiseceeeee nt) 0 eee eee BarbadOsSescecceseccsisssiece OP bgncconeec | Hawaiian Islands ..........- OTE ie TB AS UNOIGING aoosoooeadcusosne ee BS See Hon cums eeeeseere == seer AUT ES ed BeiPayauos ceca cee selec sees acces 1B} WedSocosoac Honsikoneeeececessee sees eee TA Se tet aes 3 Beleiumeren eee eaisccre ea 4,184 PAHO Il WoT. .sogssoecos cossaeeose ANT A| sal sao IBCLINUGAS eo ewieseeaeeeesccices Bhs) losogaaoaes INI ss. ctcocssae seseeesces 2, 495 121 Bismarck Archipelago...-.. ne Resear lelbaliyaaeesemencer seeeee nce ces 6,849 1, 287 LO har eS sepoaoae See SceesaSsee ‘ IPAS \ecascooons JAMAICH 5b ectanonesee sees 220M areeekteaee IBOMCOs ..- coo ecc ciceimasmeiesne i \pelstssectstcie's JAPAN seo sssccsosaseies cee 3, 010 27 IBTAZ pepe er ese aes see eres 25 O00 6764 |'TAVaisasacccasme-scereeseciccce 243 169 IBTiLiISheAMMenicarencseeeeeeees 6, 604 704 || Kongo Free State. ........-.- oA eT ee BritishPeurm pereeeeee-eeeeee Uhl Raceneeeta IOVS: wecsez vos cw sccacenesisiss FU Ieee British East Africa..-----..- UD edosenasct WAP OSecsesoanc aie secs cisiseene 1 eon BritiShiG ui snes seen eee Gil laaccoseues iberidms.s Janse cgaeeecee sects 6D Pes ereoce British Honduras.........-- GO eacosasoce Lourenco Marquez ......---. 81 38 Bulvarigccetmccnisccs exe scee 166 140 Meee mip ure sae eeeriaaaseeterercs Sh Maasscee es Cananyislandsee2oseseeeeeee AD: | eispeterere islet = Madagascar saac Presented at the New York meeting (December, 1908) of The American Society of Mechanical Engineers. 117 118 ANNUAL REPORE SMITHSONIAN INSTITUTION, 1908. surfaces, and are also often balanced so as to be slightly heavier than the air in which they move, employing the propeller thrust and rudder surfaces to control the altitude. I. ABROSTATION. Captive and free balloons, with the necessary apparatus and devices for operating the same, have been for many years considered an essen- tial part of the military establishment of every first-class power. They played a conspicuous part in the siege of Paris, and were often valuable in our own civil war. The construction and operation of aerostats are too well understood to need further attention here. SUCCESSFUL MILITARY DIRIGIBLE BALLOONS. France. Two types of dirigible balloons have been used in the French army— first, the Patrie, and, second, the Ville de Paris. The Patrie was developed by Jullot, an engineer employed by the Lebaudy Brothers at their sugar refinery in Paris. A history of his work beginning in 1896 is fully given in La Conquéte de l’Air. THE PATRIE. The Patrie, the third of its type, was first operated in 1906. The gas bag of the first balloon was built by Surcouf at Billancourt, Paris. The mechanical part was built at the Lebaudy sugar refinery. Since then the gas bags have been built at the Lebaudy balloon shed at Moisson, near Paris, under the direction of their aeronaut, Juchmés. The gas bag of the Patrie was 197 feet long, with a maximum diameter of 33 feet 9 inches, situated about two-fifths of the length from the front; volume, 111,250 cubic feet; length, approximately six diameters. This relation, together with the cigar shape, is in accordance with the plans of Colonel Renard’s dirigible, built and operated in France in 1884; the same general shape and proportions being found in the Ville de Paris. The first Lebaudy was pointed at the rear, which is generally admitted to be the proper shape for the least resistance, but to main- tain stability it was found necessary to put a horizontal and vertical plane there, so that it had to be made an ellipsoid of revolution to give attachment for these planes. The ballonet for air had a capacity of 22,958 cubic feet, or about one-fifth of the total volume. This is calculated to permit reaching a height of about 1 mile and to be able to return to the earth, keep- ing the gas bag always rigid. To descend from a height of 1 mile gas would be released by the valve, then air pumped into the ballonet to keep the gas bag rigid, these two operations being carried on alter- «AINLVd,, STGIDINIG HONSY4 “| 3LV1d yainbS>—'gQ6| ‘Hoday ueiuosyziWws ‘YVO JO SIIVLEG «!aluLvd,, aTgIDIYIG HONaY4 oullivale ainbgS—'gQ6| ‘HWodey uriuosyyiws MILITARY AERONAUTICS—SQUITER. 119 nately. On reaching the ground from the height of 1 mile the air would be at the middle of the lower part of the gas bag and would not entirely fill the ballonet. To prevent the air from rolling from one end to the other when the airship pitches, thus producing insta- bility, the ballonet was divided into three compartments by imper- meable cloth partitions. Numerous small holes were pierced in these partitions through which the air finally reached the two end com- partments. In September, 1907, the Patrie was enlarged by 17,660 cubic feet by the addition of a cylindrical section at the maximum diameter, in- creasing the length but not the maximum diameter. The gas bag is cut in panels; the material is a rubber cloth made by the Continental Tire Company at Hanover, Germany. It consists of four layers, arranged as follows: Weight, ounces, per square yard. Outer layer of cotton cloth covered with lead chromate______ 2.5 ayersOr vulcanized) rubber sss a sts Seles Si a Pere 2.5 Mayveruols COLLOMEClOGNE Soa =ee ere a pre eee ee es 2.5 Innerplayersotavuleani zed) mubberess = so 2 es ee 2 Aislenewetatife) otc 's hike aks epic) ide Lh tai gt 9.71 A strip of this cloth 1 foot wide tears at a tension of about 934 pounds. A pressure of about one inch of water can be maintained in the gas bag without danger. The lead chromate on the outside is to prevent the entrance of the actinic rays of the sun, which would cause the rubber to deteriorate. The heavy layer of rubber is to prevent the leaking of the gas. The inner layer of rubber is merely to prevent deterioration of the cloth by impurities in the gas. This material has the warp of the two layers of cotton cloth running in the same direc- tion and is called straight thread. The material in the ballonet weighs only about 7} ounces per square yard, and has a strength of about 336 pounds per running foot. When the Patrie was enlarged, in September, 1907, the specifications for the material allowed a maxi- mum weight of 10 ounces per square yard, a minimum strength of 907 pounds per running foot, and a loss of 5.1 cubic inches of hydro- gen per square yard in twenty-four hours at a pressure of 1.18 inches of water. Bands of cloth are pasted over the seams inside and out with a solution of rubber to prevent leaking through the stitches. Suspension.—One of the characteristics of the Patrie is the “ short ” suspension. The weight of the car is distributed over only about 70 feet of the length of the gas bag. To do this, an elliptical shaped frame of nickel steel tubes is attached to the bottom of the gas bag; steel cables run from this down to the car. A small hemp net is attached to the gas bag by means of short wooden cross pieces or toggles, which are let into holes in a strong canvas band which is 88292—sM 1908——9 120 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. sewed directly on the gas bag. The metal frame, or platform, is attached to this net by means of toggles, so that it can be quickly removed in dismounting the airship for transportation. The frame can also be taken apart. Twenty-eight steel cables about 0.2 inch in diameter run from the frame down to the car, and are arranged in triangles. Due to the impossibility of deforming a triangle, rigidity is maintained between the car and gas bag. The objection to the “short ” suspension of the Patrie is the defor- mation of the gas bag. A distinct curve can be seen in the middle. Car—tThe car is made of nickel steel tubes (12 per cent nickel). This metal gives the greatest strength for minimum weight. The car is boat-shaped, about 16 feet long, about 5 feet wide, and 24 feet high. About 11 feet separate the car from the gas bag. To prevent any chance of the fire from the engine communicating with the hydro- gen, the steel framework under the gas bag is covered with a non- combustible material. The pilot stands at the front of the car, the engine is in the middle, the engineer at the rear. Provision is made for mounting a telepho- tographic apparatus, and for a 100-candlepower acetylene searchlight. A strong pyramidal structure of steel is built under the car, pointing downward. In landing, the point comes to the ground first and this protects the car, and especially the propellers, from being damaged. The car is covered to reduce air resistance. It is so low, however, that part of the equipment and most of the bodies of those inside are exposed, so that the total resistance of the car is large. Motor—tThe first Lebaudy had a 40 horsepower Daimler-Mercedes benzine motor. The Patrie was driven by a 60 to 70 horsepower, 4-cylinder Panhard and Levassor benzine motor, making 1,000 revo- lutions per minute. Propellers.—There are two steel propellers 8} feet in diameter (two blades each) placed at each side of the engine, thus giving the shortest and most economical transmission. To avoid any tendency to twist the car, the propellers turn in opposite directions. They are “high speed,” making 1,000 to 1,200 revolutions per minute. The gasoline tank is placed under the car inside. the pyramidal frame. The gasoline is forced up to the motor by air compression. The exhaust is under the rear of the car, pointing down, and is covered with a metal gauze to prevent flames coming out. The fan which drives the air into the ballonet is run by the motor, but a dynamo is also provided so that the fan can always be kept running even if the motor stops. This is very essential, as the pressure must be main- tained inside the gas bag so that the latter will remain rigid and keep its form. There are five valves in all, part automatic and part both automatic and also controlled from the car with cords. The valves in the ballonet open automatically at less pressure than the gas valves, MILITARY AERONAUTICS—SQUIER. 121 so that when the gas expands all the air is driven out of the ballonet before there is any loss of gas. The ballonet valves open at a pres- sure of about 0.78 inch of water, the gas valves at about 2 inches. Stability.—Vertical stability is maintained by means of fixed horizontal planes. One having a surface of 150 square feet is attached at the rear of the gas bag, and due to its distance from the center of gravity is very efficient. The elliptical frame attached under the gas bag has an area of 1,055 square feet, but due to its proximity to the center of gravity has little effect on the stability. Just behind the elliptical frame is an arrangement sinfilar to the feathering on an arrow. It consists of a horizontal plane of 150 square feet and a vertical plane of 113 square feet. To maintain horizontal stability, that is, to enable the airship to move forward in a straight line with- out veering to the sides, fixed vertical planes are used. One runs from the center to the rear of the elliptical frame and has an area of 108 square feet. In addition to the vertical surface of 113 square feet at the rear of the elliptical frame, there is a fixed plane of 150 square feet at the rear of the gas bag. To fasten the two perpendicular planes at the rear of the gas bag, cloth flaps are sewed directly on the gas bag. Nickel-steel tubes are placed in the flaps which are then laced over the tubes. With these tubes as a base a hght tube and wire frame- work is attached and waterproof cloth laced on this framework. Additional braces run from one surface to the other and from each surface to the gas bag. The rudder is at the rear under the gas bag. It has about 150 square feet and is balanced. A movable horizontal plane near the center of gravity, above the car, is used to produce rising or descending motion, or to prevent an involuntary rising or falling of the airship due to expansion or con- traction of the gas or to other causes. After the adoption of this movable horizontal plane the loss of gas and ballast was reduced to a minimum. Ballast is carried in 10 and 20 pound sand bags. —'gQ6| ‘Vodey ueiuosyyiWS Smithsonian Report, 1908.—Squier. PLATE 4. Fic. 1.—FRENCH DIRIGIBLE “LA VILLE DE Paris.” Fic. 2.—GERMAN DIRIGIBLE “ZEPPELIN,’? WITH FLOATING HANGAR. MILITARY AERONAUTICS—SQUIER. 123 the material of which the gas bag is made without materially in- creasing the weight. The rudder has been altered somewhat in form. It was first pivoted on its front edge, but later on a vertical axis, somewhat to the rear of this edge. With the increase in size has come an increase in carrying capacity, and consequently a greater speed and more widely extended field of action. VILLE DE PARIS. This airship was constructed for Mr. Deutsch de la Meurthe, of Paris, who has done a great deal to encourage aeria! navigation. The first Ville de Paris was built in 1902, on plans drawn by Tatin, a French aeronautical engineer. It was not a success. Its successor was built in 1906, on plans of Surcouf, an aeronautical engineer and balloon builder. The gas bag was built at his works in Billan- court, the mechanical part at the Voisin shop, also in Billancourt. The plans are based on those of Colonel Renard’s airship, the France, built in 1884, and the Ville de Paris resembles the older airship in many particulars. In September, 1907, Mr. Deutsch offered the use of his airship to the French Government. The offer was accepted, but delivery was not to be made except in case of war or emergency. When the Patrie was lost in November, 1907, the military authorities immediately took over the Deutsch airship. Gas bag—The gas bag is 200 feet long for a maximum diameter of 344 feet, giving a length of about 6 diameters, as in the France and the Patrie; volume, 112,847 cubic feet; maximum diameter at about three-eighths of the distance from the front, approximately, as in the Patrie. The middle section is cylindrical, with conical sections in front and rear. At the extreme rear is a cylindrical sec- tion with eight smaller cylinders attached to it. The ballonet has a volume of 21,192 cubic feet, or about one-fifth of the whole volume, the same proportion found in the Patrie. The ballonet is divided into three compartments from front to rear. The division walls are of permeable cloth, and are not fastened to the bottom, so that ~when the middle compartment fills with air and the ballonet rises the division walls are lifted up from the bottom of the gas bag and there is free communication between the three compartments. The gas bag is made up of a series of strips perpendicular to a meridian line. These strips run around the bag, their ends meeting on the under meridian. This is known as the “ brachistode ” method of cutting out the material, and has the advantage of bringing the seams parallel to the line of greatest tension. They are, therefore, more likely to remain tight and not allow the escape of gas. The disadvantage lies in the fact that there is a loss of 334 per cent of material in cutting. The material was furnished by the Continental Tire Company, and has approximately the same tensile strength and 124 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. weight as that used in the Patrie. It differs from the other in one important feature—it 1s diagonal-thread; that is, the warp of the outer layer of cotton cloth makes an angle of 45° with the warp of the inner layer of cotton cloth. The result is to localize a rip or tear iy the material. A tear in the straight-thread material will continue along the warp, or the weave, until it reaches a seam. Valves.—There are five in all, made of steel, about 14 inches in diameter—one on the top connected to the car by a cord operated by hand only; two near the rear underneath. These are automatic but can be operated by hand from the car. Two ballonet valves directly under the middle are automatic and are also operated from the car by hand. The ballonet valves open automatically at a pres- sure of two-thirds of an inch of water; the gas valves open at a higher pressure. Suspension.—This airship has the “long” suspension; that is, the weight is distributed along practically the entire length of the gas bag. A doubled band of heavy canvas is sewn with six rows of stitches along the side of the gas bag. Hemp ropes running into steel cables transmit most of the weight of the car to these two canvas bands and thus to the gas bag. On both sides and below these first bands are two more. Lines run from these to points half way be- tween the gas bag and the car, then radiate from these points to dif- ferent points of attachment on the car. This gives the triangular or nondeformable system of suspension, which is necessary in order to have the car and gas bag rigidly attached to each other. With this “long ” suspension, the Ville de Paris does not have the deformation so noticeable in the gas bag of the Patrie. Car.—This is in the form of a trestle. It is built of wood, with aluminum joints and 0.12-inch wire tension members. It is 115 feet long, nearly 7 feet high at the middle, and a little over 53 feet wide at the middle. It weighs 660 pounds and is considered un- necessarily large and heavy. The engine and engineer are well to the front; the aeronaut with steering wheels is about at the center ¥) of gravity. Motor.—The motor is a 70 to 75 horsepower “ Argus,” and is excep- tionally heavy. | . Propeller—The propeller is placed at the front end of the car. It thus has the advantage of working in undisturbed air; the disad- vantage is the long transmission and difficulty in attaching the pro- peller rigidly. It has two blades and is 19.68 feet long with a pitch of 26.24 feet. The blades are of cedar with a steel arm. The pro- peller makes a maximum of 250 turns per minute when the engine is making 900 revolutions. Its great diameter and width compensate for its small speed. MILITARY AERONAUTICS—SQUIER. 125 Stability —This is maintained entirely by the cylinders at the rear. Counting the larger one to which the smaller ones are attached, there are five, arranged side by side corresponding to the horizontal planes of the Patrie, and five vertical ones corresponding to the Patrie’s vertical planes. The volume of the small cylinders is so calculated that the gas in them is just sufficient to lift their weight, so they neither increase or decrease the ascensional force of the whole. The horizontal projection of these cylinders is 1,076 square feet. The center of this projection is 72 feet from the center of gravity of the gas. The great objection to this method of obtaining stability is the air resistance due to these cylinders, and consequent loss of speed. The stability of the Ville de Paris in a vertical plane is said to be superior to that of the Patrie, due to the fact that the stability planes of the latter do not always remain rigid. The independent velocity of the Ville de Paris probably never exceeded 25 miles an hour. Rudder.—The rudder has a double surface of 150 square feet placed at the rear end of the car, 72 feet from the center of gravity. It is not balanced, but is inclined slightly to the rear so that its weight would make it point directly to the rear if the steering gear should break. Two pairs of movable horizontal planes, one at the rear of the car having 43 square feet, and one at the center of gravity (as on the Patrie) having 86 square feet, serve to drive the airship up or down without losing gas or ballast. Guide ropes.—A 400-foot guide rope is attached at the front end of the car. A 230-foot guide rope is attached to the car at the center of gravity. About thirty men are required to maneuver the Ville de Paris on the ground. The pilot has three steering wheels, one for the rudder and two for the movable horizontal planes. The instruments used are an aneroid barometer, a registering barometer giving heights up to 1,600 feet, and an ordinary dynamometer which can be connected either with the gas bag or ballonet by turning a valve. A double column of water is also connected to the tube to act as a check on the dynamometer. Due to the vibration: of the car caused by the motor, these instruments are suspended -by rubber attachments. Even with this arrangement it is necessary to steady the aneroid barometer with the hand in order to read it. The vibration prevents the use of the statoscope. England. Miuitary Drricistre No. 1. The gas bag of this airship was built about five years ago by Colonel Templar, formerly in command of the aeronautical establish- ment at Aldershot. His successor, Colonel Capper, built the me- 126 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. chanical part during the spring and summer of 1907, with the assist- ance of Mr. S. F. Cody, a mechanical engineer. It was operated by Colonel Capper as pilot, with Mr. Cody in charge of the engine. Several ascents were made at Aldershot. In October, 1907, they made a trip from Aldershot to London, a distance of about 40 miles, landing at the Crystal Palace. For several days the rain and wind prevented attempting the return journey. On October 10 a strong wind threatened to carry away the airship, so the gas bag was cut open by the sergeant in charge. Gas bag.—This is made of eight layers of gold beater’s skin. It is cylindrical in shape with spherical ends. Volume, 84,768 cubic feet; length, 1114 feet; maximum diameter, 314 feet.” The elonga- tion therefore is only about 32. There is no ballonet, but due to the toughness of the gold beater’s skin a much higher pressure can safely be maintained than in gas bags of rubber cloth. Without a ballonet, however, it would not be safe to rise to the heights reached by the Patrie. Valves—The valves are made of aluminum and are about 12 inches in diameter. Suspension.—In this airship they have succeeded in obtaining a “long” suspension with a short boat-shaped car, a combination very much to be desired, as it distributes the weight over the entire length of the gas bag and gives the best form of car for purposes of obser- vation and for maneuvering on the ground. To obtain this combi- nation they have had to construct a very heavy steel framework, which cuts down materially the carrying capacity, and, moreover, this framework adds greatly to the air resistance. This is the only airship in Europe having a network to support the car. In addi- tion, four silk bands are passed over the gas bag and wires run from their extremities down to the steel frame. This steel frame is in two tiers—the upper is rectangular in cross section and supports the rudder and planes, the lower part is triangular in cross section and supports the car. The joints are aluminum. Car.—This is of steel and is about 30 feet long. To reduce air resistance the car is covered with cloth. Motor.—aA 40 to 50 horsepower 8-cylinder Antoinette motor is used. It is set up on top of the car. The benzine tanks are supported above in the framework. Gravity feed is used. Propellers ——There are two propellers, one on each side, with two blades each, as in the Patrie. They are made of aluminum, 10 feet in diameter, and make 700 revolutions per minute. The transmission is by belt. Stability —This is maintained by means of planes. At the extreme rear is a large fixed horizontal plane. In front of this is a pair of hinged horizontal planes. Under this is the hexagonal-shaped rud- *L ON aqgI9INIG HSIIDNA °G 3LVI1d ‘deinbs>—g06| ‘Hoday ux;uosy})UIS ‘UVO SO STIVLAG «: NITadd3Z,, SISISIYIG NVWYaS "9 3ALV1d syainbg>—gQ6| 'Hodey urluosyziws MILITARY AERONAUTICS—SQUIER. 17 der. It is balanced. Two pairs of movable horizontal planes, 8 feet by 4 feet, each placed at the front, serve to guide the airship up and down, as in the Patrie and Ville de Paris. These planes have addi- tional inclined surfaces, which are intended to increase the stability in a vertical plane. All these planes, both fixed and movable, are constructed like kites, of silk stretched on bamboo frames. The guide rope is 150 feet long. Speed attained, about 16 miles per hour. This airship with a few improvements added has been in operation the past few months. The steel framework connecting the gas bag to the car is now entirely covered with canvas, which must reduce the resistance of the air very materially. The canvas covering, inclosing the entire bag, serves as a reinforcement to the latter and at the same time gives attachment to the suspension underneath. It is re- ported that a speed of 20 miles an hour has been attained with the reconstructed airship. A pyramidal construction similar to that on the Patrie has been built under the center of the car to protect the car and propellers on landing. A single movable horizontal plane placed at the front end of the car and operated by the pilot, controls the vertical motion. Germany. Three different types of airships are being developed in Germany. The Gross is the design of Major Von Gross, who commands the balloon battalion at Tegel, near Berlin. The Parseval is being de- veloped by Major Von Parseval, a retired German officer, and the Zeppelin is the design of Count Zeppelin, also a retired officer of the German army. THE GROSS. The first airship of this type made its first ascension on July 23, 1907. The mechanical part was built at Siemen’s Electrical Works in Berlin; the gas bag by the Riedinger firm in Augsburg. Gas bag.—The gas bag is made of rubber cloth furnished by the Continental Tire Company, similar to that used in the Ville de Paris. Tt is diagonal thread, but there is no inner layer of rubber, as they do not fear damage from impurities in the hydrogen gas. Length, 1314 feet; maximum diameter, about 394 feet; volume, 63,576 cubic feet. The elongation is about 34. The form is cylindrical with spherical cones at the ends, the whole being symmetrical. Suspension.—The suspension is practically the same as that of the Patrie. A steel and aluminum frame is attached to the lower part of the gas bag, and the car is suspended on this by steel cables. The ob- jection to this system is even more apparent in the Gross than in the Patrie. A marked dip along the upper meridian of the gas bag shows plainly the deformation. 128 ANNUAL REPORF_ SMITHSONIAN INSTITUTION, 1908. Car—tThe car 1s boat shaped, like that of the Patrie. It is sus- pended 13 feet below the gas bag. Motor.—The motor is a 20 to 24 horsepower, four-cylinder Daimler- Mercedes. Propellers.—There are two propellers 8.2 feet in diameter, each hay- ing two biades. They are placed one on each side, but well up under the gas bag near the center of resistance. The transmission is by belt. The propellers make 800 revolutions per minute. Stability.—The same system, with planes, is used in the Von Gross as in the Patrie, but it is not nearly so well developed. At the rear of the rigid frame attached to the gas bag are two fixed horizontal planes, one on each side. A fixed vertical plane runs down from be- tween these horizontal planes, and is terminated at the rear by the rudder. —go6| ‘Hodey ueiuosy}iws ‘YvOd dO SIIVLAG SNIMOHS Sf) “ON STaIDSIYIG SdYOOD TVNDIS$ er ES 3A SIT Se Migs TS EEF Lge ae ea ss » = Pee: 7 ae | i i j | i 4 SOL SEE Vale ainbg>—'g96| ‘HOday uRluosyyiWS Smithsonian Report, 1908.—Squier. PLATE 11 SIGNAL Corps DirRiciBLE No. 1, SHOWING DETAILS OF ENGINE. ‘USAN ‘VHVWO LYOY ‘LSOd SdYOD TVNDIS ‘LNVId DNILVYSNS5 NA90YH0AH ONV ‘YS1LSWOSV5 ‘ASNOH NOOTIVg 1331S | 4 is is “OL ALV1d aInbS—-gQ6| ‘Hodey ueiuosyyiWS MILITARY AERONAUTICS——SQUIER. 133 The total lifting power of this airship is 1,350 pounds, of which 500 pounds are available for passengers, ballast, fuel, ete. At its official trials a speed of 19.61 miles per hour was attained over a measured course, and an endurance run lasting two hours, during which 70 per cent of the maximum speed was maintained. Dirigible No. 1, as this airship has been named, has already served a very important purpose in initiating officers of the Signal Corps in the construction and operation of a dirigible balloon. With the experience now acquired the United States Government is in a posi- tion to proceed with the construction and operation of an airship worthy of comparison with any now in existence, but any efforts in this direction must await the action of Congress in providing the necessary funds. * * * IT. Avrarion. This division comprises all those forms of heavier-than-air flying machines which depend for their support upon the dynamic reaction of the atmosphere. There are several subdivisions of this class de- pendent upon the particular principle of operation. Among these may be mentioned the aeroplane, orthopter, helicopter, etc. The only one of these that has been sufficiently developed at present to carry a man in practical flight is the aeroplane. There have been a large number of types of aeroplanes tested with more or less success, and of these the following are selected for illustration. REPRESENTATIVE AEROPLANES OF VARIOUS TYPES. THE WRIGHT BROTHERS’ AEROPLANE. The general conditions under which the Wright machine was built for the Government were that it should develop a speed of at least 36 miles per hour and in its trial flights remain continuously in the air for at least one hour. It was designed to carry two persons hav- ing a combined weight of 350 pounds, and also sufficient fuel for a flight of 125 miles. The trials at Fort Myer, Virginia, in September of 1908, indicated that the machine was able to fulfill the require- ments of the government specifications. The aeroplane has two superposed main surfaces 6 feet apart, with a spread of 40 feet and a distance of 64 feet from front to rear. The area of this double supporting surface is about 500 square feet. The surfaces are so constructed that their extremities may be warped at the will of the operator. A horizontal rudder of two superposed plane surfaces about 15 feet long and 3 feet wide is placed in front of the main surfaces. Behind the main planes is a vertical rudder formed of two surfaces 134 ANNUAL REPORE SMITHSONIAN INSTITUTION, 1908. trussed together, about 54 feet long and 1 foot wide. The auxiliary surfaces and the mechanism controlling the warping of the main sur- faces are operated by three levers. The motor, which was designed by the Wright brothers, has four cylinders and is water cooled. It develops about 25 horsepower at 1,400 revolutions per minute. There are two wooden propellers, 83 feet in diameter, which are designed to run at about 400 revolutions per minute. The machine is supported on two runners, and weighs about 800 pounds. A monorail is used in starting. The Wright machine has attained an estimated maximum speed of about 40 miles per hour. On September 12, a few days before the accident which wrecked the machine, a record flight of one hour fourteen minutes twenty seconds was made at Fort Myer, Virginia. Since that date Wilbur Wright, at Le Mans, France, has made better records, on one occasion remaining in the air for more than an hour and a half with a passenger. A reference to the attached illustrations of this machine will show its details, its method of starting, and its appearance in flight. THr HERRING AEROPLANE. The Signal Corps of the Army has contracted with A. M. Herring, of New York, to furnish an aeroplane under the conditions enumer- ated in the specification already referred to. Mr. Herring made technical delivery of his machine at the aeronautical testing ground at Fort Myer, Virginia, on October 13, 1908. In compliance with the request of Mr. Herring the details of this ‘machine will not be made public at present, but the official tests re- - quired under the-contract will be conducted in public, as has been the case with other aeronautical devices. Opportunity will be af- forded any one to observe the machine in operation. This machine embodies new features for automatic control and contains an engine of remarkable lightness per horsepower. THE FARMAN AEROPLANE. The Farman flying machine has two superposed aerosurfaces 4 feet 11 inches apart, with a spread of 42 feet 9 inches and 6 feet 7 inches from front to rear. The total sustaining surface is about 560 square feet. : A box tail 6 feet 7 inches wide and 9 feet 10 inches long in rear of the main surfaces is used to balance the machine. The vertical sides of the tail are pivoted along the front edges, and serve as a vertical rudder for steering in a horizontal plane. There are two parallel, vertical partitions near the middle of the main supporting surfaces, and one vertical partition in the middle of the box tail. A horizontal rudder in front of the machine is used to elevate or depress it in flight. “NOILONYLSNOD JO SIIVLAG *3NV1IdOH3Y «SYHSHLOYG LHOINAA yl ae eval ct “aiInbDGS—'"gQ6| ‘Hoday ueiuosy}yIWS "NOILONYLSNOD JO STIVLAG *S3NV1IdOYSY SYSHLOYG LHDIYM ‘pl aALV1d ‘ainbs>—'gQ6| ‘Wodey uRlUosYyIWS ‘M3IA YVAY ‘NOILONYLSNOD JO STivLag ‘SNV1d0usy ‘SHAHLOYG LHSIYAA "GL aLVid ‘yainbS—'go6| ‘Hodey uejuosy}iWS "S061 ‘6 HSEWALdaS “VA ‘USAIN, LYO4 ‘ANVIdOUSY SHSHLOUG LHOINAA ‘9, 3ALV1d sainbs—'gg6| ‘Hoday uejuosy}IWS MILITARY AERONAUTICS—SQUIER. 135 The motor is an eight-cylinder Antoinette of 50 horsepower weighing 176 pounds, and developing about 38 horsepower at 1,050 revolutions per minute. The propeller is a built-up steel frame covered with aluminum sheeting, 7} feet in diameter, with a pitch of 4 feet 7 inches. It is mounted directly on the motor shaft immediately in rear of the mid- dle of the main surfaces. The framework is of wood, covered with canvas. A chassis of steel ‘tubing carries two pneumatic-tired bicycle wheels. Two smaller wheels are placed under the tail. The total weight of the machine is 1,166 pounds. The main surfaces support a little over 2 pounds per square foot. The machine has shown a speed of about 28 miles per hour and no starting apparatus is used. On January 13, 1908, Farman won the Grand Prix of the Aero Club of France in a flight of one minute and twenty-eight seconds, in which he covered more than a kilometer. It is reported that on October 30, 1908, a flight of 20 miles, from Mourmelon to Rheims, was made with this machine, THE BLERIOT AEROPLANE. Following Farman’s first flight from town to town, M. Blériot with his monoplane aeroplane made a flight from Toury to the neigh- borhood of Artenay and back, a total distance of about 28 kilometers. He landed twice during these flights and covered 14 kilometers of his journey in about ten minutes, or attained a speed of 52 miles an hour. THE JUNE Bue. The June Bug was designed by the Aerial Experiment Association, of which Alexander Graham Bell is president. It has two main superposed aerosurfaces with a spread of 42 feet and 6 inches, includ- ing wing tips, with a total supporting surface of 370 square feet. The tail is of the box type. The vertical rudder above the rear edge of the tail is 30 inches square. The horizontal rudder in front of the main surfaces is 30 inches wide by 8 feet long. There are four triangular wing tips pivoted along their front edges for maintaining transverse equilibrium. The vertical rudder is operated by a steering wheel, and the movable tips by cords attached to the body of the aviator. The motor is a 25-horsepower, 8-cylinder, air-cooled Curtiss. The single wooden propeller immediately behind the main surfaces is 6 feet 2 inches in diameter and mounted directly on the motor shaft. It has a pitch angle of about 17° and is designed to run at about 1,200 revolutions per minute. 88292—sm 1908——10 136 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. The total weight of the machine, with aviator, is 650 pounds. It has a load of about 12 pounds per square foot of supporting sur- face. Two pneumatic-tired bicycle wheels are attached to the lower part of the frame. With this machine, Mr. G. H. Curtiss, on July 4, 1908, won the Scientific American trophy by covering the distance of over a mile in one minute and forty-two and two-fifths seconds at a speed of about 39 miles per hour. SOME GENERAL CONSIDERATIONS WHICH GOVERN THE DESIGN OF AN AEROPLANE. The design of an aeroplane may be considered under the heads of support, resistance and propulsion, stability, and control. Support. In this class of flying machines, since the buoyancy is practically insignificant, support must be obtained from the dynamic reaction of the atmosphere itself. In its simplest form, an aeroplane may be considered as a single plane surface moving through the air. The law of pressure on such a surface has been determined and may be expressed as follows: P = %cAV? sina (1) in which P is the normal pressure upon the plane, % is a constant of figure, o the density of the air, A is the area of the plane, V the relative velocity of translation of the plane through the air, and a the angle of flight. This is the form taken by Duchemin’s formula for small angles of flight such as are usually employed in practice. The equation shows that the upward pressure on the plane varies directly with the area of the plane, with the sine of the angle of flight, with the density of the air, and also with the square of the velocity of translation. It is evident that the total upward pressure developed must be at least equal to the weight of the plane and its load, in order to support the system. If P is greater than the weight, the machine will ascend ; if less, it will descend. The constant 4: depends only upon the shape and aspect of the plane, and should be determined by experiment. For example, with a plane 1 foot square Ao = 0.00167, as determined by Langley, when P is expressed in pounds per square foot, and V in feet per second. Equation (1) may be written P OV ee Q2ko sin «a If P and a are kept constant then the equation has the form AV? = constant. (2) "8061 “6 YSaW31dag “VA ‘YSAW LYOJ ‘SNV1dONSY SYSHLONG LHOIUM Smell el bS—'g061 ‘Podey ueiuosy}iWS Smithsonian Report, 1908.—Squier. — PLATE 18 WRIGHT BROTHERS’ AEROPLANE, FORT MYER, VA., SEPTEMBER 12, 1908. Smithsonian Report, 1908.—Squier. PLATE 19. WRIGHT BROTHERS’ AEROPLANE, ForT MYER, VA., SEPTEMBER 12, 1908. Time of flight, 1 hour 14 minutes 20 seconds. PLATE 20. Smithsonian Report, 1908.—Squier. ~_ | H | | i WRIGHT BROTHERS’ AEROPLANE, FORT MYER, VA., SEPTEMBER 12, 1908. Time of flight, 1 hour 14 minutes 20 seconds. MILITARY AEKRONAUTICS—SQUIER. 137 PRINCIPLE OF REEFING IN AVIATION. An interpretation of (2) reveals interesting relations. The sup- porting area varies inversely as the square of the velocity. For example, in the Wright aeroplane, the supporting area at 40 miles per hour is 500 square feet, while if the speed is increased to 60 miles = ‘ 000 per hour this area need be only 150: = 222 square feet, or less than one-half of its present size. At 80 miles per hour the area would be reduced to 125 square feet, and at 100 miles per hour only 80 square feet of supporting area is required. These relations are conveniently exhibited graphically. It thus appears that if the angle of flight be kept constant in the Wright aeroplane, while the speed is increased to 100 miles per hour. we may picture a machine which has a total supporting area of 80 square feet, or a double surface, each measuring about 24 by 16 feet or 4 by 10 feet if preferred. Furthermore, the discarded mass of the 420 square feet of the original supporting surface may be added to the weight of the motor and propellers in the design of a reduced aero- plane, since in this discussion the total mass is assumed constant at 1,000 pounds. In the case of a bird’s flight, its wing surface is “ reefed ” as its velocity is increased, which instinctive action serves to reduce its head resistance and skin-frictional area, and the consequent power required for a particular speed. Determination of k for arched surfaces.—Since arched surfaces are now commonly used in aeroplane construction, and as the above equation (1) applies to plane surfaces only, it is important to deter- mine experimentally the value of the coefficient of figure /, for each type of arched surface employed, especially as % is shown in some cases to vary with the angle of flight a; 1. e., the inclination of the chord of the surface to the line of translation. Assuming a constant, however, we may compare the lift of any particular arched surface with a plane surface of the same projected plan and angle of flight. To illustrate, in the case of the Wright aeroplane, let us assume P = 1,000 pounds = total weight = W. A = 500 square feet. V = 40 miles per hour = 60 feet per second. a = 7°, approximately. 1% 1,000 Whence ke — : DAV? sina 2X 500 x 60? x4 = 0.0022 (V = foot-seconds) = 0.005 (V = miles per hour). 138 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Comparing this value of ko with Langley’s value 0.004 for a plane surface V being in miles per hour, we see that the lift for the arched surface is 25 per cent greater than for a plane surface of the same projected plan. That is to say, this arched surface is dynamically equivalent to a plane surface of 25 per cent greater area than the projected plan. Such a plane surface may be defined as the “ equiva- lent plane.” Resistance and propulsion. The resistance of the air to the motion of an aeroplane is composed of two parts, (a) the resistance due to the framing and load; (0) the necessary resistance of the sustaining surfaces; that is, the drift or horizontal component of. pressure, and the unavoidable skin friction. Disregarding the frame and considering the aeroplane as a simple plane surface, we may express the resistance by the equation R = W tana + 2fA (3) in which R is the total resistance, W the gross weight sustained, a the angle of flight, 7 the friction per square unit of area of the plane, A the area of the plane. The first term of the second member gives the drift, the second term the skin friction. The power required to propel the aeroplane is Jel == Jy in which H is the power, V the velocity. Now W varies as the second power of the velocity, as shown by equation (1), and 7 varies as the power 1.85, as will be shown later. Hence we conclude that the total resistance R of the air to the aeroplane varies approximately as the square of its speed, and the propulsive power practically as the cube of speed. Most advantageous speed and angle of flight—Again, regarding W and A as constant, we may, by equation (1), compute a for various values of V, and find f for those velocities from the skin-friction table to be given presently. Thus a, R, and H may be found for various velocities of flight, and their magnitudes compared. In this way the values in Table 1 were computed for a soaring plane 1 foot square, ‘weighing 1 pound, assuming iio = 0.004, which is approximately Langley’s value when V is in miles per hour. ‘Iasuossud puw JYSIUAA O[[LAIQ “JARs oY] JOY Apvory "S061 ‘SL YSANALdaS “VA ‘YSAI) LYOS ‘ANV1IdOYHSY «SHSHLOYUG LHDINMA “lo dlv1d ainbsS—'gQ6| ‘Hoday uRrluosy}IWS Smithsonian Report, 1908.—Squier. PLATE 22. WRIGHT BROTHERS’ AEROPLANE, FORT MYER, VA., SEPTEMBER 12, 1908. Oryille Wright and passenger. Time, 9 minutes 6 seconds. Smithsonian Report, 1908.—Squier. PLATE 23. Fic. 1.—FARMAN AEROPLANE. Fia. 2.—‘ JUNE BUG” AEROPLANE, HAMMONDSPORT, N. Y. Aerial Experiment Association. MILITARY AERONAUTICS—SQUIER. 139 TABLE 1.—Computed power required to tow a plane 1 foot square weighing 1 pound horizontally through the air at various speeds and angles of flight. istance. i r , : Angle eh am ee Tow-line eee Velocity (miles per honr). of : power. hone flight Driit. Friction. Total. power. cS Pounds. Pounds. Pounds. | Ft. lb. sec. | Pounds. Beer eee Sons Saree a ee aise 8.25 0.145 0.0170 0.162 718) wueu SOP e eae foe mnie a rian ys siniee Pei ais 5.94 . 104 . 0226 . 1266 6.51 84,3 40 es eA ea ee ae Seeks hi 4,52 . 790 . 0289 . 1079 6.32 86.7 HN eee RB CLC ESE Se OE EEE 3.55 . 0621 . 0360 . 0981 6.39 86.1 BO eee en ea emaia eee micas 2.88 . 0500 . 0489 . 0939 6.89 80.2 GO seer re erin Soe sie ocala 2.03 . 0354 . 0614 . 0962 8.50 64.7 (os dost £2452 aE aA eee ore 1.47 . 0257 . 0814 - 1071 11.00 50.0 Sess eee ase eee oe se 1,12 - 0195 . 1045 . 1240 14. 56 35.8 SO eee oe aia aoe ss -88 . 0154 . 1800 . 1454 19.17 28.7 ROW R- 33S See ee ee eae ay . 0124 . 1584 . 1708 25. 00 22.0 Column two, giving values of a for various speeds, from equation (1). Thus, at 30 miles per hour, W St OPN Va 5 Oe 004K 1. 307 whence a = 8.25°. Ht is computed Column three is computed from the term W tan a in equation (3), thus: Drrtg —W tan a — 1>C tan: 3:25° = 0/145: Column four is computed from the term 2/A in equation (3), f being taken from the skin-friction table, to be given presently. The table shows that if a thin plane 1 foot square, weighing 1 pound, be towed through the air so as just to float horizontally at various velocities and angles of flight, the total resistance becomes a minimum at an angle of slightly less than 3°, and at a velocity of about 50 miles per hour; also that the skin-friction approximately equals the drift at this angle. The table also shows that the propulsive power for the given plane is a minimum at a speed of between 40 and 45 miles per hour, the angle of flight then being approximately 4.5°. The last column of the table shows that the maximum weight carried per horsepower is less than 90 pounds. This horse load may be increased by changing the foot-square plane to a rectangular plane and towing it long side foremost; also by lightening the load, and letting the plane glide at a lower speed; but best of all, perhaps, by arching it like a vulture’s wing and also towing it long side foremost as is the prevailing practice with aeroplanes. Stability and control. The question of stability is a serious one in aviation, especially as increased wind velocities are encountered. In machines of the aero- 140 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. plane type there must be some means provided to secure fore and aft stability and also lateral stability. A large number of plans have been proposed for the accomplish- ment of these ends, some based upon the skill of the aviator, others operated automatically, and still others employing a combination of both. At the present time no aeroplane has yet been publicly exhibited which is provided with automatic control. There is little difference of opinion as to the desirability of some form of automatic control. The Wright aeroplane does not attempt to accomplish this, but depends entirely upon the skill of the aviator to secure both lateral and longitudinal equilibrium; but it is understood that a device for this purpose is one of the next to be brought forward by them. Much* of the success of the Wright brothers has been due to their logical procedure in the development of the aeroplane, taking the essentials, step by step, rather than attempting everything at once, as is so often the practice with inexperienced inventors. The aviator’s task is much more difficult than that of the chauffeur. With the chauffeur, while it is true that it requires his constant atten- tion to guide his machine, yet he is traveling on a roadway where he can have due warning through sight of the turns and irregularities of the course. The fundamental difference between operating the aeroplane and the automobile is that the former is traveling along an aerial high- way which has manifold humps and ridges, eddies and gusts, and since the air is invisible he can not see these irregularities and inequali- ties of his path, and consequently can not provide for them until he has actually encountered them. He must feel the road since he can not see it. Some form of automatic control whereby the machine itself promptly corrects for the inequalities of its path is evidently very desirable. As stated above, a large number of plans for doing this have been proposed, many of them based on gyrostatic action, mov- able side planes, revolving surfaces, warped surfaces, etc. A solu- tion of this problem may be considered as one of the next important steps forward in the development of the aeroplane. III. Hypromecuanic RELATIONS. SOME GENERAL RELATIONS BETWEEN SHIPS IN AIR AND IN WATER. At the present moment so many minds are engaged upon the gen- eral problem of aerial navigation that any method by which a broad forecast of the subject can be made is particularly desirable. Each branch of the subject has its advocates, each believing implicitly in the superiority of his method. On the one hand the adherents of MILITARY AERONAUTICS—SQUIER. 141 the dirigible balloon have little confidence in the future of the aero- plane, while another class have no energy to devote to the dirigible balloon, and still others prefer te work on the pure helicopter princi- ple. As a matter of fact, each of these types is probably of perma- nent importance, and each particularly adapted to certain needs. Fortunately for the development of each type, the experiments made with one class are of value to the other classes, and these in turn bear close analogy to the types of boats used in marine navi- gation. The dynamical properties of water and air are very much alike, and the equations of motion are similar for the two fluids, so that the data obtained from experiments in water, which are very extensive, may with slight modification be appled to computations for aerial navigation. Helmholtz’s theorem.—V on Helmholtz, the master physicist of Ger- many, who illuminated everything he touched, has fortunately con- sidered this subject in a paper written in 1873. The title of his paper is “ On a theorem relative to movements that are geometrically similar in fluid bodies, together with an application to the problem of steering balloons.” In this paper Helmholtz affirms that, although the differential equations of hydromechanics may be an exact expression of the.laws controlling the motions of fluids, still it is only for relatively few and simple experimental cases that we can obtain integrals appropriate to the given conditions, particularly if the cases involve viscosity and surfaces of discontinuity. Hence, in dealing practically with the motion of fluids, we must depend upon experiment almost entirely, often being able to predict very little from theory, and that usually with uncertainty. Without integrating, however, he applies the hydrodynamic equations to transfer the observations made on any one fluid with given models and speeds over to a geometrically similar mass of another fluid involving other speeds and models of different magnitudes. By this means he is able to compute the size, velocity, resistance, power, etc., of aerial craft from given, or observed, values for marine craft. He also deduces laws that must inevitably place a limit upon the possible size and velocity of aerial craft without, however, indi- cating what that limit may be with artificial power. Applying this mode of reasoning to large birds he concludes by saying that “ It therefore appears probable that in the model of the great vulture nature has already reached the limit that can be attained with the muscles as working organs, and under the most favorable conditions of subsistence, for the magnitude of a creature that shall raise itself by its wings and remain a long time in the air.” In comparing the behavior of models in water and air he takes account of the density and viscosity of the media, as these were well 142 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. known at the date of his writing, 1873; but he could not take ac- count of the sliding, or skin-frictidn, because in his day neither the magnitude of such friction for air, nor the law of its variation with velocity, had been determined. Skin-friction in ar. Even as late as Langley’s experiments, skin-friction in air was regarded as a negligible quantity, but due to the work of Doctor Zahm, who was the first to make any really extensive and reliable experiments on skin-friction in air, we now can estimate the magni- tude of this quantity. As a result of his research he has given in his paper on “ Atmospheric friction” the following equation: Ff = 0.00000778 2°" o. . . (v=feet per second), f= 9.0000158 2~-°% y®. . . (v=miles per hour), in which / is the average skin-friction per square foot, and / the length of surface. From this equation the accompanying table of resistances was computed, and is inserted here for the convenience of engineers: TABLE 2,—Friction per square foot for various speeds and lengths of surface. Average friction, in pounds per square foot. Wind speed (miles per hour). 1-foot 2-foot 4-foot 8-foot 16-foot 32-foot plane. plane. plane. plane. plane. plane. Oe ee AS See ete te ee 0. 000303 0. 000289 0. 000275 0. 000262 0. 000250 0. 000288 LON a Sass ree lk saa ee . 00112 . 00105 . 00101 . 000967 . 000922 . 000878 DDD 5s Pe eee, Spores ie wae ee lae | . 00237 . 00226 . 00215 . 00205 . 00195 . 00186 20 se ot noe batecosnists ae Sees | . 00402 . 00384 . 00365 . 00349 . 00332 . 00317 DO epelos Sassen eee . 00606 . 00579 . 00551 «00527 - 00501 . 00478 SOR Ase ieieteeca i cise soe eceene . 00850 . 00810 . 00772 . 00736 - OO70L . 00668 BBY j5 oot fae of So ee . 01180 . 0108 . 0103 . 0098 . 00932 . 00888 AO ene etna Soe ae eee . 0145 . 0138 . 0132 . 0125 . 0125 . 0114 BOE Mee si) ane on ee | 0219 0209 0199 0190 0181 0172 GOB AR eit soscce oeesseeeern | . 0307 . 0293 . 0279 . 0265 . 0253 - 0242 1) Saco nee OceeCE toredeeesc . 0407 . 0390 . 0370 . 0358 . 0337 . 0321 SO ee: Sete a attes sueials cee . 0522 . 0500 . 0474 . 0452 . 0431 . 0411 UD cdnssead doseeeaaaseee ares . 0650 . 0621 . 0590 . 0563 . 0536 . 0511 HOO een enS.. Le echisleses koe . 0792 . 0755 .0719 . 0685 . 0652 . 0622 The numbers within the rules represent data coming within the range of observation. These observations show that “ the frictional resistance is at least as great for air as water, in proportion to their densities. In other words, it amounts to a decided obstacle in high- speed transportation. In aeronautics it is one of the chief elements MILITARY AERONAUTICS—SQUIER. 143 of resistance both to hull-shaped bodies and to aero-surfaces gliding at small angles of flight.” Relative dynamic and buoyant support.—Peter Cooper-Hewitt has given careful study to the relative behavior of ships in air and in water. He has made a special study of hydroplanes, and has pre- pared graphic representations of his results which furnish a valuable forecast of the problem of flight. Without knowing of Helmholtz’s theorem, Cooper-Hewitt has inde- pendently computed curves for ships and hydroplanes from actual data in water, and has employed these curves to solve analogous prob- lems in air, using the relative densities of the two media, approxi- mately 800 to 1, in order to determine the relative values of support by dynamic reaction and by displacement for various weights and speeds. An analysis of these curves leads to conclusions of importance, some of which are as follows: The power consumed in propelling a displacement vessel at any constant speed, supported by air or water, is considered as being two- thirds consumed by skin-resistance, or surface resistance, and one- third consumed by head resistance. Such a vessel will be about 10 diameters in length, or should be of such shape that the sum of the power consumed in surface friction and in head resistance will be a minimum (torpedo shape). The power required to overcome friction due to forward movement will be about one-eighth as much for a vessel in air as for a vessel of the same weight in water. Leaving other things out of consideration, higher speeds can be obtained in craft of small tonnage by the dynamic reaction type than by the displacement type, for large tonnages the advantages of the displacement of type are manifest. A dirigible balloon carrying the same weight, other things being equal, may be made to travel about twice as fast as a boat for the same power or be made to travel at the same speed with the expendi- ture of about one-eighth of the power. As there are practically always currents in the air reaching at times a velocity of many miles per hour, a dirigible balloon should be constructed with sufficient power to be able to travel at a speed of about 50 miles per hour, in order that it may be available under prac- tical conditions of weather. In other words, it should have sub- stantially as much power as would drive a boat, carrying the same weight, 25 miles an hour, or should have the same ratio of power to size as the Lusttania. M otors.—It is the general opinion that any one of several types of internal combustion motors at present available is suitable for use with dirigible balloons. With this type hghtness need not be ob- 144 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. tained at the sacrifice of efficiency. In the aeroplane, however, light- ness per output is a prime consideration, and certainty and reliability of action is demanded, since if by chance the motor stops the ma- chine must immediately glide to the earth. A technical discussion of motors would of itself require an extended paper, and may well form the subject of a special communication. Propellers —The fundamental principles of propellers are the same for air as for water. In both elements the thrust is directly proportional to the mass of fluid set in motion per second. A great variety of types of propellers have been devised, but thus far only the screw propeller has proved to be of practical value in air. The theory of the screw propeller in air is substantially the same as for the deeply submerged screw propeller in water, and therefore does not seem to call for treatment here. There is much need at present for accurate aerodynamic data on the behavior of screw propellers in air, and it is hoped that engineers will soon secure such data and present it in practical form for the use of those interested in airship design. Limitations —Euclid’s familiar “square-cube” theorem connect- ing the volumes and surfaces of similar figures, as is well known, operates in favor of increased size of dirigibles and limits the pos- sible size of heavier-than-air machines in single units and with concentrated loads. It appears, however, that both fundamental forms of aerial craft will likely be developed, and that the lighter-than-air type will be the burden-bearing machine of the future, whereas the heavier-than- air type will be limited to comparatively low tonnage, operating at relatively high velocity. The helicopter type of machine may be considered as the limit of the aeroplane when, by constantly increas- ing the speed, the area of the supporting surfaces is continuously reduced until it practically disappears. We may then picture a racing aeroplane propelled by great power, supported largely by the pressure against its body, and with its wings reduced to mere fins which serve to guide and steady its motion. In other words, starting with the aeroplane type, we have the dirigible balloon on the one hand as the tonnage increases, and the helicopter type on the other extreme as the speed increases. Apparently, therefore, no one of these forms will be exclusively used, but each will have its place for the particular work required. * * * 9 AVIATION IN FRANCE IN 1908.2 By PrerRRE-RoGER JOURDAIN, Member of the Aero Club of France, General Secretary of the Aero Club of Vichy. The science of aviation may be said to have originated with the French. Itisnotanewscience. As far back as 1742 there is authentic record of mechanical flight by man. In that year the Marquis of Bacqueville, 60 years old, hurled himself from his house top, glided a distance of 300 meters, and landed unceremoniously on a laundry boat moored along the banks of the Seine. Later came the isolated experiments by Blanchard (1753-1809) and by Degen, and aviation was for the time forgotten. Henson, in 1843, and Du Temple, in 1857, constructed the first fly- ing machines of rational design. These embodied in embryo the main features of some of our present machines, yet nothing was accom- plished with either of them. Then came the profitable agitation of the subject aroused in 1863 by Nadar, who, relying on the experiments of Ponton d’Amécourt and of Lalandelle, revolutionized European ideas by his well-known exposition of the science of aerial navigation. Nadar pointed out that up to that time the balloon must be held responsible for the lack of progress in mechanical flight, and that to actually fly it was essential that the apparatus be heavier than air. In his researches he had the support of M. Babinet, member of the institute. Then avia- tion again dropped from public notice. Although forgotten by the public, several investigators, among them Penaud, de Villeneuve, Tatin, and Marey, were conducting the first series of scientific studies on the flight of birds, which are still consulted with profit. Finally “Conference under the auspices of the association of former pupils of the Faculty of Sciences of Paris, in the large amphitheater of the Sorbonne, Decem- ber 19, 1908, M. Appell presiding. Translated, with permission, from the Revue Scientifique, Paris, February 18, 1909. 145 146 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. came the experiments by Lilienthal, Maxim, Langley, and Chanute, from 1892 to 1896. Specifically, what is the problem of aviation? It consists in launching a heavy body from the earth and in maintaining and guiding it in the air through purely mechanical means. Aviation has also been defined as the science of flying with machines heavier than air, as distinguished from aerostation, the science of ballooning, with apparatus lighter than air. It is the solution of this difficult problem of flying that men have sought for a number of years. Three different solutions of the problem have been proposed: One is in servile imitation of nature, that represented by the orthopter or wing machine. The second is a purely artificial conception, that of the helicopter or screw machine. The third is that of the aeroplane, which may be considered as a compromise, or a combination of the first two systems. The wing machine is, as I have stated, a servile imitation of nature. It is equipped with moving wings, and the machine is lifted by the reaction from the flapping of these wings. One of the principal representatives of this type is that designed by Blanchard even before Montgolfier’s hot air balloon; and, if rumors may be believed, secret experiments are now being conducted in Belgium with the La Hault type of this machine. In these wing machines the amount of force upon the air is normal and applied directly, so as to raise the apparatus vertically. It is at once evident that of the two motions in the flapping of the wings, the downward stroke causes the machine to move upward, while the up- ward stroke rather retards this movement. The attempt has been made to overcome this difficulty by the use of valves in the wings that open when the wing is raised and close when it is lowered. None of these machines, however, has given satisfactory results. The second type is the helicopter, or screw machine, a purely arti- ficial conception. Paucton was the first to suggest the application of the principle of the screw to aerial navigation, but it remained for de Lalandelle and Ponton d’Amécourt to actually experiment with this system and obtain the first practical results. The principle of this system is that of a screw turning upon a vertical axis, and it is the reaction of the air during the movement of the screw that should balance or overcome the weight of the apparatus and cause it to rise. These machines are very complicated. Whenever a force is applied to a medium such as air, there results a reaction equal to the action AVIATION IN FRANCE—JOURDAIN. TAs? first brought to bear. The screw, and consequently the whole machine, sustains from the air upon which it acts, a reaction equal to, but in the direction opposite to, that which it exercises. If we havea screw turning in a certain direction, the whole apparatus, upon the stability of which we rely to force the turning of the screw against the air, will tend to turn in the opposite direction as the result of a reactive force equal to that exercised by the screw. To overcome this tendency the attempt was made to increase the inertia of the machine by attaching vertical planes or surfaces in such a manner as to retard its rotative movement. But these large surfaced vertical planes are cumbersome and heavy. With laudable persistency investigators have devised a second method more advantageous than the first, which consists in the use of two screws turning in opposite directions, so that the effect of the reaction of the air on one screw is neutralized by the reaction on the other. Such an apparatus is capable only of lifting and sustaining itself in the air; it can not move horizontally. For this movement it must be supplied with a third screw, or propeller, mounted on a horizontal axis. This forms still another complication, for the use of only two sustaining screws is a minimum depending on the weight of the machine. And since the size of the screws is limited by considera- tions of strength their number must be increased, always in pairs, to four, six, or eight. M. Cornu in 1907 succeeded in lifting two passengers vertically. To obtain a horizontal movement M. Breguet attached to his machine cloth planes inclined at an appropriate angle, and it was through the reaction of the air from the vertical displacement on these planes that this apparatus was designed to move forward. Let us now examine the third solution, that of the aeroplane, which, as I have said, is a compromise or a combination of the first two systems, In the aeroplane the principal parts are comprised in an inclined surface, and it is this inclined surface gliding at a certain speed into the wind that sustains the machine. The total reaction of the air upon this surface resolves itself into two components—the resistance to horizontal advancement and the vertical thrust. These two forces are proportional to the square of the speed of propulsion and the area of the plane surface. Thus, if a given speed is doubled, we bring to bear on a given surface area, a force equal to the square of the force at the initial speed. This is the reason for the efforts to attain a greater speed, a speed which depends upon the power of the engine and screw of motor-propelled machines. 148 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. ELEMENTARY THEORY OF AVIATION. (After M. Armengaud, jr.) w3nw ee = = SS ee ‘ V. Pressure ‘10f Wand Ril eR ING P Fig. 1. R = resistance of air per square meter. S = sustaining surface. V = speed, assuming horizontal displacement in calm air. i = angle of attack. P = weight to be sustained and driven forward. Jf = horizontal component of the resistance or the force opposed to horizontal motion. P’ = vertical component, or reaction making up the sustaining force, and equal Ko) len T =elementary work in the case of a plane. ‘© = total work. K = coefficient of resistance of the air. LAW OF VARIATIONS OF THE RESISTANCE OF THE AIR FOLLOWING THE ANGLE OF ATTACK, N; =Resistance of the inclined plane making the angle i. Noo=Resistance of the perpendicular plane to advancement. sin? 7 (Newton and Euler). sin 2 (Marey). t Lean 3 (Rayleigh). NER rae: mae j (Gerlach). ar (Duchemin). sin 7 [a—(a—l) sin?7] (Renard). FORMUL. In the case of a narrow plane. R=KSY? (plane perpendicular to V). R;=KSYV? sin 7 (inclined on V). AVIATION IN FRANCE—JOURDAIN. 149 P=R; cos i=KSV? sin 7 cos i or $ KSV? sin 2i. ier eas KS sin 2i f=R; sin 1=KSY? sin? 7. 122 ~ S=K8V? cos? i Saas = —— ae tems 7 V—KSYV® sin? 1. _KS\4P*sin®i VERE S2igin2 027 Whence: Pp? T=KgvV cos’ i By eliminating V we have— ae So peniee om cos i¥ KS ae In case of the aeroplane. F=total force of movement. =force required to overcome resistance to advancement. K’=coefficient of resistance of the air to advancement. S’=ideal surface corresponding to framework, with motor, rigging, aviator and equipment. Jo be SON. Fast’. B=(FHINV. — = 4Q/ 73. To secure the minimum value of ‘6 the derivatives may be used with the following result: ve Pp? a dv. KSV? cos? aeiets Tie) aes Whence: fH3f". Propulsion creates and accompanies sustenance. In this connection I wish to make clear one frequently disputed point in regard to aerial navigation—that is, as to the impor- tance of the part played by the wind. As far as the aeroplane is concerned this is reduced to a minimum. As a matter of fact, the governing feature of an aeroplane is the speed of the machine itself against the air. If the air produces a pressure that is negative, or of no effect at all, it will influence only the horizontal displacement of the machine; the vertical displacement will depend always on the speed of the aeroplane itself. If the speed of the wind blowing against the machine is equal to the machine’s own speed, the aeroplane will rise but will not advance; it will fly and yet be stationary in the air. If there is no opposing wind, the machine will move hori- zontally at a rate equal to its own speed; if the wind blows in the direction the machine is going, the rate of advance of the aeroplane will be the sum of its own speed and of the speed of the wind. 150 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. This solution of the problem is, a priori, better than that offered. by the wing or screw machines. In fact, in applying the principle of the inclined plane, instead of lifting directly the total weight of the machine, it is necessary to, bring into play forces proportional only to one-eighth or one-fifth of this weight. I said this machine was in a way a compromise or combination. We find in it, in fact, both an imitation of nature and an intervention of artificial contrivances. If we observe the great soaring birds, such as the vulture and the sea gull, we see them often remain motionless in the air, their wings stretched, or even glide forward without flapping their wings. This is true only under certain circumstances, and is what we call “le vol a la voile” (sailing flight). It is really an optical illusion, for if we substitute for our eyes a cinematograph or instruments of study, such as those designed by Marey, we should be able, so to speak, to dissect the flight of the bird, and we should find that the tips of the wings are slightly moved from time to time. These movements of the tips of the wings are supplanted in the machine by the screw propeller. The propeller furnishes the same propulsion as that secured by the wings of the bird. Consequently, a machine con- structed in this manner, with a plane suitably inclined, and a sys- tem of motor propulsion, should be able to lift itself in the air. But to lift itself is not enough; it-should be capable of sustaining itself and of being guided; and there occurs the question, would such a machine equipped merely in this manner maintain itself in the air? No, it would not, for the air is essentially mobile; the wind, even when it seems most constant, is made up of pulsations, of layers of dif- ferent speeds, pressures, and densities. So, considering merely its re- sistance to the advance of the machine, since this resistance varies in proportion to the density of the medium, the aeroplane, subjected to these incessant fluctuations of the wind, will tend momentarily to change its state of equilibrium; it will undergo various move- ments, forward and backward, to the right and to the left, and will doubtless capsize. Furthermore, the steadiest atmospheric winds are filled with counter currents. If there is one principal current flowing in a definite direction, together with it are to be found accessory currents, oblique winds, winds rising from eddies caused by obstruc- tions of the ground, and the uneven slopes of the earth, trees, and houses. These currents striking the large planes on the side would tend to capsize the machine. There are three movements to be guarded against in an aeroplane: pitching, rolling, and a tendency to veer unexpectedly. We must be able to guide the machine at will. This question of longitudinal and transverse equilibrium has been a source of trouble to our aviators for a long time. And during the present year, 1908, aviators have AVIATION IN FRANCE—JOURDAIN. 151 been divided into two schools, those who favor the system of gov- erned longitudinal equilibrium and those who prefer automatic longi- tudinal equilibrium. The school of governed equilibrium is made up of those who rely upon the pilot of the machine to overcome by constant maneuvering any movements out of the line of perfect balance. Take for instance the pitching. This movement, forward or backward, so familiar on shipboard would tend to make the machine shoot up or down. To overcome this pitching a movable horizontal rudder is used. This part of the apparatus is composed simply of a miniature reproduction of the sustaining plane and is usually placed in front quite a distance from the center of gravity. This plane is pivoted on an axis and can be inclined at the will of the pilot. If the machine tends to pitch downward, the pilot, by merely increasing the angle of the plane, lifts the front part of the machine; the whole apparatus follows this movement and assumes a horizontal position, which is the posi- tion of equilibrium. To overcome rolling, the machines, even those whose longitudinal balance is a governed one, generally have a certain arrangement which we might call automatic, embodied in the angle made between the two planes following the longitudinal axis of the machine. This angle reduces to a certain extent the amplitude of the oscillation. To overcome the rolling movement the aviator acts exactly as in the case of pitching; he inclines the wing on one side or on the other. He can incline either the whole wing by warping it, or perhaps only a portion of it, the tip of the wing only being made movable. The governing motion is the same; if the machine begins to fall to the right or to the left, it is necessary only to give a greater inclination to the wing on the side toward which the aeroplane is falling in order that it may right itself. To prevent unexpected veering, there is a tail in the form of a cross which acts like the feathers of an arrow and insures true direction. A machine of governed equilibrium thus composed of a plane and a system of motor propulsion and of an arrangement to avoid pitch- ing, rolling, and veering can rise and maintain itself in the air, but it is a dangerous machine. To follow the very happy expression of M. Painlevé, it is “a veritable thoroughbred of the air ” which needs a jockey with plenty of nerve. The principal examples of this type are the Wright, the Blériot, and the Robert Esnault-Pelterie ma- chines. The Wright machine, however, although of governed equi- hbrium, differs from the ideal type that I have just pictured in that it is a biplane. The real difference between a monoplane and a biplane, and the reason why some aviators prefer the latter to the former is because, 88292—sm 1908——11 152. ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. with equal surface areas, the biplane is much easier to construct, especially when, as is the practice to-day, rigid surfaces are sought. The biplanes are also more compact than the monoplanes, and permit the use of an equal area of wing surface with only half the spread. Furthermore, equilibrium is preserved much more easily in a biplane. The underlying principles of these phenomena have not yet been completely explained. I shall confine myself to recalling the ideas of Chanute on the cellular forms (biplanes in compartments), ideas apparently well founded. Chanute holds that an air current at high speed confined by the walls or planes of the apparatus offers great resistance to any lateral displacement. It is somewhat similar to the action of the gyroscope, or rather the action is similar to that in a hose from which water is rushing out at a great speed and which is difficult to move. The same principles govern aeroplanes. Another detail: We have said that aeroplanes are sustained in the air by means of plane surfaces. This is not absolutely accurate, since the sustaining surfaces, viewed in section, show a slight curve. This curve is the result of experiment. It was found that the best flights’ were obtained when the wings cut the air squarely with their front edges, and when the resistance of the air was used on surfaces inclined gradually in greater degree. Air is so complex a medium and one that we really understand so little that it is only by long and careful experiment that the proper curve of the wings has been determined. The Wright brothers and the Voisin brothers spent several years determining this question. The Voisins experimented with a power- ful electric fan, capable of generating a very swift current of air, in front of which they placed linen surfaces mounted on frames with various curves. They weighted these and then measured the reaction of the air current on the surfaces. This method of experiment led them to select the degree of curve adopted on all their machines, par- ticularly those for Delagrange and Farman. Let us now examine the working of the Wright machine. This machine is of the type whose balance is governed by the pilot. The aviator has in his hands two levers. The left one controls the front balancing planes, or horizontal rudder, and this lever is constantly in motion. They are movements of very short amplitude (85 centi- meters forward and 35 centimeters backward, a total amplitude of only 70 centimeters), and that is sufficient to govern the pitching tendencies of the machine. The operation of this requires an atten- tion so close that the least slip would be fatal. It is similar to oper- ating the handle bars of a bicycle, moving to the right or left to retain the balance. The right-hand lever controls the vertical rudder and the warping of the wings. If the machine leans to one side, the operator increases the inclination of the wing on that side and this rights his machine. The simultaneous movement of the rear AVIATION IN FRANCE—JOURDAIN. 158 vertical rudder prevents the apparatus from changing its direction, as it would tend to do on account of the greater resistance endured by the wing that is warped. Great fears of fatalities were expressed when experiments in aviation were first undertaken, and I have frequently heard well- meaning persons say: “ But there is no future for aviation, because it is so dangerous. You can rise, but you can not descend; you may ride in a machine sustained in the air only by virtue of its great speed. To descend, you must slow down, and since the machine will no longer be sustained in the air, you will fall. Even though you are flying only at a moderate height a catastrophe will surely result. If, on the other hand, by using your horizontal rudder, you should approach the earth, your speed still being 70 or 100 kilometers an hour, when you reach level ground your aeroplane will come in violent contact with the earth, as an automobile would smash into a wall. In any case there would be a catastrophe.” Experience has proven the falsity of these fears: Neither one nor the other of these methods of descent is relied on exclusively. The angle of inclination of the planes is diminished at the same time that speed is lessened, and thus descent is made gradually, until at the last moment, with a slight luff up in the air, the machine alights gently, like a bird, on the ground. From the statements of M. Painlevé these landings have been quite sure, quite gentle, and at the same time much more easily accomplished than certain balloon landings of which I bear sad recollections. The second school of experimenters, those who prefer automatic longitudinal equilibrium, has as its principal exponents the Voisin brothers, two men who may truly be ranked among the creators of the science of aviation in France. The followers of this school have taken upon themselves to produce a machine which by its form alone will be stable and will automatically retain its position of equilibrium. They have attempted to realize this ideal so far as longitudinal equilibrium is concerned by the great longitudinal spread they have given to their machines. To secure transversal equilibrium they have utilized quite happily the ideas of Chanute and Hargrave, embody- ing the use of compartments. Santos Dumont, first of all, had an apparatus built composed of six sustaining compartments and one compartment for steering and bal- ancing, but the large number of vertical sides was superfluous, for these serve only to make the machine more stable and do not aid in sustaining it; consequently they are dead weight and useless. This school has retained the general idea of Santos Dumont, but has greatly simplified it. For instance, the principle of the compartment is still found in the Voisin aeroplane, but the compartment is reduced to useful dimensions, We likewise find the characteristic balancing 154 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. compartment, the question of the surface area of which is an impor- tant one. Asin the Santos Dumont type, it is placed well to the rear of the center of gravity, but it is fixed. It would appear that in this class of machines there is secured perfect automatic stability. There are no lateral oscillations. Even at speeds of 70 kilometers an hour the balance remains perfect, since speed itself enhances the stability. Some experimenters, however, still object that the compartment offers a great resistance to the turning of the machine. In this connection I beg leave to recall the following incident: Wright is not the only aviator who has made flights with a fellow- passenger. French aviators have carried passengers on several oc- casions. Farman in particular, at Ghent, made a flight of 1 or 2 kilometers with M. Archdeacon, vice-president of the Ligue aérienne. At Mourmelon Farman repeated this exploit in company with M. Painlevé, although in this case, owing to lack of room, M. Painlevé hung onto the frame and, as he says, nearly on M. Farman’s back. In spite of the abnormal position of the passenger, however, the ma- chine preserved a perfect equilibrium. It is much easier to manage this machine than the one whose equi- librium is controlled, since we have here only the front balancing planes and the vertical rudder to manipulate. There are no levers, but a simple automobile steering wheel moving in two directions—one of rotation, which governs the vertical rudder, and a sliding forward and backward in a groove of the whole steering gear to govern the front horizontal rudder. There is nothing to do when sailing straight ahead, and it is necessary to use the balancing planes only to rise. To descend, one slows the engine. This is a theoretical demonstration. In actual practice those who have managed these machines have certainly evidenced great coolness and have accomplished a very delicate task. The delicacy of the task is caused chiefly by the poor action of our present-day motors. -As soon as the ideal motor is attained the French aviators may secure as satisfactory results as the Americans. It is hardly probable that we shall witness any agreement between the two schools of aviators. In fact, those who favor governed equilibrium have realized a machine whose flight is analogous to that of a bird, while those who prefer automatic equilibrium are arriving nearer the form of flight of an arrow. [ach class of experimenters has striven toward a different ideal, and each has secured a satisfactory result. One class should not be criticised to the detriment of the other, but both should be praised without reserve. The Wrights and the Voisin brothers are not the only aviators, for to-day in France they are so numerous that it is impossible here to name them all. New experimenters come to the front daily, each filled with laudable enthusiasm, Certain names, however, force them- AVIATION IN FRANCE—JOURDAIN. 155 selves upon our attention: That of M. Robert Esnault-Pelterie, well known for his monoplane with warpable wings, and for his excellent R. E. P. motor, and also the names of the untiring Blériot, of Gastam- bide, of Pischoff, and of Zens. Among those experimenting with biplanes I may mention Dela- grange, Farman, Ferber, who with a 1904 machine nevertheless in 1908 won the third prize for the 200-meters contest at Issy-les-Moli- neaux, Goupy with his triplane, and finally Moor-Brabazon, in whom should be placed the greatest confidence. The balance sheet for the year 1908 shows great advancement. It was only on January 13 that the record for a kilometer was established by Farman at Issy-les-Moulineaux, in one minute and twenty-eight seconds. On March 21 he beat his record for 2,004 meters in three minutes and thirty-nine seconds. Delagrange, on April 11, at Issy, covered 3,925 meters in six minutes and thirty seconds. ‘Then he went to Italy and twice in succession—on May 30 and June 22—flew for a quarter of an hour. He returned to France, and after a well-earned period of rest, during which Farman in his turn broke the record for a quarter of an hour (prix Armengaud, in July), he covered—on Sep- tember 6, at Issy—24,125 meters in twenty-nine minutes, fifty-three and three-fifths seconds. How barely he missed a half hour! Delagrange is a veteran aviator. He had his machine built in 1906. On three occasions he has made flights of a quarter of an hour, even before Farman, a half an hour at Issy, and since then he has on three occasions flown for half an hour, twice breaking Wright’s record, when Wright lengthened the time of his flights. Wilbur Wright, as is well known, began his flights in France in the middle of the summer of 1908, and in his first trials proved himself a master. It is true that he has experimented a long time, but we should bow before the commendable spirit he has shown and admire his perseverance and courage. More recently Wright flew for two hours, covering more than 100 kilometers. The greatest honors at the end of the year 1908 will probably not go to French machines, but they have accomplished so much, and have made such rapid progress that we can well have confidence in them. Delagrange covered 24,125 meters and Farman 27,000. We may say, in general, especially since the two admirable flights of Farman and Blériot, that aviation has now become a_ practical science.? *Since the first publication of this paper our prophecies have been amply fulfilled. Although the Voisin biplanes have not succeeded in beating the Wright records, they have at least proved their worth in daily flights varying from 15 to 50 kilometers. The trials of Santos Dumont in his new small mono- plane, La Libellule, should also be mentioned, as well as the remarkable flights 156 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. There are still, to be sure, certain important questions to be settled, among others that of proper motors, a subject in which automobile manufacturers have not as yet taken special interest. More attention is now, however, being paid to motors in France, for the advent of the motor used by the Wrights has roused us from our apathy. Thus far we have only seen at work the Antoinette and R. E. P. motors. Renault has built an air-cooled motor which still needs certain im- provements. The Dutheil, Chamers, and Anzani motors are also de- serving of mention. Finally, at the exhibition this year there was opportunity to exam- ine some new models, which in principle seem interesting, but of which nothing can be said until we have seen them actually work in the air. At present the motor question remains to be settled, and surely will be in 1909. It is the weak point in French flying machines. Ifa machine can fly for 24 kilometers, with a good motor there is no reason why it should then stop, unless it be to renew the supply of fuel, oil, or water. Our motors, however, so often fail through a tendency to miss the spark, or through the breaking of a valve, or the heating of a bearing. As soon as our motors for flying machines are as perfect as those used in present-day automobiles, we shall be able to fly at will. And this is not all; we should likewise secure a more efficient use of sustaining surfaces. We should keep constantly in mind, following the advice of M. Tatin, the fact that the aeroplane is a projectile, and should strive in every possible way to decrease resistance to progress through the air. In the aeroplane of Santos-Dumont, built in 1906, there was used a motor of 100 horsepower, Voisin had one of 50 horse- power, Robert Esnault-Pelterie one of 35 horsepower, and Wright’s engine is about the same power. Messrs. Koechlin and Pischoff have succeeded in lifting a monoplane and its aviator with a motor of only 16 horsepower. These men are now building in their shops an aeroplane which should fly with a 12-horsepower motor. We can not, however, be certain that it will rise, though the principle is correct.* At any rate, it seems probable that the aeroplanes of the future will be driven by motors of not more than 20 horsepower. The use of such high power is at present not advantageous, for the propellers are very difficult to construct, and they undergo a very fast rotation at speeds generating a centrifugal force that occasionally in May, 1909, at Chalons, of Latham, who, with his very successful monoplane Antoinette, from the Levavasseur shops, accomplished flights of over an hour’s duration, at an average speed of SO kilometers an hour, during rain storms and heavy winds. His machine, of 50 horsepower, and carrying one or two pas- sengers, is the most efficient machine we now have. Blériot at the present time is trying out a machine for four passengers (June, 1909). 4 Since been tried at Jurisy without great success (June, 1909). AVIATION IN FRANCE—JOURDAIN. SY! plays havoc with them. The circular traction, even in a light-weight propeller may be enough to shatter it or to tear out one of its blades. On the other hand, this circular traction gives a great rigidity to the materials used, inasmuch as the speed of rotation, being considerable, permits the use of propellers of very thin wooden blades, or of sheets of aluminum so thin that at rest they are actually supple. M. Chauviére has specialized in the study of this phase of the question. He has built propellers of turned wood, that are quite novel. This, however, is not the whole problem. At present we are using propellors with short pitch and a high speed, which do not give good results. Judging from our experience with steamships, this is because the short pitched propeller, turning too rapidly, creates a neutral space or vacuum in front of it and therefore does not take full hold of the medium in which it turns. In water it turns in its place without hardly advancing; this is what is called in French the phenomenon of “cavitation.” If the pitch be increased, there is generated a reversing force which can not be neglected even with the great inertia of aeroplanes. On the other hand, without altering the pitch of the propeller the efficiency may be enhanced by increasing its diameter, and the consequent volume of air upon which it acts. But here we encounter still another difficulty that arises from the necessary position of the driving apparatus in the flying machine, a position determined by other mechanical considerations, and this diffi- culty is embodied in the fact that a propeller’s diameter must be so limited that it will not touch the earth when the machine is on the ground. M. Voisin, who is as well informed as anyone on this subject, has mentioned having noticed in single long-pitched propellers, a partial elimination of the reversing force by the reaction of the spiral of air on the posterior compartment of the aeroplane; but nevertheless there is a marked tendency among aviators, which will probably be realized during the year 1909, to use two long-pitched propellers turning slowly. To come into popular use, the aeroplane should satisfy three neces- sary conditions. It should be easy to manage, it should not be too expensive, and finally it should be of some actual service. We may already say that the machines are not extremely difficult to manage, and that, therefore, is not a condition at which we should stop. M. Delagrange is a sculptor; he had never had experience in aviation and yet he quickly attained very satisfactory results. And, if M. Voisin is to be believed, M. Moor-Brabazon made even more remarkable a debut. Apprenticeship must certainly be longer in the Wright machine. Mr. Wright has undertaken to teach pupils in three months. One of 158 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. these pupils, the Comte de Lambert, now understands the working of the apparatus, but always makes his flights in company with Wright, who has not yet dared let him fly alone. It is true that with this type of machine, there must be accuracy of manipulation out of the ordinary to avoid ever-possible accidents. It is to be noted also that the Wright machines have not yet flown elsewhere than over open fields. As to the cost of the machines, it is at once evident that aeroplanes will be much less expensive than automobiles, for all that an aeroplane needs are surface areas of cloth*or of aluminum, a motor, and a pro- peller. There are no complicated gears made of special steel, for changing the speed and the differential, and there are no expensive pheumatic tires. A machine of the Wright and Voisin model now costs 20,000 francs, or about $4,000, but this price may be lowered. Competition will contribute to reduce the cost and we already have manufacturers who undertake to furnish machines to be delivered after trial for 5,000 francs, or $1,000.. I believe that this will be the common price for most aeroplanes in the future. In order, however, that aeroplanes may be of reasonable cost, there must be a demand for them, and to create a demand there must be a need for them. From now on, from the point of usefulness, it is evident that flying machines will render extraordinary service. They will permit direct and rapid transportation anywhere, and one need no longer hesitate to visit lands that to-day are difficult of access2 * * * Direct transportation is evident for there are no obstacles in the way; but as to the possible speeds to be attained, that is an open question. It is certainly possible to obtain very great speeds with an aero- plane. The action of an illimitable force, that of gravity, is at our disposal as soon as the machine is lifted above the ground, and it is always possible to convert into speed the accumulated potential energy, which is proportional to the weight of the machine and the altitude attained. At the present time the machines do not rise high enough to apply this method of conversion of power. They move forward only through the speed of their propellers. Blériot has thus reached 76 kilometers an hour, and Farman 78 kilometers an hour. These are medium speeds. Blériot has attained on certain occasions speeds greater than 100 kilometers an hour. During the year 1909 we shall certainly realize the speed of 200 kilometers an hour, and ten years “Tambert has since flown perfectly alone. Tissandier is a master and has flown for more than an hour; Capt. de Girardville as well, and Delagrange is learning. 6 Hubert Latham is learning aviation to explore Africa.—June, 1909. AVIATION IN FRANCE—JOURDAIN. 159 from now 300 kilometers may be attained. These figures? are those of M. Painlevé, member of the Academy of Sciences. There remains to be considered one other important question. It is not enough that machines be inexpensive, for if there be too great risk to safety people will not make use of them. There must be a certain degree of security. I have heard it said: “The aeroplane has made trips all right, but you are at the mercy of your motor. What will happen if your motor fails to spark, a thing which is possi- ble at any moment? Suppose you are flying over a city, what would you do?” The aeroplane, say some persons, should therefore fly only above rivers, plains, and highways. What interest would there be under such limitations? As a matter of fact, if the motor stops accidentally, the aeroplane does not fall; it descends as I have said, along the line of an inclined plane, and the angle at which it will descend depends largely on the perfection of the machine and the skill of the pilot. We can admit, generally, that the ratio of the height of the fall to the course covered, measured on a horizontal projection is about 1 to 7, and within a year the ratio of 1 to 10 will surely be attained. Thus the aeroplane, stopped at a height of 100 meters, has at least five or six hundred meters to descend in, not only directly in front but to the right or the left. The machine will therefore be in the center of a circle of at least a kilometer in diameter. It would be quite extraordinary if a suitable place to land could not be found within such limits. (I do not include the hypothesis of soaring, which is beyond the scope of this discussion.) The answer simply is, that if there is fear of a failure of the motor in crossing over cities one should keep at a reasonable height. * * * “Not yet confirmed by experiments.—June, 1909. nt is WIRELESS TELEPHONY. [With 20 plates. ] By R. A. FrESSENDEN.? PREFACE. The discussion of the theory, practical operation, and possibilities of wireless telephony is facilitated by first briefly considering the history of the development of wireless signaling generally. BRIEF HISTORY OF THE DEVELOPMENT OF WIRELESS SIGNALING. Introduction. preparing this note it has been considered best, for the sake of accuracy, to refer to published results, such as scientific articles or theses or patent specifications. For the sake of brevity, references to work done in repetition of previously published work have asa rule been omitted. So far as possible, the expression of per- sonal opinion has been avoided in this section of the paper, the object being to gather’ together in concise form the facts known in regard to the development of the art. With the exception of Munk’s original paper, which could not be obtained, all references have been verified by consulting the original publications, a work of some labor, and if any omissions or mistakes have been made, data for their correction will be much appreciated. ORIGIN AND DEVELOPMENT OF Op or DAMPED WAVE-COHERER Meriop (eERIOD 1838-1897). Joseph Henry, to whose work the development of wire telegraphy owes so much, was the first (1838-1842) to produce high frequency “Copyright, 1908, by A. I. E. E. Reprinted, by permission, from Proceed- ings of the American Institute of Electrical Engineers, Vol. XXVII, No. 7, July, 1908, New York. >A paper presented at the Twenty-fifth Annual Convention of the American Institute of Hlectrical Engineers, Atlantic City, N. J., June 29, 1908. 161 162 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. electrical oscillations, and to point out and experimentally demon- strate the fact that the discharge of a condenser is under certain con- ditions oscillatory, or, as he puts it, consists “ of a principal discharge in one direction and then several reflex actions backward and for- ward, each more feeble than the preceding until equilibrium is attained.” @ This view was also later adopted by Helmholz,’ but the mathemat- ical demonstration of the fact was first given by Lord Kelvin in his paper on “ Transient electric currents.” ¢ In 1870 Von Bezold discovered and experimentally demonstrated the fact that the advancing and reflected oscillations produced in con- ductors by a condenser discharge gave rise to interference phenomena.* Profs. Ehhu Thomson and E. J. Houston in 1876 made a number of experiments and observations on high frequency oscillatory discharges.¢ In 1883 Professor Fitzgerald suggested at a British Association meeting’ that electromagnetic waves could be generated by the discharge of a condenser, but the suggestion was not followed up, possibly because no means were known for detecting the waves. Hertz’ discovered a method of detecting such waves by means of a minute spark-gap, and before March 30, 1888, had concluded his remarkable series of researches, in which for the first time electro- magnetic waves were actually produced by a spark-gap and radi- ating conductor and received and detected at a distance by a tuned receiving circuit. Hertz changed the frequency of his radiated waves by altering the inductance or capacity of his radiating conductor or antenna, and reflected and focused the electromagnetic waves, thus demonstrating the correctness of Maxwell’s electromagnetic theory of light. Lodge later in the same year read a paper on the “ Protection of buildings from lghtning,”’” before the Society of Arts, in which he described a number of interesting experiments on oscillatory discharges. Great interest was excited by the experiments of Hertz, primarily on account of their immense scientific importance. It was not long, however, before several eminent scientists perceived that the property « Scientific writings of Joseph Henry, Smithsonian Institution. 6 Helmholz, ‘“ Erhaltung der Kraft,’ Berlin, 1847. ¢ Kelvin, Philosophical Magazine, June, 1853. @Von Bezold, Poggendorff’s Annalen, 140, p. 541. € Journal Franklin Institute, April, 1876. f Witzgerald, “On a method of producing electromagnetic disturbances of comparatively short wave lengths.” Report of British Association, 1888. 9 Hertz, “ Hlectric waves.” h Lodge, Society of Arts, 1888, WIRELESS TELEPHONY—FESSENDEN. 163 possessed by the Hertz waves of passing through fog and mate- rial obstacles made them particularly suitable for use for electric signaling. Prof. Elihu Thomson, in a lecture delivered at Lynn, Mass., on “Alternating currents and electric waves,” in 1889, suggested this use. Sir William Crookes in the Fortnightly Review for February, 1892, discussed the matter in some detail. I quote his statement in full, as it shows what a clear conception he had of the possibilities and obstacles to be overcome: Here is unfolded to us a new and astonishing world, one which it is hard to conceive should contain no possibilities of transmitting and receiving intelligence. Rays of light will not pierce through a wall, nor, as we know only too well, through a London fog. But the electrical vibrations of a yard or more in wave length of which I have spoken will easily pierce such medium, which to them will be transparent. Here, then, is revealed the bewildering possibility of telegraphy without wires, posts, cables, or any of our present costly appliances. Granted a few reasonable postulates, the whole thing comes well within the realms of possible fulfillment. At the present time experimentalists are able to generate electrical waves of any desired wave length from a few feet upward, and to keep up a succession of such waves radiating into space in all directions. It is possible, too, with some of these rays, if not with all, to refract them through suitably shaped bodies acting as lenses, and so direct a sheaf of rays in any given direction ; enormous lens-shaped masses of pitch and similar bodies have been used for this purpose. Also an experimentalist at a distance can receive some, if not all, of these rays on a properly constituted instrument, and by concerted signals messages in the Morse code can thus pass from one operator to another. What, therefore, remains to be discovered is: Firstly, simpler and more certain means of generating electrical rays of any desired wave length, from the shortest, say of a few feet in length, which will easily pass through buildings and fogs, to those long waves whose lengths are measured by tens, hundreds, and thousands of miles; secondly, more delicate receivers, which will respond to wave lengths between certain defined limits and be silent to all others; thirdly, means of darting the sheaf of rays in any desired direction, whether by lenses or reflectors, by the help of which the sensitiveness of the receiver (apparently the most difficult of the problems to be solved) would not need to be so delicate as when the rays to be picked up are simply radiating into space in all directions and fading away according to the law of inverse squares. T assume here that the progress of discovery would give instruments capable of adjustment by turning a screw or altering the length of a wire, so as to become receptive of wave lengths of any preconcerted length. Thus, when adjusted to 50 yards, the transmitter might emit, and the receiver respond to, rays varying between 45 to 55 yards and be silent to all others. Considering that there would be the whole range of waves to choose from, varying from a few feet to several thousand miles, there would be sufficient secrecy, for curiosity the most inveterate would surely recoil from the task of passing in review all the millions of possible wave lengths on the remote chance of ulti- mately hitting on the particular wave length employed by his friends whose correspondence he wished to tap. By “coding” the message even this remote chance of surreptitious straying could be obviated, 164 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. This is no mere dream of a visionary philosopher. All the requisites needed to bring it within the grasp of daily life are well within the possibilities of discovery, and are so reasonable and so clearly in the path of researches which are now being actively prosecuted in every capital of Hurope that we may any day expect to hear that they have emerged from the realms of speculation into those of sober fact. Even now, indeed, telegraphing without wires is possible within a restricted radius of a few hundred yards, and some years ago I assisted at experiments where messages were transmitted from one part of a house to another without an intervening wire by almost the identical means here described. The statement in the last paragraph of the quotation refers to the work of Prof. David E. Hughes. Professor Dolbear also suggested the same thing in an article in Donahoe’s Magazine, March, 1893. In fact, the idea of using Hertzian waves for wireless telegraphy seems to have been quite widespread in the years immediately fol- lowing Hertz’s publications. Fairly efficient means of generating electromagnetic waves of any desired length had been made known by Hertz. Vertical antenne connected with the ground had been previously used for sending and receiving by Dolbear in 1882 in connection with his system for tele- graphing by electrostatic induction” and also later by Edison and others. Hertz’s receiver, the minute spark-gap, was not suited for wireless telegraphy, and before any telegraphic work could be done a suitable receiver had to be found. The fact that tubes containing conducting powders had their resistance altered by the discharge of a Leyden jar and that the original resistance could be restored by tapping the tube was first noted by Munck. in 1835.¢ In 1890 Branley showed that such a tube would respond to sparks produced at a distance from it.? In 1892, at a meeting of the British Association at Edinburgh, Prof. George Forbes suggested that such a tube would respond to Hertzian waves. In 1893 Professor Minchen demonstrated experimentally that such powders would respond to electro-magnetic waves generated at a distance. He used a battery and zglimomaetes shunted around the powder to detect the effect of the waves. @¥or report of this work see Electrician, May 5, 1899. bDolbear, United States patent No. 350299, March 24, 1882. ¢ See Guthe ‘‘ Coherer action,’ Transactions of the International Electrical Congress, St. Louis, 1904, p. 242. Munck., Poggendorff Ann., 1838, vol. 48, p. 1938. @Branley, Comptes Rendus, 1890, p. 785, and 1891, p. 90. € Minchen, Proceedings Physical Society, London, 1893, p. 455, WIRELESS TELEPHON Y—FESSENDEN. 165 Sir Oliver J. Lodge on June 1, 1894, delivered a lecture before the Royal Institution.*. In this remarkable lecture Lodge described among other things the following: 1. The filings coherer. 2. The filings coherer in hydrogen under reduced pressure (this in a note added July, 1894). 3. The automatic tapper back for the coherer. 4. The metallic reflector for focusing the waves. 5. The connection of the coherer to a grounded conductor, i. e., a gas-pipe system. 6. The method of making the coherer so connected respond by setting up oscillations in a separate grounded system, i. e., a hot-water pipe system, in another part of the building. 7. The method of detecting distant thunderstorms by connecting the coherer to a grounded gas-pipe system. In this lecture Professor Lodge stated that in his estimate the apparatus used would respond to signals at a distance of half a mile. Early in 1895 Professor Popoff,’ of Cronstadt, Russia, constructed a very sensitive filings coherer, one form of which was used in some surveying experiments by the Russian Government,’ consisting of iron filings suspended by a magnet and resting upon a metallic plate or cup. Other forms consisted of filings in glass tubes with platinum electrodes. He used early in 1895 the automatic tapping back mechanism and substituted for the galvanometer an ordinary tele- graphic relay. He operated this apparatus at a distance by means of a large Hertzian radiator. One terminal of his coherer was con- nected to a conductor fastened to a mast about 30 feet high on the top of the Institute building, and the other terminal of the coherer was grounded. At the conclusion of his paper, which is dated December, 1895, Popoff made the following statement: In conclusion I can express the hope that my apparatus, with further im- provements of same, may be adapted to the transmission of signals at a distance by the aid of quick electric vibrations as soon as the source of such vibrations possessing sufficient energy will be found. Among other experimenters who were working on this subject at the same time may be mentioned Captain Jackson, of the British Navy, and Mr. A. C. Brown. @Sir O. J. Lodge, ‘““ The work of Hertz,” Proceedings Royal Institution, June 1, 1904, vol. 14, p. 321. ® Journal Russian Physico-Chemical Society, vol. 27, April 25, 1895. CA. S. Popoff, “Apparatus for detection and registration of electrical vibra- tions,” Journal Russian Physico-Chemical Society, vol. 28, December, 1895, 166 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Marconi, on June 2, 1896, filed a provisional specification * showing two forms of apparatus, one similar to Lodge’s 1894 apparatus using ungrounded aerials for both sending and receiving and the other for use “ when transmitting through the earth or water ” substanvially identical with Lodge’s 1894 and Popoff’s 1895 apparatus, with tapper back, etc., and the receiving antenna only being grounded. Soon after, in July, 1896, Marconi arrived in England and made a number of experiments for the English post-office at Salisbury Plain and elsewhere, using ungrounded aerials and parabolic reflec- tors and succeeded in reaching nearly 2 miles. On March 2, 1897, Marconi filed the complete specification in which was included a statement that the transmitting antenna also could be grounded. Lodge filed a provisional specification showing radiating spheres, but no antenna, on May 10, 1897. The complete specification filed on February 5, 1898, shows as one form both antennz grounded and also the use of an inductance wound in the form of a coil for the purpose of diminishing the rate of damping of the waves. So far as is known little work was done in America during this period. The writer made some experiments in 1896 and in conjunc- tion with two of his students, Messrs. Bennett and Bradshaw, did considerable work on receivers of various types in the fall of 1896 and spring of 1897, the results of which were incorporated in a thesis.° Return to First PrrncipLes AND FounpDaATION, ON Lines ANTITHET- 1cAL TO Oxp, or New or SUSTAINED OscILLATION NONMICROPHONIC Recerver Metrnop (1898). Up to the year 1898, as may be seen from the above, the develop- ment of wireless telegraphy had proceeded along a single line. In that year, however, an entirely new method of wireless telegraphy was developed, characterized by a return to first principles, the aban- donment of the previously used methods and by the introduction of methods in almost every respect their exact antitheses. While the coherer is of more or less interest theoretically it is not adapted for use for telegraphic purposes. Responding as it does to voltage rises above a certain limit, it does not discriminate between impulses of different characters, and is therefore peculiarly suscep- tible to interfering signals and atmospheric disturbances, and the operation of coherer systems can not be guaranteed during the sum- @Marconi, Great Britain patent No. 12039, 1896. b Lodge, Great Britain patent No. 11575, 1897. ¢ Western University of Pennsylvania, May, 1897. WIRELESS TELEGRAPH Y—FESSENDEN. 167 mer months or in the Tropics. Roughly speaking, a coherer acts by starting an are and making a short circuit on the line every time a signal is received, which short circuit persists until it is broken by a blow from an additional mechanism, and such a method of operation is obviously far from practical. In addition, it is practically impos- sible to obtain sharp tuning in a local circuit containing a coherer ; its action is always more or less erratic, its electrostatic capacity vari- able, and it is insensitive. At the sending end the energy which can be liberated by the dis- charge of an antenna is limited, and in the form used prior to 1897 the dampening is so great that there are only a few oscillations per spark. Lodge,* by placing a coil of large inductance in the antenna, throttled down the amount of energy radiated per oscillation and so obtained with the same limited amount of energy derived from the charged antenna, an increase in the time of damping. Braun” patented the method of using a local oscillatory circuit connected to an antenna, the local oscillatory circuit having a much longer period than the natural period of the antenna and of a differ- ent order of magnitude. Such a system, however, does not radiate energy appreciably, and produces a damped wave. This dampening and the limited amount of energy obtainable by charging and discharging the antenna operates to prevent sharp tun- ing and working over long distances. The coherer is well adapted for working with damped waves, but the coherer-damped wave method can never be developed into a practical telegraph system. It is a question whether the invention of the coherer has not been on the whole a misfortune as tending to lead the development of the art astray into impracticable and futile lines and thereby retarding the development of a really practical system. The fact that no coherer-damped wave system could ever be de- veloped into a practically operative telegraph system, and the fact that it was necessary to return to first principles and initiate a new line of development along engineering rather than laboratory lines was perceived in America in 1898° and a new method was advised which may be called the sustained oscillation-nonmicrophonic re- ceiver method as opposed to the damped oscillation-coherer method previously used. “Lodge, Great Britain patent No. 11575, 1897. ‘Braun, German patent No. 11578, October 14, 1898. ¢ Hlectrical World, July 29, August 12, September 16, 1899, and Proceedings American Institute of Electrical Engineers, November, 1899, page 685, and November 20, 1906, page 781. 88292—smM 1908 12 168 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. FUNDAMENTAL DIFFERENCES BETWEEN THE OLD AND New WIRELESS ScHOOLS. The differences between the two methods are shown in tabulated form: Damped oscillation-coherer method. pustalned oscillation nonndcrophonie AVA Ses iepiaeomore Damped oscillations are produced at the | Sustained oscillations are produced at the sending end. sending end. SAU Dee Sac mataeicee The energy transmitted is obtained by | The energy transmitted is derived from charging the antenna and discharg- a local source and fed into the antenna. ing it. JAN cseincece cise A spark gap is used for producing the | An are or high frequency dynamo is gen- oscillations. erally used for producing the oscilla- tions. Bilin cesstcccce Imperfect or microphonie contact re- | Nonmicrophonic contact recéivers are ceivers are used. used. ; Biase seins The action of the receiver depends upon | The receiver response is determined by the voltage rise and is independent of the integral amount of energy received. the amount of energy received. Bigeeceececoees An open-tuned circuit is used for re- | A closed tuned circuit is used for re- ceiving. ceiving. Bide acemsecesee The receiving circuit is tuned to the | The receiving circuit may be tuned toa wave frequency only. group frequency as well as to the wave frequency. GMs 2s cemcecte In transmitting messages the production | The waves are preferably generated con- of the electromagnetic waves is inter- tinuously and the transmission accom- mittent. plished by changing the character of the wave. Olio 2 cescscesaee The wave energy flux is intermittent ....| The wave energy flux is constant. OBigosecesogagac A high voltage is used.....-..-.--.-.....- A low voltage is used. (Or CSAS SneBeceaS Comparatively short wave lengths are | Comparatively long wave lengths are used. used. (Cl Wienemeecoaeses The signals consist of dots and dashes, | The signals may consist of dots only, whose interpretation is fixed. whose interpretation depends on the station sending and receiving. DAS icc encunecs Antenns# are used adapted, roughly | The antennez are preferably arranged so speaking, to utilize the electrostatic component of the electromagnetic waves. as to utilize the other component of the electromagnetic waves instead of the electrostatic component. The history of these two antithetical lines of development will be treated of separately. DEVELOPMENT AND PERFECTING OF MICROPHONIC Receiver Mreruop SUSTAINED OSscILLATION-NON- (Prrtop 1898-1902). THE CURRENT-OPERATED RECEIVER. The first essential for the development of the system was, of course, a quantitatively responsive receiver. Several forms of this were tried, including the modification of the Boys’ radio-micrometer (consisting of a light thermo couple suspended in the field of a per- WIRELESS TELEPHON Y—FESSENDEN. 169 manent magnet and heated by radiation from a wire, which in turn was heated by the current to be detected) described by the writer at the Columbus meeting of the American association in 1897.2 This was abandoned in favor of Prof. Elihu Thomson’s alternating- current galvanometer,’ suitably modified for telegraphic work.° Among other forms of current-operated receiver may be mentioned the following: The hot-wire barretter,’? consisting of a minute platinum wire a few hundred thousandths of an inch in diameter and approxi- mately a hundredth of an inch in length. The term “ barretter ” was eoined for this device for the reason that it differs essentially from the bolometer of Langley in that it is arranged to be affected by external sources of radiant heat as little as possible instead of as much as possible, and to have an extremely small specific heat, an object not sought in the case of the bolometer. The liquid barretter,’ in which the change of resistance is effected by heating a liquid, the concentration of path being obtained by means of a fine platinum wire point. Some question has been raised as to the theory of operation of this device, but I think there is no question but that the effect is due to heat, though what per cent of the effect is due to change in ohmic conductivity by heat and what per cent is due to depolarization by heat is still, as originally stated by the writer,’ uncertain. The facts that the device operates prac- tically equally well irrespective of which terminal is connected to the local battery, and that the effect varies as the square of the alternating current (as a heat-operated device should do) instead of directly with the alternating current as a rectifier would do, and that depolarization is produced by-the heat, have been confirmed by Dr. L. W. Austin.’ The writer has experimentally determined the fact that though the electrical impulses may have a duration of less than a millionth part of a second, the change in resistance per- sists for approximately the ten thousandth part of a second, which would seem to show conclusively that the action is not a direct effect of the waves. The term electrolytic receiver has sometimes been applied to the liquid barretter. This is objectionable, as there are a number of electrolytic receivers. For example, the Neughschwender-Schaefer 2 * Hlectrician, June 24, 1904. >’ Elihu Thomson, United States patent No. 363185, January 26, 1887. ¢ United States patents Nos. 706786 and 706737, December 15, 1899. @United States patent No. 706744, June 6, 1902. € United States patent No. 727331, April 9, 1908. f Austin, Bulletin of the Bureau of Standards, vol. 2, No. 2. 9 Neughschwender, German patent No. 107848, December 18, 1898, and Schaefer, British patent No, 6002, 1899. 170 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. receiver, in which a number of microscopic filaments are produced between two terminals by electrolysis, which filaments are ruptured by the wave-produced oscillations, thus increasing the resistance; also the liquid coherer of Captain Ferrie, described by him as follows: 4 The same effect of self-decohering coherence has been determined for a contact of a metallic wire and a liquid conductor, acidulated water, contained in a glass tube of small diameter, and placed under the same conditions as the preceding. Always, the sensitiveness of this contact is very notably inferior to that obtained in the experiments disclosed above. The maximum sensitive- ness was obtained when the resistance of the imperfect contact was about 2,000 ohms and when the extremity of the metal wire scarcely grazed the meniscus of the liquid. The results obtained were better with a copper wire, attacked by the acidulated water, than with a platinum wire. This coherer probably acts through a chemical effect producing a thin film of gas and has never come into use, doubtless because, as Captain Ferrie points out, it is even less sensitive than the Marconi coherer. Also the rectifier of Pupin,’? in which the terminals are placed so closely together that practically no energy is absorbed in the receiver, in order that the rectified energy may be utilized outside in the external circuit, in opposition to the liquid barretter, where the position of the terminals is such that all the received wave energy is absorbed in the barretter for the purpose of producing a secondary effect, and so influencing the current in a shunted local circuit. METHODS OF OBTAINING SUSTAINED OSCILLATIONS. Spark-gap, and local oscillatory or “ tank” circuit—Prof. Elihu Thomson discovered that by using a transformer without an iron core (the well-known Elihu Thomson air-core transformer, later used by Tesla and others) and a spark-gap and condenser in the primary circuit, and with the secondary circuit suitably tuned great resonant rises of potential could be obtained. In 1892 he constructed such a transformer giving discharges 64 inches long.’ The same method was later used by Tesla? in his experimental researches and in his attempt to carry out Loomis’s ° method of trans- mitting a current through a hypothetical conducting stratum in the upper regions of the atmosphere. The device, suitably modified for wireless telegraphic purposes, so as to give, instead of a continuously cumulative rise of potential, an initial rise of potential followed by a gradual feeding in of the energy from the local circuit to supply the energy lost from radiation, “Blondel, L’Eclairage Electrique, September 29, 1900. +Pupin, United States patent No. 713044, January 4, 1898. ¢ Wlectrical World, February 20 and 27, 1892. @United States patent No. 645516, September 2, 1897. € Loomis, United States patent No. 129971, July 30, 1872. WIRELESS TELEPHON Y—FESSENDEN. ira! was made use of in 1898 for the purpose of producing prolonged trains of sustained waves. Various types of connection between the antenna and the local oscillatory circuit were tested, but it was found that the most efficient results were obtained by connecting the local circuit directly across the spark-gap.* The results of some comparative tests are here given. The figures in the column “ A” are for the local circuit connected directly to the terminals of the spark-gap, those in column “ B” are for an auto- transformer, those in column “ C” for a loose-coupled primary and secondary. A) Bi f HRS CY TLSTI Ve Sere ee a nee i eye oer al ree ee eee | 212,000 | 212,000] 212,000 PaMECCApACltyE (MivE hese otis aoc atae eons cee Nace nian Sascoece ceases cinema e 0. 072 0. 072 0. 072 REO WauLOULp lu Cy MAIN Oscar see cece seicesaccises nets sss cee atieeacee: 30 30 30 MAMRACUTEENIL) (AMPCLES) esas see ee eee eee sme sere ees Wister and Geitel, Wied. Ann. de Physik, vol. 52, p. 483. € Duddell, The Electrician, 1903, vol. LI, p. 902. @Wleming, Proceedings of the International Congress, St. Louis, 1904, vol. 3, p. 608. € Poulsen, United States patent No. 789449, June 19, 1903. f Austin, Bulletin of the Bureau of Standards, vol. 3, No. 2. 9 Oberbeck, Wied. Ann. der Physik, vol. 55, 1895. k Wied. Ann, der Physik, vol. 8, 1902. «Drude, Ann. der Physik, vol. 13, 1904. j Bjerknes, Ann. der Physik, vol. 44, 1891, and vol. 47, 1892. k United States application No. 251538, March 22, 1905. ’ United States application No. 271539, June 28, 1905. 176 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. The so-called “ thermoelectric receivers ” of Austin,* Pickard,? and Dunwoody.°¢ The “ audion ” of De Forest,’ a very interesting and sensitive de- vice, which though superficially resembling Professor Fleming’s recti- fier appears to act on an entirely different principle. The Cooper-Hewitt mercury receiver, about which little is known, but which appears to be very sensitive. The following are some of the later methods of producing sustained oscillations: The substitution of a number of ares in series having terminals of large heat capacity in place of the single arc in the arc method.° The use of regulating or “ fly-wheel ” circuits in connection with the are method.° The method of producing oscillations shown in plate 2, figure 1, by using two arcs and throwing the discharge from one side to the other alternately at a frequency regulated by the constants of the electric circuit.¢ The condenser dynamo!’ which consists of two radially slotted disks separated by a mica diaphragm, charged by a continuous cur- rent source of potential, and rotating in opposite directions. Two-phase high-frequency dynamo method. Commutator method." In this method the high frequency is pro- duced by means of a ball rotating at high speed on the interior sur- face of a commutator (pl. 2, fig. 2). The helium are method,‘ in which the are is produced in helium or argon or similar gases. The critical pressure method,’ in which the electrodes extend within a certain critical distance, depending upon the pressure used, so that the discharge always passes at the same voltage irrespective of the distance between the electrodes. Methods of siqnaling.—Continuous production of waves but chang- ing constants of sending circuit.” The inverted method of sending and the method of signaling by sending dots, the interpretation of which is determined by similar commutators at the sending and receiving stations. 4 Austin, United States application No. 319241, May 29, 1906. ‘Pickard, United States application No. 342465, November 8, 1906. € Dunwoody, United States patent No. 837616, March 28, 1906. @De Forest, United States patent No. 836070, January 18, 1906. € United States application No. 291787, December 14, 1905. f United States application No. 291739, December 14, 1905. 9 United States patent No. 793649, March 30, 1905. 4 United States application No. 316521, May 12, 1906. + United States application No. 351560, January 7, 1907. Jj United States application No. 355787, February 4, 1907. k United States patents Nos, 706747, September 28, 1901; 706742, June 6, 1902; 727747, March 21, 1903. Smithsonian Report, 1908.—Fessenden. -PLATE 2 Fic. 1.—APPARATUS FOR PRODUCING OSCILLATIONS. Fic. 2.—COMMUTATOR METHOD OF PRODUCING OSCILLATIONS. Smithsonian Report, 1908.—Fessenden. 5 PLATE 3. Fic. 1.—HARMONIC INTERRUPTER FOR DETERMINING VARIATION OF INTENSITY WITH CHANGE OF NOTE. Fig. 2.—WIRELESS TELEPHONE RECEIVER, WITH THIN COPPER DIAPHRAGM REPELLED BY RESISTANCE COIL OF 16 OHMS. Fic. 3.—TRANSFORMER USED IN TRANSMITTING CIRCUIT. WIRELESS TELEPHONY—FESSENDEN. C77 Duplex and multiplex methods.—A considerable number of these have been worked out, mostly operating either by balance methods ¢ or commutators.’ It is impossible to discuss all the various improve- ments, such, for example, as the method of indicating the busy and free state of a station, the methods of sending and receiving in one direction, the various types of aerials used for receiving the other components of the electromagnetic waves besides the electrostatic component, ete. Plate 3, figure 1, shows the harmonic interrupter for determining the variation of eee with change of note. Plate 3, figure 2, shows a type of receiver described in United States patent No. 706747, in which the telephone diaphragm is formed of thin copper and repelled by a fixed coil having a resistance of about 16 ohms. The principle of this receiver was discovered by Prof. Elihu Thomson. It has been used for wireless telephony for a distance of 11 miles with fairly satisfactory results. Plate 3, figure 3, shows a transformer used in the transmitting cir- cuit. The number of primary and secondary turns can be altered continuously, and also the degree of coupling. The wire is wound off from an insulating cylinder onto a cylinder of copper, and the cylinder of copper, forming a closed circuit secondary of the trans- former, annuls the inductance of that portion of the wire wound upon the copper cylinder. Plate 4 shows a group-tuned call; that is, a vibration galvanometer which operates a selenium cell and rings a bell when a call is received. Plate 5, figure 1, shows an apparatus for determining the best shape of coil for use with the heterodyne receiver. THEORY OF WIRELESS TELEPHONY. For wireless telephony three things are necessary : 1. Means for radiating a stream of electrical waves sufficiently continuous to transmit the upper harmonics on which the quality of the talking depends. 2. Means for modulating this stream ae waves in accordance with the sound waves. 3. A continuously responsive receiver, giving indications propor- tional to the energy received and capable of responding with suflicient rapidity to the speech harmonics. Work on the wireless telephone was commenced before a satisfac- tory means was discovered for producing sustained oscillations. To ascertain the number of sparks per second which was necessary to determine articulate speech, a phonograph cylinder was taken “United States application No. 366528, April 5, 1907. ’ United States patent No. 793652, April 6, 1905. 178 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. and grooves were cut in it longitudinally. It was found in this way that practical transmission could be accomplished with 10,000 breaks per second. It is believed now that this number is unnecessarily high, possibly owing to the fact that it was impossible to cut the grooves on the cylinder without producing ridges. The lower limit may be fixed in another way. Electrical circuits met with in actual working have resistance, self- inductance capacity, and leakance. Heaviside gave the differential equations for the pressure and current over such circuits when alternating voltages were applied, but no method of solution being known, the mathematical treatment of such circuits was restricted to cases where one of the constants was neglected, until Dr. A. E. Kennelly in a masterly series of papers gave the complete solution. The results were immediately found applicable to a great variety of problems, such as the transmission of signals through cables and of telephonic speech through various types of circuits. In this way Doctor Kennelly * by comparing the results obtained by Dr. Hammond V. Hayes” in practical telephonic transmission over loaded lines with the theoretical values of the current for dif- ferent harmonics showed that harmonics above 2,000 per second could be neglected for telephonic transmission. The writer has never succeeded in obtaining good talking with such a low frequency, but under favorable conditions fairly satis- factory speech may be obtained with 5,000 interruptions per second. For really good transmission, however, the radiation must be prac- tically continuous, for if the spark frequency is less than 20,000 per second there is a disagreeable high pitch note in the telephone, not noticeable perhaps at first but apt to become annoying with use. The most satisfactory way is, of course, to use a source of sustained oscillations. It fortunately happens that for wireless telephonic purposes it is inadvisable to use a wave frequency of less than 25,000 per second, on account of the difficulty in radiating energy with low frequencies. The receiver must, of course, be continuously responsive. If, for example, it had to be tapped back in order to restore it to the responsive condition, speech could not be transmitted. It must also give indications proportional to the energy received or the character of the speech will be distorted. It must also respond with sufficient rapidity. If, for example, it takes a thousandth of a second to restore itself to its original resist- “Kennelly, ‘Distribution of pressure and current over alternating-current circuits,’ Harvard Engineering Journal, 1906, p. 43. b Hayes, “Loaded telephone lines in practice,” Electrical Congress, St. Louis, vol. 3. Transactions International “G3SAIS03Y SI T11VO NAHM 114g V SONIY HOIHM ‘11390 WNINATSS V ONILVYSdO YSLAWONVAIVS) NOILVYSIA ‘TIVO GSNNL-dNOUS VW ‘p alvid *uapusessa j—'gQ6| ‘Hoday ueiuosyyiLuS Smithsonian Report, 1908.—Fessenden PLATE 5. Fic. 1.—APPARATUS FOR DETERMINING BEST SHAPE OF COIL FOR USE WITH THE HETERODYNE RECEIVER. LTy FiG. 2.—ROTATING SPARK GaP GIVING APPROXIMATELY 20,000 DiscHARGES PER SECOND. WIRELESS TELEPHONY—FESSENDEN. 179 ance the receiver will obviously not record the higher harmonics. I have experimentally determined that a receiver which restores itself in the ten thousandth part of a second acts with sufficient rapidity. HISTORY OF THE DEVELOPMENT OF WIRELESS TELEPHONY. The writer has been asked on several occasions how the wireless telephone came to be invented. In November, 1899, shortly prior to the delivery of my previous paper, while experimenting with the receiver shown in figure 3 of that paper, I made some experiments with a Wehnelt interrupter for operating the induction coil used for sending. In the receiver mentioned the ring of a short-period Elihu Thom- son oscillating current galvanometer rests on three supports, 1. e., two pivots and a carbon block, and a telephone receiver is in circuit with the carbon block. A storage battery being used in the receiver circuit? it was noticed that when the sending key was kept down at the sending station for a long dash the peculiar wailing sound of the Wehnelt interrupter was reproduced with absolute fidelity in the receiving telephone. It at once suggested itself that by using a source with a frequency above audibility wireless telephony could be accomplished. Professor Kintner, who was at that time assisting me in these experiments and to whose aid their success is very largely due, was kind enough to make the drawings for an interrupter to give 10,000 breaks per second. Mr. Brashear, the celebrated optician, kindly con- sented to make up the apparatus, and it was completed in January or February, 1900. The experimental work was, however, delayed, as the writer was at that time transferring his laboratory from Allegheny, Pennsyl- vania, to Rock Point, Maryland, and it was not until six months later that the stations at that point were completed and a suitable mast was erected for trying the apparatus. The first experiments were made in the fall of 1900 with the above- mentioned apparatus, which was supposed to give 10,000 sparks per second, but which probably gave less. Transmission over a distance of 1 mile was attained, but the character of the speech was not good and it was accompanied by an extremely loud and disagreeable noise, due to the irregularity of the spark. By the end of 1903 fairly satisfactory speech had been obtained by the arc method above referred to, but it was still accompanied by a disagreeable hissing noise. In 1904 and 1905 both the are method and @ Transactions American Institute Electrical Engineers, November 22, 1899. > United States patent No. 7067386, December 15, 1899. 180 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. another method in which the 10,000 cycle alternator above referred to was employed had been developed to such an extent that the appa- ratus could be used practically and sets were advertised and tendered to the United States Government.* The transmission was, however, still not absolutely perfect. By the fall of 1906 the high frequency alternator had been brought to a practical shape and was used for telephoning from Brant Rock to Plymouth, a distance of 11 miles, and to a small fishing schooner, this being the first instance in which wireless telephony was put in practical use. The transmission was perfect and was admitted by telephone experts to be more distinct than that over wire lines, the sound of breathing and the slightest inflections of the voice being reproduced with the utmost fidelity. As it was realized that the use of the wireless telephone would be seriously curtailed unless it could be operated in conjunction with wire lines, telephone relays were invented both for the receiving and transmitting ends, and were found to operate satisfactorily, speech being transmitted over a wire line to the station at Brant Rock, re- transmitted there wirelessly by a telephone relay, received wirelessly at Plymouth, and there relayed out again on another wire line. On December 11, 1906, invitations were issued to a number of scientific men to witness the operation of the wireless transmission In conjunc- tion with the wire lines. A report of these tests appeared in the American Telephone Journal of January 26 and February 2, 1907, the editor being one of the men present. In July, 1907, the range was considerably extended and speech was successfully transmitted between Brant Rock and Jamaica, Long Island, a distance of nearly 200 miles, in daylight and mostly over land,’ the mast at Jamaica being approximately 180 feet high. In 1907 several European experimenters succeeded in transmitting speech wirelessly, using some of the earlier forms of the writer’s arc method, and some months ago the vessels of our Pacific squadron were equipped with wireless telephones, using this are method, by another American company. METHODS AND APPARATUS. Meruops AND APPARATUS FOR PRODUCING THE ELECTROMAGNETIC WAVES. These have been already referred to. Plate 5, figure 2, shows a rotating spark gap giving approximately 20,000 discharges per sec- ond. This was connected to a 5,000-volt source of direct current. 4 TLetter of July 8, 1905; see The Electrician, London, February 22, 1907; also catalogue of 1904 and subsequent. 6“Tong distance wireless telephony,’ The Hlectrician, October 4, 1907. Smithsonian Report, 1908.—Fessenden. PLATE 6 Fic. 1.—APPARATUS FOR OPERATING ELECTRIC ARC IN GAS UNDER PRESSURE AND IN VACUUM, AND THE CRITICAL DISTANCE ARC. Lin Fig. 2.—APPARATUS FOR OPERATING ELECTRIC ARC IN GAS UNDER PRESSURE. Smithsonian Report, 1908.—Fessenders PLATE 7. Fic. 1.—MULTIPLE GAP WITH ROTATING ELECTRODES; BRASS, AMALGAMATED ZINC, AND GRAPHITE USED. Fic. 2.—MULTIPLE ARC GAP WITH ELECTRODES OF DIFFERENT MATERIALS; UPPER TERMINALS WATER COOLED. Smithsonian Report, 1908.—Fessenden. PLATE 8. Fic. 1.—CONDENSER DYNAMO. Filia. 2.—TYPE OF HIGH-FREQUENCY ALTERNATOR. Smithsonian Report, (S008 Seaccindiens PLATE 9. Fic. 1.—Fl—ELD Disk, 12 INCHES IN DIAMETER, 300 SLoTs. inten al ih ee cae at : ni Fic. 2.—ARMATURE AND FIELD CoiLs, 600 SLoTs. WIRELESS TELEPHON Y—FESSENDEN. 181 The terminals are of 40 per cent platinum-iridium. In operation the apparatus is arranged to charge a condenser to a definite potential and discharge it. Plate 6 shows forms of apparatus for operating the arc in a gas under pressure. The apparatus of figure 1 on plate 6 is also used for the are in vacuum and the critical distance are. Plate 7, figure 1, shows a multiple gap with rotating electrodes, brass, amalgamated zinc, and graphite being used. Plate 7, figure 2, shows a multiple are gap with electrodes of dif- ferent materials, the upper terminals being water cooled. Plate 8, figure 1, shows a condenser dynamo. Plate 8, figure 2, shows a general view of one type of high-fre- quency alternator. It is driven by a motor and a De Laval gear. It has been operated at 96,000 cycles per second, but is generally run at 81,700. Plate 9, figure 1, shows a field disk; it is 12 inches in diameter and there are 300 slots on it. Plate 9, figure 2, shows the armature and field coils. There are 600 armature slots, each containing two turns of 13 mil wire. The field current is 5 amperes. The resistance of the armature is 6 ohms; it gives 160 volts and about 7 or 8 amperes. Other armatures have been constructed having a resistance of 4 ohms. For some work double armatures are used giving about 270 volts. The output of the single-armature machines at 81,700 cycles is approximately 1 kilowatt. The output of the double-armature machine is approxi- mately 2 kilowatts. Other types of high-frequency alternators are under construction. One type shown in plate 10, figure 1, is designed for use on ship- board. The armature disk is 6 inches in diameter and two armatures are used. It is arranged to be mounted on gimbals and to be driven by a steam turbine connected to the steam pipe by flexible, armored steam hose. The frequency is about 100,000 and the output about 3 kilowatts, Another type, which is at present being constructed by Mr. Alex- anderson, to whose efforts the success of this type of generator is largely due, is designed to have an output of 10 kilowatts. Designs have been made for a generator of still larger size, with a calculated output of 50 kilowatts and a frequency of 50,000. This machine is intended for trans-Atlantic work. For some of these machines, instead of driving by gear or steam turbine, a special 2-cycle motor has been devised, to operate at a frequency of 500 cycles per second. The high frequency alternator method 1s believed to possess a num- ber of advantages over other methods, inasmuch as it is set in opera- 182 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. tion by merely opening a steam valve and has no complicated elec- trical apparatus or circuits of any kind. The speed is regulated by the steam pressure, this being accomplished by an electrically operated reducing valve. For measuring the frequency various speed indicators have been tried, but it has been found that the best way is to use a resonant circuit, with an ammeter (shown in plate 11) in it,’ this being an ex- tremely sensitive means of indicating the frequency, and in addition affording a means of automatically keeping the speed constant to a small fraction of a per cent. The reducing valve is adjusted so that if left to itself the machine will run slightly above speed.” As soon as it reaches one-tenth of 1 per cent higher than its designed speed, the resonance begins to fall, and a contact is opened which shghtly throttles the steam. In this way the frequency is kept varying be- tween the limits of one-tenth of 1 per cent above speed and one- tenth of 1 per cent below speed. Where the drive is electric instead of by turbine, a storage battery is used to drive the two-phase gen- erator, and even better results may be obtained as regards regulation than with steam. TRANSMITTERS. The types of transmitters most commonly used are the carbon transmitter and static transmitter, and the carbon transmitter relay. Plate 10, figure 2, shows the standard type of carbon transmitter. It was found that the ordinary carbon transmitter was unsuited for wireless telephonic work, on account of its inability to handle large amounts of power. A new type of transmitter was therefore designed, which the writer has called the “ trough” transmitter. It consists of a soapstone annulus to which are clamped two plates with platinum-iridium electrodes. Through a hole in the center of one plate passes a rod, attached at one end to a diaphragm and at the other to a platinum-iridium spade. The two outside electrodes are water jacketed. This transmitter requires no adjusting. All that is necessary is to place a teaspoonful of carbon granules in the central space. It is able to carry as much as 15 amperes continuously without the articu- lation falling off appreciably. It has the advantage that it never packs. The reason for this appears to be that when the carbon on one side heats and expands the electrode is pushed over against the carbon on the other side. These transmitters have handled amounts of energy up to one-half horsepower, and under these circumstances give remarkably clear and perfect articulation and may be left in “ Electrical World and Engineer, November 11, 1899. > Since writing the above, my attention has been called to the fact that the general method of governing by resonance was invented and patented by Kemp- ster B, Miller, United States patent No. 559187, February 25, 1896. Smithsonian Report, 1908.—Fessenden. PLATE 10. Fic. 1.—TYPE OF HIGH-FREQUENCY ALTERNATOR FOR USE ON SHIPBOARD. Fila. 2.—STANDARD TYPE OF CARBON TRANSMITTER. Smithsonian Report, 1908.—Fessenden. ~ PLS 4. AMMETER FOR INDICATING FREQUENCY AND AUTOMATICALLY REGULATING SPEED. Smithsonian Report, 1908.—Fessenden. PLATE 12. FiG. 2.—TRANSMITTING RELAY FOR STRONG CURRENTS. Smithsonian Report, 1908.—Fessenden. PLATE 13 FAULTY TYPE OF CONDENSER TRANSMITTER. WIRELESS TELEPHON Y—FESSENDEN. 1838 circuit for hours at atime. Plate 12, figure 1, shows a modified form with spht back. Plate 12, figure 2, shows a transmitting relay for strong currents. The only thing noticeable about this is that the telephone magnet is a differential one. Plate 13 shows a type of condenser transmitter in which the vibra- tion of the diaphragm alters the electrical capacity of the transmitter, thus throwing the circuit in and out of tune or spilling more or less energy through a leakage circuit. Plate 14, figure 1, shows another type of transmitting relay for amplifying very feeble currents. It will readily be understood that where a person in Albany, for example, wishes to talk to another person on board a ship off New York, the wireless station being located near New York, the volume of the transmission received at New York will not be very strong, and while it may be possible to transmit it without amplification, amplification is advisable. This receiver is a combination of the differential magnetic relay and the trough transmitter. An amplification of fifteen times can be obtained without loss of distinctness. The side electrodes of the trough are water jacketed. The successful amplification depends upon the use of strong forces and upon keeping the moment of inertia of the moving parts as small as possible. Amplification may also be obtained by mechanical means, but as a rule this method introduces scratching noises, which are very objectionable, even though comparatively faint. Other types of transmitters have also been used, such as liquid jet transmitters, transmitters operating by closing the air gap in a mag- netic circuit (plate 15, figure 1), and so changing the inductance of the oscillating circuit, etc. Plate 14, figure 2, shows a loud-speaking telephone receiver. A small iron disk is placed opposite a nozzle through which air at high pressure is blown. As is well known, this causes the disk to be held close to the nozzle. The telephone magnets alter the position of the disk and thus produce very loud talking. The transmitting relays are connected in the wire-line circuit in the same way as the regular telephone relay, except that in place of being inserted in the middle of the line they are placed in the wireless station and an artificial line is used for balancing. There is no diffi- culty met with on the wireless side of the apparatus, but on the wire- line side there are the well-known difficulties due to unbalancing which have not yet been entirely overcome. For the correction of these difficulties, therefore, we must look to the engineers of the wire telephone companies. At present the difficulties are, if anything, less than those met with in relaying on wire lines alone. 88292—sm 1908——13 184 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. TRANSMITTING CIRCUITS. Figure 2¢ shows a type of are circuit. Figure 3” shows a suitable type of connection for use with a high- frequency alternator. Figure 4° shows a type of circuit for use with the condenser transmitter. Figure 5° shows a type of circuit in which the modulation is accomplshed by changing the induc- tance of one of the oscillating circuits. Fic. 2.—Type of are circuit. As a matter of fact the transmitter may be placed almost anywhere in the circuit between the arc or dynamo and the antenna, or between the arc or dynamo and ground, or in the transformer circuit, or in shunt to an inductance or capacity, the results obtained in all cases being indistinguishable. The sole criterion of success seems to be that the trans- mitter should be capable of handling the energy and the circuit should be properly adjusted. Some success has also been attained by placing the transmitter in the field of the dynamo,’ but this method requires very care- ful designing of the field circuit. Receivers —The receiver which the writer has found most satisfactory for general purposes is the liquid barretter. Plate 15, figure 2, and plate 16, figure 1, show this receiver. It consists of a fine platinum wire, about a ten-thousandth of an inch in diameter, immersed in nitric acid. Tests made with this receiver show that it responds without apparent loss of efficiency to notes as high as 5,000 per second. Some very careful meas- urements recently made by my assistants, Messrs. Glaubitz and Stein, give the following results: Vey Fig. 3.—Type of connec- tion with high-fre- + quency al- ternator. Voltage of high frequency circuit necessary to produce readable signals, 15. 10-* volts. 4 United States patents Nos. 706742, June 6, 1902, and 730753, April 9, 1908. b United States patent No. 706742, June 6, 1902. ¢ United States patent No. 706747, September 28, 1901. 4 United States patent No. 793649, March 30, 1905. Smithsonian Report, 1908.—Fessenden. PLATE 14. Fic. 1.—TYPE OF TRANSMITTING RELAY FOR AMPLIFYING VERY FEEBLE CURRENTS. Fic. 2.—LOUD-SPEAKING TELEPHONE RECEIVER. Smithsonian Report, 1908.—Fessenden. PLATE 15. Fic. 1.—TYPE OF TRANSMITTER OPERATING BY CLOSING AIR GAP IN MAGNETIC CIRCUIT. Fic. 2.—LiquiD BARRETTER RECEIVER. WIRELESS TELEPHON Y—FESSENDEN. 185 Ohmic resistance of receiver, 2,500 ohms. Value of high frequency current necessary to produce readable signals, 6 & 10-° amperes. Electromagnetic wave energy required to produce audible note for period of one second, 1 X 10~ ergs. The telephone used for detecting the signals had a resistance of approximately 1,000 ohms. Some measurements were made to determine the change of current in the telephone circuit by using a sensitive galvometer in series with the telephone, but the results obtained were obviously too low, possibly on account of the electrostatic capacity of the turns of the galvanometer with respect to each other. It will be noted that the amount of electromagnetic wave energy necessary fie. 4.—Cireuit for to produce a signal is considerably less than that use with condenser : : : : 5 : transmitter. given in a previous note. The difference is possi- bly to be attributed to improvements in adjustment and operation. The above measurements were taken by shunting the barretter across a piece of straight resistance wire in series with a hot-wire ammeter, to determine the voltage necessary, and by introducing resistance in series with the barretter to de- termine the resistance of the barretter. The figures were also checked in a number of other ways and very concordant results were obtained, so that it is believed they may be relied upon. The previously mentioned thermoelectric receivers or rectifiers of Doctor Austin and Mr. Pickard, shown in plate 16, figure 2, and the vacuum tube receivers of Fleming, De Forest, and Cooper-Hewitt also act very satis- factorily. The fact that the writer has not been able to get as good results from them may be due to greater familiarity with the ere | ok ner liquid barretter and heterodyne receiver. pecomi enedneketatete Plate 17, figures 1, 2, and 3 show forms of ieee ok iia ae heterodyne receiver adapted for use for telephonic work. Receiver connections—Where the wireless telephone is operated by first talking into the transmitter and then throwing a switch and listening, the usual wireless telegraphic connections are used. This has been found in practice to be very inconvenient, however, and @ Hlectrical World and Engineer, October 31, 1905. 186 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. several methods have therefore been devised for talking and listening simultaneously, which methods can, of course, also be applied to du- plex wireless telegraphy. Among these methods may be mentioned the commutator method @ and the balance method.? The former method is fairly well known and consists in rapidly connecting alternately the transmitter and receiver. The balance method consists in using a phantom aerial as shown in figure 6, where P is a phantom aerial, the circuit having such capacity in- ductance and resistance as to balance the radiating antenna. The apparatus 1s shown in plate 18, figure 1. Fic. 6.—Balance method with phantom aerial P. In order entirely to cut out disturbances in the receiver while sending, an interference preventer, I P, the elements of which are shown in plate 18, figure 2 and plate 19, figure 1, is used in the receiv- ing circuit. It may be here mentioned that balance methods work much better with wireless telephony and telegraphy than with line telephony and telegraphy, for the reason that the radiation resistance of an antenna is absolutely definite and is not affected by the weather, as are line circuits. Consequently, the balance can be made very sharp and 2 United States application, No. 350199, December 31, 1906. ¢ United States application, No. 866528, April 5, 1907. Smithsonian Report, 1908.—Fessenden. PLATE 16. Fic. 1.—LIQUID BARRETTER RECEIVER. Fic. 2.—THERMOELECTRIC RECEIVERS OR RECTIFIERS. Smithsonian Report, 1908.—Fessenden. PLATE 17. Fia. 1. FiGwe: Fig. 3. FORM OF HETERODYNE RECEIVER ADAPTED FOR USE IN TELEPHONE WORK. Smithsonian Report, 1908.—Fessenden. PLATE 18. Fic. 1.—APPARATUS FOR BALANCE METHOD OF TALKING AND LISTENING SIMULTANEOUSLY. Fic. 2.—PART OF INTERFERENCE PREVENTER TO ELIMINATE DISTURBANCES IN RECEIVER. Smithsonian Report, 1908.—-Fessenden: PLATE 19 Fic. 1.—PART OF INTERFERENCE PREVENTER TO ELIMINATE DISTURBANCES IN RECEIVER. Fig. 3.—TALKING BY RELAYS FROM A LOCAL CIRCUIT. WIRELESS TELEPHON Y—FESSENDEN. 187 once made does not need to be altered.* Of course, half the energy is lost, but this is a matter of practically no importance, as the cutting down of the strength of a telephonic conversation to one-half is as a rule hardly noticeable, especially where there are no line noises or distortion of the speech through capacity effects. Receiving station relay—tThe receiving station relay is similar to the transmitting relay shown in plate 14, figure 1. The same remarks apply to its use in connection with wire lines as to the transmitting relay. OPERATION. As will be realized from the above, the operation of a wireless tele- phone system is very simple. The operator merely throws his switch to the position for telephoning and talks into an ordinary transmitter and listens in an ordinary telephone receiver. When the duplex method is used, as is always advisable, the conversation proceeds exactly as over an ordinary telephone line. Plate 20 shows a phono- graph transmitting music and speech wirelessly. Plate 19, figure 3, shows talking by relays from a local circuit. I believe I am correct in saying that the transmission by wireless telephone is considerably more distinct than by wire line and that the fine inflections of the voice are brought out much better. This, I presume, is due to the fact that there is no electrostatic capacity to distort the speech, as in the case of wire lines, though I think the effect is also partly due to the absence of telephone induction coils with iron cores. Possibly some of the gentlemen present have wit- nessed the operation of the wireless telephone transmission between Brant Rock and Plymouth and between Brant Rock and Brooklyn. If so, I think they will bear me out in saying that the transmission was clearer than over wire lines. As a rule, there is absolute silence in the wireless telephone receiver except when talking is going on, though of course the usual noises “This method may, of course, be used for duplex working in wireless teleg- raphy. As some question has been raised in regard to the capacity of wire- less telegraph lines the writer would say that he has received messages at the rate of 250 words per minute by wireless and is now experimenting with apparatus designed to give 500 words per minute. With duplexing this gives 1,000 words per minute or 60,000 words per hour. The manager of one of the largest cable companies has stated (London Daily Mail, September 24, 1907) that all the trans-Atlantic cables together send 24,000 words per hour. It would appear, therefore, that if capacity alone be considered a single station on each side of the Atlantic can handle more traffic than all the present cables. It should be pointed out, however, that the mere ability to handle the messages is not sufficient and that unless the wireless telegraph companies obtain land facilities equal to those at present enjoyed by the cable companies they can not handle the traffic as efficiently, i. e., can not deliver a message from New York to an individual in London and receive a reply in the same time. Plate 19, figure 2, shows a Wheatstone transmitter used for the test referred to. 188 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. may be heard if persons are walking across the room, ete. This makes listening less of a strain than when talking over wire line. Even during severe atmospheric disturbances the talking is not inter- fered with to any noticeable extent, provided, of course, that an inter- ference preventer is used. A comparative test was made with talking between Brant Rock and Brooklyn by wireless and by wire telephony. The talking over the wire line was done from a long-distance station in Brooklyn. The wireless transmission was considerably the better. The fact that the wire line included in its circuits a cable from New York to Brook- lyn was of course a disadvantage, but even allowing for this, prac- tice and theory appear to be in agreement to the effect that transmis- sion by wireless telephony over long distances is better than by wire line. This method should be of especial value to independent telephone companies, which have their local exchanges, but no long-distance lines, especially since no franchises or rights of way are necessary. POSSIBILITIES. LocaL ExcHANGES. There is no immediate prospect that wireless telephony will take the place of local exchanges. The difficulty in regard to the number of tunes can be overcome, but the fact remains that high frequency oscillations can not be transmitted over wire, and hence each sub- scriber must have his own generating station. At the present time no method is known which would be practical if placed in the hands of a subscriber. If such means should be found it would be very con- venient to call up directly instead of through an exchange, but as I see it there are no immediate prospects of this. LONG-DISTANCE LINES. I believe, however, that there is a field for wireless telephony for long-distance lines. The present long-distance lines are very expen- sive to construct and maintain, and a storm extending over any considerable section of country inflicts considerable loss on the tele- phone companies. Moreover, the distance of transmission is limited by the electrostatic capacity of the line, as I understand it. Wire- less telephony would have the following advantages: 1. The initial cost would be very much less than that of wire lines. 2. The maintenance would be practically negligible in comparison. 3. In case of any breakdown it would be right in the station and not at some unknown point outside on the line. 4. The depreciation would be comparatively small. 5. The number of employees required would be smaller. “AISSSATSYIM HOS3SdS GNV OISNIA) ONILLINSNVY | HdVYSONOHd "O06 ALV1d ‘uapuassej—'gQ6} ‘Hodey urluosy}iWws Sets WIRELESS TELEPHON Y—FESSENDEN. 189 6. The transmission is better, and as there is no distortion of the speech the working distance is, it is believed, considerably greater. 7. The flexibility is greater. With wire lines a telephone company may not be able to give a Boston subscriber a line to New York, while having lines from Boston to Chicago and from Chicago to New York free. Operating wirelesly the wireless circuit normally used for operating between New York and Chicago and between Boston and Chicago could be used to operate from Boston to New York. 8. No right of way need be purchased, and franchises, it is believed, are not necessary. It will be noted that I have not mentioned any disadvantages of wireless telephony for long-distance work. I presume this is because I am not a telephone engineer. I hope the defects will be discussed by the experts who are familiar with telephone operation and there- fore better able to point them out. Before leaving this part of the subject I would say that I think the question of interference has been worked out to such an extent that no serious difficulty need be feared in that direction. TRANSMARINE TRANSMISSION. Wireless telephony is peculiarly suited for this class of work. Pupin’s ingenious and beautiful method has been successful at Lake Constance, Switzerland, I believe, but even assuming that deep-sea cables of this type could be laid and operated successfully, they would nevertheless be very much more expensive than wireless telephone stations. It is believed that wireless telephony will come into ex- tended use for this purpose. Even without further development telephonic communication could be established between Norway or Denmark or Germany or Spain and Great Britain; between Sar- dinia and, Corsica and France and Italy; between France and AI- geria; between Australia and Tasmania and New Zealand; between the United States and Cuba and Porto Rico, ete., were it not that it is at present forbidden by law. As regards telephonic communication between England and Amer- ica, My measurements show that this should be possible with an expenditure of approximately 10 kilowatts and suitably large towers, say 600 feet high, or with some of the new forms of antenna. Whether such a transmission would be commercially valuable or not is another matter. Personally I do not see that it would, but when I remember that at the time when the telephone was first being intro- duced a number of eminent business men decided that the house-to- house printing telegraph would be more of a success commercially than the telephone, for the reason that no one would want to do business unless he were able to have a record of the transaction, I must admit that there is a possibility of my being mistaken in this. 190 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. WIRELESS TELEPHONY FROM SHIP TO SHIP. Here, of course, wireless telephony occupies a unique position. Wireless telegraphy has the disadvantage that a telegraph operator must be carried. The additional expense is an objection in many cases. The proposition that the captain or mate should also be a tele- graph operator has not met with favor. Anybody, however, can operate the wireless telephone and almost every vessel carries an engineer capable of repairing the electrical apparatus in case of acci- dent. The final arrangement will, I believe, be this; that passenger vessels will carry a telegraph operator and use the telephoning appa- ratus for ordinary work and for telegraphing where it is desired to communicate over long distances. Other vessels will use the tele- phone alone. Wiretess TELEPHONS FROM Sup ro LocaL ExcHANnGE. This also will, I think, have considerable value, as enabling the captain of a vessel to communicate, by relaying over the wire line, with the owner of the ship, or enabling a passenger on a vessel to communicate with friends on shore. RANGE OF WIRELESS TELEPHONY. ATMOSPHERIC ABSORPTION. The great obstacle to long distance wireless telegraphy and te- lephony is atmospheric absorption. For short distances up to 100 miles in the Temperate Zone there is little difference between the strength of the signals at one time of the day and another. As soon as the distance is increased much over 100 miles for the Temperate Zones and 40 or 50 miles for the Tropics the signals at night are very irregular and there is great absorption during the daytime. The daylight absorption may be so great that less than a tenth of one per cent of the energy transmitted gets through. Some nights will be as bad as daytime, while on other nights there will be apparently no absorption. Figure 7 is a curve showing the strength of the messages trans- mitted between Brant Rock, Massachusetts, and Machrihanish, Scot- land, at night, during January, 1906. Nothing at all was received that month during daytime. The change in the strength of the signals is very sudden. In working from Brant Rock to Porto Rico, a distance of 1,700 miles, the strength of the signals with short wave lengths would fall off to one one-thousandth of their former value during a period of less than fifteen minutes, while the sun was rising. Early experiments showed that the absorption was greater as the wave length was increased and the effect was at first attributed to absorption in the neighborhood of the sending station, and was WIRELESS TELEPHON Y—FESSENDEN. 191 thought to increase continuously with the wave length. This fluc- tuating absorption at one time appeared to place a fundamental obstacle to commercial wireless telegraphy, as telegraph engineers will easily appreciate the impossibility of operating telegraph sys- tems with circuits where the strength of the received signals may fall to one thousandth of its value or rise to a thousand times its value in the course of a few minutes. INTENSITY OF SIGNALS, UNITY IS JUST AUDIBLE MESSAGES, DAY OF MONTH Fic. 7.—Curve showing variation of intensity of transatlantic messages for the month of January, 1906. It was therefore considered absolutely essential, in order to decide whether long-distance wireless telegraphy was commercially possible or not, to investigate this phenomenon fully. As a preliminary, the station at Brant Rock sent signals to four or five other stations at varying distances and comparative readings were taken. The follow- ing table shows the general character of the results obtained : Strength of signals Station. Distance. received on worst nights.@ WOMPANVZSICOUAL Cc sagan cic new sereoeceat a aciein cme Namen Tce ese weelicles Sean's 200 yards ..... 1, 000 SRE MRT a pe ee letter af fasat cea o so ota asats wie sista a Se inl wigs TK 3 Sia Dine ws Sle wisla we wSfeialeroe SOEs tea 1, 000 SIG DEMETRI 5 cegcocode bab Scoadaodde ne SS crop aosb ecto sco AoA eS Saesedeuraccusoe 170 miles ..... 500 PAPURO PIP Maes Sodan che see esas ces on assnsineseste sone scan ces wedwoooeecees 270 miles ..... 300 \ VIG LOO SI Oy Os eS AS ea I Se i eI Salaae ena’ aa shee acc aas,aje:= ae 400 miles ..... 150 HUB KN Wa ENDS ons Sn soomenencdsese se eeeesee cedar centmonescusesseueescercae 3,000 miles... 1 * Strength of unabsorbed signals taken as 1,000. _ These experiments proved conclusively that the absorption did not take place in the neighborhood of the sending station, because @ A mathematical explanation of this supposed fact was given by Doctor Fleming, Principles of Electric Waves Telegraphy, pp. 617-618, 1906, the follow- ing conclusions being reached: “ Accordingly, the chief part of the weakening of the wave by sunlight is done in the neighborhood of the sending antenna, where the magnetic force H is greatest, and it is more sensible for long and powerful waves than for short and feeble ones. This agrees with the observations of Mr. Marconi.” 192 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the strength of the signals received at near-by stations was the same during the day as during the night, while there was great variation in the strength of signals received at stations farther away. It was also found that the absorption at a given instant was a func- tion of the direction as well as of the distance, since on a given night the signals received by stations in one direction would be greatly weakened, while there would be less weakening of the signals received by stations lying in another direction, while a few hours or a few minutes later the reverse would be the case. This was thought to be connected with the coming weather condi- tions, but before this fact is proved a much larger amount of data must be collected. Through the kindness of the United States Weather Bureau I was enabled to obtain a chart of the magnetic variations, and on comparison of these with the absorption between the Massachusetts and Scotland stations there appeared to be a quite definite relation, 1. e., the greater the absorption the greater the mag- netic variation. Here also, however, much more data is needed before arriving at a definite conclusion. The fact that the absorption did not take place in the neighborhood of the sending station having thus been definitely settled the next point to be investigated was whether or not there was any way of overcoming it. The fact that variations in the absorption occurred with extreme rapidity, the absorption increasing sometimes a hundred fold in a single minute, and at night, when the effect could not be due to the sun directly, seemed to indicate that the body producing the absorp- tion, whatever it was, was not in a state of continuity, but was broken up into masses lke clouds.¢. This also was in accordance with some experiments made in Brazil in 1905. Irom optical theories it is known that where the absorption is produced by conducting masses of a more or less definite size the absorption is to a certain extent selective. The next point in the investigation was, therefore, to determine whether there was any possibility of this being the fact in the case of the absorption of wireless signals. Comparative tests were therefore made of the absorption at night and during the day between Brant Rock and Washington, with wave lengths varying from a fraction of a mile up to four or five miles. It was found that the absorption did not increase continuously with the wave length, but reached a maximum and then fell off with great suddenness. Figure 8 shows the general character of the curve, the ordinates referring to the amount of the absorption and the abscissas to the wave frequency. 4 Wlectrical Review, May 18, 1906. WIRELESS TELEPHON Y—FESSENDEN. 193 It may be noted that the absorption is a maximum at a frequency of about 200,000 per second, nine hundred and ninety-nine thou- sandths (0.999) of the energy being absorbed at this frequency dur- ing daylight, while for a frequency of 50,000 the absorption does not appear to be appreciable. Longer experiments, of course, might show some absorption, but in any case it is of a different order from the absorption for the shorter wave lengths. Experiments were then made between Brant Rock and the West Indies, a distance of 1,700 miles, during the spring and summer of 1907. It was found that the results were of the same character, i. e., that while there was greater absorption for frequencies of 200,000 there was comparatively little absorption for frequencies in the neighborhood of 80,000, and messages were successfully transmitted in daylight with this latter frequency. No messages were received in daylight with the higher frequency, though messages transmitted from the same station and with the same power and frequency were 100% ABSORPTION 200,000 100,000 FREQUENCY Fic. 8.—Absorption curve, tests between Brant Rock and Washington. officially reported as having been received at Alexandria, Egypt, a distance of approximately 4,000 miles. The fact that these experiments were made during summer weather, and the receiving station was in the Tropics, and the fact that the distance, 1,700 miles, was practically the-same as that between Ire- land and Newfoundland, definitely settled the question as to whether long-distance wireless telegraphy was a commercial possibility or not, and the results were therefore published.* Since the publication of the above results, transmission has pea accomplished by means of these long waves over still greater dis- tances during daylight. Mr. Marconi, early in October, 1907, aban- doned the short-wave lengths previously used and adopted one over two units in length, and immediately succeeded in operating between @The Electrician (London), July 26, 1907. 194 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Glace Bay, Nova Scotia, and Clifden, Ireland, a distance of more than 2,000 miles, the frequency being approximately 70,000. The same messages were received at Brant Rock, Massachusetts, a distance of nearly 3,000 miles. Still more recently Captain Hogg, of the “ Glacier,” has written that during the southward passage of the Pacific fleet he received messages from the station at Brant Rock, Massachusetts, while off Cape Ste. Roque, Brazil, South America. The frequency used for sending was approximately 80,000, and the messages were received with the very interesting and sensitive silicon receiver invented by Mr. Pickard. This distance of 3,000 miles is the greatest yet achieved by wireless transmission during daylight, and would indicate that with the use of suitable high towers much longer distances can be reached. RANGE OF WIRELESS TELEPHONY AND WIRELESS TELEGRAPHY COMPARED. For the same power it is possible to telegraph to a farther distance than to telephone. Distinct speech depends upon the presence of harmonics of a frequency as high as 1,200 per second. The amplitude of these harmonics is, according to some rough experiments made by the writer, only about 1 per cent of the fundamental frequency. Consequently, with a perfectly modulated transmitter, one hundred times as much energy would be necessary to telephone a given distance as to telegraph. It fortunately happens, however, that a carbon transmitter and also the circuits in which it is used, can be so con- structed as not to modulate perfectly, but can be arranged so as to accent the higher harmonics. With transmitters arranged for the purpose good transmission has been obtained with thirty times the energy required to produce audi- ble telegraphic signals. By still further modification the power re- quired has been reduced to approximately ten times that necessary for telegraphing, curiously enough without noticeably distorting the character of the speech. There is one fact, however, which prevents the ratio from being as large practically as the instruments show, i. e., speech can be satisfactorily understood with a less increase of power above a minimum audibility than telegraphic signals. The amount of power necessary for wireless telephony may there- fore be taken as approximately five to fifteen times that necessary for wireless telegraphy, i. e., under the same circumstances and for the same power the wireless telegraph will carry two to four times as far. The difference in range would be very much greater also but for the curious fact that there is much less falling off with sustained oscillations than with intermittent groups of waves, even though the frequencies are identical. WIRELESS TELEPHON Y—FESSENDEN. 195 This fact has been repeatedly determined by sending between Brant Rock and Brooklyn on the same frequency, using in the one case spark-produced trains of waves and in the other the high-frequency dynamo. The difference in the falling off for the same frequency and energy is very great, but further work is necessary before any- thing very definite can be said about it or the reasons finally deter- muned. \* +" | Mr. Fessenden concludes his article with a discussion of the diffi- culty of securing governmental authority and legislation for the development and operation of ‘wireless telegraph systems by private corporations. | PHOTOTELEGRAPHY.¢ By HENRI ARMAGNAT, Consulting engineer, expert for the Tribunal Civil de la Seine. The transmission of pictures to a distance by the electrical current is not a new idea. It had its inception perhaps some thirty years ago when electricity itself was developing, and even then furnished ground for hopes which are to-day partially realized. The inven- tion of the photophone by Graham Bell had made generally known the sensitiveness to ight of selenium, and its utilization for the trans- mission of pictures was at once proposed by many. ‘These attempts were unsuccessful. Indeed, during the last thirty years no further advance has been made in the direct reproduction at a distance of the images of real animate objects. But if we restrict our problem to requiring electricity to send and reproduce, point by point, an inanimate picture, we shall find several interesting solutions, some of which have had practical trials and require but little further development to be commercially practicable whenever a demand for phototelegraphy grows. The transmission of pictures containing only blacks and whites without any half-tones was tried in 1851 by Backwell, in 1855 by Caselli, and finally by d’Arlincourt in 1872. All these inventors had in view not the sending of a picture, but the transmission of writing. Their purpose was to send autographs by means of the telegraph, but they naturally could have reproduced equally well other pen designs. As the phototelegraphy of to-day still embodies these early ideas, it is really no innovation. In order to reproduce in B an image, A (fig. 1), it suffices to move over A a style, a, so that it follows successively a series of very close parallel lines, while by some suitable means a second style, 0, follows upon the receiver, B, traces similar to those upon A, occupying at each instant a position upon B similar to that which a has upon A. “Translated, by permission, from the Revue Scientifique, April 18, 1908; fifth series, Vol. IX, No. 16, Paris, 1908. 197 198 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. The two styles thus work synchronously. If now we so devise our apparatus that when a@ reaches a black portion of its image, the style, 6, marks upon B a black trace, then, when sufficient time has elapsed for the style to have run over the entire image, we will have in B a reproduction of A, except that the latter will consist of a series of points and parallel traces, and so will not have the con- tinuity of the original image. The ever-increasing use of the processes of photo-engraving has accustomed us to such discontinuities and, provided the parallel traces are not too far apart, experience has shown that the reproduction will be very satisfactory. Let us consider the methods used to produce the synchronism. The phototelegraphic apparatus for which the processes have been the most developed in this respect make use of an early conception used by d’Arlincourt and which has now been carried to a very high point of precision in certain actual telegraphs such as that of Baudot. The device used is as follows: The sheets, A and B, are roiled upon rotating cylinders. The cylin- der of the receiver, B, turns a little faster than that of A, but the advance made each turn is too small to produce a sensible distortion of the image. In order to perfect B the synchronism, it is sufficient to stop the cylinder, B, a very short time until the cylinder, A, turns to the corresponding position. At that moment a contact, controlled by A, sends through the line con- necting the two stations a current, freeing B, and the two cylinders start simultaneously from the corresponding parts at each turn. This device avoids the accumulation of small errors in the speeds of the two cylinders, and the resulting image is practically satisfactory. The speed of rotation of B is so adjusted as to be a half or one per cent faster than that of A and the moment of correction is so chosen that it always falls somewhere on the margin of the paper where no part of the picture is to fall. The styles marking on the cylinders would always trace the same circumference if they were not made to advance gradually toward one side. This movement is impressed by means of a screw parallel to and whose motion is controlled by the cylinder. A nut mounted on the screw carries the style and as this nut is kept from turning, the style must advance. The combination of these two movements, the rotation of the cylinder and the advance of the style, causes this style to explore successively all points of the picture. Fie. 1, PHOTOTELEGRAPHY—ARMAGNAT. 199 So much for the past. Let us now see how the modern inventor has solved the many other difficulties. Professor Korn, of Munich, alone makes use of selenium; all the others use some mechanical device. KORN’S APPARATUS. This apparatus is represented in figure 2, in the form in which it was tested in Paris, by the journal “ l’Ilustration,” in February, 1907. Since then the scheme has been altered as shown in figure 5, but this modification, interesting in practice, really offers no real change in the mode of operation, so we will use figure 2 for describing this process. At the transmitting station, the picture to be reproduced is in the form of a photographic film rolled upon the cylinder of glass, a. This cylinder is run by an electric motor through the tangent screw and wheel seen at the upper part. The farther metallic end of the cylinder forms a nut working on a vertical axis so that as the cylin- der turns it mounts or de- scends. Under the cylinder is | | placed the essen- [-==4 a] ill tial organ of the : transmitter, the selenium cell. A source of light, b, placed at the side, sends a bundle of rays upon the lens, c, which focuses them upon a point of the photographic film; these rays traversing the picture are more or less weakened according to the opacity of the film at that point; the transmitted light diverges and is received by a prism, d, which reflects them to the selenium cell, e. It is easily seen that, because of the motion of rotation and the progression of the cylinder, all points of the picture pass successively under the concentrated pencil of light, and the selenium cell is con- tinuously acted upon by the successive variations in the intensity of the light. Selenium, when it is in the suitable allotropic state, offers a much greater resistance to the passage of an electric current when in the dark than when exposed to the light or heat. Consequently, if the selenium cell is placed in a telegraph line with a battery, the strength of the current received at the other station will show at each instant the opacity of the point of the image then passing under the pencil of rays, and it remains only to utilize the variation of this cur- 88292—sm 190S——14 Fic. 2.—IKorn’s apparatus. 200 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. rent for reproducing at the receiving station the image at the sending station. We will not describe here the device used by Korn for making manifest this image. He used the cathode rays produced by currents of high frequency and a very sensitive galvanometer. This very ingen- lous receiving device was, however, too delicate for ordinary practice and is to-day replaced by a much simpler and rougher apparatus. The current sent by the transmitter passes through a_ string- galvanometer, which is made to more or less obscure a window, ™, through which a luminous pencil of rays, emanating from the lamp, k, and concentrated by the lens, 7, enters the dark chamber which holds the receiving cylinder, 7. The latter turns upon its axis simi- larly to the transmitting cylinder and is covered with a sensitive photographic film. The lamp, %, and the lens, 7, are so placed as to produce upon this film a very minute point of light; the varying diaphragm carried by the string- galvanometer renders the intensity of this point of ight proportional, or inversely proportional, to the current coming over the lne, and consequently to the opacity or transparency of the corresponding point of the image we wish to reproduce. The impression upon the film varies with regard to the original image according to the mode of disposition of the dia- phragm so that it is possible to obtain a positive or negative reproduction. It remains only to de- velop the film to have the complete reproduction of the image sent over the line. Figure 2 indicates the device used for the synchronism: The lever, u, passes very close to the disk, 7, and stops that disk when ~ hits the spur, z; as the movement from the electric motor is transmitted to the cylinder through a friction clutch formed by the cone, 2, and the box, 7, the motor continues to turn; as soon as the transmitting cyl- inder, a, comes to the proper point, the finger, 7, will touch the spring, g, breaking the current which traverses the electro-magnet, 7; the latter frees its armature, the lever, 7, comes away from 7, freeing the cylinder which then resumes its rotation. The same course of events recurs at each turn of the cylinder, correcting the small variations in its speed, provided only that the receiving cylinder, j, turns a little faster than the transmitter, a. Let us examine some further details of the apparatus. The seleni- um cell is formed of a little slab of stone or slate, figure 3, upon which Hic. 3.—Selenium cell. PHOTOTELEGRAPHY—ARMAGNAT. 201 are wound, parallel and insulated from each other, two fine platinum wires, | and 2. Upon one face this slab is covered with a very thin coat of selenium so that these two platinum wires are now connected through the selenium and this separating resistance can be doubled or even more than doubled by removing the cell from the light to dark- ness. It is also extremely important to protect these cells from the ordinary variations of temperature during an experiment as their resistance varies from both light and heat. The string-galvanometer used by Korn is a very recent device and was first made a few years ago by Ader as a receiver for submarine telegraphy. It possesses a very great sensibility and Einthoven has since constructed one which will detect currents of the order of 10-12 amperes—a millionth of a microampere. Reduced to its simplest, schematic form, the a string-galvanometer consists of a thin conduct- ing thread, f (fig. 4), stretched between two fixed points, a and 0, and passing between the poles, PP, of an electro or a permanent magnet. A current passing through this thread causes it to bend in a direction perpendicular to the lines of force of the field and this deflection is observed with a microscope whose axis coin- cides with the direction of the field. Einthoven used a thread of silvered quartz having a rather large electrical resistance and a long period of oscillation. Korn constructed it of bronze, and as it must carry the diaphragm used for vary- ing the light, it had rather large dimensions. In the first trials Korn, as did all those who had preceded him, used the total variation F'6- 4.—String-galva- ° : nometer. of the resistance of the selenium, but he early saw it was impossible to obtain in that way rapid signals on account of a certain inertia which the selenium had in following the varia- tions of resistance impressed upon it by the light. The resistance of the selenium at each instant depends not only on the illumination to which it is then exposed, but as well upon its previous illumination, and if we wish the cell to return to its normal resistance in the dark it must be given a considerable time. Korn overcame this difficulty through a method of compensation which used the small differential variations in the resistances of two cells—one, e, which is a part of the transmitting system and is submitted to the direct action of the light (fig. 2), the other which serves in the receiver and is placed before the auxiliary lamp, 0, the intensity of the light of which is varied by the string-galvanometer, g. 202 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. The plan of the apparatus (fig. 5) will show how this compensation takes place. Two selenium cells, Se, and Se,, form two branches of a Wheatstone’s bridge, the resistances, A and B, serving for the other 5.—Korn’s apparatus, later form. Fig. twoarms. A battery furnishes the current through two op- posite junctions of the bridge, the line and the galvanometer being connected to the two re- maining junctions. The cell, Se,, is placed in the sending apparatus; it 1s exposed di- rectly to the light transvers- ing the picture which is to be transmitted; the cell, Se,, is lighted by an auxiliary source, obscured by the galvanometer, g, and the apparatus is so devised that as Se, receives hight, the equilibrium of the bridge is broken; but the gal- vanometer, g, in deviating uncovers more or less the auxiliary beam so that Se, becomes illuminated and tends to reestablish the equilibrium. The galvanometer of com- pensation and the receiver, G, receive the same current. The difference between figures 2 and 5 is that, in the working apparatus, the cell and the compensating galvanometer are both at the transmitting station. The Korn system is the only one which has been practically tried with the transmitter sep- arated from the receiver. In the trials between Munich and Berlin, during the year 1907, the transmission of a picture 130 by 240 millimeters, reduced to ap- proximately 35 by 64 millimeters at the receiving station, was ac- complshed in six minutes. These trials were made over a double telephone line and at night in order to avoid the disturbances pro- duced by the neighboring lines. PHOTOTELEGRAPHY—ARMAGNAT. 203 THE TELESTEREOGRAPH OF BELIN. The system of Belin is far simpler and requires, besides photog- raphy, only purely mechanical devices, such that in the trials, al- though they were only local and with no attempts at synchronism, it was possible for him to furnish more practical results than those obtained by Korn, despite the ingenuity and the much-praised devices of the latter. * As we have just said, Belin did not wish to complicate his experi- ments with the problems of synchronism, knowing that there now exist many tried means of solving that part of the problem, and he contented himself with coupling mechanically the transmitter and the receiver side by side. The picture to be transmitted is reproduced upon a bichromate gelatin film. Reproductions of this kind are known to be much thicker where the light has acted the most intensely, and consequently a photograph on such a bichromate gelatin film has a variable relief. This property has, indeed, been made use of in some of the processes of photo-engraving. The bichroma- tized-gelatin film is rolled at G (fig. 6) upon a cylin- der, C, which has a double movement of rotation and translation as in the preceding apparatus. A lever, jointed at its upper part, carries a style analogous to those used with phonographs, and resting firmly upon the film, follows all the reliefs of the latter. These displace- ments of the style are magnified eight times by a lever near its lower extremity; the end of this lever forms a minute contact which moves over the bars of a rheostat, R. The: circuit incloses a battery, the rheostat, R, the line and the receiving apparatus. According to the value of the relief at the point touched by the style, the resistance taken from the rheostat is more or less great, and so the intensity of the current in the line varies. At the receiving station the apparatus consists of a galvanometer, O, whose mirror receives ight from a lamp. The pencil of rays reflected from the galvanometer falls upon a lens so placed that the light which traverses it is always brought to a focus at the point, F, upon the photographic film, A. Before the lens there is placed a screen, T, composed of twenty strips of increasing capacity, called by Belin a “ gamut of tints.” According to the deflection of the galvanometers, that is to say, according to the stilt Fig. 6.—Belin’s apparatus. 204 ANNUAL REPORT_SMITHSONIAN INSTITUTION, 1908. intensity of the current coming over the line, the luminous pencil traverses a part more or less opaque of this “ gamut of tints” and the intensity of the light at F consequently varies. According as the reflected ray passes through a dark or clear part of the “ gamut” when the style of the transmitter is upon a thin or white portion of the film will the result be a positive or a negative. The cylinder, C’, of the receiver is inclosed in a dark chamber and covered with a sensitive film. A metallic screen, pierced with a hole one-sixth of a millimeter in diameter, is situated at F and limits the extent of the film acted upon by this light. And finally, in order to avoid the phenomena of diffraction, BMS) this pierced, metallic screen touches closely the sensitive surface of the film. The reproduced image is formed by the juxtaposition of short lines one- sixth of a millimeter in breadth. We would call attention to two special features in the apparatus of Belin. The rheostat, R, is composed of 20 resistances, the values of which are calculated with due allowance for the resistance of the line so that a proper variation of the current will be reproduced. These resistances are con- nected to a little commutator com- posed of 20 lamine of silver, separated by leaves of mica. This assembly pos- sesses a thickness less than 384 muilli- meters; upon the surface of these lamine works the contact of the lever which is actuated by the relief of the bichromatized gelatin film of the cyl- inder, C. This piece plays an important role and is a most delicate part of the apparatus to construct. In order to obtain a rapid transmission of the signals it is nec- essary to use a galvanometer, at the same time very sensitive and of a very short period of oscillation. Belin employed an instru- ment somewhat widely used to-day in laboratories, the oscillograph of Blondel. This apparatus, represented schematically by figure 7, consists essentially of a flat, extremely fine wire attached between two fixed points, a and 6, and stretched at its lower end by the pulley, p, which is attached to a spring. The whole of this is placed between the poles PP, in the very intense magnetic field produced by the electro-magnet EE. When the current mounts in one of the blades Fic. 7.—Blondel’s oscillograph. PHOTOTELEGRAPH Y—ARMAGNAT. 905 and descends in the other, one of the blades tends to displace itself perpendicularly to the plane of the figure forward, and the other backward; this causes a rotation of its mirror and it is this latter movement which is used for sending the reflected beam of light upon the suitable part of the “ gamut of tints.” In order to have a more exact idea of the dimensions of this galvanometer, let us sup- pose that the poles of the electro-magnet PP, are separated by about 1 or 2 millimeters, that the wire is a ribbon of bronze about 0.02 to 0.03 millimeter in thickness and 0.10 to 0.20 millimeter breadth and finally that the space between the blades is of the order of 0.1 of a millimeter. Such an instrument would have a period of oscilla- tion of about two or three ten-thousandths of a second. As has already been said, Belin has never made any but local trials, the line being looped upon the apparatus. Experiments have been made with a line from Paris, through Lyons, Tulle, Bordeaux, Angouleme, and back to Paris, a qk Ro distance of about 1,717 kilometers. With these con- ditions and a spacing of about one-sixth of a millimeter be- x tween the traces he could reproduce a photograph 13 by 18 centimeters in twenty-two minutes, which, supposing the figure to be composed of points one- sixth of a millimeter on a side, would correspond to 643 signals per second. Belin tried also the transmission of a landscape, which to our knowledge Korn never did; but it seems that he tried to get a trans- mitted picture in too bold relief and that the spacing of one-sixth of a millimeter is too small, especially if the result is to be used for impressions by the photogravure process. By spacing the traces a little farther apart and augmenting the speed of rotation it would seem possible to obtain beautiful results and a greater velocity of transmission. (ZZ Zg Loom 9 . X a ————— at NOTUOUUTNOONN NITION = f SAN BSA ON a sani ; bea\ ; INN ii LLLLLSLENSPLSLLSPLSSSL ASD bo SASS 0\ Fic. 8—Berjonneau’s apparatus. APPARATUS OF BERJONNEAU. Berjonneau used as a transmitter a stereotype plate hatched simi- lar to those used in similigravures. This is rolled upon the cylinder D (fig. 8); all the points of its surface pass under the point of its 206 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. style which a spring F presses upon the plate. As this plate is com- posed of a series of points more and more extended as it is desired to represent a black more and more intense, when the style passes over these points it closes the line through a battery during a greater or less period according to the length of contact touched on the plate and the transmitted signals therefore consist- of a series of currents of the same intensity but of varying duration. A somewhat similar apparatus serves as the receiver. The cylin- der D is covered with a sensitive film and before an opening into its dark chamber is placed a lamp. An electro-magnet placed in the line circuit carries a shutter stopping or allowing the light to fall upon the film; the half tones are due to the length of the points traced by the luminous pencil. APPARATUS OF CARBONELLE. This system recalls the telegraph of Caselli in its use for the trans- mitter of a design traced with greasy ink upon a metallic sheet. His receiver, however, is wholly different. htteonsis tsnotma aaNet telephone the mem- Pila brane of which car- ries a style which engraves in the wax or lead with which the receiving cyl- inder is covered. For transmitting photographs or drawings in half tones, Carbonelle suggests the employment of hatched photographs as was done by Berjonneau. In the trials between Brussels and Antwerp, Carbonelle sent a pic- ture, 13 by 18 centimeters, in eighty seconds. Pie. 9.—Apparatus of Senleeq-Tival. ‘ APPARATUS OF SENLECQ-TIVAL. We will say a few words in closing about an apparatus which has been announced but does not appear to have been tried. In the device of Senlecq-Tival, the photograph to be sent is made by the carbon process, using in the place of carbon a conducting powder, and the prepared plate is rolled upon the metallic cylinder A of the trans- mitter (fig. 9). A style S closes across this film, a circuit con- sisting of a battery, the electro-magnet B and the cylinder A. Each point of the film has a conductivity proportional to the opacity of PHOTOTELEGRAPH Y—ARMAGNAT. 207 the image; consequently the electro-magnet B receives a current which is a function of this opacity. There is next interposed a de- vice, destined apparently to accelerate the transmission, but whose role seems somewhat problematical. Upon the drum C is wound in a helix a steel wire. Every point of this wire passes consecutively under the electro-magnet B, which produces a magnetism proportional to the intensity of the current. This forms the telegraphone of Poulsen. If now O is caused to turn before another magnet connected with the line, in the line there are produced currents which work a string-galvanometer T, which con- trols the light striking the sensitive photographic receiving plate. What is the future of phototelegraphy? At present it would be imprudent to make any prediction. Will a demand be felt for it? Yes, to some extent, especially by the newspapers, which feel a greater and greater need for the rapid transmission of information, often- times in the form of photographs or sketches; by the police for the transmission of the description of criminals, ete. But for all these uses evidently the devices must receive many improvements. On the other hand, is it necessary to wait for the demand before making or improving such apparatus? Evidently it is not, for in that case it would be the organ creating the function. Besides we should recall that these experiments are steps toward seeing at a dis- tance, a problem which does not seem susceptible of direct solution and which, proposed more than thirty years ago, has so far led only to phototelegraphy. The latter may well, however, in its turn, lead us to a solution of the original problem. rae ik Nh habe Seiten vin ne Neth he oe jae i ia, Raa ib | Aare a hiseceamii i : one i THE GRAMOPHONE AND THE MECHANICAL RECORD- ING AND REPRODUCTION OF MUSICAL SOUNDS. [With 2 plates. ] By Lovett N. REDDIE, The mechanical recording and reproduction of sounds has already been dealt with in papers read before this society. The talking ma- chine was introduced to the society on May 8, 1878, by Sir William Preece; on the 28th November, 1888, Colonel Gouraud read a paper Fic. 1.—Earliest and latest types of gramophone. entitled “The phonograph;” and on the 5th of December of the same year Mr. Henry Edwards read a paper on “ The graphophone.” I do not propose this evening to go over the ground covered by these three papers, which deal with the discovery of the talking machine “Reprinted by permission, after revision by the author, from Journal of the Royal Society of Arts, London, No. 2894, Vol. LVI, May 8, 1908, with addi- tional illustrations furnished by Mr. Emile Berliner. 209 210 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. and the improvements made in it up to twenty years ago, but I shall deal more particularly with the invention and the development of a later type of talking machine, and shall describe the various indus- trial and other processes which are connected to-day with the record- ing and reproduction of sound by means of this machine. Before going further I should like to call your attention to two of the instruments before you; the larger machine is one of the latest models of the gramophone and the smaller is one of the earliest types (fig. 1). The difference in appearance of the two machines is striking, but it is small compared with the difference in their capa- bilities, and, if you will allow me, I will make this apparent by en- deavoring to obtain an audible reproduction from the old-fashioned type, and will then play a short selection on the up-to-date instru- ment. The progress made toward perfection during the period of twenty years since the invention of the gramophone has been very consider- able, and so rapid has it been in recent years that too many people to-day when they hear the word “ gramophone ” mentioned imme- diately think of an instrument like this (small machine) and of the sounds which it produced just now. The particular lines upon which improvements have been carried out I will deal with later. The gramophone was invented by Mr. Emile Berliner. At an early age he left his home in Germany and went to America, where he worked for a number of years with great success on telephone con- struction. He afterwards turned his attention to the improvement of the talking machine, and on May 4, 1887, just twenty-one years ago, he filed an application for patent in the United States, and a corresponding application in this country in November of the same year. On May 16, 1888, he exhibited his invention before the Frank- lin Institute, Pennsylvania. At the date of Mr. Berliner’s invention, machines for recording and reproducing sound were already known and in use. Some ten years earlier, in 1878, Mr. Thomas A. Edison had patented the first practical talking machine, and he termed the recording machine, the record, and the reproducing machine a phonograph, a phonogram, and a phonet, respectively. In 1885 the graphophone was invented by Prof. Graham Bell and Mr. C. 8S. Tainter, of telephone fame, who, working as the Volta Laboratory Association of Washington, had been studying the problem of recording and reproducing sound for some years. The fundamental principles on which these two instruments, the phonograph and graphophone, worked were the same. In each case the sound waves set up in the air by any source of sound were allowed to strike a delicately held diaphragm, which vibrated under the impact of the sound waves. The vibrations of the diaphragm were made to leave a record on a suitable medium, and THE GRAMOPHONE—REDDIE. Pala d this sound record was in turn used to perform the inverse operation when it was required to reproduce the recorded sounds; that is to say, the record was made to vibrate a sensitive diaphragm, and this set up in the air particular waves, which conveyed to the ear of the hearer the impression of sound. ‘The essential difference between the Edison and the Bell and Tainter types of sound recording and re- producing machines lay in the manner in which the vibrations of the diaphragm were recorded, for while Edison’s invention consisted in indenting a record with an up and down sound line, Bell and Tainter obtained a record by cutting an up and down line in a suitable me- dium. According to both these inventions, therefore, the vibrating diaphragm was made to produce on the surface of the record a sound line of varying depth. Berliner, on the other hand, traced or cut his record in the recording medium in the form of a sinuous line of uniform depth (fig. 2), “substantially,” as he says in his patent specification, “ in the manner of the phonautograph,” in- vented in 1857 by Léon Scott. The idea of recording and reproducing speech on this system had also occurred to a Mr. Charles Cross, a French- man, who on April 30, 1877, ee ce Nana deposited a sealed packet with Fie. 2.—Section across sound lines of gramo- pices : phone record. (Magnified 50 diam.) the Académie des Sciences, Paris, in which he disclosed the idea of reproducing sound by means of a permanent metal record obtained from a Scott phonautograph by photoengraving through the coating of lampblack in which the sound line was traced. Thus he anticipated Berliner, and Edison as well, as far as the idea went; but he can not be said to have dis- closed the means of carrying his ideas into practice. Mr. Berliner only became aware of this gentleman’s invention three months after he had filed his own application for a patent. In the Electrical World of November 12, 1887, in which he first made public his inven- ‘tion of the gramophone, he writes of Mr. Cross as follows: Although he had virtually abandoned his invention, the fact remains that to Mr. Charles Cross belongs the honor of having first suggested the idea of and a feasible plan for mechanically reproducing speech once uttered. The reasons which led Berliner to adopt a different system of re- cording and reproducing sound from that employed by Edison and the Volta Association are clearly set out in the introduction to his first patent specification, No. 15232, of 1887, where he says: By the ordinary method of recording spoken words or other sounds for re- production, it is attempted to cause a stylus attached to a vibratory diaphragm 212 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. to indent a traveling sheet of tinfoil, or other like substance, to a depth varying in accordance with the amplitudes of the sound waves to be recorded. This at- tempt is necessarily more or less ineffective, for the reason that the force of a diaphragm vibrating under the impact of sound waves is very weak, and that in the act of overcoming the resistance of the tinfoil, or other material, the vibrations of the diaphragm are not only weakened, but are also modified. Thus, while the record contains as many undulations as the sound which pro- duced it, and in the same order of succession, the character of the recorded un- dulations is more or less different from those of the sounds uttered against the diaphragm. ‘There is, then, a true record of the pitch, but a distorted record of the quality of the sounds obtained. With a view of overcoming this defect, it has been attempted to engrave, in- stead of indent, a record of the vibrations of the diaphragm, by employing a stylus, shaped and operated like a chisel, upon a suitably prepared surface; but, even in this case, the disturbing causes above referred to are still present. In addition to this, if in the apparatus of the phonograph or graphophone type, it is attempted to avoid the disturbing influence of the increase of resistance of the record surface, with the depth of the indentation or cut as much as possible, by primarily adjusting the stylus so as to touch the record surface only lightly, then another disturbing influence is brought into existence by the fact that with such adjustment, when the diaphragm moves outwardly, the stylus will leave the record surface entirely, so that part of each vibration will not be recorded at all. This is more particularly the case when loud sounds are recorded, and it manifests itself in the reproduction, which then yields quite unintelligible sounds. It is the object of my invention to overcome these and other difficulties by recording spoken words or other sounds without perceptible friction between the recording surface and the recording stylus, and by maintaining the unavoid- able friction uniform for all vibrations of the diaphragm. The record thus ob- tained, almost frictionless, I copy in a solid resisting material, by any of the methods hereinafter described; and I employ such copy of the original record for the reproduction of the recorded sounds. Instead of moving the recording stylus at right angles to, and against the record surface, I cause the same to move under the influence of sound waves parallel with and barely in contact with such surface, which latter is covered with a layer of any material that offers a minimum resistance to the action of the stylus operating to displace the same. He then proceeds to a detailed description of his instrument, which he terms a “ gramophone.” Nowadays the term “phonograph” is popularly applied to a sound-reproducing machine which plays a cylinder record, while “ oramophone ” is often incorrectly used for any disk machine. This distinction is not, however, correct. It is a fact worth noting that the first figure of the drawings in Berliner’s original patent shows a record wound on a cylindrical support, whereas the first figure in Edison’s patent shows a disk record, thus directly contradicting the popular distinction just referred to. According to the specification of his first patent, Mr. Berliner made his sound record as follows: He took a strip of paper, parchment, or metal, A (fig. 3), stretched it round a drum, B, and coated it with Smithsonian Report, 1908.—Reddie. PLATE 1. Fic. 1.—APPARATUS , 1887-88. Cylinder machine on which first gramophone record was made in 1887. Photograph furnished by E. Berliner. Fic. 2.—RECORDING MACHINE, 1889. Photograph furnished by E, Berliner. THE GRAMOPHONE—REDDIE. OTS a layer of lampblack, or other substance which could be easily re- moved by the point of the stylus. He provided a diaphragm, C, which was held by its edges in a casing, D, and to the center of this diaphragm he attached one end of the recording stylus, E. This stylus or bar was fulerumed halfway down to the side of the diaphragm casing, and the other end was left free to move in accordance with the vibrations of the dia- phragm under the impact of the sound waves. The point of the stylus lightly touched the strip on which the record was to be traced, and as the diaphragm was spoken against, and the drum rotated, the stylus removed the lampblack from the record in a sinuous undulating line. The record thus obtained he proposed to preserve by coating it with varnish or the like. For the purpose of reproduction he copied the record in a resisting material, either mechanically, by engraving, or by etching, or photo-engraving, and this gave him a permanent record, consisting of a wavy grooved line in a strip of copper, nickel, or other material. To reproduce the sounds recorded, this strip was in turn stretched round a drum, the point of the stylus placed in the groove, and the drum rotated. This caused the diaphragm to which the other end of the stylus was attached to vibrate and reproduce the recorded sounds. The specification continues: Fic. 3.—Model of first gramophone patent. In the phonograph and graphophone the end of the reproducing stylus which bears upon the indented or engraved record, has a vertical upward and downward movement ; it is forced upwardly in a positive manner by riding over the elevated portion of the Fig. 4.—Berliner recording dia- yecord, but its downward movement is ef- ee Hee es ce Nes, - (Cut fected solely by the elastic force of the dia- phragm, which latter is always under ten- sion. In my improved apparatus the stylus travels in a groove of even depth and is moved positively in both directions; it does not depend upon the elasticity of the diaphragm for its movement in one direction. This I consider to be an ad- vantage, since by this method the whole movement of the diaphragm is posi- tively controlled by the record, and is not affected or modified by the physical 214 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. conditions of the diaphragm, which conditions necessarily vary from time to time, and constitute some of the causes of imperfect reproduction of recorded sounds. It is this feature of the positive control of the diaphragm, coupled with the uniform friction and resistance in the cutting operation, and the consequent accurate tracing of the curve of the sound wave, that has brought the Berliner type of machine to the forefront as a musical instrument. While the cylinder machine with the up and down cut offers advantages for making records at home and for office work, being handier, for instance, than the disk recording machine, it has not been found possible to obtain the same truth of repro- duction of musical sounds that can be obtained with the gramo- phone. An examination of the Fig. 5.—Berliner reproducing apparatus microscopic undulations in the (1888). (Cut furnished by E. Berliner.) sound wave, which determine its pitch, loudness, and quality of timbre (some examples of which I shall show you presently), will make this easy to understand. In the second or improved form of gramophone described in Ber- liner’s patent, a flat disk record is used, which, he says, offers advan- tages for copying purposes. Here a disk of glass is employed, and this is covered preferably with a semifluid coating of ink or paint, in which the stylus traces or cuts an undulating line as before. This coating he prefers, because it does not flake and leave a rough-edged line, like the lampblack record. A turntable carries ee orn the record disk, and is rotated by any suitable means. ie pege aaa As it revolves it is caused to travel slowly sideways past the recording point, so that the sound line takes § ~—~—~__~ the form of a sinuous spiral running from the outer =“ ~~~ edge of thewrecord| toward: thercenter, or vice) versay) 7 en ee A permanent record in metal is obtained by photo- lines (1888). x engraving. a Mr. Berliner’s next step was to make a disk record _ Berliner. in solid material by direct etching. (United States patent 382790.) To this end he coated a disk or cylinder of zine or glass with a layer of some substance which, while offering no perceptible mechanical re- sistance to the movements of the recording stylus, resisted the chemical action of acids. The coating he preferred consisted of beeswax dis- solved in benzine. When the recording stylus had traced out its line on the record, and exposed the solid disk below, the latter was etched, THE GRAMOPHONE—REDDIBE. 215 and a permanent record produced. Copies could be obtained by the galvano-plastic process, by making a matrix, and impressing disks of hard rubber or the like. Although this system of etching was considered at the time a great advance in sound recording, it never gave very satisfactory results. Owing to the action of the acid, which, besides biting down into the metal, also undercut the pro- tective coating, the sound line was always left with rough sides, and this roughness was transmitted to the copies, so that the reproduction was accompanied by a very marked and disagreeable scratching sound. In 1890 the inventor of the gramophone took out patents for fur- ther improvements, and in particular for new forms of diaphragm Fic. 7.—Replica of gramophone apparatus used at Franklin Institute, May 16, 1888, the first public exhibition. Now in Deutsches Museum at Munich. (Photograph furnished by E. Berliner.) holder, or sound box, as it is called, one for recording purposes and the other for reproducing (fig. 8). Although at this date Mr. Berliner himself had spent much time on improving his invention, the gramophone had not yet become a commercial article. It had not even reached the stage of the small machine you see here. It was looked upon as a scientific curiosity, or at best a toy, but not as a machine which could ever be expected to become an instrument of entertainment, and no one, except, perhaps, the inventor, ever imagined it would attain its present perfection or enjoy its present popularity. The phonograph and graphophone had obtained a firm footing, and for commercial purposes, at any rate, serving, for instance, as automatic stenographers, and in a lesser degree as instruments of entertainment, had attained success. 88292—sm 1908——15 216 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. The Volta people had patented broadly the system of cutting or tracing a sound line in a solid body, so that even Berliner’s own method was within the scope of their patent, and from the point of view of patent rights, Mr. Berliner was at a disadvantage. More- over, the reproduction he obtained was far behind that given by the phonograph and graphophone, for though in the latter instruments the sound waves were distorted, there was a comparative absence of scratch. Very different is the position to-day when in the United States at any rate practically the whole of the enormous trade in disk machines is subject to a Berliner patent No. 534543, which covers the use of a freely swinging sound arm or horn, carrying the sound box and guided throughout the playing of the record entirely by the sound lines. It was not until the end of 1894 that the manufacture commenced in the United States of a disk record which quickly made the gramo- phone popular, and may be re- garded as the starting point of the industry of to-day. Instead of a record made from an etched metal original, a disk record could now be offered to the public made by a new pro- cess which allowed many hun- dreds of good facsimile copies to be made from one master record. This process consisted Fig. 8.—Recording and reproducing sound a Cikim2 the first record as tamesh SUL Re disk-shaped blank of wax-like material, obtaining a_ solid metal negative thereof by electro-deposition, and pressing copies of the original from this negative or matrix in a material which was hard at normal temperatures, but became plastic under heat. About this time a number of inventors began to turn their attention to the improvement of the machine, to keep pace with the vast improvements which were being made in the records. The machine was provided with an efficient governor or speed regulator to insure a uniform speed of rotation of the turntable. Next the hand-driven machine was abolished altogether, and a machine substituted which was driven by a spring motor. To-day the better-class machines are furnished with a motor which will run fifteen minutes or more for one winding of the motor. The speed regulator was furnished with an indicator to show at what speed the machine was running. It will easily be understood how essential it is that the record on reproduc- tion should be revolved at exactly the same pace as the blank on which the original record was cut, if the production is really to be a THE GRAMOPHONE—REDDIE. Oley: true reproduction of the original selection; if, for instance, the record is rotated faster, the sound waves set up by the reproducing dia- -phragm will be produced at a higher speed than that at which the corresponding sound waves fell upon the recording diaphragm. The greater the frequency of the sound waves the higher the note, so that a record, if played too fast, is pitched in a higher key, and a bass solo can be reproduced in a shrieking soprano. The sound box went through a series of improvements, the object of the inventors being to render the diaphragm as sensitive as pos- sible either to the sound waves of the selection being recorded or to the vibrations transmitted to it from the record disk, as the case might be. The diaphragm is now lghtly held at its edges by hollow rubber gaskets, the fulcrum of the needle connecting the diaphragm to the needle point is formed by knife edges, and its movements are controlled by delicate springs. The standard sound box of to-day is a very different thing from the early patterns shown in figures 1 and 8. Improvements were further made in the means of conveying the sounds recreated in the sound box to the ear of the auditor. The old ear tubes had disappeared to give place to a small horn, to the narrow end of which the sound box was attached. As the popularity of the gramophone grew, the public wanted more sound for its money, and accordingly the size of the amplfying horn was increased. The increased weight of the horn necessitated that a special bracket should be provided to carry it, and the horn was accordingly balanced with just sufficient weight on the sound-box end to keep the needle well in contact with the record. Thus the machine remained for a time, but in this form it did not satisfy its patrons, for it did not do all that they thought might be expected of it. It was found in practice that the turntable often did not revolve absolutely horizontally, that the record disks were sometimes not absolutely flat, and that the central hole was in reality but seldom accurately in the center of the disk. Owing to the rise and fall of the record as it rotated, the end of the amplifying horn also had to rise and fall, and owing to the eccen- tricity of the hole in the middle, the sound-box end of the horn was continually approaching and receding from the center of the record, as it followed the sound line. In other words, the needle as it fol- lowed its path along the sound groove, in addition to transmitting the proper vibrations to the diaphragm, had also to move the whole mass of the amplifying horn. This had two injurious effects; it impaired the reproduction, and it wore out the record. The next step was to remove the amplifying horn to a short dis- tance from the sound box and to carry it upon a rigid bracket on the cabinet of the instrument, the sound box being connected to the small end of the horn by a piece of tubing, which allowed the sound box to 218 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. move across the turntable and also to be raised or lowered above the record. This arrangement offered the advantage that the weight of Mires 79: Tapering sound arm (a). the horn was carried by the- cabinet, and the record had not to overcome the inertia of the whole horn as before, but only had to move the sound box and its connecting tubing (or sound arm as it iscalled) when the turntable was not hori- zontal or the hole in the record not central. But though this arrangement offered advan- tages in one direction, it was found to be accompanied by imperfection in another. The piece of straight tubing connecting the sound box and the horn had a dis- torting effect upon the sound waves. Instead of these waves being able to expand uni- formly as they ad- vanced, as had been the case in the old arrange- ment when they passed straight into the horn, they were forced to pass first of all through this straight pipe where the waves became dis- torted and acoustic in- terference was created. It was not until 1903 that patents were taken out on an invention which overcame this difficulty (fig. 9), the invention now known as the taper arm, the patent on which in this country was recently upheld in the court of appeal. The inventor had hit upon the idea of jointing the amplify- Vic. 10a. Wie. 10b. Some various stages of development of the gramophone. ing horn itself, so that while the horn could start immediately next the sound box the latter could be moved with freedom without mov- THE GRAMOPHONE—REDDIE. 219 ing the heavy bell portion of the amplifying horn. The success of this invention was immediate and pronounced, and a tapering sound arm is now almost a sine qua non. It was only to be expected that as the reproduction of the machine improved the form in which it was presented to the oo would be more and more attract- ive, and hence the hand- some cabinets and pedes- tals with which the gramophone is furnished to-day. Figure 10 shows some of the various stages through which the ma- chine passed. The in- strument 10¢ will be rec- ognized as the one before which the dog sat and Fie. 10¢. listened to “ his master’s x voice.” An important item in the reproducing appa- ratus is the needle. In- stead of the same blunt point being used over and over again as form- erly, a new needle is now recommended for each playing of a record. The reason is that the opera- tion of playing a record wears down the fine point of a needle, so that by the time a record has been played through, the . needle point has shoul- Some various eee es, of the ders worn on it (fig. s131)) gramophone. with only a central projection left to engage in the sound groove; a point of this shape when much worn can not give a good reproduc- tion. The manufacture of gramophone west constitutes a small industry in itself, and the number of processes through which the needles go before “hee are ready for use is surprising. Lengths are cut from the best steel wire, and are pointed by emery wheels, rotating about 1,200 times a minute. The needles are cut off, and again the blunt ends are pointed. Some of the machines in use cut off as many 220 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. as 200,000 needles daily. The needles are now hardened by temper- ing, being heated in open pans, almost to white heat, and then sud- denly cooled; this is a most important process. They then have to be polished. This is done by packing the needles into bags or sacks and rolling them to and fro for days on a reciprocating table; the constant friction of the needles against one another polishes them bright and smooth. I will now deal with the series of operations which go to make a finished disk rec- ord of the Berliner or gram- ophone type. The person who is making the record sings or plays immediately before the mouth of a horn or funnel, the object of the horn being to concentrate the energy of the sound waves upon the recording diaphragm. At the narrow end of the horn is the recording sound box and machine and its attendant expert. The artist is on one side of a screen and the machine on the other, for in all the recording laboratories of talking-machine manufacturers the secrets of the operation of recording are most carefully guarded. I have here a sketch (fig. 12) drawn by a famous singer of himself making a record. The making of a good rec- ord is not so simple a matter for the artist as might appear; he often has to make sev- eral trials before he learns just how to sing into the trumpet, how near to stand, ete. When singing loud, high notes he must not come too near the mouth of the funnel, as otherwise the vibrations will be too powerful and the result will be what is technically known as “ shattering.” When the artist is singing or playing to an accompaniment another horn connected with the same sound box is often provided so that the person of the artist may not obstruct the sound waves of the orchestra or other accompaniment. Fic. 11.—Sections of needle point. Fig. 12.—Making a gramophone record. > = Smithsonian Report, 1908.—Reddie. PLATE 2. Fic. 1.—1894 GRAMOPHONE. Photograph furnished by E. Berliner. FiG. 2.—MULTIPHONE. Photograph furnished by E. Berliner. THE GRAMOPHONE—REDDIE, 2921 The disposition, too, of the various instruments of an orchestra in the recording room is of the very highest importance if the best re- sults are to be obtained. The wooden instruments are arranged about 4 feet from the mouth of the trumpet; behind them are the brass instruments, and at the back the bass fiddles and drums. On the other side of the screen a horizontal table, carrying a wax tablet, is rotated beneath the recording sound box at a fixed and uni- form speed, generally about 76 revolutions per minute. As the table rotates it also travels laterally at a fixed and uniform speed, being carried on a revolving threaded spindle, and the wax tablet or blank is thus caused to travel slowly under the stationary recording box. The sapphire cutting point of the sound box is lowered so as to enter the surface of the blank to the depth of about 0.0035 to 0.004 of an inch, and as the ma- chine runs it cuts a fine spiral groove of uniform depth, run- ning from the cir- cumference of the blank to within 2 or 3 inches of the center, according to the length of the selec- tion recorded. The exact construc- tion of sound box used for recording is 6 ° \ not disclosed by the ie. 13—Recording sound box. A, stylus; a, stylus bear- = ‘ + i ; B, diaphragm; C, diaphragm holder; D, flange of ex ; we me ings; B, diaphrag ; D, perts, but we m ay, sound tube; E, counterweight. take as illustrative two forms which are covered by British patents, Nos. 659-01 and 627-01 (figs. 13 and 14). The turn table travels, as a rule, about 0.01 of an inch laterally for every revolution, so that the spiral cut comes round about 100 times in the width of 1 inch. It will thus be evident that the lateral undu- lations of the sound line must be minute in the extreme as otherwise the lines would at points break into one another. The recording blank is made of a soapy wax. Each laboratory has its own receipt for the composition of the blank, but generally speak- ing the compound is made up of stearin and paraffin. Many other substances have been suggested, among which may be mentioned barium sulphate, zine white and stearin, ozokerit and paraftin. The consistency of the blank material must be such that it is stiff enough to retain its shape when the sound groove is cut in it, and at the same time it must not be so stiff as to offer any great resistance 222 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. - to the cutting point. It must not chip nor flake, as otherwise the recording point will cut a groove with ragged sides, and this will increase the scratching sound made by the needle on subsequently reproducing. The best results are obtained by a tablet of such con- sistency that the cutting point detaches an unbroken thread or shav- ing of wax. The diameter of the recording blank varies, but the maximum diameter employed is about 12 inches. It will be clear that the size of the record can not be increased beyond certain limits, when it is remembered that the blank is revolved at a uniform speed, and that consequently the outer portion of the blank is running past the recording point at a much higher speed than the inner portion, when this is brought under the recording sound box. Thus, with a 12-inch disk, when the cut- ter is one-half inch from the edge, it will in 1 revolution describe a line on the record of a length approxi- mately equal to the circumference of a circle of 11 inches diameter—that is to say, 34.5 inches. By the time the record- ing point has worked in another Fig. 14.—Recording sound box. A, stylus; a, stylus bear- 3 inches toward the Dee diaphragm; C, diaphragm holder; D, tension center of the tablet the length of its path over the wax will approximately equal the circumference of a cir- cle of 5 inches diameter, or 15.7 inches. The rate of revolution of the tablet being uniform, the sound line at the edge of the tablet is accord- ingly being cut at more than twice the speed that it is cut at nearer the center, and the speed at which the recording point can be made to cut the sound groove satisfactorily can only be varied within certain limits. If the diameter of the tablet is increased the outside speed will be too great for proper recording, and if the speed of the turn- table is correspondingly decreased the ripples in the sound line near the center will be too close together and cramped. There will be too many vibrations per inch of sound line to allow of proper recording and reproduction. The obvious solution would be, of course, gradu- ally to increase the speed of the turntable as the recording point THE GRAMOPHONE—REDDIE. Ios nears the center of the blank, but there then arises the necessity of using mechanism for securing a corresponding gradual change of speed on the reproducing machine in order to keep the selection in the proper key. Devices for securing an increasing speed have been invented, but they are not free from objection, and have never come into general use, The record in wax having been made, the next step is to produce a negative in copper. The wax tablet is dusted with graphite, which is worked into the grooves with a badger-hair brush, to make it elec- tro-conductive, and is lowered into the electrolytic bath of copper salt solution. In order that this negative may be able to resist the pressure to which it is subjected in pressing records, jt is necessary that the deposition of the copper should be thoroughly homogeneous. To this end, and also in order to hasten the process so that the blank may not be attacked by the solution, the blank is kept continuously in motion in the electrolytic bath. The process is continued until the copper shell is nearly 0.9 of a millimeter in thickness. The negative thus formed may be termed the master negative, and from this master a few commercial samples of the record can be pressed by means of which the quality of the record can be tested. It is not, however, usual to press more than two or three records from this negative. Seeing that sometimes as many as six thousand or more copies are sold of a single record, it is natural that the manufacturers should take steps to enable them to multiply copies without injuring their master negative or having it worn out, for it is not usual at this stage to obtain further negatives from the original wax record. They accord- ingly make duplicates of their master negative, by taking dubs or impresses of the master in a wax composition, from which in turn working matrices are made. Copper shells are obtained from these dubs in the same way as from the original wax tablet, but the metal is only deposited to the thickness of about half a millimeter. The shells are made absolutely true and flat at the back, so that any irregu- larities caused in the electro-deposition may not be transferred in pressing to the front or face of the shell. They are then backed up or stiffened by a brass plate about one-tenth of an inch in thickness. The attachment of the backing plate and matrix is effected by sweat- ing or soldering them together under pressure. The backing plate is supported on a heated table, a thin layer of solder is run over it, the shell is laid upon it and pressed firmly down, with an elastic pro- tective cushion of asbestos, for example, placed over the face or re- corded surface of the shell to prevent the sound ridges in it from being injured. The matrix thus obtained is now nickel plated on the recorded side so as to present a better wearing surface, and after polishing is ready for use in the pressing machine. 224 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Attempts have been made to use a recording blank of conductive material, or containing sufficient conductive material to allow of omitting the subsequent graphiting or metallising of the blank; the objection to this procedure has always been that such substances offered too much resistance to the recording point. The commercial record is pressed in a substance the essential quali- ties of which are that it should be hard at normal temperature, but capable of being softened and made plastic by heat. It must be tough and elastic enough not to be easily broken when pressed into disks of about 24 mm. in thickness; it must be thoroughly homogeneous; and it must not be gritty in composition, as otherwise it will augment the scratch of the needle, and wear off the point. Finally, the record must be so hard, when cold, that it will retain the contour of the sound groove, even after it has been played a large number of times. Various substances and compounds have been used or suggested for making records; celluloid, glass, papier-maché, vulcanized rubber, easein, and shellac with an admixture of crocus powder. In nearly all the compounds actually used shellac is the principal ingredient. The compound usually employed to-day is made up of shellac, wood charcoal, heavy spar (barium sulphate), and earthy coloring matter. Various animal and vegetable fibrous materials, such, for instance, as cotton flock, are added to give the record the required toughness. The several ingredients are first finely ground and then carefully meas- ured and mixed according to formula. The mixture is put into a revolving drum, and the flock added. After being passed through a magnetic separator to remove any metallic particles, it is next mixed by heated rollers until a thoroughly homogeneous plastic mass is ob- tained. The mass is now passed through calendar machines which roll it out into thin sheets, and as it passes from the calendar it is divided into sections, each section being about the requisite quantity for one record. The records are pressed in hydraulic presses. The matrix is heated and placed face upward in a mold on the lower half of the press, being centered by a pin passing through the middle of it; the label for designating the selection is placed face downward in the matrix, and on this is placed, in a warm, plastic state, the quantity of material required for one record. The press is operated, and the mass is imme- diately distributed all over the mold. Both halves of the press are furnished with cooling plates, through which a stream of water can be passed so that the pressing surfaces can be immediately cooled, and the record mass consequently hardens quickly and retains the impressions of the matrix. The record is removed, and its edges are trimmed up with emery wheels; for the record material is too hard to allow of any cutting instrument being used. The record is then ready for sale. THE GRAMOPHONE—REDDIE. . 225 It will be seen that the process of producing a commercial record is a long and intricate one. It is, further, a process or series of processes which have required a very high degree of scientific skill and untiring experimental work to bring the sound record to its present pitch of excellence. There are still objections to be over- come, and perhaps the greatest of these is the hissing or scratching sound produced by the needle in reproduction. There is, however, no reason to doubt that eventually this will be overcome. A material will be found for making the records which will insure that the sides and bottom of the sound groove are absolutely smooth. Even this, however, will not entirely eliminate the scratch, which must be re- garded to some extent as inherent in the sound groove. The recording point makes a slight hissing noise as it cuts the wax, and that means that the recording point is vibrating on its own account, apart from the vibrations which it is conveying from the diaphragm to the wax tablet ; consequently we must expect the recording point to be regis- tering its own scratch vibrations as it goes along. These scratch vibrations are exceedingly minute and of a very high frequency, and in the ordinary course might not be heard were not the diaphragm abnormally sensitive to vibrations of high frequency ; the actual result is that the scratch waves are reproduced with proportionately more precision, if anything, than the musical waves of the selection. An invention has recently been published which, if practicable, should do much to remove the defect of scratch. According to this invention the stylus of the recording sound box, instead of. cutting a groove in a wax blank, is made to deposit a fine stream of material upon a polished surface. The original record, therefore, has a raised sound line on it, instead of a grooved one. The substance deposited is one which quickly hardens on deposit, so that it will not spread on the polished surface. A negative is made from this original, and the matrix used for pressing is made from this negative. Much attention has been bestowed on the diaphragm both of the recording and of the reproducing sound box. Diaphragms have been tried of almost every possible substance. Copper, tin, celluloid, rubber, leather, gold-beater’s skin, animal membrane, glass, and mica have all been used, and as many different methods of supporting them in the sound box have also been tried. The object aimed at is to secure a light and highly sensitive diaphragm, and to hold it in the sound box so that in vibrating under the impact of the sound waves it will buckle as little as possible, for the effect of buckling is to slightly distort the sound waves. A glass diaphragm is usually employed in recording sound boxes, one being selected out of a score that may be triéd. Reproducing sound boxes are now always made with mica diaphragms. 226 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Tt is interesting to note that steps are to-day being taken in many countries to form collections of voice records of singers, artists, and Fig. 15.—A, motor; B, blower; C, oil sepa- rator; D, air reservoir; E, dust extractor; F, electric switch; G, fuse box; R, turn- table motor; V, turntable. other famous personages, and that an important part is played by the talking-machine record in science. In June of 1906 a number of matrices were deposited at the British Museum of records made by well-known artists and others. These have been sealed up, and are not to be taken out for fifty years. Thus records of these artists’ voices have been secured for practically all time. On the 24th of December, 1907, there were deposited in a vault of the Paris Opera House disks bearing records of the voices of Tamagno, Caruso, Scotti, Plancon, de Lucia, Patti, Melba, Calvé, and other artists. The statute establishing this collection provides that Wie, 16.—Pneumatic sound box and arm in operation. the records shall be taken out and played once every hundred years. The collection is to be added to every year. THE GRAMOPHONE—REDDIE. 297 Austria has had a public phonogram record office since 1903. Doc- tor Poch, who recently returned from two years wandering among the tribes of South America, brought with him many records of religious, ceremonial, and other songs, which are of great ethnological interest. YL C A—— 3 on In Germany, although no public office = 4 has as yet been established, the German ty 1s Anthropological Society and the Ethno- “ae a t— Al logical Museum each have their collections. S A short time ago the Hungarian Ethno- logical Museum purchased a number of machines, and appointed a certain Dr. Vikar Bela to travel through Hungary and to make records of the various dia- EZ lects found there, in order that the folk ¢ songs of the people might be preserved. The records have been registered and are Fie. 17.—Sectional view of pneu- preserved in the archives of the museum. Bisute) Souna bor. Professor Garner, of the United States, is reported to have taken records of the sounds made by the West African apes, and to be able clearly to distinguish certain sounds betokening, for instance, fear, hunger, friendship. He described how he established himself in a cage in the forest where the apes came and visited him; he held in fact a sort of school which was attended by carefully chosen pupils. The story is known of Humboldt finding a parrot in Brazil which was able to speak an otherwise extinct Indian dialect. The scientists of the future will, as you see, have more reliable sources of information in the talling- machine record. T have here some records made by the Pigmies of Cen- tral Africa, who were brought on a visit to this country by Colonel Harrison. If you will permit me I will give you a Pigmy follk song with national accompaniment. This paper on Mr. Berliner’s invention, and the recording and reproduction of musical sounds, would not be complete if I omitted to refer to another instrument, that now known as the Auxeto- Gramophone or Auxetophone, which works on a different principle, Z SSSA NNSA SONNE SS3 5 Fic. 18.—Valve of pneumatie sound box. 228 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. but by means of which sound records of the Berliner type can be most effectively reproduced. In this machine the record does not vibrate a diaphragm, but it vibrates a very finely adjusted valve which controls the flow of a column of air under pressure. As the air passes through the valve there are given to it minute pulsations, which correspond to the undulations in the sound record, so that sound waves identical with those originally recorded are set up in the surrounding air and travel to the ear of the hearer. In the apparatus you see here (fig. 15), a one-sixth horsepower electric motor drives an air compressor. The air, after passing through an oil separator or filter, enters a reservoir, which helps to insure a regular flow of air to ae valve.. From the reservoir the air passes through a dust collector before it reaches the valve, as the very fine adjustment of the latter is apt to be interfered with if particles of dust or oil get into it. The sound box, as you will see on refer- ring to the drawing, comprises a vibrating comb or grid valve, rigidly connected to the stylus bar or needle holder, and a _ grid valve seat. The valve is on the side of least pressure, and is carried by a spectacle spring (58, fig. 18). The air is deflected to the walls of the sound box by a conical deflector, so that it reaches the whole of the surface of the valve at uniform pressure. A resilient rubber washer holds the grid valve normally against the valve seat. As the needle moves, following the sinuosities ae the sound line, the valve moves with it, and thus opens and closes more or less the slots in the valve seat through which the air is rushing. The effect of this I will let you hear for yourselves. Fig. 19.—Parson’s sound box. Se ye Re NAA <—V Fig. 20.—Note of orchestra: 0.5 second. THE GRAMOPHONE—REDDIE. 229 The first practical talking machine working on this principle was made by Mr. Short, who patented his invention in 1898. The Hon. C. A. Parsons then took up the invention, and considerably improved it. Ihave a model here of the improved Parsons sound box (fig. 19). The auxetophone sound box as used to-day is on substantially the same lines, though its construction has been simplified. Before closing this paper I should like to give you some details concerning the sound line in a gramophone record, and show you some magnified trac- ings of sound waves. The approximate length of the spiral line in a fully recorded 12-inch record, carry- ing the sound line to within 21 inches of its center, is ~ times the mean diameter multiplied by the num- ber of turns—that is, a X 8 X 350 inches = 244 yards 1 foot. But this is the length of the line without the ripples. These at least double its length, if the pitch of the record is high and the sounds recorded rich in harmonics, so that we have a sound line over 480 yards long. It is no wonder that the needle point must be finely tempered, and that it shows signs of wear after playing a record. Its average speed over the record is 31.8 inches per second. For a fundamental note on middle C, this gives us about 8 vibrations per inch. The tracings which I have here are some made by Professor Scrip- ture of Washing- ton, and are reproduced in his interesting work, Researches in Experi- mental Phonetics. They are traced by a specially constructed instru- ment from actual gramophone records, and they show the sound line on a very much magnified scale. The “ time equation ” of the tracings shown by, Professor Scripture is 1 millimeter = 0.0004 second—that is to say, 1 millimeter length of the tracings shows the sound waves produced in 0.0004 of a second, or 8.2 feet per second. The reproductions shown in the figures are about half full size, so that 4.1 feet equals the length of tracing for 1 second. Fic. 21.—Gong: 0.4 second. Fig. 23.—Plucked string: 0.05 second. 230 ei g tee S é Cane Oa ; m ¢ ¢ rie dow van ie ( | ( oe ) ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 24,—Tremolo: 0.4 second. Fig. Figure 20 shows the waves of a note of an orchestra, produced in just under 0.5 of a second ; a vibration with a wave length of about 3 milli- meters is noticed occurring again and again. These are seen to be grouped in threes, indicating a tone with a period of 9 millimeters. The pres- ence of loud bass notes is indicated by the greater amplitude of certain waves. There is one which reinforces every sixth vibration; a very compli- cated curve is the result. It is marvelous that the ear can sift these vibrations so as to dis- tinguish the notes of the various instruments from one another. Figure 21 shows the vibrations of a gong. The gong is struck, but the special vibrations do not commence immediately. The curve of the low fundamental has other high vibrations traced in it. When the chief tones of the gong interfere they produce beats, as shown in the weak portions. Figure 22 shows the curve of a whistled note accompanied by piano. The waves of the piano note alone can be distinguished from those where the high whistle vibrations are imposed. Figure 23 shows the curve of a plucked string. Vigure 24 shows a small portion of a vocal record of an Italian voice on a high note. The rise and fall of the amplitude is noticed, pro- ducing a tremolo; the pitch, however, does not rise and fall as it would in a proper trill, which is supposed to be an alternating between two notes. The distinction, however, between the tremolo and trill could not be distinguished by the ear. Finally, figure 25 shows part of a tracing from the legend of “ Cock robin’s death and burial.” It starts with the fly’s response, “ With my little eye, I saw him die.” Attention may be drawn to the five occurrences of the vowel sound “ ai,” in. “my,” “eye, yd? todas” al. anne hemes of the two components, the “ah” and the “e” are easily recognized each time they occur. It will be noticed further that the consonants are practically silent and leave an imperceptible record. THE GRAMOPHONE—REDDIE. 2S That concludes my paper. JI have an instrument here which will enable you to see the curve of the actual sound waves of a record being produced by means of a spot of light reflected from a small iaivAbstionsutn A eS Pa « £%] :” 6.5 sec, ae ccentctttetitnted ental totes einiatel sone LY) state Fia. fi CT Ree aa cao rh : : AIA LAVATAVAVAVAVAVAV A VVAtatvatataa tates : fa} - : eae #3 tt} ‘ ira Le > A Vee Te ee i f fe ’ te faye eye | oF Baling PREY WIN rar PI aL ROS WN ($77 25.—Part of “Cock Robin Veterans (37 ANAAAIWnannndancn Tt a “3 iy Ke “f th ae AYA VAVALAYAVAUAVA bee A ot area (11. ALAS TM RR cc ren res ae RSI ' a i im Lc i Ut nD ee DIAL (TT: Nc fae (reese ny 4 Le) 19 mirror attached to a gramophone diaphragm on to a revolving mirror and thence on to a screen. The apparatus is one invented by Mr. G. Bowron. 88292—sm 1908——16 ie ri a a paral ditt ate re Gite Gh ons nt ON THE LIGHT THROWN BY RECENT INVESTIGATIONS ON ELECTRICITY ON THE RELATION BETWEEN MAT- TER AND ETHER? By J. J. THomson, D. Sc., F. R. S., Cavendish Professor of Experimental Physics in the University of Cambridge. When I received the invitation to give the Adamson memorial lec- ture I felt considerable hesitation about accepting it. I felt there was some incongruity in a lecture founded in memory of a great master of metaphysics being given by one who had no qualifications to speak on that subject. I was reassured, however, when I remem- bered how wide were Professor Adamson’s sympathies with all forms of intellectual activity and how far-reaching is the subject of meta- physics. There is indeed one part of physical science where the problems are very analogous to those dealt with by the metaphysician, for just as it is the object of the latter to find the fewest and simplest conceptions which will cover mental phenomena, so there is one branch of physics which is concerned not so much with the discovery of new phenomena or the commercial application of old ones, as with the discussion of conceptions able to link together phenomena appar- ently as diverse as those of light and electricity, sound, and mechanics, heat and chemical action. To some men this side of physics is pecu- harly attractive; they find in the physical universe with its myriad phenomena and apparent complexity a problem of inexhaustible and irresistible fascination. Their minds chafe under the diversity and complexity they see around them, and they are driven to seek a point of view from which phenomena as diverse as those of light, heat, electricity, and chemical action appear as different manifestations of a few general principles. Regarding the universe as a machine, such men are interested not so much in what it can do as in how it works and how it is made; and when they have succeeded, to their own satis- faction at any rate, in solving even a minute portion of this problem they experience a delight which makes the question “ What is the “The Adamson lecture delivered at Victoria University of Manchester, Eng- land, November 4, 1907. Manchester University Lectures, No. 8. University Press, 1908. Reprinted by permission of the author and the publications com- mittee of the university. 233 234 ANNUAL REPORT_SMITHSONIAN INSTITUTION, 1908. value of hypothesis?” appear to them as irrelevant as the questions “ What is the value of poetry?” “ What is the value of music?” “What is the value of philosophy ? ” Recent investigations on electricity have done a good deal to unite various branches of physics, and I wish this evening to call your attention to some of the consequences of applying the principle of the equality of action and reaction—Newton’s third law of motion— to some of these researches. According to this law the total amount of momentum in any self-contained system, that is, any system un- influenced by other systems, is constant, so that 1f any part of such a system gains momentum another part of the system must simulta- neously lose an equal amount of momentum. This law, besides being the foundation of our ordinary system of dynamics, is closely con- nected with our interpretation of the great principle of the conserva- tion of energy, and its failure would deprive that principle of much of its meaning. According to that principle the sum of the kinetic and potential energies of a system is constant; let us consider a moment how we are to estimate the kinetic energy. To us the objects in this room appear at rest, and we should say that their kinetic energy was zero, but to an observer, say on Mars, these objects would not appear to be at rest but moving with a considerable velocity, for they would have the velocity due to the rotation of the earth round its axis and also that due to the revolution of the earth round the sun; thus the estimate of the kinetic energy made by a Martian observer would be very different from our estimate. Now the ques- tion arises, Does the principle of the conservation of energy hold with both these estimates of the kinetic energy, or does it depend upon the particular system of axes we use to measure the velocity of the bodies? Well, we can easily show that if the principle of the equality of action and reaction is true, the conservation of energy holds what- ever axes we use to measure our velocities, but that if action and reaction are not equal and opposite this principle will only hold when the velocities are measured with reference to a particular set of axes. The principle of action and reaction is thus one of the founda- tions of mechanics, and a system in which this principle did not hold would be one whose behavior could not be imitated by any mechanical | model. The study of electricity, however, makes us acquainted with cases where the action is apparently not equal to the reaction. Take for example the case of two electrified bodies, A and B, in rapid motion. We can, from the laws of electricity, calculate the forces which they exert on each other, and we find that, except in the case when they are moving with the same speed and in the same direction, the force which A exerts on B is not equal and opposite to that which B exerts on A, so thati the momentum of the system formed by B and A does not remain constant, Are we to conclude from this result MATTER AND ETHER—THOMSON. 935 that bodies when electrified are not subject to the third law, and that therefore any mechanical explanation of the forces due to such bodies is impossible? This would mean giving up the hope of regarding electrical phenomena as arising from the properties of matter in motion. Fortunately, however, it is not necessary. We can follow a famous precedent and call into existence a new world to supply the deficiencies of the old. We may suppose that connected with A and B there is another system which, though invisible, pos- sesses mass and is therefore able to store up momentum, so that when the momentum of the A and B system alters, the momentum which has been lost by A and has not gone to B has been stored up in the in- visible system with which they are in connection, and that A and B plus the invisible system together form a system which obeys the ordinary laws of mechanics and whose momentum is constant. We meet in our ordinary experience cases which are in all respects analo- gous to the one just considered. Take for example the case of two spheres, A and B, moving about in a tank of water. As A moves it will displace the water around it and produce currents which will wash against B and alter its motion; thus, the moving spheres will appear to exert forces on each other. These forces have been cal- culated by Kirchhoff and resemble in many respects the forces be- tween moving electric charges; in particular unless the two spheres are moving with the same speed and in the same direction the forces between them are not equal and opposite, so that the momentum of the two spheres is not constant. If, however, instead of confining our attention to the spheres we include the water in which they are moving, we find that the spheres plus the water form a system which obeys the ordinary laws of dynamics and whose momentum is con- stant; the momentum lost or gained by the spheres is gained or lost by the water. The case is quite parallel to that of the moving elec- tric charges, and we may infer from it that when we have a system whose momentum does not remain constant, the conclusion we should draw is not that Newton’s third law fails, but that our system, in- stead of being isolated as we had supposed, is connected with another system which can store up the momentum lost by the primary, and that the motion of the complete system is in accordance with the ordinary laws of dynamics. Returning to the case of the electrified bodies we see then that these must be connected with some invisible universe, which we may call the ether, and that this ether must possess mass and be set in motion when the electrified bodies are moved. We are thus surrounded by an invisible universe with which we can get into touch by means of electrified bodies; whether this universe can be set in motion by bodies which are not electrified is a question on which we have as yet no decisive evidence. 236 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Let us for the moment confine ourselves to the case of electrified bodies, the fact that when these move they have to set some of the ether in motion must affect their apparent mass—for exactly the same reason that the apparent mass of a body is greater when it is im- mersed in water than when it is in a vacuum; when we move the body through the water we have to set in motion, not merely the body itself, but also some of the water around it, in some cases the increase in the apparent mass of the body due to this cause may be much greater than the mass of the body itself. This is the case, for example with air bub- bles in water which behave as if their mass were many hundred times the mass of the air inclosed in them. In the case of the electrified bodies we may picture to ourselves that the connection between them and the ether around them is established in the following way, we may suppose that the lines of electric force which proceed from these charged bodies and pass through the ether, grip, as it were, some of the ether and carry it along with them as they move; by means of the laws of electricity we can calculate the mass of ether gripped by these lines in any portion of space through which they pass. The results of this calculation can be expressed in a very simple way. Faraday and Maxwell have taught us to look for the seat of the po- tential energy of an electrified system in the space around the system and not in the system itself, each portion of space possessing an amount of this energy for which Maxwell has given a very simple expression. Now, it is remarkable, that if we calculate the mass of the ether gripped by the lines of electric force in any part of the space surrounding the charged bodies, we find that it is exactly pro- portional to the amount of potential energy in that space, and is given by the rule that if this mass were to move with the velocity of light the kinetic energy it would possess would be equal to the elec- trostatic energy in the portion of space for which we are calculating the mass. Thus, the total mass of the ether gripped by an electrical system is proportional to the electrostatic potential energy of that system. Since the ether is only set in motion by the sideways motion of the lines of force and not by their longitudinal motion, the actual mass of the ether set in motion by the electrified bodies will be some- what less than that given by the preceding rule, except in the special case when all the lines of force are moving at right angles to their length. The slight correction for this slipping of the lines of force through the ether does not affect the general character of the effect, and in what follows I shall for the sake of brevity take the mass of the ether set in motion by an electrified system to be proportional to the potential energy of that system. The electrified body has thus associated with it an ethereal or astral body, which it has to carry along with it as it moves and which increases its apparent mass. Now, this piece of the unseen universe which the charged body carries along MATTER AND ETHER—THOMSON. 237 with it may be expected to have very different properties from ordi- nary matter; it would of course defy chemical analysis and probably would not be subject to gravitational attraction, it is thus a very in- teresting problem to see if we can discover any case in which the ethereal mass is an appreciable fraction of the total mass, and to com- pare the properties of such a body with those of one whose ethereal mass is insignificant. Now in any ordinary electrified system, such as electrified balls or charged Leyden jars the roughest calculation is sufficient to show that the ethereal mass which they possess in virtue of this electrification is absolutely insignificant in comparison with their total mass. Instead, however, of considering bodies of appre- ciable size let us go to the atoms of which these bodies are composed, and suppose, as seems probable, that these are electrical systems and that the forces they exert are electrical in their origin. Then the heat given out when the atoms of different elements combine will be equal to the diminution of the mutual electrostatic potential energy of the atoms combining, and therefore by what we have said will be a measure of the diminution of the ethereal mass attached to the atoms; on this view the diminution in the ethereal mass will be a mass which moving with the velocity of light possesses an amount of kinetic energy equal to the mechanical equivalent of the heat de- veloped by their chemical combination. As an example, let us take the case of the chemical combination which of all those between ordi- nary substances is attended by the greatest evolution of heat, that of hydrogen and oxygen. ‘The combination of hydrogen and oxygen to form 1 gram of water evolves 4,000 calories, or 16.810" ergs, the mass which moving with the velocity of light, i. e., 310" centimeters per second possesses this amount of kinetic energy is 3.7107 grams, and this therefore is the diminution in the ethereal mass which takes place when oxygen and hydrogen combine to form 1 gram of water; as this diminution is only about 1 part in three thousand million of the total mass it is almost beyond the reach of experiment, and we conclude that it is not very promising to try to detect this change in any ordinary case of chemical combination. The case of radio-active substances seems more hopeful, for the amount of heat given out by radium in its transformations is enormously greater weight for weight than that given out by the ordinary chemical elements when they combine. Thus, Professor Rutherford estimates that a gram of radium gives out during its life an amount of energy equal to 6.17 10"* ergs, if this is derived from the electric potential energy of the radium atoms, the atoms in a gram of radium must possess at least this amount of potential energy, they must therefore have associated with them an ethereal mass of between one-eighth and one-seventh of a milligram, for this mass if moving with the velocity of light would have kinetic energy equal to 6.710'* ergs. Hence, we con- 238 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. clude that in each gram of radium at least one-eighth of a milligram, i. e., about 1 part in 8,000, must be in the ether. Considerations of this nature induced me some time ago to make experiments on radium to see if I could get any evidence of part of its mass being of an ab- normal kind. The best test I could think of was to see if the pro- portion between mass and weight was the same for radium as for ordinary substances. If the part of the mass of radium which is in the ether were without weight then a gram of radium would weigh less than a gram of a substance which had not so large a proportion of its mass in the ether. Now, the proportion between mass and weight can be got very accurately by measuring the time of swing of a pendulum; so I constructed a pendulum whose bob was made of radium, set it swinging in a vacuum and determined its time of vibra- tion, to see if this were the same as that of a pendulum of the same length whose bob is made of brass or iron. Unfortunately radium can not be obtained in large quantities, so that the radium pendulum was very light, and did not therefore go on swinging as long as a heavier pendulum would have done; this made very accurate deter- minations of the time of swing impossible, but I was able to show that to about 1 part in 3,000 the time of swing of a radium pendulum was the same as that of a pendulum of the same size and shape made of brass or iron. The minimum difference we should expect from theory is 1 part in 8,000, so that this experiment shows that if there is any abnormality in the ratio of the mass to weight for radium it does not much exceed that calqilated from the amount of heat given out by the radium during its transformation. With larger pendulums the value of the ratio of mass to weight can be determined with far greater accuracy than 1 part in 8,000; for example, Bessel three-quar- ters of a century ago showed that this ratio was the same for ivory as for brass to an accuracy of at least 1 part in 100,000; and with appa- ratus specially designed to test this point an even greater accuracy could be obtained. When I made my experiments with the radium pendulum the close connection between the amounts of uranium and radium in radio-active minerals had not been discovered; this con- nection makes it exceedingly probable that radium is derived from uranium and that this metal may have weight for weight more elec- tric potential energy, and therefore a larger proportion of its mass in the ether, than radium itself. This points to the conclusion that the proper substance to use for the pendulum experiment is uranium rather than radium, especially since uranium can easily be obtained in sufficiently large quantities to enable us to construct the pendulum of the shape and size which would give the most accurate results, it would not, I think, be impossible to determine the ratio of mass to weight for uranium to an accuracy of 1 part in 250,000. MATTER AND ETHER—THOMSON. 239 Though we have not been able to get direct experimental evidence of the existence of the part of the mass in the ether in this way, we are in a more fortunate position in respect to a closely allied phe- nomenon, viz, the effect of the speed of a body on its apparent mass. We have seen that the mass of the ether bound by any electrical system is proportional to the electric potential energy of that system. Now let us take the simplest electrical system we can find—a charge of electricity concentrated on a small sphere. When the sphere is at rest the lines of electric force are uniformly distributed in all direc- tions round the sphere. When the lines are arranged in this way the electric potential energy is smaller than for any other possible distribution of the lines. Now, let us suppose that the sphere is set in rapid motion, the lines of electric force have a tendency to set themselves at right angles to the direction in which they are moving; they thus tend to leave the front and rear of the sphere and crowd into the middle. The electrical potential energy is increased by this process, and since the mass of the ether bound by the lines of electric force is proportional to this energy, this mass will be greater than when the sphere was at rest. The difference is very small unless the velocity of the spheres approaches the velocity of light, but when it does so the augmentation of mass is very large. Naufman has suc- ceeded in demonstrating the existence of this effect for the B particles emitted by radium; these are negatively electrified particles projected at high speeds from the radium; the velocity of the fastest is only a few per cent less than the velocity of light; along with these there are others moving much less rapidly. Kaufman determined the masses of the different particles, and found that the greater the speed the greater the mass, the mass of the more rapidly moving particles being as much as three times that of the slower ones. These experi- ments also led to the very interesting result that the whole of the mass of these particles is due to the charge of electricity they carry. On the view we have been discussing this means that the whole of the mass of these particles is due to the ether gripped by their lines of force. If lines of electric force grip the ether,-then, since waves of light, according to the electromagnetic theory of light, are waves of electric force traveling at the rate of 180,000 miles per second, and as the lines of electric force carry with them some of the ether, a wave of light will be accompanied by the motion of a portion of the ether in the direction in which the light is traveling. The amount of this mass can be easily calculated by the rule that it would possess, if traveling with the velocity of light, an amount of kinetic energy equal to the electrostatic potential energy in the light; as the electro- static energy is one-half the energy in the light wave, it follows that the mass of the moving ether per unit volume is equal to the energy 240 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. of the light in that volume divided by the square of the velocity of light. Thus, when a body is radiating a portion of the mass of the ether gripped by the body is carried out by the radiation. This mass is, in general, exceedingly small. For example, we find by the appli- cation of the rule we have just given that the mass emitted by each square centimeter of surface of a body at the temperature of the sun is only about 1 milligram per year. We should expect that when some of the ether, bound to a body by its lines of force, is carried off by the radiation, other portions of ether which will not be connected with the body will flow in to take its place. Thus, in consequence of the radiation which proceeds from all bodies, the ether around them will be set in motion in much the same way as if a series of sources and sinks were distributed throughout the bodies. Though the actual mass of the ether traveling with a wave of light is exceedingly small, yet its velocity is so great, being that. of light, that even a very small mass possesses an appreciable amount of momentum. When the light is absorbed in its passage through a medium which is not perfectly transparent this momentum will also be absorbed and will be communicated to the medium, and will tend to make it move in the direction in which the light is traveling; the hght will thus appear to exert a pressure on the medium; the pressure, which is called the pressure of radiation, has been detected and measured by Lebedew, Nicols and Hull, and Poynting. All the phenomena associated with this pressure may be explained very simply by the view that light possesses momentum in the direction in which it is traveling. The possession of momentum by light, supposing light to be an electric phenomenon, has been deduced by somewhat abstruse consideration. On the old Newtonian emission theory it is obvious at once that this momentum must exist, for it is Just the momentum of the particles which constitute the light. It is remarkable how recent investigations have shown that many of the properties of light which might be supposed to be peculiar to a process similar to that contemplated on the emission theory would also be possessed by the light if it were an electric phenomenon. There is one consequence of the emission theory to which I should like briefly to allude, because I think it is more in accordance with the actual properties of light than the view to which we should be led if we took the electro-magnetic theory in the form in which it is usually presented. The active agents on the emission theory are discrete particles, a ray of light consisting of a swarm of such par- ticles, the volume occupied by these particles being only a very small fraction of the volume through which they are distributed. The front of a wave of light would on this view consist of a multitude of small bright specks spread over a dark ground; the wave front in fact is porous and has a structure. Now on the electric theory MATTER AND ETHER—THOMSON. 241 of light as usually given, it is tacitly assumed that the electric force is everywhere uniform over the wave front, that there are no vacant spaces, and that the front has no structure. This is no necessary part of the electric theory, and I think there is evidence that the wave front does in reality much more closely resemble a number of bright specks on a dark ground than a uniformly illuminated area. Let me mention one such piece of evidence. If a flash of light, espe- cially ultra-violet light, fall on a metal surface, negatively electrified corpuscles are emitted from the surface; but when we measure, as we can do, the number of these, we find that only a most insignifi- cant fraction of the number of molecules passed over by the wave front have emitted these corpuscles. If the wave front were continu- ous, then all the molecules of the metal exposed to the hght would be under the same condition, and although, like the molecules of a gas, the molecules might possess very different amounts of kinetic energy, this difference would be nothing like sufficient to account for the enormous discrepancy between the number of molecules struck by the light and those which emit corpuscles. This discrepancy would, however, easily be understood if we suppose that the wave front is not continuous but full of holes, so that only a small number of molecules come under the influence of the electric force in the light. We may suppose that light consists of small transverse pulses and waves traveling along discrete lines of electric force, dissemi- nated throughout the ether, and that the diminution in the intensity of the light as it travels outward from a source is due not so much to the enfeeblement of the individual pulses as to their wider separation from each other, just as on the emission theory the energy of the individual particles does not decrease as the light spreads out; the diminution of the intensity of the light is produced by the spreading out of the particles. The idea that bodies are connected by lines of electric force with invisible masses of ether has an important bearing on our views as to the origin of force and the nature of potential energy. In the ordi- nary methods of dynamics a system is regarded as possessing kinetic energy which depends solely upon the velocities of the various parts of which it is composed, and potential energy depending on the rela- tive position of its parts. The potential energy may be of various kinds; thus we may have potential energy due to gravity and poten- tial energy due to stretched springs, or electrified systems, and we have rules by which we can calculate the value of these potential energies corresponding to any position of the system. When we know the value of the potential energy the method known as that of “ La- grange’s equations” enables us to determine the behavior of the sys- tem. As a means of calculation and investigation this use of the 242 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. potential energy works admirably, and is very unlikely to be super- seded; but, regarded from a philosophical point of view, the concep- tion of potential energy is much less satisfactory and stands on quite a different footing from that of kinetic energy. When we recognize energy as kinetic we feel that we know a great deal about it; when we describe energy as potential we feel that we know very little about it, and though it may be objected that from a practical point of view that little is all that is worth knowing, the answer does not satisfy an inquisitive thing like the human mind. Let us consider a commercial analogy and compare kinetic energy to money in actual cash and potential energy to money at our credit in a bank, and suppose such a state of things to exist that when a man lost a sovereign from his pocket it was invariably collected, he did not know how, and placed to his credit in a bank situated he knew not where, from which it could always be recovered without loss or gain. Though the knowledge that this was so might be sufficient for all commercial purposes, yet one could hardly suppose that even the most utilitarian and matter-of-fact of men could refrain from specu- lating as to where his money was when it was not in his pocket, and endeavoring to penetrate the mystery which envelops the transfer of the sovereign backward and forward. Well, so it is with the physicist and the conception of different forms of potential energy ; he feels that these conceptions are not simple, and he asks himself the question whether it is necessary to suppose that these forms of energy are all different; may not all energy be of one kind—kinetic? and may not the transformation of kinetic energy into the different kinds of potential energy merely be the transfer of kinetic energy from a part of the system which affects our senses to another which does not, so that what we call potential energy is really the kinetic energy of parts of the ether which are in kinematical connection with the material system? Let me illustrate this by a simple example. Suppose I take a body, A, and project it in a region where it is not acted on by any force. A will move uniformly in a straight line. Suppose, now, I fasten another body, B, to it by a rigid connection, and again project it. A will not now move in a straight line, nor will its velocity be uniform; it may, on the contrary, describe a great variety of curves, circles, trochoids, and so on, the curves depending on the mass and velocity of B when A was projected. Now, if B and its connection with A were invisible so that all we could observe was the motion of A, we should ascribe the deviation of A’s path from a straight line to the action of a force, and the changes in its kinetic energy to changes in the potential energy of A as it moved from place to place. This method is, however, the result of our regarding A as the sole member of the system under observation, whereas A is in reality only a part of a larger system; when we consider the sys- MATTER AND ETHER—THOMSON. 948 tem as a whole we see that it behaves as if it were free from the action of external forces and that its kinetic energy remains constant; what on our restricted view we regarded as the potential energy of A is seen on the more general view to be the kinetic energy of the system B. It is now many years ago since I showed that the effects of force and the existence of potential energy may be regarded as due to the connection of the primary system with second- ary systems, the kinetic energy of these systems E being the potential energy of the primary, the complete system having no energy other than A the kinetic energy of its constituents; a similar view is the foundation of Hertz’s system of mechanics. Let us consider one or two simple mechanical systems in which the motion of matter attached ¢ D to the system produces the same effect as a force. Suppose A and B (fig. 1) are two bodies attached to tubes which can slide verti- eally up and down the rod E F, and that two balls C and D are attached to A and B by rods B hinged at A and B, then if the balls rotate about the rod they will tend to.fly apart, and as F Bane tt the balls move farther from the rod their points oe of attachment A and B must approach each other; thus A and B will tend to move toward each other, i. e., they will behave as if there were an attractive force acting between; the velocities of A and B, and therefore their kinetic. energy, will change from time to time; the kinetic energy lost by A and B will really have gone to increase the kinetic energy of the balls. If the rotating system C and D had been invisible we should have explained the behavior of the system by assuming an at- tractive force with corre- sponding potential energy be- tween A and B. This is due to our considering A and B as a complete system, whereas it is in reality part of a larger system, and when we consider the complete system we see that it behaves as if it were acted on by no forces and possessed no energy other than kinetic. It may perhaps be of interest to note that we can in a similar way make two bodies appear to attract each other with a force varying inversely as the square of the distance between them. Let A and B (fig. 2) be the bodies, and suppose that parabolic wires without mass Hig. 2: 244 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. are fixed to them, if these are threaded through a ring P with a small but finite mass and the system caused to rotate round A and B, the effort of the ring to get away from the axis of rotation will cause A and B to approach each other, and the law of approach may easily be shown to be the same as if there was a force between them vary- ing inversely as the square of the distance. The result mentioned on page 236 that the potential energy of a system charged with electricity is equal to the kinetic energy of the mass of ether bound to the system when moving with the velocity of light is another example of potential energy, being in reality the kinetic energy of an associated system, and indeed, as I have endeav- ored to bring before you this evening, the study of the problems brought before us by recent investigations leads us to the conclusion that ordinary material systems must be connected with invisible systems which possess mass whenever the material systems contain electrical charges. If we regard all matter as satisfying the condi- tion we are led to the conclusion that the invisible universe—the ether—is to a large extent the workshop of the material universe, and that the phenomena of nature as we see them are fabrics woven in the looms of this unseen universe. DEVELOPMENT OF GENERAL AND PHYSICAL CHEM- ISTRY DURING THE LAST FORTY YEARS. By W. NERNST. Although in principle physics and chemistry follow the same methods and look toward a common end, an end which, as Helm- holtz has so aptly described it for physics, is “To assert by the logical forms of laws our intellectual mastery over nature, at first a stranger to us,” nevertheless the diversity of the problems and facilities has in practice necessitated a separation of the two branches. Consequently the energies of the physicist and chemist have been expended almost entirely on special problems in their own fields of research, and as a result a large boundary region between the two sciences remained neglected for a long time. Only in the period of time which this sketch covers has there been any lively interest in physical and theoretical chemistry. No one will deny that, as far as any theoretical mastery of matter is concerned, physics has not for a long time made nor is even now making any advances. Why this can not be otherwise is easy to un- derstand. The physicist often needs relatively only a very small amount of material to work on to derive immediately the fundamental theoretical laws of the subject which he is investigating. For example, it is only necessary to know the density of atmospheric air at a single temperature and a single pressure to develop physico-mathematically by the sole aid of the gas laws and the principles of the theory of heat the rule of sound vibration, and from that the fundamental prin- ciples of acoustics generally. How different and how much more difficult are the problems which confront the chemist when he at- tacks the study of atmospheric air, whether he attempts to determine its composition down to the last particle or whether he investi- gates the remarkable and complex equilibria which obtain at high temperatures. Chemistry to-day can boast of a set of theoretical principles that do not suffer in comparison with those of physics. What a mass of @ Address before the German Chemical Society at the celebration of the for- tieth anniversary of the society, November 11, 1907. Translated, by permission, from Berichten der Deutschen Chemischen Gesellschaft, Jahrgang XXXX, Heft 17. Berlin, 1907, pp. 4617-4626. 245 246 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. experimental material is set forth in the table of atomic weights. What quantitative facts can the man of science draw forth from its figures, such as composition, specific heat, vapor density, lowering of the freezing point, and the like of innumerable substances. What can he not forecast, by the aid of general analogy, in the way of physical and chemical properties of many other kinds when he calls to his aid that happy artifice, the periodic classification. The very fact that such an abundance of material has been brought together necessarily increases many times its importance after it has once been successfully classified. The theory of the constitution of organic combinations furnishes a good example of this fact. In a short time, when the organic com- pounds gathered together in the new edition of Beilstein’s hand- book which this society has under preparation are published, we shall, I have been told by the editor, be confronted by more than a hundred thousand structural formule. It is by the aid of this theory of organic constitution that a great part of these combinations have been worked out, and it is only by its aid that it has been possible to describe and classify this stupendous amount of material. And if one finally considers all the information the initiated can read out of the structural formulas and considers the mass of experimental data that often had to be obtained to establish even one of them, he realizes that in the quantity of experimental facts logically construed and classified, the doctrine of the constitution of organic combina- tions stands at the head of all theories that the human mind has conceived. Another effect of the development of chemistry from the theoretical point of view is that already in a great many cases theoretical and experimental work can hardly be distinguished, so impregnated with theory have most of the branches of chemistry become. Consequently, it is my task to-day to give not a general view of the whole of theo- retical chemistry, but merely of that part which may be called physical. In the first part of this sketch the relations between physical prop- erties and chemical constitution will be touched on, a subject which formed the principal field of research for physico-chemical work in the latter half of the period we are considering. The description of this work will be very much facilitated by an adherence to a system- atic mode of classification, according to which the properties of sub- stances are divided into three groups. There is, first, the measurement of those accessible quantities which render possible the immediate deduction of the values for the molecu- lar weights, and which may be briefly designated as molar properties. Among these, as Avogadro has shown, the vapor density deserves a GENERAL AND PHYSICAL CHEMISTRY—NERNST. 247 place in the first rank, but it has been left for the new epoch, by the aid of the direct and indirect methods of measuring osmotic pressure, to throw an equal light on the molecular weight of dissolved sub- stances. In the determination of the molecular weight of liquids the value of the temperature coefficient of surface tension has been of the greatest assistance; the heat of vaporization, the critical con- stants, the curves of vapor tension, and a series of other values, also furnish more or less sure means to the same end. All these methods, with complete accord, lead to the conclusion that most substances, for instance the saturated hydrocarbons, pos- sess the same molecular weight in the liquid state as in the gaseous condition, but that a number of substances, like the alcohols and especially water, are more or less highly polymerized in the liquid condition. But what is the degree of polymerization in each particu- lar case? What equilibrium is established in these pure liquids? These interesting questions unfortunately still evade any exact or quantitative solution. As the most important results of these new methods of determin- ing molecular weights, especially of the Osmotic method, we may mention first the ingenious theory of the existence of colloidal solu- tions as an intermediate stage between true solutions and mechanical suspensions, and then the more definite conception of the ion to which we shall return later. A second series of properties are those designated under the name of additive properties. Any such property of a combination is the resultant sum of the properties of its constituents. To all appear- ances this is a very simple rule, but at the same time it is impossible to form any idea from it as to the size and structure of the molecule. Among these properties we may note, beside the molecular volumes of liquid organic compounds, molecular refraction, magnetic rota- tion, heat of combustion and the critical coefficient. A third series of properties depends not only on the nature of the atoms which exist in the molecule, but also on their arrangement in the molecular structure; accordingly they are designated constitutive properties. Thus the molecular refraction of hydrocarbons depends not only on the number of hydrogen and carbon atoms present, but also on the existence or nonexistence of multiple bonds between the carbon atoms. From this we derive a very important result; we may attribute to the double bond a determinate amount of refraction and take into account with a high degree of approximation, the influence of its constitution, by a return to the additive method. Frequently certain properties appear only with a particular group- ing of atoms. In such case it is a qualitative rule of the highest 88292—sm 1908——17 248 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. value that, inversely, from the appearance of these properties we can predicate the existence of these definite forms of combination. The classic example of this type is afforded by the power of optical rota- tion in carbon compounds, which is dependent on the existence of one or more asymmetric carbon atoms (or similar asymmetric struc- tures) in the molecule. In the same way in these organic compounds one can discover from the appearance of color, or more exactly, from the appearance of certain characteristic absorption bands, as well as of fluorescence the existence of particular groupings in the molecule. To this same category of properties belongs also, in the largest sense, electrolytic conductivity, which indicates the existence of free ions—that is to say, the combination of elements or radicles with electrons; and lastly, the appearance of the maximum value of 5:3 for the ratio of the spe- cific heats of a gas is, according to the kinetic theory of gases, an indication of a monoatomic state, a conclusion which, as is generally known, was first applied to mercury vapor, and which in recent times has been of inestimable service in the determination of the atomic weights of the argon group of elements. In the last analysis all these properties are probably constitutive also, and their interpretation as either purely molar or purely additive is only a more or less close approximation. Often, even in the regions which have already been cleared up to a great extent by the additive method, great difficulties have appeared upon a more careful investi- gation. I should like, therefore, all the more to place before you a special case where the theory seems to have reached the greatest exactitude. We have succeeded in reducing to exact terms the gas densities which for a long time afforded the only means of molecular weight determination. On account of the variation from the laws of per- fect gases, which all actual gases show, it was natural that a method of approximation should be developed. In our epoch, however, we have learned with the help of van der Waals’ equation, particularly by using compressibility, to reduce all gases to the ideal gaseous state and thence to deduce the exact relative values of molecular weights. From these results, two ends have been attained: First, it has been proved that the most important of the theoretical laws that we possess, Avogadro’s rule, appears to be an infinitely exact natural law; and second, a new method, purely physical, of determining atomic weights has been acquired which can stand comparison in exactness with the methods of analytical chemistry, but which is limited natu- rally to the cases where the density and compressibility of a chem- ically pure gas can be determined. GENERAL AND PHYSICAL CHEMISTRY—NERNST. 249 The problem, however, of reconciling experience and theory in the case of some other physical properties, as successfully as in this example, seems still far from solution. In general the exactness and consequently the reliability of theoretical treatment have been more striking in connection with the theory of corresponding states which we shall now take up. In the theoretical consideration of natural processes, it has gener- — ally been considered necessary to take account only of very small variations of the system under observation; a variation of any extent caused so many complex accessory phenomena that it was impossible for the mind’s eye to follow them. Thus in theoretical physics we see the quintessence of nearly all theories represented by a differential equation, that is to say, by a mathematical formula which has to do with only infinitely small variations. The establishment of a differ- ential equation (assuming, of course, that it can be solved) has a symtomatic signification in a science, since its employment proves that the region of corresponding phenomena has been carefully con- sidered. It was, however, by a rare and fortunate chance that the law of mass action was established in chemistry some forty years ago. I recall very vividly the great surprise I experienced when for the first time a differential equation appeared to me in the study of the speed of reaction of the saponification of ethers, especially when I discovered how beautifully the integral of this equation was confirmed by the facts. How many inconsistencies, how many irregularities, and how many values depending on all sorts of condi- tions appear at first glance in chemical phenomena! Nevertheless the law of mass action shows us that, if we disregard the secondary phenomena of supersaturation and the like, if we maintain a constant temperature, and if we consider a chemically homogeneous system, we will have to deal with phenomena very clearly defined and calcu- lable with mathematical precision. The law of mass action furnishes at the same time the law for static and kinetic chemistry. It gives us the outlines not only for the experimental investigation of chemical equilibrium but for the speed of chemical reaction. Therefore I can cite as the most im- portant result of the last forty years in this field the fact that not only are we in possession of the laws of chemical equilibrium and the speed of reaction, but above all we can classify a great many experimental facts as logically following the law of mass action. This law, as I have stated, is of the most general application, but experience shows us that general theories are not very profitable. Accurate results are never obtained except by fortunate specialization. Organic chemistry, characterized by the inertia of the bonding of the carbon atom, furnishes a vast field for the application of kinetic chemistry, while the solutions of salts, acids, and bases which are 250 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. characterized by the practically instantaneous nature of a certain category of chemical reactions offer an almost inexhaustible series of chemical equilibria. Here, however, the law of electrolytic dissociation comes to our aid, a law derived, it is true, in principle from experiments on the electric _ conductibility of dilute saline solutions, but which was first put on a reliable experimental footing by the osmotic method of molecular weight determination. The importance of this doctrine extends far beyond the field of chemistry proper. Briefly described, its application to chemical proc- esses consists in the fact that it allows an exact application of the laws of static chemistry to characteristic aqueous solutions and through these to the reactions of ordinary analytic chemistry. The later refinement of this doctrine has resulted in a very detailed theory of equilibrium in dilute solutions, and in particular in the proof of the fact that when, for a certain solvent, the coefficients of dissociation and solubility of those electrically neutral molecules which are composed of several combined ions are known, the equi- librium in this solvent can be calculated, and if the coefficients of distribution are known, the equilibrium in any other solvent what- ever can be derived with equal facility. On account of the simplicity of the gaseous state we should expect that the law of mass action would be particularly profitable in reference to this phase. But it was found that at low tempera- tures the speeds of reactions, like many of the reactions of organic chemistry, were generally very small. At high temperatures, how- ever, equilibrium was established as in ionic reactions almost instan- taneously. But in this simple field there are, at the lower tempera- tures, difficultly controlled catalytic influences, and at the high temperatures inherent experimental difficulties place themselves in the way. It is nevertheless to be hoped that in this field of gaseous reactions which investigators are now eagerly attacking from differ- ent points, a wealth of material and a corresponding theoretical profit will soon be forthcoming. In the application of thermodynamics to chemical phenomena lies another field where the methods of theoretical physics have been fruitful. There, too, the first great step in advance was taken almost forty years ago. The work I allude to is that particularly important proof that the chemical law of mass action should be recognized as a direct application of thermodynamics, which is found in volume 2 of the transactions of the German Chemical Society. Among the further results obtained in this way I should state that the aid of thermodynamics alone has made possible the close and ex- haustive study of heterogeneous equilibria, particularly those where mixtures of given concentration (not only dilute solutions) enter into GENERAL AND PHYSICAL CHEMISTRY—NERNST. aad f the equilibrium. For special cases of heterogeneous equilibria there comes into play the so-called “ phase rule,” which expresses in prin- ciple that in every case fixed (stable) equilibria correspond to given conditions of temperature, pressure, and concentration. This rule is therefore rather a reliable formula than a theory proper, and that is why from many sides we are warned not to exaggerate its value. More important from a theoretical standpoint is the demonstration in chemical compounds of two sorts of stability. One is the apparent stability which is characterized by the fact that its speed of decom- position is very slow (examples: Nitric oxide, hydrogen peroxide, and most organic compounds), and the other, the true stability, which is characterized by the ‘fact that the equilibrium depends on a quantita- tive formation of the substance considered apart from its components. Electrochemistry and photochemistry are governed by laws closely related to those of thermochemistry. Although the study of the latter of these two fields has presented, up to the present time, great difficulties in the way of theoretical investigation, Faraday’s law, which establishes the proportion between chemical transformation and the quantity of electricity passed through a system in a given time and which thus makes possible the calculation of the electric energy necessary for a given change, has provided an accurate foundation for the application of thermodynamics to electrochemistry. Also, by continuing the special conception which gave rise to the theories of osmotic pressure and electrolytic dissociation, a simple conception of electrochemical processes has been developed. It has at the same time become apparent that electrical forces unquestionably play a great part, not only in electrochemical phenomena, but also in many purely chemical reactions. Thus we are brought to the problem of the nature of chemical forces. Although this question does not perhaps possess the funda- mental importance that is often attributed to it, nevertheless it should be briefly considered. It can be treated here still more briefly be- cause we are obliged to admit that during the period under considera- tion there has been no answer to this question which really tells us anything more than we can see with our own eyes. It seems reason- ably certain that we should admit the existence, not only of electrical and therefore polar forces, but of nonpolar natural forces somewhat of the nature of Newtonian gravity. When fluorine and potassium unite to form a salt, the colossal affinity between the two elements de- pends at any rate in part on the affinity of the fluorine for negative electricity and of the potassium for positive electricity ; but when we find in the ordinary nitrogen molecule two atoms of nitrogen united in a combination, perhaps of equal stability, it would appear that in the case of as complete an identity as presented by two atoms of nitrogen the action of polar forces should be entirely excluded. The 252 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. fact that polar and nonpolar forces always act simultaneously in the production of chemical combinations is the principal reason why in- vestigators have not yet been able to fathom the nature and the law of chemical forces, and is responsible for the fact that the investiga- tions have not yet gotten away from a consideration of the balance of energy. There is no need of entering here into that mooted question which has been brought up many times in physical chemistry, the question of the supremacy of the thermodynamic or the atomistic theory. This is perhaps nearly as important as determining whether Schiller or Goethe was the greater man, and should be answered in a like manner: We should rejoice in the possession of two resources so powerful and at the present time so indispensable for scientific thought. The chronicler should, however, make note of the fact that most of the modern results in the domain of physical chemistry have been obtained by a happy combination of thermodynamic methods with molecular theories, such as the creators of the modern theory of heat have followed in devoting most of their work to the development of the atomistic side, particularly of the kinetic theory. Thermodynamics had its origin in the methods of mathematical physics. The atomic theory, on the contrary, owes its high state of perfection especially to chemical research. We should regard as a result of the latter the application of the atomic theory to the science of electricity which has begun to develop a chemical theory of elec- tricity. There are many reasons for believing that the two forms of electricity are composed of almost infinitely small particles, each identical with the other, called “ electrons.” Consequently, free ions should be interpreted as combinations between the elements or radicles and the electrons, to which the laws of constant and multiple propor- tions apply and which likewise are governed by the theory of valence. We must limit, however, this brief indication of how the atomic theory by such a marvelous enlargement of its horizon, has put a number of physical and chemical processes in an entirely new light, and end with a few words on the radio-active emanations whose existence is made clear to us through the electron theory. The effects of this radiation, according to the prevailing theory, are caused by the projection of electrons either in a free state or bound up with matter, and whose existence is most easily determined by the electroscope. These very recent researches have opened to us the new world of radio-active substances. For sensitiveness this method of research is often superior even to spectral analysis. As an example I may mention the fact that according to the calculations of a young investigator in this field, if a milligram of radium C were divided among all the people living on the earth (about two thousand millions) each one of them would possess an amount suflicient to dis- GENERAL AND PHYSICAL CHEMISTRY—NERNST. 253 charge five electroscopes, sufficient to enable him to study (with a sufficient experimental accuracy) the most important radio-active properties of each element. The extreme sensitiveness of this reagent for radio-active substances has been the only factor which has permitted the discovery of several radio-active elements which had heretofore escaped notice because of their very small quantity or because of the brief period of their exist- ence (in the sense of the hypothesis of atomic decomposition). It is often easy to write history, but it is always more difficult to learn anything from the history after it is written. If I dare make a modest attempt in this direction, I should say perhaps that the chemist with such a mass of material to work on is destined in the future to prepare new compounds and to study the reactions of those already known as in the past, but that the methods of experimental and theoretical physics will be more and more called into requisition to supplement purely chemical research. Bhs ae 0 ae A, hh DEVELOPMENT OF TECHNOLOGICAL CHEMISTRY DURING THE LAST FORTY YEARS.¢ By O. N. WIrTt, Professor of Technical Chemistry at the Polytechnic School of Charlottenburg. The representatives of chemistry, general and physical, inorganic and organic, have striven in noble emulation to surpass each other in the number and importance of their discoveries. From the labora- tories great and small, official and private, the results of research have flowed like the rivulets which, irrigating the well-watered fields, come together in brooks, then in streams and in rivers, bringing fertility to the habitations of men in the valleys. An abundant harvest has been raised on these watered plains, a harvest which has been enthusiastically consumed by the people. This harvest, the reward of scientific research, the abundant fruit of the patient work of the mind, consists of the applications which contribute to the well-being of the people. This is why technical chemistry is the worthy companion of abstract research in our science. It should prosper when research is flourishing, and the additions to chemical technique, during the last forty years, are a striking proof of the correctness of this assertion. About the time when the German Chemical Society was founded a period of far-reaching transformation began in industrial chem- istry. The industry of mineral acids and alkalis, based on the Le- blanc process—the only one which could boast at that time of the title “great chemical industry ”—still adhered to its stereotyped operations and to the dependency of its series of steps, one upon the other. But the young Titan which was destined to struggle with and cause its complete rehabilitation—the Solvay process for the produc- tion of soda by means of ammonia—had come into existence and was already developing. About 1870 this process appeared to have “Address before the German Chemical Society at the celebration of the for- tieth anniversary of the society, November 11, 1907. Translated by permission from Berichten der Deutschen Chemischen Gesellschaft, Jahrgang XXXX. Heft 17. Berlin, 1907, pp. 4644-4652. 256 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. reached a productive stage, and it was recognized that the possibility of obtaining soda independently of the Leblanc process would break up the whole continuity of this great chemical industry. It was still protected, however, by the close dependence on it of the production of hydrochloric acid and from this the making of chlorine by the sulphate process, and by the advantages offered by the soluble product of its raw soda in the preparation of caustic soda. In truth, these two circumstances prolonged the life of the Leblanc process for sev- eral decades and are responsible for the fact that even yet it has not entirely disappeared. Toward 1860, almost simultaneously with the development of a commercial process for the production of soda by ammonia, came the inauguration of the potash industry at Stassfurt, which was founded on the fortunate discovery of the deposits of salts there, under the fertile influence of Liebig’s wonderful researches. To the preparation of potassium chloride from carnallite and sylvinite soon was added the preparation of bromine, of potassium nitrate by the use of sodium nitrate, and the manufacture of potash by the Leblane process, without any danger here of a concurrent process with ammonia. Finally, a successful process was developed for the utilization of part at least of the magnesium compounds which were present in the salt deposits, although the successful extraction of all the magnesium chloride made in the potassium industry is to-day still in the category of unsolved problems. The year 1870 saw the rejuvenation of the century-old industry of oil of vitriol, the fuming sulphuric acid, whose small content of sulphuric anhydride no longer sufficed for modern needs. Tn place of the product obtained by distilling vitriolic schists came synthetic sulphuric anhydride, prepared by the catalytic combination of sulphurous anhydride and oxygen, and the pyrosulphuric acids. This new process of manufacture was to influence and transform the whole sulphuric acid industry to a great extent. It was possible to apply it to advantage more than a quarter of a century later, when the modern contact processes appeared. The last two decades of the nineteenth century were characterized by the development and application with exceptional rapidity of elec- tro-technics. In the field of chemistry, this new phase of industry voiced itself in the development of electrolytic methods of operation. In the field of electro-metallurgical processes, the most important of which are the preparation of aluminum and the electrolytic refining of copper, which are closely followed by the manufacture of calcium carbide and carborundum, the question of the electrolytic decomposi- tion of alkaline chlorides has been a most warmly discussed problem. The difficult problem of preparing membranes which are more sensi- tive, and at the same time more resistant, was solved almost simul- TECHNOLOGICAL CHEMISTRY—WITT. DAY taneously by three processes, that of Griesheim, that of Castner- Keller, and that of Aussig, which are close rivals in their effective- ness and boldness of invention. With these a new era has begun in the production of caustic alkalis, and also in the chlorine industry. The old process for the production of chlorine has disappeared along with the ingenious methods of Weldon and Deacon. Chlorine, once so costly, is produced in such abundance as to provoke a feverish search for new applications for it. By the side of and often in the place of the venerable chloride of lime we find to-day liquefied molec- ular chlorine put up in transportable form in steel bottles. Finally, the production of alkali metals on a large scale should be counted as one of the most important results of modern electro-chem- ical technology. The same reaction in a form suitable to technical methods which once in Davy’s hands led to the discovery of these metals—the electrolysis of alkaline hydrates—has shown itself to be the best and least costly method of manufacture for these strongly reactive bodies, one of which especially, sodium, has rapidly become of extensive application in a technical way. By its aid in particular, it has been possible to produce potassium cyanide free from cyan- ates, which has contributed to the success of the cyanide process for refractory gold ores. Such a metamorphosis of inorganic chemical technology as has been briefly described would not have been conceivable if greater and greater quantities with their continually decreasing prices had not found a continually increasing market. The same fact along with the natural increase of needs generally has produced in the case of organic chemistry an even more striking and remarkable transforma- tion and development than in inorganic technical processes. We all know in a general way that the old industries of brewing, distilling, sugar making, and starch making, of the production of fatty bodies and of foods, all of which are connected with agricul- tural work, have flourished remarkably in the last forty years and have become of very great importance. They owe their most im- portant progress to the aid of modern biological research. But be- sides these, other industries operating on organic substances have sprung up and prospered, which were formerly entirely unknown. A lively interest attaches to the chemical application of wood which has not only allowed a particularly profitable use of our forests, which is coming more and more into evidence, but has also led to a simple separation, almost analytical in its nature and carried out on a large scale, of the components of lignine, one of which, how- ever, the incrusting medium, remains to this day a chemical enigma. The extraction of an almost pure cellulose from wood has placed the paper industry on a new footing and has obviated the necessity of our limiting the production of printed matter for want of paper. 258 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Tt has led also to the discovery of a number of other useful applica- tions of cellulose, of which I will mention only the preparation by various methods of new artificial textile fibers analogous to silk. Wood can be worked chemically, however, in another way than by the separation of its content of cellulose. I refer to the process of dry distillation. The very primitive preparation of carbon and wood tar of the old days has developed during the last forty years into the very highly perfected art of wood distillation, which has obtained most important commercial results with decomposition products formerly entirely neglected—methyl alcohol, acetone, and acetic acid. The attempts, first without result, but later crowned with success, to free the ligneous acetic acid from. the empyreumatic bodies obtained with it have resulted in the fact that the greater parts of our demands for acetic acid are now supplied by the dis- tillation of wood. This industry received a still further impetus in 1890 by the introduction of a process for the preparation from methyl alcohol of formaldehyde, the production of which has enor- mously extended since the extraordinary variety of uses to which this new product can be put has been recognized. Another remarkable method for the treatment of wood, fusing it with alkali for the production of oxalic acid, has not developed, but rather has diminished, in importance during the forty years under consideration. It has been replaced by the synthetic method of preparing this acid, as well as of formic acid, by means of carbon monoxide contained in generator gases. Formic acid can be pre- pared so advantageously in this way that it is competing with acetic acid in many of its applications. The commercial utilization of hydrocarbons of the methane series is brought out in two industries—the distillation of lignites and the refining of petroleum. Both of these industries have shown an ex- traordinary increase in their extent and have displayed numerous marked improvements in their production. Among the latter the desulphurization of fetid petroleum of the Ohio type by distillation over copper oxide should be considered a technical achievement of high rank. The development of coal distillation and the treatment of tar affords a particularly important and interesting example of prog- ress. When this society was founded only one form of distillation of coal was-recognized—its application to the manufacture of illumi- nating gas, which dates from the end of the eighteenth century. This distillation was carried on at a low temperature and furnished the entire amount of tar produced, the tar which is so important in the recently developed color industry. In 1880 the output of tar began to be less abundant, a fact caused not only by the constant increase in its use in the production of tar dyes, but also to a great TECHNOLOGICAL CHEMISTRY—WITT. 259 extent by the far-reaching transformation of the gas industry, which, on account of extended and ingeniously interpreted experiments had been developed into an entirely new process, characterized by the employment of high temperatures of distillation. The momentary embarrassment which fell on the dye industry led to the creation, far-reaching in its consequences, of a new industry—distillation for coke, which saves from destruction the riches contained in the by- products of coke manufacture and which frees for a long time the dye industry from any lack of raw materials. Among the products derived from coal tar may be mentioned anthracene, carbazol, the xylenes and the cresols, coumarone and pyridine, substances whose systematic manufacture is only forty years old and which have found a steady commercial application. Of many of the other of the tar derivatives, some have been only recently discovered, while others have been rendered more available than heretofore. It is to the improvement in its methods of operation, especially in the apparatus, that the industry of tar distillation owes the thorough- ness with which its products may be separated from such a complex mixture as goes to make up tar. Column stills, filter presses, and processes such as vacuum distillation are the means which have enabled the modern tar industry to attain its present position. The most striking example of an industry working hand in hand with scientific research, profitably applying all its results and in- fluencing them in its turn, is afforded by the manufacture of coal-tar colors. It is almost impossible to touch in these few words on the most important stages of the triumphal progress of this industry. We may say that the foundation of the German Chemical Society was coincident with the date when the newly founded color industry was emancipated from empirical methods and turned toward scien- tific synthesis. The first great success obtained through this agency was the creation of the alizarin industry, whose later development has surpassed all expectations. The recognition of the close connec- tion between constitution and properties of coloring matters found its practical application in the introduction of azo dyes, which not only brought into the industry an extraordinary variety of colors, but accustomed the dye chemist to develop almost quantitative methods of work. In the group of phthaleins were found not only some of the most striking coloring materials, but also some of the most permanent, thus refuting the theory, not proved, but then current, that artificial colors were ephemeral in the same proportion that they were brilliant. Equally permanent dyes were found among the eurhodines, safra- nines, oxazines, indulines, and thionines, the study of which is so intimately bound up in that of nitrogen chains and the joining of nuclei. The discovery by a mere chance of a fast alizarin blue, so 260 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. important from a technological point of view, likewise carried in its wake great consequences for scientific chemistry, for the investiga- tion of the composition of this dye led to a synthesis, capable of general application, of the derivatives of quinoline. In a like manner the explanation of the constitution of rosaniline was very productive in allowing the synthesis of numerous new compounds, among which are found some of the most beautiful and valuable dyeing materials. The appearance of substantive azo colors, and finally of those known as “sulphonated dyes,” has not occasioned the opening of any new avenues of scientific investigation. These two accomplishments, how- ever, are of the greatest importance in that they have provided new methods for dyeing and printing and have completely revolutionized these two ancient industries. Lastly, we may mention the new class of indanthrene colors in which are united clear tints with an hitherto unknown resistance to all destructive influences. Tt is the synthesis of indigo, however, that we must hail as the most brilliant of all the conquests in the field of coloring materials. We can still recall the day when the great event in chemical history was made public and when every hand was extended in congratulation for this masterpiece of scientific research. The struggle for a solu- tion to this great problem cost twenty years of assiduous labor, but, once solved, how well the new product of synthetic indigo has stood the test beside the natural product backed by several thousand years’ use. There is no hope that this industrial triumph in the coloring field will ever be surpassed. It is none the less certain, however, that this industry has not yet attained the limit of its development. Our reviews in the future will still record many achievements bearing witness to the uninterrupted development of this interesting and manifold branch of technology. We may consider the manufacture of synthetic medical prepara- tions as an offshoot of the color industry which sprang up in the period we are considering and which has already earned a position of its own. What brilliant results have been accomplished in this field, also. What a beautiful gradation of development from com- plex insufficiency to simple perfection can be witnessed in comparing kairine and thalline on one side and antipyrine, phenacetine, and as- pirine on the other. What a progress in the regulation of physio- logical functions is evidenced in chloral hydrate and veronal. What pains has not synthetic chemistry soothed by its activity in this field, what ills has not it assuaged. The industry of artificial medicines is only one of a vast circle of varied activities which we are in the habit of grouping together under the collective term of preparation industries. To properly appreci- TECHNOLOGICAL CHEMISTRY—WITT. 261 ate this industry with all its ramifications is impossible. Neverthe- less I can not help mentioning the appreciable growth of a branch of this industry which is almost as old as this society. This is the manufacture of chemical products and preparations for photography, whose expansion has been closely connected with the development of scientific photochemistry and with the introduction and populariza- tion of dry photographic plates with their proper processes of de- velopment. Not less interesting are the chemical and technical aspects of the perfumes newly created and developed during the last forty years. This field, which is completely developed along its principal lines at the present day, was still unexplored at the time when the German Chemical Society was founded. Its expansion is reflected more com- pletely in the pages of our transactions than anywhere else. Step by step nature has been imitated in its creations, and in this field perhaps more than anywhere else the synthetic chemist has taken paths which follow those of nature. Among synthetic industries we should count the technology of explosives, although here it is a matter less of constructing molecules than of storing up energy in a form easily liberated. In this indus- try great progress has been recorded, almost all of which depends on the utilization of the facts expressed by the law of Sprengel, ex- pounded about forty years ago, and on the employment more and more of safe explosives which can be detonated only by an initial ignition, in place of bodies themselves explosive. The possession of such explosives and the application to the phenomena of explosion of modern methods of observation have alone made possible the new orientation in ballistics, which is well known to all of us. If we consider all this technological progress that I have mentioned and much more which I must refrain from describing, we must agree that as far as applications are considered our science has reached a high state of development. But just as scientific research, in spite of the abundance of results, still presses forward, so will technology not stand still, but will continue to attack more and more difficult problems. When this society was founded there was already, it is true, a very well-developed series of chemical industries, but their activities were limited almost entirely to the extraction, purification, and transfor- mation of natural products. An industry operating synthetically on a large scale is a development solely of the last forty years. To- day we are striving for even more lofty ends. We have dared to lay a hardy hand even on the great processes of nature in seeking to influence them according to our needs. It is this that we behold in the great factories where many are striving to utilize the nitrogen of the air. Many methods have been proposed to attain this end; 262 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the combustion ef nitrogen to its oxides and the transformation of it into cyanogen or ammoniacal compounds have been used. All these methods are practicable and will all probably be productive of results. Which of these results will be the most important it is for the future to decide. In all of them, however, is this characteristic feature—they do not rob Nature of its amassed treasures, nor do they wish to imitate her creations; they aim merely to assist her in one of her greatest processes, the circulation of nitrogen. If we succeed in influencing this phenomenon, we will also in & measure control that other which is so intimately bound up with our fortune or misfor- tune, the course of life. We will force the earth to greater fertility, to an increasing habitability. In such a task Nature herself should be our ally. The savage force of the water which falls from above carries out the chemical work which we call upon it to perform, and a day is beginning to dawn ~ when it will be not only a pretty metaphor, but one of peculiar force and meaning, to speak of the fertile influence of the brooks which ripple down from the mountains into the valleys where stand the habitations of men. TWENTY YEARS’ PROGRESS IN EXPLOSIVES. [With 9 plates. ] By Oscar GuTTMANN, M. Inst. C. E., F. I. C., F. C. S. I. From the time of the invention of gunpowder, or approximately in the year 1250 (Roger Bacon at any rate knew of it in 1264), until the beginning of the nineteenth century no other explosive was introduced into practice, although picric acid and fulminate of mercury were known about the latter date. Experiments were carried out by Le Blond in 1756 in the French Government factory at Essonne to pro- duce gunpowder without sulphur, and a British patent for a powder containing “coal brasses” and without charcoal was taken out by De- laval in 1766,° but that was all. In 1788 Berthollet and Lavoisier tried the effect of adding potassium chlorate, and in 1861 Designolle made a powder from potassium picrate and saltpeter, but without much suc- cess. In 1846 Schoenbein invented gun cotton, and Sobrero in 1847 nitroglycerin, but the Austrian Government, which was the only one to try gun cotton in guns, stopped the experiments abruptly in 1867, their magazines at Hirtenberg having blown up, and, curiously enough, it is not until that date that Nobel began to work on dyna- mite. About the same time the British Government began to experi- ment with gun cotton at the point where the Austrians had left off, and introduced it as a blasting agent into the service, their example being then followed by other governments. In 1873 Sprengel made his well-known communication to the chemical society “on a new class of explosives,” which has since been named after him; and in 1878 it was again Nobel who invented blasting gelatine. About 1864 Abel and Doctor Kellner, of Woolwich Arsenal, made a granular gun- powder from gun cotton, and at the same time a sporting powder @ Reprinted, by permission, with abridgment by the author, from Journal of the Royal Society of Arts, London, Nos. 2927, 2928, 2929, Vol. LVII, December 25, 1908, January 1 and 8, 1909, and from volume ‘*“‘ The Manufacture of Explosives. Twenty Years’ Progress.” Whittaker & Co., London and New York, 1909. ’ Thomas Delaval, British patent No. 846, of 1766. 88292—sm 1908——18 268 264 ANNUAL REPORT SMITHSONIAN INSTITUTION. 1908. from nitrated wood, the Schultze powder, was introduced. Later on, in 1882, Reid made grains of soluble gun cotton, and hardened them by means of ether alcohol, calling the product “ EK. C. powder.” In the third lecture reference will be made to the important smokeless powder of Friedrich Volkmann made in 1870. Such was the state of the art in 1886, when simultaneously Eugene Turpin, of Paris, suggested the use of compressed or molten picric acid as a charge for shells, and Vieille carried out his famous experi- ments, resulting in the manufacture of the Poudre B (so named after General Boulanger). At the same time it was recognized that most explosions in coal mines were due to the ignition of fire-damp by the firing of shots, and that it was possible to make so-called “ safety explosives,” which would considerably reduce this danger. Hereafter investigations and inventions came in almost too rapid succession. Unfreezable dynamites, dinitroglycerin explosives, picric acid compounds and trinitrotoluene explosives, fulminates from aro- matic nitro-compounds, phlegmatized fulminate, detonating fuses, and many other varieties were invented. Nitrocellulose, than which there is hardly a more complex substance, was investigated by Cross and Bevan, Hiiusermann, Lunge, de Mosenthal, Vignon, Will, and others; the stability of nitro-compounds, the properties of nitroglyc- erin, and many other substances investigated by an army of workers. In fact, quite as important results have been obtained since 1886 as in the whole of the previous years. This is due, in the first instance, to the enormous amount of scientific research and experiment devoted by manufacturers to the study of such questions, partly because they were forced to do so by considerations of national defense, the advent of the rock drill, and by competition, and partly because those who lacked the training for such research could be persuaded by the results achieved to appreciate the work of others. Whilst until a generation ago the so-called “ powder maker ” was a craftsman, who carefully guarded little tours-de-main as valuable trade secrets, and even the inventors of high explosives had to advance in a most empirical way, it is recognized nowadays that only the best scientific knowledge can effect improvements or keep in line with modern developments of the industry. Whilst for warlike purposes the use of black powder, and even that of the later brown powder, has become a negligible quantity, blasting powder is still sold to such an extent that in the mines and quarries of this country alone nearly 7,000 tons of it, or more than half the total weight of all explosives, were used in 1907.4 This of course represents only part of the total quantity manufactured in this coun- try, since 3,597 tons of gunpowder of all kinds of British and Irish *Report of His Majesty’s inspectors of explosives for 1907. PROGRESS IN EXPLOSIVES—GUTTMANN. 265 production were exported,* and a good deal was used for railways, roads, etc. There has been practically no progress made in black powder within the last twenty years. Brown powder, which, as is known, contained slack burnt charcoal and a small percentage of sulphur, greatly improved the shooting of large guns, but has gradually given way to smokeless powder, even for the very largest guns. A little black powder is still used as a primer for large charges, but even for that purpose it will gradually be replaced by specially prepared smokeless powder. There are still some old sportsmen who prefer to use nothing but the old fine black sporting powder, and this is more especially the case in remote parts of Germany, Austria, and Italy, whilst in the United States of America profes- sional sportsmen, 1. e., those who shoot wild fow! for the market, use black powder because of its cheapness. There is a certain amount of competition going on in this quarter with smokeless powder, and manufacturers of black sporting powder are thereby obliged to make special efforts to produce material of the highest grade only. The enormous development of the German potash industry, and the peculiar requirements of potash and salt mining, have also re- vived some rough mixtures of black-powder-like explosives, of which very large quantities are now sold in Germany. In America, also, large quantities of black powder made with sodium nitrate are used. Labor there is so expensive that work is done with this cheap explosive which on this side of the Atlantic would be carried out with pick and shovel. Progress of a different kind has been effected by using ammonium nitrate as an ingredient in a powder mixture. This also was tried in France in the eighteenth century with but little result.2 Amide powder,’ however, made by the Koeln-Rottweil works, and con- sisting of 40 parts of potassium nitrate, 38 parts of ammonium nitrate, and 22 parts of charcoal, might, but for the advent of smoke- less powder, have become a serious rival to black powder. Mayer, of Felixdorf, in Austria, also worked in this direction. The Aus- trian Government makes Wetter-Dynammon as an explosive for fiery ynines, which, according to Ulzer,? consists of 93.83 per cent of ammonium nitrate, 1.98 per cent potassium nitrate, 3.77 per cent charcoal, and 0.42 per cent moisture, the charcoal grains being 1 to 6 » in size. @Private communication. > Bottée et Riffault, “ Traité de l'art de fabriquer la poudre 4 canon.” Paris, 1811. © Gaens, British patent No. 14412, of 1885. 7“ Mitteilungen des technologischen Gewerbemuseums,” Wein, 1900, p. 204, 266 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Further progress, although seemingly small, has been that made in powder for safety fuses. Formerly it was not uncommon to use the siftings from mining powder for safety fuses, but the present stringent requirements have compelled all manufacturers to make a special quality of fuse powder of constant composition, density, and uniformity of granulation, in spite of its almost dustlike char- acter. I shall lay before you later on some information concerning safety explosives for fiery mines, and, therefore, will only mention that in every Kuropean country the use of gunpowder is prohibited in such workings. Considerable surprise was therefore felt when several black-powder-like mixtures passed the official test for permitted ex- plosives in this country. Later, when these tests were made more rigorous, these explosives disappeared, but one of them, bobbinite, passed even the more stringent tests, and is still on the new list of permitted explosives. Complaints having been made as to the alleged danger of bobbinite in fiery mines, the home office appointed a departmental committee in 1906 to investigate the matter, which came to the conclusion that the use of bobbinite should not for the present be restricted.t The importance of this explosive may be gauged from the fact that over a million pounds of bobbinite were used in 1907 in this country. With regard to machinery used in the manufacture of black powder and similar mixtures there has, of course, been very little improve- ment. Mixing, granulating, and glazing are still carried out in the same way, and for the purpose which they have to accomplish the machines do all that can be desired. A good deal of ebonite was formerly used in connection with machinery for black powder, such as for plates in cake presses, for lining the hoppers of cutting ma- chines, etc. In cake presses there are alternate layers of powder containing sulphur, and of highly insulating ebonite, which remain together under pressure for some time. It is a rule in explosives works that at the approach of a thunderstorm the workers leave their houses, and it is frequently found convenient, meanwhile, to leave the charge under pressure. This would practically constitute an electric pile, and as a matter of fact several explosions have occurred when, after the thunderstorm, the workers opened the presses. In one in- stance, at least, the fact of a long spark having come out of the charge could be elicited from the attendant before his death. Following a suggestion made by the author twenty years ago, a number of factories have substituted plates of fiber for these ebonite plates with great success. “Report of the Departmental Committee on Bobbinite. London, 1907. PROGRESS IN EXPLOSIVES—GUTTMANN. 267 Chlorate mixtures have at all times fascinated inventors on account of the large amount of oxygen stored up in potassium chlorate, which ean be given off so readily. When Lavoisier and Berthollet tried to make a chlorate powder in a stamp mill in 1788, they made a great show of it, and even two ladies were present. Unfortunately after a certain amount of pounding the powder exploded and killed an official and the daughter of the government commissary, who assisted at the experiments. In this country we have for a long time refrained from licensing any explosive containing potassium chlorate, because such are so sily exploded by impact or friction. With the advent of electro- lytic methods for the manufacture of chlorine, potassium chlorate, and the like, chlorate explosives were brought within easy reach of the trade, and in fact the present price of electrolytic potassium chlorate will under certain conditions permit the economical manu- facture of suitable explosives. Hence greater efforts were made to render chlorate explosives more stable, so as to pass the home office test, and ultimately success was attained by the addition of some oil. Its function is evidently to so surround the potassium chlorate that, when mixed with carbonaceous matter, it becomes less sensitive. The addition of greasy matter to chlorate explosives is not at all a new idea. In 1867 already F. Hahn added spermaceti to a gun- powder containing chlorate. However, a practical explosive was ultimately obtained in cheddite, patented by Mr. Street,’ and so called because it was first made in Chedd, in Switzerland. The more usual variety is known abroad under the name of cheddite 60 bis, and its composition is 80 parts of potassium chlorate, 13 parts of mononitronaphthalene, 2 parts of dinitrotoluene and 5 parts of castor oil, whilst in this country the proportions of mononitronaphthalene and dinitrotoluene are reversed. It is interesting to observe how the same old mixtures are proposed over and over again with slight alterations only, in order to qualify for a patent. Potassium chlorate with some carbonaceous matter like charcoal, sugar, starch, glycerin, flour, or sometimes a vegetable or mineral oil and the like occurs again and again. One patent ¢ is of special historical interest, since it proposes the use of “ Maltha ” as an ingredient. The patentees came from California, an English- speaking country, and therefore it might be supposed that the name was not unfamiliar in England, but this appears not to be the case. T recollected, however, a passage in Roger Bacon’s “ Opus Majus ” as follows: “ Nam Malta, que est genus bituminis et est in magna copia in hoc mundo, proiecta super hominem armatum comburit “British patent No. 960, of 1867. bId., No. 9970, of 1897. © Quinby, Sharps and Greger, British patent No. 4781, of 1902. 268 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. eum ”—(Thus Malta, which is a kind of bitumen, and exists in large quantities in this world, when thrown on an armor-clad man, burns him to death). It seems, therefore, that the Mayflower took with her some Old World expressions and adapted them to the New World. The latest surprise is that in 1908 a chlorate explosive has been licensed as a safety explosive in this country under the name of “ colliery steelite;” it consists of 74 parts of potassium chlorate, 25 parts of oxidized resin, and 1 part of castor oil. The electrolytic chlorine industry has also made possible the manu- facture of pure perchlorates, and more especially of ammonium per- chlorate, which presents many advantages, although the objection has been raised that explosives containing this ingredient generate fumes of hydrochloric acid in the mine. Another class of explosives, which was from time to time used for ordinary blasting purposes, and of which very little has been heard in this country, are the Sprengel explosives. You have all heard of rackarock, which was employed in the blasting of the Hell Gate rocks near New York. Until the last decade it was hardly used anywhere except in America, but on building the first Chinese railways the Americans were able to introduce it.¢ A novel ingredient was introduced by Winand,? who mixes tetrani- tromethane with petroleum or other carbonaceous matter. A new departure was made in 1899, when Dr. Richard Escales, of Munich, invented the first aluminum explosive. There were only a few early attempts to utilize hght metals in explosives, until Escales showed that the addition of aluminum or magnesium very consider- ably increased the temperature of explosion and thereby the explosive force. His explosive was patented under the name of Wengheeffer,° and is now, I believe, manufactured, together with a similar explosive invented independently in 1900 by Ritter von Dahmen,? and since known under the name of “ ammonal.” Ever since aluminum has been taken as an ingredient in almost any kind of explosive. Theoretically it would be of very great value, but in practice the high price of aluminum powder and the possi- bility of oxidation under suitable conditions have somewhat militated against it. It is, however, used in Austria-Hungary for filling shells, for which purpose it seems well suited, not having given any trouble during ten years of storage, although I am told they sometimes fail to explode. It is also on the special list of the British home office as an explosive for fiery mines. “Karoly Gubaényi, ‘“‘The Rackarock Blasting Powder,” “ Magyar mérnok és épitész egylet kézlonye,” 1901, p. 165. > British patent No. 26261, of 1907. ¢ British patent No. 24877, of 1899. @Td., No. 16277, of 1900. PROGRESS IN EXPLOSIVES—GUTTMANN. 269 Other metals might have a similar or even a better effect than aluminum. Thus in 1900 already Désiré Korda, of Paris, and the author have considered the possibility of using ferro-silicon. In addition to the above-mentioned metals, the use of iron, silicon, silicon carbide, zine and its alloys, copper, and also the rare metals has been patented, In his patent of 1871 on the explosives bearing his name,’ Prof. Hermann Sprengel, F. R. S., said, seemingly without reference to the rest of the patent, “ I also employ picric acid,” but in his famous lecture delivered in 1873 before the Chemical Society he said dis- tinctly: “ Be it noticed here that picric acid alone contains a sufh- cient amount of available oxygen to render it, without the help of foreign oxidizers, a powerful explosive, when fired by a detonator. Its explosion is almost unaccompanied by smoke.” As a matter of fact, Sprengel did fire some shots with picric acid at Messrs. John Hall & Sons’ factory in Faversham in 1871, but was not encouraged by the service to pursue his experiments. Nothing further was heard of picric acid until 1886, when, as men- tioned before, Eugéne Turpin, of Paris, showed how to compress or melt it for use in shells. The French service used picric acid, mixed with collodion to give it greater density, under the name of melinite. Later on it was compressed, but ordinary detonators failed to explode it with safety, and the expedient devised by Alberts and the author to use a primer of dry gun cotton was too inconvenient. The picric acid has therefore to be melted, in which state it can be more readily exploded by detonators, and has a density of about 1.65. Picric acid melts at 122.5° C., and must therefore be either heated in an oil bath by high-pressure steam or in a special “ stove.” Melting it at such a high temperature is very Inconvenient and is not without danger, hence use was made of the well-known phenomenon that a mixture of two substances of high melting points has nearly always a lower melting point than that of either of its constituents. Girard? has given a long list of the melting points of explosive mixtures of this kind. Almost every country has adopted picric acid as a disruptive agent, under a different name, and differences in composition consist merely in the addition of an ingredient to reduce the melting point. Such additions are nitronaphthalene, camphor, dinitrotoluene, etc., and the names are melinite, lyddite, pertite, shimose powder, picrinit, ecrasit, ete. Besides having a high melting point, picric acid is inconvenient in other ways. Left in contact with metals or oxides it forms very dangerous picrates, hence the necessity of varnishing the interior of “British patent No. 2642, of 1871. bId., No. 6045, of 1905. 20 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. shells, giving special protection to the primers, and generally taking the utmost precaution to prevent access of foreign bodies while the acid is in the molten state. Picric acid has an intensely bitter taste (which is still more pronounced in the inky black smoke of burning picric acid), and therefore its manipulation is not very pleasant. It also imparts a fairly fast yellow coloration to the skin, which in some parts has procured the nickname of “ canary birds” to the workers in picric acid. (I have found that in one factory common salt was used for removing the yellow coloration from the skin, but why it should do so is not quite clear.) When used together with other ma- terials it must be remembered that, being an acid, it is liable to dis- place other acids; for instance, it sets free nitric acid from nitrates, and therefore while picric acid might be useful for increasing the power of certain explosives it would actually decompose them. Tn order to obviate these drawbacks Hauff had proposed the use of trinitroresorcine * and the Chemische Fabrik Griesheim that of trini- trobenzine” and trinitrobenzoic acid.° These substances were not favorably received, but trinitrotoluene has within the last few years come very much to the fore, and also possesses a great many good qualities. Its melting point varies between 72° and 82° C. It may be handled with almost perfect safety if pure, does not give off nox- ious fumes on melting, is quite stable, does not combine with metals, and generally has no acid properties. Like picric acid it is only slightly soluble in cold water. It is slightly less powerful than picric acid, which is rather an advantage, since the latter frequently pul- verises a shell, instead of bursting it into a number of fragments sufficiently large to have destructive effect. Trinitrotoluene is very easily detonated. I have been able to explode it in the form of pow- der, with a No. 3 detonator only (0.540 gram of fulminate compo- sition). Trinitrotoluene has been introduced into the French service under the name of tolite. The Spanish Government call it trilit. The carbonite works of Schlebusch are introducing it into other services under the name of trotyl, and Messrs. A. and W. Allendorf, of Schcenebeck, under the name of trinol, whilst other factories retain the name of trinitrotoluol. The manufacture of trinitrotoluene is carried out in stages, like that of most aromatic nitro compounds. Great care has to be taken to purify the toluene, since that usually found in commerce contains benzine and other compounds. Nitration is effected in enameled iron vessels, and purification of the higher nitrates, which cake to- gether during nitration, has to be performed with some care. Wash- 4 British patent No. 9798, of 1894. +’ German patent No. 79477, of 18938. CTd., No. 79814, of 1893. PROGRESS IN EXPLOSIVES—GUTTMANN. par ing is usually completed in centrifugals. In order to obtain the best quality, melting between 81° and 82° C., trinitrotoluene made from purified toluene, and having a melting point of 77° to 79° C., is recrystallized from alcohol in vacuo. The machinery for effecting this is not very complicated, but always specially designed. In this country alcohol is somewhat dear and inconvenient to use, in spite of facilities afforded for obtaining it duty free, and petroleum ben- zine is therefore employed for recrystallizing the trinitrotoluene; it is said, however, that a slightly darker color is imparted by this method to the product, to which objection is taken in some countries. The density of trinitrotoluene when loose being 1.50 and when molten 1.600, means have been devised to increase it. Rudeloff « ob- tains a density of 1.85 to 1.90 by making a plastic substance from trinitrotoluene and potassium chlorate with a gelatine made from dinitrotoluene and soluble nitrocellulose. Bichel makes a plastic com- pound with collodion cotton, liquid dinitrotoluene, and larch turpen- tine, calling it plastrotyl.’ Messrs. Allendorff mix the trinitrotoluene, together with some lead nitrate or chlorate, with a gelatine made from dinitrotoluene and nitrocellulose, and call it triplastit. This is an improvement on the way the French Government made melinite with collodion, or Wolff & Co. filled gun-cotton slabs into shells with paraffin wax. Bichel also melts the trinitrotoluene, and after first exhausting all occluded air, compresses it by introducing compressed air above it. Bichel has in this way obtained densities up to 1.69. Rudeloff presses it in hydraulic presses under a pressure of 2,000 to 3,000 atmospheres, whereby it obtains a density of 1.7, and can be cut and worked like gun cotton. For the purpose of facilitating detona- tion, some loose trinitrotoluene is used as a primer. Trinitrotoluene is also used in detonators, of which further mention will be made later on. Another new explosive for filling shells is used in Spain under the name of tetralit.? It is said to be made from tetranitromethylamine, and to be more sensitive than trinitrotoluene, but very little else is known. During the last three or four years newspapers contained accounts of trials with a new explosive, at first called vigorite and now bava- rite, the invention of Professor Schulz and Mr. Gehre, which is said to cost only one-third as much as other explosives, and to be ever so much more powerful. On examining the patent? one finds that this a“ Zeitschrift fiir das gesamte Schiess- und Sprengstoffwesen,”’ 1907, p. 7. > British patent No. 16882, of 1906. ¢Td., No. 19215, of 1906. @“ Zeitschrift fiir das gesamte Schiess- und Sprengstoffwesen,” 1908, p. 308. € British patent No. 5687, of 1905. 242 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. is nitrated solvent naphtha. It must be embarrassing to the inventors to see such improbable accounts of manufacturing costs and exagger- ated effects produced by the explosive published in newspapers. Il. I have mentioned in my previous lecture that Sobrero invented nitroglycerin in 1847. It is known that, although he recognized the value of this invention for civil and military blasting purposes, prac- tically no use was made of it until 1867, when Alfred Nobel invented dynamite, and was not deterred by accidents and prejudice from introducing it into the service of mankind. You know that before this time Mowbray, in Massachusetts, manufactured nitroglycerin and carried it into the mines in the frozen state. Nobel devised processes for the manufacture of nitroglycerin on a large scale, and the machinery for it was constructed to his ideas by his lifelong adjutant, Mr. Alarik Liedbeck, of.Stockhelm. Since there is a full description of all the apparatus in use in my book on The Manufacture of Explosives, which appeared in 1895, I can con- fine myself to dealing with progress made since that date. You will find described in this book two kinds of apparatus for nitrating glycerin, such that have a helical revolving stirrer for mixing pur- poses and such that are agitated by compressed air. Occasionally both mechanical and compressed air stirring are used. One has learned in time to control the operation of nitration more efficiently, and this inspired confidence to increase the size of the apparatus. I believe the largest apparatus made in lead nitrates 680 kilograms of glycerin at one operation, while in America and South Africa steel apparatus with mechanical stirring gear are mostly used, some nitrating 1,000 kilograms at a time. In one United States works they have gone so far as to have four such steel nitrators, each for a charge of 1,000 pounds of glycerin, in one room and driven from one main shaft, but present practice is to have two such nitrators in one building. In this country one would not allow more than one nitrating apparatus to be used at a time. Of course each nitrator is provided with a series of lead or steel coils through which cold water circulates, and it has now become frequent to install a refrigerating plant and to circulate water of only 10° C. and less through the coils. With regard to the composition of the nitrating mixture, it has been customary in well-conducted factories during the last twenty years or so to nitrate 110 kilograms of glycerin in a mixture of 300 kilograms of nitric acid of about 93 to 94 per cent monohydrate and 500 kilograms of sulphuric acid of 96 per cent monohydrate (and not, as Sir Frederic Nathan and Mr. Rintoul stated, 100 parts of glycerin PROGRESS IN EXPLOSIVES—GUTTMANN. 23 and nitric acid of 91 per cent only).* This corresponds to about 255 parts of nitric acid monohydrate and 436.4 parts of sulphuric acid monohydrate, or a total of 691.4 parts of acid monohydrate with 35.8 parts of H,O (4.9 per cent) to each 100 parts of glycerin. It is now customary to add sulphuric acid cntaining 20 per cent of anhydride (oleum) to the original mixture, but it is still found impracticable to add it to the waste acid. It will be seen from the paper of Sir Frederic Nathan and Mr. Rintoul on “ Nitroglycerin and its manufacture ” that the use of anhydride has reduced the quantity of sulphuric acid required. Five years ago already I found in the Pozsony factory of Nobel’s the use of mixed acid consisting of 37.2 per cent HNO,, 60 per cent H,SO,, and 2.8 per cent H,O, and made with anhydride. Although no artificial refrigeration was used, the yield of nitroglycerin amounted to 220 for 100 glycerin, and a ratio 6.318 of acid to 1 of glycerin. Factories using Nathan, Thomson, and Rintoul’s process now employ a mixture of 41 per cent HNO,, 57.5 per cent H,SO,, and 1.5 per cent H,O, corresponding to 250 pounds HNO,, 350 pounds H,SO,, and 9 pounds H,O for each 100 pounds of glycerin, which gives a ratio of 6.09 of acid to 1 of glycerin, as against 6.91 to 1 formerly required. It is thus seen that this process requires about the same quantity of nitric acid per 100 glycerin as the old process, but about 86 pounds, or roughly 20 per cent, less sulphuric acid. It will therefore simply depend upon the price of the sulphuric anhydride whether it is advantageous to use it. With the present prices of £3 per ton of 96 per cent sulphuric acid and £3 15s. 0d. per ton of sulphuric monohydrate, containing 20 per cent of anhydride, the difference between the cost of materials with the former yield of 220 and the present one of 229 nitroglycerin is, per ton, £3 Os. 2d, or approximately 5.6 per cent. This apparent saving is quite counterbalanced by the fact that in the new process 1.9 tons less of waste acid are obtained. In making this comparison it must, however, be remembered that with the new process the same apparatus will hold 18 per cent larger charges. After nitration the mixture is allowed to stand, when the nitro- gylcerin separates from the waste acid and floats on the top of it. The separation is sometimes considerably delayed by the formation of a silicious colloid, which agglomerates with particles of cell sub- stance and other impurities, forming fern-like growths. The Dyna- mit Actiengesellschaft in Hamburg? found a very efficient means of promoting separation in the addition of high-boiling paraffins in « Journal of the Society of Chemical Industry, March 16, 1908. Compare also Guttmann, Manufacture of Explosives, Vol. II, p. 93. > British patent No. 13562, of 1904. 274 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. quantities of 0.5 to 2 per cent of the weight of glycerin, while Dr. L. F. Reese, of Wilmington,* adds as little sodium fluoride as 0.002 per cent (1 in 50,000) of the glycerin employed to the nitrating mixture with excellent results. Both methods are now used in very large factories. For more than thirty years some factories had been in the habit of employing one vessel only for both nitrating and separating, and withdrew the nitroglycerin from three earthenware cocks, placed at short intervals at the separating line. This enabled them to gain considerably in levels and to carry out the manufacture right up to the final washing on practically the same level. The waste acid was always sent to after-separation houses, which were frequently called by the German name of “ Nachscheidung.” Since the waste acid sometimes had to be kept in these after-separation houses for a week, in order to get rid of all the drops of nitroglycerin which separated out, decomposition occasionally set in. A plan was thereupon introduced in France and elsewhere which consisted in gradually diluting the waste acid by the addition of from 2 to 3 per cent of water, thereby stopping the further formation and separa- tion of nitroglycerin. At the government factory at Waltham Abbey these methods have been improved upon. A so-called “nitrator separator” is used, in which the nitroglycerin has time to separate from the acids, and waste acid is then added from below, thereby bringing the level of the nitroglycerin to a point where it will run out through a gutter into the preliminary washing tank. In this way the use of cocks is avoided. When all the nitroglycerin has been displaced about 2 per cent of water is introduced gradually. The result of this combination of a number of useful processes, namely, the employment of anhydrous sulphuric acid to produce a mixed acid containing little water, the use of refrigerated water to cool the acids, the displacement of the nitroglycerin by means of waste acid, which obviated the remixing of acid and nitroglycerin on emptying the nitrator, and the addition of water to stop the separation of further quantities of nitroglycerin, was that they together contributed to yield much better results. As a matter of fact in well-conducted works the yield of nitroglycerin with the proportions of 6.91 to 1 mentioned above was between 217 and 220; at Waltham Abbey it was possible to obtain by the “ displacement process” a yield of 229 parts nitroglycerin for 100 parts glycerin, instead of the former 220 parts. According to Mr. de Mosenthal the Nobel works obtained similar good results. This yield has to the author’s knowledge been only once exceeded in a Belgian factory, when a charge of nitroglycerin had to be drowned on a cold winter’s “British patent No. 20310, of 1905. Smithsonian Report, 1908.—Guttmann. . PLATE 1. NITRATOR SEPARATOR (NATHAN, THOMSON, AND RINTOUL’S PATENT). Smithsonian Report, 1908.—Guttmann. PLATE 2, CALCINED KIESELGUHR. PROGRESS IN EXPLOSIVES—-GUTTMANN. OT day. The contents of the tank froze and required two days to thaw; a yield of 240 parts nitroglycerin was, however, the surprising result. With regard to the selection of apparatus, round lead or steel tanks, as explained above, are generally used, but the author has also seen square-cornered ones. The Americans are much in favor of mechanical stirring, whilst in Europe air stirring is preferred. Hav- ing worked with both, I can not see much difference as regards re- sults, but since I do not like to have any moving parts in connection with the manufacture of nitroglycerin I think air stirring is pref- erable, on the whole. here has been no special improvement in the manufacture of dynamite since Nobel in 1875 invented blasting gelatin. In this connection it will be interesting to have a true picture of kieselouhr as used for dynamite. Mr. Henry de Mosenthal, whose skill in preparing specimens for the microscope we had often occa- sion to admire, has prepared for me various slides of kieselguhr. For blasting gelatin, as you know, a so-called “ collodion cotton ” or soluble nitrocellulose is employed. Many people think that if 7 per cent of nitrocellulose is insufficient to make a stiff and suitable blasting gelatin, the addition of another 1 or 2 per cent would do it, and certainly at first the resulting gelatin is so stiff and hard as to require special effort in the cartridge machines. After a few months of storage, however, or after passing over the equator into Australia, nitroglycerin is found to exude. A good nitrocellulose will give a perfectly stiff blasting gelatin, with between 6 and 7 per cent of nitrocotton, and if a 24 per cent solution is made in a porcelain basin, the resulting gelatine should be easily detachable after cooling, show- ing no signs of exudation. There has been within recent years a revival of old ideas, but with better success, for the purpose of obviating one of the chief objections to dynamite, namely, that of freezing. It was in 1866, in Sweden, that A. E. Rudberg patented the addition of nitrobenzine to nitro- glycerin for the purpose of making it unfreezable.* The Société des Poudres et Dynamites, of Arendonck, found later® that the addi- tion of dinitrotoluene dissolved in nitroglycerin was very useful in lowering the freezing point. A new departure was really made when Dr. Anton Mikolajezak in 1904 patented the addition of dinitro- glycerin to trinitroglycerin explosives, and at the same time indicated a practical method of manufacturing it. It is now made on a large scale in a factory at Castrop, in Germany. In order to understand the question better it is necessary to point to a most interesting work * Swedish patent, April 30, 1866. ® British patent, No. 14827, of 1908. ¢ld., No. 8041, of 1904. 276 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. by Sigurd Nauckhoff,* showing why nitroglycerin can sometimes be subjected to intense cooling without freezing (supercooling), and to a paper by Dr. H. Kast,’ showing that there are two kinds of nitro- glycerin (one being an allotropic modification), with two different melting points, one nitroglycerin solidifying at about 13.2° and the other at about 2.1°, the melting points being 13.5° and 2.5°, re- spectively. Professor Will found that dinitroglycerin is not a sure guaranty against solidification, and that under certain conditions explosives prepared with it may become solid at a higher temperature than trinitroglycerin explosives. Of all these additions none has so far been definitely adopted for the manufacture of unfreezable dynamites, but, I believe that lately dinitrodichlorhydrine has been used with considerable success by the German works of the Nobel companies. We now come to gun cotton. The really important step in the manufacture of gun cotton was taken when the British Government adopted a process of pulping and purifying the gun cotton, first patented by John Tonkin, jr., of Poole, near Copperhouse, in Corn- wall,’ and again in combination with the compression of the pulped gun cotton, three years later, by Sir Frederick Abel.4 The next step was made when the principle of the detonation of nitrocompounds by means of a small fulminate of mercury charge, invented by Alfred Nobel,’ was extended by Mr. Brown, Sir Frederick Abel’s assistant, to gun cotton.’ Baron von Lenck, the Austrian general, who worked most assidu- ously as the pioneer of Schénbein’s invention, used gun cotton in hanks; the British Government introduced the use of cotton waste from spinning and other operations where threads are made. The reason for this change is not quite apparent, unless it was felt that since the cotton had to be pulped in any case the cheaper waste might do just as well as the long threads. This use of cotton waste has con- tinued ever since. It is very curious that in the purchase and use of nitric and sul- phuric acid for the nitration of gun cotton most stringent conditions are laid down with regard to freedom from mineral matter, chlorine, sulphates, arsenic, etc. Yet, as far as I could ascertain, no special precautions seem to be taken in the case of cotton to guard against a“ Zeitschrift fiir angewandte Chemie,” 1905, p. 11. bo“ Zeitschrift f. d. ges. Schiess u. Sprengstoffwesen,”’ 1906, p. 225. ¢ British patent, No. 320, of 1862. dTd., No. 1102, of 1865. € Td.,- No. 1345, of 1867. fId., No. 3115, of 1868. PROGRESS IN EXPLOSIVES—GUTTMANN. Patt impurities. Asa matter of fact, uncarded cotton waste as used for gun cotton generally contains a quantity of strings, wicks, colored threads, india rubber, or elastic cords, and similar leavings, showing the origin of the waste, and no amount of hand picking can free the cotton absolutely from such impurities. I have further found in cotton supplied by manufacturers of the best repute a large amount of chlorine, sulphate of lime, and sulphides, besides organic and mineral dust, which gives the cotton quite a gray appearance. Is it not also strange that it never occurred to anybody—at least as far as I know—to ascertain whether the impurities in the cotton, brought about by forcible treatment with bleaching agents and acids, are responsible for a great deal of the instability of certain finished gun cotton and smokeless powders? I am convinced that this is the case. Nobody seems to have given it a thought that such a complex com- pound as cellulose in the shape of cotton must vary to an enormous extent, both in its physical and its chemical structure, and thereby also the nitrocellulose made from it. Let us examine the possible changes. In the first instance we have the cotton itself, which may be in any stage of ripeness. The investigations of Leo Vignon® on the formation of oxycellu- loses and hydrocelluloses, and the behavior of their nitro compounds, show plainly how cotton and cotton waste may, by the nature of the treatment they undergo, be partly transformed into oxycellulose, which gives an unstable nitro compound, and into hydrocellulose, which has a different rate of nitration than ordinary cellulose. I have repeatedly stated on previous occasions that in my opinion the process of nitration with a mixture of sulphuric and nitric acids results, in the first instance, in an attack on the cotton by the sul- phuric acid similar to that in the manufacture of vegetable parch- ment, and that the sulphuric acid is gradually displaced by the nitric acid penetrating the fiber. It seems a fact that the more oxycellulose is formed in the cotton before nitration, the more unstable are the compounds formed in the nitrocellulose. Other impurities in the cotton are all the more likely to endanger the stability of nitrocellulose, as their nature is always unknown, and varies from sweepings to india-rubber elastics, while almost all are sure to produce unstable compounds. How far the nature and origin of the acids may have an influence upon the ultimate product has still to be investigated. I do not think that differences in apparatus used for the manufac- ture of nitro-cellulose have much to do with its stability. I have strong reasons for not recommending iron vessels for stabilization in * Comptes rendus, June 6, 1898, September 10 and 17, 1900. 278 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the first instance. I believe that if one must use nitrocellulose, and if, as seems to be the case, cotton is the best material for making it, one ought to use the natural cotton only, and not common yarn, and less still waste, which have both undergone so much forcible mechanical and chemical treatment as to completely alter the character of the cellulose and introduce elements of uncertainty and danger. These should be avoided by the use of ripe raw cotton, which, of course, would have to undergo suitable treatment to eliminate fat, husks, and other impurities, but would not necessitate the whole bleaching operation with its attending defects. Formerly the mixture for gun cotton consisted of 1 part of 1.500 nitric acid and 3 parts of 1.840 sulphuric acid, and each charge was revivified by taking away one-quarter of the waste acid and adding a mixture rich in nitric acid, so as to obtain about the original com- position. The following table shows the result of revivifying the waste acid ten times in a series of operations made in 1886 by Doctor Abelli and the author: Composition of nitra- Composition of waste ; ting esa peeeesce meareer : : eae acid. Number. ature of | Yield. N. TA , | nitration. : H2SO4.| HNO3.| He2O. H2SO4.| HNO3.| HeO. Degrees. | Per ct. | Per ct. | Per ct. | hee ee ee 72.82 | 24.37 2.81 20 | 146.25 | 13.32 3.60 | 75.15 | 19.00 5.85 Pn Be oe ECA IES 71.82 | 23.00 5.18 10 | 167.50 | 13.34 2.10 | 76.00} 18.40 5.60 SP meals ne ie 72.45 | 22.52 5.03 14 | 169.00 | 13.39 7.20 | 73.40} 19.10 7.73 Ce te Sees e a | 70.21 | 23.05 6.74 10 | 165.75 13. 49 2.93 | 71.40} 20.22 8.38 ego feast se ee a 68.77 | 25.97 7.26 12 | 175.00 | 13.38 2.88 | 71.06 |} 20.51 8. 43 i paoseeso nese aae 69.47 | 23.40 7.32 10 | 166.25 | 13.08 2.26) T1.72 19. 43 8.85 Uspecesacitic cease TAOS UU Moraes! 7.66 10 | 165.00 | 13.40 4.00 | 71.71 18. 82 9. 47 eS AE eee | 70.00} 21.85 8.85 152.50 | 13.30 4.80 | 70.70] 19.35 9.95 (eecna te soasse see 69.18 | 22.5: 8.24 167.50 | 13.22 1.60} 71.00} 19.13 9.87 NE eepospeeeesesee 69.40.| 22.00 8.60 9°] 152550 | 13521! 3.46 | 70.00} 19.00 11.00 The original mixture consisted of 1 part of nitric acid to 3 parts of sulphuric acid, both of over 97 per cent monohydrate. Three parts of waste acid were revivified with 1 part of fresh acids. It will be seen that the percentage of nitrogen contained in the nitrocellulose reaches a maximum when the percentage of water in the acid mixture is about 9 per cent, and not, as might be supposed, in the stronger acid. The majority of factories prepare the nitrating mixture by giving special consideration to the percentage of water in the first instance, because by varying this nitrocellulose of widely different proper- ties can be obtained. I have often said that by varying the concen- tration of the acids, their temperature, and the time of nitration one has three factors, each of which can to a certain extent influence every property of the nitrocellulose obtained. It is the custom in a major- PROGRESS IN EXPLOSIVES—GUTTMANN. 279 — ity of factories to produce soluble nitrocellulose by taking equal parts of nitric acid of 75 per cent monohydrate and sulphuric acid of 96 per cent monohydrate and nitrating the cotton at a temperature of 40° C. This nitrating acid therefore contains 14.5 per cent of water. Yet by merely altering the proportions of acid it is quite possible to make very good soluble nitrocellulose in the cold, and some modern factories make it in this way. It seems to be very difficult, if not im- possible, to obtain good and stable completely insoluble nitrocellulose from wood pulp. It is now recognized on all sides that there are no definite stages of nitration in nitrocellulose, but that the change in composition goes on without a break, if the conditions are suitable. The manufacturer of gun cotton and nitrocellulose is face to face with great difficulties. Almost everything he does tends to act detrimentally. From the nitration his nitrocellulose contains a number of lower nitro com- pounds, nitrated oxycellulose and hydrocellulose, nitrosaccharoses, ete., which he has to get rid of. The usual way to do this is to boil the nitro cotton for a long time. It is not quite clear why one should keep on boiling the long and closed-up fibers of unpulped gun cotton for, say, fifty hours, as is done in some factories. One would imagine that if after a preliminary washing or boiling the gun cotton were pulped and then boiled this could be done much quicker. As a matter of fact, I have found that by heating the gun cotton whilst pulping the in- crease in stability is very much accelerated, and several factories use the method with advantage. In France they boil for one hundred hours, and I have quite lately seen nitrocellulose that was boiled for two hundred hours without, however, being much the better for it. It must, however, be mentioned that the Waltham Abbey gun cotton as at present made is a very stable and good gun cotton, as judged both by the iodide test and by the destructive test, of which more will be said later on. This is due, in the first instance, to an investigation carried out by Doctor Robertson. He showed that the former method of giving short boilings of two hours and following them up with long boilings of eight and twelve hours was erroneous, and that two long boilings of twelve hours each would liberate acid from the nitro- , cellulose, giving an acid water which hydrolizes all the impurities without attacking the gun cotton itself, and that subsequent short washings are useful in eliminating the products of hydrolysis. Having had frequent occasion to put Doctor Robertson’s principles to a practical test, I consider it to be one of the most useful pieces of work accomplished since the invention of gun cotton. Messrs. Selwig and Lange, of Braunschweig, have invented the so- called “ nitrating centrifugal machine,” wherein the cotton is dipped and allowed to stand for the requisite time, and, the nitration being $8292—sm 1908——19 280 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. ° complete, the centrifugal is set in motion and the acid wrung out. In other words, the removal of the nitrocotton and nitrating acids from the pots into the centrifugal machines is avoided. I am perhaps an heretic, but I have never been able to see the advantage of these nitrat- ing centrifugal machines. They cost a great deal of money; they are hable to get out of order; one can only nitrate about 8 kilograms of cotton in each, and with a nitrating period of, say, half an hour, one can at the best make 10 charges a day in each; further, if the nitrating time is an hour, the number of nitrations is about 7 only. This means that for a fairly large production one requires a large number of centrifugals, and it is easy to calculate what this would mean in an artificial silk factory producing, say, 3 tons of nitrocellulose per day. The quantity of acid used for nitration must be greater, because the space between the basket containing the cotton and the jacket of the machine has to be filled up with acid, and similarly there are a good many other disadvantages. There is no difficulty in arranging pots or basins in such a way that the fumes arising from them are led away by means of an earthenware fan into an absorbing tower, just as is done in nitrating centrifugals and discharging these nitrating vessels into a wringing machine without its being necessary to expose the workmen to fumes or spilt acid. Such factories have been working very many years and give every satisfaction. Since there is an excess of waste acid produced in revivification, this waste acid is sometimes denitrated in the same way as the acid from nitroglycerin manufacture, but may more advantageously be used in manufacturing fresh nitric acid, because in this case the nitric acid contained in the waste acid is recovered as pure monohydrate. Revivification is nowadays very frequently carried out with sul- phuric acid containing 20 per cent of sulphuric anhydride (oleum). When the gun cotton is pulped and finished it is frequently packed and pressed into boxes. Gun cotton can become moldy on the out- side through fungi and, according to v. Forster, have its structure destroyed; % and y. Forster found this was promoted by paper in the cases, whilst Malenkowicz’ showed this to be due to moisture acting on the wood of the boxes. It is very important to select proper pack- ing material on account of the possibility of detrimentally influencing the stability. A new process for the nitration of cotton is due to Messrs. James Milne Thomson and William Thomson, of Waltham Abbey,’ and it has already been introduced in some factories. An earthenware fun- nel-shaped vessel can be connected at its stem by means of cocks, 4@Max y. Forster, “ Versuche mit comprimirter Schiessbaumwolle,” Berlin, SSS. seas > * Mittheilungen tiber Gegenstiinde des Artilleriewesens,” 1907, p. 599. ¢ British patent No. 8278, of 19038. Smithsonian Report, 1908.—Guttmann. PLATE 3. NITRATING CENTRIFUGALS. “(SSS0OUd LNAWZOVIdSIG LNASLVd SitNOSNWOH]) NOLLOD JO NOILVYLIN ‘p ALV1d ‘uuRW}No— 9061 ‘Hoday ueiuosyyiws PROGRESS IN EXPLOSIVES—GUTTMANN. 281 either with a pipe supplying fresh acid or with a discharge pipe. An earthenware grating closes the opening of the stem, the new acid is introduced, the cotton dipped in it in the usual way, and then segments made of perforated earthenware plates are laid on top so as to immerse the cotton completely. A small vessel with four outlets is now laid on top, and a Segner wheel distributes water evenly into it, and this is so regulated as to flow out quite slowly and lay itself on the top of the acid without disturbing the latter. This layer of water retains all fumes that may arise from the acid, so that the air in the room is quite good. When nitration is finished water is again allowed to run in, but at the same time connection is made with the outlet pipe, and, the flow of the water being carefully regulated, it gradually displaces the acid. Finally the nitrocotton can be given a preliminary washing. This process gives very good results, and is very convenient for making gun cotton as required for the British Government, which contains a fairly large percentage of soluble nitrocellulose. As yet there are hardly sufficient data available to decide whether the dis- placement process will give equally good results for gun cotton with a small percentage of soluble, or, what is far more important for smokeless powder, whether it will enable a soluble nitrocellulose with definite propertiés to be made, which, as is known, is always % some- what difficult matter. It was somewhat of a surprise when Arthur Hough, of New York,¢ announced that he could nitrate starch so as to contain at least 16 per cent of nitrogen. You will remember that Hoitsema ” has already studied the possibility of producing higher cellulose nitrates than hexanitrocellulose by keeping up the strength of the acid with phos- phoric anhydride. Hough seems to have found the practical solu- tion. This nitro-starch has been utilized in the manufacture of smokeless powders, and I understand that it is used to a certain ex- tent in the United States Army. TE. In the year 1580 Michel Eyquem de Montaigne, in his “ Essais,” wrote with reference to gunpowder: “ Except to astonish the ears, to which by now everybody is accustomed, I believe this is a weapon of very little effect, and I hope that we shall one day give up its use.”° Would anybody have dared to repeat such a thought thirty years ago? Yet it has come true. 4 British patent No. 12627, of 1904. o“ Zeitschrift fiir angewandte Chemie,’ 1898, p. 273. e“Sauf ’étonnement des aureilles, 4 quoy désormais chascun est apprivoisé, je crois que c’est une arme de fort peu d’effect et espére que nous en quittons un jour l’usage.” 282 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. About the year 1410 we find that quaint treatise on gunpowder called “ Feuerwerksbuch,” said to have been written by a master gunner, Abraham von Memmingen. It contains the famous history of how Berthold Schwarz tried to make a gold paint and invented gunpowder and guns instead. This book was lent to other master gunners, who severally copied and enlarged it, until in 1534 it was printed in Frankfort on the Main under the title, ‘“ Biichsenmey- sterei.” In this printed edition we find a prescription, “how to shoot out of a gun as far with water as with gunpowder.” Take 6 parts of nitric acid, 2 parts of sulphuric acid, 3 parts of liquid ammonia, and 2 parts of “ oleum benedictum” (crude tar oil), and charge the gun to a tenth part of its bore. It further advises quaintly, “ Light it quickly, so as to get away in time. See that the gun is very strong. With an ordinary gun you can shoot 3,000 paces with this water, but it is splendid.” This is the first evidence of a nitrated organic substance having been used as a propellant. I have already alluded to the history of the invention of gun cotton, but one reference remains to be given, showing how early the use of gun cotton in rifles was thought of. It is known that Schénbein reported on his gun cotton on March 11, 1846, and on May 27, 1846, he made experiments with rifles. Professor Otto, of Brunswick, had, independently of Schonbein, also made gun cotton, and published his results on October 5, 1846. He also tried gun cotton in a rifle, and Doctor Hartig published a pamphlet in 1847 at Brunswick, under the title “ Untersuchungen tiber den Bestand und die Wirkungen der explosiven Baumwolle” (Experiments on the Condition and Effects of Explosive Cotton), and therein he makes a statement, which has since attained great importance. He says that the effect which acetic ether has on “ the shooting fiber ” is very remarkable. He has found that if he makes a stiff, clear jelly with this ether from the shooting fiber, it does not alter its chemical state, and if put in a thin layer on a plate of glass, a snow-white residue is left after the ether has evaporated. If this residue is put into dilute alcohol and then dried it will have in every respect the same properties as the shooting fiber. He mentions already that probably on account of the altered state of aggregation there is a considerable diminution of the explosive force. Nothing was heard of a real powder made of nitrocellulose for a very long time. It is true that in 1847 the Commission de Pyroxyle, which was appointed in France, “ experimented with it in every form, as wadding, spun, twisted, woven, reduced to powder by the action of paper makers’ cylinders, felted together by means of dextrine, finally granulated like cannon powder,” * but it was too violent for @“ Note sur la pyroxyline ou coton-poudre,’ par M. Susane, Mémoires de VAcadémie Impériale de Metz, 1855. PROGRESS IN EXPLOSIVES—GUTTMANN. 283 use in guns and rifles. Baron von Lenck, in Austria, made gun charges from fibrous gun cotton, and we know that they were not a success. In 1865 Capt. Eduard Schultze, of Berlin, published a pamphlet on his “ new chemical gunpowder,” in which he gave the first indication of his powder, but more words than details. At the same time, however, a number of German journals published some particulars of its manufacture. Very soon after Schultze used finely pulped nitrocellulose, and made powder grains by agglomeration with water in drums. It is also remarkable that in 1865 Abel ¢ patented the production of grains of gun cotton by placing a mix- ture of gun cotton with water and a little gum arabic in a pan, and giving it a shaking motion, whereby the gun cotton was formed into grains. He also proposed to mix soluble and insoluble gun cotton, and to make the soluble gun cotton serve as a binding material by treatment with wood spirit, alcohol, ether, or mixtures of these liquids. It is further interesting that Doctor Kellner, of Woolwich, is mentioned in a German book which appeared in 1866” to have been the first to succeed in making a granular smokeless powder. Neither Abel nor Kellner seem to have continued at the gelatiniza- tion of nitrocellulose. The author well remembers, however, a firm in: Marchege, near Vienna, which existed under the name of Volkmann’s k.k. priv. Col- lodinfabriks Gesellschaft H. Pernice & Co. They originally bought the patent for the Schultze powder, and made it under the name of nitroxylin. From 1872 to 1875 they made a powder called collodin, the invention of Friedrich Volkmann, which was patented under date November 8, 1870, and May 31, 1871. After three years of existence the Austrian Government ordered the works to be closed, because they claimed that this explosive was infringing their gunpowder monoply. Volkmann cut up alder wood into small grains of the size of black powder, boiled, and washed, then bleached them, and after final boiling nitrated them in a mixture of nitric and sulphuric acid. Thus far the treatment was that usually given to cotton waste. The fin- ished grains were soaked in a solution of potassium nitrate, or of potassium nitrate and barium nitrate, and, after drying, treated with a mixture of 5 volumes of ether to 1 volume of alcohol. The solvent was allowed to penetrate the grains completely, and the more the substance was dissolved the more the volume decreased. On taking the powder out of the solvent it had the appearance of a mush, which, after twelve hours’ drying at 30° C., was converted into a dough, a pasty, pliable substance, from which any shape could be obtained by molding and pressing. Volkmann seems to have known everything about a smokeless powder. 7British patent No. 1102, of 1865. >“ Buch der Erfindungen,” Leipsic, 1866, chapter on gunpowder and arms, 284 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. In 1882 Mr. Walter F. Reid patented * the agglomeration of nitro- cellulose into grains and moistening them with ether alcohol for the purpose of hardening the grains. I had the advantage of seeing’ this manufacture and some experiments with this powder in 1883, in which year also Oscar Wolff and Max von Forster published and patented ® the method of coating small cubes of gun cotton with a solvent for the purpose of keeping them permanently moist. Mr. Reid’s powder is manufactured under the name of E. C. powder, and is still a favor- ite sporting powder, but, being what is now called a bulk powder, namely, a powder of very loose structure and low volumetric density, it was too violent in its effects for military rifles, while for sporting rifles it was just the right thing. I would again mention here that in the beginning of 1886 I suggested to Professor Hebler, the well- known Swiss pioneer of the small-bore rifle, the use of a piece of blast- ing gelatin as a charge for a rifle cartridge,’ but that the very idea frightened him, although he wished to have a pellet of compressed gun cotton from, me for the purpose. Vieille in 18867 thoroughly gelatinized nitrocellulose and made sheets of it, which he cut up in strips or small lozenge-like squares. This was the first military smokeless powder. It has been said that Vieille made his discovery while trying to make a bulk powder similar to E. C. powder, but I have it from him that his invention was the outcome of prolonged study and experiment. This impartial survey shows that while the merit of making the first powder-like material from a nitro compound belongs to Hartig, and while Schultze made the first commercial powder, yet the inven- tion of a gelatinized powder in the modern sense must be attributed to Friedrich Volkmann, although, independently of him, Reid rediscov- ered, twelve years later, a hardened sporting powder, and Vieille, six- teen years later, a thoroughly gelatinized military powder. Nitroglycerin-nitrocellulose powder was invented by Alfred Nobel in 1888,° who gave it the name of ballistite. The British Government adopted a powder which contained insoluble gun cotton with nitro- glycerin and vaseline, the whole being dissolved in acetone.’ Ballis- tite is the service powder in Italy and is much used for large guns. Aniline is now added, and it is claimed both for vaseline, aniline, and diphenylamine that they exert a great stabilizing influenze on the powder. ¢ British patent No. 619, of 1882. b1d., No. 3866, of 1883. ¢ Journal of the Society of Chemical Industry, 1894, p. 575. @\Mémorial des Poudres et Salpétres, 1890, p. 9. e British patent No. 1471, of 1888. fId., No. 5614, of 1889. PROGRESS IN EXPLOSIVES—GUTTMANN. 985 There is no need for me to detail the manufacture of powders. Nitrocellulose powders are made from dry nitrocellulose, in a mixing machine, using a solvent (generally ether alcohol or ether acetone). In many factories the nitrocellulose is made anhydrous by soaking it in alcohol, and then squeezing it out in a press. Some think that the quality of the powder is affected by this method. Some have found a loss of substance up to 5 per cent to take place with certain nitrocot- tons. The mixture is then rolled under a pair of heavy rolls into sheets of the required thickness, cutting them up into squares, and afterwards drying these. In some services ribbons are used instead of grains, and in others threads or tubes are made of such powder and cut into sticks of the length required for the charge. In Ger- many camphor was formerly added to the powder while kneading it. Some countries leave a certain amount of the solvent in the powder, and formerly in France a little amyl alcohol was added, while now diphenylamine has been adopted; this was already used in 1889 in Germany for C/89 powder made by the Cologne-Rottweil factory. Ballistite is made in a different way. Soluble nitrocellulose in the shape of a fine powder is suspended in fifteen times its own bulk of water and nitroglycerin added, the mixture being stirred by means of compressed air. This causes the nitroglycerin to dissolve up the nitrocellulose, the water acting as a carrier only. The paste result- ing in this way is then brought under steam-heated rolls, weighted to exert a pressure of 100 atmospheres, to thoroughly incorporate it, and then mixed by rolling the sheets over and over until they are quite satisfactory. The sheets so obtained are then cut up into flakes, cubes, strips, ete., as required. You will readily understand that every weapon may, and generally does, require a different powder in order to give the desired velocity and not to exceed the permissible limits of pressure. It is obvious that it would be very easy to alter the composition in every case, but as a matter of course such an expedient would be quite unde- sirable alike from a manufacturing and from a service point of view. Hence already in the days of black powder it has been the custom to vary the shape and size of the powder. We thus have rib- bons in France, strings in Great Britain, flakes and tubes in Germany, cords of square section in Italy, short multiperforated cylinders in the United States, cubes from ballistite, spiral sporting powder in Germany, the poudre peigne (spiral powder with comb-shaped in- cisions) of French inventors, ete. Further, these powders may then be made in various lengths, breadths, or thicknesses, and with various kinds of holes, incisions, ete. It is quite impossible to generalize and to say that a particular form is good or bad, because it probably does suit a special weapon. It is a fact that up to a certain size round 286 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. grains are most likely to give good combustion, and that cord or tube comes next; on the other hand, a flat ribbon is likely to burn more uniformly, although, again, a variation in the rate of combustion at different intervals of time may just be what is wanted. The conviction has grown of late that in addition to being smoke- less a powder should also be flameless, so as not to disclose the posi- tion of an attacking force. The military powders suffer, in the first instance, from irregular shooting. In the case of sporting powder, it is necessary to carry out shooting tests with every small batch, because the reputation of a firm depends on keeping powder out of the market which is in the shehtest degree deficient. Careful blending has to be resorted to in order to obtain absolutely uniform results throughout. Of other difficulties in manufacture I will mention only a few. The treatment of a powder under rolls is to a certain extent guided by rule of thumb. It is all very well to look through the paste, the sheet may appear quite transparent to a good and experienced eye, yet small nodules of nitrocellulose may have escaped solution for a long time. The constant crackling heard when rolling thin sheets plainly points to such isolated and undissolved fibers. Incorporating in a kneading machine does not improve matters. Pressing powder out of a die gives very good results with small diameters, but with larger diameters very much depends upon the shape of and the wear on the nozzle, its position among several others or relatively to the die, and on whether the outer skin will contain air bubbles or be cracked. If too much solvent is taken, or the proportions of a com- posite solvent are not quite suitable, the density and uniformity of the powder will suffer. One of the greatest difficulties lies in the proper drying of powder. The smaller sizes of sticks, ribbons, tubes, etce., are easier to deal with. The larger and thicker ones, however, some- times require months to dry properly. With some powders this defect is to a certain extent avoided by leaving some of the solvent behind, but then, of course, we have on the one hand the difficulty of not knowing exactly when the correct amount of solvent is present, and, on the other hand, a certain amount of risk in that the powder would in course of time undergo changes by gradual evaporation of the solvent. Sporting powders are of two kinds, the so-called “ bulk ” powders, consisting of loose granules, coated or hardened by means of a solvent, and the so-called “ condensed ” powders, gelatinized through- out, and made in practically the same way as military flake powders.* The former are supposed to just fill a cartridge used in the old black- “The micro-photographs reproduced on plates 5 and 6 were kindly prepared by Mr. Henry de Mosenthal, Smithsonian Report, 1908 —Guttmann. PLATE 5. Fic. 1.—SMOKELESS BULK POWDER SEEN UNDER THE MICROSCOPE IN ORDINARY LIGHT. Fic. 2.—SMOKELESS BULK POWDER SEEN UNDER THE MICROSCOPE IN POLARIZED LIGHT. - Smithsonian Report, 1908.—Guttmann. PLATE 6. Fic. 1.—SMOKELESS FLAKE POWDER SEEN UNDER THE MICROSCOPE IN ORDINARY LIGHT. Fic. 2.—SMOKELESS FLAKE POWDER SEEN UNDER THE MICROSCOPE IN POLARIZED LIGHT. PROGRESS IN EXPLOSIVES—GUTTMANN. 287 powder gun; the latter are made for modern weapons. The usual “bulk” powders are composed of soluble nitrocotton mixed with potassium or barium nitrate, and generally worked up in an in- corporating mill or drum. The mixture is then either sprinkled with water in a rotating drum, so as to form grains, or extended on a shaking table making short and rapid oscillations. Alternatively it may be put into an hydraulic press and then broken into grains, the solvent being in every case sprinkled over when the grains are already formed. The “ condensed ” powders are. usually made by rolling the “ paste ” into very thin sheets (0.1 millimeter and less), which are then cut into small flakes to obtain the requisite rapidity of combustion. Such powders are dried fairly quickly, and they may sometimes even be boiled in water to promote elimination of the solvent. Since 1800, when Howard invented fulminate of mercury, and since 1815, when Joseph Egg made the first cap, but little progress has been made in the manufacture of these articles. It is still the usual cap and the usual detonator, the only difference being that potassium chlorate enters partly into the composition of detonators, whilst for smokeless powders a hotter flame is found essential, and is obtained by adding a combustible substance. Aluminum powder, either mixed with the fulminate or pressed in a layer on top of it, has been successfully employed. The Rheinisch-Westfiilische Gesell- schaft of Troisdorf make now detonators of tetranitromethylaniline (called tetryl).” It is said that quite half of all the detonators at present manufactured in Germany are made with trinitrotoluene. The manufacture of fulminate of mercury is performed in almost the same way as that described fifty years ago. The increasing demand for ammonium nitrate safety explosives has resulted in the use of greater quantities of powerful detonators. For the same reason great progress has been made with electric deto- nators. Formerly high-tension fuses fired by frictional electric machines were almost solely used, and Breguets were the only low- tension fuses employed in mines. Nowadays the tendency is to use low-tension fuses and magneto-firing apparatus, thus greatly reducing the risk of firing the pit gases. Bickford’s invention still holds the field as regards safety fuses. I have explained in my first lecture wherein the few improvements consist that were made on safety fuses. It is curious that all attempts to make a safety fuse with a core of smokeless powder or some other nitro compound have so far been unsatisfactory. It seems impossi- ble to insure uninterrupted burning. Of late, rapid-burning fuses “British patent No. 28366, of 1904. 51d. No. 13840, of 1905. 288 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. were introduced, some being fired in groups by means of pistols and other central-firing arrangements. General Lauer and Mr. Tir- mann introduced friction fuses, which are fired by means of wires from a distance, and are extensively used chiefly in Austrian coal mines. Girard made “ cordeaux détonants ” by filling lead tubes with nitrohydrocellulose and then drawing them out to the diameter of an ordinary safety fuse. In 1906 these fuses were filled with melinite. and now trinitrotcluene is also used, which permits the employment of lead tubes instead of the costly tin tubes indispensable with a picric acid explosive. The most perfect fuse of this kind is, how- ever, the instantaneous fuse invented by General Hess and introduced into the Austro-Hungarian service. Originally it consisted of a mercuric fulminate core on four threads. In 1903 Hess “ phlegma- tized ” the fulminate ” by the addition of 20 per cent of hard paraffin, but a number of such fuses, tied together by knots, can be detonated by a common detonator, thus replacing electric shot firing and dis- pensing with a detonator in each bore hole. The fuse can be cut, hammered, squeezed, etc., without danger. The more industry progressed all over the world, the greater the coal consumption became, and the more frequently occurred those appalling mine disasters which from time to time convulse public feeling. The British Government was the first to nominate a fire- damp commission. Then followed commissions in Prussia, France, Saxony, and Austria, but not one of them tried a safety explosive before September, 1885. The Prussian Government, however, had built a testing station and trial gallery at Neunkirchen, in the begin- ning of September, 1885, under the direction of Mr. Margraf. In September, 1887, a carbonite consisting of saltpeter, cellulose, nitro- glycerin, and sulphureted oil was found to be absolutely safe. In 1886 Margraf tested securite against carbonite, and this also was found safe. In April, 1887, roburite and kinetite were tried, and in August, 1887, soda dynamite. Thus carbonite was really the first safety explosive. It is necessary to distinguish between explosives which are safe in manipulation (handhabungssicher) and such that are safe in fire damp (wettersicher). The latter only are called safety explosives in this country. The obvious question is, What makes an explosive safe in fire damp? I confess that, having most carefully examined the views of those most competent to given an opinion, I fail to find a definite answer. At one time the Prussian commission stated that the more rapid the explosion the safer the explosive, and some color is lent to @ Artilleristische Monatshefte, August, 1908. +b“ Mittheilungen tiber Gegenstiinde des Artillerie und Geniewesens,” 1907, p. 115. PROGRESS IN EXPLOSIVES—GUTTMANN. 289 this theory by the fact that fulminate of mercury does not ordinarily ignite fire damp, whilst black powder always does. The theory is, however, controverted by certain black-powder mixtures, foremost among which is bobbinite, which is safe up to a certain point, and by nitroglycerin and blasting gelatin, which are not. The French Government commission stated that an explosive whose temperature of explosion was below 1,500° C. could be licensed for use in fiery mines. Curiously enough carbonite, so far the safest of all, and several others, which are licensed for such use, have a tem- perature of explosion considerably higher than 1,500° C. Mr. Bichel, in conjunction with his collaborator, Doctor Mettegang, says that the velocity of detonation, the maximum temperature of the products of combustion, the length and the duration of the flame of an explosive all influence the safety of an explosive adversely.* He considers, and in the author’s opinion very justly, the nature of the products of combustion to be all important, whether they censist of solid particles which remain incandescent for a considerable time, or of large quantities of combustible gases shot forward with great force. In this way he corroborates early attempts to photograph the flame of an explosion made by Schoeneweg, the inventor of securite, and by Siersch, of Pozsony. The velocity of detonation can not, how- ever, be considered to be a determining factor under ail circum- stances. Certain nitroglycerin explosives, amongst which we may also include carbonite, explode much more rapidly than. say, bob- binite, and yet show themselves to be much safer when tested. I myself have found that up to a certain point the addition of picric acid gave increased safety on test. It will be remembered that the British commission found a water jacket round the charge very efficient. Sodium carbonate, mag- nesium sulphate, and other substances were tried, either separately in front of the explosive or as ingredients. More prominence was then given to the French recommendations, and the notion became prevalent that the addition to the explosive must be a flame-cooling agent in the shape of water vapor or some other heat-absorbing gas. Thus permanganate, bichromate oxalates, and other salts were used, and of late common salt has sprung into favor. The only definite result obtained so far is that ammonium nitrate is absolutely safe in all quantities, and that cellulose and similar substances in nitroglycerin compositions—e. g., rye flour in car- bonites or wood pulp in other explosives—renders them highly inert in fire-damp mixtures. Ammonium nitrate can not, however, be used by itself, although Lobry de Bruyn succeeded in exploding it,” and therefore some combustible substance must be added. It simply @ Gliickauf, 1904, No. 35. +6 Recueil des travaux chimiques des Pays-Bas, 1891, p. 127. 290 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. remains to be determined what minimum quantity of such combustible can be added to avoid flames of great length and duration. The next question is, How can one tell whether an explosive is “safe”? This question is a still more difficult one to answer. The various governments and also certain factories have erected testing stations. These stations generally consist of a long wooden or iron tunnel, round or oval in section. The explosive is shot into a gas mixture. In this country a ballistic pendulum is used to ascertain the quantity of the explosive equal in force to 4 ounces of dynamite No. 1, and this quantity with a stemmed shot is then fired in air con- taining 15 per cent of coal gas. If the mixture does not fire in 20 shots the explosive is considered a safe one. In most other countries the quantity of the explosive in question is determined which will fire and that which will just not fire a certain pit gas mixture. This gives.us what Mr. Watteyne, the well-known Belgian authority, calls the “ charge limite” of an explosive. This latter way is certainly the more rational one, since it permits of comparison between different kinds of explosives. Is this method of testing, however, above re- proach? TI think not, although I know of no better one at present. It has been found that the narrower the bore of the cannon the easier ignition takes place under certain circumstances. The Woolwich circular section gallery, which has a sectional area of 0.36 square meter, is much more sensitive than the elliptical Belgian one, whose sectional area is 2 square meters, and, in fact, even with equal diam- eters each gallery may be said to have its own ignition temperament, which affects the results. Thus quite recent tests at Frameries in a gallery having a sectional area of 0.28 square meter showed that two safety explosives, whose charge limite was 900 and 450 grams, re- spectively, fired at 300 and at 75 grams. The gas used also exerts considerable influence on the tests. It has been known for a long time that coal dust as well as pit gas is highly explosive: I believe that Engler, when investigating explosions in the charcoal heaps of the Black Forest,* was the first to show that mixtures of coal gas and air, so poor in gas as to be non- inflammable, were rendered explosive by the addition of some char- coal dust. The Mining Association of Great Britain took the lead, experimentally investigating the influence of coal dust on explosions in mines. An iron shell 7 feet 6 inches in diameter and 1,083 feet long was used to carry out the experiments. So far it has already been ascertained ° that two zones of stone dust on either side of a zone of coal dust arrested the path of a flame, and that unless the coal- dust zone exceeded 180 feet in length, no explosive force was mani- 4 Chemische Industrie, 1885, No. 6. 4“ Coal dust experiments,’ The Times, September 24, 1908. HE, 7h PLATE 7. TESTING STATION AT FRAMERIES (END VIEW). Smithsonian Report, 1908.—Guttmann. Smithsonian Report, 1908.—Guttmann. PLATE 8. TESTING STATION AT FRAMERIES (VIEW OF THE INTERIOR). PROGRESS IN EXPLOSIVES—GUTTMANN. 2991 ' fested. Might I submit an old idea, which I base on some patents of mine that have proved highly useful? An absorption tower retains solid particles contained in a gas mixture, and also cools the latter very efliciently, and one of the best methods for absorption has proved to be the production of a fine spray or mist of moisture. It seems quite feasible to utilize certain lengths of tunnel for the construction of inverted absorption towers at intervals, and certainly at every point where a side gallery runs into the main or haulage roads. So much seems certain to me from the study of the results of past inves- tigators that a small addition of coal dust will be found to promote the explosion of poor gas mixtures, and that, therefore, a separation of the dust from the gas will in some cases prevent an explosion. Lacking definite knowledge as to what renders an explosive safe in fire damp, and how this is to be ascertained, it would be natural to seek a solution in practical results. The sale of an article does not always depend upon its real value, but very frequently on the way it is advertised and pushed, whether it is made in the country of con- sumption or not, whether it possesses disadvantages that render an- other less efficient article a preferable one, etc. In spite of this it is not unfair to assume that the statistics showing the quantities of safety explosives actually consumed in a great coal-producing coun- try like Great Britain have a real bearing on the question as to which explosives have given a reasonable amount of safety. The report of the inspectors of explosives for 1907 gives the following highly instructive figures: Out of a total consumption of 7,764,122 pounds, were used, of saxonite, 1,721,193 pounds, or 22.18 per cent, and of bobbinite, 1,063,111 pounds, or 13.69 per cent. Saxonite contains a large percentage of nitroglycerin. Bobbinite is a black powder mixture. From the inquiry on bobbinite? the following table regarding accidents in coal mines caused by various safety explosives in 1904 and 1905 is calculated : Con- sump- Accidents. Killed. Injured. tion. Per cent. | Number. | Per cent. | Number. | Per cent. | Number.| Per cent. Bobbinitenspecesre sas ech. oe eae 13. 69 20 17. 54 Ps 8. 33 30 18. 87 Other permitted explosives. .... | 86. 31 94 82. 46 22 91. 67 129 81.13 It will thus be seen that a black powder mixture like bobbinite, which would not be licensed in any other country and be condemned without trial, ranks second in consumption, being used to the extent * @ Report of the departmental committee on bobbinite, London, 1907. 292 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. of 13.7 per cent of the total consumption, while saxonite, a nitro- glycerin explosive, ranks first, with 22.18 per cent of the total. Am I therefore right in saying that we have succeeded in making the use of explosives in coal mines infinitely more safe than before, but that we do not really know why ? ; LV: Nitrocellulose has found a greater sphere of use for purposes other than smokeless powder or dynamites. The celluloid industry, introduced by the Brothers Hyatt, and more recently the artificial silk industry, consume enormous quantities. Of celluloid the United States produce about 4,000 tons per annum, Germany 15,000, and the rest of the world about 5,000 tons, of which yearly total of 24,000 tons this country produces about 2 per cent. This necessitates about 14,000 tons of nitrocellulose per annum. Of artificial silk, about 5,000 tons are made annually, though only about 200 tons in Eng- land.¢. The amounts used for varnishes like pegamoid, fabrikoid, etc., for making or steeping incandescent gas mantles, for water- proofing solutions, for patent leather (nitrocellulose dissolved in amylacetate, and mixed with aniline black) and for photography are also considerable. The solubility of the nitrocellulose in a definite mixture of ether alcohol to the extent of 2 per cent either way is by no means unimportant, as this may mean 10 per cent more of very expensive solvent. When you consider that one of these factories, which I had oceasion to revisit quite recently, makes as much as 3,000 kilograms of silk a day, you will have some idea of the sums involved. In neither of these cases is the nitrocellulose pulped, but the whole of the fiber is dissolved. I am afraid purification is sometimes not carried as far as it ought to be with due regard to the stability of the finished celluloid. In the case of artificial silk the fact that the nitrocellulose is denitrated seems to indicate that thorough purifica- tion is unnecessary, but the silk fiber made from well-stabilized nitro- cellulose will be found to possess inherent good properties of its own. The same may be said of varnish, although in this ease a slight acidity at certain stages of the process has the advantage of rendering the nitrocellulose more readily soluble. The manufacture of these nitrocelluloses also varies in other re- spects. In dealing with such large quantities everything is carried out expeditiously and without much handling. The nitrocellulose for 4 According to Dr. Richard Schwarz, there are at present in Europe 30 fac- tories making artificial silk, and the world’s production in 1907 amounted to 3,300,000 kilograms, of which 1,500,000 were nitrocellulose silk, 1,800,000 “ Glanzstoff,’”’ and 500,000 viscose silk (Neue Freie Presse, Vienna, January 5, 1909). PROGRESS IN EXPLOSIVES—GUTTMANN. 293 artificial silk is not fully dried, but from 12 to 30 per cent of water is allowed to remain in it. For the sake of completeness mention must be made of the pro- posed use of explosives for motive power. I well remember having shown me at Vienna, in 1878, an engine to be worked by small charges of dynamite. In order to show the absence of danger the inventor had made the model entirely of wood. Again, quite recently my advice was sought regarding the application of smokeless powder to flying machines. Several patents referring to motors and com- pressors driven by explosives have been taken out, and one of them quite recently.¢ An account of progress on explosives would be incomplete without mention of the conditions under which they are manufactured. The late Col. Sir Vivian Dering Majendie deserves lasting recogni- tion for having created that most excellent explosives act of 1875. The influence of this act, and perhaps almost to the same extent of the annual reports of the British inspectors of explosives on the arrange- ments and construction of buildings and machinery, the general clean- liness of the operations performed, and the security of workmen against accident can hardly be overrated, and the example set in this country has been followed all over the world. In arranging buildings due consideration is now paid to the dan- gers present on account of the nature of the operation and the quan- tity of materials dealt with. The advent of high explosives has unfortunately made us acquainted with effects of explosions unknown in the old powder days, and in order to counteract these effects the author recently suggested ’ the construction of danger buildings in a special kind of ferro-concrete. The buildings are so designed that pieces of burning débris can not penetrate their roofs, and so bring about their destruction. At the same time the shock of the explosion transmitted from a distance through the ground will not cause the walls to open out. This proposal has been very favorably received by a number of manufacturers, and in several instances has already been adopted. The armoring of such a building forms a Faraday’s cage, and renders the whole structure hghtning proof. This is of importance, since the regulations governing the erection of lightning conductors have not increased the safety of buildings to any great extent in spite of lightning-rod conferences and investigations. Mag- azines which were satisfactorily tested on the very day of a thunder- storm have been blown up, and nothing short of a cage, or at least a “British patents, Nos. 961, of 1874; 24742, of 1904; 28376, of 1904; 22125, of 1905. ®’“ Explosions and the Building of Explosives Works,” Journal of the Society of Chemical Industry, 1908, No, 13. 294 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. complete system of conducting network over and on the buildings, seems to be efficacious. Despite all precautions disasters of great magnitude will occur in modern explosives works. This is, no doubt, in the first place, due to the fact that quantities are nowadays made in such works which were not dreamed of thirty years ago. For instance, the works at Modder- fontein and Somerset West produce annually over 10,000 tons of dynamite, and several other works run them very close. Such an enormous output requires a very considerable number of buildings, and consequently the chance of damage to life and property is greatly increased. The construction of factories has, on the other hand, pro- ceeded on somewhat orthodox lines, and not always, nea, with due regard to subdividing and minimizing risks. Another reason for such catastrophes is the want of appreciation of certain inherent dangers. The author has always warned manufac- turers and users alike that the function of an explosive is to explode, and that although certain compositions are almost insensitive to ordi- nary impulses, such as blows, friction, ete., yet he never believed that any explosive existed which under favorable conditions and by proper means could not be made to explode. It is true that continental rail- ways carry certain explosives, like ammonium nitrate mixtures, by ordinary goods train, and the author believes this to be an example which might be quite safely followed by British railway companies in the best interests of the public. There is no danger attached to any of these explosives when in the safe custody of a railway van, and when they do not come into contact with dangerous goods. Yet another warning to manufacturers may not be out of place. Special attention must be paid to prevent any accumulation of dirt in places liable to exposure to heat. In the French powder factory at Saint-Médard the explosion which occurred in 1891 could be clearly traced to gun-cotton dust lodging in the joints and cracks of a wooden workshop.? Do factories even now take every precaution to prevent the accumulation of dirt of this kind? The author has reason to doubt it, and a clean-up at a factory which he witnessed a short time ago was quite an eye-opener. He can only warn those concerned that every building where explosive dust can be produced, and every ap- pliance and utensil therein, should be periodically and thoroughly cleansed and overhauled. Imagine a drying tray, covered underneath with canvas, on which gun cotton or powder is dried all the year round, and ask yourselves what the chemical stability of the dust may be after a year’s exposure to a temperature of 40° C. (some factories dry at 50° C.), and whether a material dried on such a tray is fairly treated. 4@Mémorial des Poudres et Salpétres, 1894, p. 7. “ALAYONOO-OHNS4 NI LIING GNNO|] GNV dOHSHYHO/MA SSAISO1dxXy needy et => =) “> —y = - mee yp pee, % oh = 2 - GY a ee x3 FENG Wee a 29 =r Deon eZ Uz : POP OoPn Ecte. Ue Da ma sala OPE unk a igs “ < a eee En WAS - f Ch - ee exh O08? ~~ tu PoE Sy poate Lely. 7 Preis ¥ ? 7 oO le 8 \ / Pac "a a je a = = CES PPS ieee Sa 4g yf ups Sy , oy ai \ = ih aX = SNS ee ee eel aaa 4 : = ROS 1 1 —§ % c 3 ° = £ e 2 . Ginetta COR tases S N AE Da a ed TA a AP EEG AG a TETRA RTA eee le oe eoorecee IL Lg LLL YSUTA 7 thle aM aan Ty Dunner Gar Cay guar men SAY ay Ghee ge Stal teen Sia AD ssnonte Oe Ultras Te, IEONO ui/im 00, Spurnoy wfus gy ~_* GALLE eee ceccccscores TT Dee a i CLL ‘6 3LV1d “UURW}NH—'gO6| ‘Woday ueiuosy}iws PROGRESS IN EXPLOSIVES—GUTTMANN. 995 Nowadays an explosives factory seems inconceivable without elec- tric light and small motors near buildings or on machines, while even the operation of drying sensitive compositions is performed by elec- tric resistances serving as a perfectly adjustable source of heat. Modern explosives have, on the other hand, introduced electrical dangers themselves. In the first lecture the possibility of firing a press charge of black powder by static electricity collecting between ebonite press plates was mentioned. Nitrocellulose is electrified by the current of warm air passing over it when drying, and the neces- sary earthing arrangements were first proposed by Mr. Walter F. Reid, and in many cases especially designed by the author. Mixing machines for blasting gelatine and smokeless powder, especially those provided with reversing gear and belts running in opposite directions, have been known to give long sparks unless properly earthed. This was remedied at Waltham Abbey by saturating the belts with glyc- erin. The powder itself during manipulation will generate elec- tricity. Ether vapor given off from smokeless powder and mixed with air can be fired with a very small spark, and special care should be taken in preventing its formation. The manufacture of high explosives seems a simple operation even to experienced chemists, and the danger attending the process ap- pears to be the only difficulty. As a matter of fact, it bristles with difficulties. A good many have already been mentioned, and a few additional and special points are worthy of note. Glycerin is a uniform, easily purified substance, and its nitric ester, nitroglycerin, although sensitive to a blow, especially when frozen, is a chemically stable explosive, tame and harnessed for the service of man. Most nitro compounds of the aromatic series have very great chemical stability. Picric acid is a treacherous substance. It is very powerful, but that is its only recommendation. Those who use it may be asphyxi- ated by the fumes of a prematurely exploding shot; those who are fired at sometimes rejoice when it fails to explode. It requires special mixtures to avoid melting at high temperatures, and it attacks its metal container, forming a dangerous picrate. As an ingredient of other explosives it is useless, since on account of its acid properties it reacts upon the other ingredients. Moreover, it is capable of dis- placing other acids, such as nitric acid in nitrates, a disagreeable property which some patentees have found out to their cost. With Montaigne, “ I hope that we shall one day give up its use.” A more inconvenient material still is nitrocotton. As already stated, cotton is one of the most complex substances known, and for some unexplained reason we have been in the habit of using it after an ill-treatment following upon an undesirable state of cleanliness. At the best, however, we have an almost uncontrollable substance in 88292—sm 1308 20 296 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. nitrocotton. It is in such a loose state of equilibrium that the slight- est reaction will upset its balance. No wonder that when nitrocellu- lose is mixed with another explosive like nitroglycerin to form smoke- less powder it becomes less reliable, and acts detrimentally on the nitroglycerin. This is accentuated still more in the presence of another disturbing factor, such as heat or an alkali. It is a fact that any alkali, however weak, will gradually saponify the nitrocellulose, and although dangerous decomposition would rarely set in, a bad heat test may result and cause the nitrocellulose to be destroyed by the authorities. Chalk in water is no exception to this action. The case is very much aggravated by the action of heat. It is well known that properly purified guncotton has been stored in all climates without giving rise to alarming decomposition, even when the temperature was above the normal. Nitroglycerin and _nitro- cellulose, both of which will by themselves give a potassium iodide heat test of, say, twenty minutes, may, however, when mixed, not stand more than ten minutes. It is a convenient excuse to say that this is due to an alteration of the physical state, but no proofs have been given for such an assertion, and I should be curious to hear of them. The amount of nitrous acid required to color the test paper is so small (according to Will@ it is only 4X 10° milligrams, equivalent to 0.0000016 per cent, or about 1 in 60,000,000 for a sample of 2.5 grams) that whatever its physical state, there would always be enough material exposed on the surface to give off this quantity of gas in regulation time if the explosive were of a low order of stabil- ity. There is much more justification for supposing that a chemical reaction goes on between the nitroglycerin and nitrocellulose at the elevated temperature of the heat test (82° C.), the nitrocellulose being first decomposed, and the nitrous gases developed reacting on the nitroglycerin and thus accelerating the decomposition. We next come to the treatment a powder undergoes during manu- facture. Whether passed under steam-heated or high-pressure rolls, whether kneaded for hours in a mixing machine, squeezed from a die with an unnecessary amount of pressure and friction, due to a defect in or bad construction of the die, whetber it be dried for weeks and months at temperatures far above the normal, everything tends to destroy the equilibrium of the nitrocellulose. Years ago the author showed that there is a critical point for mixtures, such as blasting gelatine or smokeless powders at or about 45° C., yet during manu- facture this temperature is frequently approached and sometimes exceeded. @Dr. W. Will, “Untersuchungen iiber die Stabilitiit von Nitrocellulose 2. Mitteilung. Der Grenzzustand der Nitrocellulose in quantitativer Beziehung,” Neubabelsberg, 1902, p. 28. PROGRESS IN EXPLOSIVES—GUTTMANN. 997 In some countries the heat test is still carried out at a temperature of 65° C., and if the explosive stands it for, say, thirty minutes, the result is considered satisfactory. Yet how often have we seen this temperature attained during manufacturing operations, and main- tained for hours! Is this reasonable ? We will assume now that we have taken every precaution to manu- facture an explosive which, as regards purity of its ingredients and as regards care in its preparation, leaves nothing to be desired. We were told everywhere until about ten years ago, and are still told so in this country, that the explosive must be heated to a temperature varying from 65° to 82° C. without developing sufficient nitrous acid fumes within, say, ten minutes to color potassium iodide paper. The vagaries of this test are very amusing. Eleven years ago“ the author was the first to show how it could be masked and falsified. The potassium iodide paper itself is an uncertain factor. Great precau- tions must be taken in its preparation, while the thickness of the paper is such a disturbing factor that the papers from one official source give a test nearly double those from another. Various other tests on similar lines have been proposed to replace the potassium iodide test, but not one of them is a true test of stabil- ity. The potassium iodide, or the diphenylamine test, if always car- ried out under identical conditions, are good enough as a rough check on the manufacture. They do not, however, show whether the ma- terial itself is so constituted as to remain stable. This is, perhaps, of small importance in the case of nitroglycerin or an aromatic nitro- compound with their relatively simple structure, but it is all im- portant for nitrocellulose, where the heat test in the opinion of most. . experts is of little value as a criterion of the finished article. In order to judge of stability, the critical point at which an explosive breaks down must be found, and it is also necessary to determine whether decomposition proceeds regularly or at a dangerous and increasing rate when this point is passed. A number of tests have been proposed to fulfill these conditions. They are all based on the principle that a small quantity of explosive is heated to a temperature which causes decomposition comparatively quickly yet gives sufficient time to dif- ferentiate results. In France this temperature was 110° C., but all the modern so-called “ destruction” tests are made between 130° and 135° C. All these tests require a considerable amount of time and constant supervision by a chemist. A rapid and reliable method is to heat the explosive in long glass tubes immersed in a bath of amyl alcohol provided with a reflux condenser, and to note the time that elapses *The Chemical Stability of Nitro-compound Explosives, “Journal of the Society of Chemical Industry,” April 30, 1897. 298 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. before a distinct coloration in the tube is observed. This method com- pares very favorably with all others. As I frequently mentioned, the duration of the heat test is prac- tically halved by a rise in temperature of 5° C., and Will has con- firmed this by proving that the volume of gases evolved is doubled at the same time. This is, however, only correct for temperatures above 45° C., the critical point for nitrocellulose. Below 40° C. the durability of an explosive properly prepared with it increases exceed- ingly rapidly, and it may be safely assumed that under 20° C. its stability is permanently assured. This contention has been proved in practice. The author does not. know of a single authenticated instance of decomposition in an ex- plosive magazine where the temperature has been kept within the permissible limit. This simple precaution was, however, neglected in a good many instances by both naval and military authorities. It was and still is the practice in men-of-war to arrange the ammunition stores and powder magazines in close proximity to boilers and engines, fre- quently without any ventilation, whilst at times explosives of all kinds are stored together. Iourteen years ago the author discussed this arrangement, and drew attention to the dangers arising there- from. A dozen explosions on men-of-war and a disaster like that on the Jena occurred before an alarm was raised, and now all navies are hurriedly installing refrigerating apparatus. This is all very well as far as it goes if the machinery does not break down at the critical moment; but can not designers of war ships find another place for ammunition? Why go to the length of all sorts of precautions when it should not be impossible to remove the cause of deterioration altogether ? This misplacing of ammunition stores is only slightly mitigated by the fact that twenty years ago the manufacture of smokeless powders had only just begun, and nobody knew much about them. Worse than this, however, was the action of many governments in at once erecting their own powder works, without any experience in the manu- facture of nitrocompounds to go upon, and relying entirely on what private manufacturers cared to show them, and on what they them- selves could find out by experiments. Some of their powders made fifteen and twenty years ago are still in service, and are now the objects of suspicion. It is, nevertheless, not fair to throw the whole of the blame on the explosive charge. How would the priming and detonating composi- tions used in gun charges and shells behave under unfavorable cir- cumstances? Fulminate of mercury, potassium chlorate, sulphur, antimonypentasulphide, picric acid, and other chemicals are con- 4 Journal of the Society of Chemical Industry, 1894, p. 588. PROGRESS IN EXPLOSIVES—-GUTTMANN. 299 tained in such compositions, and it is open to question whether proper tests are always carried out as regards their purity and stability under all conditions. Fearing the lack of stability in smokeless powders, which in the early days of their manufacture was not without justification, in- ventors began to look around for so-called “ stabilizers,” that is to say, additional ingredients, which would neutralize the nitrous acid liberated on decomposition. Some people thought that if a little ether alcohol was left in the powder it would act as a stabilizer, and in order to prevent the rapid escape of the solvent on storage, a little amyl alcohol was added, thus slightly raising the boiling point of the solvent.* As a matter of fact, this would merely constitute absorption of the nitrous vapors, but would not prevent their being given off again on heating. A better plan is the addition of “ stabilizers,” which would form stable compounds with the nitrous acid; for instance, aniline, which the Nobel factory at Aviglana used in their gun cotton twenty-four years ago, and which both they and the Italian Government employ for service ballistite. Diphenylamine and, it is said, vaseline would act ina similar way. The stable compounds formed from stabilizers, like amidoazobenzol and other aromatic nitro compounds, retain the nitrous acid, and thus transform the reaction into a slow and regular one, which keeps the powder in good condition as long as there is any stabilizer left. The length of time a powder remains in good condi- tion will therefore only depend on the proper constitution and manu- facture of the powder. Stabilizers, like diphenylamine and aniline, will also reveal their presence as soon as the powder goes wrong, since the compounds formed with them by the action of nitrous acid show as spots or stripes of peculiar colors, varying either in shade or intensity as de- composition progresses. Since the French commissioners on the Jena accident emphasized this fact, already known in Germany and Italy, everybody speaks of “ révélateurs,” the addition of an indicator, as being a panacea. Asa matter of fact the author considers it only a needlessly alarming arrangement, like an alarm thermometer, and unnecessary with a good powder stored under proper conditions, but which would cause commanders of warships to nervously watch their stores after the faintest indication, without giving them any remedy in midocean. The whole idea is not new, having been patented by Nicholson and Price in 1871.® What we must aim at is an explosive which is durable and stable under all ordinary conditions of use, and even under some extraor- *Chambre des Députés, “Rapport sur les causes de la catastrophe de Jena,” Paris, 1907. ® British patent No. 2430, of September 15, 1871. 300 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. dinary ones, just as in the case of the old black powder. In the author’s opinion, and his view is shared by very eminent colleagues, there can be no doubt that nitrocotton (and for the matter of that any other nitrocellulose) is not a suitable ingredient for a service powder. Having built or reconstructed a number of works and seen quite half of all those in Europe, he ventures to speak with some authority. Let us again recapitulate its defects. Made from a material which is most complex and lable to form unstable com- pounds, we elect to use it in a form which can neither be clean, nor of uniform growth, nor even of constant composition. The conditions of manufacture are such that in the absence of very special precau- tions the nitrocotton retains unstable compounds and is liable to decompose. Under the influence of heat, of certain additions or in- gredients, of unsuitable treatment or friction, the nitrocotton may decompose and react in a progressive manner upon the other ingre- dients. It requires a solvent in order to be brought into a physical state which will permit the rate of burning of the powder to be regu- lated. Such solvent, if volatile, requires prolonged heating to drive it off as completely as possible. This heating helps to shorten the life of the powder, and any solvent remaining behind affects its ballistic properties. Nitrocellulose is not a uniform compound by any means, and it is almost impossible to make sure that every batch shall have the same composition and effect. The latter by no means depends on the percentage of nitrogen being the same, though this condition may be fulfilled by suitable blending. For instance, a mixture of soluble and insoluble nitrocellulose would not have the same effect as a nitrocellulose prepared direct, although each may contain the same percentage of nitrogen. The question will naturally be asked, What will be the powder of the future? If we may venture a prophecy, the future belongs to a stable nitrocompound of the aromatic series, perhaps in conjunction with nitroglycerin. Such nitrocompounds have already been pro- posed, and sooner or later one will be found that meets all require- ments. Although every service will be reluctant to make a change, yet having learned to appreciate the value of scientific research, some government will be sure to make a bold plunge, when all others will soon follow suit. RECENT RESEARCHES IN THE STRUCTURE OF THE UNIVERSE.¢ By Pror. Dr. J. C. KAPTEYN, Director of the Astronomical Laboratory, and Professor of Astronomy in the University of Groningen. INTRODUCTION. I consider it an uncommon privilege to lecture on the structure of the universe in the country of the Herschels. Even now their celebrated gauges are unrivaled, and they still form one of the important elements on which any theory of the stellar system must be based. It is well known that the plan of these gauges consisted in direct- ing the telescope successively to different points all over the sky, and simply counting the number of stars visible in the field. REGULARITY IN THE ASPECT OF THE SKY. There is one fact clearly brought out by these gauges to which I must call your attention. It is that in the outward appearance of our nightly sky, as seen with the telescope, there is a great regularity. In the Milky Way, that belt which we see with the naked eye encircling the whole of the firmament nearly along a great circle, the number of stars, as seen in Herschel’s 20-foot reflector, is enormous. On both sides this apparent crowding of the stars diminishes very gradually and regularly, till near the poles of the Milky Way we come to the poorest parts of the sky. VARIATION WITH GALACTIC LATITUDE. Let us look at this phenomenon somewhat more closely. If we direct our telescope first toward the part of the Milky Way near Sirius, and if from there we gradually work up toward the North Pole of the Milky Way in the constellation called the “ Hair of *VLecture before the Royal Institution of Great Britain, London, Friday, May 22,1908. Reprinted by permission. 301 302 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Berenice,” we shall clearly perceive this gradual and regular change in the number of stars. Now, if we repeat the same process, be- ginning from some other point of the Milky Way, say in Cassiopeia, or the Southern Cross, we shall find that, not only is there a similar gradual change, but we shall approximately go through the same changes. LITTLE VARIATION WITH GALACTIC LONGITUDE. At the same distance from the Milky Way we shall find approxti- mately the same number of stars in the field of the telescope. Put in other words: The richness of stars varies regularly with the galactic latitude; it varies relatively little with the galactic longitude. Imitating most of the investigators of the stellar system, we will therefore disregard the longitude and keep in view only the changes with the galactic latitude. In reality this comes to being satisfied with a first approximation. For, in reality, there are differences in the different longitudes, especially in the Milky Way itself. But even here the differences are not so great as seems commonly to be supposed. There is every reason to believe, therefore, that our ap- proximation will be already a tolerably close one. REAL STRUCTURE. Meanwhile what the Herschel gauges teach us is only relative to the outward appearance of the sky. What is the real structure of the stellar world? If we see so many stars in the field, with the telescope directed to the Milky Way, is it because they are really more closely crowded there, as Struve thinks, or is the view of the older Herschel correct, who imagined that the greater richness is simply a consequence of the fact that we are looking in deeper layers of stars; that our universe is more extensive in the Milky Way than it is in other directions? Imagine that we could actually travel through space. For in- stance, imagine that first we travel in the direction of the constella- tion Cassiopeia. If we travel with the velocity of light, not so very many years would pass before we get near to some star. Proceeding on our journey for many, many more years, always straight on, we will pass more stars by and by. How will these stars look thus viewed from a moderate distance—say, from a distance as that of the sun ? Will they all be found to be of equal luminosity, as Struve prac- tically assumed? And in this case are they as luminous as our sun, or more so, or less sof Or are they unequal ? STRUCTURE OF THE UNIVERSE—KAPTEYN. 303 If so, how many of them are brighter than our sun, how many fainter? Or, to be more particular, how many per cent of the stars are 10, 100, 1,000, etc., times more luminous than our sun? How many are equal to the sun, or 10, 100 times fainter? Or in two words: What is the nature of the mixture? Or, lastly, what is the mixture law of the system of the stars? And furthermore, in traveling on shall we find the stars in reality equally thickly or rather thinly crowded everywhere? Or shall we find that after a certain time, which may be many centuries, they begin to thin out as a first warning of an approaching limit of the system? Is there really such a limit, which, once passed, leads us into abysses of void space ? Herschel thought there was such a limit, and even imagined that his big telescope penetrated to that limit; that is, he assumed that his telescope made even the remotest stars visible. On this supposi- tion is based his celebrated disk theory of the system. Again, we may condense these questions in this single query: How does the crowding of the stars, or the star density, that is the number of stars in any determined volume (let us say in a cubic light cen- tury) vary with the distance from our solar system ? But there is more. We supposed that our journey went straight on in the direction of Cassiopeia, which is in the Milky Way. What if our journey is directed to the Pleiades, which are at some distance from that belt, or to the Northern Crown, which is still farther, or to the Hair of Berenice, which is farthest of all from the Milky Way? For different regions equally distant from the galaxy we have seen that outward appearances are the same. We may admit, with much probability, that in space, too, we would find little differ- ence. Summing up, the problem of the structure of the stellar system in a first approximation comes to this: STATEMENT OF PropLEM—T0 DETERMINE, SEPARATELY FOR REGIONS OF DIFFERENT GALACTIC LATITUDE, IN WHICH WAY THE STAR DENSITY AND THE MIXTURE VARY WITH THE DISTANCE FROM THE SOLAR SYSTEM. 1 think that there is well founded hope that, even perhaps within a few years, sufficient materials will be forthcoming which will allow us to attack the problem to this degree of generality, with a fair chance of success. At the present moment, however, our data are yet too scanty for the purpose. Still, they will be sufficient for the derivation of what must be in some sort average conditions in the system. The method of treatment will not be essentially different from that which will be applied later to the more general problem, but we have provisionally to be content with introducing the two following simplifications: 304 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. RESTRICTIONS. 1. We will assume that the mixture is the same throughout the whole of the system; 2. We will not treat the different galactic latitudes separately. The consequence will be that the resulting variations of density to which our discussion leads, will not represent the actual variations which we would find if we traveled in space in any determined fixed direction, but a variation which will represent some average of what we would find on all our travels if we successively directed them to different regions of the sky. SIMPLIFIED PROBLEM. Our present problem will thus be confined to finding out: (a) The mixture law. | (©) The mean star density at different distances from the solar system. If time allows I will, at the end of this lecture, say a few words on the restrictions introduced and the way, to get rid of them. As it is not given to us to make such travels through space as here imagined, we have to rely on more human methods for the solution of our problem. DETERMINATION OF DISTANCE. It is at once evident that there would be no difficulty at all if it were as easy to determine the distance of the stars as it is to determine the direction in which they stand. For in that case the stars would be localized in space, and it would be possible to construct a true model from which the peculiarities of the system might be studied. Tt is a fact, however, that, with the exception of a hundred stars at most, we know nothing of the distances of the individual stars. What is the cause of this state of things? It is owing to the fact that we have two eyes that we are enabled not only to perceive the direction in which external objects are situated but to get an idea of their distance, to localize them in space. But this power is rather limited. For distances exceeding some hundreds of yards it utterly fails. ‘The reason is that the distance between the eyes as compared with the distance to be evaluated becomes too small. Instruments have been devised by which the distance between the eyes is, as it were, artificially increased. With a good instrument of this sort dis- tances of several miles may be evaluated. For still greater distances we may imagine each eye replaced by a photographic plate. This would even already be quite sufficient for one of the heavenly bodies, viz, for the moon. At one and the same moment let a photograph of the moon and the surrounding stars be taken both at the Cape Observatory and at STRUCTURE OF THE UNIVERSE—KAPTEYN. 805 the Royal Observatory at Greenwich. Placing the two photographs side by side in the stereoscope, we shall clearly see the moon “ hanging in space,” and may evaluate its distance. But already for the sun and the nearest planets, our next neighbors in the universe after the moon, the difficulty recommences. The reason is that any available distance on the earth, taken as eye distance, is rather small for the purpose. However, owing to incredible perseverance-and skill of several observers and by substi- tuting the most refined measurement for stereoscopic examination, astronomers have succeeded in overcoming the difficulty for the sun. T think we may say that at present we know its distance to within a thousandth part of its amount. Knowing the sun’s distance we get that of all the planets by a well-known relation existing between the planetary distances. But now for the fixed stars, which must be hundreds of thousands of times farther removed than the sun. There evidently can be no question of any sufficient eye distance on our earth. Meanwhile our success with the sun has provided us with a new eye distance 24,000 times greater than any possible eye distance on the earth. For now that we know the distance at which the earth travels in its orbit round the sun, we can take the diameter of its orbit as our eye distance. Photographs taken at epochs six months apart will repre- sent the stellar world as seen from points the distance between which is already best expressed in the time it would take light to traverse it. The time would be about sixteen minutes. However, even this distance, immense as it is, is on the whole inadequate for obtaining a stereoscopic view of the stars. It is only in quite exceptional cases that photographs on a large scale—that is, obtained by the aid of big telescopes—show any stereoscopic effect for fixed stars. By accurate measurement of the photographs we may perhaps get somewhat beyond what we can attain by simple stereo- scopic inspection, but, as we said a moment ago, astronomers have not. succeeded in this way in determining the distance of more than a hundred stars in all. How far we are still from getting good stereoscopic views appears clearly from the stereoscopic maps which your countryman, Mr. Heath, constructed, making use of the data obtained in the way pres- ently to be considered. In order to get really good pictures, he found it necessary to increase the eye distance furnished by the earth’s orbit 19,000 times. MOTION OF SOLAR SYSTEM THROUGH SPACE. Are there, then, no means of still increasing this eye distance? There is one way, but it is a rather imperfect one. Sir William Herschel has been the first to show, though certainly his data were 306 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. still hardly sufficient for the purpose, that the whole of the solar sys- tem is moving through space in the direction toward the constellation of Hercules. Later observations and computations have confirmed Herschel’s conclusions, and we have even been able of late to fix with some precision the velocity of this motion, which amounts to 20 kilometers per second. This velocity is a fifteen-thousandth part of the velocity of light. In the one hundred and fifty years elapsed since Bradley determined for the first time the position of numerous stars with modern precision, the solar system must thus have covered a distance of exactly a hundredth part of a ight year—i. e., we are thus enabled to make pictures of the sky as seen from points of view at a mutual distance of a hundredth of a light year. Our eye distance of sixteen light minutes is thus increased more than three hundred fold. True, this distance falls still considerably short of that adopted by Heath, but it appears that, for a considerable part of the stars, it is, though not nearly so great as might be desired, still in a certain way sufficient. IMPOSSIBILITY OF DETERMINING DISTANCE OF INDIVIDUAL STARS. There is, however, a difficulty in the way, which prevents our pic- tures from giving a stereoscopic view of the stars at all, and thus prevents the determination of the distance of any star in this manner. The difficulty is that the changed directions in which, after the lapse of one hundred and fifty years, we see the stars, is not exclusively the consequence of the sun’s motion through space, but is due also to a real motion of the stars themselves. The two causes of displacement which, in the case that we take the diameter of the earth’s orbit as eye-distance, are separable by means of a simple device, become inseparable in the present case. Tn order to see whether this difficulty be or be not absolutely in- superable, I will take a parallel case on the earth. DISTANCE OF INSECT CLOUD. Ata certain distance we observe a cloud of insects hovering over a small pond. In order to evaluate the distance separating the insects from our eye, suppose that we make a photograph; then, after a few seconds, a second one from a slightly different standpoint. It must be evident that even if we have used an instrument which clearly shows the individual insects, the two pictures put in the stereoscope will not furnish a stereoscopic view of them individually; on the contrary, the picture as seen in the stereoscope will be perfectly chaotic. The reason, of course, is that in the interval between the taking of the two photographs the insects have moved. Does it follow that an evalu- ation of the distance can be obtained ? STRUCTURE OF THE UNIVERSE—KAPTEYN. 307 The answer must be, of any individual insect, no; but of the cloud as a whole we can, provided that the cloud as a whole has not moved; or expressed more mathematically: Provided that the center of gravity of the cloud has not moved, we can derive the average dis- tance * of all the insects. We shall be sure of the immobility of the center of gravity if we know that the direction of the motions of the insects is quite at random; but this is by no means required. The motion may be preferentially in a horizontal plane or along a de- termined line, say along the longer axis of the pond, provided only that the motions in any two opposite directions are equally frequent. Not only that, even if the cloud, as a whole, is not immovable, we are not necessarily helpless. For, if the insect cloud andthe photog- rapher were both on a sailing vessel, circumstances would be the same as on the mainland, though now the cloud is in motion. Only, instead of the absolute displacement of the photographic apparatus, we must know the displacement relative to the ship, or rather relative to the insect cloud. This, then, finally is the real thing wanted. We may obtain the distance of the insect cloud, or what comes to the same, the average distance of its members, as soon as we are able to find out the displacement of our point of view with regard to the center of gravity of the cloud. Our case is much the same in the world of the stars. We shall be able to determine the average distance of the members of any arbitrary group of stars, provided that we can find the motion of the solar system, both in amount and in direction, relative to the center of gravity of the group. Now, astronomical observations such as those which led the elder Herschel to his discovery of the solar motion through space enable us to determine the direction of the sun’s motion relative to such groups as the stars of the third, fourth, etc., magnitude. Spectroscopy en- ables us to determine the amount of that motion. We must be able, therefore, to find out the average distance of the stars.in these groups. For other groups, such as the stars having an apparent centennial motion of 10’’, 20’’, etc., there is a. difficulty. Still, however, we have succeeded in overcoming this difficulty by a somewhat indirect process, and pressing into service the stars of which the individual distances are known. This, then, is the upshot of astronomical work on the distances. *The expression “average distance” ought, strictly speaking, to be replaced by the distance corresponding to the average parallax. For sake of clearness I have ventured here and in what follows to substitute one expression for the other. 308 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. WHAT WE KNOW ABOUT STAR DISTANCE. By direct measurement we know the distance of some hundred individual stars. For the rest we know the average distance of any fairly numerous group of stars of determinate apparent magnitude and apparent motion.? The question is: Can this imperfect knowledge of the distances be considered as in any wise sufficient for obtaining an insight into the real arrangement of the stars in space ? I think it can, and I will now try to show in what manner. @ LOCALIZATION OF THE STARS IN SPACE BY A SORTING PROCESS. The method may be best explained as a sorting process. The proc- ess was not actually followed; it would have been too laborious and would have met with some difficulty.’ But the difference is imma- terial, and the present description has, I think, the advantage in point of clearness. Let each of the stars of the second, third, etc., to the eighth mag- nitudes be represented by a little card on which are inscribed the apparent magnitude and the apparent proper motion of the star. Then imagine three sets of boxes. CLASSIFICATION ACCORDING TO MAGNITUDE. First set. Apparent magnitude boxes represented in figure 1. In the box for the second apparent magnitude, as many cards are put as there are stars of the second magnitude in the sky. The total numbers of stars for each magnitude are inscribed on the hd. We thus see that there are in the whole of the sky 46 stars of the second magnitude, 134 of the third, and so on. ®At the present moment some objection might certainly still be made against the generality of this statement. In fact, the scarcity of spectroscopic data is the eause that, though the determination of the solar motion separately for such groups as the stars of determinate magnitude and proper motion is quite pos- sible, it has not yet been carried through. AS a consequence the results used in what follows still rest on the assumption that the centers of gravity of all the groups considered are at rest relative to each other. That this assumption must be probably true, follows from the near identity of the direction of the sun’s motions, furnished by the several groups. 6 For many of the stars used the proper motion is still not known. What is known, however, is the percentage of the stars of each magnitude having a determined proper motion. This knowledge enables us to put in every box the required number of cards showing a determined proper motion, and this is all that is wanted in what follows. STRUCTURE OF THE UNIVERSE—KAPTEYN. 309 1476 4842 15042 Fic. 1.—Apparent Magnitude Boxes. ACCORDING TO MAGNITUDE AND PROPER MOTION. Second sets. Magnitude-motion boxes (fig. 2). The stars in each of the former series of boxes are redistributed over a series of boxes, each of them containing stars of a determined apparent motion. By way of an example, figure 2 shows this new classification for the stars of the fifth apparent magnitude. There is, of course, another such series for each one of the apparent magni- tudes. Those for the fifth have been distributed over 28 new boxes. In the first have been collected the cards representing the stars with a proper motion of 0’’ to 1” per century. The average motion is 0.5, and this has been inscribed on the lid. The little arrow indicates that this number represents a motion. The number 5 surrounded by a star refers to the fact that we have exclusively to do with stars of the fifth apparent magnitude. The second box contains the stars with proper motion between 1’’ and 2” per century, ete. For the larger motions the limits have been taken somewhat wider. In the eleventh box the motions 10’ to 15’” are contained; in the thirteenth, those between 20’ and 30’’; and so on. The number of star cards in each box has been inscribed on the lower right-hand corner of the lid. The figure thus shows, for instance, that there are in the sky 90 stars of the fifth magnitude, having a proper motion between 0’ and 1’’ per century. We have thus arranged the stars according to both the rough criteria of distance at our disposal. For we know perfectly well that in a very general way the fainter the stars and the smaller their apparent motion the farther they must be away. For each of the groups thus obtained we are now able, according to what has been said before, to derive the mean distance. This deter- mination being made, we obtain the mean distances expressed in light years which have been inscribed on the lid with the letter MD prefixed. ia Lt) ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Already we may see now how incorrect it is to imagine all the stars of the fifth magnitude to be placed at one and the same distance as Struve placed them. According to the numbers in our figure, the distance varies from 1670 light years for the stars of the first box, to 11 light years for those of the last. It is true that just the data for these extreme boxes are the most uncertain; still, it 1s evident that even in these mean distances there must be an enormous range. But to proceed, the 86 stars in our sixth box (fig. 2) are at an average distance of 248 light years. Are we compelled to stop here and to assume that the real distance of all the individual 86 stars is aes cn Fic. 2.—Magnitude-motion Boxes. 248 light years? If it were so we would surely still have gained a considerable advantage over Struve. For, owing to want of other data, he saw himself compelled to treat all the stars of the fifth magnitude, that is, the whole of the 28 groups in our boxes, as if they were all at the mean distance of the whole. But yet there would remain in our solution a defect of the same kind, and it would be impossible to say in how far the results’ definitively to be obtained would be influenced. Happily there is an escape. For our last classification, the classifi- cation in the distance boxes, it is of no particular advantage that every individual star gets in its proper distance box. It will be suf- ficient to know how many stars will finally be found in each distance STRUCTURE OF THE UNIVERSE—KAPTEYN. yi box. If this result is obtained, we shall presently see how easy it becomes to study the problem put at the beginning of this lecture. Our aim will be evidently reached if we can find out how many per cent of the stars in any one box have such and such a distance. Now, in order to determine these percentages, it will be sufficient to investi- gate a sample of our stars. STARS OF MEASURED DISTANCE TAKEN AS A SAMPLE. Happily there is the possibility of taking a sample that will help us out of the difficulty, for, as we know, there are in the sky a hundred stars of which astronomers have succeeded in determining the indi- vidual distance with some accuracy. We take these as our sample. They are distributed over a great many of our boxes. We take them all out, having a care to note for all of them the mean distance of the stars in the box to which they belong. For all the hundred stars we now compare their mean distances to their true distances, and thus find out how many per cent of them have true distances between two and three. four and five tenths, and so on, of the mean distance. Third set: Distance bowes. These percentages are all we want for our last distribution, the dis- tribution over the distances. It is true that our sample is a somewhat undesirably small fraction of the whole; it shows, besides, some other weak points; but it appears, happily, & posteriori, that even rather considerable uncertainties in these percentages have but an unimpor- tant influence on the results. We are thus at last enabled to distribute our star-cards according to the true distances. I made the distri- bution over the spherical shells shown in figure 3. The dimensions of these shells have been so chosen that if a star is removed from one shell to the next farther one, the observer at the center will see the star grow fainter by just one magnitude; that is, it will grow very nearly two and one-half times fainter. The figure is not well fitted for bringing out the details of our results. The shells become too narrow toward the center and the more central ones do not allow of the insertion of sufficiently clear figures. For this reason I constructed figure 4. The numbers valid for the several spherical shells have here been entered in equally broad horizontal rows. The drawing does not, therefore, show the real dimensions, but these as expressed in light years, which may be read off on the right-hand side of the drawing. We thus see that the central sphere extends to a distance of 21 light years; that the second spherical shell extends from 21 to 33 years, and soon. In these rows a last set of boxes is placed. There is a box for each apparent mag- 88292—sm 1908——21 312 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. nitude in each of the rows. The stars of the boxes of figure 2 are thus, of course, all contained in the vertical row of boxes, correspond- ing to apparent magnitude 5 in figure 4, DISTRIBUTION ACCORDING TO DISTANCE ILLUSTRATED BY EXAMPLE. In order to illustrate by an example how the stars of the boxes in our figure 3 are distributed over our different shells, that is over our distance boxes of figure 2, take the seventh box. It contains 77 stars at a mean distance of 220 light years. Our countings on the sample showed that about one-fifth of the stars have true distances which are Fic. 3.—Distance Boxes. between 37 and 59 per cent of their mean distance (derived from their apparent magnitude and proper motion). Therefore about one-fifth of our 77 stars must have true distances between 37 and 59 per cent of 220 light years; that is, between 82 and 130 light years; or, finally, 15 stars of our box must find their place in the fifth shell of figure 4; that is, in the box corresponding to the fifth apparent magnitude in that shell. In precisely the same way I find that 21 of them must be placed in the sixth shell, 18 in the seventh, 10 in the eighth, and so on. If, after that, we repeat the process for all the remaining boxes of figure 2, we get, for the fifth apparent magnitude, the numbers in- seribed on the lower side of the boxes corresponding to that magni- tude in figure 4. STRUCTURE OF THE UNIVERSE—KAPTEYN. aillo Further than for the eleventh shell no numbers have been entered. They become too uncertain. As, however, we know the total number of stars of each apparent magnitude, we know the aggregate number which remains to be distributed over the whole of the farther shells. What has here been explained for the stars of the fifth magnitude, has been also done for the other magnitudes between the second and the eighth. The whole of the results are shown in our figure 4. Fic. 4.—Distance Boxes, reconstructed diagram. STARS OF EQUAL LUMINOSITY BROUGHT TOGETHER. _ The main result of the investigation is embodied in these numbers— and first, in every box stars have now been brought together of equal absolute magnitude—that is, of equal luminosity. [For as the stars in each box are at the same distance, and as, at the same time, they are of equal apparent brightness, they must, of necessity, be of equal total light-power; that is, according to our definition, of equal lumin- osity, or absolute magnitude. For the absolute magnitude of a star, I have taken the magnitude the star would show if placed at a dis- ol4 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. tance of 326 light years. The choice of just this number is simply a matter of convenience, and need not be explained here. As a consequence, the stars at a distance of 326 years, which to us appear as stars of the fifth magnitude, will have also the absolute magnitude 5. Those of the same apparent magnitude, but at a dis- tance of 517 light years—that is, just one shell farther—must have the absolute magnitude 4 in order to show us the same brightness, notwithstanding the greater distance. Now, our eighth shell lies just between these limits of distance. In the middle of this shell, there- fore, the stars of apparent magnitude 5 must have absolute magni- tude 4.5. In the box, therefore, belonging to the fifth apparent mag- nitude, eighth shell, all the stars are of absolute magnitude 4.5. In the ninth shell a star must already have the absolute magnitude 3.5 in order to shine as a fifth apparent magnitude at this greater distance, and so on. In this way the absolute magnitudes were found which in our figure have been inscribed on the lids of the boxes. MIXTURE LAW. We are now able to derive at once the mixture law—1i. e., the pro- portions in which stars of different absolute magnitude are mixed in the universe. For in one and the same shell (eleventh) we find two stars of absolute magnitude —1.5, as against three of magnitude —0.5, fifteen of absolute magnitude 0.5, seventy-six of absolute magnitude 1.5, ete. That is, our results for the eleventh shell furnish us with the pro- portion in which stars of absolute magnitude —1.5, —0.5, etc., to 4.5, are mixed in space. The tenth shell gives the proportions for all the absolute magnitudes between —0.5 and 5.5, and so for the rest. All the shells together give the proportions for the absolute magnitudes —1.5 to 14.5, that is for a range of not less than sixteen magnitudes. Not only that, but most of the proportions are determined inde- pendently by the data of quite a number of shells. So, for instance, the proportion of the stars of absolute magnitude 4.5 to those of absolute magnitude 5.5. Each of the shells from the fifth to the tenth furnishes a determination of this proportion. All of them are not equally reliable. If we take this into account, we find that the agree- ment of the several determinations is fairly satisfactory. By a care- ful combination of all the results, a table representing the law of the. mixture of the stars of different absolute magnitude was finally obtained. Rather than show you the direct result, however, I will first replace the absolute magnitudes by luminosities expressed in the total ight of our sun asa unit. This will have the advantage of presenting a more vivid image of the real meaning of our numbers. By photometric measures it was found that the sun, placed at a distance of 326 light years, would shine as a star of magnitude 10.5. STRUCTURE OF THE UNIVERSE—KAPTEYN. 315 In other words, the sun’s absolute magnitude is 10.5. ee mi: DapereAiNO: # ea 18: ae ia ieee eee Ca) coli pte At Aue el ie hs 4) ee iit 3 m4 ce, Stee ne tou ug , A ee ess ; Vie pep i Peel sig) i ' se — r . / moar gt: ; ie ie pe a taste ng aT aN r ra) nay ei ng ; ial : ae oe ma rh ; cis a ie he iene a es. a4 th Me Viera Pee ree) ee, at > nae oe rahi Weicgal MA WANS Sis} gee Ty i an ei) eee ae ee ree tole Ostet ed nit al Le ame x Me oe ress ih a; .T Whos: oie ni . ae rit eats ‘et nian nee ee ; fate ae et aaa a ee Aig y aa 7 a : is : i Hie my ead i ba | ne ae i a hia mye se op -— ag ‘aes aa ot Teh wis ie ee Dethe a te zi a, or = LF T bat) hue ce i et ia ag er u en eae iy He ete i erey: 7 + 4 ae a : he na 1, ; i Sui a ‘i ‘Sig ia ag: ines ane Fyn) ; - ‘i Ree 1%. Ni El Pe a a itn Caney Mant sda ‘Wh cf igs co. oh " Pies te Perrine i rae ae ne hal Y: os leant avi Pia bree oe ee ane ge a Cs ane vo ip Nise , mia y nt : ee an we a oar: fel ae P ar ihe 7 = on Ae i ree | ; "- ; / i Lees Ae se ‘ me © . aan 7 cs e He e | - . =o : t J / ee : be a r Pin _ : i e iy ah D ned re : ‘ ‘ \- a 1 ; ay ma mii, eae Ms nee. peel ah ke An it eee ae ng 7 1h: oe Oe i ‘ at ae a at i “es i : : ; ee a F r , 7 Wl : ve ; Ss y ni a aaa, ri a i ; “/ ; meet ’ ees ahs, ay if Ve To Pe te ih thy ai vb ae) ; 3 rey ie : h ‘ th "iy rae : sak Pare en: | ie hr, wc i ay eta oe : pete . = = : : ay ; dee) men i Mi 7 y wien 7 | 5 cy ; r ats La ett, i : basi? uw & | ‘ . one ay , lle ee ae ay, nk Bigheoatt ae " genre tal? 4} Tih ae -y Pe vaya sat nl i cry a2 ee ce Seine ue way aun’, oes . » ee Jes eed ms ale io v7 r vey om ty : = tie | an ae ao i ene rae tg my panda . ie = fo a a soe a Saws SOLAR VORTICES AND MAGNETISM IN SUN SPOTS. [With 5 plates. | By C. G. ABBOT. Director, Smithsonian Astrophysical Observatory. At the present time the growth of knowledge of the sun is mainly through the applications of the spectroscope, although in the past information of great value was obtained by purely telescopic obser- vations. Thereby the rotation of the sun was first measured, and the remarkable retardation of the rotation with increasing distance from the solar equator was established. Furthermore, it was discovered that the prevalence of sun spots waxes and wanes in periods which average about eleven years, although individual sun-spot cycles range from eight to fourteen years in length. By utilizing with the ereatest art the rare instants of good seeing, Langley made his cele- brated and beautiful drawings of the detailed structure within and around a typical sun spot. Similarly, by the selection of specially favorable conditions, Janssen was able to obtain photographs which show, as well as may be, the granular appearance of the general sur- face of the sun. Owing to the fortunate circumstance that the moon . sometimes covers-the body of the sun, leaving the surroundings open to view undimmed by the glare of the skylight, the beautiful struc- ture of the corona and prominences became known from eclipse observations. Comparative studies of successive eclipses prove these features to be variable in high degree. The changes seen in the sun spots, prominences, and corona made it clear that very great rear- rangements of the material of the sun go on continually; but if it were not for the aid of the spectroscope, knowledge of the character of these changes would probably forever be very meager. Looking toward the sun we see through a layer of solar material, which, if we neglect the corona, may be several thousand miles deep. In this layer are contained the vapors of many of the elements found on the earth, notably of sodium, calcium, magnesium, iron, titanium, vanadium, chromium, and others, besides several of the permanent gases, like hydrogen and helium. Owing probably to the differing densities of these elements, and in a rough way connecting itself with their atomic weights, their distribution in level is not a homogeneous 321 322 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. mixture, but the heavier elements sink toward lower levels in general. Such partial separations in level and the vigorous motions which take place in the sun are effectually hidden to the telescopic observer, partly because he can not tell one transparent gas from another and partly owing to the circumstance that the motions at different levels are mixed beyond recognition on account of the great depth of the field of view. The separate currents are as undistinguishable as the separate motions of the motes of a wide sunbeam when viewed from a distance. All this is changed for the spectroscope. Iron vapor strongly ab- sorbs the rays of certain special wave lengths, and vapors of the other elements—hydrogen, calcium, etc.—do the like for still other rays. Hence instead of the brilliance due to the extremely hot interior lay- ers of the sun there is found in the Fraunhofer lines chiefly the less intense emission of the cooler vapors of the elements which lie in the outer surface layers. If the sun is viewed in the red spectral line C (now usually called Ha), there is seen chiefiy the hydrogen and not the iron, sodium, or other elements. Hydrogen has several other strong lines in the solar spectrum. Among the most conspicuous are H (also called F) in the blue, Hy and H6& in the violet. It is well known that when light is produced by heating a bar of iron or other substance to incandescence the light is at first red, and becomes white and, finally, in the electric arc, even of a violet tinge with increasing temperature. In short, the violet end of the spectrum requires a higher temperature for its copious emission than does the red. This holds in a general way for gases in their emission of line spectra as well as for solids with their continuous spectrum. Accord- ingly the red Ha line will be stronger with respect to the violet H8 line when emitted from hydrogen gas at a lower temperature than at a higher one. Hence we may expect that if a mass of hydrogen gas extends for a very considerable thickness in the outer layers of the sun the spectrum of the higher and therefore cooler parts will be relatively stronger at Ha than at Hs. Therefore if the sun is viewed only by Ha light, the aspect will be more that of the highest levels than of the lower ones. If viewed on the other hand through H68, or still more if one of the lines of iron is chosen, it will be on the whole more of the aspect of a lower section which is presented. Readers will recall that the Smithsonian Report for 1904 con- tained an abstract of the account, by Hale and Ellerman, of the Rumford spectroheliograph of the Yerkes Observatory. Referring for details of the instrument to that publication, it is enough to say here that the spectroheliograph, invented by Hale about 1890, is to all intents and purposes a screen which limits the observer to rays of a single shade of color, and this may be at any part of the spec- trum. By the aid of the spectroheliograph the sun may be photo- SOLAR VORTICES AND MAGNETISM IN SUN SPOTS—ABBOT. 323 graphed in hydrogen, calcium, or iron light, and in the case of hydro- gen, which has lines in several parts of the spectrum, the light may be either violet, blue, or red. Spectroheliographic pictures show many details not seen in telescopic views of the sun. Mr. Hale has named the elementary patches which go to make up this newly found detail “ flocculi.” Recently very striking and interesting photo- -graphs of solar structure have been made by the spectroheliograph at the Mount Wilson Solar Observatory under Mr. Hale’s direction, and the following abstract of an account of some of them is taken from his paper entitled “ Solar Vortices: ” ¢ SOLAR VORTICES. The problem of interpreting the complex solar phenomena recorded by the spectroheliograph has occupied my attention since the first work with this instrument in 1892. The measurement of the daily motions in longitude of the calcium flocculi has led to several new determinations of the solar rotation,? and their areas, measured by a photometric method, are being used as an index to the solar activity. Various investigations on their forms at different levels, their distribution in latitude and longitude, etec., have also been carried out. But the failure of the calcium flocculi to indicate the existence of definite currents in the solar atmosphere has been a disappointment. The hydrogen flocculi, though occupying the same general regions on the sun’s disk, are distinguished from those of calcium by several striking peculiarities. In the first place, most of them are dark, while the corresponding calcium (H:) flocculi are bright. Secondly, as I have recently shown,’ they seem to obey a different law of rotation, in which the equatorial acceleration (better, the polar retardation), shared by the spots, facule, and calcium flocculi, does not appear. A third peculiarity, briefly mentioned in previous papers, is clearly visible on many hydrogen photographs. It is a decided definiteness of structure, indicated by radial or curving lines, or by some such distribution of the minor flocculi as iron filings present in a magnetic field (see, for example, Astrophysical Journal, Vol. XIX, Pls. X and XII). First recognized at the beginning of our work with the hydrogen lines in 1903, this suggestive structure has re- peatedly shown itself on the Mount Wilson negatives. But its true meaning did not appear until the results described in this paper had been obtained. With the Rumford spectroheliograph the hydrogen lines Hf, Hy, and H6 were used. Certain differences between the photographs, which seemed to depend upon the wave length, pointed to the desirability of trying Ha, but plates sufficiently sensitive to red light were not to be had at that time, and therefore the experiment was postponed. The extreme sensitiveness in the red of plates prepared according to a formula due to Wallace ° now renders it a simple matter to photograph the sun with Ha. * Astrophysical Journal, Vol. XXVIII (September), 1908. [The plate num- bers do not correspond with those in original paper—Eprror. | + Hale and Fox, The Rotation of the Sun, as Determined from the Motions of the Calcium Flocculi. Carnegie Institution (in press); Fox, Science, April 19, 1907 ; Hale, Contributions from the Mount Wilson Solar Observatory, No. 25; Astrophysical Journal, Vol. XXVIT, p. 219, 1908. © Hale and Ellerman, Publications of the Yerkes Observatory, Vol. III, pt. I. 4Hale, Contributions from the Mount Wilson Solar Observatory, No. 25; Astrophysical Journal, Vol. XXVII, p. 219, 1908. ¢ Astrophysical Journal, Vol, XXVI, p. 299, 1907. 324 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Some preliminary work with the spectroheliograph attachment of the 20-foot Littrow spectograph of the tower telescope, in which I had the assistance of Mr. Adams, indicated that bright flocculi are more numerous and extensive when photographed with Ha than when Ho is used. I then tried Ha with the 5-foot spectroheliograph of the Snow telescope, and immediately obtained excellent results. The images were stronger and of much better contrast than those given by Hé6. Moreover, the curved and radial structure surrounding sun spots was so striking as to lead to the hope that important advances might be expected to follow from the systematic use of the Ha line. * * * This is so definite in form and so unmistakable in character as to satisfy the hopes aroused by the earlier photographs. It seems evident, on mere inspection of these photographs, that sun spots are centers of attraction, draw- ing toward them the hydrogen of the solar atmosphere. Moreover, the clearly defined whirls point to the existence of cyclonic storms or vortices. * * * In the present paper I wish to illustrate the phenomena photographed with the aid of Ha in the neighborhood of a spot which reached the east limb of the sun at 8°16" a.m, on May 26, 1908. A photograph of this spot, made by myself with Ha on May 29, at 4” 26™ p. m. Pacific standard time, is reproduced in figure 1, plate 1. The whirl structure, which is clearly shown by this photograph, is also very distinct, though of somewhat different form, on the photograph of May 28. It is interesting to inquire as to the probable level of the region in which this whirl occurred, and the height of the long dark flocculus south of the spot. For this purpose we may examine photographs of the chromosphere and prominences at the limb, taken on May 25, 26, and 27. In the first of these, made on May 25 at 9" 18™ a. m. (No. 4142), a long narrow prominence, extending toward the north, rises from the limb at position angle 92°, a point about one degree north of the spot. It makes an angle of about 12° with the limb, and fades out at the upper end, its length being approximately 90’’° (geocen- tric). There are other small filamentary prominences in the region extending about 7° north of the spot, and smaller elevations in the chromosphere to the south. At position angle 98° a bright prominence rises to a height of about 20’’ and then slopes to the chromospheric level at position angle 107°. Near its southern end is an independent filamentary prominence about 55’’ high. On May 26, at 6" 38™ a. m. (No. 4144), the prominences were photographed at the east limb. The lowest point in the chromosphere on this photograph corre- sponds to the position (position angle 93°) where the spot crossed the limb about two hours later. It will be seen that these prominences, which extend from posi- tion angle 82° to 106°, cover much of the region in which the whirl structure of plate 1 appears. The prominence south of the spot is very bright and its highest point reaches an elevation of about 35’’,. On May 27, at 5" 22™ p. m. (No. 4152), a prominence about 25’’ high extends from position angle 105° to 109°. This is doubtless the eastern extremity of the strong flocculus in plate 1, ' which may be there seen curving toward the spot. We may now pass in rapid survey the more important photographs of the disk. On May 28, at 6" 58™ a. m, (No. 4157), the spot is near the east limb and the whirls are well shown. ‘To the east of the spot is a long, narrow line of bright hydrogen. On May 29, at 6" 24" a. m. (No. 4171), the whirls are very dis- tinct and differ in many respects from those shown on May 28. Hruptive regions of bright hydrogen are seen southeast and west of the spot. The eastern end of the long, dark flocculus is changing in form, and bridges are appearing over the spot. Negative No. 4175, taken one hour and nineteen minutes later, seems to show distinct changes in the whirls, though they are not measur- able. On May 29, at 4° 26™ p. m. (No. 4176), the whirls resemble those shown in negative No. 4175, but exhibit some marked changes, An eruption which Smithsonian Report, 1908.—Abbot. PLATE 1. Fic. 1.—SUN-SPOT AND HYDROGEN (Ha) FLOCCULI. 1908, May 29, 45 26m p.m. Scale: Sun’s diameter=0.3 meter. Fic. 2.—SUN-SPOT AND HYDROGEN (He) FLOCCULI. 1908, June 2, 64510™a.m. Scale: Sun’s diameter=0.3 meter. Smithsonian Report, 1908.—Abbot. = PLATE 2. Fic. 1.—SUN-SPOT AND HYDROGEN (Ha) FLOCCULI. 1908, June 3, 5h 22™ p.m. Seale: Sun’s diameter=0.3 meter, Fig. 2.—SUN-SPOT AND HYDROGEN (//a) FLOCCULI. 1908, June 4, 62 12™a,m. Seale: Sun’s diameter=0.3 meter. SOLAR VORTICES AND MAGNETISM IN SUN SPOTS—ABBOT. 325 appears on the former plate southeast of the spot continues, but is changed in form and less brilliant than before. A strong eruption of peculiar form appears southwest of the spot, and bright hydrogen to the northeast. Strong, dark flocculi have also developed at many points around the spot. The eastern end of the long, dark flocculus is still changing, and a projection appears west of its center (see plate 1). A negative taken on the same day at 5" 13™ p. m. No. 4178) shows further changes in both bright and dark structure, especially in the region southwest of the spot. A fork has developed in the western end of the long dark flocculus, and a small but very dark flocculus appears just west of the spot. Another photograph (No. 4179), the first exposure of which was made at 5" 26™ p. m., shows a bright eruption west of the spot, where the small dark flocculus appears on No. 4178. The eruption underwent considerable change of form while the five exposures on this plate, separated by intervals of a few minutes, were being made. At 6" 04™ p. m. negative No. 4181 shows that the eruption had subsided, and brings out other definite changes in structure near the spot. The small dark flocculus has disappeared. On May 31, at 8" 09™ a.m. (No. 4188), the fork at the western extremity of the long dark flocculus has partially closed. No eruptions appear west of the spot, but there are bright ones to the southeast. Other important changes are evident, and the two bridges across the spot are conspicuous. On June 1, at 6° 30™ a. m. (No. 4189), the fork at the western end of the long dark flocculus appears more nearly as it did in negative No. 4181, and the two bridges over the spot are very marked. A negative taken fifteen minutes later (No. 4190) shows distinct changes, especially in the region south and southeast of the spot, At 5" OS™ p.m. of the same day negative 4193 shows a more distinct whirl near the spot, and the long dark flocculus appears to be growing shorter at its eastern end. On June 2, at 6" 10" a. m. (No. 4196), the whirling structure is very marked and more nearly symmetrical about the spot, which is divided into two parts (fig. 2, pl. 1). At 7° 27" a. m. (No. 4198) the whirl is also very marked and somewhat changed in form. Up to this time the changes, while in many cases rapid, were not especially violent. On June 3, in an interval of about ten minutes, a remarkable trans- formation occurred. The long dark flocculus, which had been gradually chang- ing in form and position, was suddenly drawn into the spot. As figure 2, plate 1, illustrates, the whirls were very conspicuous on the preceding day. Unless separated by centrifugal force, as suggested by Professor Nichols. ¢ Walter M. Mitchell, *‘ Reversals in the spectra of sun spots,” Astrophysical Journal, Vol. XIX, p. 357, 1904; ‘* Researches in the sun-spot spectrum, region F toa,” ibid., Vol. XXII, p. 4, 1905; ‘*‘ Results of solar observations at Princeton, 1905-1906,” ibid., Vol, XXIV, p. 78, 1906, . SOLAR VORTICES AND MAGNETISM IN SUN SPOTS—ABBOT. 329 Investigations on the spectra of iron, manganese, chromium, titanium, vana- dium, and other metals conspicuous in spots, made with the are, spark, and flame, indicated that the change of the relative intensity of lines observed in passing from the solar spectrum to the spot spectrum is due to a reduction of the temperature of the spot vapors. Subsequent work with a new electric ‘furnace by Doctor King,? the details of which have not yet been published, seems to leave little doubt that this explanation is correct. It is supported by the presence in the spot of compounds which appear to be dissociated at the higher temperature outside the spot, and by the resemblance of spot spectra to the spectra of red stars.¢ ; While our investigations have thus furnished a plausible explanation of some of the characteristic phenomena of sun-spot spectra, the widening of lines and the presence of doublets are among the remaining peculiarities that demand consideration. AS we have seen, however, these very peculiarities are precisely what would be expected if a magnetic field were present. Prompted by the theoretical considerations outlined above, and encouraged by their apparent agreement with the facts of observation, I decided to test the components of the spot doublets for evidences of circular polarization and to seek for other indications of the Zeeman effect. METHOD OF OBSERVATION. ‘The tower telescope forms an image of the sun, about 6.7 inches (17 centi- meters) in diameter, on the slit of a vertical spectrograph of 30 feet focal length. This instrument, to which reference has already been made, stands in a well with concrete walls, the grating being about 263 feet (S meters) below the surface of the ground. The temperature at the bottom of the well is so con- stant that exposures of any desired length may be given, without danger of a shift of the lines resulting from expansion or contraction of the grating. A Fresnel rhomb and Nicol prism? are mounted above the slit, so that the light of the solar image passes through them. If the doublets in spots are produced by a magnetic field, the light of their components, circularly polarized in opposite directions, should be transformed by the rhomb into two plane polar- ized rays, differing 90° in phase. Thus, in a certain position of the Nicol, the “Hale, Adams, and Gale, ‘“ Preliminary paper on the cause of the character- istic phenomena of sun-spot spectra,’ Contributions from the Mount Wilson Solar Observatory, No. 11; Astrophysical Journal, Vol. XXIV, p. 185, 1906; Hale and Adams, “ Second paper on the cause of the characteristic phenomena of sun-spot spectra,” Contributions from the Mount Wilson Solar Observatory, No. 15; Astrophysical Journal, Vol. XXV, p. 75, 1907. » King, “An electric furnace for spectroscopic investigations, with results for the spectra of titanium and vanadium,” Contributions from the Mount Wilson Solar Observatory, No. 28; Astrophysical Journal, Vol. XXVIII, p. 300, 1908. © Hale and Adams, ** Sun-spot lines in the spectra of red stars,’ Contributions from the Mount Wilson Solar Observatory, No. 8; Astrophysical Journal, Vol. XXIII, p. 400, 1906; Adams, “ Sun-spot lines in the spectrum of Arcturus,” Contributions from the Mount Wilson Solar Observatory, No. 12; Astrophysical Journal, Vol. XXIV, p. 69, 1906. 4 Obtained for this purpose in 1905, when the idea of searching for the Zee- man effect in sun spots had already occurred to me. A visual test of the spot lines for plane polarization, made with the 18-foot spectrograph in 1906, before we had photographed the doublets, gave negative results. 330 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. light from the red component should be transmitted and that of the violet com- ponent cut off. When rotated 90° in azimuth, the Nicol should transmit the violet component and cut off the red component. Complete extinction of either component is hardly to be expected, because the light from the spot does not, in general, come exactly along the lines of force, and the doublets may therefore exhibit some traces of elliptical polarization. Moreover, the beam of sunlight undergoes two reflections on the silvered surfaces of the coelostat and second mirrors of the tower telescope, where elliptical polarization must again be in- troduced.“ By setting the rhomb at the proper angle, the latter effect, which is not very large, can be almost wholly eliminated, but the former may play some part, even when the spot is at the center of the sun. The light of the spot, after transmission through the rhomb and Nicol: comes to a focus in the plane of the slit. While photographing the spot spectrum the slit is covered except at its central part, where a portion corresponding in length (from 1 to 2 millimeters) to the diameter of the umbra, receives the light. During the exposure, which may continue from a few minutes to over an hour, the image of the umbra is kept as nearly as possible central on the slit, any irregularities in the motion of the driving clock being corrected by the observer. As the exposure for the spot spectrum is from five to twenty times as long as for the solar spectrum, it is evident that care must be taken to prevent light from regions outside the spot from entering the slit. For a comparison spectrum sunlight is used, generally from a point in the solar image a short distance away from the spot, where none of the character- istic spot phenomena appear. During the exposure, that part of the slit which previously received the light of the umbra is covered, and sunlight admitted on either side. The light of the comparison spectrum passes through the rhomb and Nicol, both of which occupy the same positions as in the case of the spot. Care is taken to see that the grating is fully illuminated, both for the spot and comparison spectra, in all positions of the Nicol. CIRCULAR POLARIZATION ALONG THE LINES OF FORCE. My first observations were made on June 24, in the second order of the grating, but the results were not conclusive. On June 25 I obtained some good photographs in the third order, of the region »’ 6000-6200, using Seed’s process plates, sensitized for the red by Wallace’s three-dye formula.2 These clearly showed a reversal of the relative intensities of the components of spot doublets when the Nicol was turned through an angle of 90°. Moreover, many of the widened lines were shifted in position by rotation of the Nicol, indicating that light from the edges of these lines is circularly polarized in opposite directions. The displacements of the widened lines appeared to be precisely similar in character to those detected by Zeeman in his first observations of radiation in a magnetic field. A series of photographs, made with the Nicol set at various angles, soon showed the two positions giving the maximum effect. At these positions the weaker components of the strongest doublets are not always completely cut off, but their intensities are greatly reduced. Sometimes hardly a trace of the weaker component remains, as may be seen in the case of the vanadium doublet at X\ 5940.87 (pl. 4). In this plate No. 5 shows the doublet in the ordinary spot spectrum, photographed without the rhomb and Nicol. No. 4, @A study of the elliptical polarization of these mirrors has been made by Doctor St. John. + Astrophysical Journal, Vol. XXVI, p. 299, 1907, PLATE 4. “M 066 [O0IN LSOP6S SUV T ‘o[Rog “STOTq \ =. ‘S}OTQuOp Jo slusuUod UI0D JO] ‘sJOTQUOP JO syuoMOdUIOD Yo[OTA SUIMOYS ‘YOds UtoeyJoU JO viquIn oUuG (Zz) “HE o19 ‘[OOIN *Sq9] VIN ‘SJOTGHOp JO syueucduT0D pol sUIMOYS “yods ULOYINO (T) She. lables le, Wiha See Saat i, aba ily 28 LLS16G (1) Smithsonian Report, 1908.—Abbot. PLATE 5 SUN-SPOTS AND HYDROGEN FLOCCULI, SHOWING RIGHT AND LEFT HANDED VORTICES. 1908, September 9, 64 20m a, m. Scale: Sun’s diameter=0.3 meter. SOLAR VORTICES AND MAGNETISM IN SUN SPOTS—ABBOT. 331 from a photograph (T 190) made with the Nicol set at 61° E., shows only the red component of the doublet. No. 3 illustrates the effect of turning the Nicol 90°; only the violet component remains. Other spot lines in these photographs change in a similar way. Photographs like these seemed to leave no doubt that the components of the spot doublets are circularly polarized in opposite directions. Since the only known means of transforming a single line into such a doublet is a strong mag- netic field, it appeared probable that a sun spot contains such a field, and that the widening and doubling of the lines in the spot spectrum result from this cause. But much remained to be done before the proof could be regarded as complete. . Since this preliminary work I have made over 200 photographs of spot spectra with polarizing apparatus before the slit. In addition to this col- lection of plates, numerous photographs of spot spectra, some taken with polarizing apparatus by Doctor St. John, and others made without Nicol or rhomb by Mr. Adams and myself, are available for study. These have been used for the investigation described in the following pages. REVERSED POLARITIES OF RIGHT AND LEFT HANDED VORTICES. If a Nicol is set so as to cut off the violet component of a doublet observed along the lines of force of a magnetic field, reversal of the current will cause the red component to disappear and the violet component to become visible. Reversal of the direction of the current in a magnet corresponds to reversal of the direction of revolution in a solar vortex. If it could be shown, by an independent method, that in two sun-spot vortices the charged particles are revolving in opposite directions, the red components of the doublets should appear in the spectrum of one spot, and the violet components in that of the other, the position of the rhomb and Nicol remaining unchanged. Fortunately the spectroheliograph plates indicate the direction of revolution in the solar vortices. The vortices are constantly changing in appearance, and the stream lines are not always clearly defined. Plate 5 is reproduced from a photograph of the sun made by Mr. EHlWerman with the 5-foot spectro- heliograph on September 9 and 10. It shows two spots, one in the northern, the other in the southern hemisphere, with vortices indicating revolution in opposite directions, if we may judge from the curvature of the stream lines.¢ Portions of the spectra of these spots, photographed by myself on September 9, are reproduced in plate 4. No. 1 shows the spectrum of the southern spot, in which the direction of revolution was clockwise, taken with the Nicol set at 29° W. . Only the red components of the doublets appear. The northern spot, in which the revolution was counter clockwise, was then photographed (2). Although the Nicol and rhomb remained in the same position as before, the red components of the doublets are now cut off, while the violet ones are visible. During this exposure the slit was kept on the western umbra of the northern spot, which was divided into two parts by a bridge (not shown in the repro- ductions). Another exposure, with Nicol and rhomb as before, was then made on the eastern umbra of the same spot (8), with results similar to those ob- tained for the western umbra. For the final exposure (4) the slit was kept on the eastern umbra of the northern spot, and the Nicol rotated 90°. As was to be.expected, the red components were brought into view, and the violet components extinguished. This spectrum is therefore precisely similar to that of the southern spot, which was taken with the Nicol in the reverse position. “Right and left handed vortices have also been found jin the same hemi- sphere. 332 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. This result has been confirmed by other photographs, which indicate that the direction of the displacement always depends upon the direction of revolution in the vortex. PLANE POLARIZATION ACROSS THE LINES OF FORCE. So far we have confined our attention to polarization phenomena observed along the lines of force. But it is well known that the doublets are, in general, transformed into triplets when observed in a magnetic field at right angles to the lines of force. The components of the triplets are plane polarized, the central line in a plane at right angles to the plane of polarization of the side components. It should be possible to detect similar phenomena in spot spectra, if they are produced in a magnetic field. It naturally happens that these spectra are most commonly observed when the spots are not very far removed from the center of the sun, because fore- shortening near the limb reduces the umbra to a narrow strip difficult to keep on the slit. This may partially explain why our photographs of spot spectra, taken without polarization apparatus, show the doublets without a trace of a central component. But it does not account for the failure of the central line to appear in the spectra of spots well removed from the center. It is true that a few triplets occur in all of our spot spectra, such as X5781.97, AGOG4.85, and 6173.55. But these I have regarded as probable examples of an exceptional type of lines, observed in the: laboratory as triplets along the lines of force. * ok * * * Bo *k LABORATORY TESTS. If the widened lines and doublets in spot spectra are produced by a magnetic field, an equal degree of widening and an equal separation of the components of doublets should be found in the laboratory when the same lines are observed in a field of equal strength. As the necessary apparatus was fortunately avail- able, the work was at once undertaken in our Pasadena laboratory by Doctor King. It is conceivable that under conditions analogous to those that give rise to the Hs and Kz; lines, a doublet might be produced within the strong magnetic field of the spot, and a single line, at the center of the doublet, by the absorption of the vapor at a high level, where the field strength is low. 334 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. of measurement. The other doublets, \ 5908.56 and 5988.04, show in the spot spectrum but little more than one-half the separation that would be expected on the assumption that the strength of the field is the sante for all of these lines. On consideration it will be seen, however, that the separation of the doublets must depend, in some degree, on the distribution of the absorbing vapor in the solar atmosphere, and on the coefficient of absorption of the particular line employed. A striking instance of this kind, affecting lines of the same series, is illustrated in the case of hydrogen, described in a previous paper.? Although the H6 line extends to the upper part of the chromosphere and prominences, the mean level represented by its absorption is much lower than that given by Ha. The consequence is that Ha enables us to photograph the solar vortices, the characteristic stream lines of which do not appear at the lower H6 level. Simi- larly, if the intensity of a given titanium line falls off rapidly, the level repre- sented by this line may be comparatively low. If, on the other hand, its intensity curve is of such a form as to indicate that the absorption at higher elevations plays an important part, the mean level represented by the line may be considerably higher than in the previous case. To settle this question we must know: (1) The range of elevation in the spot of the vapors of iron, titanium, and other elements; (2) the intensities of the lines of these elements at different levels; (8) the rate at which the strength of the field decreases upward. In the absence of information regarding the first two points, we may inquire as to the probable relative behavior of titanium, iron, and other elements if the distribution of the vapors at different levels were the same as in the chromo- sphere. From a discussion of a large number of photographs of the flash spec- trum, made by different observers at several eclipses, Jewell has compiled a table showing the heights above the sun’s limb attained by various lines in the blue and violet.2 The heights for titanium range from 100 miles (160 kilo- meters) for \ 4466.0 to 3,500 miles (5,640 kilometers) for \ 4466.7, while certain strong enhanced lines in the ultra-violet reach elevations of 6,000 or 8,000 miles (9,660 or 12,880 kilometers). For iron the minimum height is 200 miles (3820 kilometers) for \ 4482.4 and the maximum 1,000 miles (1,610 kilometers) for 4584.0. Chromium ranges from 100 miles for \ 4280.2 to 1,200 miles (1,930 kilometers) for \ 4275.0; manganese from “100 miles or more” for » 4451.8 to “800 miles (1,290 kilometers) or more” for \ 4030.9; vanadium from 100 miles for \ 4890.1 to 200 miles for \43879.4. It thus appears that the range in level represented by the titanium lines is much greater than for the lines of iron, chromium, manganese, and vanadium. If the vapors were similarly distributed in spots, the maximum strength of field indicated by the titanium lines should therefore correspond with the maximum value for iron, but some titanium lines, produced by absorption at higher mean levels, should give lower field strengths. Chromium should agree more nearly with iron. Vanadium, if the less refrangi- ble lines reach no greater elevations, should give closely accordant (maximum) values for the field strength. It will perhaps be possible, with the aid of the 30-foot spectrograph, to determine the relative levels in the chromosphere attained by most of the lines in question, but it is a much more difficult matter to do this for sun spots. I hope, however, that our new spectroheliograph of 30 feet focal length may throw some light on this subject. It is evident that these considerations will have no bearing on the present problem, unless the field strength decreases very rapidly upward in spots. “Solar Vortices, p. 3. b“ Total Solar Eclipses of May 28, 1900, and May 17, 1901,” Publications of the United States Naval Observatory, second series, Vol. IV, Appendix I. SOLAR VORTICES AND MAGNETISM IN SUN SPOTS—ABBOT. 835 That this probably occurs is shown by the fact that the D lines of sodium and the b lines of magnesium are usually but slightly affected in the spot spectrum,® and are displaced through a very small distance when the Nicol is rotated. Thus, at the level represented by these lines, which attain elevations in the chromosphere probably not exceeding 5,000 miles, the field strength is reduced to a small fraction of its maximum value. The following doublets have been measured in the spectrum of chromium: TABLE III.—Chromium doublets. é 4), spark. : 4), spark. Wave length. Ai, spark. | — 4.9. | 44, spot. é. “AA, spot. BSS OOo set we nweisciaa ce ctlccc cc ccs cute cece 0. 636 0.130 0.188 +0.058 3.4 GOB LO ne 2 cei nen stee nate oaawiaslee casathace vee - 676 - 138 - 085 — .048 8.0 SM SIOO a ese nee cee cinnalee eee eseeescse -610 . 124 - 161 + .037 Bi/ Ue AU tcetare e cterciste e (aieieaisicis erelolaietre ss ereiv erecta ay fat) - 154 121 — .033 6.2 DLOLAD Temectsaaciace stasinisicaiaeceisie soale same emies - 922 - 188 -212 + .024 4.3 GY AS8 978 OS AR COREE SOE BOCES CeCe are «tia 158 137 — .021 5.6 i845 OSs secre eaccee seeicadueaee ne ccsieasisencs 720 - 147 121 — .026 6.0 ON SO LO Spree ae oe Serica sine eho we acetone 707 - 144 137 — .007 Goal In photographing these lines in the spark the strength of the field was 12,500 gausses. The strength of the field in spots, as indicated by ee mean separation of the chromium doublets, is therefore 2,600 gausses. * * SIGN OF THE CHARGE THAT PRODUCES THE FIELD IN SUN SPOTS. If the evidence presented in this paper renders probable the existence of a magnetic field in sun spots, it is of interest to inquire concerning the sign of the charge which, according to our hypothesis, produces the field. * * #* In the case of the solar vortices we have to consider two sets of charged particles, which may be entirely distinct from one another: (1) those whose vibrations give rise to the lines in the spectra of spots, and (2) those that carry the charge which, by the hypothesis, produces the magnetic field. The Zeeman effect supplies the means of determining the direction of the lines of force of the sun-spot fields, and photographs of the vortices, made with the spectrohelio- graph, indicate the direction of revolution of the particles. Thus we are in a position to determine the sign of the charge carried by the particles which pro- duce the fields. As pointed out independently by Kénig and Cornu, the violet component of a magnetic doublet observed along the lines of force is formed by circular vibrations, having the direction of the current flowing through the coils of the magnet.2 From observations of circularly polarized light, made in our Mount Wilson laboratory by Doctor St. John and confirmed by myself, it appears that when the Nicol prism of the tower spectrograph stands at 60° HE. it transmits the violet component of a doublet produced in a magnetic field directed toward the observer. From Biot and Savart’s law the direction of the current causing such a field is counter-clockwise, as seen by the observer. In the same position the Nicol also transmits the violet component of a doublet ee ee ee ee ae ee “Except for the strengthening of the wings, which may be produced by some cause other than a magnetic field. » See Cotton, Le phénoméne de Zeeman, chap. vii, Kénig. Wied. Ann. Vol. 62, p. 240, 1897. 336 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. produced in a sun spot surrounded by a vortex in which the direction of revolu- tion is clockwise. As a negative charge revolving clockwise produces a field of the same polarity as an electric current flowing counter-clockwise, we may conclude that the magnetic field in spots is caused by the motion of negative corpuscles. PROBABLE SOURCE OF THE NEGATIVE CORPUSCLES. We may now consider the probable source of a sufficient number of negative corpuscles to produce a field of about 2,900 gausses in sun spots. In his Conduction of Electricity through Gases (p. 164) J. J. Thomson writes as follows: “We thus are led to the conclusion that from an incandescent metal or glow- ing piece of carbon ‘corpuscles’ are projected, and though we have as yet no exact measurements for carbon, the rate of emission must, by comparison with the known much smaller rate for platinum, amount in the case of a carbon fila- ment at its highest point of incandescence to a current equal to several amperes per square centimeter of surface. This fact may have an important application to some cosmical phenomena, since, according to the generally received opinion, the photosphere of the sun contains large quantities of glowing carbon; this earbon will emit corpuscles unless the sun by the loss of its corpuscles at an earlier stage has acquired such a large charge of positive electricity that the attraction of this is sufficient to prevent the negatively electrified particles from getting right away from the sun; yet even in this case, if the temperature were from any cause to rise above its average value, corpuscles would stream away from the sun into the surrounding space.” On another page (168) Thomson also remarks: ‘‘ The emission of the negative corpuscles from heated substances is not, I think, confined to the solid state, but is a property of the atom in whatever state of physical aggregation it may occur, including the gaseous.” After illustrating this in the case of sodium vapor, Thomson adds (p. 168) : ““The emission of the negatively electrified corpuscles from sodium atoms is conspicuous, as it occurs at an exceptionally low temperature. That this emis- sion occurs in other cases, although at very much higher temperatures, is, I think, shown by the conductivity of very hot gases (or at any rate by that part of it which is not due to ionization occurring at the surface of glowing metals), and especially by the very high velocity possessed by the negative ions in the case of these gases. The emission of negatively electrified corpuscles from atoms at a very high temperature is thus a property of a very large number of elements, possibly of all.” Thus the chromosphere, as well as the photosphere, may be regarded as copious sources of negatively electrified corpuscles.. The part played by these corpuscles in sun spots can not be advantageously discussed until the nature of the vortices is better understood. At present it is enough to recognize that the supply of negative electricity appears amply sufficient to account for the magnetic nelds; * + * EXTERNAL FIELD OF SUN SPOTS. We have already seen that the strength of the field in spots apparently changes very rapidly along a solar radius, and is small at the upper level of the chromo- sphere. “Wor this reason a discussion of the very interesting suggestion of Prof. BE. F. Nichols, that the positively and negatively charged particles are separated by centrifugal action in the spot vortex, is reserved for a subsequent paper. SOLAR VORTICES AND MAGNETISM IN SUN SPOTS—ABBOT. 337 If subsequent work proves this to be the case, it will appear very improbable (as indicated by theory) that terrestrial magnetic storms are caused by the direct effect of the magnetic fields in sun spots. We have some reason to think that their origin may be sought with more hope of success in the eruptions shown on spectroheliograph plates in the regions surrounding spots. * * # Mount WILSON SOLAR OBSERVATORY, October 7, 1908. ADDENDUM. The fact that the doublets in the sun-spot spectrum do not change to triplets, even when the spot is as much as 60° from the center of the sun, appeared, when the proof of the above paper was corrected, to be a serious argument against the magnetic field hypothesis. Thanks to the recent work of Doctor King, this difficulty no longer exists, at least in the case of several iron and titanium lines. Photographs of the spark spectrum in a strong magnetic field, taken at right angles to the lines of force, show that the iron lines \\6213.14, 6301.72, and 6337.05 are doublets, with no trace of a central component. As these lines are also doublets when observed parallel to the lines of force, it is only natural that they should be double in spots, wherever situated on the solar disk. 6173.55, which is a fine triplet in spots, is a triplet when observed at right angles to the lines of force. But the line \63802.71 is the most interesting of all. In Table I this is classed as a spot doublet. In the spot spectrum the line ap- pears as a triplet, but so decidedly asymmetrical that I supposed the intermediate line to be due to some element other than iron, greatly strengthened in the spot. It now turns out, however, that this is an asymmetrical triplet in the spark, when observed at right angles to the lines of force. Moreover, the displace- ment of the intermediate line from the center is toward the red, both in the spot and in the spark. As soon as a suitable photograph can be taken in a higher order of the grating, it will be possible to measure the asymmetry in the spark, as has already been done in the spot spectrum. The titanium lines \\63803.98 and 6812.46, which are double in spots, are also double in the spark, when observed at right angles to the lines of force. \6064.85, already mentioned as a triplet in spots, with a rather faint central component, is a triplet, with strong central component, in the spark under the above conditions. The titanium spot doublets \\5903.56 and 5938.04 (Table II) have not yet been observed at right angles to the lines of force. These results leave no doubt in my mind that the doublets and triplets in the sun-spot spectrum are actually due to a magnetic field. As I am now design- ing a spectrograph of 75 feet (23 meters) focal length, for use with a tower telescope of 150 feet (46 meters) focal length, I hope it may become possible to investigate small spots, as well as large ones, and to resolve many of the close doublets and triplets in their spectra. Let us sum up the principal parts of Mr. Hale’s experimental evidence: (1) That some spectrum lines which are single in the or- dinary solar spectrum become double in sun spots; (2) that these double lines are found to be circularly polarized in opposite direc- tions; (8) that, as shown by Zeeman, this is a characteristic of spectrum lines produced in a powerful magnetic field and observed along the magnetic lines of force; (4) that the different doublets in 338 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the spots in most cases have almost exactly the same relative separa- tions as have the corresponding lines when observed in the laboratory in a magnetic field; (5) that lines found double in spots near the sun’s limb are also found double when observed in the laboratory at right angles to a magnetic field; (6) that, as shown by Rowland, electric charges in revolution produce a magnetic field; (7) that, as shown by Thomson, it is probable that electrically charged bodies or ions are numerous in the sun; (8) that the spectroheliograph has shown immense spiral configurations suggesting vortices in the higher solar layers and that these vortices are unmistakably con- nected with sun spots; (9) that the vortices are some right handed and others left handed; (10) that in sun spots surrounded by right- handed vortices the polarization of the components of the spec- trum doublets is always found opposite to that for sun spots with left-handed vortices. In view of all this it must be admitted that the existence of magnetic fields in the neighborhood of sun spots is beyond reasonable question, and Mr. Hale’s explanations of them as due to the revolution of electrical charges in vortices have strong support. At the same time it must be kept in mind that the vortical motions are inferred rather than demonstrated, and inferred only for high levels, presumably above the levels of sun spots. Furthermore, spectra of spots near the sun’s limb do not reveal evidence of motion such as would be expected if vortices exist in the spots themselves. Further evidence must therefore be awaited before fully accepting the vortex theory of the production of the magnetic fields which Mr. Hale has discovered. A possible application to terrestrial affairs of this new discovery of magnetism in sun spots springs at once into mind, but according to Mr. Hale’s view the evidence at present is opposed to the con- clusion that the magnetic fields found in sun spots can produce ap- preciable effects on the earth. Nevertheless, it will be almost a matter of regret if further study shall not indicate that the magnetic sun- spot fields are competent to produce the disturbances of terrestrial magnetism which for many years have been known to be intimately related to the prevalence of sun spots. CLIMATIC VARIATIONS: THEIR EXTENT AND CAUSES.2 By Prof. J. W. GREcory, F.. R. S. University of Glasgow. INTRODUCTION. The past variation of climate is an attractive study, as it controls so many questions in geology, geography, and meteorology. But the subject is of especial difficulty, as it deals with the action of complex chemical and physical processes working under conditions and on materials which can be estimated only by the freest speculation. The question may be approached a priori by consideration of the evolution of the atmosphere, as suggested by general chemical prob- abilities; or we may determine from the sedimentary rocks the strength and nature of the geographical agencies that formed them; or we may examine the indirect evidence given by fossils as to the climates under which they lived. The fact of marked local varia- tions in climate is abundantly proved; and it will probably be equally agreed that there is no evidence known to the geologist of any progressive refrigeration of the earth. The idea of the secular cool- ing of the earth is deeply impressed on our terminology; but geolog- ical principles are independent of the theory. The terms suggested by it may always be retained from their historic interest and con- venience, as we still speak of the rising of the sun. Responsibility for the belief in the secular cooling of the earth rests with the astronomers and physicists, from whom geologists have accepted it. Local variations in climates are abundantly established by the former glaciation of temperate regions, the once greater extension of glaciers in tropical regions, and the frequent growth of reef- building corals outside their present geographical limits. But we need not unnecessarily increase the difficulties of the problem by ac- cepting the world-wide range of great climatic changes without con- vincing evidence. Doctor Ekholm takes as the starting point of his valuable paper the ground that “the inquiries of modern geology “Reprinted by permission from Congrés Géologique International. Compte Rendu de la dixiéme session, Mexico, 1906. Mexico City, 1907, pp. 407-426. (Printer’s proofs not seen by author.) 339 340 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. unanimously indicate that all great climatic changes have occurred simultaneously on the whole earth.” ¢ But geological opinion is by no means unanimous on this ques- tion, that the major climatic variations were world-wide in their influence. The amplest evidence in support of the view that a colder climate was once universal is supplied by the Pleistocene glaciations; and it is certain that at one part or another of the Pleistocene period the glaciers of many distant parts of the world were much larger, and that wide areas in the north temperate zone were overwhelmed hy glacial conditions. But there appears to be a steadily growing opin- ion that the glaciers of the different glacial centers did not attain their greatest development at the same time. Thus, the glaciation of Greenland is now at its maximums at an earlier period of the Pleisto- cene Labrador was covered by an ice sheet, which dwindled as that of Greenland developed; and the glaciation of the Canadian Rocky Mountains was probably still earlier than that of Labrador. Sim- ilarly in Europe the conditions of preservation and general aspect of the glacial deposits suggest that the culmination of the Norwegian glaciation was somewhat later than that of the British Isles. Tur GENFRAL UNIFORMITY OF CLIMATES IN THE PAst. The first striking fact in the geological history of climate is that the present climate of the world has been maintained since the date of the earliest, unaltered, sedimentary deposits. The oldest sand- stones of the Scotch Highlands and the English Longmynds show that in pre-Cambrian times the winds had the same strength, the raindrops were of the same size, and they fell with the same force as at the present day. The evidence of paleontology proves that the climatic zones of the earth have been concentric with the poles as far back as its records go; the salts deposited by the evaporation of early Paleozoic lagoons show that the oldest seas contained the same ma- terials in solution as the modern oceans; and glaciations have re- curred in Arctic and, under special geographical conditions, also in temperate regions at various periods throughout geological time. The mean climate of the world has been fairly constant, though there have been local variations which have led to the development of glaciers in regions now ice free, at various points in the geological scale. That there has been no progressive chilling of the earth since the date of the oldest known sedimentary rocks is shown by their lithological characters and by the recurrence of glacial deposits, some of which were laid down at low levels at intervals throughout geolog- @Dr. Nils Ekholm, “ On the variations of the climate of the geological and historical past and their causes,” Quart. Journ. Roy. Met. Soc., Vol. X XVII, 1901, p. 3, CLIMATIC VARIATIONS—GREGORY. 341 e ical time. Thus remnants of a series of glacial deposits, which are probably pre-Cambrian, occur in a series of localities around the Arctic Zone ;* fragments of this early, circum-Arctic glacial chain occur in the north of Norway, as described by Reusch and Strahan; ? in Spits- bergen; ° as some bowlder beds, the descriptions of which are sug- gestive of glacial formation, on the Coppermine River, and in Labra- dor, where, however, according to A. P. Low, they may be Cambrian; and finally on the northern coasts of Siberia, near the estuary of the Lena. The Cambrian system contains an extensive series of glacial deposits, discovered by Mr. Howchin,? running north and south through South Australia, between the latitudes of 32° and 35° S., and as these Cambrian till are interstratified with marine rocks, they were probably formed about sea level. The next proved glacial period is the Upper Carboniferous and perhaps Permian, as proved by the glacial deposits of India, South Africa, Australia, and South America. They were originally as- signed, in Africa and Australia, to the Trias, and subsequently to the Permian, and the Permian age of the South Africa glacial deposits is still asserted by some geologists. But, according to Mr. Seward,’ the glacial deposits at Vereniging—which, according to one theory, are redeposited glacial material, and would, therefore, be the latest of the South African glacial beds—are Upper Carboniferous, and that is the age of the best known and most extensive of the glacial deposits of southeastern Austraha. The Upper Cretaceous has some evidence of glaciation in the Northern Hemisphere, for the oceur- rence of drift ice is the most probable explanation of the bowlders found in the British Chalk; and Professor Garwood found a glaciated pebble on Bunting Bluff, in Spitsbergen, in some conglomerates which are Upper Cretaceous or Lower Cenozoic.’ With the excep- tion of such scraps of evidence, there is no convincing proof of low level glacial action until we reach the Pleistocene. aj. W. Gregory, Quart. Journ. Geol. Soc., Vol. LIII, 1897, p. 155. DA. Strahan, “The raised beaches and glacial deposits of Varanger Fiord,” ibid., Vol. LIII, 1897, pp. 147-155. €The pre-Cambrian glacial bed in Spitsbergen was referred to by Nordensk- jold. I accidentally rediscovered it at Fox Point, on Bell Sound, in 1896, and sketched the best exposed section. (Quart. Journ. Geol. Soc., Vol. LIV, 1898, p. 216.) ¢ Brief reference to these Cambrian glacial deposits is given in Mr. W. How- chin’s paper, “‘ The geology of the Mount Lofty ranges,” Pt. I, Trans. Roy. Soe. South Australia, Vol. XXVIII, 1904, pp. 259, 278, and Pl. XLIII. €A. C. Seward, ‘“ Fossil floras of Cape Colony,” Annals South Africa Mu- seum, Vol. IV, Pt. I, 1903, p. 101. f Quart. Journ, Geol. Soc., Vol. LIV, 1898, p. 217, 342 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. EXAGGERATED ESTIMATES OF CLIMATIC CHANGES. The range of climatic variations in the past has been often greatly exaggerated, thereby leading to the apparent necessity for revolution- ary changes in former meteorological conditions. But the climatic changes we have to explain appear to have been either local in area or moderate in degree. The opinion that there have been fundamental changes in climate is based mainly upon the evidence of former glaciations and on the supposed existence of tropical climates in the arctic regions. That tropical or subtropical conditions once prevailed in the Arctic Circle is affirmed on the reported occurrence there of fossil coral reefs and tropical vegetation. I have previously quoted evidence to show that this view is greatly exaggerated.* One notice of that paper described its views as “ trés hardie,” but I am not aware of any refutation of its conclusions. The idea of the former tropical condition of Greenland is still confidently asserted. Thus Doctor Ekholm® refers to the nearly tropical climate that prevailed in the arctic regions during the Cretaceous age, when he estimates that the mean temperature was 36° F. higher than during the Pleistocene. But so far as I know the evidence there is no proof that the arctic regions ever had a sub- tropical or even a warm, temperate climate. THE EVIDENCE OF FOSSIL CORALS. The Arctic Ocean has been described as having been a coral sea in Silurian and Carboniferous times. This view led to Blandet’s sugges- tion—well known by its advocacy by Sir John Murray—that in Paleozoic times light and heat were equally distributed throughout the world; and also to the theories that the heat from the sun is diminishing owing to the smaller size of the sun, as suggested by Helmholtz, or to its lower intensity, as advocated by Dubois. But the fossil faunas of the arctic seas all show the dwarfing effect of unfavorable conditions when compared to the contemporary faunas in the seas to the south. Corals of reef-building genera have lived in the arctic regions; but I have seen no arctic specimens larger than nodules which could have grown in a cool sea. The asserted existence of arctic coral reefs in Silurian times was based on a collection made in Grinnell Land, which is now in the British Museum. But the specimens show noth- ing more than the growth of small nodular corals, such as may have grown in a temperate sea. Paleozoic corals have also been found in the Timan-Urals and in the Silurian rocks of the New Siberian a“ Some problems of Arctic Geology. II. Former arctic climates.” 6 Ekholm; op. cit., pp. 25, 26. CLIMATIC VARIATIONS—GREGORY. 343 Islands; but in both cases the evidence shows that the coral faunas were stunted in comparison with those of the contemporary seas to the south. Numerous simple and simply branched corals, associated with thick growths of calcareous alge, grow to-day in the northern seas. Dead branches of Lophoheha are so common on one bank in the Christiania Sound (latitude 58° N.) that it has been described as a Pleistocene coral reef. Small nodules of corals, of reef-building genera, such as Plesiastrwa, live at present in the cold seas of south- ern Australia, far to the south of the region of coral reefs. Hence I feel justified in repeating the view expressed in 1897, that the evidence of the fossil corals from the Silurian rocks of Greenland and Great Britain shows “ that there was almost as great a difference between the temperature of the sea in the areas as there is to-day.” ¢ The evidence of the fossil corals is supported by that of the arctic marine faunas of all geological periods. Their most striking char- acteristics in the past are their characteristics of to-day, and show “that all through geological time the northern faunas have lived under the blight of arctic barrenness.” ? THE EVIDENCE OF THE FOSSIL FLORAS. The fossil floras of the Arctic, as identified by Heer, have been used as the basis of the attractively sensational theory that Greenland enjoyed a tropical climate in Miocene times and a tropical or sub- tropical climate in Cretaceous times. But the evidence so far adduced appears to be quite insufficient to justify this view. The most char- acteristically tropical of the plants claimed to occur in Greenland are the palms; but the fossil arctic palms have now been dismissed as based on erroneous identifications. Much weight has also been at- tached to some fossil tree ferns of the genus Dicksonia, from the Cretaceous of Greenland. But the best-known living species of that genus 1s Dicksonia antarctica, which occurs in southern New Zealand; and Dicksonia also lives on the high “ Snowy Plains” of the Victo- rian Highlands, where it is sometimes buried under snow for four or five months in the year. Hence the existence of fossil tree ferns, espe- cially of the genus Dicksonia, would certainly not imply tropical con- ditions. Heer’s identifications have been contemptuously rejected by many later botanists, including Dr. Robert Brown, Dr. Starkie Gard- ner, and Professor Nathorst. Most of Heer’s determinations were based upon leaves, which give no data for generic identification. Nor does the existence of leaf beds in the Arctic prove anything more than local geographical changes, for leaves grow with remarkable rapidity and luxuriance within the Arctic Circle, under the influence of the 2Op. cit., Nature, Vol. LVI, 1897, p. 352. oTbid., p. 352. 88292—sm 1908——23 344 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. continuous daylight of summer. That dense foliage grows upon the moraines of Alaska is well known from the photographs, taken upon the Malaspina Glacier, published by I. C. Russell; 7 and in the same district forests of fir trees, growing on moraines, are being now trans- ported by the Alaskan glaciers. The fossil tree trunks in arctic coal seams would supply better evi- dence of a change of climate than the fossil leaves, if there were evidence to prove that the trees had grown in situ. The view that the three months’ darkness of winter would be fatal to tree growth is now recognized as untenable; but it is a fact that forests do not occur north of 70°, although fossil tree trunks have been found beyond that latitude. But these tree trunks were probably carried north as drift- wood.. Robert Brown has described the Disco plant beds and come to the definite conclusion that the plants had not grown in situ. Baron von Tol has published photographs of plant beds associated with ancient ice in northern Siberia, but his photographs show the roots of nothing larger than shrubs. In 1896 I had occasion to mine some hundredweights of coal from the seam of Advent Bay, Spitsbergen (latitude 78° 15’ N.), and the section exposed gave no evidence that the coal had been formed from vegetation that had grown in situ. In many places the arctic shores are white with a litter of pine, fir, and larch logs, which have been floated down the Siberian rivers, drifted across the Arctic Ocean, and been thrown upon the shores.? These accumulations of driftwood become covered by the growth of moss, saxifrages, and arctic willows; and if then buried beneath sheets of sediment would form arctic coal seams, made from timber that had grown in central Asia. The paleobotanical evidence that the arctic regions had a tropical or subtropical climate in the Cretaceous 1s inadequate, and it is con- tradicted by the Paleozoological evidence of the contemporary marine deposits. The Cretaceous marine beds in Greenland have a stunted fauna, which has no tropical or subtropical characters. The British Chalk sea was sufficiently cold for drift ice to carry bowlders as far south as London and its fauna is decidedly nontropical. The Chalk sea was of moderate depth, but its crinoids were small and scarce, its corals. were small and simple, and its mollusca indicate a cooler sea than do the Hippurites, etc., of the Mediterranean beds. In the Lower Cretaceous beds of British Isles there are abundant shallow sea and shore deposits, but there are no coral reefs, and the general aspect of the fauna indicates a sea decidedly colder than that of the aT. C. Russell, “ Second expedition to Mount St. Elias,” Thirteenth Ann. Rep. U.S. Geol. Surv., 1898, Pl. XIV. +A photograph showing one of these timber-strewn beaches has been pub- lished in the ‘‘ Voyage de la Manche,” Pl. V, 1894. CLIMATIC VARIATIONS—GREGORY. 345 Jurassic. The British Cretaceous marine deposits indicate the prev- alence of a cool temperate, and those of Greenland an arctic, climate, in the period when, on the unreliable evidence of fossil leaves, we are asked to believe the conditions in Greenland were tropical or sub- tropical. The paleontological evidence at present available does not throw on us the burden of explaining why the Arctic had a tropical cli- mate, for it simply contradicts assertion as a matter of fact. GLACIATION Dur to Locau CLIMATIC VARIATIONS. The second line of evidence used to prove intense, widespread climatic changes is the occurrence of glacial deposits in the temperate zones and the greater extensions of tropical glaciers. But this evi- dence has also been used to indicate more extreme changes than are necessary to explain the facts. Thus, it appears to be sometimes con- sidered that the glacial beds of South Africa, India, and Australia prove that in one epoch of the Upper Paleozoic the whole area of the Indian Ocean, from 30° N. latitude in India to more than 40° S. in Tasmania was undergoing glaciation. The difficulty of explaining former glaciations has been greatly increased by such assumptions as that they were due to the develop- ment of a severer climate at the same time throughout the world. There is not yet adequate evidence that the former glaciations were accompanied by a universal change of climate. It is true that there is evidence of a more extensive Pleistocene glaciation in many regions of the world, including Mount Kenya, upon the equator in British East Africa, Mount Kosciusko in southeastern Australia, western Tasmania, the South Island of New Zealand, Patagonia, and a belt practically all across the temperate regions of the Northern Hemi- sphere. Accordingly it is claimed, as by Ekholm (op. cit., p. 34), that the snow line was everywhere 1,000 meters lower at the time when Europe had its “Great Ice Age.” But there are too many cases in which evidence of such former extension has been sought for in vain, for a universal lowering of temperature in the Pleistocene to be accepted as yet finally established. In the North Island of New Zealand there is no evidence of any former glaciation, and had its existing snowfields extended more than 3,000 feet lower, they should have left some traces of so great growth. D’Orbigny and Whymper both failed to find any evidence of any greater extension of the exist- ing glaciers on the equatorial Andes than could be explained by a local variation in the winds. In equatorial Africa no Pleistocene glacial deposits have been found, except on the dwindling summits of the highest mountains; and the coastal raised beaches give no evidence of any contemporary. reduction in the temperature of the 346 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. adjacent seas. There is no evidence of any Pleistocene glaciation on the mainland of Australia, except on the highest summit of the Australian Alps; and though Mount Kosciusko, which is now 7,256 feet above sea level, in a region with a 60-inch rainfall, had once a few small glaciers, there is no evidence in Australia generally of a colder Pleistocene climate. In fact the early Pleistocene or Pliocene fauna of central Australia indicates the extension then of the tropical fauna of northern Australia into the temperate regions of the Conti- nent. Neither the flora nor fauna of the Pleistocene deposits of Victoria indicates a colder climate than that of the present time. The glaciations themselves, moreover, though often very extensive, appear to have been always local.. Thus those of the Pleistocene in the Northern Hemisphere were grouped around a series of centers, which are not always in particularly high latitudes. In North America there appear to have been three glacial centers, that of the Canadian Rocky Mountains in latitude 55° to 60°; that of eastern Canada in latitude 50° to 55°, and with its southern edge extending to latitude 42° N.; and that of Greenland of which the center is from Oe toma> IN: In Europe the glaciation of the British Isles extended as far south as latitude 52°; that of Scandinavia, from a center between latitude 60° and 65° N., overrode the country as far south as northern Germany in latitude 53° N.; and the other centers farther south developed where high mountains, such as the Alps, occurred near warm seas. Causes or Cirmatic VARIATIONS. If it be accepted that former climatic changes involve less extreme changes of temperature than have been generally assumed, and that we are not called on to explain former tropical forests in the arctic lands, or fossil coral reefs in the arctic seas, or occasional universal refrigerations of the earth, then the problem of climatic variations is greatly simplified. THE ELEVATION THEORY. Several explanations, attractive from their simplicity, may then be at once dismissed. The theory of the migrations of the poles into temperate regions, although supported by Oldham and Penck for the Upper Paleozoic glaciation, is contradicted by the evidence of pale- ontology; and the explanations it would give of world-wide changes are not required. The once popular theory that ice caps have been produced by the greater elevation of the land may be abandoned, as opposed to meteorological principles, and as implying a reversal of the facts, glaciations having so often accompanied periods of greater submergence of the land, and milder climates having coin- CLIMATIC VARIATIONS—GREGORY. 347 cided with periods of emergence; and it would be quite inapplicable to the Upper Paleozoic glaciation of Australia, of which the glacial deposits were in places submarine. THE OBLIQUITY OF THE ECLIPTIC. Nor, in spite of the fresh use made of it by Ekholm and Dickson, does the variation in the obliquity of the ecliptic appear to help mate- rially; for all the influences of this agency are open to the funda- mental objection that variations in obliquity recur at what, geolog- ically speaking, are short and frequent intervals; whereas ancient glaciations happened but seldom, and were apparently irregular in their time of return. VARIATIONS IN THE CARBONIC ACID CONTENT OF THE ATMOSPHERE. The view that now seems most popular explains the major climatic changes by variations in the powers of selective absorption of heat by the atmosphere. The change is attributed either to variations in the amount of aqueous vapor as urged by de Marchi® or of carbon dioxide as advocated by Svante Arrhenius,’ and recommended to us by the brilliant advocacy and high authority of Prof. T. C. Cham- berlin.¢ The aqueous vapor theory has been adequately disposed of by Arrhenius, whose alternative is especially attractive, as it demands comparatively small differences of temperature and very modest vari- ations in the amount of carbonic acid. Thus he calculates that an increase of the carbonic acid from 0.03 to 0.09 per cent would give the polar regions a temperate climate, by a rise of from 12° to 16° F. Nevertheless, this theory—that former colder periods were due to a reduction of the carbonic acid in the air and warm periods to an in- crease in its amount—is faced by objections which I venture to think still inadequately answered. No one is likely to deny the possibility of great variations in the former composition of our atmosphere. The theories of Koene (1856), Phipson (1893-94), or Stevenson (1902) ,@ that the primitive @De Marchi, “ Le Cause dell’era Glaciale,’ Pavia, 1895. +S, Arrhenius, ‘‘ On the influence of carbonic acid in the air upon the tempera- ture of the ground,” Phil. Mag., ser. 5, Vol. XLI, 1896, pp. 287-276. eT. C. Chamberlin, “A group of hypotheses bearing on climatic changes,” Journ. Geol., Vol. V. 1897, pp. 676-683; “ The influence of great epochs of lime- stone formation upon the constitution of the atmosphere,” ibid., Vol. VI, 1898, pp. 609-621. @J. Stevenson, “The chemical and geological history of the atmosphere,” Phil. Mag., ser. 5, Vol. L, pp. 312-823, 399-407; also Pt. II, “ The composition and extent of the atmosphere in very primitive times,’ Phil. Mag., ser. 6, Vol. IV, 1902, pp. 448-451. 348 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. atmosphere was many times larger than at present, was rich in car- bonic acid, and had no free oxygen, may be inapplicable to any part of geological time; though they may very likely be true for the first formed atmosphere, long before the date of the oldest known sedi- mentary rocks. From the earth’s surface we look up through zones of atmosphere, in which the oxygen and carbonic acid steadily di- minish, and the minute proportion of hydrogen at sea level increases, until 50 miles high the air consists practically of hydrogen alone.? The aurora flares above us in a mixture of hydrogen and neon; and as there is evidence of such fundamental variations in the atmos- phere in space, there may well have been marked changes in time. There are so many agents pouring carbonic acid into the air and so many others withdrawing it that it would be strange if the present equilibrium had always been maintained. The oceanic control. Nevertheless it must not be forgotten that the ocean, as shown by Schloesing,’ supported by the weighty experiments of Dittmar, con- trols the amount of carbonic acid in the atmosphere. If the amount of carbonic acid in the atmosphere is diminished, the bicarbonates in the sea are dissociated; the gas thus liberated is poured into the air until the former equilibrium between the tension of the carbonic acid in the atmosphere and in the sea is reestablished. Hence, a reduction of carbonic acid in the air is automatically followed by the discharge of nearly as large a quantity from the sea; so that any reduction is distributed between the air and the ocean. Any increase of carbonic acid in the atmosphere is followed by the reverse change, and only one-sixth of the amount poured into the atmosphere is retained there. Tt is true that great variations in the relative extent of sea and land would affect the dissociation pressure of the bicarbonates in the sea, but it would require a great reduction in the area of sea surface to affect the equilibrium appreciably. Possible evidence from paleontology. Efforts may be made to ascertain from paleontological evidence whether the atmosphere has recently altered its composition. This line of inquiry does not promise reliable conclusions, owing to the powers of adaptation of both animals and plants to changes in the atmosphere. An increase in carbonic acid, provided it be not accom- @Sir J. D. Dewar, ‘‘The problems of the atmosphere,’ Proc. Roy. Inst., Vol. XVII, 1902, p. 226. 4 Schloesing, “‘Sur la constance de la proportion d’acide carbonique dans - Yair,’ Compt. Rend., Vol, 90, 1880, p. 140. CLIMATIC VARIATIONS—GREGORY. 349 panied by organic solution, from 3 parts to 100 parts in 10,000—an increase ten times as great as the maximum considered by Arrhe- nius—is inappreciable to man. The ordinary data of mine ventila- tion and the experimental results of Dr. J. S. Haldane and Dr. Lor- raine Smith show that men can stand, without serious inconvenience, an increase of carbonic acid to even 400 parts in the 10,000; and as there is no probability of temporary variations to any such degree, a slow increase in the carbonic acid contents of the air would probably have a greater indirect effect upon animals through its action on the temperature than by its direct effect on respiration. Noncoincidence of dates. The main objection to the atmospheric variation theory is that it does not explain the facts of historical geology. And geologists, as the historians of the earth, test theories whenever possible, by their agreement with contemporary records. The influence of variations of the carbonic-acid contents of the atmosphere on temperature should affect the whole world simul- taneously.t. The change need not be the same in all latitudes, as is shown by Arrhenius’s tables; and also by the variation in the pro- portion of carbonic acid with latitude, which is rendered probable by the evidence adduced by Letts and Blake.” Nevertheless, it might be expected that corresponding positions in the two hemispheres should be almost equally affected. There is, however, no evidence of a glaciation in Europe?’ in Upper Carboniferous or Permian times corresponding to that of South Africa or Australia, in spite of the unusually extensive knowl- edge of the land conditions of that period. The Indian glaciation of Pokaran in latitude 25° N., and of Chanda in latitude 19° N., may correspond to that of South Africa from latitude 24° S. to 34° S., or of southeastern Australia from latitude 30° S. to 40° S. But the general collapse of the supposed Permian glacial conglomerates of the English Midlands, and the unconvincing evidence collected to support Carboniferous glaciation in France, as by Julien,? leaves us “Tt is sure that according to the results of Muntz and Aubin there is at present a difference in the amounts of carbonic acid in the air of the Northern and Southern hemispheres; they estimate the mean amount as 0.028 per cent in the Northern and 0.027 per cent in the Southern. This difference follows from the greater area of sea in the Southern Hemisphere, which can hardly have been much greater at any previous period. oe. A. Letts and R. F. Blake, “ The carbonic anhydride of the atmosphere,” Sci. Proc. Roy. Dublin Soc., Vol. EX, 1900, pp. 179-180. ¢There is some evidence of glacial beds of this period on the east of the Ural Mountains. @A, Julien, “Anciens glaciers de la Période Houillére dans le Plateau Central de la France,’ Ann. Club Alpin Frangais, Vol. X XI, 1894, pp, 28, 350 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. =- with no evidence of any refrigeration of Europe at the date of the Gondwana-Land glaciation. Again, the Upper Paleozoic glacial deposits of southeastern Aus- tralia do not appear to have been synchronous in all the localities. The glacial deposits on the northern coast of Tasmania have been shown by Kitson ¢ to be of the age of the Mersey Coal Measures of Tasmania, which may be correlated with the Lower or Greta Coal Measures of New South Wales. The Victorian glacial deposits are probably on approximately the same horizon, which agrees with some of those of New South Wales. But, according to David,’ there were glacial deposits in New South Wales at the following different stages in the Permo-Carboniferous: Branxton Glacial beds in the Upper Marine series. Greta Coal Measures. Shales with occasional erratics in the Lower Marine series. Lochinvar Glacial Beds at the base of the Lower Marine series. Again, whatever view may be held on the controversy as to the occurrence of warm interglacial periods during the Pleistocene gla- ciation of Europe, it will be generally admitted that considerable oscillations occurred in the extent of ice. Thus the evidence in the British Isles strongly supports the view that after the maximum glaciation there was a reduction in the extent of the ice, and then, after some interval, a fresh advance of valley glaciers. And such interludes, of which in the British Isles there may have been more than one, would appear to require considerable variations in the amount of carbonic acid in the atmosphere, repeated within a short period of time. Weighty evidence is also given against Arrhenius’s theory by the dates of the glaciations, as they do not correspond with those at which variations in the carbonic-acid contents of the atmosphere would be most probable. Widespread volcanic eruptions offer the simplest explanation of the addition of large volumes of carbonic acid to the atmosphere; but periods of intense volcanic activity do not appear to have been always followed by glacial epochs. The great volcanic periods—the Devonian, the Permian, the Upper Cretaceous, the Eocene, and the Oligocene—were not followed by marked developments of glaciers. The one coincidence is in the case of the Upper Carboniferous or Permian glaciation of Gondwana Land. The Pleistocene glaciation followed a period in which vol- canic action was powerful, but was probably less than at other periods not followed by glacial advance. aA, BH. Kitson, “ On the occurrence of glacial beds at Wynyard, near Table Cape, Tasmania,” Proc. Roy. Soc. Victoria, new ser., Vol. XV, 1902, p. 34. oT, W. E. David, “Discovery of glaciated boulders at base of Permo- Carboniferous system, Lochinvar, New South Wales,” Journ. Roy. Soc. New South Wales, Vol. XX XIII, 1899, pp. 154-159. CLIMATIC VARIATIONS—GREGORY. oo: Again, with the reverse case. Periods of especially active con- sumption of carbonic acid were not followed by glacial epochs. As Professor Chamberlin has shown, the most extensive removal of carbonic acid from the atmosphere was probably during the forma- tion of sheets of limestone, while coal seams contain a smaller but still large amount of carbon obtained from the carbonic acid of the air. The great limestone building periods fixed enormous quantities of carbonic acid, which must have come from the atmosphere, be- cause if obtained from the sea its fixation must have led to the trans- ference of a fresh supply from the atmosphere. The greatest lime- stone periods are probably the Lower Carboniferous, the Jurassic, the Upper Cretaceous, and the Eocene and the Miocene. But none of them was a period of active glaciation. Speaking generally, they appear to have been warmer than the average. Thus in the British Isles we find unusually well-developed growths of corals in the Lower Carboniferous and the Jurassic. The British Eocene flora included plants suggestive of a warmer climate than that of the present time, while the marine faunas of the Middle Cenozoic in Europe and southern Austraha indicated that those seas were then warmer than they are to-day. The Upper Cretaceous alone gives any indications of cold conditions, as shown by the probably ice-borne bowlders in the English Chalk and the temperate aspect of its fauna; but the oft- stated view that Greenland then enjoyed a subtropical climate rests on evidence which at least does not support the idea that the period was one of universal severity. The apparent independence of the times of limestone formation and glaciations is further shown by the fact that the chief glacial periods—the Cambrian in Australia and eastern Asia, the Upper Carboniferous or Permian of South Africa, India, and Australia, and the Pleistocene in the Northern Hemi- sphere—were not periods of great limestone formation. CHANGES IN TEMPERATURE GRADIENT OF THE ATMOSPHERE. The influence of changes in the composition of the atmosphere is also the basis of Dickson’s theory.* But he traces its influence not through the variations in heat absorption by the atmosphere, but through the variations in the temperature gradient from the Tropics to the polar regions. Dickson’s paper is of value from its clear state- ment of the facts showing that a development of glaciation is possible with only a small change in mean temperature. Dickson appeals to a former difference in the temperature gra- dient between the polar and equatorial regions; he attributes the change in gradient either to the changes that are always in progress aH. N. Dickson, ‘‘ The mean temperature of the atmosphere and the causes of glacial periods,’ Geogr. Journ., Vol. XVIII, 1901, pp. 516-528. 352 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. in the obliquity of the ecliptic, or to variations in the carbonic acid in the air. He shows that either would give effects of the magnitude required; but it seems doubtful whether either will agree with the records of historical geology ; for as regards the first cause, the change in the obliquity is, geologically speaking, a short and constant oscilla- tion; and, as to the second, as it rests on the variation of carbonic acid, it is open to the same objections as to those of Arrhenius’s theory. CHANGES IN ATMOSPHERIC CIRCULATION. That the explanation of glacial periods is to be sought in changes in the circulation of the atmosphere resulting from geographical changes has been several times suggested, in accordance with Bu- chan’s results.* This principle has received its fullest application to a specific case by Harmer ® to the Pleistocene climate of north- western Europe. And, moreover, Dickson has shown how the distri- bution of the glaciations in that case corresponds with what would be expected if they were due to differences in atmospheric circulation. Such meteorological changes would be quite inadequate to explain the occurrence of a tropical climate in the arctic regions, but they would account for changes of temperature of a few degrees, and for glaciations by local concentrations of the snowfall. The difference between the climates of western Europe and eastern America is ob- viously due to meteorological conditions, resulting from geographical position. The differences on the two coasts of the North Atlantic were naturally first attributed to the influence of ocean currents; but with our present knowledge as to their feebleness and the bending of the Gulf Stream off Newfoundland, ocean currents may be dismissed as a very subordinate factor. A different distribution in air pressure resulting in a different circulation of the wind would probably be a more effective cause, and appears to me at present to offer the best prospects of a satisfactory solution to the problem. It is the only explanation that seems to agree with the essential facts, viz, the development of glaciation from scattered centers, and at somewhat different dates, and the apparent independence of the glaciations in distant continents, and their apparent direct dependence on a par- ticular adjustment of meteorological conditions. The slow march of glaciation across North America and possibly also across Europe is intelligible on this hypothesis, and there is no reason, on that theory, to expect coincidence of glaciations in the Northern and Southern hemispheres. The former glacial extensions @¥or instance, I endeavored to show in 1894 that the more extensive glacia- tion of Mount Kenya was due to a local difference in the atmospheric pressure due to the former greater height of this denuded volcano. (‘‘'The glacial geology of Mount Kenya,” Quart. Journ. Geol. Soc., Vol. L, 1894, pp. 527-530.) bm. W. Harmer, Quart. Journ. Geol. Soc., Vol. LVII, pp. 405-472. CLIMATIC VARIATIONS—GREGORY. 353 in Australasia can thus be easily explained; for the evidence, so far, appears to be only convincing in localities either on the edge of the antarctic regions or in local areas where the meteorological conditions are unusual. New Zealand is often quoted as having been glaciated, either in the Pleistocene or at the same time as the glaciation of Kurope. But it should be remembered that there is no evidence yet of any glaciation in the North Island of New Zealand, and the former range of the glaciers in the South Island has been consid- erably exaggerated. On the western slope of the South Island gla- ciers in latitude 43° 20’ S. still come down to the level of 600 feet above the sea; and it is along that coast with its intense rainfall that the former ice extension is most clearly shown. In Tasmania the Pleistocene glaciation resulted from a heavy snowfall along the western edge of the Central Plateau, and the low moraines yet proved, occur only in the valleys leading down to the western coasts; but on the mainland of Australia the evidence of former glaciation is very scanty. Its existence has been finally established by the work of David and Pittman, on Kosciusko; but the numerous cases of Pleisto- cene glaciation that have been asserted in Victoria can not be main- tained. I have visited all but two, and saw no evidence of glacial action in any of them; and the evidence relied on in both the places I have not seen has been described by others as explicable by non- glacial agencies. The Permian or Carboniferous glaciations of South Africa, India, and Australia being in low latitudes and ranging down to sea level in New South Wales and in the Salt Range appears at first sight to be the most difficult problem in paleometeorology. But the question is simplified by the following considerations: 1. The geographical conditions of the areas concerned were very different from those of the present day. 2. The three best-known glacial centers occurred on the borders of the old continent of Gondwana Land, farthest from the equator, and they were probably all near mountainous country, facing seas open to the colder zones. 3. The only cases where the glacial deposits reached the sea were in the areas farthest from the Tropics, and probably most exposed to cold winds. 4, Icebergs occasionally now reach almost to the Tropics; thus in April, 1894, one was seen in the South Atlantic in latitude 26° 30’ S. 5. The glacial deposits appear to have been absent from the more tropical parts of Gondwana Land, as they disappear toward the north in both Australia and in South Africa. Both in Australia and South Africa the glaciation occurred in areas where mountains existed near the sea. In southeastern Aus- tralia there is ample evidence that a wide Upper Paleozoic sea lay to 354 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the east of a gulf to the northwest of Australia. In all probability there was a large extent of land stretching southward and cutting off the cold southern ocean from the seas, which extended southward from the Tropics. Under such conditions the wind systems would have traversed the Australian lands upon a different path from that which they follow now, and they would not have advanced so steadily. The winds would have carried large quantities of moisture southward, from the warm northern seas, and it would have been pre- cipitated on the mountains of that period, which were kept cold by southerly winds, chilled by their passage over the former extension of Australia to the south. In South Africa and South America the question is simpler, as there is no proof of the glacial deposits hav- ing been laid down at sea level; they may have been formed upon the flanks of mountain areas, kept abundantly supplied with snow, by west winds blowing in from the adjacent oceans. In India the condi- tions were probably meteorologically similar, the glaciation having been on the cooler edge of Gondwana Land, where it was bounded by a temperate sea; and though the glaciers ranged into the Tropics in southern India as far south as latitude 17° 20’ N., there is no proof that they occurred there at low levels. It appears, therefore, probable that variations in climate, which have been established on adequate evidence, can be accounted for by differences in atmospheric circulation, due to different distri- butions of land and water. All the evidence available regarding the Upper Paleozoic glaciation of Gondwana Land appears to be con- sistent with the view that the glaciers developed, like those of the Pleistocene glaciation of North America and of northwestern Europe, in a number of scattered localities, where mountains oc- curred beside the sea, and where the meteorological conditions pro- duced a high snowfall and a low summer temperature. URANIUM AND GEOLOGY.¢ [With 1 plate.] By Prof. JouHn Jony, M: A., D. Sc, EF. R. S. INTRODUCTION. In our day but little time elapses between the discovery and its ap- plication. Our starting point is as recent as the year 1903, when Paul Curie and Laborde showed experimentally that radium steadily maintains its temperature above its surroundings. As in the case of many other momentous discoveries, prediction and even caleu- lation had preceded it. Rutherford and McClung, two years before the date of the experiment, had calculated the heat equivalent of the ionization effected by uranium, radium, and thorium. Even at this date (1903) there was much to go upon, and ideas as to the cosmic influence of radio-activity were not slow in spreading.” Tam sure that but few among those whom I am addressing have seen a thermometer rising under the influence of a few centigrams of a radium salt; but for those who pay due respect to the principles of thermodynamics, the mere fact that at any moment the gold leaves of the electroscope may be set in motion by a trace of radium, or, better still, the perpetual motion of Strutt’s “radium clock,” is all that is required as demonstration of the ceaseless outflow of energy attending the events proceeding within the atomic systems. Although the term “ ceaseless ” is justified in comparison with our own span of existence, the radium clock will in point of fact run down and the heat outflow gradually diminish. Next year there will be less energy forthcoming to drive the clock, and less heat given off by the radium by about the one three-thousandth part of what now are evolved. As geologists, accustomed to deal with millions of years, we must conclude that these actions, so far from being ceaseless, are @ Address to the geological section of the British Association for the Ad- vancement of Science, at Dublin, 1908. Reprinted by permission, with correc- tions by the author. 5 See letters appearing in Nature of July 9 and September 24, 1903, from the late Mr. W. E. Wilson and Sir George Darwin referring to radium as a solar constituent, and one from the writer (October 1, 1903) on its influence as a ter- restrial constituent. 355 356 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. ephemeral indeed, and that if importance is to be ascribed to radium as a geological agent we must seek to find if the radium now perish- ing off the earth is not made good by some more enduringly active substance. That uranium is the primary source of supply can not be regarded as a matter of inference only. The recent discovery of ionium by Boltwood serves to link uranium and radium, and explains why it was that those who sought for radium as the immediate offspring of uranium found the latter apparently unproductive, the actual rela- tion of uranium to radium being that of grandparent. But even were we without this connected knowledge, the fact of the invariable occurrence in nature of these elements, not only in association, but in a quantitative relationship, can only be explained on a genetic con- nection between the two. This evidence, mainly due to the work of Boltwood, when examined in detail, becomes overwhelmingly con- vincing. Thus it is to uranium that we look for the continuance of the sup- plies of radium. In it we find an all but eternal source. The frac- tion of this substance which decays each year, or, rather, is trans- formed to a lower atomic weight, is measured in tens of thousands of millionths; so that the uranium of the earth one hundred million years ago was hardlly more than 1 per cent greater in mass than it is to-day. As radio-active investigations became more refined and extended, it was discovered that radium was widely diffused over the earth. . The emanation of it was obtained from the atmosphere, from the soil, from caves. It was extracted from well waters. Radium was found in brick-earths, and everywhere in rocks containing the least trace of demonstrable uranium, and Rutherford calculated that a quantity of radium so minute as 4.610" grams per gram of the earth’s mass would compensate for all the heat now passing out through its surface as determined by the average temperature gradients. In 1906 the Hon. R. J. Strutt, to whom geology owes so much, not only here but in other lines of advance, was able to announce, from a systematic examination of rocks and minerals from various parts of the world, that the average quantity of radium per gram was many times in ex- cess of what Rutherford estimated as adequate to account for ter- restrial heat loss. The only inference possible was that the surface radium was not an indication of what was distributed throughout the mass of the earth, and, as you all know, Strutt suggested a world deriving its internal temperature from a radium jacket some 45 miles in thickness, the interior being free from radium.¢ My own experimental work, begun in 1904, was laid aside till after Mr. Strutt’s paper had appeared, and a valued correspondence 4@Proc. Roy. Soc. Vol. LXXVII, p. 472, and Vol. LXXVIII, p. 150. . URANIUM AND GEOLOGY—JOLY. 357 with its distinguished author was permitted to me. This address will be concerned with the application of my results to questions of geo- logical dynamics. Did time permit I would, indeed, like to dwell for a little on the practical aspect of measurements as yet so little used or understood ; for the difficulties to be overcome are considerable and the precau- tions to be taken many. The quantities dealt with are astoundingly minute, and to extract with completeness a total of a few million millionths of a cubic millimeter of the radio-active gas—the emana- tion—from perhaps half a liter or more of a solution rich in dis- solved substances can not be regarded as an operation exempt from possibility of error; and errors of deficiency are accordingly frequently met with. Special difficulties, too, arise when dealing with certain classes of rocks. For in some rocks the radium is not uniformly diffused, but is concentrated in radio-active substances. We are in these cases assailed with all the troubles which beset the assayer of gold who is at a loss to determine the average yield of a rock wherein the ore is sporadically distributed. In the case of radium determinations this difficulty may be so much the more intensified as the isolated quanti- ties involved are the more minute and yet the more potent to affect the result of any one experiment. There is here a source of discrep- ancy im successive experiments upon those rocks in which, from metamorphic or other actions, a segregation of the uranium has taken place. With such rocks the divergences between successive results are often considerable, and only by multiplying the number of experi- ments can we hope to obtain fair indications of the average radio- activity. It is noteworthy that these variations do not, so far as my observations extend, present themselves when we deal with a recent marine sediment or with certain unaltered deposits wherein there has been no readjustment of the original fine state of subdivision, and even distribution, which attended the precipitation of the uranium in the process of sedimentation. But the difficulties attending the estimation of radium in rocks and other materials leave still a large balance of certainty—so far as the word is allowable when applied to the ever-widening views of sci- ence—upon which to base our deductions. The emanation of radium is most characteristic in behavior; knowledge of its peculiarities en- ables us to distinguish its presence in the electroscope, not only from the emanation of other radio-active elements but from any accidental leakage or inductive disturbance of the instrument. The method of measurement is purely comparative. The cardinal facts upon the strength of which we associate radium with geological dynamics, its development of heat, and its association with uranium are founded in the first case directly on observation and in the second on evidence so 358 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. strong as to be equally convincing. Recent work on the question of the influence of conditions of extreme pressures and temperatures on ‘the radio-active properties of radium appear to show that, as would be anticipated, the effect is small, if indeed existent. As observed by Makower and Rutherford, the small diminution noticed under very extreme conditions in the y radiation possibly admits of explanation on indirect effects. These observations appear to leave us a free hand as regards radio-thermal effects, unless when we pursue speculations into the remoter depths of the earth, and even there, while they remain as a reservation, they by no means forbid us to go on. The precise quantity of heat to which radium gives rise, or, rather, which its presence entails, can not be said to be known to within a small percentage, for the thermal equivalent of the radio-active energy of uranium, actinium, and ionium, and of those members of the ra- dium family which are slow in changing, has not been measured directly. Professor Rutherford has supplied me, however, with the calculated amount of the aggregate heat energy liberated per second by all these bodies. In the applications to which I shall presently have to refer I take his estimate of 5.610 calories per second as the constant of heat production attending the presence of one gram of elemental radium. To these words of introduction I have to add the remark, perhaps obvious, that the full and ultimate analysis of the many geological questions arising out of the presence of radium in the earth’s surface materials will require to be founded upon a broader basis than is afforded by even a few hundred experiments. The whole sequence of sediments has to be systematically examined; the various classes of igneous materials, more especially the successive ejecta of volcanoes, fully investigated. The conditions of entry of uranium into the oceanic deposits has to be studied, and observations on sea water and deep-sea sediments multipled. All this work is for the future; as yet but little has been accomplished. THE RADIUM IN THE ROCKS AND IN THE OCEAN. The fact, first established by Strutt, that the radium distributed through the rock materials of the earth’s surface greatly exceeds any permissible estimate of its internal radio-activity has not as yet re- ceived any explanation. It might indeed be truly said that the con- centration of the heaviest element known to us (uranium) at the sur- face of the earth is just what we should not have expected. Yet a sim- ple enough explanation may be at hand in the heat-producing capacity of that substance. If it was originally scattered through the earth- stuff, not in a uniform distribution ,but to some extent concentrated fortuitously in a manner depending on the origin of terrestrial ingre- URANIUM AND GEOLOGY—JOLY. 359 dients, then these radio-active nuclei heating and expanding beyond the capacity of surrounding materials would rise to the surface of a world in which convective actions were still possible, and, very con- ceivably, even after such conditions had ceased to be general; and in this way the surface materials would become richer than the interior. For instance, the extruded mass of the Deccan basalt would fill a sphere 36 miles in radius. Imagine such a sphere located originally somewhere deep beneath the surface of the earth surrounded by mate- rials of like density. The ultimate excess of temperature, due to its uranium, attained at the central parts would amount to about 1,000° C., or such lesser temperature as convective effects within the mass would permit. This might take some thirty million years to come about, but before so great an excess of temperature was reached the force of buoyancy developed in virtue of its thermal expansion must inevitably bring the entire mass to the surface. This reasoning would, at any rate, apply to material situated at a considerable distance in- ward, and may possibly be connected with vulcanicity and other crustal disturbances observed at the surface.* The other view, that the addition of uranium to the earth was mainly an event subsequent to its formation in bulk, so that radio-active substances were added from without and, possibly, from a solar or cosmic source, has not the same & priori probability in its favor.? I have in this part of my address briefly to place before you an account of my experiments on the amounts of radium distributed in surface materials. Here, indeed, direct knowledge is not attainable; but this knowledge takes us but a very few miles inward toward the center of the earth. The igneous rocks. The basalt of the Deccan, to which I have referred, known to cover some 200,000 square miles to a depth of from 4,000 to 6,000 feet or more, appears to be radio-active throughout. 10° cubic miles. On a specific gravity of 2.6 my estimate in tons gives nearly the same result—84 10° cubic miles. Now, about one-third part of this parent rock goes into solution when breaking up into a detrital sediment. The limestones upon the land are part of what was once so brought into solution. Having made deduction of these former marine deposits (and [ here avail my- self of Van Hise’s and Clarke’s estimates of the total amount of the sedimentaries and the fraction of these which are calcareous) ,? and allowing for the quantity remaining in solution in the ocean, the result leaves us with the approximation of 20,000,000 cubic miles of matter once in solution and now for the greater part existing as precipitated ¢Trans. Royal Dublin Soc., Vol. VII, ser. 2, p. 23 et seq. 6 Tbid., p. 46. ¢ The Data of Geochemistry, by F. W. Clarke, p. 29. 4 Tbid., p. 31. 364 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. or abstracted deposits at the bottom of the ocean. We are to dis- tribute this quantity over its floor. If the rate of collection had been uniform in every part of the ocean throughout geological time a depth of about one-seventh of a mile (240 meters) of deposit would cover the ocean bed. While I believe we can place considerable reliance on this approxi- mation, we are less sure when we attempt an estimate of its mean radio-activity. If we assume for it an average radio-activity similar to that of Globigerina ooze, we find that the quantity of radium involved must be considerably over a million tons. Apart from the value which such estimates possess as presenting us with a perspective view of the great phenomena we are dealing with, it will now be seen that it supports the finding of the experiments on sedimentary rocks and leads us to anticipate a real difference in the radio-activity of the two classes of material. The sedimentary rocks. The radium content of those of detrital character is indicated in the following sandstones, slates, and shales: SS] OIG SH Sih aXe ISinonaVERE Crea iu (CIID) oe a a ee 4, 4 Siatesm (Cama ri arise 1D eso rnd ray) pee ee 4.7 Vir eleatre@ rr PATINA, OTN aa ae ee eee DLE Sms ae eo ate ese Oa By Some of the above are from deep borings in Carboniferous rocks (the Balfour and Burnlip bores) ,“ and from their nature, where not actually of fresh-water origin, can owe little to oceanic radio-activity. Many of the following belong to the class of precipitates, and there- fore owe their uranium wholly or in part to oceanic source: Marsiuprtes chalks. ates eee tee ee he ee eee 4,2 GreSMISAM CS COT C= Eee Eee Ay ek ee ae 4.9 Greenr sand (dred ged))\\24= "esa a eee eee 4.5 Limestones and dolomites [Trenton, Carboniferous, Zechstein, Juiass “Solemboten: (0) s] |e eee ee eee eee 4.1 LRG HOLE) pene 8h 74] ORS Nd ese ma Las eI a oO Ng 6.9 (Oforenik igoyelie, JO uaeriNML looney (OL ee als Trias-Jura sediments, Simplon: Seventeen rocks of various CINTA CEST ea a ah a Se oe ee ee 6.9 Mesozoic sediments, St. Gothard: Nineteen rocks of various CHEAT C UCT Sipe ne ek eee ee ee ee 4,2 The general mean on 62 rocks is 4.7. Making some allowance for uncertainties in dealing with the Simplon rocks, I think the experiment may be taken as pointing to the result: “Wor these rocks, and for much other valuable material, I have to thank Mr. D. Tate, of the Scottish Geological Survey. + Wor these I have to thank the trustees of the British Museum and Mr. A. S. Woodward, F. R. 8. URANIUM AND GEOLOGY—JOLY. 365 Igneous rocks from 5 to 6. Sedimentary rocks from 4 to 5. If our estimate of oceanic radium be applied to the account of the sedimentary rocks in a manner which will be understeod from what I have already endeavored to convey, there will be found to exist a fair degree of harmony between the great quantities which we have found to be in the sediments of the ocean and the impoverishment of the sediments which the experiments appear to indicate. In all these results fresh and unweathered material has been used. The sand of the Arabian desert gave me but 0.4. Similarly low re- sults have been found by others for soils and such materials. These are not to be included when we seek the radio-activity of the rocks. As regards generally my experiments on the radium-content of the rocks, I can not say with confidence that there is anything to indicate a definite falling off in radio-activity in the more deeply seated materials T have dealt with. The central St. Gothard and certain parts of the Deccan have given results in favor of such a decrease. On the other hand, as will be seen later, the granite at the north end of the St. Gothard and the primitive gneiss of the Simplon show no diminution. According to the view I have put forward above as to the origin of the surface richness in radium, it is, I think, to be ex- pected that while the richest materials would probably rise most nearly to the surface there might be considerable variability in the radio-activity of the deeper parts of the upper crust. URANIUM AND THE INTERNAL HEAT OF THE EARTH. While forced to deny of the earth’s interior any such richness in radium as prevails near the surface, the inference that uranium exists yet in small quantities far down in the materials of the globe is highly probable. This view is supported by the presence of radium in meteoric substances and by its very probable presence in the sun— that greatest of meteorites. True, the radio-thermal theory can not be supposed to account for any great part of solar heat unless we are prepared to believe that a very large percentage of uranium can be present in the sun, and yet yield but feeble spectroscopic evidence of its existence. Taken all together, the case stands thus as regards the earth: We are assured of radium as a widely distributed surface material, and to such depths as we can penetrate. By inference from the presence of radium in meteoric substances and its very probable presence in the sun, from which the whole of terrestrial stuff probably originated, as well as by the inherent likelihood that every element at the surface is in some measure distributed throughout the entire mass, we arrive at the conclusion that radium is indeed a universal ter- restrial constituent. 366 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. The dependent question then confronts us: Are we living on a world heated throughout by radio-thermal actions? This question— one of the most interesting which has originated in the discovery that internal atomic changes may prove a source of heat—can only be an- swered (if it can be answered) by the facts of geological science. I will not stop to discuss the evidence for and against a highly heated interior of the earth. I assume this heated interior the obvious and natural interpretation of a large class of geological phenomena, and pass on to consider certain limitations to our knowledge which have to be recognized before we are in a position to enter on the some- what treacherous ground of hypotheses. In the first place, we appear debarred from assuming that the sur- face and central interior of the earth are in thermal connection, for it seems certain that, since the remote period when (probable) con- vective effects became arrested by reason of increasing viscosity, the thermal relations of the surface and interior have become dependent solely on conductivity. From this it follows if the state of matter in the interior is such as Lord Kelvin assumed—that is, that the con- ductivity and specific heat may be inferred from the qualities of the surface materials—we must remain in thermal isolation from the great bulk of the interior for hundreds of millions of years, and perhaps even for more than a thousand million of years. Assuming a dif- fusivity similar to that of surface rocks, and starting with a tem- perature of 7000° F., Kelvin found that after one thousand million years of cooling there would be no sensible change at a depth from the surface greater than 568 miles. In short, even if this great period— far beyond our estimates of geological time—has elapsed since the consistentior status, the cooling surface has as yet borrowed heat from only half the bulk of the earth. It is possible, on the other hand, that the conductivity increases inward, as Professor Perry has contended; and if the central parts are more largely metallic this increase may be considerable. But we find ourselves here in the regions of the unknown. With this limitation to our knowledge, the province of geothermal speculation is a somewhat disheartening one. Thus if with Ruther- ford, who first gave us a quantitative estimate of the kind, we say that such and such a quantity of radium per gram of the earth’s mass would serve to account for the 2.6 & 10° calories, which, according to the surface gradients, the earth is losing per annum, we can not be taken as advancing a theory of radio-active heating, but only a sig- nificant quantitative estimate. For, in fact, the heat emitted by radium in the interior may never have reached the surface since the convective conditions came to an end. And here, depending upon the physical limitations to our knowl- edge of the earth’s interior. a possibility has to be faced. That URANIUM AND GEOLOGY—J OLY. 367 uranium is entirely absent from the interior is, as I have said, in the highest degree unlikely. If it is present, then the central parts of the earth are rising in temperature. This view, that the central interior is rising in temperature, is difficult to dispose of, although we can adduce the evidence of certain surface phenomena to show that the rise in temperature during geological time must be small or its effects in some manner kept under control. In a word, whether we assume that the whole heat loss of the earth is now being made good by radio-active heating or not, we find, on any probable value of the conductivity, a central core almost protected from loss by the immense mass of heated material interposed between it and the surface, and within this core very probably a continuous source of heat. It is hard to set aside any of the premises of this argument.? We naturally ask, Whither does the conclusion lead us? We can take comfort in a possible innocuous outcome. The uranium itself, however slowly its energy is given up, is not everlasting. The decay of the parent substance is continually reducing the amount of heat which each year may be added to the earth’s central materials. And the result may be that the accumulated heat will ultimately pass out at the surface by conductivity, during remote future times, and no physical disturbance result. The second limitation to our hypotheses arises from this trans- formation and gradual disappearance of the uranium. And this limitation seems as destructive of definite geothermal theories as the first. To understand its significance requires a little consideration. The fraction of uranium decaying each year is vanishingly small, about the ten thousand-millionth part; but if the temperature of the earth is maintained by uranium and consequently its decay involves the fall in temperature of the whole earth, the quantity of heat escap- ing at the surface attendant on the minute decrement would be enor- mous. An analogy may help to make this clear. Consider the familiar case of a boiler maintained at a particular temperature by a furnace within. Let the combustion diminish and the furnace tem- perature fall a little. The whole mass of the boiler and its contents follow the downward movement of temperature, heat of capacity escaping at the surface. An observer, only noting the outflow of radiated heat and unable to observe the minute drop of temperature, would probably ascribe to the continued action of the furnace, heat which, although derived from it in the past, should no longer be regarded as indicating the heating value of the combustion. Magnify the boiler to terrestrial dimensions; the minutest fall in temperature of the entire mass involves immense quantities of heat passing out at @Prof. H. A. Wilson has made a suggestive estimate of the thermal effects of radium inclosed in the central parts of the earth. (Nature, Feb. 20, 1908.) 368 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the surface, which no longer indicate the sustaining radio-thermal actions within. It is easy to see the nature of the difficulties in which we thus become involved. In fact, the heat escaping from the earth is not a measure of the radium in the earth, but necessarily includes, and for a great part may possibly be referred to, the falling temperature, which the decay of the uranium involves. If we take d (the fraction of uranium transforming each year) as approximately 10- and assume for the general mass of the earth a temperature of 1,500°, a specific heat of 0.2, and, taking 6 X 10° as its mass in grams, we have, on multiplying these values together, a loss in calories per annum of 1.8 X 10°. This by hypothesis escapes at the surface. But the surface loss, as based on earth gradients of temperature, is but 2.6 < 10°° calories. We are left with 0.8 & 10?° calories as a measure of the radium present. On this allowance our theories, in whatever form, must be shaped. Nor does it appear as if relief from this restriction can be obtained in any other way than by denying to the interior parts of the earth the requisite high thermal conductivity. Taking refuge in this, we are, however, at ence confronted with the possibility of internal stores of radium of which we know nothing, save that they can not, probably, be very great in amount. In short, I believe it will be admitted on full examination of this question that, while we very probably are isolated thermally from a considerable part of the earth’s interior, the decay of the uranium must introduce a large subtractive correction upon our estimates of the limiting amounts of radium which might be present in the earth. But, finally, is there in all these difficulties sufficient to lead us to reject the view that the present loss of earth heat may be nearly or quite supplied by radium, and the future cooling of the earth con- trolled mainly by decay of the uranium? I do not think there are any good grounds for rejecting this view. Observe, it is the condition toward which every planetary body and every solar body containing stores of uranium must tend; and apparently must attain when the rate of loss of initial stores of heat, diminishing as the body grows colder, finally arrives at equilibrium with the radio-thermal supplies. This final state appears inevitable in every case unless the radio- active materials are so subordinate that they entirely perish before the original store of heat is exhausted. Now, judging from the surface richness in radium of the earth and the present loss of terrestrial heat, it does not seem reasonable to assign a subordinate influence to radio-thermal actions; and it appears not improbable that the earth has attained, or nearly attained, this final stage of cooling. How, then, may we suppose the existing thermal state maintained ? A uniformly radio-active surface layer possessing a basal temperature URANIUM AND GEOLOGY—JOLY. 369 in accordance with the requirements of geology is, I believe, not realizable on any probable estimate of the allowable radium, or on any concentration of it which my own experiments on igneous rocks would justify. But we may take refuge in a less definite statement, and assume a distribution by means of which the existing thermal state of the crust may be maintained. Schardt, loc. cit. URANIUM AND GEOLOGY—ZJOLY. ate general mean is (on my experiments) 7.1 million millionths of a gram per gram. This mean is well distributed, as follows: JULASsICHanGd Triassicvaltered, Sediments! 2242 — 2 eee 6.4 Crystalline schists, partly Jurassic and Triassic, partly Archean_ 7.3 Monte Leone gneiss and primitive gneiss_——---—______________ 6.3 Schistose eneiss’ (a -fold) from: beneath) =—— ===. 2 6.5 BATU GGL OTE Oe STU CLS Se eee ene ee 2 lee 6.8 The divisional arrangement is Professor Schardt’s. Forty-nine typical rocks are used in obtaining these results, and the experiments have been in many cases repeated on duplicate specimens. Including some very exceptional results, the means would rise to 9.1 x 10- grams per gram. Of the St. Gothard rocks I have examined 51 specimens, selected to be, as far as attainable, representative.* Of these, 21 are from the central region, and their mean radium content is just 3.3. The portion of the tunnel from which these rocks come is closely coincident with Stapfi’s thermal subdivision of regions of low temperature.” This portion of the mountain offers the most definite conditions for comparison with the Simplon results. The region south of this is affected by water circulation; the regions to the north are affected by the high temperature of the granite. We see, then, that the most definite data at our disposal in compar- ing the conditions as regards temperature and radio-thermal actions in the two tunnels appear to show that the steeper gradient is asso- ciated with the greater radium content. It is possible to arrive at an estimate of the downward extension of the two rock masses (assumed to maintain to the same depth their observed radio-activity), which would account for the difference in gradient. In making this estimate, we do not assume that the entire heat flow indicated by the gradients is due to radium, but that the difference in radium content is responsible for the difference of heat flow. If some of the heat is conducted from an interior source (of whatever origin), we assume that this is alike in both cases. We also assume the conductivities alike. Calculating on this basis, the depth required to establish on the -adium measurements the observed difference in gradients of the Cen- tral St. Gothard and of the Simplon, we find the depth to be about 7 kilometers on the low mean of the Simplon rocks and 5 kilometers on the high mean. There is, as I have already said, nothing improbable in such a downward extension of primitive rocks having the radio- @J would like to express here my acknowledgments to the trustees of the British Museum for granting me permission to use chips of the rocks in their possession, and especially to Mr. Prior for his valuable assistance in selecting the specimens. ’ Trans. North of England Min. and Mech. Eng., Vol. XX XIII, p. 25. 374 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. activities observed; but as a different distribution of radium may, of course, obtain below our point of observation, the result can only claim to be suggestive. Turning specially to the St. Gothard, we find that a temperature problem of much interest arises from the facts recorded. The north end of the tunnel for a distance of 2 kilometers traverses the granite of the Finsteraarhorn massif. It then enters the infolded syncline of the Usernmulde and traverses altered sediments of Trias-Jura age for a distance of about 2 kilometers. After this it enters the crushed and metamorphosed rocks of the St. Gothard massif, and remains in these rocks for 74 kilometers. The last section is run through the Tessin- mulde for 3 kilometers. These rocks are highly altered Mesozoic sediments. I have already quoted Stapff’s observations as to the variations of gradient in the northern, central, and southern parts of the tunnel. He writes: “ They (the isotherms) show irregularities on the south side, which clearly depends on cold springs; they bend down rapidly, and then run smoothly inclined beneath the water-filled section of the mountain. Other local irregularities can be explained by the decom- position of the rock; but there is no obvious explanation of the rapid increase in the granite rocks at the northern end of the tunnel (2,000 meters), and it is probably to be attributed to the influence of differ- ent thermal qualities of the rock on the coefficient of increase. For the rest these 2,000 meters of granite belong to the massif of the Finste- raarhorn, and, geologically speaking, they do not share in the com- position of the St. Gothard. Perhaps these two massifs belong to different geological periods (as supposed for geological reasons long ago). What wonder, then, if one of them be cooler than the other.” (Loe. cit., p. 30.) Commenting on the explanation here offered by Stapff, Prestwich ¢ states his preference for the view that the excess of temperature in the granite is due to mechanical actions to which the granite was exposed during the upheaval of this region of the Alps. The accompanying diagram shows the distribution of temperature as given by Stapff, and the distribution of radium as found from typical specimens of the rocks. There is a correspondence between the two which is obvious, and when it is remembered that the increase in radio-activity shown at the south end would have been, according to Stapff, masked by water circulation, the correspondence becomes the more striking. The small radium values in the central parts of the tunnel are remarkable. The rocks of the Central St. Gothard massif are apparently exceptionally poor in radium. At the north end the excess of radi a is almost confined to the granite, the .uck to which Stapff ase ed the exceptional tempera- @ Proc. Roy. Soc, Vi. MI, p: 44: Smithsonian PLATE 1. ps increase of temperature per metre :| scale 0°Q05° to unity. 0 12.000 14.000 metres Smithsonian Report, 1908.—Joly, 0 £000. 4000 6000 8000 70000 o PLATE 1. B 2000 4000 6000 8,000 10000 12000 COMPARATIVE RADIUM AND TEMPERATURE MEASUREMENTS. a on ee: cera | cee a J , i C ee . J ; win Whi ty sare cca ra Sc “4 : yj ‘- eos a BONS fey me ge | Soy Aiaptieat eget a ee jo “haere th, : s a: ? ae ‘ «y ) ae ime it Rat ai i n ny ee : Sis Ay Peal t an . 7 if e a ; , yy i‘ eg = mi Ss y - | i URANIUM AND GEOLOGY—JOLY. 375 tures. The radium of the Usernmulde is probably not very important, seeing that these sediments can not extend far downward. The prin- cipal local source of heat appears located more especially beneath the synclinal fold, for Stapff’s table (loc. cit., p. 31) of the gradients beneath the plain of Andermatt shows a rising gradient to a point about 2,500 meters from the north entrance of the tunnel. It is observable that the radio-activity of the granite increases as it ap- proaches the Usernmulde and attains its maximum (14.1) where it dips beneath the syncline. The means of radium content in the several geological sections into which the course of the tunnel is divisible are as follows: GraMIce ROEM Ste rea ar Oras eee ee ye at RUG STEN Ua he ee a ae he a ie 4.9 St Gothardtmassite — v8 sa Sa ta 3.9 ADESTS HANGS UID eye btaen Sk RAI AR RE ee ee ee ee eras 3. 4 The central section, however, if considered without reference to geological demarcations, would, as already observed, come out as barely 3.3. And this is the value of the radio-activity most nearly applicable to Stapff’s thermal subdivision of the region of low tem- perature. If we accept the higher readings obtained in the granite as indica- tive of the radio-active state of this rock beneath the Usernmulde, a satisfactory explanation of the difference of heat flow from the cen- tral and northern parts of the tunnel is obtained. Using the differ- ence of gradient as basis of calculation, as before, we find that a downward extension of about 6,000 meters would, if the outflow took place in an approximately vertical direction, account for the facts observed by Stapff. This depth is in agreement with the result as to the downward extension of the St. Gothard rocks as derived from the comparison with the Simplon rocks. We are by no means in a position to found dogmatic conclusions on such results; they can only be regarded as encouragement to pursue the matter further. The coincidence must be remarkable, however, which thus similarly localizes radium and temperature in roughly proportional amounts, and permits us, without undue assumptions, to explain such remarkable differences of gradient. There is much work to be done in this direction, for well-known cases exist where excep- tional gradients in deep borings have been encountered—exceptional both as regards excess and deficiency. RADIO-ACTIVE DEPOSITS AND THE INSTABILITY OF THE CRUST. At the meeting of the British association held last year at Leicester I read a note on the thermal effects which might be expected to arise at the base of a sedimentary accumulation of great thickness due to the contained radium. 88292—sm 1908 25 376 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. The history of mountain building has repeated itself many times; ages of sedimentation, with attendant sinking of the crust in the area of deposition, then upheaval, folding up of the great beds of sedi- ment, and even their overthrusting for many miles. So that the mountain ranges of the world are not constituted from materials rising from below, save in so far as these may form a sustaining core, but of the slowly accumulating deposits of the ages preceding the upheaval. The thickness of collected sediments involved in these great events is enormous, and although uncertainty often attends the estimation of the aggregate depths of sedimentation, yet when we consider that unconformities between the deposits of succeeding eras represent the removal of vast masses of sediment to fresh areas of deposition, and often in such a way as to lead to an underestimate of the thickness of deposit, the observations of the geologist may well indicate the minor and not the major limit. Witness the mighty layers of the Huronian, Animikean, and Keweenawan ages, where deposits meas- ured in miles of thickness are succeeded by unrecorded intervals of time, in which we know with certainty that the tireless forces of denudation labored to undo their former work. Each era represents a slow and measured pulse in the earth’s crust, as if the overloading and sinking of the surface materials induced the very conditions required for their reelevation. Such events, even in times when the crust was thinner and more readily disturbed than it is now, must have taken vast periods of time. The unconformity may represent as long a period as that of accumulation. In these Proterozoic areas of America, as elsewhere on the globe and throughout the whole of geological history, there has been a succession in time of foldings of the crust always so located as to uplift the areas of sedimentation, these upheavals being sundered by long intervals, during which the site of sedimentation was transferred and preparation made for an- other era of disturbance. However long deferred, there seems to be only the one and inevitable ending, inducing a rhythmic and monoto- nous repetition surely indicative of some cause of instability attend- ing the events of deposition. The facts have been impressively stated by Dana: A mountain range of the common type, like that to which the Appalachians belong, is made out of the sedimentary formations of a long-preceding era; beds that were laid down conformably and in succession until they had reached the needed thickness; beds spreading over a region tens of thousands of square miles in area. The region over which sedimentary formations were in progress in order to make, finally, the Appalachian Range reached from New York to Ala- bama and had a breadth of 100 to 200 miles, and the pile of horizontal beds along the middle was 40,000 feet in depth. The pile for the Wahsatch Moun- tains was 60,000 feet thick, according to King. The beds for the Appalachians were not laid down in a deep ocean, but in shallow waters, where a gradual subsidence was in progress; and they at last, when ready for the genesis, lay URANIUM AND GEOLOGY—JOLY. Ser in a trough 40,000 feet deep, filling the trough to the brim. It thus appears that epochs of mountain making have occurred only after long intervals of quiet in the history of a continent. The generally observed fact that the deposition of sediments in some manner involves their ultimate upheaval has at various times led to explanations being offered. I think I am safe in saying that although the primary factor, the compressive stress in a crust which has ceased to fit the shrinking world within it, has probably been correctly inferred, no satisfactory explanation of the connection be- tween sedimentation and upheaval has been advanced. The mere shifting upward of the isogeotherms into the deposits, advanced as a source of local loss of rigidity by Babbage and Herschel, need not involve any such loss so long as the original distance of the isogeo- therms from the surface is preserved. We see in every case that only after great thicknesses of sediments have accumulated is the upheaval brought about. This is a feature which must enter as an essential condition into whatever explanations we propose to offer. Following up the idea that the sought-for instability is referable to radio-thermal actions, we will now endeavor to form some approxi- mate estimate of the rise of temperature which will be brought about at the base of such great sedimentary accumulations as have gone toward mountain building, due to the radium distributed throughout the materials. The temperature at the base of a feebly radio-active layer, such as an accumulation of sediments, is defined in part by radio-active en- ergy, in part by its position relative to the normal isogeotherms, whether these latter are in turn due to or influenced by radio-thermal supplies or not. It is convenient and, I think, allowable to consider these two effects separately and deal with them as if they were inde- pendent, the resultant state being obtained by their summation. In dealing with the rise of temperature at the base of a radio-active layer we arrive at an expression which involves the square of the depth. This is a very important feature in the investigation, and leads to the result that for a given amount of radium diffuse dis- tribution through a great depth of deposit gives rise to a higher basal temperature than a more concentrated distribution in a shallower layer. But this will not give us the whole effect of such a deposit. An- other and an important factor has to be taken into account. We have seen that the immediate surface rocks are of such richness in radium as to preclude the idea that a similar richness can extend many miles inward. Now, it is upon this surface layer that the sediments are piled, and as they grow in thickness this original layer is depressed deeper and deeper, yielding under the load, until at length it is buried to the full 378 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. depth of the overlying deposit. This slow and measured process is attended by remarkable thermal effects. The law of the increase of temperature with the square of the depth comes in, and we have to consider the temperature effect not merely at the base of the deposited layer, but that due to the depression and covering over of the radium- rich materials upon which the sediments were laid down. The table which follows embodies an approximate statement of the thermal results of various depths of deposit supposed to collect under conditions of crustal temperature such as prevail in this present epoch of geological history: Weakening of earth’s Resulting | crust as de- rise of iso- | fined by the geotherms.| rise of the geotherm at 40 kilometers Thickness of sedimen- tary de- posit. Kilometers. | Kilometers.| Kilometers. 6 7.4 40 to 32.6 8 10.2 40 to 29.8 10 13.3 40 to 26.7 12 16.7 40 to 23.3 14 20. 4 40 to 19.6 I have deferred to the conclusion of this address an account of the steps followed in obtaining the above results. It is clearly impossible within the limited time allotted to me to make these quite clear. It must suffice here merely to explain the significance of the figures. The first column gives the depth of sedimentary deposit supposed to be laid down on the normal radio-active upper crust of a certain as- sumed thickness and radio-activity. From the rise of temperature which occurs at the base of this crust (due to the radio-activity, not only of the crust, but of the sediments) the results of the second col- umn are deduced, the gradient or slope of temperature prevailing beneath being derived from the existing surface gradients corrected for the effects of the radio-thermal layer. The third column is in- tended to exhibit the effect of this shift of the geotherms in reducing the strength of the crust. I assume that at a temperature of 800° the deep-seated materials lose rigidity under long-continued stress. The estimated depth of this geotherm is, on the assumptions, about 40 kilometers. The upward shift of this geotherm shows the loss of strength. Thus in the case of a sedimentary accumulation of 10 kilo- meters the geotherm defining the base of the rigid crust shifts up- ward by 13 kilometers, so that there is a loss of effective section to the amount of 30 per cent.* “See Appendix B to this article. URANIUM AND GEOLOGY—JOLY. 379 As regards the claims which such figures have upon our considera- tion, my assumptions as to thickness and radio-activity of the spe- cially rich surface layer are doubtless capable of considerable amend- ment. It will be found, however, that the assumed factors may be supposed to vary considerably, and yet the final results prove such as, I believe, can not be ignored. Indeed those who are in the way of making such calculations, and who enter into the question, will find that my assumptions are not specially favorable, but are, in fact, made on quite independent grounds. Again, a certain class of effects has been entirely left out of account, effects which will go toward enhancing, and in some cases greatly enhancing, the radio-thermal activity. I refer to the thickening of the crust arising from tangen- tial pressure, and, at a later stage, the piling up and overthrusting of mountain-building materials. In such cases the temperature of the deeper parts of the thickened mass must still further rise under the influence of the contained radium. These effects only take place, indeed, after yielding has commenced, but they add to the element of instability which the presence of the accumulated radio-active de- posits occasions, and doubtless increase thermal metamorphic actions in the deeper sediments and result in the refusion of rocks in the upper part of the crust.¢ The effect of accumulated sediment is thus necessarily a reduction in the thickness of that part of the upper crust which is capable of resisting a compressive stress. Over the area of sedimentation, and more especially along the deepest line of synclinal depression, the crust of the globe for a period assumes the properties belonging to an earlier age, yielding up some of the rigidity which was the slow in- heritance of secular cooling. Along this area of weakness—from its mode of formation generally much elongated in form—the stressed crust for many hundreds, perhaps thousands, of miles finds relief, and flexure takes place in the only possible direction—that is, on the whole upward. In this way the prolonged anticline bearing upward on its crest the whole mass of deposits is formed, and so are borne the moun- tain ranges in all their diversity of form and structure. We have in these effects an intervention of radium in the dynamics of the earth’s crust, which must have influenced the entire history of our globe, and which, I believe, affords a key to the instability of the crust; for after the events of mountain building are accomplished, stability is not attained, but in presence of the forces of denudation the whole sequence of events has to commence over again. Every “Prof. C. Schmidt (Basel) has recently given reasons for the view that the Mesozoic schists of the Simplon at the period of their folding were probably from 15,000 to 20,000 meters beneath the surface (He. Geol. Helvetia, Vol. IX, No. 4, p. 590). As another instance consider the compression of the Laramide range (Dawson, Bull. Geol. Soc. Amer., Vol. XII, p. 87). 380 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. fresh accession of snow to the firn, every passing cloud contributing its small addition to the torrent, assists to spread out once more on the floor of the ocean the heat-producing substance. With this rhythmic succession of events appear bound up those positive or negative move- ments of the strand which cover and uncover the continents, and have swayed the entire course of evolution of terrestrial life. Oceanic deposits. The displacements of the crust which we have been considering are now known to be by no means confined to the oceanic margins. The evidence seems conclusive that long-continued movements have been in progress over certain areas of the sea floor, attended with the for- mation of those numerous volcanic cones upon which the coral island finds foundation. Here there are plainly revealed signs of instability and yielding of the crust (although, perhaps, of minor intensity) such as are associated with the greater movements which terminate in mountain building. I think it will be found, when the facts are con- sidered, that we have here phenomena continuous with those already dealt with, and although the conditional element of a sufficient sedi- mentary accumulation must remain speculative, the evidence we pos- sess 1s in favor of its existence. One of the most interesting outstanding problems of deep-sea physiography is that of the rates of accumulation of the several sorts of deposit. In the case of the more rapidly collecting sediments there seems to be no serious reason why the matter should not be dealt with observationally. I hope it may be accomplished in our time. For my present purpose I should lke to know what may or may not be assumed in discussing the accumulation of radio-active sediments on the ocean floor. As regards the rate of collection of the noncalcareous deposits, the nearest approach to an estimate is, I think, to be obtained from the exposed oceanic deposits of Barbados. In the well-known paper of Jukes Brown and Harrison ¢ on the geology of that island, it is shown that the siliceous radiolarian earths and red clays aggregate to a thickness of about 300 feet. These materials are true oceanic deposits, devoid of terrigenous substances. They collected very probably dur- ing Phocene and, perhaps, part of Pleistocene times. Now there is evidence to lead us to date the beginning of the Pliocene as anything from one million to three million years ago. The mean of these esti- mates gives a rate of collection of 5 millimeters in a century. This sounds a very slow rate of growth, but it is too fast to be assumed for such deposits generally. More recent observations might, indeed, lead us to lengthen the period assigned to the deposition of these “Quart. Journ. Geol. Soc, Vol. XLVIII, p. 210. URANIUM AND GEOLOGY—JOLY. 881 oceanic beds; for if, following Professor Spencer,* we ascribe their deposition to Eocene times, a less definite time interval is indicated ; but the rate could hardly have been less than 3 millimeters in a cen- tury. The site of the deposit was probably favorable to rapid growth. We have already found a maximum limit to the average thickness of true oceanic sediments, and such as would obtain over the ocean floor if the rate of collection was everywhere the same and had so con- tinued during the past. If there is one thing certain, however, it is that the rates of accumulation vary enormously. The 1,200 or 1,500 feet of chalk in the British Cretaceous, collected in one relatively brief period of submergence, would alone establish this. Huxley inferred that the chalk collected at the rate of 1 inch in a year. Sollas showed that the rate was probably 1 inch in forty years. Sir John Murray has advanced evidence that in parts of the Atlantic the cables become covered with Globigerina ooze at the rate of about 10 inches in a century. Finally, then, we must take it that the fair allowance of one-seventh of a mile may be withheld in some areas and many times exceeded in others. Now, it is remarkable that all the conditions for rapid deposition seem to prevail over those volcanic areas of the Pacific from which ascend to the surface the coral islands—abundant pelagic life and comparatively shallow depths. Indeed, I may remind you that the very favorable nature of the conditions enter into the well-known theory of coral-island formation put forward by Murray. The islands arise from depths of between 1,000 and 2,000 fathoms. These areas are covered with Globigerina ooze having a radio-activity of about 7 or 8. The deeper-lying deposits around—red clay and radiolarian ooze—show radio-activities up to and over 50. From these no volcanic islands spring. These facts, however, so far from being opposed to the view that the radio-activity and crustal disturbance are connected, are in its favor. For while those rich areas testify to the supply of radio- active materials, the slow rate of growth prevailing deprives those deposits of that characteristic depth which, if I may put it so, is of more consequence than a high radio-activity. For the rise in tem- perature at the base of a deposit, as already pointed out, is propor- tional to the square of the thickness. In reality the dilution of the supphes of uranium which reach the calcareous oozes flooring the disturbed areas is a necessary condition for any effective radio- thermal actions. It might appear futile to consider the matter any closer where so little is known. But in order to give an idea of the quantities in- 4 Quart. Journ. Geol. Soc., Vol. LVIII, p. 354 et seq. 382 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. volved I may state that, if my calculations are correct, a rate of dep- osition comparable with that of the chalk prevailing for ten million years would, on assumptions similar to those already explained when discussing the subject of mountain building, occasion a rise of the deeper isogeotherms by from 20 to 30 per cent of their probable normal depth. In making these deductions as to the influence of radium in sedi- mentary deposits I have so far left out of consideration the question of the time which must elapse in order that the final temperature- rise in the sediments must be attained. The question we have to answer is: Will the rate of rise of temperature due to radium keep pace with the rate of deposition, or must a certain period elapse after the sedimentation is completed to any particular depth before the basal temperature proper to the depth is attained ? The answer appears to be, on an approximate method of solution, that for rates of deposition such as we believe to prevail in terrigenous deposits—even so great as 1 foot in a century, and up to depths of accumulation of 10 kilometers and even more—the heating waits on the sedimentation. Or, in other words, there is thermal equilibrium at every stage of growth of the deposit; and the basal temperature due to radio-active heating may at any instant be computed by the conductivity equation. For accumulations of still greater magnitude the final and maximum temperature appears to lag somewhat behind the rate of deposition. From this we may infer that the great events of geological history have primarily waited upon the rates of denudation and sedimenta- tion. The sites of the terrigenous deposits and the marginal oceanic precipitates have many times been convulsed during geological time because the rates of accumulation thereon have been rapid. The com- parative tranquillity of the ocean floor far removed from the land may be referred to the absence of the inciting cause of disturbance. If, however, favorable conditions prevail for such a period that the local accumulations attain the sufficient depth, here, too, the stability must break down and the permanency be interrupted. Upheaval of the ocean floor, owing to the laws of deep-sea sedi- mentation, should be attended with effects accelerative of deposition— a fact which may not be without influence. But although ultimately sharing the instability of the continental margins, the cycle of change is tuned to a slower periodicity. From the operation of these causes, possibly, have come and gone those continents, which many believe to have once replaced the wastes of the oceans, and which with all their wealth of life and scenic beauty have disappeared so completely that they scarce have left a wreck behind. But those forgotten worlds may be again restored. The rolled-up crust of the earth is still rich in energy borrowed from earlier times, and the slow but URANIUM AND GEOLOGY—JOLY. 383 mighty influences of denudation and deposition are forever at work. And so, perchance, in some remote age the vanished Gondwana Land, the lost Atlantis, may once again arise, the seeds of resurrection even now being sown upon their graves from the endless harvests of pelagic life. APPENDIX A, Convective movement of wranium to the earth’s surface (p. 359). The estimate of temperature given assumes (1) that the mass of igneous material is spherical, and (2) that its surface is kept at constant temperature, heat escaping freely. The first assumption is in favor of increasing the esti- mate of temperature, and probably would not generally be true, especially of a mass moving upward. The second assumption tends to give a lower estimate of temperature, and is certainly inaccurate, as the surrounding materials are nonconducting and must favor the accumulation of radio-active heat. On assumptions (1) and (2) and on Barus’s results for the thermal expansion of diabase between 1,100° and 1,500°,¢ and results of my own on basalt,? which are in approximate agreement, and assuming the mean excess of temperature to be 500° and the surrounding material to be at a fluid temperature, the force of buoyancy comes out at over 60 dynes per cubic centimeter of the spherical mass. This is an underestimate. If we may assume that the Deccan Trap is indeed an instance of such an overheated mass escaping at the surface, and that similar radio-active masses rising up from beneath at various times in the past may have affected the crust, we have at our disposal a local source of energy of plutonic origin which may account for much. APPENDIX B. Sedimentation and rise of geotherms (p. 878). The depth of the upper radio-active layer is, of course, unknown. We pos- sess, however, the means of arriving at some idea of what it must be. The quantitative thermal conditions impose a major limit to its average thickness, and the indications of injected rocks suggest a minor limit. If 2.6 X 10” calories is the heat output of the whole earth per annum, and if we assign only one-fifth of this amount to cooling due to decay of the uranium, then, on the assumption that the earth is no longer losing any part of its original store of heat, we have about 2 X 10” representing radium heating. From this the allowance of terrestrial radium per square centimeter inward is 2.8 X 10-5 grams. This would give a major limit. But it is probable that a large part of this radium is located in more deeply seated parts of the earth. If we take 10- as contained in the normal radio-active surface layer, and assume (what according to my experiments should not be far from the truth) that the aver- age radio-activity is 8, we arrive at a thickness of 12 kilometers. Some such mean value is necessitated by the evidence we derive from the radio-activity of igneous rocks. These rocks must in many cases be derived @ Phil. Mag., Vol; XXOXV, p. 173. bTrans. Roy. Dublin Soc., Vol. VI, p. 298. 384 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. from considerable depths. Such outflows as the Deccan may indicate local suberustal conditions; so also may the eruptions of certain volcanic areas. But those extrusions which have attended mountain building, more especially its closing phases, appear to indicate general conditions, and involve the ex- istence of such radio-active materials at considerable depths. If we assume a thickness for the radio-active part of the crust much less than the 12 kilometers, difficulties are met with on this line of reasoning.@ Proceeding now to the derivation of the results given in the table, p. 16. The equation k6=qhe(D—3) (where 6 is the temperature at the depth v, D being the total depth of the radio-active layer, g the radium per cu. cm. in grams, h the heat output of one gram of radium per second, k the thermal conductivity) is easily derived by considering the conditions of thermal flow in the layer, supposed to lose heat only at the surface.? The aggregate depths of radio-active material in the several cases of sedimen- tary deposit assumed in my address amount to 18, 20, 22, 24, and 26 kilometers. I assume the mean radio-activity to be 3.5, and the average conductivity to be 4x 10°. From this the basal temperatures are found, as due to radio-thermal actions. These temperatures are to be augmented by the temperatures proper to the several depths, which depend upon the conducted interior heat. To estimate these we require to apportion the observed average surface gradient (taken as 32 meters per degree) between radio-active effects in the upper layer and the flow of heat from within. The radio-thermal gradient comes out at about 75 meters; the inner gradient is accordingly 56 meters. Hence the total tempera- ture at the base of each radio-active mass is obtained. But the geotherms proper to the several depths, 18, 20, etc., kilometers, under conditions prevailing elsewhere in the crust, are easily found from the value of 6 for the normal layer (82° C.), and adding the temperature due to interior heat. From the difference of the temperatures we finally find the rise of the geotherms. As conveyed in my address, I have found on several different values of the thickness and radio-active properties of 1 e surface layer, results in every case showing large values for the rise of the geotherms. The data assumed above are by no means the most favorable. « See p. 379, ante, and footnote as bearing on the possible displacement of the geotherms. » See Strutt, Proc. Roy. Soc., Vol. LX XVII, p. 482. AN OUTLINE REVIEW OF THE GEOLOGY OF PERU. [With 5 plates.] By GerorcEe I. ADAMs. INTRODUCTION. More than a century has elapsed since Humboldt beheld the grand Cordilleras in northern Peru, and more than three-quarters of a cen- tury has passed since d’Orbigny studied the section of the Andes in the southern part of the country. Since then many scientists have been attracted to the region and have contributed to the knowledge of its geology. Their writings are scattered in numerous publications in English, German, French, and Spanish, and no summary of this information has been made. The writer in attempting to learn what is known concerning the subject has gleaned the material which con- stitutes this paper. The arrangement and presentation of it in the form of an outline review has been undertaken with the hope that it may serve as an introduction to the broader problems with which later geologists may have to deal. The author’s contributions to the geology of Peru have been pub- lished in bulletins of the Corps of Engineers of Mines of Peru, and relate principally to the distribution of the Tertiary formations of the coast of which he made a reconnaissance. Later, while engaged in private work, he traveled in the Titicacan region of Peru and Bolivia, crossed the Cordilleras, and entered the forest region of southern Peru, and also saw something of the Cordilleras of the central part of the country. It is not his intention, however, to at- tempt to incorporate his observations during these journeys to any great extent in this paper, but rather to use them as an aid to the in- terpretation of the work of others. The geologic relations of the rocks of Peru have thus far been ex- plained by written descriptions accompanied in some cases by sections, but there are practically no geologic maps. It is to be hoped that the mapping of some type localities may soon be undertaken and that the columnar sections for the various regions may be established and the paleontologic studies correlated with them. The time has arrived when simple geologic reconnaissance can not be expected to yield satisfactory results, 385 386 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Accompanying this paper will be found a bibliography of the more important literature, and in the footnotes some additional refer- ences are given. Nearly all of the literature of the subject has been consulted in the preparation of this review, but it has not been deemed advisable to publish a more complete bibliography, since some of the articles with elaborate titles have in reality little value and, being quite inaccessible to the general student, can hardly hope to hold a place with the more important contributions, which embody the essential truths with fewer errors. Puysicau AND Curmatic REGIons. THE THREE REGIONS OF PERU. The dominant physical feature of Peru is the lofty range of the Andes which lies near the Pacific Ocean and forms a barrier between the narrow strip of desert coast and the extensive wooded plains of the Amazon. Accordingly, the country is commonly recognized as presenting three naturally defined regions which differ in their phys- ical features and climate; namely, the coast, the sierra, and the forest, or “montafia,” as it is called in Peru. The use of these terms orig- inated with the inhabitants, and they have to a considerable extent found their way into scientific literature. The name “ montafia ” is apt to be misleading, especially to a foreigner, since it suggests moun- tains. “ Selva,” meaning forest, would seem to be more appropriate. If terms are selected which may be broadly used in considering the South American continent one may appropriately speak of the Pacific coastal region, the Andes Mountain region, and the Amazon plains region. These terms have physiographic signification and should come into use in scientific writings. The extension of these regions may be learned from the accompanying map (pl. 1). PACIFIC COASTAL REGION. Definition. The distinction between the coast and the sierra as commonly made is one of climate and is indicated by differences in agriculture. In the coast the agricultural products are those of the tropical and sub- tropical climates, while those of the sierra are such as are found in the temperate zones. The transition from one region to the other is abrupt because of the steep declivity of the Pacific slope of the Andes. With the exception of the part of Peru adjacent to the Gulf of Guayaquil, the division between the coast and the sierra corresponds with the approximate western limit of general annual rainfall on GEOLOGY OF PERU—ADAMS. 387 the Pacific slope of the Andes. This is largely determined by eleva- tion and temperature, and is indicated as one travels from town to town by the character of the roofs of the houses of the natives. The writer in drawing the line upon his published maps? used this as a basis for his observations and inquiries in order to obtain reliable information. Near the Gulf of Guayaquil, where the zone of rainfall is deflected to the westward from the slope of the Andes over the coastal plains and to the Pacific Ocean, the division between coast and sierra would be made by continuing the trend of the line into Ecuador, taking into consideration the character of the agriculture, which varies with the temperature dependent on elevation. For Peru the distine- tion based on climate holds fairly well, but in Ecuador it is less satis- factory, since under the Equator and in a region of rainfall the zones of vegetation and agriculture do not correspond with the topographic distinction also implied. Divisions of the coastal region. The coastal region of Peru may be divided into plains areas and mountainous areas. The plains, according to their geographic posi- tions in the country, may be called the “ northern,” “ south central,” and “southern.” Between the northern and south central plains, and likewise between the south central and southern, the coast is moun- tainous. The northern and south central plains extend inland from the shore of the Pacific, but the southern plains are separated from the sea by a coast range of hills. The mountainous divisions of the coast are diversified by the stream valleys and their tributary dry valleys and present a very broken topography. The southern one of these two mountainous areas, considered as a mass, rises abruptly from the sea and presents many aspects of a dissected plateau. The northern area is characterized by a more broken coast line and the mountains rise in a ragged, irregular way toward the sierra. It would seem to be an open question as to whether these mountainous areas should be classed with the coast or the Andes region. Along the inner border of the plains are the “ foothills ” rising to the sierra, and at a corresponding distance inland in the mountainous divisions of the coast there is a transition zone known as the “ valley heads of the coast ” (cabezeras de los valles), where the valley floors become narrow and stony, so that the agriculture of the coast is impossible, and the mountains rise on either side into the temperature and cli- mate of the sierra. 4 Maps reproduced in this report as Plates Nos. 2, 3, 4, and 5, 388 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. THE ANDES MOUNTAIN REGION. The distinction between the coast and the sierra has already been explained. [The division line between the sierra and the Amazon region would seem to be simple enough if it is based on the presence of the forest, as is implied when the word “ montafia” is used. (See p- 386 above.) | The tree line, however, especially in the northern part of Peru, according to the data which the writer has obtained from reading, rises well up onto the flanks of the Andes, and indeed covers some of the mountains which may be appropriately classed with the Andes region. It may also be noted that the limits of the forest have never been accurately shown on any map. It would seem DECEMBER JANUARY FEBRUARY AUGUST SEPTEMBER OCTOBER ' ' ' ‘ L | es Pa ee, ieee mal oe \ 1 Se H 1 1 1 I iT | i] Fic. 1.—Variations of temperature at Lima. proper to restrict the Amazon region to the plains lying to the east of the mountains in order to make the division a physiographic one. It is not possible to draw this line from information now available. In the accompanying sketch map of the Cordillera of the Andes the hachuring of the mountainous area has been done as accurately as possible from available data, but it will be remembered that Rai- mondi’s map of Peru, which is the most detailed, is known to be de- fective, and to a considerable extent the hachuring on it is imaginary. Divisions of the Andes region. The main features of the Andes are the Cordilleras proper, which will be described in some detail later. Corresponding with them GEOLOGY OF PERU—ADAMS. 389 are the great inter-Andean valleys, which are occupied by streams tributary to the Amazon and which are shown in a general way on the hachured map, and which may be named from the rivers occupying them. On the Pacific slope there is one inter-Andean val- ley between the Cordillera Negra and Blanca known as the “ Valley of Huaylas” (Callejon de Huaylas). In addition should be noted the Titicaca Lake basin. If one attempts to go further into the classification of the physiographic features, there are many short ranges of mountains or spurs from the main Cordillera, some of which are named on Raimondi’s map, and also high plains and table- lands (frequently called “ punas”’) which are worthy of distinction. JANUARY FEBRUARY AUGUST SEPTEMBE! OCTOBER NOVEMBER DECEMBER ' 1 ' ' ' + 1 ' 1 ' ' ' ' ' ' as ' ! ! ' ' ' ' = adhiee OT pL eee Fig. 2.—Variations of temperature at Ica. Rainfall in the Andes. The rain which falls in the Andes region is brought as vapor from the Atlantic and most of it is precipitated in the Amazon region or on the eastern flank of the first Cordillera which it encounters. Dur- ing the summer season the clouds rise higher and pass farther to the west, distributing their moisture on the Cordilleras and a part of it crosses the Continental Divide or the western Cordillera. It is gen- erally believed that the rainfall on the Pacific slope, the limit of which has already been discussed, comes over the Cordilleras, except in the region of the Gulf of Guayaquil. This is in accordance with the observations of many travelers and the general theory of the 390 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. influence of the trade winds. Clouds are not seen passing to the Cordillera from the Pacific. The mists of the coast which drift in- land from the Pacific form at the season when the sky in the Cor- dillera is clear and their movements are with the land and sea breezes. Systematic observations of the rainfall in the Andes region have been carried on at only one locality, namely, Cailloma, which is situated north of Arequipa and just to the east of the Continental Divide. From the published data the writer has constructed 1897 1898 1899 1900 1901 1902 the accompanying dia- grams (figs. 3 and 4) which show the annual and monthly variations of the rainfall. The Cordilleras of the Andes. DESCRIPTION BY HUMBOLDT, 1802. Although Humboldt did not have Peru as an object of special study and did not visit the country excepting to see the coast at Pisco and Lima and to travel in the northern highlands be- tween Cajamarca and the Maranon,’ he neverthe- less gave a graphic and to a large extent a correct description of the chain of the Andes, availing himself of data furnished by others. He says, in sub- stance, that in southern Peru there are two branches of the Andes which include between them the Titicaca basin. To the north of the Titicaca basin there is a knot which includes Vilcanota, Carabaya, Abancay, Huando, and Parinacochas. After this knot of Cuzco and Parinacochas, in latitude 14° S., the Andes present a second bifurcation, and north- ward the two chains lie on the east and west of the river Jauja. Fig. 8.—Annual variation of rainfall at Cailloma during seven years. @Raimondi, El Peru, Volume I, page 15. GEOLOGY OF PERU——ADAMS. 391 The eastern chain extends on the east of Huanta, the convent of Ocopa and Tarma, the western chain passes Castrovereyna, Huan- cavelica, Huarochari, and Yauli, inclosing a lofty table-land. In latitude 10° 11’ the two branches unite in the knot of Huanuco and Pasco (Cerro de Pasco). From this point northward the Andes divide into three chains. The eastern lies between the Huallaga and Pachitea (Ucayali) riv- ers, the second or cen- tral between the Hual- laga and the Maranon, while the third hes be- tween the Maranon and the coast. The eastern range lowers to a range of hills, and is lost in latitude 6° 15’ on the west of Lamas. The central, after forming the rapids and cataracts of the Amazon, turns to the northwest and joins the knot of Loja in Ecua- dor. From the most cer- tain information which he obtained he concluded that to the east of the chain which passes to the east of Lake Titicaca and northward to Huanuco a wide mountainous land is situated, which is not . a widening of. the east- tern chain itself, but rather that it consists 6. 4—Monthly variation of rainfall at Cailloma during seven years. SEPTEMBER OCTOBER NOVEMBER DECEMBER & < % > 2 x 0 = > a q of heights which sur- round the foot of the Andes like a penumbra, filling in the whole space between the Beni and the Pachitea (Ucayali). Humboldt also made interesting comments on the direction of the Andes. He noted that in Chile and Upper Peru (Bolivia), from the Straits of Magellan to the parallel of Arica (18° 28’ 35’’ S.), the whole mass of the Andes runs from south to north in the direction of a meridian at the most 5° NE., but from the parallel of Arica the coast and the two Cordilleras east and west of the alpine lake of Titicaca abruptly change their direction and incline to the northwest. 88292—sm 1908S——26 392 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. In this region, as in general in every considerable widenings of the Cordillera, the grouped summits do not follow the principal axes in uniform and parallel directions, and he remarked that the general disposition of the Andes in this latitude is well worth the attention of geologists. From where the Cordilleras unite in the knot of Cuzco (Vilcanota) their direction is N. 80° W. He calls attention to the fact that the direction of the coast follows these changes, and remarks that the parallelism between the coast and the Cordilleras of the Andes is a phenomenon the more worthy of attention as it occurs in several parts of the globe where the mountains do not in the same manner form the shore. DESCRIPTION BY RAIMONDI. It is to be regretted that Raimondi did not publish a description of the Andes. However, his writings contain much information, and in his edited notes published in the chapter “Apuntes Orograficos,” in Volume IV of El Peru there is a partial description of the Cordilleras. He adopted the nomenclature of Humboldt. The Andes is used as a general term for the whole mountain system, and the various branches are spoken of as “ Cordilleras.” The branch to the east of Lake Titicaca he called the “ Cordillera Ori- ental” and the one to the west the “ Cordillera Occidental.” The union of these branches to the north of Lake Titicaca he calls the “Knot of Vilcanota,” taking the name from a snow-capped peak. From this knot northward he recognized three branches instead of the two somewhat vaguely described by Humboldt. The Cordillera Occidental follows the direction of the coast. The Cordillera Cen- tral separates the valleys of the Apurimac and the Vilcanota or Urubamba rivers, while the Cordillera Oriental separates the inter- Andean region from the forest region of the interior. These three Cordilleras unite in the Knot of Cerro de Pasco, from which point northward three branches diverge. The Cordillera Occidental for a portion of its way is divided into two, the western of which is known as the “ Cordillera Negra” (Black Cordillera) and the eastern or main one takes in that region the name “ Cordillera Blanca ” (White Cordillera) because of its snow-covered peaks. The Cordillera Cen- tral separates the Maranon and Huallaga rivers, while the Cordillera Oriental separates the Huallaga from the Pachitea and Ucayali. The Cordillera Central describes a curve, and is cut by the Maranon at the falls of Manseriche. The Cordillera Oriental lowers, and is cut by the Huallaga at the Falls of Aguirre and then runs in a north- west direction and joins the Cordillera Central. Humboldt states that it dies out in latitude 6° 15’.. With this exception, it will be seen that in the northern part of Peru the description by Raimondi does GEOLOGY OF PERU—ADAMS. 393 not differ materially from that by Humboldt. Raimondi gives a description of the Cordillera Occidental and notes a list of 42 of its passes, which vary from 2,186 meters to 5,075 meters. From Huama- chuco in latitude 7° 45’ southward the 27 passes are more than 4,000 meters above the sea. The lowest pass is that of Huarmaca, in the department of Piura, which is 2,180 meters. His further description of this Cordillera as to structure, age, and snow line, etc., will be given under other heads in this paper. Here, however, it will be noted that he says the southern part of the Cordillera Occidental is not a single range, but rather a broad ele- vated band or high plateau, on which are situated volcanic peaks. It may perhaps be added here with propriety that the Continental Divide is a continuous range and that the volcanic peaks do not fol- low the Cordillera, but are found in an irregular double line crossing the western part of the high plateau. The relation of this line of peaks to the change in direction of the Cordillera is not unlike that of a string to a bow. Tt will be remembered that Humboldt spoke of a mountainous area to the east in the forest region. Raimondi did not touch on this point, and indeed it is not yet possible to tell just what is the disposi- tion of the mountains of this region, for although many explorations have been made the wooded country has prevented the mapping of the topographic features. The Cordillera Central, according to Humboldt, joins the Occidental in the knot of Loja, in Ecuador. Perhaps Raimondi did not ttouch on this point in his description because Loja is outside of Peru, and consequently beyond the limit of his explorations. He seems to have accepted the statements of Humboldt in his mapping. é Wolf, however (1892), in his description of the Andes, says that he does not agree with the opinion that the Cordillera Oriental unites in the knot of Loja, as is shown on the map of Ecuador by Santiago y Morona and of Peru by Raimondi. He states that the Cordillera cut by the Pongo de Manseriche (Falls of Manseriche) is the last branch of the Peruvian mountains which reaches the Amazon. It appears not to be very high, since explorers speak of 600 meters at the locality of the falls, and he thinks that to the north it lowers and is lost in the plains between the rivers Santiago and Morona. Wolf also says that to the east of Ecuador from where the rivers are navigable the country is a great plain, with only small areas of gradual undulations, and that the high mountains of the old maps, as also those of Raimondi, are imaginary and do not exist. The accompanying sketch map (pl. 1) shows the disposition of the Cordilleras according to the foregoing description. The Ecuadoran portion is from the sketch published by Wolf, 394 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. THE AMAZON PLAINS REGION. It is to be regretted that so little systematized information is avail- able concerning the Amazon region. It has been explored principally along its great waterways, and the forest has prevented travelers from obtaining comprehensive views of its physical features, which are of relatively minor relief. There are some grassy plains. These are of insignificant extent as compared with the tree-covered area. Most of the sheets of Raimondi’s map in the Amazon region are without hachures, and Wolf has called attention to the fact that the mountains shown to the east of Ecuador and in a region which Raimondi did not visit are wholly fanciful. A chain of hills or an escarpment gives rise to the falls of the Madierra River, but further than this there is little found in the writings of explorers excepting the mention of bluffs along the streams and occasionally hilly areas. Accordingly, the region must be for the present dismissed without further attempt to describe or outline its physical features. SEDIMENTARY FoRMATIONS. CAMBRIAN. The Cambrian has not been identified in Peru by means of fossils. In some instances in the literature the Cambrian has evidently not been considered as a separate era, but has been included in the Silurian according to former usage. Accordingly formations have been discussed in connection with the Silurian which may be of Cambrian age. Steinmann (1904) has described green slates near Chanchamayo, which he says are surely pre-Silurian, but the ab- sence of fossils does not permit of their age being proved. He men- tions* having lost his collections of fossils from Bolivia which would have thrown light on the Cambrian and Silurian formations. SILURIAN. Tn his section from southern Peru into Bolivia d’Orbigny (1848) described the Silurian as represented in the Cordillera Oriental, where it has associated with it granite, which he stated forms the axis of the mountain range and constitutes some of the highest peaks. — Forbes (1861) outlined the area of the Silurian as extending from north of Cuzco in Peru along the Cordillera Oriental into Bolivia and southward to beyond Potosi. He found it to present physical features similar to the Silurian of Europe. He says that it consists @Jntroduction to paper by A. Ulrich on ‘ Paleeozoische Versteinerungen aus Bolivien.” GEOLOGY OF PERU—ADAMS. 395 of clay slates, shales, and quartzites, but he found no limestones. The fossils which he collected were examined by Salter and showed that probably the whole Silurian is represented. Forbes called attention to the fact that the formation contains quartz veins, and that these have given rise to auriferous gravels. He contradicted the state- ment of d’Orbigny that the peak Illimani in Bolivia is a granite peak as shown in the section, and says that Illimani and Illampu (Sorata) are composed of slates. Raimondi (1867) described the Cordillera Occidental as contain- ing slates cut by quartz veins carrying gold, and later (1873) in out- lining the geology of the Department of Ancachs he classes the slates as Silurian. In southern Peru Balta (1897) has classed the slates in the Prov- ince of Carabaya and Sandia as Silurian because of the presence of graptolites, and this classification was followed by Pflucker* who, however, contributed little to our knowledge of the Silurian. Ochoa, in his bulletin? on the Province of Huanuco, in the central part of the Peruvian Andes, makes a brief reference to the finding of graptolites near Huacar, from which fact he concluded that the Silurian is present there. Steinmann (1904) identified by means of graptolites the lower Silurian in the region of Tarma, also in the central region of the Peruvian Andes, and he states that the granite associated with the Silurian in the Cordillera Oriental made its appearance in lower Silurian time. Farther to the north Raimondi (1873), in describing the geology of the Department of Ancachs, states that in the Province of Huari, near Uco, in the valley of the Maranon, there are older sediments with a great formation of talcose slates with quartz veins, which he refers to the Silurian, although he did not mention any fossils. He also states that there is a similar area on the western slope of the Cordil- lera Nevada (Occidental) at Pallasca. Farther to the north and in the foothills of the Cordillera Occidental, in passing over the divide from Motupe to Olmos and in the vicinity of Olmos, the writer saw extensive exposures of slates cut by numerous quartz veins and stringers which have been prospected for gold. Mention is here made of the area because of its resemblance to the Silurian, but it should not be definitely classed until fossils have been found. A paper which has an important bearing on the paleontology of the Silurian was published by A. Ulrich (1892) describing an ex- 2JInforme sobre los yacimentos auriferous de Sandia, Bol. del Cuerpo de Ingenieros de Minas del Peru No. 26, 1905, Luis Pflucker. > Recursos minerales de la provincia de Huanuco, Bol. del Cuerpo de In- genieros de Minas del Peru No. 9, 1904, Nicanor G. Ochoa. 396 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. tensive collection of fossils from the Silurian and Devonian of Bolivia made by Steinmann. Inasmuch as the same faunas probably extend into Peru the descriptions of the fossils will be of value when similar studies are undertaken farther northward. Recently Dereims (1906) has described the occurrence of the Silurian at many places in Bolivia, some of which are near the border of Peru in the Titicaca basin, although most of them are to the south in the Cordillera Real (Oriental) of Bolivia, but he has not yet described his collections of fossils. DEVONIAN. The first recognition of a Devonian locality which has a bearing on the geology of Peru was by d’Orbigny (1842), who made collec- tions in the Titicaca Lake region in Bolivia and found fossils which he described as characteristic of that period. Forbes (1861) when in the field did not distinguish the Devonian, but included it with the upper Silurian. Later he was induced by Salter, who studied the collections of fossils, to show the Devonian in his section because of the finding of Phacops latifrons, which is admitted to be a truly Devonian species. Forbes’s localities are in Bolivia, near Lake Titicaca. Mention has already been made of the collections from Bolivia made by Steinmann which were studied by A. Ulrich (1892) and found to contain an interesting series of Silurian and Devonian fossils. The descriptions by Ulrich will be of value when the Devo- nian in adjacent parts of Peru receives critical study. Still later Dereims (1906) has described the occurrence of the Devonian in Bolivia, near Lake Titicaca. He says it consists of sand- stones of different colors and thicknesses, alternating with shales of less importance. He obtained a collection of fossils, some of which he mentions, but he has not yet published his paleontologic studies. All the foregoing literature pertains to Bolivia, but it has a direct bearing on the geology of Peru, since the Devonian undoubtedly ex- tends across the border in the Titicaca basin. Thus far no Devonian fossils have been described from Peru, but Duefas* (1907) obtained fossils from Taraco northwest of Lake Titicaca which Bravo has reported to be Devonian, although he did not determine them specifically. CARBONIFEROUS. The Carboniferous in Bolivia was studied by d’Orbigny (1848), who described a number of fossils. This was the first information which gave a definite reason to suppose that the Carboniferous exists @Wnrique I. Dueflas. Bol. del Cuerpo de Ingenieros de Minas del Peru No. 53, p. 156. See footnote. GEOLOGY OF PERU—ADAMS. 397 in Peru, since the localities are very near the border. D’Orbigny also referred the rocks at Arica to the Carboniferous on very slight evi- dence, but this has been refuted by Forbes. The writer * found fos- sils at Arica, which, according to Bravo, are Cretaceous, although he did not determine them specifically. The Carboniferous areas examined by Forbes (1861) are on the peninsula of Copacabana and the projecting headland opposite on Lake Titicaca. On account of a declaration of war Forbes was placed in a suspicious position, since these localities are on the frontier be- tween Peru and Bolivia. He, however, obtained a collection of fossils which were determined by Salter. Forbes states that the Carbonif- erous is also to be found to the north of Lake Titicaca. The fossils collected by Agassiz (1876), together with some others, were studied by Derby (1876), who described 9 Carboniferous spe- cies from Yampata and the island of Titicaca. He also found a Spirifer in materials brought by James Orton from the Pichis River, and in his notes says that he has recognized Productus and Strepto- rhynchus from near Mayobamba in northern Peru. Agassiz, in the notes accompanying Derby’s paper, states that specimens of Fusulina were sent to Mr. Brady for identification. The notes as to the occur- rence of the Carboniferous are by Agassiz, who says that near Lake Titicaca it lies in a rather limited elongated basin, with the axis in a northwest-southeast direction. He identified the Carboniferous at Vilca, Santa Lucia, and Sumbay, and says that Mr. Orrego stated that Carboniferous is found as far north as Caylloma, and quotes Orton as saying that Raimondi reported he had traced the Carbonif- erous series to a height of 1,400 feet on the Apurimac at a locality intermediate between the Pichis River and Cuzco. It would seem to the writer that until fossils are found the identification of the Car- boniferous at the places mentioned by Agassiz, and especially those reported by Mr. Orrego, should not be definitely referred to the Carboniferous. The writer in journeying to Caylloma observed sedimentary formations which appear to be Cretaceous. Balta (1899) reviewed the Carboniferous of Peru and published a sketch map showing two areas in which the Carboniferous had been shown to exist, namely, in the Titicaca basin and the locality from which Orton’s Carboniferous fossils were obtained. He added noth- ing especially new. A small Carboniferous area was reported? by Fuchs (1900) as being found in the peninsula of Paracas, just south of Pisco, on the Pacific coast. The formation there contains some thin coal which 4 See Boletin del Cuerpo de Ingenieros de Minas del Peru, No. 45, p. 19, 1906. + Nota sobre el Terreno Carbonifero de la peninsula de Paracas, F. C. Fuchs, Bol. de Minas, T. XVI, 1900. 398 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. an attempt is being made to exploit. With the coal, fossil plants were found by Fuchs. This is an important addition to our knowl- edge of the distribution of the Carboniferous because of the geo- graphic position of the area. Steinmann (1904) reported the finding of a few characteristic Carboniferous fossils southeast of Tarnia. The Carboniferous in Bolivia, especially in the region of Lake Titicaca, was studied by Dereims (1906), who describes the formation as composed of sandstones and shales, with a bed of dark limestone at the base and with coal beds. He investigated the coal four leagues north of Mocomoco, at Ococoya and Calacala, where it does not exceed 80 centimeters and consists largely of shale impregnated with carbonaceous matter and is not workable. In the peninsula of Copo- cabana, near Yamupata, he saw thin beds of coal, which have for- merly been worked, but the coal is mixed with shale and contains so much sulphur that it can not be used. He states that on the island of Titicaca it is of the same general character. His conclusion in regard to the Carboniferous in Bolivia is that it is the lower or Dimantian stage, and is everywhere marine and contains no workable or good coal. PERMIAN. The Permian is not known to be present in Peruvian territory. Certain sandstones in Bolivia which extend into southern Peru in the Titicaca region were early classed as Permian or Triassic by Forbes because of their resemblance to the typical Permian of Russia described by Murchison. Forbes, however, states that no fossils hav- ing been found, the age of the beds is a question for inquiry. The formation contains salt and gypsum beds and native copper, the celebrated mines of Cora-Cora being found in them. Steinmann (1906) has discussed the Cora-Cora copper deposits and has given the name Puca sandstone to the formation in which they are found. He says that the formation comprises the youngest ma- rine sediments in Bolivia and has a thickness of more than 1,000 meters. By the finding of fossils near Potosi, in southern Bolivia,* in related formations a higher age than Jura is indicated, and accord- ingly he assigns them to the Cretaceous. Dereims (1906) says that at Santa Lucia, near Potosi, he found reddish sandstones and reddish gypsiferous shales with some beds that are calcareous, which are of Permian age. The calcareous bed is full of Chemnitzia potosensis, first described by d’Orbigny. He re- marks that d’Orbigny has referred this formation to the Trias on lithologic grounds, but from the fossils it appears that it is Permian- 4Compare Steinmann, Hoek, and V. Bistraus. Zentralblatt fiir Mineralogie ete., 1904, p. 3, zur Geologie des sudostichen Boliviens. GEOLOGY OF PERU—ADAMS. 399 Carboniferous or Permian. It will be remembered that d’Orbigny described Chemnitzia potosensis from the Triassic, but the diagnostic value of the genus for indicating the Carboniferous or Permian may well be questioned, since the genus is also found in the Mesozoic. Moreover, it will be recalled that the evidence by Steinmann just cited is opposed to the conclusions of Dereims. TRIASSIC, D’Orbigny (1842) referred to the Triassic a series of variegated reddish sandstones in Bolivia. He found a number of fossils but mentions only one, Chemnitzia potosensis, the others having been lost. The age of these beds seems to still be in doubt, Dereims having re- ferred them (1906) to the permo-Carboniferous as has already been mentioned. Later Forbes (1861) commented on the classification by d’Orbigny and states that it would appear that d’Orbigny proceeded on the supposition that no link in the geologic chain should be deficient. Forbes classed these rocks as Permian or Jurassic, but stated that their age is a question requiring more study. Raimondi (1873) in his volume on the Department of Ancachs classed as Triassic certain red sandstones and shales with salt and gypsum. This seems to have been done in accordance with the gen- eral relations of the rocks and to make the geologic succession com- plete. It will be remembered that the fossils sent by Raimondi to Gabb were not given close diagnostic values, and so the classification by Raimondi has really little value. In several places Raimondi speaks of the Triassic as being present, but unfortunately little reli- ance can be placed on this. According to Steinmann’s later writings (1904) the red sandstones and shales with salt and gypsum beds are to be classed as Cretaceous (Lower Liassic) .? JURASSIC. D’Orbigny (1842) found no fossils of Jurassic age and did not color any part of his section as Jurassic. He discussed the prob- abilities of its being present in South America. Crosnier (1852), in his explorations on the east slope of the Cor- dillera Occidental, found some fossils which were determined by M. Bayle as Jurassic. He mentions an Arca like Arca gabnelis of the Neocomian. Also an Ammonite from near Oroya was likewise de- termined as Jurassic. Forbes (1860) classed as Jurassic or Permian a series consisting principally of sandstones aggregating more than 6,000 feet. These 2 Bol. No. 12, p. 24. 400 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. rocks were classed by d’Orbigny as Devonian and Carboniferous and in part Triassic, but he cited no fossils. Forbes says that the beds contain plant remains (coniferous indeterminable) and he was in- formed that a complete Saurian head had been extracted from the beds by M. Ramon Due, but was not successful in obtaining it nor some fossil bones and teeth now in the Museum of Avignon in France, sent there by M. Granier of La Paz. The character of these beds, as already stated in describing the Permian, is like the typical Permian of Russia. Forbes concluded that their age must await the finding of fossils. Raimondi (1873), in his study of the Department of Ancachs, classes as Jurassic certain formations containing coal and yielding ammonite fossils. However, he had no other determination for his fossils than that furnished by Gabb, which was not very critical and so we must rely on later work for the differentiation of the Jurassic. It will be seen later that the plants and invertebrates from the coal horizon of the Cordillera Occidental have been shown to be Creta- ceous. However, Raimondi in some instances was probably correct in assigning formations to the Jurassic, since it is now known to be pres- ent and has yielded numerous fossils. Bravo has called attention to the fact that Gottsche* has made mention of an ammonite from Morococha which is in the Freiburg collections. Fossil ammonites from Huallanea, in the Department of Ancachs, collected by Durfeldt and belonging to the Freiburg Museum, were studied by Steinmann (1881) and considered by him as indicating the Tithon (which is homotaxial with the Portlandian) and belong- ing in the upper part of the Jurassic. CRETACEOUS. The island of San Lorenzo at Callao was examined by Dana, and his description is published in the report of the Wilkes expedition (1849). He made some detailed sections of the rocks and found some fossils which he considered as indicating the oolitic. He refers in a footnote to the fact that James Delafield had reported ® upon some fossils which Doctor Brinkerhoff had collected from the island and presented to the New York Lyceum of Natural History. Dela- field did not venture an opinion as to the age of the fossils. Doctor Pickering, who was with Dana, found an ammonite at the head of the Chancay Valley at an elevation of 15,000 feet in rocks similar to those of San Lorenzo Island. This specimen is described in the appendix of the report as Ammonites pickeringi. Some fos- sils from Trujillo are also figured. @Uber Jurassiche versteinerungen aus der Argentinische Cordillere. Dr. Carl Gottsche, Cassel, 1878. 6 Amer. Journ. Sci., Vol. 38, p. 201, 1839. GEOLOGY OF PERU—ADAMS. 401 D’Orbigny discussed the occurrence of the Cretaceous in South America, and in his section shows an extension of porphyritic rocks on the west slope of the Cordillera Occidental; he did not differ- entiate the Cretaceous, but evidently included them with the por- phyries with which they are interbedded. In the section which Forbes made from Arica to Bolivia he classi- fied (1861) as oolitic (Liassic) the rocks at Arica, which he describes as shales, claystones, and embedded porphyries, and stated as his rea- son for doing so that to the south of the district which he studied the rocks are abundantly fossiliferous and had yielded to the re- searches of Bayle and Coquand and Phillipi about 35 species of recognized oolitic forms. On his map he showed a considerable ex- tent of oolitic in the Cordillera Occidental of southern Peru. Apparently, Raimondi attempted to identify the fossils which he collected, although he did not describe them. He evidently used the fossils as a guide in determining as best he could the age of the sedi- mentary formation, which he discusses in his various writings. When he sent his collections to Gabb to be described he accompanied them by a letter (1867) in which he outlined the geographical distribution of the sedimentary formations of Peru. According to his idea, Cretaceous (with Jurassic, Lias, and Trias) is distributed principally in the western Cordillera. He thought the stratified rocks near the Port of Ancon, at San Lorenzo, near Callao, and at Chorillos, to be Jurassic or Liassic. These localities have since proven to be Creta- ceous, as will soon appear in this paper. Unfortunately, Gabb’s de- termination of the Mesozoic fossils was delayed and, moreover, he did not give to them such diagnostic value as would help Raimondi to revise his ideas in his later writings. In his volume on the Department of Ancachs he classed (1873) as Cretaceous certain limestones with echinoderms, oysters, and other fossils. This seems to be correct as viewed in connection with the determination of the Cretaceous in other localities, where it con- sists largely of limestone and contains similar fossils. Tn his geological sketches (1876) Agassiz states that Mr. William Chandless, upon his return from the River Purus, presented him with fossil remains of the highest interest and undoubtedly belong- ing to the Cretaceous. They were collected on the River Aquiry, latitude 10°-11° south, longitude 67°-69° west, in localities varying from 430 to 650 feet above sea level. Among the material, remains of a Morosaurus and of fishes were found. Chandless¢ says that the material identified by Agassiz consisted of two perfectly preserved vertebrae of Morosaurus. These are the only vertebrate remains thus 2“ Notes on the River Aquiry, the principal affluent of the Purus,” William Chandless, Journal Royal Geogr. Soe., Vol. 36, p. 119. 402 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. far mentioned as from the Cretaceous of Peru. It may not be improper to recall, in this connection, that Forbes in discussing the Permian or Triassic of Bolivia says that he was informed that a complete Saurian head had been extracted from the beds and also some fossil bones and teeth. This material appears never to have been studied critically and not even a generic name has been applied. The Mesozoic fossils sent to Gabb by Raimondi were described (1877) and figured, but since then they have not been reviewed crit- ically and studied in connection with further collections, excepting that the descriptions have been referred to by later workers. The opinions which Gabb ventured to give were not very definite, as would naturally be the case in dealing with meager and scattered collections. In several instances he simply stated the age of the beds according to the opinion of Raimondi. Gabb gave with his paper a synopsis of the South American invertebrate paleontology and a bibliography of South American paleontology. A number of fossils collected by Durfeldt from the coal-bearing formation at Pariatambo, Peru, and belonging to the Freiburg Museum, were studied by Steinmann (1881) and determined as indicating the Albien and marine origin of the beds. This was the first paper by Steinmann dealing critically with the paleontology of Peru. To him and his colaborers we are indebted for'a number of subsequent papers which are published under his supervision as Contributions to the Geology and Paleontology of South America. The material from Peru studied by Gerhardt (1897) consisted of a block containing fossils from Morococha (Pariatambo), sent by Don Jose Barranca, of Lima, to Doctor Steinmann. By dissolving the stone in acid a small fauna was obtained. The additional fossils from the Strasburg Museum were those collected by Reiss and Stubel from the same place. With this material he was better able to determine the age of the beds which Gabb had considered as Liassic and Steinmann had determined as Albien on the border between upper and lower Cretaceous. He concludes that the coal-bearing beds of Pariatambo are of marine origin, and that certainly in Albien time in Peru a fauna reigned which was related to that of Europe and north Africa. In studying the fossils of Venezuela he identified Ammonites Andii Gabb from Peru with a Venezuela Lenticras, and so concluded that the lower Senon was present in Peru. The paleontological paper on the Cretaceous of South America, by Paulcke (1903), in so far as it pertains to Peru, is a filling out of the fauna studied by Gerhardt and extends our knowledge of the upper Cretaceous. Most of the specimens were collected by Reiss and Stubel in Cajamarca and nearby places in northern Peru, but some were collected by J. Bamberger. He found the Senonian of the GEOLOGY OF PERU—ADAMS. 403 upper Cretaceous represented. He says, in summing up concerning the lower Cretaceous, that in Peru the only highest part of the lower Cretaceous (the Albien) is certainly known and the Neocomian prob- ably may be present. In various bulletins? of the Corps of Engineers of Mines of Peru J. J. Bravo has published (1904-1906) determinations of Cretaceous fossils and has described some species. This is the most important work done in paleontology by a Peruvian. Through his efforts the corps 1s gradually acquiring a collection of fossils and developing a paleontologic literature. Bravo has called attention to the fact that previously Pflucker y Rico had collected fossils and given a relation ” of localities and a list of fossils obtained in the districts of Yauli (Morococha), but the collections were lost. He also cites two species of Pseudo-ceratites from Yauli, described by Hyatt.¢ In 1904 Habich, in his report on the coal deposits of Checras, in the Province of Chancay,? mentions the finding of Cretaceous fossils in limestones and plants in the coal-bearing beds. Similarly Malaga Santolalla (1904) found fossils in Hualgayoc ¢ and concluded that the middle or upper part of the Cretaceous is represented there. He also gives’ a lst of fossils from the Province of Cajamarca described by various authors. In his report on the Province of Colendin 9 he likewise gives a list of Cretaceous fossils. Lisson (1905) collected a few fossils from near Chorullos, just south of Lima, and described” some Annelid tubes, and a new species Sonnerata Pfluckeri and redescribes S. Raimondi- anus Gabb. In the winter of 1903-4 Steinmann made some collections in the Cordillera east of Lima and from the Island San Lorenzo in front of Callao. This material was studied by Neumann, who also included some fossils in the Hamburg Museum, from Lucha, and the quebrada of Huallauca, in the Province of Ancachs. In his report (1907) he says that up to this time the Cretaceous was very incompletely known and that according to his knowledge no lower Cretaceous had been found. The fossil plants from San Lorenzo, studied by Neu- 4 Bulletins Nos. 10, 19, 21, 25, 85, 51, dealing with the Provinces of Cajatambo, Cajabamba, Pataz, the district of Morococha, the Provinces of Jauja and Huan- eayo, and the Province of Huamachuco, respectively. + Apuntes sobre el distrito mineral de Yauli, Annales de Const. Civiles y de Minas del Peru, Tome III, 1883. ¢ Pseudo-ceratites of the Cretaceous, U.S. Geol. Survey Monograph XLLIV, 1908. ¢@ Bol. de Cuerpo de Ing. de Minas del Peru No. 18, E. A. V. de Habich. € Bol. No. 6. f Bol. No. 31. 9 Bol. No. 32. : "Bol. No. 17, Los Tigillites del Salto del Fraile y algunos Sonneratia del Morro Solar. Carlos I. Lisson. 404 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. mann, were found to be Neocomian (Wealdan) flora. The fauna from San Lorenzo was also referred to the Neocomian. The fauna from Huallauca, Lucha, and Chaco was found to be Albien, with the Rotomagien (?) lower Cenomian also represented at Huallauca. The Santonien was determined at Abra de Charata (between Oroya and Tarma), and from Lucha and Huallauca and Le Quinua. The rich material described increased the number of Senonian fossils from Peru and contained some entirely new forms, while the Wealdan flora was the first found in South America. It will be remembered that Steinmann (1906) has referred to the Cretaceous the Puca sandstone formation, so named by him and which includes the Cora-Cora copper mines of Bolivia. This has already been discussed under the heading of the Permian. The Puca sandstone extends into Peru. TERTIARY. Marine Tertiary of the Pacific coast. The marine Tertiary of the southern coastal plains was described by Forbes (1860), who called it the “ Tertiary and diluvial formation of the coast.” This formation is also shown in the section by @Orbigny (1842) and by Pissis (1856), who, however, did not de- vote much attention to it. According to Forbes the Tertiary extends inland from the stretch of low coast lying to the north of Arica, forming gently sloping plains which show evidence of ancient sea beaches. The plains are composed of sand, earth, and gravel, with abundant fragments of porphyritic rocks from the mountains to the east. Forbes mentions a trachytic volcanic formation seemingly con- temporaneous with the plains formation, which appears to have been deposited while they were still under water. This volcanic material is in the form of tuffs and ashes and has subsequently been covered by other deposits. In discussing the saline deposits of the coastal plains (especially in territory that now is in Chile) Forbes advances the idea that with the exception of the boracic-acid compounds, the presence of which is due to voleanic causes, all the salines are such as would be left by evaporating sea water or by mutual reactions of saline matters thus left. This lacustrine hypothesis he applies to the nitrate deposits and states that the chain of hills to the west is such as might on elevation have inclosed a series of lagoons in tidal communication with the sea. For the saline deposits at high elevations he includes the factor of rainfall and states that they are not so characteristic of the lagoon type as the lower deposits near the coast. The next reference to the Tertiary of the coast is concerning the formations in the northern coastal plains. Among the fossils sent GEOLOGY OF PERU—ADAMS. 405 by Raimondi to Gabb there was a collection from Payta. Gabb, in addition to describing them (1869), states that one set of four or five specimens was made up of extinct forms, while the remainder appeared to be Pliocene. Orton (1870) mentions some fossil shells of living species which he collected from the biuff at Payta and which were determined by Gabb. The portion of the Tertiary formations of the northern coastal plain lying between Payta and the Ecuadorian frontier was explored and described by Grzybowski (1899). He traveled from Payta to Talara, thence to Tumbez, and up the Tumbez River to Casadero, from which place he returned to the coast. He made the following divisions of the Tertiary: PMOCenes= 2 oale ess Conglomerates==——— = Payta formation. Hines Niiocencuaae Brown, shales22225 ss ss2 Talara formation. Sandstone=ts22 ea 2) b=. Zorritos formation. Lower Miocene____- Bituminous shales_______- Heath formation. Oligocenes=2252222= Hieroglyphic and massive sandstone==— 22 Ovibos formation. He collected and described fossils from these formations. The Oligocene, however, he distinguished more from stratigraphic rela- tions than by fossils. The paper is accompanied by a sketch map and sketch sections showing the localities where the formations were found. He observed a granite outcrop at Rica Playa, on the Tumbez River, and called certain rocks in the region of Casadero Paleozoic, but did not identify them by means of fossils. He regarded the Pale- ozoic as pushed up through the broken Tertiary. At Payta he noted a shale formation (no fossils) on which the Tertiary rests. Lacustrine Tertiary of the Sierra. In the Bolivian Plateau d’Orbigny (1842) described an ancient alluvial and pampean formation, the relations of which are shown in the section accompanying his report. Pissis (1856) also showed this formation but with an interbedded stratum of volcanic tuff in the Titicaca basin region. Forbes (1860) described the same deposits under the name “ De- luvial of the Interior” and explained that it varies from place to place according to the rocks from which it is derived. In his section he shows locally a bed of trachytic tuff and explained that it is seen in the valley of La Paz, in Bolivia. Agassiz (1876), in the paper accompanying his hydrographic sketch of Lake Titicaca, noted the lake deposits in the Titicaca basin and said that there are terraces up to 300-400 feet above the present level of the lake, and made some comments as to its former exten- 406 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. sion when at that stage. The most definite of these comments is, that in the direction of Pucara (to the northwest) the lake reached to Sta. Rosa. He also remarked that Tiahuauaco, which is a ruin of a temple older than the Inéa civilization, is 75 feet above the present level of the lake. From this we may judge that since the Indo-humanic period, as recorded by the oldest monuments in the region, the lake has not fallen more than 75 feet. In journeying to the departments of Huaucavelica and Ayacucho, Crosnier passed through the valley of Jauja, where he found a for- mation which he considered (1852) to have been formed in an inter- Andean lake about 30 miles long and from 9 to 12 miles wide. The deposits are described as consisting of clays and gravels such as would have been transported by streams. He estimated the thickness at from 600 to 700 feet (200 to 300 meters). In the basin of Ayacucho he also found a Tertiary deposit consisting of marls and tuffs. No proof as to the age of these beds was given, but they were classed as Tertiary from their general relations. In his bulletin on the Mineral Resources of the Provinces of Jauja and Huancayo,* Duenas (1906) says that the valley of Jauja was in former times the bottom of a great lake, which, by cutting the canyon which is its natural outlet, has gone dry. The lake deposits he con- sidered to be of glaco-fluvial origin. He published two photographs of river terraces cut in these deposits. Duenas does not refer to the description of the lacustrine formation by Crosnier, with which he no doubt was familiar. The action of glaciers in connection with fluvial action brings in a new factor to explain the origin of the beds. The author has seen a portion of the Jauja Valley, and is inclined to doubt that glaciers contributed directly to form the deposits, al- though products of glacial action were undoubtedly brought in by rivers. If, however, lake beds were all deposited during the glacial period we must refer them to the Pleistocene of the Quaternary and not to the Tertiary, as was done by Crosnier. This is a matter for further study. To the northwest of the Titicaca Basin, Duefias (1907) observed certain deposits in the Department of Cuzco,’ which he says are prob- ably of lacustrine origin. They occur at several localities, differing considerably in character. He mentions beds of tuffs and a stratum of tripoli, in which he reported finding sponge spicules. Because of finding these spicules he says that one might be induced to suppose that in Tertiary times southern Peru was under the Pacific Ocean. This is an unfortunate remark, since it is liable to be perpetuated in the literature by being quoted without questioning whether spicules @ Bol. del Cuerpo de Ing. de Minas No. 35. b Aspecto Minero del Departmento del Cuzco, Bol. del Cuerpo de Ing. de Minas del Peru No. 53. Enrique I. Duenas, 1907. GEOLOGY OF PERU—ADAMS. 407 of marine sponges are actually present in the deposits. Although Duefias finally accepts the lacustrine theory for the deposits, he goes rather far when he remarks that it is nothing wonderful to suppose that Lake Titicaca once extended into the Department of Cuzco. From what the writer has seen of the topography it appears alto- gether improbable; and, moreover, the theory of local lakes would account in a more satisfactory manner for the occurrence of the for- mations. Tertiary of the Amazon region. James Orton, in his explorations of the upper Amazon Valley, collected some shells from Pebas, which he submitted to Gabb, who determined them (1868) as late Tertiary. Because of the finding of these shells, Orton refuted the theory of the glacial origin of the clays of the Amazon basin presented by Agassiz and discussed later in this report. Orton (1870) gives a description of the exposures along his route of travel. He says that along the Napo River the only spot where the rocks are exposed is near Napo village, where there is a bed of dark slate dipping east. Farther west, at the foot of the Ecuadorian Andes, the prevailing rock was found by him to be mica schist. The entire Napo country is covered with an alluvial bed on an average 10 feet thick. The formation of the bluff near Pebas he described as consisting of fine laminated clays of many colors, resting on a bed of lignite or bituminous shale and a coarse iron-cemented conglomerate. After Gabb described the collection of shells from Pebas, a larger collection was made by Mr. Hauxwell, a part from Pebas but most of them from 30 miles below Pebas, at Pichua. Among them Conrad found (1870) seven.species of Pachydon (Gabb),a genus which does not have any living representative and is very different from any existing fresh-water genus. He says that it is not possible to state without doubt what the relative stratigraphic position of the group may be, but if all the species are extinct it can not be later than Ter- tiary, and that it may have lived in fresh or brackish water, but it is certainly not of marine origin. A collection made by Mr. Steere at Pebas was examined by Conrad (1874), who questioned there being evidence of the marine origin of the shells. QUATERNARY. Pleistocene glaciation. OccURRENCE oF SNOW PEAKS. Humboldt, in his personal narrative (1814), called attention to the absence of snow peaks between the Nevada Huaylillas in latitude 7° 55’ and Chimborazo in Ecuador. 88292—sm 1908——27 408 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Raimondi (1873), in speaking of the Cordillera Occidental, says that snow peaks are numerous in southern Peru, but that the most colossal and gigantic are those in the portion known as the Cordil- lera Blanca, in the Department of Ancachs. Cerro Hundoy, in front of Caraz, is 6,828 meters high, while the bicuspate mountain Huas- can, which dominates Yungay, rises to an elevation of 6,668 meters in its northern peak and 6,721 meters in its southern peak. This is near the northern termination of the perpetual snow. He also states that Huaylillas is the most northern snow peak in Peru. In the Cordillera Central and likewise in the Oriental there are snow peaks which are mentioned by many writers, but thus far no special study of the distribution of the perpetual snow has been made. THE LOWER LIMIT OF PERPETUAL SNOW. Pentland (1830) made numerous observations as to the occurrence and lower limit of perpetual snow in southern Peru and in territory which is now in Bolivia. He placed the limit at 17,061 feet, and ar- rived at the conclusion that it is higher than would naturally be expected and especially when compared with peaks nearer the Equator. He attempted to explain this anomaly as due to aridity and excessive evaporation. Raimondi (1879) has given 14,700 feet as the average of the lowest limits in the Department of Ancachs. In the Cordilleras, in the southern part of Peru, he places the limit at 15,100 feet or more. He commented on the previous observations and explained that there seems to be a considerable error in Pent- land’s determinations of altitudes and considers the deductions from them as erroneous. Raimondi gives the following table of the gen- erally admitted elevation of the lower limits of perpetual snow: Meters. Ocor waksthie MOqUatOrse. «Rk ects ee ee Ee 4, 800 20 r SOE = in Wace Se os ie ee Ree eles eee eS ee 4, 600 AE SOS UE Ll ean Sek ML Soe ee St nes UN eee BE} ()() GOSaESOU LE Sect ESe ERY 2 Le ae BAS Baap ee Ok Sa eC eeee 1, 500 GLACIATION. After examining the evidences of glaciation in Bolivia and south- ern Peru, Hauthal* (1906) in a short notice gave as his opinion that climatic conditions similar to those of the present prevailed during the glacial period, but that a lower temperature, due to cosmic causes, gave rise to glaciers from certain centers, and that there was no gen- eral glaciation. Duenas (1907), in his report on the Department of Cuzco, examined the glaciated mass of igneous rock known as the “ Rodadero ” on the @Quartare vergletscherung der Anden in Bolivien und Peru, Zeitschrift ftir gletscherkunde, Band I, Heft 8, September, 1906, p, 203, GEOLOGY OF PERU—ADAMS. 409 hill above the town of Cuzco, and expressed his opinion that the whole valley in which Cuzco lies was occupied by a glacier. The evidence given for so great a glacier is not quite so complete as might be wished, at least its lowest limit should be determined. | LG GE o wy SEA LEVEL =----— = oS Sa a ar = Sa eno ap ayaa ah ie “fn o ee eee ere ee a 2 = Sea =— Conglomerate Sandstone Slate \=-===—-] Phylite ~S2== Pe Bes = Fic. 7.—Section at Paita, by Grzybowski. was also some strata in which a few marine shells are found and others in which phosphate nodules occur, but to an extent so limited that they have no commercial value. Farther south in the valley of the Rio Grande the Pisco formation is cut by the canyon of that river. The tributaries of the Rio Grande which flow past Palpa and Nazca have cut deep valleys, in the walls of which the forma- tion is seen to contain a mixture of rounded stones in a matrix of sand and clay materials, but with a sufficient amount of the white chalky matter which characterizes the formation to demonstrate that it is only a littoral phase of the Pisco formation. The Pisco formation is also found in the plains to the east of the port of Lomas, where the remains of a whale were seen by the writer, and in one of the. valleys which cut the plain a conglomerate of ma- rine shells was found. To the southward the plains narrow and the mountains come to the seacoast, but at Chala there is a small area of Pisco formation in which the beds consist largely of variegated clays. In the northern part of the plains, to the east of the Canete, the Pisco formation was found presenting a littoral phase, but containing 416 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. some of the white chalk material and some beds of impure concre- tionary limestones similar to what occurred at the type locality near Pisco. The so-called chalk material was analyzed by the Corps of Engineers of Mines and found to consist principally of silica, with small amounts of lime and alumina. A microscopic examination showed it to contain many diatoms and what appeared to be vol- canic ash. In traveling by steamer from Pisco to Lomas the Pisco formation can be seen forming the sea cliffs and rising to the table land of Ica. Although some fossils have been found, they have not been studied critically. The age of the Pisco formation is not surely known. The writer has assigned it to the Pliocene provisionally, since it is over- lain by deposits which are probably of Pleistocene age, and there is no information which shows the necessity of assigning it to an earlier time. TERTIARY OF THE SOUTHERN COASTAL PLAINS. The Moquequa formation. The writer has given this name to the formation which occupies the southern coastal plains. It has been described locally, by Forbes and others, as already mentioned in this paper, but no one had journeyed sufficiently over the plains to learn that it was coextensive with them. The strata which constitute it can be studied conven- iently in the valley of the Moquegua River, especially near the town of the same name. It is also well exposed in the valleys of all the streams which cross the plains, since they have cut deep canyons. The eastern limit of the formation is at the foothills of the Andes, and the western limit is formed by the chain of coast hills. It reaches to the Pacific Ocean in the interval between the coast hills of Peru and the Morro of Arica, which is the northern extremity of the coast hills of Chile. The character of the rocks which constitute the Moquegua formation has been well outlined by Forbes. They consist of sands with some clays, a large quantity of detrital material derived from igneous rocks, but especially noticeable are the thick beds of volcanic material which appear to have been deposited in water and interbedded with sands. In the valley of the River Vitor, which descends from the Andes past the volcano Misti which is located near Ariquipa, beds of lava may be seen which have de- scended from the volcano and extended over the plains, where they form a capping on the Moquegua formation. The age of the volcanic rocks is not certainly known, and there has been no opportunity to determine the age of the Moquegua formation, since no fossils have been found. It is generally stated that the volcanoes of southern GEOLOGY OF PERU—ADAMS. Peru began their activity in Ter- tiary times and some of them are still active, although no great lava flows have come from them in recent times. The writer has provisionally assigned the Pliocene age to the Moquegua formation, thus making it con- temporaneous with the Pisco formation to the north. There appears to be no reason for con- sidering it as of greater age, and in outlining the history of the coast the Pliocene age seems for the present satisfactory. The thickness of the Moquegua formation is variable, since it was apparently deposited in a trough between the coast hills and the foothills of the Andes (see fig. 8). From measurements made in some of the canyons a thickness of 1,500 feet may be assigned. QUATERNARY DEPOSITS. Pleistocene. THE PACASMAYO FORMATION, At Pacasmayo, in the southern part of the northern coastal plains, the sea cliff consists of stratified conglomerates mixed with sand and occasional clay beds (see pl.3). The formation is also well exposed at the mouth of the Jequetepeque and along that stream inland. At Eten the sea cliff consists of a homogeneous sandy clay. To the north of Eten for a considerable distance the coast is low near the shore and there are no good exposures, so that the writer has not been able to trace the Pacasmayo formation “OI ‘MOI}VMIOJ BNSonboy 9q} JO SUOT}BIII SUIMOYS WOTDIg—'g 13A31 vas At < A\ 4 t ) a4 Ae sa, AaeSar s av “ic Bovi,30-1243 L on umMoUUN eInqjons4s tras LSVO) JHL 5O SA90VHUSIL o > a 2 a ° 2 » aR » erdurrgy Au 417 418 PACASMAYD FORMATION AMOTAPE FORMATION Miocene PISCO FORMATION BARRANCO FORMATION Pleistocene Pliocene Yery recent Pleistocene Pliocene ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Fic. 9.—Section correlating the formations of the coast. farther in that direction. To the south of Pacas- mayo the coastal plains narrow until the mountains descend to the shore south in the valley of Viru. Throughout this extent the Pacasmayo formation is represented in its various phases. The age and relations of this formation will be more clearly understood when it is considered in connection with the Barranco formation next to be described, with which it has been correlated (see fig. 9). It is to be regretted that in the region of the Sechura desert the relations of the Tertiary formations of the north- ern part of the northern coastal plains and the Pacasmayo of the southern portion are obscured by the drifting sands, which obliterates any exposures which might otherwise be seen in this area of slight relief. BARRANCO FORMATION. At the valleys of the Pativilea, Huaura, Chancay, and Rimac rivers there are sea cliffs cut in what appear to be raised delta formations. In other val- leys to the south and north smaller areas of a similar formation may be seen (see pl. 4). At Tambo de Mora the sea cliff has the same character as at the mouths of the rivers, but there the forma- tion extends inland and northward continuously to the valley of the Cafete. The writer regards this area, which constitutes a part of the south-central coastal plains, as furnishing the key to the proper understanding of the Barranco formation. It un- doubtedly les upon the Pisco formation, although its relations to the latter south of the Chincha River are not very clear because of the intervention of the wide stream valley. Its relation to the Pisco formation may also be seen in the Cafete Valley. The character of the materials and the degree of cementation in the Pacasmayo and Barranco forma- tions is similar. No fossils have been found with the excep- tion of comminuted shells and occasional branches of trees. The writer has assigned the Pleistocene age to these deposits and would correlate the coarse sediments and bowlders which have been deposited in the form and structure of deltas with the in- GEOLOGY OF PERU—ADAMS. 419 ereased volume of the streams and the erosion which accom- panied the glacial period.* RECENT FORMATIONS OF THE COAST. The recent formations consist principally of materials transported by the rivers and deposited at. their deltas and of the wind-blown sands which sweep over the’coastal plains. In addition there are places along the coast where the materials eroded by wave action and transported by ocean currents have accumulated in the form of recent beaches. The beaches here referred to should not be con- founded with the raised beaches, which will be discussed later in this paper. The deltas of the coast are usually unsymmetrical because of the northward direction of the coast currents. In many cases the deltas blend with the recent beaches, due to marine action. The delta of the Tumbez River, which is the northernmost of the coast, les in front of a clearly defined sea cliff. Similarly the delta of the Chira River blends with the recent sea beaches lying in front of a sea cliff, which extends from the mouth of the river northward to Negritos. The remaining rivers of the northern coastal plains do not have deltas worthy of special mention. In the extent of mountainous coast between the northern coastal plains and the south central coastal plains there are a number of localities where recent beaches may be found, and in this part of the coast the Quaternary and Tertiary deposits already described are absent. To the north of the Santa River there is an area of recent beaches in which salt is manufactured by evaporation, the brine being ob- tained by digging shallow pits, into which it filters. The area of the beaches is extensive, and the slight depth to the salt water indicates the fact that they are but slightly above sea level. The materials which have accumulated and formed the beaches have largely been brought by the Santa River and drifted northward by the ocean currents. The immediate delta of the Santa River has extended sea- ward and so connected an island with the mainland. In Chimbote and Samanco harbors one may see an area of drowned mountainous coast. At some former time the two bays were one, but the accumu- lation of sand has formed a bar and connected one of the larger islands with the mainland. The front of the raised delta of the Rimac River, on which Lima, the capital of the country, is located, has been largely cut away by marine erosion, and the currents have drifted the materials northward, forming: the spit of land called la Punta, which is a feature of the harbor of Callao. This spit is @A description of the Rimac delta by the author may be found in Bulletin No. 33 of the Corps of Engineers of Mines of Peru, published in 1905, 420 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. gradually extending, and lying between it and the island of San Lorenzo there is now a bank on which the waves break. The ultimate outcome of this process may be a connection between the mainland and San Lorenzo Island. At Port Cerro Azul the rocky promontory which protects the port was once an island. It has been connected with the mainland by the growth of the delta of the Canete River. Similarly there are a number of delta deposits and recent beaches in the southern part of the coast. In riding on a train from Mollendo along the beach before the ascent of the range of coast hills is made one may see recent con- glomerates, which have been partially eroded, and marine beaches in process of formation. The material transported by the winds has in places accumulated in areas of sand dunes which are moving with the general direction of the wind, but the more common condition is to find the sand form- ing a mantle on the hill slopes and rounding the contours of the hills, and often rising well up on to the sides and in some cases even to the crests of the mountains. The most extensive area of drifting sand is to be found in the Sechura Desert and the plains to the east of Piura. Tn the latter place the sand is held by a sparse growth of drouth- resisting trees and bushes. The height of this drifting sand as seen in the topography of the country reaches perhaps 200 feet, but proof of its great thickness was obtained when a well was drilled in it. The drillers could hardly be expected to distinguish the point at which they passed out of the wind-drifted sand, but they found nothing but sand and had no difficulty in driving the casing of the well to a depth of something over 3,000 feet. If one refers to the map of the coast of Peru and observes the con- figuration of the coast in the region of the desert of Sechura, he will see that the direction changes more to the west so that the winds blow- ing from the Pacific have a clean sweep over the desert, and the sand is carried inland by the winds in a nearly northern direction. It is this fact which accounts for the low relief near the coast where the sand has been derived and the great thickness of the Aeolian deposits to the east of Piura. In the south central coastal plains there is a conspicuous area of sand hills between Ica and Pisco; also some smaller ones to the west of Ica and Palpa. There are numerous areas of migrating sand hills in the southern coastal plains, but none of the dunes attain great alti- tudes, the surface of the plain is hard and the sand moves in crescentic dunes as over a floor. These dunes may be seen from the railway in traveling from Mollendo to Ariquipa and are one of thesights usually remembered by the traveler. Mixed with the sand which drifts over the southern coastal plains there is a large amount of white volcanic ash or sand derived from volcanic materials, GEOLOGY OF PERU—ADAMS. 421 RAISED BEACHES. The action of the sea in cutting cliffs may be well observed along the coast of the northern coastal plains, where the Tertiary forma- tions at many places rise in sheer bluffs. The same process has been in operation at other places on the coast where elevation has taken place and the cutting action of the sea is displayed in a succession of marine terraces. These are especially noticeable on the coast between Pisco and Lomas, where the Pisco formation displays approximately ten distinct terraces rising to a height of perhaps 1,000 feet. Along Top of Aill on North side of Ocofia Rivar at (ts mouth B/SO FEL. Terrace cut in igneaus rock 25007¢. Terrace covered with river bou/derae + (800f¢. 4300 Ft Yellow clay od sonastore with some bou/ders Fig. 10.—Section showing marine cut terraces at the mouth of the Ocofa River. the southern part of the Peruvian coast in front of the range of coast hills where the rivers have cut their canyons through, there are ter- races in the igneous rocks which constitute the hills and also in the remnants of what were once delta formations of these streams. The terraces at the mouth of the Ocofa River, as seen by the writer and measured with an aneroid, are represented in the following sketch (fig. 10). The upper terrace at Ocona is the highest one which was found on the coast. Terrace cut in igneous rock 405072. Sloping terrace 7So0 ft. Fic. 11.—Section showing marine cut terraces at the mouth of the Ilo River. (Compare fig. 8.) The railroad station, Tambo near Mollendo, on the Southern Rail- way, has an elevation of 1,000 feet and is situated on the north side of the River Tambo near its mouth, on an extensive terrace which must have attracted the attention of many travelers, although its origin is not explained in any scientific article which has come to the writer’s notice. The terraces south of the Ilo River, near its mouth, are indicated in the above sketch (fig. 11). 422 LHimeri Tacona ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. : 8 x 2 CY Perrros. Or Triassic Devonian OY Fic. 12.—Geologie section from Arica to La Paz, by Forbes. \\ \ re = XL gq ~ S § S § : : Q 9 5 i*) $ Alluvium Incidentally it may be said that at the mouth of the canyon just north of Pisagua in Chile similar terraces may be seen, the upper one being at an elevation of some- thing more than 1,000 feet. These terraces, taken together with the elevation at which the Pliocene Tertiary formations on the coast are found, record the rising of the land. Accordingly, the upper terraces may be Pleistocene and the lower ones Recent, but there is nothing to indicate two periods of movement, and the spacing and disposition of the terraces cut in the Pisco formation indicate a gradual elevation. GEOLOGIC SECTIONS OF THE ANDES. SECTION OF SOUTHERN PERU, ARICA TO LA PAZ, BY DAVID FORBES (1860). Tf the general section of Peru by Forbes ¢ (fig. 12) is divided so that it may be com- pared with the succession of zones parallel to the trend of the Andes, as distinguished by Steinmann at a later date, the follow- ing may be enumerated from the coast toward the interior: 1. Mesozoic sediments with interstratified porphyries of the coast range (at Arica). 2. The Tertiary (and diluvial) forma- tion of the coast plains with trachytic tuffs and ash beds. 3. The diorites of post-Cretaceous (post oolitic) age. 4. The Mesozoic sedimentaries with in- terstratified porphyries of - the western slope of the Cordilleras cut by diorites. 5. Volcanic trachytes and _ trachytic rocks of the Cordillera Occidental cutting the Mesozoic sedimentaries. 6. Zone of Paleozoic (Carboniferous and Devonian) sediments of the Titicaca basin with later “ diluvial,” including a bed of interstratified trachytic tuff. 4 Original in Quart. Journ, Geol, Soc. London, Vol, XVII, Pl. III, GEOLOGY OF PERU—ADAMS. 423 7. Zone of slates (Silurian) and granites. Comparing these zones with those enumerated by Steinmann, later to be mentioned, it will be seen that there are no granitic rocks in the coast and that the coast range which extends from Arica south- ward into Chile is not comparable with the coast range at Mollendo. In fact, there is a gap between the two just north of Arica. In other respects the zones are quite comparable excepting for the difference due to the structure of the Titicaca basin. The rocks which Forbes called “ Permian” or “ Triassic” are now called “ Cretaceous” by Steinmann, and above are included with the Mesozoic. SECTION THROUGH THE DEPARTMENT OF ANCACHS, BY RAIMONDI (1873). It should be remembered in considering this region that the Cor- dillera Occidental divides into two branches, the western known as the “ Cordillera Negra” and the eastern or principal one, the “ Cor- dillera Blanca.” Raimondi made no section, but from his writings one may recognize the following zones: 1. Granites and syenites of the coast. 2. Mesozoic sediments with porphyries and diorites. The sedi- mentaries are rare in the coast but are found more abundantly inland. 3. The diorites are seen in the Cordillera Negra and the Cordillera Blanca up to the limit of snow, but not in the crest of the range or axis. The eruption of the diorites posterior to the Jurassic removed and lifted some formations of the Cretaceous and introduced metallic veins. 4. Trachytes anterior to the present, there now being no volcanoes. These rocks are present in the Cordillera Blanca and to some extent in the Cordillera Negra but not forming peaks in the latter. Rai- mondi thinks the eruption of the trachytes occurred at a time when the two Cordilleras formed one mass and that they have since been separated by erosion. 5. In the valley of the Maranon are found older sediments, talcose slates with quartz veins which are referred to the Silurian. A small area of similar rocks was also noted at Pallasca on the western slope of the Cordillera Nevada. SECTION OF ECUADOR, BY WOLF (1892). Reviewing the geology of Ecuador as outlined by Wolf and co- ordinating the data in such a way as to compare it with the sections already given of Peru we find the following more or less distinct zones: 1. The Tertiary and Quaternary formations of the coast of marine origin. 88292—sm 1908——28 424 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 2. The Cretaceous, principally in the western Cordillera? of Ecua- dor. This rock presents three facies: (a) Toward the coast and in the hills of the coastal plains, limestones, siliceous limestones, and shales with variegated sandstones and quartzites; (0) in the moun- tain basins, sandstones, and clay shales and slates; (c) conglomerates and breccia form conglomerates, sandstones, and clay shales predomi- nating in the Cordillera. 3. With the Cretaceous are associated porphyries and greenstones, some being contemporaneous and others post-Cretaceous. With these igneous rocks, of which the diorites are the most common, are asso- ciated the mineral deposits. 4, The gneisses and crystalline schists of Archean age principally in the eastern Cordillera. There are granites in genetic relation with the gneisses and syenites in genetic relation with the schists. 5. The voleanic rocks which are related to the still active group of voleanoes of Ecuador. The volcanic tuffs contain bones of Quater- nary mammals, but the volcanic activity may have commenced in the Tertiary. 6. Lacustrine Tertiary in some of the inter-Andean basins. SECTION FROM LIMA TO CHAUCHAMAYO, BY GUSTAV STEINMANN (1904). According to Steinmann there are in Peru six zones, well marked by their distinct geologic composition, which extend parallel to the axis of the Cordilleras. These zones are designated as follows: 1. The granitic-Tertiary zone of the coast. 2. The first zone of Mesozoic sediments. 3. The zone of diorites. 4, The second zone of Mesozoic sediments with a porphyritic facies. 5. The third zone of Mesozoic sediments with a calcareous facies. 6. The zone of slates and granites. The first zone is not represented in the vicinity of Lima, but may be found to the south from Pisco to Mollendo. The granitic rocks are siluric or pre-siluric, cut by Mesozoic porphyries.?. The Tertiary formations are probably Pliocene. The second zone near Lima contains sandstones and quartzites, shales, and slates, with some limestones. The age of the formations is Cretaceous (Neocomian) as is shown by invertebrate and plant remains. The structure is in the form of an anticlinal fold. The sedimentary rocks are cut by dikes of porphyry. “ Because of the fact that the Cordilleras Oriental and Occidental in Heuador are not the equivalents of the Cordilleras Occidental and Oriental of Peru, they are here spoken of as the ‘‘ western” and ‘‘ eastern” to avoid confusion. ‘The writer wishes to suggest that the small Carboniferous area near Pisco should be included in this zone, GEOLOGY OF PERU—ADAMS. 425 In order to make clear the aspects under which the porphyries pre- sent themselves, the following explanation is offered: From the close of the Triassic, during Jurassic and Cretaceous time, a shallow sea with a gradually sinking bottom occupied the region which to-day constitutes the western part of the Andes. In this sea, in which normal sediments were being deposited, immense eruptions of basic voleanic rocks occurred, taking the forms of flows, conglomerates, breccias, sandstones, and stratified tuffs. The third, or diorite, zone is found on the western slope of the Cordillera Occidental. The diorites are clearly younger than the Cretaceous sedimentaries, since they have cut and metamorphosed them. The normal diorite contains dikes and masses of a darker, more basic, and finer-grained diorite. The Mesozoic rocks which occupied this zone have nearly all disappeared. The fourth zone includes the crest and eastern slope of the Cordil- lera Occidental. Here the porphyritic facies in the Mesozoic rocks is typical. The formations, Jurassic and Cretaceous, are strongly folded, and the inclination of the beds is more frequently to the west than to the east. In this region andesitic eruptions abound (for the most part quartzitic) and extend eastward into the next zone. The mineral deposits of the region are related to these andesites. The fifth zone in the calcareous formations gradually replaces the porphyritic facies until it becomes a great limestone formation, which, from the fossils, is shown to be of Jurassic and Cretaceous age. In the sixth zone granite and slate are found. Although no fossils have been found in the slates, they are considered to be Silurian be- cause of their resemblance to the known zone of Silurian in southern Peru and Bolivia. Below the Mesozoic sediments there is a series of dark siliceous slates and sandstones, with some conglomerates, which are believed to be Paleozoic and especially Carboniferous, the existence of Car- boniferous in the region being proven by finding a few character- istic fossils. Inasmuch as the Permian is not present in the Cordil- lera of Peru, the red sandstones and shales, with salt and gypsum, which overly the Silurian quartzites and slates, are referred to the lower Lias, no fossils having been found as yet, and they accordingly belong to the series of Mesozoic sediments. AGE OF THE CoRDILLERAS AND DEVELOPMENT OF THE SoutH AMERICAN CoNTINENT. In the atlas accompanying d’Orbigny’s monograph there is a map of South America showing the general distribution of the geologic formations according to his ideas. The map is very conventional and is of little value to-day. The most noticeable error as regards Peru is 426 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. that he breaks the continuity of the Cretaceous in the Andes between northern Peru and Ecuador, so that the Tertiary of the Pacific coast connects with the Tertiary of the Amazon basin in the latitude of the Gulf of Guayaquil. D’Orbigny also published four small maps showing the development of the South American continent. He took as a nucleus a small area of gneissic and primordial rocks along the Brazilian coast. From this area the land mass developed to the northwest. After the Carboniferous he shows a land mass in Guiana in addition to the larger one in Brazil. After the Triassic he shows an isolated land mass in the eastern Cordilleras of Peru and Bolivia, and following the Cretaceous he unites the Brazilian and Andean land masses by a fringing border of Cretaceous, and shows an isolated mass of Cretaceous in Ecuador and Colombia and Venezuela. The remaining parts of the continent were formed by the addition of Tertiary and diluvial. [The maps by d’Orbigny are of only his- torical interest as showing the development of geological science at that time. | Agassiz appears to have followed in a measure the ideas advanced by d’Orbigny. He says in substance (1868) that the valley of the Amazon was first sketched out by the elevation of two tracts of land, namely, the plateau of Guiana on the north and the central plateau of Brazil on the south. It is probable that, at the time these two tablelands were lifted above the sea level, the Andes did not exist and the ocean flowed between them through an open strait. At a later period the upheaval of the Andes took place, closing the western side of this strait and thus transformed it into a gulf open toward the east. It seems certain that at the close of the secondary age the whole Amazon basin was lined with a Cretaceous deposit, the margins of which crop out at various localities on its borders. They have been observed along its southern limits on its western outskirt along the Andes, in Venezuela along the shore line of mountains, and also in certain localities near its eastern edge. Orton evidently followed the ideas advanced by Agassiz, but his poetical and cataclastical account of the geological development of South America is of no value to science. He says, for example: “'Three times the Andes sank hundreds of feet beneath the ocean level and again were slowly brought up to their present height.” The first attempt which Raimondi made to outline the geology of Peru was in his letter to Gabb (1867). He stated that the eastern Cordillera is of greater age geologically, appearing to be composed of micaceous and talcose slates which have been metamorphosed by the elevation of the granites, that have also introduced numerous veins of quartz which in some places are quite rich in gold. The western Cordillera, he says, is made up in nearly the whole of its length of rock of much more recent age (Mesozoic). Another group GEOLOGY OF PERU—ADAMS. 42.7 of rocks, probably Carboniferous, form the great basin of Lake Titi- caca, and a small spot in the heights of Huanta. In his volume on the Department of Ancachs (1873) he elaborates his ideas somewhat more fully. He says that the first land relief produced within the limits of Peru was not the Cordillera which forms the continental divide, but the grand mountain chain which in Bolivia forms the Cordillera real and extends northward into Peru. This grand chain is formed for the most part of talcose and clay slates and owes its relief to the eruption of granitic rocks, which, however, did not always find their way to the surface, being rare in the southern part of the chain, but in many places the eruption introduced quartz veins into the slates. Contemporaneous with this relief perhaps occurred the eruption of the granites and syenites of the coast, which in many places contain thin veins of auriferous quartz. After the Jurassic began the eruption of the porphyries, and when the Cretaceous had begun the grand eruption of the diorites took place. Following the deposition of the Cretaceous the axis of the Cordillera was brought into relief. A sketch of the geology of South America was read by Steinmann before the Geological Society of America in 1891. This sketch is explanatory of a map which was prepared by him for a second edi- tion of Berghausen’s Physical Atlas. Unfortunately the map is very small, and, moreover, data were not available for an accurate map. From the sketch the following points may be gathered which are of interest here. In Devonian times, as is indicated by the sediments, there was an extensive sea embracing the larger part of South America, especially Brazil and Bolivia (and extending also into Peru). The Carboniferous deposits were more restricted, but are known from Peru, Bolivia, and Brazil. During the Permian, Triassic, and Jurassic the greater part of the South American continent was above sea level; however, the Triassic and Jurassic marine deposits have been found on the western part of the continent, rich collections of Jurassic fossils having been obtained from the Cordilleras of the Argentine, Chile, and Peru. In contrast to the small extension of marine Triassic and Jurassic the Cretaceous covers a large area, marine Cretaceous being found in all parts of the Cordillera of the Andes from Venezuela to Patagonia. The Cordillera of South America is famous for its eruptive forma- tions of the latest time, but it merits no smaller attention for its submarine eruptions during Mesozoic time and the injection of the Mesozoic strata by dioritic rocks. 498 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. BrIsuioGRAPHY. The papers mentioned in this list are referred to in the text by the dates of publication. 1814.—Humboldt, Alexander. Voyage aux régions équinoxiales du Nouveau Continent, fait en 1799-1804. Pt. I. Relation historique, Paris, 1814. Personal narrative of travels to the equinoctial regions of the New Continent during the years 1709-1804, translated by H. M. Williams, published London, 1818-19. Also translation by Thomasina Ross, in three volumes (see Vol. III), pub- lished in 1853. 1830.—Pentland, William. On the height of the perpetual snows in the Cor- dilleras in Peru. Edinburgh New Philosophical Journal, Vol. VIII, p. 311, 1830. 1835.—Pentland, J. B. On the general outline and physical configuration of the Bolivian Andes; with observations on the line of perpetual snow upon the Andes between 15° and 20° south latitude. Geogr. Soc. Journal, V, 1835, pp. 70-89. 1888.—Darwin, Charles. ‘‘ Observations of proofs of recent elevation on the coast of Chile made during the survey of His Majesty’s ship Beagle, commanded by Captain Fitzroy.” Read before the Geological Society of London and pub- lished in Proceedings, Vol. Ii, p. 446-449, 1838. (See fuller account in “ Geo- logical Observations in South America,” being the third part of the geology of the voyage of the Beagle during 1832-1836, published London, 1846. Also later editions. ) 1842.—D’Orbigny, Alcide. Voyage dans l’Amérique Méridionale, Paléontologie et Géologie. Vol. III, Pt. III, LV, 1842. 1849.—Dana, James D. United States exploring expedition during the years 1838-1842, under command of Charles Wilkes, U. S. Navy. Vol. X, Geology, published 1849. 1852.—Crosnier, L. Géologie du Pérou. Notice géologique sur les départe- ments de Huaucavelica et d’Ayacucho, Annales des Mines, Paris, 1852 (5th Ser) paviolzeide 1856.—Pissis, M. ‘‘ Recherches sur le systeme de soulévement de ’Amérique du Sud.” Annales des Mines (1856), 5™° sér., Tome IX. 1861.—Forbes, David. On the Geology of Bolivia and Southern Peru. Quart. Journ. Geol. Soc., 1861, Vol. XVII, pp. 7-62 (with geological map and sections). Also translated into Spanish by Edmundo Sologuren and published by the Sociedad Geografica de La Paz, Bolivia, 1901, with the title Geologia de Bolivia y del Sud del Pert, por David Forbes. 1861.—Salter, J. W. On the fossils from the High Andes (Bolivia) collected by David Forbes. Quart. Journ. Geol. Soc., London, 1861, Vol. XVII, pp. 62-73, pls. 4-5 (Paleozoic fossils). 1867.—Raimondi, Antonio. Letter to William Gabb. Proceedings Cal. Acad. Nat. Sci., III, 1867, pp. 359-860. Treats of geology of Peru, only part of letter published. 1868.—Agassiz, Louis. Geological Sketches. Second series, 1876. Previously published in ‘tA Journey in Brazil,” by Professor and Mrs. Agassiz, 1868. 1868.—Gabb, William. Descriptions of fossils from the clay deposits of the upper Amazon. Amer. Journ. Conchology, Vol. IV, p. 197, 1868. 1869.—Gabb, W. M. Description of new species of South American fossils. Tertiary by W. M. Gabb. American Journal of Conchology, Vol. V, part 1, p. 25, 1869. 1870.—Orton, James. The Andes and the Amazon. Harper Brothers, pub- lished 1870, GEOLOGY OF PERU—ADAMS. 429 1870.—Conrad, T. A. Description of new fossil shells from the Upper Amazon Tertiary. Amer. Journ. Conechology, Vol. VI, p. 192, 1870. 1870.— Nelson, Edward T. On the molluscan fauna of the late Tertiary of Peru. (From Zorritos, presented to Yale College in 1867 by E. P. Larkin and Prof. F. H. Bradley.) Trans. Conn. Acad. Sci., Vol. 2, p. 186, 1870. 1873.—Raimondi, Antonio. El departamento de Ancachs y sus riquezas minerales. Lima, 1878. Parte segunda: Geologia. 1874.— Conrad, T. A. Remarks on the Tertiary clays of the upper Amazon, with description of new shells. Proc. Acad. of Nat. Sci..Phila., Vol. XXVI, po 20; LST: 1876.—Agassiz, Alexander. Hydrographic sketch of Lake Titicaca. Proc. Amer. Acad. of Arts and Sci., 1876. New Series, Vol. III, p. 283. 1876.—Derby, O. A., and Agassiz, Alexander. Notice of the Paleozoic fossils (from Lake Titicaca region), with notes by Alexander Agassiz. Bull. Mus. Comp. Zoology, Harvard College, 1876, Vol. III, No. 12, pp. 276-286. 1876.—Agassiz, Alexander, and Pourtales, L. F. Recent corals from Tilibiche, Peru (now in Chile). Bull. Mus. Comp. Zool. Harvard College, Vol. III, p. 287, 1876. 1877.—Gabb, W. M. Description of a collection of fossils made by Dr. Antonio Raimondi, in Peru. Journ. Acad. Nat. Sci., Philadelphia, 1877, new series, Vol. VIII, Part III, p. 263. (Contains a synopsis of South American in- vertebrate paleontology and a bibliography of South American paleontology). 1881.—Steinmann, Gustav. Uber Tithon und Kreide in den Peruanischen Anden. Neues Jahrbuch, 1881, p. 180. 1883.—Pfliicker y Rico, L. Apuntes sobre el distrito mineral de Yauli. Anales de Const. Civiles y de Minas del Perfi, Tomo III, 1883. 1891.—Steinmann, G. ‘A sketch of the geology of South America.” Ameri- ean Naturalist, 1891, pp. 855-860. Read before the Geological Society of America Aug. 25, 1891. This sketch accompanies a map which forms a second edition of the Physical Atlas of Berghausen (Gotha Justus Perthes). Abstract and discussion, Bull. Geol. Soc. Amer., 1891, Vol. III, p. 18. Full paper in American Naturalist. ‘ 1892.— Ulrich, Arnold. Palaeozoische Versteinerungen aus Bolivien. Beilage- band. Neues Jahrbuch, Vol. VII, p. 5, 1892. 1892.—Wolf, Theodoro. Geografia y Geologia del Ecuador. Publicado por orden del Supremo Gobierno de la Repfiblica (with 2 maps). Leipzig, 1892. 1897.—Balta, José. Observaciones hechas en un viaje 4 Carabaya 1897. Bol. de la Soc. Geogr. de Lima, T. VII, Nos, 1-2-3, Vol. for 1897-8. 1897.—Gerhardt, Kk. Beitriige zur Kentniss der Kreideformation in Venezuela und Peru. Neues Jahrbuch, Beilageband XI, 1897. 1899.—Grzybowski, Josef. Die Tertiiirablagerungen des nérdlichen Peru und ihre Molluskenfauna. Neues Jahrbuch, Beilageband XII, 1899. 1899.—Balta, José. El system carbonifero en el Perfi con un mapa. La Revista Cientifica, Tomo II, Lima, 1899. 1899.—Peruvian Meteorology, Solon I. Bailey and Edward C. Pickering. Cam- bridge, 1899. Annals of the Astronomical Observatory of Harvard College (at Arequipa, Peru), vol. 39, part 1. (See Chapter II on configuration and heights of the Andes, limits of perpetual snow, ete.) 1900.—Fuchs, F. C. Nota sobre el terreno carbonifero de la peninsula de Paracas. Bol. de Minas, Tomo XVI, p. 50, Lima, 1900. 1902.—Raimondi, Antonio. El Pert. Tomo IV. Estudios mineralégicos y geologicos (primera serie), (1902), edited by José Balta. 430 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 1903.—Paulcke, W. Uber die Kreideformation in Stidamerika und ihre Bezie- hungen zu andern Gebieten. Neues Jahrbuch, Beilageband XVII. 1904.—Steinmann, Gustav. Observaciones Geolégicas de Lima 4 Chancha- mayo. Bol. del Cuerpo de Ing. de Minas del Perfi No. 12. 1906.—Steinmann, Gustav. Die Entstehung der Kupfererzlagerstitten von Coro-Coro (Bolivia). Rosenbusch Festschriften, 1906, pp. 835-368. 1906.—Dereims, Alfredo. Excursiones cientificas 1901-4. Informe del In- geniero Geologo, Alfredo Dereims, La Paz, 1906. Anexo de la Memoria de Gobierno y Fomento. 1906.—Hauthal, R. Quartare vergletscherung der Anden in Bolivien und Peru. Zeitschrift fur gletscherkunde Band I, Heft 3, p. 203, 1906. 1907.—Neumann, Richard. Beitrage zur kentniss der Kreideformation in Mittel-Peru. Neues Jahrbuch, Beilageband XXIV, 1907. Report, 1908.--, Smithsonian Smithaonian Report, 1908.-—Adams. pan VIA Limit between coast and 85 Map OF PERU, SHOWING THE CORDILLERAS OF THE ANDES. ' = = 1. = 3 _- WANIINOROO INT ovIWOHE » in ry ian as yp a. a ‘Smithsonian Report, 1908. —Adame \ ae C Ss ics x aN rs er =} AISA, See Based on Ratmonaie hap? re” 4s Sha Spe HyproLoaic MAP OF THE NORTHERN DIVISION OF THE PACIFIC SLOPE OF PERU. DEPARTMENTS OF TUMBES, PIURA, AND LAMBAYEQUE. ee a i> aie, a —_ Wirt Js a ~! sen | azo? / = aytik ¢ “ 2 * ‘ Eg shed ihe = b) J a Fapwettanaelay no Smithsonian Ri iV Vinee i ‘Smithsonian Report, 1908—Adarme. 2 PLaTe 3. ——- bese Based cn Ramondis Map HyoROLOGIC Mar OF THE NORTH CENTRAL DIVISION OF THE PACIFIC SLOPE OF PERU. DEPARTMENTS OF LIBERTAD AND ANCACHS. a ' Pas oe [> | iB ae a a =} ; j 4 vi { ; | : Vw, 7 x : ; rs af J ee : : Re a: i. ee F a a ; ae 0) ay ¥. 7 ’ soeT ner eet Cree t ne . a os lee AT ow ys ‘Smithwonian Report, 1908 —Adams, Plate 4, CERRO AZUL’ \ slur CHINCHA ALTA Bec! PA Sas a AK aN i GRP erce Del 03 — ‘Os EN AE 4 aN Fig. 5.—Lemaireocereus griseus. Fic, 6.—Opuntia streptacantha. EDIBLE FRUITS OF CACTACEA. CACTACEH OF MEXICO—SAFFORD. 543 shell. In Pereskiopsis they are covered with matted hairs or cotton. In Opuntia and Nopalea they are flat, hard, and bony, often margined and more or less ear-shaped in flat-joimted Opuntias (fig. 9°), or dis- coid and marginless, as in many cylindrical-jointed Opuntias (fig. 9°). In Cereus they are glossy black, either quite smooth or finely pitted (fig. 9°), while in Echinocereus they are covered with minute tubercles (fig. 9*). In Echinocactus they are pitted in some species and tuberculate in others. In Rhipsalis cassytha, they are kidney- shaped and finely granular. In one section of Mamillaria (Kumamil- laria) they are glossy and marked with sunken rounded pits (fig. 9*) ; in another section (Coryphantha) they are frequently smooth; while in Ariocarpus, which is quite close to Mamillaria, they are com- paratively large and tuberculate. In the little Pelecyphora asellifor- mis they are kidney-shaped, while in P. pectinata they have a peculiar boat-like form with a very large umbilicus. The seeds of nearly all Pachycerei (cardones) are used by the Indians for food. The “ higos de tetetzo” of southern Puebla (Pachycereus columna-trajaniq are a regular food staple and are to be found in the markets of Tehua- can in the month of May. CLASSIFICATION. Beginning with Pereskia, which most nearly resembles other dicotyledonous plants, and which in all probability approaches the ancestral type of the family, Schumann divides the Cactacexe into three subfamilies: (I) Pereskioidex, consisting of the single genus Pereskia; (II) Opuntioidee, composed of Opuntia and its allies; and (IIT) Cereoidezx, divided into two tribes, (1) Hchinocactew, including Cereus and its allies, E'chinocactus, Leuchtenbergia, Melocactus, Phyllocactus Epiphyllum, Hariota, and Rhipsalis; and (2) Mamil- lariew, including Mamillaria, Pelecyphora,.and Ariocarpus. With a few exceptions the genera and subgenera of Cactacee, as treated by early writers, are not sharply separated by definite limits. In many of them there are transition species which have character- istics of two genera or subgenera. Thus there are species of Echino- cactus very closely resembling certain Mamillarias (Coryphanthe) in their structure, and the relationship of several of the columnar Cerei is not clear. Various authorities have divided the old genera of Opuntia, Cereus, Echinocactus, and Mamillaria into groups, some- times regarding them as distinct genera, sometimes as subgenera, or “series.” Many of these closely allied groups differ radically from Fic. 9.—Cactus seeds. 544 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. one another, as in the structure of the seeds, yet in some cases there seem to be intermediate forms, and the flowers themselves are remark- ably similar. Notwithstanding this, it would be of great assistance to the student of Cactaceze to recognize many of the so-called subgenera as genera, not only for convenience of study, but also to show the systematic connection between the members of each group. In assign- ing the various species to a particular genus it will often be difficult to decide to which of two it belongs, but as Schumann says, this difficulty can not be avoided unless all the Cactacez be combined into a single genus Cactus.* In the following synopsis of Mexican genera, while following Schu- mann’s arrangement I shall include various genera of Opuntioide and Cereoidee established by Britton and Rose, including Pere- skiopsis and Carnegiea, and the classification of Cereus and its allies published by Mr. Alwin Berger in the Sixteenth Report of the Mis- sour! Botanical Garden, 1905, and by Britton and Rose in the Contri- butions from the United States National Herbarium, volume 12, pages 413 to 437, 1909. I have also consulted Labouret’s Monographie des Cactées (Paris, 1858); Engelmann’s Cactaceze of the Mexican Boundary, with its beautiful plates by Paulus Roetter (Washington, 1859) ; Lemaire’s delightful little handbook, Les Cactées (Paris, 1868) ; Forster’s Handbuch der Cacteenkunde, second edition (Leipsic, 1886) ; Coulter’s Botany of Western Texas (Washington, 1891-1894) and his revision of the North American Cactacee in volume 3 of the Contri- butions from the United States National Herbarium (Washington, 1894-1896) ; Schumann’s Gesammtbeschreibung der Kakteen (Neu- damm, 1899) ; and various numbers of the Monatsschift fiir Kakteen- kunde. The plates are reproductions of photographs by Mr. Guy N. Collins, Mr. C. B. Doyle, and Mr. E. L. Crandall, of the United States Department of Agriculture, Mr. T. W. Smillie, of the United States National Museum, and myself. The text-figures were drawn by Mr. Theodor Bolton, principally from photographs, and from the plates of Paulus Roetter already referred to. Synopsis oF Mexican CACTACER. I. SUBFAMILY PERESKIOIDE. The best known representative of this subfamily, which consists of the single genus Pereskia, is the Barbados gooseberry Pereskia aculeata, a scrambling shrub with long, slender branches armed with recurved prickles, and glossy green leaves, like those of a lemon. The flowers grow in clusters and are peduncled, unlike those of all @Schumann, Karl. Keys of the Monograph of Cactacex, p. 6. 1903. CACTACER OF MEXICO—SAFFORD. 545 other genera of Cactacex, in which they are sessile and solitary. The petals are pale yellow or tinged with pink, the stamens yellow, and the 5-rayed stigma white. The bracted apple-shaped fruit, as I have already stated, is used in the West Indies for tarts and sauces, like goose- berries. Pereskia tampi- cana, a species closely allied to Pereskia grandi- folia of Brazil, is a Mexi- can species, which has only been collected on the banks of the Rio Panuco, not far from Tampico, in the northern corner of Veracruz. Another species growing at Salinas Bay, on the west coast of Costa Rica, Pereskia lychnidiflora, attains the size of a small tree, and has yellowish-red flowers with petals fringed along the margin as in the genus Lychnis. Other arboreous species occur in tropical America. One of them, with long slender spines and the habit of an Osage orange, was observed by the writer in 1896 growing in hedges at Punta Arenas, Costa Rica, where it was called puipute, or ma- téare. It has since been described by Weber as Pereskia nicoyana. As- sociated with it was a columnar organo (Ce- Fie. 10.—Pereskia aculeata. \\ a reus aragoni Weber) Ww /f with edible fruit locally (\ ff known as tunas de (Zz organo. Pereskia au- \ \A— tumnalis (plate 10, fig. 2) y] £ fo 1), called manzanote in Guatemala, was col- lected by O. F. Cook, of the United States Department of Agriculture, in 1902, at El Rancho, near Zacapa, Guatemala. Excellent photographs of this species by Guy N. Collins have recently been published by Rose, in Contri- butions from the National Herbarium, volume 12, pages 399, plates 52, Fic. 11.—Pereskia lychnidiflora. 546 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. 538, 54, 1909. According to Professor Pittier the fruit is eaten by cattle during the dry season. The lens-shaped seeds have a glossy testa, which serves to distinguish this genus from the somewhat simi- lar Pereskiopsis, in which the seeds are covered with matted hairs. II. SUBFAMILY OPUNTIOIDEZ. This subfamily is distinguished by the leaf-like cotyledons of its seeds; its fleshy leaves, either broad and lasting, as in Pereskiopsis (pl. 10, fig. 2), or small, terete, and caducous, as in Opuntia and Nopalea; and by the barbed bristles, or glochidia, borne on the areoles, usually small and very numerous and mixed with soft wool. These glochidia are extremely sharp and barbed. They are loosely attached at their insertion, so that they are loosened by the slightest touch and adhere most annoyingly to the skin or clothing. In this subfamily the spine- bearing and the flower-bearing areoles are united into one circular pul- villus in the axil of the leaf. The spines occur in the lower and the bristles in the upper part of the pulvillus. Between the glochidia and surrounded by them, and always above the spines, the young shoot or flower originates (pl. 10, fig. 6). These glochidia correspond with the bristles and wool in the axils of some Eumamillaria and with the tomentum of the fioriferous areole in Coryphantha and KEchinocac- tus; but they are quite distinct morphologically from the spines themselves. They continue to grow year after year, becoming longer and more numerous, and in many species the spines themselves con- tinue to grow and increase in number.* 1. Pereskiopsis—This genus, with broad, fleshy leaves, needle- like spines, glochidia, opuntia-lke fruit, and seeds covered with matted hairs, is represented in Mexico by several species. In the vicinity of Guadalajara the fruit of Pereskiopsis aquosa (pl. 10, fig. 2) is gathered for food and sold in the markets as “tunas de agua.” It has subspatulate-elliptical, sessile, acuminate leaves, which are obscurely 5-nerved. The areoles, which are scantily provided with wool, bear at length usually a single white or grayish spine tipped with brown. The edible part of the fruit is the watery endocarp, or rind, which has an agreeable odor and taste, somewhat like that ofanapple. The seeds are margined distinctly, with the mar- gin prolonged into a kind of tail-like process extending over the funiculus, or seed stalk, and are clothed with cotton-like fiber. Conse- quently they are quite different from the smooth, glossy, lens-shaped seeds of Pereskia, and would alone serve to distinguish Pereskiopsis from that genus. Another species from the same locality is Pereskiop- sis calandriniefolia, with broad, spatulate leaves and prominent cushions of felt on the areoles, from which several long, slender, * Wngelmann, Cactaceze of the Mexican Boundary, p. 45. 1859. Smithsonian Report, 1908.—Safford. PLATE 10. Fia. 1.—Pereskia autumnalis. Fic. 2.—Pereskiopsis aquosa. Fig. 5,—Opuntia tunicata. Fic. 6.—Opuntia arizonica. LEAVES AND SPINES OF CACTACEA. CACTACEH OF MEXICO—SAFFORD. 547 needle-like brown spines protrude. This species is locally known as “alfilerillo,” or “tasajillo,” from its resemblance when leafless to the true tasajillo (Opuntia leptocaulis). Other species are the slender- stemmed Pereskiopsis spathulata, P. pititache of Tehuantepec, the very similar P. brandegeei of Lower California, P. chapistle of Oaxaca, and P. porter, the “ yellow rose” of Sinaloa. 2. Opuntia—Formerly this genus was divided into two sections; Platopuntia, including plants with flattened joints; and Cylindro- puntia, with joints cylindrical or terete. Various other classfica- tions have been proposed, the latest and most satisfactory of which is that of Britton and Rose,* who divide the genus into a number of groups which they call “series.” Among those occurring in Mexico are the following: Clavate, in which the joints are cylindrical or clubshaped and the spines unsheathed. Examples: Opuntia bulbispina, a prostrate species with spines bulbous at the base, often forming thickets in the State of Coahuila, north of Par- ras; Opuntia emory? of Chihuahua and Sonora; and Opuntia brad- tiana (Cereus bradtianus Coult.), a cereus-like erect species growing in Coahuila. Cylindracez, with compara- tively stout joints, and spines sheathed in scabbards, including the coyonostlis, or cardenches, Opuntia imbricata and O. arborescens, and the clavellinas, or abrojos, Opuntia tunicata (pl. 10, fig. 5). Monacanthe, also with sheathed spines but with slender-branched stems and a bushy habit of growth; including the tasajillos of north- ern and central Mexico Opuntia leptocaulis (fig. 12), with scarlet or coral-red fruit, and O. kleiniw, with somewhat stouter stems and vellowish fruit. An interesting feature of these plants is that the fruit is often proliferous; that is, branches and flowers frequently grow from the areoles of the cuticle covering the fruit itself. Pubescentes, with pubescent joints and sometimes without spines, though usually rich in bristles; including Opuntia rufida and O. microdasys (pl. 10, fig. 4), usually called “ nopalillos cegadores,” Vic. 12.—Tasajillo (Opuntia leptocaulis.) @Britton and Rose. A preliminary treatment of the Opuntioidee of North America. Smithsonian Misc. Coll., vol. 50, p. 508. 1908. 548 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. and O. durangensis and O>leucotricha, which bear the tunas duraz- nillos of Durango and central Mexico. Crinifere, with long wool growing from its areoles, including the nopal crinado of the State of Puebla (Opuntia pilifera). Vulgares, prostrate plants unarmed or with a few spines, includ- ing our own little prickly pear of the eastern United States (Opuntia opuntia). Subinermes, upright plants scarcely armed at all or even spineless, including the nopal de tuna Castilla (Opuntia ficus-indica), now so widely spread about the Mediterranean and in tropical America; the various varieties known as “ tunas mansas” (‘“ tame prickly pears”) in Mexico; and the tuna camuesa (0. larreyi), cultivated about Queretaro. Setispine, low plants with small joints and fine bristle-like spines, including Opuntia filipendula and O. setispina of Texas and Chihuahua. Tune, bushy plants, often with abundant yellow spines, including the common prickly pear of Texas and Tamaulipas (0. lindheimer?), the cuija (QO. cuija) of northern and central Mexico, and O. tuna of the West Indies and gardens of Mexico, with edible red fruit and yellow or red flowers. Fulvispinosee, bushy or spreading plants with brown or partly brown spines and fleshy fruits, including nopal de raiz of the Alvarez Mountains (0. megarrhiza), O. engelmanni of northern Mexico and Texas, and O. arizonica (pl. 10, figs. 3 and 6). Albispinose, robust plants with white spines and broad petals, including the tuna cardona (Opuntia streptacantha) of San Luis Potosi, from which such enormous quantities of “tuna cheese” are made. Stenopetale, large white-spined plants with narrow petals, includ- ing Opuntia stenopetala, which was first collected on the battlefield of Buena Vista, south of Saltillo, Coahuila. The flowers of Opuntia (pl. 10, fig. 3) are for the most part yellow or orange, but in some species they are rose colored or crimson. One of the loveliest is the rose-colored flower of Opuntia basilaris of the southwestern United States. In all cases the perianth opens widely and the stamens are not so long as the petals. These features serve to distinguish the Opuntia from the closely allied genus Nopalea. The fruit (“tuna”) of many species and varieties of Opuntia (pl. 9, fig. 6) is edible and is an important food staple. The young, tender mucilaginous pads are cut into strips (“nopalillos ”) and cooked like string beans, and the pads (“ pencas”) are also extensively used as @See Griffiths, David, and Hare, R. F. The Tuna as food for man. U. S. Dept..Agr., Bur. Plant Industry Bul. 116. 1907. CACTACEH OF MEXICO—SAFFORD. 549 food for cattle in arid regions. The rigid, sharp spines with which most species are armed (pl. 10, fig. 6) is a serious drawback in feeding them to cattle, but these are frequently removed by singeing the pads with a torch. Efforts have been made to propagate spineless forms, and these have in many cases been successful.¢ 3. Nopalea—tThis genus is closely allied to Opuntia, but it may easily be distinguished by its flowers, the perianth of which is erect instead of widely spreading, and the stamens are longer than the petals, though they are exceeded by the style. The most important species of this genus is Vopalea coccinellifera, the “ nocheznopalli ” on which the cochineal insect is reared. The flower is of a beautiful rose color or crimson. The fruit is edible, but is inferior to most of the Opuinta fruits sold in the Mexican markets. The plants are usually more or less tree like, growing to a height of 3 or 4 me- ters, with the trunk and older branches cylindrical or nearly so. The younger parts are flat and green, the joints oblong or ovate and compressed, usually spineless when young, and bearing small, fleshy ca- ducous leaves like those of Opuntia, but sometimes becoming spiny when SEZ older. ‘This plant was Fic. 13.—Opuntia flower, Fic. 14.—Nopalea extensively cultivated by vertical section. flower. the Mexicans before the discovery of America, for the sake of the dye-yielding insect which feeds upon it. Its cultivation was after- wards introduced into Guatemala, Honduras, the Canary Islands, Algeria, Java, and Australia. In recent years cochineal has largely been supplanted by aniline dyes, and its cultivation has been dis- continued in nearly every place but the Canary Islands. The prin- cipal sources of its supply were formerly the states of Guerrero and Oaxaca. Other species of the genus growing in Mexico are Vopalea dejecta (called nopal chamacuero, at Victoria, Tamaulipas), which has narrowly oblong joints armed with whitish spines, and 1. kar- winskiana, which grows in the vicinity of Colima, on the Pacific coast. It is probably this species which grows about Guadalajara, “See Griffiths, David. The Prickly Pear as a farm crop. U. S. Dept. Agr., Bur. Plant Industry Bull. 124. 1908. 550 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. in the State of Jalisco, Where it is called “nopalillo de flor.” A new species (V. guatemalensis) with linear reflexed leaves and very spiny areoles was recently described by Doctor Rose from specimens collected in Guatemala by Mr. William R. Maxon, of the United States National Museum. According to Professor Pittier, who ob- tained flowers and spines of this species at Zacapa, it is locally known as tuna lengua-de-vaca, or “ cow’s-tongue prickly pear.” Figure 14, page 449, was made from Professor Pittier’s photograph.¢ III. SUBFAMILY CEREOIDEZX. In this group there are no glochidia, the spines are never barbed, and the leaves are reduced to scales often so minute as to be invisible to the naked eye. The ovules are not covered by the expanded funic- uli; the seeds, instead of being bony and ivory colored, as in the Opuntioideex, have dark, thin, glossy shells, either quite smooth, or pitted, or covered with wartlike tubercles; and the cotyledons, instead of being leaflike, as in the Opuntioides, are more or less globose. Schumann divides this subfamily into two tribes: (1) Hchinocac- tc, including Cereus and its allies, Echinopsis, Echinocactus, Leuch- tenbergia, and Melocactus, forming the subtribe Armatw@, which is characterized in general by stout, spiny stems; and Phyllocactus, Epiphyllum, Hariota, and Rhipsalis, forming the subtribe /nar- mate, with spineless and leaflike or slender cordlike stems; and (2) Mamillariew, including Mamillaria and its allies, Pelecyphora and Ariocarpus. In most of the Echinocactee the flowers are tubular and the ovary and fruit either scaly or covered with little tufts of wool from which spines issue. In Rhipsalis, however, the flowers are wheel shaped. The fruits of some species of the Cereus group are unarmed, while in Cactus (Melocactus) the smooth, red, club-shaped fruit resembles the “chilitos” of a Mamillaria. Areoles, or pulvilli, as they are sometimes called, are composed of two parts, aculeiferous, or spine bearing, and floriferous, or flower bearing. In Kchinocactus these are either united into a single areole or are separated by a short groove (as in E'chinocactus scheerii). In E'chinocereus the flower or young bud bursts through the epidermis above and close to the spiniferous areole. On the other hand, in some divisions of Mamil- laria the spine-bearing and flower-bearing areoles are quite separate, the flowers appearing to spring from between the tubercles of the plant (pl. 9, fig. 1), while in the subgenus (or genus Coryphantha the two areoles are joined by a long groove, and the flowers, growing from the nascent or very young tubercles, appear to spring from the apex of the plant (pl. 14, fig. 3) very much as in the group of the “See Rose, J. N. Nopalea guatemalensis, a new cactus from Guatemala. In Smithsonian Misc, Collections, vol, 50, p. 380. 1907. CACTACEH OF MEXICO—SAFFORD. 551 tubercled Echinocacti to which #. hewaedrophorus (pl. 13, fig. 3) and E. scheerti (pl. 3, fig. 3) belong.* Tribe Echinocactee. 1. Cereus and its allies—The plants which have been grouped to- gether under this name vary considerably in the characters of their flowers and fruit. They naturally form several distinct divisions which have been regarded by various authors as subgenera, or, in a few cases, as genera. Among the most recent authorities to treat of the group are Britton and Rose, who have established a number of new genera and have raised the giant sahuaro, or suguaro, of our southwestern deserts into a monotypic genus, named Carnegiea,? after Mr. Andrew Carnegie, to whose generosity the Desert Laboratory of the Carnegie Institution owes its existence. The most important studies of the genus thus far have been those of Mr. Alwin Berger, published in the Sixteenth Report of the Missouri Botanical Garden, 1905, and Britton and Rose in volume 12 of Contributions from the National Herbarium, pages 413 to 487, 1909. From the classification of Berger and from Britton and Rose I take the following list of genera: Cereus, as understood by Britton and Rose, includes Cereus hewxa- gonus (usually called C. peruvianus) and C. jamacaru, night-flower- ing cacti with columnar upright, branching, ribbed, fluted, or angled stems and branches, and beautiful white flowers with numerous sta- mens and many-rayed stigma. Though of South American origin these species are now widely spread in the West Indies, the first also in Central America and tropical Mexico. Rathbunia, named by Britton and Rose in honor of Dr. Richard Rathbun, Assistant Secretary of the Smithsonian Institution in charge of the U. S. National Museum, includes several species in- digenous to the coast of Western Mexico, among them Rathbunia alamosensis (Cereus alamosensis Coulter), a plant with sharp irregu- lar ribs, brown velvety areoles, stout spines, and bright salmon-colored trumpet-shaped day-blooming flowers, first collected by Doctor Pal- mer, near Alamos, southern Sonora. Nyctocereus, the type of which, Vyctocereus serpentinus, called junco espinoso in the State of Jalisco, is often seen in collections. This species has straggling cylindrical fluted stems and branches with numerous areoles bearing a tuft of white wool and weak radiating “Engelmann, George. Cactacez of the Mexican Boundary, p. 46. 1859. >Britton, N. L., and Rose, J. N. A New Genus of Cactaces. Journ. New York Bot. Garden, vol. 9, p. 185. 1908. ; ; ¢See Coville, Frederick V., and MacDougal, D. T., “‘ Desert Botanical Labora- tory of the Carnegie Institution,” Publication No. 6 of the Carnegie Institution of Washington. 88292—sm 1908——386 502 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. bristle-like spines. The targe white flowers are night blooming, and the fruit contains a few large seeds imbedded in red pulp. Cephalocereus, in which the flower-bearing portion is differentiated from the rest in the form of a woolly head, or cephalium, near the apex of the stem, either symmetrical and terminal or one-sided. The fruit (fig. 16), covered with a bare skin becomes shriveled with age. Examples: Cephalocereus senilis, the cabeza de viejo, or old man’s head, of the limestone cliffs of Hidalgo, Guanajuato, and Puebla; C. cometes, of San Luis Potosi; and C. palmeri (“organo”), of Victoria, \ Tamaulipas. Lophocereus, in which the stem and branches are ribbed very much as in Myrtillocactus, and the are- oles are remote on the sterile portions but crowded on the flower-bearing branches, and on the latter produce short white wool and long stiff bristles. Example: Lophocereus schottii, the sina or sinita (old-man cactus) of Sonora and Lower California. Myrtillocactus, which may be recognized by its short trunk, bluish- green branches curving upward, with six ribs, which form a starlike cross section and are armed with stout dagger-like spines, usually with a stout laterally compressed central and 5 radials about its base. Example: Mvyrtillocactus geometrizans (pl. 11, fig. 1) which yields the small fruit called “ oarambullas.” Pachycereus includes several giant cardones of the Pacific coast region, among them P. pringlei and P. pecten-aboriginum. The first of these may be recognized by the little spheres of yel- lowish tomentum with which its fruit is cov- ered (fig. 17); the second by its spiny fruit, resembling great chestnut burs, which the In- eee, : " al iT wu --— iS. E #® 2 Fig. 1.—Mamillaria conoidea. Fic. 2.—Mamillaria longimamma. FIG. 5.—Pelecyphora pectinata Fic. 6.—Peleeyphora aselliformis (enlarged 6 diameters). (slightly reduced). TYPES OF MAMILLARIA AND PELECYPHORA. Smithsonian Report, 1908.—Safford. - PLATE 15. Fic. 2.—Ariocarpus furfuraceus, ARIOCARPUS RETUSUS AND ARIOCARPUS FURFURACEUS. CACTACEH OF MEXICO—SAFFORD. 563 closely allied Mamillaria.¢ At the apex of the tubercles there is a more or less distinct wool-bearing areole. The flowers appear from near the center of the plant, springing from the midst of a tuft of wool. They are white or delicately rose tinted, with the petals marked by a median stripe. The ovary and fruit are naked, the seeds comparatively large and tuberculated.? Among the species thus far known to science are Ariocarpus fissu- ratus, sometimes called the “living rock,” with the surface of the tubercles grooved and warty; A. kotschubeyanus (pl. 3, fig. 4), called pezuna de venado, with rose-colored flowers, and small delta-shaped tubercles marked by a median longitudinal groove; A. retusus, or “ cobbler’s thumb ” (pl. 15, fig. 1), with sharp pyramidal tubercles (sometimes called A. prismaticus) ; and A. furfuraceus (pl. 15, fig. 2), with abruptly acuminate triangular tubercles, sold for medicinal pur- poses in Mexican markets under the name of “ chautle.” On plate 5, figure 1, is shown the photograph of a plant collected by the writer on the slope of the Cerro de Perote, near Parras Coahuila. It is either A. fissuratus, or a new species very closely related to it. My guide called it “ chautle;” but as I now picture it, lying like a gray stone on the hillside of Perote, I call it “ living rock.” *See Thompson, C. H. Missouri Bot. Garden Rep., vol. 9, p. 128. 1898. > Coulter, J. M. Contr. from U. S. Nat. Herb., vol. 3, p. 128. 1894. ANGLER FISHES: THEIR KINDS AND WAYS. By THEODORE GILL. If I should begin but to name the several sorts of strange fish . . . that run into the sea, I might beget wonder in you, or unbelief, or both; and yet I will-venture to tell you.... Izaak Walton (apropos of the Common Angler), Compleat Angler, chap. 19. GENERALITIES. It is generally assumed that the capture of fishes by means of a lure originated only when man had acquired a certain stage of intel- ligence, but, countless myriads of years before man was born, the art had been developed among animals of a much lower class—fishes themselves. Such animals are still existent and manifest under con- siderable variety and in many species. The largest and best known of the kind is the common fish especially known as the “ angler.” This name was first used for it by Thomas Pennant in 1776, and has proved to be very acceptable to most persons, but it is not entirely applicable to the fish. The word angle is primarily connected with the curved hook which is the chief agent in the capture of a fish, but the angler fish has no hook. It has a rod and a bait, but it needs no hook, for the bait attracts a victim sufficiently near to be seized upon by a sudden leap of the angler. The advantage is thus given by kindly nature to the ever-ready fish. No renewal of the bait is necessary, for the angler does not wait till the approaching little fish has time to nibble; no elaborate preparation of rod, line, hook, and bait are needed, for the fish is always prepared; not time and labor, such as taking the capture off the hook, carrying it a long distance, and various details of making ready for eating, are required, for all such actions are rendered unnecessary by the capac- ity to take and ingest in one continuous process. The angler, so named by Pennant and so called by all ichthyolo- gists since, is the only one of its kind frequenting the shallow seas of northern Europe and northern America, but it is only one of a numerous group. ‘That group, however, is represented by species 565 566 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. inhabiting the deep seas-of almost all parts of the globe, as well as by numerous species lurking in tropical coral groves, and in the sargasso meadows of the high seas. The group is distinguished by so many peculiar characters that it is ranked as an order or sub- order by all modern ichthyologists under the name of Pediculati or Pediculates. The name is primarily due to Cuvier, who gave the form Acauthopterygiens a pectorales pédiculées, or, for short, Pec- Fic. 1.—The common Angler (Lophius piscatorius). After Smitt. torales pédiculées as a family designation. This was latinized as Pediculati and subsequently used as a subordinal and still later as an ordinal term. With the last sense it is here used. The old authors mostly associated with the Pediculates, the Batrachoidids, or Toad- fishes, and they have been restored to the order by Regan (1909), but not by other authors, nor in the present article. ANGLER FISHES—GILL. 567 PART T. Orper PEDICULATI. The Pediculates are teleost fishes, offshoots from the Acanthopteryg- ians, or spine-finned fishes, and have a closed air bladder, if any, the scapular arch connected with the sides of the skull, the mesoco- racoid bone absent, the actinosts in reduced number (2 or 3) and in typical form elongated to form false arms, or pseudobrachia, and the \! Fig, 2.—Shoulder girdle of the Angler, showing the pseudobrachium or false arm with its two actinosts (a), the hypercoracoid (hr), hypocoracoid (ho), and postscapula (ps), as well as proscapula or ccenosteon (c). After Mettenheimer. ventrals advanced forward; the ventrals, when present, are indeed jugular; the skull is depressed and without a myodome or cavity for the insertion of the ocular muscles, the parietals are separate and thrown to the sides by the intervention and contact of the supraoc- cipital and frontals, and the suborbital chain of bones is absent. The vertebral centra are well developed and separate, but there are neither ribs nor epipleurals. The branchial apertures are much reduced and manifest as foramina in or about the axils of the pectorals, generally the upper axils, sometimes the lower. 88292—sm 1908——37 568 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Fishes having these characters in common exhibit great diversity in other respects, and not least in the provision for alluring other fishes. They have, however, been mainly associated on account of agreement in other characters. The most essential of these are the position of the branchial apertures, the direction of the mouth, whether opening upward or downward, the number of bones (actinosts) in the false arms (pseudobrachia) that bear the pectoral fins, the development of the first dorsal, and the presence or absence of ventral fins. ‘There are six groups which are so trenchantly distinguished by modifications or combinations of these characters as to have secured from ichthyolo- gists family designations. Their mutual relations may be best exhibited in a synoptical table: PEDICULATE FAMILIES. I. Branchial apertures about (in or behind) the inferior axils of the pectorals ; opercular bones moderately or little developed. (a) False arms with 2 actinosts; pectorals scarcely geniculated ; body depressed; hypapophyses appressed (Lophioidea) Lophiida. (b) False arms with 8 actinosts; pectorals strongly geniculated ; body compressed or tumid; hypapohyses erect (Antennaroidea) Antennariide. 2. Ventrals lost. (Ceratioided.) (a) Mouth large, directed upward; snout flat behind and rostral SPINGXCLEC by sae sa eae es ee Ceratiida. (b) Mouth large, directed downward; snout procurrent and rostral tentaclervat endsandshorizontal =o Gigantactinide. (c) Mouth small, terminal, and nearly horizontal; snout blunt and desuituteiottentacd. Aoerratiide. Il. Branechial apertures about superior axiis of pectorals; opercular bones greatly developed; ventrals developed; false arms with 2 actinosts; mouth inferior; rostral tentacle inferior or terminal, sometimes atrophied (Ogco- CGephnaloid ca Wess ee ee ee ee ee Ogcocephalide. Almost all the Pediculates have the foremost spine advanced for- ward near or on the snout and modified to serve as a lure for other fishes; it has beeri likened to an angler’s rod with its line and bait, and this fancy has been carried out in the names given to the apparatus. S. J. Garman, in his fine work on “The fishes” of A. Agassiz’s Reports of an Exploration off the West Coast of Mexico, etc. (1899), has designated as the “illictum” or “bait and rod” the foremost dorsal spine with its leaflike appendage, and further distinguished the “bait ” as the “esca.” These are developed with various modi- fications in the Pediculates that live in the shallow or less deep seas, and undoubtedly the illicium and esca actually serve as a rod and bait, but, of course, the fish so provided does not knowingly act as an angler, for its action is merely automatic. The modification of the spine doubtless originated in a fortuitous manner and its use to the ANGLER FISHES—GILL. 569 fish was such that it, and its progeny so favored, survived the “ strug- gle for existence ” and, through the slight useful modifications super- vening, the specialized illicium and esca of the modern fishes became perfected. But this was not all. Some stout-bodied Pediculates resorted to deep and deeper waters, where the light from the sun was faint or even ceased, and a wonder- ful provision was at last developed by kindly nature which replaced the sun’s rays by some reflected from the fish itself. In fact the illicium has developed into a rod with a bulb having a phosphorescent terminal portion and the “ bait ” round it has been also modified and variously added to; the fish has also had superadded to its fishing apparatus a lantern (lampas) and wormlike lures galore. How efficient such an apparatus must be in the dark depths where these angler fishes dwell may‘be judged from the fact that special laws have been enacted in some countries against the use of torches and other lights for night fishing because of their deadly attractiveness. Not only the curiosity of the little deep-sea fishes but their appetite is appealed to by the wormlike objects close to or in relief against the phosphorescent bulb of the anglers. Only a few of the many varieties of the torch-bearing anglers need be noticed here. They all occur in the family of deep-sea Pediculates known as the “ Ceratiids.” Generally the interspinal bone is directed forward and mostly con- cealed, and the articulating spine or rod extends upward; the termi- nal portion of the spine is provided with a bulbiform apparatus, with a luminiferous terminal surface and various appendages in relief against it. Often the appendages are curiously developed, sometimes filiform and simple, as in Ceratias ; sometimes papilliform and numer- ous, as in Melanocetus. Occasionally the rod is very stout and the wormlike appendages numerous and manifest on the rod as well as around the bulb; in the imantolophi of the Atlantic and Pacific (Japan) the furniture is carried to an extreme. Rarely the interspinal bone appears to be exserted and prolonged and the spine or rod articulated a long distance from the back, as in Mancalias. A few other Pediculates (the Gigantactis is the only one known) with a slender body developed in another direction. The illicium and snout conjoined extended far forward in a horizontal direction. All the Pediculates till now considered have the first dorsal spine really dorsal, or at least rostral. Now we may take notice of some that reverse the usual order of nature. This reversal is manifested in the family of Ogcocephalids (better known as Malthids). Not uncommon along the southern coasts are certain fishes of this family, inhabiting shallow waters with a sandy bottom. They are of toad-like appearance, and rest on their arms as a toad does on its hind legs, while the fins are far in advance and assume the function of fore 570 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. feet. Though like toads, the fishes are generally known to the people not only as “ toads ” but also as “ sea bats” on account of the appear- ance they present in the water, and this name has been perpetuated in the scientific designation of the longest known species—the J/althe vespertilio. The reversal in the attitude and position of the members, whereby what are usually the fore limbs become the hind and the hind limbs the foremost, is not the only case of contrariety. The dorsal has become lowermost and by a remarkable growth. The anterior spine had advanced forward on the snout; then the forehead had grown out into a long projection which forced the snout with the dorsal spine downward, thus reversing its direction. Still more, the dorsal spine—spine only in name, however—had lost, or perhaps never developed, the function of rod and line, and has apparently assumed a tactile function. It has a papilliform tip, and doubtless by means of it feels for its food. The few species of J/althe and one of Halieutwa are the only repre- sentatives of the family that are inhabitants of the shallow waters. There are many other species, but they are deep-water forms. The Malthids, indeed, are a numerous family of deep-loving fishes, and every expedition for the exploration of the deep sea brings back new forms. These exhibit considerable difference in the develop- ment of the subrostral or rostral tentacle, and in some the tentacle is obsolete. None, however, have the tentacle developed as in Malthe, and no others have the projecting forehead or the downward trend of the tentacle. In all others the rostral cavity is open forward, and perhaps the tentacle may serve as a lure, as in the Pediculates gener- ally. That it is not a very efficient organ is apparently indicated by its obsolescence in some of the species. One remarkable characteristic of the Pediculates, so far as known, is the provision made for the eggs. The oviposition of only two species is known, it is true, but those two being of widely distinct families—the Lophiids and Antennariids—it is probable that what is true for them is true for all others of the same families. The two species in question are the common angler (Lophius piscatorius) and the frog-fish (Pterophryne histrio). These agree in having paired ovaries in which are developed eggs so connected that, when emitted, they are enveloped in a glutinous secretion reflecting the form and structure of the ovaries but, on contact with the water, become im- mensely distended and form buoyant raft-like receptacles which float at or near the surface till the eggs are hatched. The rafts are swollen to an enormous size in comparison with the mother fishes, those of the common angler sometimes reaching a length of 36 feet and those of the frog-fish a couple of feet. Whether the Pediculates of other families agree with the Lophiids and Antennariids is doubtful and a subject for future investigation. ANGLER FISHES—GILL. 571 A most remarkable episode is connected with the history of the Antennarids. In 1872 the illustrious Professor Agassiz obtained a globular mass of sea-weed (Sargassum) charged with eggs, and as- sumed that the mass was a nest made by a frog-fish, and for a gene- <= ES Fic. 3.—Ovaries of the common Angler (Lophius piscatorius). After Fulton (reduced). ration or more his view was unhesitatingly adopted. It was only after the discovery of the actual oviposition of the frog-fish that sus- picion was attached to the old identification. As will appear from the third part of this article, the Sargassum conglomeration is due to the peculiar eggs of a flying-fish. Fic. 4.—Enlarged view of ovaries and ova of the common Angler (Lophius piscatorius). After Fulton. The Sladenia is especially noteworthy as being a less depressed form than others of its family as well as on account of the difference in the connection of the spines and rays. Earuty PEpicuLatess. It might naturally be supposed that fishes so eccentric in their organization as the Pediculates came into existence at a compara- tively late period in the development of animal life. It is there- Dae ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. fore remarkable that typical representatives of the order have left evidences of earlier existence than most modern types. Near the commencement of the Tertiary epoch, in the sea which then covered an area which is now surmounted by Mount Bolca in northern Italy, an Antennariid laid wait for its prey, which consisted largely of animals very different from any now living. So closely related, indeed, was that Antennariid to living forms that it can scarcely be distinguished generically from the species of Pterophryne, which is now represented in almost all tropical and subtropical and even temperate seas where the sargasso weed flourishes or is carried by currents and winds; its relationship and characteristics were, how- ever, long misunderstood, and consequently it was isolated as a peculiar generic type—/Histionotophorus—without knowledge of its relationship or distinctive characters. Contemporary with the An- tennariid, as well as a cotenant of the same sea, was an angler that Wie. 5.—Skeleton of the Angler (Lophius piscatorius). After Agassiz. no one has ever attempted to differentiate generically from the common angler (Lophius piscatorius) of the present northern At- lantic;* Lophius brachysomus is the universally accepted name of the Eocene angler. Tue FamiInirs oF PEDICULATES. THE LOPHIIDS. The Lophioid family is represented by the largest and best known of the Pediculates, the angler of the books, better known to the shoremen of the New England States as the “ goose fish ” and to those of old England as the “fishing frog,” “sea devil,”.and by “Tt is not intended to deny that the fossil Lophiid may be generically dis- tinct from the Lophius piscatorius, for it probably was, but the generic char- acters of the modern forms are mostly osteological and not evident superficially. It may be that the Eocene species was more related to Lophiomus or even con- generic with it, for apparently it had a reduced number of vertebra. ANGLER FISHES—GILL. 573 various other designations. It has been described at length by the present writer in “ The life his- tory of the angler,” published in 1905 in the Smithsonian Miscellaneous Collections (vol. XLvII, pp. 500-506, pls. Lxxim-— Lxxv.). Three genera were then noticed, Lophius, Lophiomus, and Lophiodes * or Chirolophius. Since then a remarkable form (Sladenia) has been described by C. Tate Regan from the In- dian Ocean (“Chagos Relating to this, see Nathorst, A. G.: Emanuel Swedenborg som geolog. Geol. Féren. i Stockh. Forh., vol. 28 (1906). ¢Pehr Kalm’s Wistgotha och Bohuslindska resa f6rréttad ar 1742. Stock- holm, 1746. @The layers cited by Linné correspond to the following strata (compare G. Holm: Kinnekulle. S. G. U., ser. C, No. 172, Stockholm, 1901), according to the nomenelature now prevailing: (a) The Sandstone Cliff=the sandstone layer. (b) The Limestone Wall=the layer of alum slate. Linné was the first (Holm, loe. cit.) to notice the occurrence of flint. (c) The Redstone Cliff. The green “slate-pencil stone,’ or “ griffelsten,” which according to Linné is the undermost layer of this cliff is, according to Holm, the lower graptolite shales. Linné’s ‘‘ Potstone” is the Orthoceras lime- CARL VON LINNE AS A GEOLOGIST—_NATHORST. 133 This last-mentioned statement that the “ highest hill” consisted of sandstone, * * * is palpably a slip of the pen and should be graystone, because only a few pages farther on in the latter it is said: The uppermost hill consisted entirely of graystone covered with soil. * * * * * * *k oS % % The most remarkable part of the description, in which he goes into a detailed account of his opinion in the matter, reads as follows: The strata terre everywhere around Mésseberg, Alleberg, and Billingen are all like those of Kinnekulle, so that when one exactly knows the rock layers of Kinnekulle, one also knows what may be found all over in the depths. + * * These strata extend even farther; * * * thus the profile of Kinnekulle may serve as a clew to the strata terre or anatomy of the earth’s crust, not only here in Westrogothia, but perhaps of the greater part of the world. Lithogenesy is a simple enough matter, although still quite obscure owing to the few researches as yet made. We know that the sand of the sea becomes sandstone, the compounds of the sediment of the sea clay, the clay becomes lime, the lime ‘“ blecke” [chloride of lime], the “ blecke”’ chalk, and the chalk silex or flint. Peatbog mud becomes slate and the slate again surface soil. We see that spar, quartz, and rock flint, together with mica, are formed where the rocks have cracked and join them together. We see that graystone is formed from loose friable material. * * * * * * The statements made in the last paragraph but one open up at once a conception of a uniform succession of strata all over the globe, and in so doing lay the foundation for stratigraphic geology and the knowledge of the history of the earth in complete accord with the words often cited by Linné, “ that the stones shall speak for themselves.” It should be emphasized right here that Linné nowhere mentions anything about the strata underlying the sandstone layer of the * ok of stone, but supposedly owing to an error in the writing Linné states that the undermost stratum of this is gray, instead of red. There are, of course, actually four divisions of the Orthoceras limestone, which, according to color and succession (from below upward), are distinguished as the lower red, lower gray, upper red, and upper gray. (d) The Gorstone Cliff=the upper gray Orthoceras limestones. (Holm, loc. cit.) ; (e) High Hills, where Linné did not notice any bedrock exposure but only loose blocks, must be considered as corresponding to strata which are now called the Chasmops limestone, Trinucleus shales, and Brachiopod shales. (f) The Crow Mountain=the upper graptolite shales. (g) The Highest Hill=the diabase cover (trap). It is thus only the Ceratopyge limestone, between the alum and the lower graptolite shales, and the three strata just mentioned (the Chasmops limestone, the Trinucleus, and the Brachiopod shales) that Linné did not observe. When it is taken into consideration that he stayed in this place but three days, and that he also made a number of botanical and other observations and notes, it must be admitted that he made good use of his time. * * #* 734 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. - Westrogothia Mountains, and in the Curiositas Naturalis he comes right to the point, “ but what then follows (i. e., below the sand- stone) I do not know.” His opinion of the formation of rock strata at the bottom of the sea is briefly set forth in the 1748 edition of the Systema Nature, and the following year (1749) he published an account agreeing with the former, although somewhat more detailed, in the introduction to the Giconomia Nature. He assumed that the sargassum or sargasso weed floating on the sea had been of con- siderable importance in this respect, by quieting the motion of the WIVES 4. aay ta In the Sargasso are found species of birds and fishes; that is, those who have floating eggs and species of Vermes, Cochlez, Conch, Corals, Medusx, etc., other than those known on the shores. These gradually die off and then their bodies sink and mix with the clay, when thus mixed with clay, being themselves covered with limeshells, they change the clay into limestone.% This might serve to explain why such petrifications, Orthoceratites and others, the animals of which are now entirely unknown to us, have been found in the lime rocks of the “allvar” of Oland. Kinnekulle seems to indicate similar conditions, and the latter may have originated through the conglomera- tion of sea sand forming its undermost layer of sandstone, on which rests the slate formed by the black mud or ooze covering the sand of the sea bottom. On top of the last named there is a deep stratum of sandstone full of strange fossils, perchance precipitated through the action of the Sargasso. Upon this last-mentioned layer there is again slate originating from molded Sargasso, and the uppermost part is gray rock formed of gravel, which may be identical with that cast up by the sea when the rock first became a shore line. It is strange that the uppermost strata of all the mountains consist solely of graystone. From this it may be concluded that they [the strata of gray- stone] have not been there from the beginning, because the stratum next below is slate, which is always formed from black mold; and as all mold is formed from yegetable growth, there must have been plants before the graystone layer got there, and hence it could not have been created.2 Those who would at- tribute all this to the deluge think very little and see still less. A much jonger period than the duration of the fiood has been required for this. That the “trap ” of the Westrogothia mountains could be accounted for in no other way than did Linné, and Swedenborg before him, is not to be wondered at, as nothing was known at that time either of the enormous streams of lava poured out in violent volcanic erup- tions or of horizontal intrusions between the strata. * x * * * * x Linné stated his view of a definite succession of strata throughout the world in the twelfth edition of the Systema Nature, the third part of which, treating of the mineral kingdom, was issued in 1768. ko The fact that Linné’s opinions about the Strata telluris were pub- lished in the Systema Naturz caused them to become widely known @See Syst. Nat., sixth ed., p. 219, note 5. 6 Reisen durch Westgothland, p. 35. i se a ee cee ee Pe ee ; ; ‘ J CARL VON LINNE AS A GEOLOGIST—-NATHORST. 735 and accessible to the entire scientific world. This fact makes it at once evident that they could not have been without influence on the development of geological science, and, as I have previously pointed out in my work, Jordens Historia, Werner was doubtless influenced by them. This influence seems to have been partly direct and partly conveyed through Torbern Bergman’s Physical Description of the Globe, the first edition of which appeared in 1768 and the second in 1773-1774. The opinion of Linné, quoted in that work, as to the formation of the rock strata from marine sedimentary deposits, was revised by himself and is identical with the one we have become acquainted with above. But Bergman built still higher on the foundation laid by Linné, and he recognized the fact that below the stratified rocks there were what he called the “ primitive” or “ primeval,” or what we now term the “Archean” rock. He further brought the loose earth strata together as a separate group, “ flung together ” or “ piled up ” rocks, and in addition treated the volcanoes as a distinct type. The constructive work of geology as a science was thus quite essentially improved and enlarged upon, and through the efforts of the German, A. G. Werner, its framework may be said to have reached its first completion, as the latter divided the stratified rocks into two principal groups, 1. e., metamorphic rocks and sedi- mentary rocks, each with several subdivisions. Werner has generally been considered the founder of the science of geology, and his merits as such are in no degree diminished by the circumstance that he constructed his system on the foundation laid by Linné and Bergman, a fact which he himself would surely have been the first to admit. If it be asked whether he was aware of the works of the Swedish investigators, the answer would be that he not only knew them, but that he himself had quoted them extensively. ik tk Ee * rf - Oe * * * * §. Haughton, the English geologist, who naturally can not be suspected of partiality in either direction, also says that— he [Werner] seemed to have obtained his idea of dividing the rock species according to their order of succession through a study of Linné’s work, but he further elaborated this idea in supposing that each different rock species had been deposited during a gfinite period.@ Tt is quite evident that in order to be able justly to determine the value of a discoverer’s contribution to science, the position of that particular science during the period of his activity must, as has here @Samuel Haughton, Manual of Geology, second edition, London, 1866, p. 128. In this work “the celebrated Linné” is cited as the first who knew how to assign a certain age to each group of rock species. (This is perhaps somewhat exaggerated). There is further an account of what Linné says in the Systema Nature concerning the order of succession and origin of the rock species. 736 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. been done, be taken into consideration. If, on the other hand, we look at Linné’s arrangement of the strata terre from the point of view of our present knowledge of them, it certainly appears very defective and incomplete, as it only embraces the Cambrian and Silurian strata, and hence only an inconsiderable part of the entire succession. But the same remark may be made, and has also been made, against Werner’s arrangement, i. e., that even the latter was too incomplete. * * * Lainné’s classification, which was founded on the conditions in Sweden, could apply to no other than Swedish sedimentary deposits. Werner, on his part, founded his classification on the conditions obtaining in Erzgebirge and adjoining parts of Saxony and Bohemia,? and hence also within a relatively limited region. The general conditions at the time of the establishment of Linné’s, as well as of Werner’s, systems were consequently such that neither could be complete. * * * Each [material structure] requires a firm foundation, and it was Linné who laid the first foundation stone of the science of stratigraphic geology, after whom first Bergman and then Werner continued to build. And through the work of Werner, to complete the parable, the structure reached such a height that it commenced to attract general attention. BALSBERG AND OTHER STRATA OF SKANE BELONGING TO THE CRETA- cEous PEriop—* * *—-PRESENTIMENT AS TO THE LENGTH OF GEOLOGICAL TIME. During his journey in Skane, Linné had an opportunity to study the local Mesozoic strata, partly those belonging to the Cretaceous system and, in northwestern Skane, partly those belonging to the Lias proper. In accounting for these it may perhaps be most con- venient to * * commence with the rock species now called testaceous lime or shell stone. * * * Beneath all this was the mountain itself, which was a loose rock of a pale yellowish lime. This limestone lay nearly hori- zontally, with a horizontal cleavage, and for the most part it was so friable that it could be pulverized between the fingers, although farther down it was somewhat firmer than above. The species of rock is rather rare in Sweden, with the exception of Skane, but more common in Germany and Spain. Most of the walls in the city of Cadiz are built of this rock species. When this stone is examined closely it is found that it consists entirely of shell gravel, mussels, periwinkles, corals, or of such gravel as is thrown together in sub- ’ “Xx, A. vy. Zittel, ‘‘ Geschichte der Geologie” und “ Paliiontologie bis Ende des 19. Jahrhunderts,” p. 90. Miinchen und Leipzig, 1899. CARL VON LINNE AS A GEOLOGIST—NATHORST. . Tah marine channels and in some places on the shores, so that this entire lime rock is nothing but a cemetery of as many dead animals as there are grains in drift sand. * * * When we now further consider how so many strange animals have come to be buried here, animals that are now scarcely to be seen in Europe, we meet with a new argument which also requires considerable reflection. The Testacez or all the genera of mussels that live on the sea bottom, are divided into the Littoralia and Pelagica. Shell collectors call those mussels and shell animals Littorales which do not live in the deep, but only keep close to the shore, so that their shells are cast up on the shores as soon as they die and perish. Hence these shells are common in natural-history collections. On the other hand, Pelagiei are those shell animals that exist in the depths of the sea and never come near the shores, a reason why their shells are very difficult to obtain. The depths of the sea are mostly barren and covered with sand or corals, with few fishes and little fauna or flora, for where there are no plants there are few of the worms and fishes which live on them. Thus there is but one plant that can grow at the greatest depths, and that is the Sargasso, of which greater quantities are found than of any other plant in the world. It floats on the water and sticks together, so that the sea at a distance resembles a green meadow, and under this are to be found the strangest creatures and mussels, or Testacea pelagica, which, as they successively grow up and die, drop their shells on the bottom and fill it up. Most of the Testacea in the mountain we have mentioned are the Pelagica, and they must have originated where the Sargasso grew, but how they have come to be in this place is a harder problem to solve. Most people say that the shells have been brought hither in the deluge, and that hence they were witnesses of this wonderful alteration of the earth. But those who say so seem to me to be very little at home in mathematics, for how could the surging waters have thrown the shells a distance of several thousand miles to a certain place and then place above them the other earth strata in such regular order? If these phe- nomena are sufficiently considered one must necessarily admit that the earth must have been covered by the sea, and that Sargasso must have grown here under which these creatures lived and died, where- upon finally, after the water had been reduced and the Sargasso driven away, gravel must have been cast up by the waves in new ridges on the shore and then coalesced into stone. * * * Be * * % * * * As has been stated above, little was known at the time in question concerning the deep-sea fauna or of the manner in which shells, mussels, and other animals are distributed on the sea bottom, and * * * ‘it is not to be wondered at that Linné, who in this respect 738 . ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. was forced to rely on others, should have supposed that the shell- gravel lime (testaceous lime) was formed at great depths and was chiefly derived from pelagic forms. This rock species, as we now know, is in reality a shore formation, even if shells of pelagic forms be embedded in it. * * * * * * After having observed at Helsingborg the shifting strata of siliceous shales and shaly sandstone contained in the high blutf east of the town * * * Lainné writes: My mind reels when, on this height, I look down on the long ages that have flowed by like waves in the sound and have left traces of the ancient world, traces so nearly obscured that they can only whisper now that everything else has been silenced. These words are evidences of inspiration, and it may easily be seen that if Linné had drawn his conclusions entirely from his own observations in nature, he would certainly have become a champion of the belief that those geological events of which “ the stones speak ” had, contrary to the prevailing opinion on the subject, required a tremendously long period of time. * * * Fossits or Dirrerent Kinps—BELEMNITES—TRILOBITES—PLACE OF THE TRILOBITES IN THE ZOOLOGICAL SYSTEM—GRAPTOLITES—INCLU- SIONS IN AMBER. In addition to scattered notes of a paleontological nature in his travel descriptions Linné has also, aside from his already quoted work, Corallia Baltica, left descriptions of fossils, partly in the Systema Nature, partly in the Museum Tessinianum, and also in a special paper in the Vetenskapsakademiens Handlingar, 1759. * * * * % * % In the Museum Tessinianum Linné gives a fairly correct state- ment of the different ways in which fossils may occur. He char- acterizes four different groups as follows: 1. “ Fossils (Fossilia),” such corals and shellfish as have lain in the ground for a long time nearly unchanged [a large part of what we now call “ subfossils,” but also others]. 2. “ Filled-up petrifactions (redintegrata)” of creatures covered with a hard shell. Upon being embedded in the earth and after the dissolution of the soft parts the cavity was filled with a sediment which has hardened into stone and which is now surrounded by the shell. These are the most common, and are found particularly in lime and chalk. 3. “ Impressions (impressa)” of animals embedded in the sediment and “imprinted as in moldings.” After the animal is dissolved only the impression is left. Examples: Impressions of fishes in the shales, sometimes also in sandstone. CARL VON LINNE AS A GEOLOGIST—NATHORST. 739 4. “ Petrifactions, perfect transsubstantiata of the interior as well as the exterior shape.” Such are most fossil trees, but also “ Hn- trochia and Asteriw columnares” (i. e., stalked crinoids, which is saying too much for them). * * * Of the fossils described I shall only mention one or two of the Swedish ones. The Belemnites are thus characterized: The stone is somewhat cylindrical, but cone-shaped, and may be split length- wise into two equal parts. It appears to have been bored through longitudinally with a coarse groove, from which numerous stone filaments extend laterally. All whole specimens have a conical depression at the root. This does not appear to be true of the filled-up petrifactions, but of the unaltered fossils, and particularly to those that are most often found loose, with none of the inclosing matrix. In the Systema Nature (twelfth edition) it is added that the cavity at the base occasionally contains a conical nucleus [the phrag- macone|, divided by partitions in the same manner as the Nautilus, and having at its side a siphon, a fact demonstrating that even in this instance Linné attentively followed up discoveries made abroad. His description of the brachiopod Pentamerus conchidium (Helm- intholithus conchidium L.), commonly occurring on Gotland, is also of interest. He calls it the “ cloven shell,” and says: We find no more than a single shell at a time, and never a pair, as is com- mon in mussels. It seems strange that when we strike it with a hammer it always splits longitudinally into two equal parts. 3k % Cy *% *% * Undoubtedly, however, the most interesting fossil in the Tessinian collection was the complete specimen of the trilobite named by Linné “Entomolithus paradoxus,” a species to which Al. Brongniart later gave the name “Paradowides tessini.” WUinné’s Swedish name for it was “understone” or “ wormstone of water fleas,” and his descrip- tion of it is as follows: In this collection there is a species of stone from the alum pit at Dimbo in Westrogothia the like of which scarcely exists in the world. It is a pure black slate stone, as large as the whole of this (folio) page, most plainly engraved. The body is oval, anteriorly blunt and laterally divided by more than 20 folds, with as many pairs of feet at the sides, of which the hindfeet are the longest. In general form this worm seems to resemble most closely the species named “J/onoculus,”’ although of a kind quite unknown to us. * = * No stone nowadays keeps the naturalist more busy than this one, which is daily being collected and examined, particularly by the English, so that the diligent researches of several men may some day result in ascertaining its orgin. * * * The figure given by Linné was rather coarsely executed (“figura nimis rudis,” Dalman says), wherefore it has caused later investigators some trouble. Linné says that the reproduction is almost of natural size, while, to be more exact, the size of the figure 740 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. is about two-thirds of the original. The specimen is in the mineralog- ical museum of the University of Copenhagen, but according to a statement of Prof. N. V. Ussing it is said to be in a poor state of preservation and seems to be gradually approaching destruc- tione A et eee *k *£ *% * * % % During his journey in Skane, Linné noticed in the aluminous shales at Andrarum the /nsectorum vestigia, already described from that place by Bromell, in which the former recognized animals of the same group he had previously observed in Oland and Westrogothia, “ although there as large as a fist, but here in Andrarum not larger than flies.” The trilobite in question, named in the Systema Nature “ Entomolithus paradoxus B Cantharidium,” is the Olenus truncatus. On the other hand, he found it difficult to determine the “ Vermicu- lorum vaginipennium imagines,” also occurring in this place and cited by Bromell, which, however, he later recognized as belonging to the same animal group, and introduced in the Systema Nature as “Kntom. parad. y Pisiformis,” or what we now call the “Agnostus pisiformis.” In the Vetenskapsakademiens Handlingar, 1759, Linné contrib- uted a special paper, accompanied with illustrations, on the fossil Entomolithus paradowus, in which he included all trilobites. * * * Two of these need not arrest our attention; they are pygidia of Calymmene punctata and C. blumenbachui (according to Wahlenberg and Dalman), while the third is the most interesting. Linné says of it that it “is one of the most perfect specimens I have been able to find among many thousand fragments,” and, further, after having described the thoracic shield and the somatic segments, the lateral parts of which [pleure] “are not feet, but an outgrowth of the shields proper,” he says: The most peculiar feature of this specimen is, first of all, the antenns, which we have never seen in any other, and which most plainly demonstrate that this fossil must belong to the insect genus (to which at that time the Crustacea were referred), or, to be more exact, a genus intermediate between Cancros, Monocu- los, and Oniscos. * * * While it is true that the specimen described by Linné, which is usually considered to be the Parabolina spinulosa, and at all events is an olenid, has been mentioned since that time by several of those who have investigated the trilobites, it seems that there has been a gen- erally indifferent or skeptical attitude concerning the antenne pointed out by Linné. When toward the end of the last century it was shown by American scientists that the trilobites actually possessed antenne, S. L. Tornquist called attention to Linné’s observation, and on this subject there arose a discussion between the former and C. E. Beecher, the American geologist, who pretended not to see a trace of antenne CARL VON LINNE AS A GEOLOGIST—NATHORST. 741 in the impressions described by Linné,* while, on the contrary, Térn- quist continues to regard them as such. In the present status of the question a definite decision is impracticable unless the specimen de- scribed by Linné can be recovered. However, Linné’s surmise that these animals possessed antenne has, at any rate, been confirmed, and it was he who first assigned to the trilobites their true position in the zoological system of that day. During his journey in Skane Linné also observed graptolites, and in the description of his travels gives an illustration of them. * * * They are introduced into the Systema Nature (1768) as Graptolithus scalaris, and have since served as a type of the genus. According to S. A. Tullberg,’ the vertical form shown in the figure is what is now termed the “ Climacograptus scalaris,” while the one spirally coiled is probably the Wonograptus triangularis. * * * Although Aristotle, Pliny, and Tacitus had, on the whole, a true conception of the formation of amber, diverging opinions were later expressed by Agricola (1546) and others, who believed that it had been formed in the sea. During the journey in Skane Linné noticed amber in several places, but especially at Falsterbo. * * * In the Museum Tessinianum the following is said of amber: In it are often found several insects, the presence of which shows that the amber has been floating and has always been above the surface of the earth (i. e., not formed in the sea). Beetles with shells on their wings are rarely found in it. In the Systema Nature it is said that the insects were incased at a time when the amber was resin or gum, and that they are not true fossils. As a conclusion to this chapter I may appropriately quote Linné’s own words on the subjects which have here been dwelt upon: Of what use are the great numbers of petrifactions, of different species, shape, and form which are dug up by the naturalists? Perhaps the collection of such specimens is sheer vanity and inquisitiveness. I do not presume to say; but we find in our mountains the rarest animals, shells, mussels, and corals em- balmed in stone, as it were, living specimens of which are now being sought in vain throughout Europe. These stones alone whisper in the midst of general Silence. * * #* * = * * * * * The infinite number of fossils of strange and unknown animals buried in the rock strata beneath the highest mountains, animals that no man of our age has beheld, are the only evidence of the inhabitants of our ancient earth at a period too remote for any historian to trace. 7S. L. Térnquist, “On the appendages of trilobites,” Geological Magazine, 1896, p. 142, and Linné “On the appendage of trilobites,” ibid., p. 568. C. E. Beecher, ““On a supposed discovery of the antenne of trilobites by Linné in 1759,” American Geologist, Vol. 17 (1896), p. 308. oS. A. Tullberg, ‘“‘On the graptolites described by Hisinger and the older Swedish authors,” Bihang till K. Sv. Vet. Akad. Handl., Vol. 6, No. 18. Stock- holm, 1882. 742 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. SUMMARY. As will be seen from the above account Linné’s contributions to geological science were both many sided and extensive. In assuming the existence of a definite succession of strata throughout the world he laid a foundation for stratigraphic geology which has been en- larged by Werner and other geologists of subsequent times. Linné certainly did not have, and at that period could not have had any true conception of the relative age of the other sedimentary rock species as compared with those of the Westrogothia Mountains; but this was a problem for investigators of a later period to solve. It is very interesting to notice how it gradually dawned upon him that the fossils in the Silurian strata, which he at first believed to exist in the depths of neighboring seas, were probably for the most part extinct; and the same may also be said of certain Cretaceous fossils. This circumstance seemed so remarkable to him because of the fact that at that time there existed no adequate conception of the real age of the earth. Linné, who in so many things was far ahead of his own time, seems even in this respect to have been inclined to emancipate him- self from the prevailing opinion, and, as has been stated above, it was only his conviction that the Bible should be literally interpreted that prevented him from adopting a more liberal view. On the other hand, he strongly opposed the prevalent belief that the evidences of a former higher water level which were so common in Sweden, were connected with the “ deluge.” On the contrary he declares that he has never seen a trace of that catastrophe. The evidences cited by him in support of this higher water level of ancient times, which are founded on his own observations, are clear and positive, * * * and he was the first naturalist to de- scribe shore lines in the high mountains. He always took special pains to collect data on material of economic importance, and hence also labored within the realm of applied or practical geology. It should here be remembered that although he pointed out the significance of mar] in the agricultural development of Skane, he was so far ahead of his time that a hundred years passed by before his prophecy commenced to attain its fulfillment. * * * He left a clear and concise statement of the different ways in which fossils may occur; he published an excellent description, for its time, of Gotland’s fossil corals; he was the first to assign to the trilobites their true position in the zoological system of the period, and in the Museum Tessinianum and the Systema Nature he de- scribed a great number of fossils, many of which still retain the spe- cific names assigned to them by him. [ee ee ee eee SO ee ee a eee a ee hie > De CARL VON LINNE AS A GEOLOGIST—NATHORST. 743 Linné’s contributions to the sciences of geology and paleontology were consequently of such a nature and extent that each alone would have secured him a respected scientific name. These have long been overlooked because of the fact that, in spite of their great intrinsic importance, they were overshadowed by the magnificent achievements that linked his name with the biological sciences, and because of the additional fact that geology at his time did not exist as an inde- pendent science. What we have now seen, however, seems to demon- state that even geology has every reason to appreciate what Linné has done and accomplished as one of the founders of this science. 88292—sm 1908S——48 | Poa nt) vie Smithsonian Report, 1908.—Thompson, PLATE 1. WILLIAM THOMSON, BARON KELVIN OF LARGS. THE KELVIN LECTURE:* THE LIFE AND WORK OF LORD KELVIN.? (With 1 plate.) [Delivered April 30, 1908. Abridged by request and revised for the Smithsonian Insti- tution April 6, 1909.] By Prof. Sirvanus P. THompson, D. Se., F. R. S., Past President of the Institution of Electrical Engineers. On the 17th of December, 1907, aged 83 years, died William Thomson, Baron Kelvin of Largs. Adequately to set forth the life and work of a man who so early won and who for so long maintained a foremost place in the ranks of science were a task that is frankly impossible. The greatness of a man of such commanding abilities and such profound influence can not rightly be gauged by his contemporaries, however intimately they may have known him. But if by the very circumstance that we have lived so near to him we are debarred from rightly estimating his greatness, we at least have the advantage over posterity that we have been able to speak with him fact to face, to learn at first hand his modes of thought, to sit at his feet as students or disciples, to marvel at his strokes of genius achieved before our very eyes, to learn to love him for his single-hearted enthusiasms, for his kindliness of soul, his unaffected simplicity of life. But if we may not attempt the impossible, we may at least essay the task of setting down in simple fashion some account of those things which he achieved. Let me first set down in briefest outline a sketch of his early life. William Thomson was born on June 26, 1824, in Belfast, being the second son and fourth child of James and Margaret Thomson. James Thomson, who was at that time professor of mathematics in 4Founded by the Institution of Electrical Engineers (of Great Britain) in memory of the work of the Right Hon. Lord Kelvin, O. M., G. C. V. O., F. R. S., and of his connection with the institution as president in 1874, in 1889, and in 1907. > Reprinted, by permission, from Journal of the Institution of Electrical Engineers, London, vol. 41, 1908, pp. 401-428. - 745 746 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the Royal Academic Institute of Belfast, was the son of a small farmer at Ballynahinch, in County Down, where his ancestors had settled about the year 1641 when they migrated from the lowlands of Scotland. James Thomson had early shown a taste for mathe- matical studies, and by study of books had mastered the art of mak- ing sundials. He had then been sent to a small school in the district to learn classics and mathematics, risimg while still a youth to the position of assistant teacher. During the winters he followed the courses in the University of Glasgow, crossing back to Belfast for the summers to resume teaching at school. After thus attending Glasgow University for five years he was appointed professor of mathematics in 1815 at the Belfast Academic Institute. His eldest son, James (Lord Kelvin’s elder brother), was born in 1822, and Wilham (Lord Kelvin), as already stated, in 1824. In 1830, when William was 6 years old, his mother died. His father would never send his boys to school, but taught them himself. In 1832, when William was 8 years old, Professor Thomson was offered the chair of mathematics at Glasgow, and he with his family of six children accordingly removed from Belfast. He was in many ways a remark- able man. He made several original contributions to mathematics and produced several sound text-books, including one on the differ- ential and integral calculus. But his range of accomplishments was wide. He was an excellent classical scholar, familiar with both Latin and Greek, and able, on occasion, to give lectures in the classics to the university students. After his removal to Glasgow he still kept the education of his sons in his own hands, and so it happened that in 1884 William Thomson, when in his eleventh year, matricu- lated as a student in the university without ever having been at school. He early made his mark by his progress in mathematics and physical science, and in 1840 produced an essay “ On the figure of the earth,” which won him the university medal. He also read Greek plays with Lushington, and moral philosophy. To the end of his life he was in the habit of bringing out quotations from the classic authors. His fifth year as a student at Glasgow (1839-40) was notable for the impulse toward physics which he received from the lectures of Prof. J. P. Nichol and from those of David Thomson (a relation of Faraday), who temporarily took the classes in natural philosophy during the illness of Professor Meikleham. In this year William Thomson had systematically studied the Mécanique An- alytique of Lagrange and the Mécanique Celeste of Laplace, both mathematical works of a high order, and had made the acquaint- ance—a notable event in his career—of that remarkable book, Fou- rier’s Théorie de la Chaleur. On May 1 he borrowed it from the college library. In a fortnight he had read it completely through. LIFE AND WORK OF LORD KELVIN—THOMPSON. 747 The effect of reading Fourier dominated his whole career thence- forward. He took the book with him for further study during a three months’ visit to Germany. During his last year (1840-41) at Glasgow he communicated to the Cambridge Mathematical Journal, under the signature “ P. Q. R.,” an original paper “On Fourier’s expansions of functions in trigonometrical series,’ which was a defense of Fourier’s deductions against some strictures of Professor Kelland. He left Glasgow University after six years of study, without even taking his degree, and on April 6, 1841, entered as a student at St. Peter’s College, Cambridge. Here he speedily made his mark, and continued to contribute, at first anonymously, to the Cambridge Mathematical Journal, papers inspired by his studies of the higher mathematics and by his love for physics. The analogy between the movement of heat in conductors along lines of flow and across surfaces of unequal temperature, and the distribution of elec- tricity on conductors in such a way that the lines of electric force were crossed orthogonally by surfaces of equipotential, led to his paper entitled “ The uniform motion of heat in homogeneous solid bodies, and its connection with the mathematical theory of elec- tricity.” Here was an undergraduate of 17 handling methods of difficult integration readily and with mastery, at an age when most mathematical students are being assiduously drilled in so-called “ geometrical conics ” and other dull and foolish devices for calculus dodging. It is true he followed the courses of coaching prescribed by his tutor, Hopkins, but he could not be kept to the routine of book work and he never quite forgave Hopkins for keeping from him until the last day of his residence at Cambridge Green’s rare and remark- able Essay on the Application of Mathematical Analysis to the Theories of Electricity and Magnetism. He also formed a close friendship with Stokes, then a young tutor, with whom, until his death in 1902, he maintained a continual interchange of ideas and suggestions in mathematical physics. Of Thomson’s Cambridge career so much has been written of late that it may be very briefly touched here. How he went up for his Tripos in 1845; how he came out second wrangler only, being beaten by the rapid Parkinson; how he beat Parkinson in the Smith’s prize competition; how he rowed for his college to save Peterhouse from being bumped by Caius in the university races of 1843; how he won the Colquohoun silver sculls; how he helped to found the Cambridge University Musical Society and played the French horn in the little orchestra, which at its first concert, on December 8, 1843, performed Haydn’s First Symphony, the Overture to Masaniello, the Overture to Semiramide, the Royal Trish Quadrilles, and the Elizabethen Waltzes of Strauss! But these things—are they not written in the book of the Cambridge Chronicle? 748 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. Once when Lord Kelvin was in a chatty mood I asked him point- blank how it occurred that he was not senior wrangler. His blue eyes hghted up as he proceeded to explain that Parkinson had won principally on the exercises of the first two days, which were devoted to text-book work rather than to problems requiring analytical inves- tigation. And then he added, almost ruefully, “I might have made up on the last two days but for my bad generalship. One paper was really a paper that I ought to have walked through, but I did very badly by my bad generalship, and must have got hardly any marks. I spent nearly all the time on one particular problem that interested me, about a spinning top being let fall on to a rigid plane—a very simple problem if I had tackled it in the right way—but I got in- volved and lost time on it and wrote something that was not good, and there was no time left for the other questions. I could have walked over the paper. A very good man Parkinson—I didn’t know him personally at the time—who had devoted himself to learning how to answer well in examinations, while I had had, during pre- vious months, my head in some other subjects not much examined upon—theory of heat, flow of heat between isothermal surfaces, dependence of flow on previous state, and all the things I was learn- ing from Fourier.” And then he drifted off into a talk of his early papers, and to the mathematical inference (as the result of assigning negative values to the time ¢) that there must have been a creation. “Tt was,” he continued, “this argument from Fourier that made me think that there must have been a beginning. All mathematical con- tinuity points to a beginning—this is why I stick to atoms * * * and they must have been small—smallness is a necessity of the com- plexity. They may have all been created as they were, complexity and all, as they are now. But we know they have a past. Trace back the past and one comes to a beginning, to a time zero beyond which the values are impossible. It’s all in Fourier.” On leaving Cambridge Thomson went to Paris and worked in the laboratory of Regnault at the College de France. He was here four months. There was no arrangement for systematic instruction, and Thomson’s principal occupation was to work the air pump to make a vacuum in one of two large glass globes which Regnault was weigh- ing against one another in some determinations of the densities of gases. He made here the acquaintance of Biot and of Sturm and Foucault, of whom he spoke in terms of admiration. Returning, he was awarded a college fellowship of £200 a year. Thomson was now 21 years old, but had already established for himself a growing reputation for ce mastery of mathematical phys- ics. He had published about a dozen original papers, and had gained experience in three universities. In 1846 the chair of natural LIFE AND WORK OF LORD KELVIN—THOMPSON. 749 philosophy at Glasgow became vacant by the death of Professor Meikleham, and Thomson, at the age of 22, was chosen to fill it. His father, Prof. James Thomson—he died in 1849—still held the chair ef mathematics, Prof. Thomas Thomson held that of chemistry, while Prof. Allen Thomson occupied the chair of anatomy. William Thomson was the youngest of the five Professors Thomson then holding office in Glasgow. He chose for the subject of his inaugural lecture: “On the distribution of heat through the earth.” This professorship he continued to hold till he resigned it in 1899, after continuous service of fifty-three years. Of his work as a university teacher this is hardly the occasion to say much; it will be fully described by his pupil and successor, Prof. Andrew Gray. The old college buildings where he lectured and worked for twenty- four years were ill-adapted for any laboratory facilities, yet he contrived to organize a physics laboratory—the first of its kind in Great Britain—in some disused rooms in a dark corner of one of the quadrangles, and enlisted the voluntary service of a number of keen students in his early experimental researches on the electrodynamic and thermoelectric properties of matter. In the lecture theater his manifest enthusiasms won for him the love and respect of all stu- dents, even those who were hopelessly unable to follow his frequent flights into the more abstruse realms of mathematical physics. Over the earnest students of natural philosophy he exercised an influence little short of inspiration, an influence which extended gradually far beyond the bounds of his own university. The next few years were times of strenuous work, fruitful in results. By the end of 1850, when he was 26 years of age, he had published no fewer than 50 original papers, mostly highly mathe- matical in character, and several of them in French. Among these researches there is a remarkable group which originated in his attendance in 1847 at the meeting of the British Association. He had prepared for reading at that meeting a paper on the exceedingly elegant process discovered by himself of treating certain problems of electrostatics by the method of electric images, a method even now not sufficiently well appreciated. But a more important event was the commencement of his friendship with Joule, whom he met here for the first time. Joule, a Manchester brewer, and honorary secre- tary of the Manchester Literary and Philosophical Society, had for several years been pursuing his researches on the relations between heat, electricity, and mechanical work. Incited at first by Sturgeon into investigations on the electromagnet, and on the performance ec electromagnetic engines—that is, electric motors—Joule had alreac in 1840, communicated to the Royal Society a paper on the “* duction of heat by voltaic electricity.” He had also read pap: 750 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. the British Association’s meetings “ On the electric origin of chem- ical heat,” at Manchester, in 1842; “On the calorific effects of mag- neto-electricity ” and “ On the mechanical value of heat,” at Cork, in 1843; “On specific heat,” at York, in 1844; and “On the mechanical equivalent of heat,” at Cambridge, in 1845. But at that date, when there was as yet no doctrine of conservation of energy, when scien- tific men were not accustomed to distinguish either in language or in fact between force and work, when “caloric” was classed with light and sound among the “imponderables,” Joule’s work was listened to with impatience, and his teachings fell upon deaf ears. Was he not an amateur, dabbling in science, and carried away with strange notions? For the Oxford meeting, too, Joule had prepared a paper. Its title was “On the mechanical equivalent of heat, as determined from the heat evolved by the agitation of liquids.” It was relegated to an unimportant place, and would have received as little notice as its predecessors but for Thomson’s intervention. Thomson, in fact, though he at first had some difficulty in grasping the significance of the matter, threw himself heart and soul into the new and strange doctrines that heat and work were mutually con- vertible, and for the next six or eight years, partly in cooperation with Joule, partly independently, he set his unique powers of mind to unravel those mutual relations. Thomson’s mind was essentially metrical. He was never satisfied with any phenomenon until it should have been brought into the stage where numerical accuracy could be determined. He must measure, he must weigh, in order that he might go on to calculate. “T often say,” * he once remarked, “ that when you can measure what you are speaking about and express it in numbers, you know something about it; but when you can not measure it, when you can not express it in numbers, your knowledge is of a meager and unsatis- factory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of sczence, what- ever the matter may be. * * * The first step toward numerical reckoning of properties of matter, more advanced than the mere ref- erence to a set of numbered standards, as in the mineralogist’s scale of hardness, or to an arbitrary trade standard, as in the Birmingham wire-gauge, is the discovery of a continuously varying action of some kind and the means of observing it definitely and measuring it in. terms of some arbitrary unit or scale division. But more is neces- sary to complete the science of measurement in any department, and iat, isthe fixing on something absolutely definite as the unit of Tecture on “ BHlectrical units of measurements” at Institution of Civil seers, May 3, 1883. Reprinted in Popular Lectures and Addresses, Vol. I, LIFE AND WORK OF LORD KELVIN—THOMPSON. "51 reckoning.” It was in this spirit that Thomson approached the sub- ject of the transformation of heat. Joule had laid down on certain lines the equivalence of heat and work, and had even measured the numerical value of the equivalent. But before him, in 1824, Carnot, though he proceeded on the fallacious assumption of the material nature of caloric, had, in his remarkable book, Réflexions sur la puis- sance Motrice du Feu, discussed the proportion in which heat is convertible into work, and had introduced the very valuable notion of submitting a body to a reversible cycle of operations such that, after having experienced a certain number of transformations it is brought back identically to its primitive physical state as to den- sity, temperature, and molecular constitution. He argued, correctly, that on the conclusion of the cycle it must contain the same quan- tity of heat as that which it initially possessed. But he argued, quite incorrectly, that the total quantity of heat lost by the body during one set of operations must be precisely compensated by its receiving back an equal quantity of heat in the other set of opera- tions. We can see now that this is false; for if it were true, none of the heat concerned in the cycle would be transformed into work. Those who were investigating the subject at this time, among them Clausius and Rankine, perceived this, and noted that since the steam received into the cylinder must be hotter than that ex- pelled from it, the degree to which the transformation is success- ful must depend on the respective temperatures; a fact, moreover, recognized by all engineers since the date when Watt discovered the advantage of cooling the exhaust steam by a condenser. Carnot, indeed, proved that the ratio of the work done by a perfect—that is, a reversible—engine to the heat received from the source depends on the temperatures of source and condenser only; and when these temperatures are nearly equal the efficiency is expressible by the product of their difference into a certain function of either of them, called “ Carnot’s function.” Rankine went further in pointing out that this function was greater as the temperature in question was lower. But here Thomson’s exact mind seized upon the missing essential. Temperatures had hitherto been measured by arbitrary scales based on the expansion of quicksilver, or of air or other gas; and the quicksilver thermometer scale did not agree precisely with that of the air thermometer. He was not satisfied with arbitrary scales. He had this in hand even before his first meeting with Joule, and in June, 1848, communicated to the Cambridge Philosophical Society a paper “On an absolute thermometric scale founded on Carnot’s theory of the motive power of heat, and calculated from Regnault’s observations.” In this paper he set himself to answer the question, Is there any principle on which an absolute thermo- 752 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. metric scale can be founded? He arrived at the answer that such a scale is obtained in terms of Carnot’s theory, each degree being de- termined by the performance of equal quantities of work in letting one unit of heat be transformed in being let down through that difference of temperature. This indicates as the absolute zero of temperature the point which would be marked as — 273° on the air- thermometer scale. In 1849 he elaborated this matter in a further paper on “ Carnot’s theory,” and tabulated the values of “ Carnot’s function ” from 1° C. to 231° C. Joule, writing to Thomson in De- cember, 1848, suggested that probably the values of “ Carnot’s fune- tion” would turn out to be the reciprocal of the absolute tempera- tures as measured on a perfect gas thermometer, a conclusion inde- pendently enunciated by Clausius in February, 1850. Independently of Joule, Mayer and Helmholtz had been considering the same prob- lems from a more general standpoint. Helmholtz’s famous publica- tion of 1847, Die Erhaltung der Kraft—On the Conservation of Force (meaning what we now term “ energy ”’) was chiefly concerned with the proposition, based on the denial of the possibility of per- petual motion, that in all the transformations of energy the sum total of the energies in the universe remains constant. Thomson continued to work at the subject. He experimented on the heat developed by compression of air. He verified the singular prediction of his brother, Prof. James Thomson, of the lowering by pressure of the melting-point of ice. He gave a thermodynamic ex- planation of the nonscalding property of steam issuing from a high- pressure boiler. He formulated, in the years 1851 to 1854, with scien- tific precision, in a long communication to the Royal Society of Edin- burgh, the two great laws of thermodynamics—(1) the law of equiva- lence discovered by Joule, and (2) the law of transformation, which he generously attributed to Carnot and Clausius. Clausius, indeed, had done little more than put into mathematical language the equa- tion of the Carnot cycle, corrected by the arbitrary substitution of the reciprocal of the absolute temperature; but Thomson never was grudging of the fame of independent discoverers. “ Questions of personal priority,” he wrote, “ however interesting they may be to the persons concerned, sink into insignificance in the prospect of any gain of deeper insight into the secrets of nature.”* He gave a demon- stration of the second law, founding it upon the axiom that it is im- possible, by means of inanimate material agency, to derive mechanical effect from any portion of matter by cooling it below the temperature of the coldest of the surrounding objects. Further, by a most ingen- lous use of the integrating factor to solve the differential equation for the quantity of heat needed to alter the volume and temperature “Presidential address, Brit. Ass., 1871, and Popular Lectures, Vol. II, p. 166. LIFE AND WORK OF LORD KELVIN—THOMPSON. 158 of unit mass of the working substance, he gave precise mathematica] proof of the theorem that the efficiency of the perfect engine working between given temperatures is inversely proportional to the absolute temperature. In collaboration with Joule he worked at the “ Ther- mal effects of fluids in motion,” the results appearing between the years 1852 and 1862 in a series of four papers in the Philosophical Transactions, and four others in the Proceedings of the Royal Soci- ety. Thus were the foundations of thermodynamics laid. This bril- hant development and generalization of the subject (which had grown with startling rapidity from the moment when Helmholtz de- nied perpetual motion and Thomson grasped the conception of the absolute zero) did not content Thomson. He must follow its appli- cations to human needs and the cosmic consequences it involved. And so he not only suggested the process of refrigeration by the sudden expansion of compressed cooled air, but propounded the doctrine of the dissipation of energy. If the availability of the energy in a hot body be proportional to its absolute temperature, it follows that as the earth and the sun—nay, the whole solar system itself—cool down toward one uniform level of temperature, all life must perish and all energy become unavailable. This far-reaching conclusion ¢ once more suggested the question of a beginning, a question which, as already remarked, had arisen in the consideration of the Fourier doctrine of the flow of heat. In 1852, at the age of 28, William Thomson married Margaret Crum and resigned his Cambridge fellowship. “The happiness of his life was, however, shadowed by his wife’s precarious health, necessi- tating residence abroad at various times. In the summer of 1855 they stayed at Kreutznach, from which place Thomson wrote to Helmholtz, inviting him to come to England in September to attend the British Association meeting at Glasgow. He assured Helmholtz that his presence would be one of the most interesting events of the gathering, so that he hoped to see him on this ground, but also looked forward with the greatest pleasure to the opportunity of making his acquaintance, as he had desired this ever since the Conservation of Energy had come into his hands. Accordingly, on July 29 Helmholtz left Konigsberg for Kreutznach, to make the acquaintance of Thom- a“ There is at present in the material world a universal tendency to the dissi- pation of mechanical energy. Within a finite period of time past the earth must have been and within a finite period of time to come the earth must again be unfit for the habitation of man as at present constituted, unless operations have been or are to be performed which are impossible under the laws to which the known operations going on at present in the material world are subject.” (Mathematical and Physical Papers, Vol. I, p. 514.) 754 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. son before his journey to England. On August 6 he wrote to Frau Helmholtz that Thomson had made a deep impression on him. I expected to find the man, who is one of the first mathematical physicists of Europe, somewhat older than myself and was not a little astonished when a very juvenile and exceedingly fair youth who looked quite girlish came for- ward. He had taken a room for me close by and made me fetch my things from the hotel and put up there. He is at Kreutznach for his wife’s health. She appeared for a short time in the evening, and is a charming and inftel- lectual lady, but is in very bad health. He far exceeds all the great men of science with whom I have made personal acquaintance, in intelligence, and lucidity, and mobility of thought, so that I felt quite wooden beside him some- times. A year later Helmholtz again met the Thomsons at Schwalbach. Writing to his father, he described Thomson as “ certainly one of the first mathematical physicists of the day, with powers of rapid inven- tion such as I have seen in no other man.” In 1860, after the death of Mrs. Helmholtz, the great German philosopher again visited Brit- ain, staying with the Thomsons for some weeks in the island of Arran. In 1863 Helmholtz, who in the meantime had married again, came to England and visited the chief universities, and in writing to his wife gives an amusing picture of his doings. My journey to Glasgow went off very well. The Thomsons have lately moved to live in the university buildings (the old college) ; formerly they spent more time in the country. He takes no holiday at Easter, but his brother James, pro- fessor of engineering at Belfast, and a nephew who is a student there, were with him. The former is a level-headed fellow, full of good ideas, but cares for nothing except engineering, and talks about it ceaselessly all day and all night, so that nothing else can be got in when he is present. It is really comic to see how the two brothers talk at one another and neither listens, and each holds forth about quite different matters. But the engineer is the most stubborn, and generally gets through with his subject. In the intervals I have seen a quantity of new and most ingenious apparatus and experiments of W. Thomson, which made the two days very interesting. He thinks so rapidly, however, that one has to get at the necessary information about the make of the instruments, etc., by a long string of questions, which he shies at. How his students understand him without keeping him as strictly to the subject as I ventured to do is a puzzle to me; still there were numbers of students in the laboratory hard at work, and apparently quite understanding what they were about. 'Thomson’s experiments, however, did for my new hat. He had thrown a heavy metal disk into very rapid rotation, and it was revolving on a point. In order to show me how rigid it became on rotation he hit it with an iron hammer, but the disk resented this, and it flew off in one direction and the iron foot on which it was revolving in another, carrying my hat away with it and ripping it up. But we are anticipating. Hitherto Thomson’s work had been mainly in pure science; but toward the end of the fifties, while still in the midst of thermodynamic studies, events were progressing which drew him with irresistible force toward the practical applications that made him famous. Indeed, it could hardly be otherwise, seeing LIFE AND WORK OF LORD KELVIN—THOMPSON. 755 that he was master in whatever he touched. Early in 1853 he had communicated to the Glasgow Philosophical Society a paper “ On transient electric currents,” ¢ in which he investigated mathematically the discharge of a Leyden jar through circuits possessing self-induc- tion as well as resistance. Faraday and Reiss had observed that in certain cases the gases produced by the discharge of sparks through water consisted of mixed oxygen and hydrogen, and Helmholtz had conjectured that in such cases the spark was oscillatory. Thomson determined to test mathematically what was the motion of electricity at any instant after making contact in a circuit under given condi- tions. He founded his solution on the equation of energy, ingeniously building up the differential equation and then finding the integral. The result was very remarkable. He discovered that a critical rela- tion occurred if the capacity in the circuit was equal to four times the coefficient of self-induction divided by the square of the resistance. If the capacity was less than this the discharge was oscillatory, passing through a series of alternate maxima and minima before dying out. If the capacity was greater than this the discharge was nonoscillatory, the charge dying out without reversing. This beautiful bit of math- ematical analysis, which passed almost unnoticed at the time, laid the foundation of the theory of electric oscillations subsequently studied by Oberbeck, Schiller, Hertz, and Lodge, and forms the basis of wire- less telegraphy. Fedderssen in 1859 succeeded in photographing these oscillatory sparks, and sent photographs to Thomson, who with great delight gave an account of them to the Glasgow Philosophical Society. At the Edinburgh meeting of the British Association in 1854 Thomson read a paper “ On mechanical antecedents of motion, heat, and light.” Starting with some now familiar, but then novel, gen- eralities about energy, potential and kinetic, and about the idea of stores of energy, the author touched on the source of the sun’s heat and the energy of the solar system, and then reverted to his favorite argument from Fourier, according to which, if traced backward, there must have been a beginning to which there was no antecedent. This was a nonmathematical exposition of work which, as his notebooks show, had been going on from 1850 in a very stiff mathematical form in which Fourier’s equations for the flow of heat in solids were ap- plied to a number of outlying problems involving kindred mathe- matics, including the diffusion of fluids and the diffusion or trans- mission of electric signals through long cables. The Proceedings of the Royal Society for 1854 contain the investigation of cables under the title “On the theory of the electric telegraph.” Faraday had @Proe. Glasgow Philos. Soe., January, 1853; Phil. Mag., June, 1853; and Mathematical and Physical Papers, Vol. I, p. 534. 756 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. predicted that there would be retardation of signals in cables owing to the coating of gutta-percha acting like the glass of a Leyden jar. Forming the required differential equation and applying Fourier’s integration of it, Thomson drew the conclusion that the time required for the current at the distant end to reach a stated fraction of its steady value would be proportional both to the resistance and to the capacity; and as both of these are proportional to the length of the cable, the retardation would be proportional to the square of the length. This is the famous law of squares about which so much dispute arose. This was followed by a further research “ On peri- staltic induction of electric currents,” communicated to the British Association in 1855, and afterwards in more complete mathematical form to the Royal Society. Submarine telegraphy was “in the air.” John and Jacob Brett had pioneered the project for a Dover-Calais cable, and in 1851 Crampton successfully united England and France. In 1853 Holy- head and Howth were connected by Mr. (later Sir) Charles Bright. And these were followed by the Dover-Ostend and longer cables. Atlantic telegraphy became the dream of the telegraph engineer. Cyrus W. Field, in 1856, negotiated a cable across the Gulf of St. Lawrence, thus connecting Newfoundland to the American continent. The Atlantic Telegraph Company was formed, with capital mostly subscribed in England, to promote the great enterprise to join Ire- land to Newfoundland. Field, Brett, Bright, Statham, and Wild- man Whitehouse were the chief promoters. Bright was engineer, Whitehouse (a retired medical man) electrician. In a pamphlet issued by the company, in July, 1857, narrating the preliminary pro- ceedings, the names of John Pender, of Manchester, and Professor Thomson, of “2, The College, Glasgow,” are included in the lst of directors; and the statement is made that “the scientific world is particularly indebted to Prof. W. Thomson, of Glasgow, for the attention he had given to the theoretical investigation of the condi- tions under which electrical currents move in long insulated wires, and Mr. Whitehouse has had the advantage of this gentleman’s presence at his experiments, and counsel, upon several occasions, as well as the gratification resulting from his countenance and coopera- tion as one of the directors of the company.” This is one side of the matter. The other side is that Mr. Whitehouse had, at the British Association meeting in 1856, read a paper challenging the law of squares, and declaring that if it was true Atlantic telegraphy was hopeless. He professed to refute it by experiments, the true sig- nificance of which was disposed of by Thomson in two letters in The Atheneum. He pointed out that success lay primarily in adequate section of conductor, and hinted at a remedy (deduced from LIFE AND WORK OF LORD KELVIN—THOMPSON. hod Fourier’s equations), which he later embodied in the curb signal transmitter, namely, that the coefficient of the simple harmonic term in the expression for the electrical potential shall vanish. In Decem- ber, 1856, he described to the Royal Society his plan for receiving messages, namely, a sort of Helmholtz tangent galvanometer, with copper damper to the suspended needle, the deflections being observed by watching through a reading telescope the image of a scale re- flected from the polished side of the magnet or from a small mirror carried by it. As we all know, he abandoned this subjective method for the objective plan in which a spot of hght from a lamp is reflected by the mirror upon a scale. There is a pretty story—which is believed to be true—that the idea of thus using the mirror arose from noticing the reflection of light from the monocle which, being short-sighted, he wore hung around his neck with a ribbon. The story of the Atlantic cable, of the failure of 1857, of the brief success of 1858, has so often been told that it need not be emphasized here. Thomson, after the failure of the first attempt, was called upon to take a more active part. He had discovered to his surprise that the conductivity of copper was greatly affected—to an extent of 30 or 40 per cent—by its purity. So he organized a system of testing conductivity at the factory where the additional lengths were being made, and was put in charge of the test room on board the Agamemnon in 1858. Whitehouse was unable to join the expedition, and Thomson, at the request of the directors, undertook the post of electrician in charge, without any recompense, though the tax on his time and energies was very great. Sir Charles Bright has given us the following little silhouette of Thomson : As for the professor * * *, he was a thorough good comrade, good all round, and would have taken his “turn at the wheel” (of the paying-out brake) if others had broken down. He was also a good partner at whist when work wasn’t on; though sometimes, when momentarily immersed in cogibun- dity of cogitation, by scientific abstraction, he would look up from his cards and ask, ‘“ Wha played what?’ After various disheartening mishaps success crowned their efforts. Throughout the voyage Thomson’s mirror galvanometer had been used for the continuity tests and for signaling to shore, with a bat- tery of 75 Daniell cells. The continuity was reported perfect, and the insulation had improved on submersion. On August 5 the cable was handed over to Mr. Whitehouse and reported to be in perfect condition. Whitehouse at once abandoned the Thomson mirror in- struments and began working with his own patented apparatus using heavy relays and a special transmitter with induction coils. He sent in no report to the directors for a week, while he made ineffectual 758 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. attempts with bigger induction coils to get his apparatus to work. After more than a week the reflecting galvanometer and ordinary Daniell cells were resumed, and then clear messages were inter- changed and international congratulations. News of peace with China and of the end of the Indian mutiny was transmitted; but the insulation was found to be giving way, and on October 20, after 732 messages had been conveyed, the cable spoke no more. It had been destroyed by Whitehouse’s bungling use of induction coils, some 5 feet long, working at some 2,000 volts! Of the part played by Thomson in the next eight years, in prepara- tion for the cables of 1865 and 1866, there is not time to speak. Suffice it to say that throughout the preparations, the preliminary trials, the interrupted voyage of 1865, when 1,000 miles were lost, the successful voyage of 1866, when the new cable was laid and the lost one recovered from the ocean and completed, Thomson was the ruling spirit whose advice was eagerly sought and followed. On his return he was knighted for the part he played so well. He had in the mean- time made further improvements in conjunction with Cromwell Varley. In 1867 he patented the siphon recorder, and, in conjunc- tion with Fleeming Jenkin, the curb transmitter. He was consulted on practically every submarine-cable project from that time forth. Thomson’s activities during the sixties were immense. Beside all this telegraphic work he was incessant in research. He had under- taken serious investigations on the conductivity of copper. He was urging the application of improved systems of electric meas- urement and the adoption of rational units. When in 1861 Sir Charles Bright and Mr. Latimer Clark proposed names for the prac- tical units based on the centimeter-gram-second absolute system, Sir William Thomson gave a cordial support; and on his initiative was formed the famous committee of electrical standards of the British Association, which year by year has done so much to carry to perfec- tion the standards and the methods of electrical measurement. He was largely responsible for the international adoption of the system of units by his advocacy of them at the Paris congress in 1881 and in subsequent congresses. He was an uncompromising advocate of the metric system, and lost no opportunity of denouncing the “absurd, ridiculous, time-wasting, brain-destroying British system of weights and measures.” His lecture in 1883 at the Civil Engineers may be taken as a summary of his views, and it gives a glimpse of his mental agility. So early as 1851 he had begun to use the absolute system, stimulated thereto by the earlier work of Gauss and Weber. The fact that terrestrial gravity varies at different regions of the earth’s surface by as much as half of 1 per cent compelled the use of absolute methods where any greater accuracy than this is required. “ For LIFE AND WORK OF LORD KELVIN—THOMPSON. 759 myself,” he said, ‘what seems the shortest and surest way to reach the philosophy of measurement—an understanding of what we mean by measurement, and which is essential to the intelligent practice of the mere art of measuring—is to cut off all connection with the earth.” And so he imagined a traveler with no watch or tuning fork or meas- uring rod wandering through the universe trying to recover his centi- meter of length and his second of time and reconstructing thereupon his units and standards from the wave length of the yellow light of sodium and the value of wv the velocity of light from experiments on the oscillations in the discharge of a Leyden jar! Some of us in this very room remember how we listened amazed to this characteristic and bewildering excursus. Among the activities of these fruitful years was a long research on the electrodynamic qualities of metals—thermoelectric, thermoelastic, and thermomagnetic. These formed the subject of his Bakerian lec- ture of 1856, which occupies no fewer than 118 pages of the reprinted Mathematical and Physical Papers. He worked hard also at the mathematical theory of magnetism. Faraday’s work on diamagnet- ism had appeared while Thomson was a student at Cambridge. It established the fact that magnetic forces were not mere actions at a distance between supposed poles, but actions dependent on the sur- rounding medium; and Thomson set himself to investigate the matter mathematically. Faraday and Fourier had been the heroes of Thom- son’s youthful enthusiasm; and, while the older mathematicians shook their heads at Faraday’s heretical notion of curved lines of force, Thomson had, in 1849 and 1850, developed a new theory with all the elegance of a mathematical disciple of Poisson and Laplace, discuss- ing solenoidal and lamellar distributions by aid of the hydrodynamic equation of continuity. To Thomson we owe the terms “ permeabil- ity ” and “ susceptibility,” so familiar in the consideration of the mag- netic properties of iron and steel. He continued to add to and revise this work through the sixties and seventies. In 1859-60 Thomson was studying atmospheric electricity, writing on it in Nichol’s Cyclopedia and lecturing on it at the Royal Institu- tion. For this study he invented the water-dropping collector, and vastly improved the electrometer, which developed into the elaborate forms of the quadrant instrument and other types described in the B. A. report of 1867. During this work he discovered the fact that the sudden charge or discharge of a condenser is accompanied by a sound. He also measured electrostatically the electromotive force of a Daniell cell, and investigated the potentials required to give sparks of different lengths in the air. In the winter of 1860-61 Thomson met with a severe accident. He fell on the ice when engaged at Largs in the pastime of curling and 88292—sm 1908-49 760 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. broke the neck of his thigh. For several months he had to le on his back; and it was at this time that he adopted the famous green note- books, which ever afterwards were the companions of his days. The accident left him with a slight limp for the rest of his life. An admirable picture of Lord Kelvin as he was in the sixties, moving among his students and incessant in his researches, has been given in The Times of January 8, 1908, by Professor Ayrton, who was then working at Glasgow. In these years Thomson was also writing on the secular cooling of the earth and investigating the changes of form during rotation of elastic spherical shells. And as if this were not enough to have had in hand, he embarked with his friend, Professor Tait, on the preparation of a text-book of natural philosophy. There was at that date no satisfactory work to put into the hands of stu- dents, and he must supply the need. At first a short pamphlet of propositions on statics and dynamics, culled by Prof. John Ferguson from mere lecture notes, was printed for the use of students. Thom- son had told Helmholtz of his purpose, and in 1862 Helmholtz wrote him: Your undertaking to write a text-book of natural philosophy is very praise- _ worthy, but will be exceedingly tedious. At the same time I hope it will sug- gest ideas to you for much valuable work. It is in writing a book like that that one best appreciates the gaps still left in science. The first volume of Thomson and Tait’s Treatise on Natural Phi- losophy was published in 1867, the second only in 1874; when it ap- peared that Helmholtz’s hopes were just. For in approaching the subject of elasticity the gaps still left were found to be such that whole new mathematical researches were necessary before Volume I could be finished. Thomson’s contributions to the theory of elastic- ity are no less important than those he made to other branches of physics. In 1867 he communicated to the Royal Society of Edin- burgh his famous paper “ On vortex atoms.” Helmholtz had pub- lished a mathematical paper on the hydrodynamic equations of vor- tex motion, proving that closed vortices could not be produced in a liquid perfectly devoid of internal friction. Thomson seized on this idea. If no such vortex could be artificially produced, then if such existed it could not be destroyed. But being in motion and having the inertia of rotation, it would have elastic and other properties. He showed that vortex rings (like smoke rings in air) in a perfect me- dium are stable, and that in many respects they possess the qualities essential to the properties of material atoms—permanence, elasticity, and power to act on one another through the medium at a distance. The different kinds of atoms known to the chemist as elements were to be regarded as vortices of different degrees of complexity. Though he seemed at the end of his life to doubt whether the vortex-atom LIFE AND WORK OF LORD KELVIN—THOMPSON. 761 hypothesis was adequate to explain all the properties of matter, the conception remains to all time a witness to his extraordinary powers of mind. In 1870 Lady Thomson, whose health had been failing for several years, died. In the same year the University of Glasgow was re- moved from the site it had occupied for over four centuries to the new and splendid buildings on Gilmore Hill, overlooking the Kelvin River. Sir William Thomson had a house here in the terrace as- signed for the residences of the professors, adjoining his laboratory and lecture room. From his youth he had been fond of the sea, and had early owned boats of his own on the Clyde. For many years his sailing yacht, the Lalla Rookh, was conspicuous, and he was an ac- complished navigator. His experiences in cable laying had taught him much, and in return he was now to teach science in navigation. First he reformed the mariner’s compass, lightening the moving parts to avoid protracted oscillations and to facilitate the correction of the quadrantal and other errors arising from the magnetism of the ship’s hull. At first the Admiralty would have none of it. But the com- pass is now all but universally adopted both in the navy and in the mercantile marine. Dissatisfied with the clumsy appliances used in sounding, when the ship had to be stopped before the sounding line could be let down, he devised the now well-known apparatus for taking flying sound- ings by using a line of steel piano wire. He had great faith in navi- gating by use of sounding line, and once told me—apropos of a recent wreck near the Lizard, which he declared would have been impossible had soundings been regularly taken—how in a time of a continuous fog he brought his yacht all the way across the Bay of Biscay into the Solent, trusting to soundings only. He also published a set of tables for facilitating the use of Sumner’s method at sea. He was vastly interested in the question of the tides, not merely as a sailor, but because of the interest attending their mathematical treatment in connection with the problems of the rotation of spheroids, the harmonic analysis of their complicated periods by Fourier’s methods, and their relation to hydrodynamic problems generally. He invented the tide-predicting machine, which will predict for any given port the rise and fall of the tides, which it gives in the form of a con- tinuous curve recorded on paper, the entire curves for a whole year being inscribed by the machine automatically in about four hours. Further than this, adopting a beautiful mechanical integrator, the device of his ingenious brother, Prof. James Thomson, he invented a harmonic analyzer—the first of its kind—capable not only of solving differential equations of any order, but of analyzing any given periodic curve and exhibiting the values of the coefficients of the 762 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. -various terms of the Fourier series. Wave problems always had a fascination for him, and the work of the mathematicians Poisson and Cauchy on the propagation of wave motion were familiar studies. In his lectures he used to say, “ The great struggle of 1815 ”—and then paused, while his students, thinking of Waterloo, began to applaud— was not that fought out on the plains of Belgium, but who was to rule the waves, Cauchy or Poisson.” In 1871 Helmholtz went with Sir William Thomson on the yacht Lalla Rookh to the races at Inverary, and on some longer excursions to the Hebrides. Together they studied the theory of waves, “ which he loved,” says Helmholtz, “ to treat as a race between us.” Returning, they visited many friends. “It was all very friendly,” wrote Helmholtz, “ and unconstrained. Thomson presumed so much on his intimacy with them that he always carried his mathematical notebook about with him, and would begin to calculate in the midst of the company if anything occurred to him, which was treated with a certain awe by the party.” He possessed, indeed, the faculty of detachment, and would settle quietly down with his green book, almost unconscious of things going on around him. On calm days he and Helmholtz ex- perimented on the rate at which the smallest ripples on the surface of the water were propagated. Almost the last publications of Lord Kelvin were a series of papers on “ Deep-Sea Ship Waves,” com- municated between 1904 and 1907 to the Royal Society of Edinburgh. In 1874, on June 17, Sir William Thomson married Miss Frances Anna Blandy, of Madeira, whom he had met on cable-laying expedi- tions. Lady Kelvin, who survives him, became the center of his home in Glasgow and the inseparable companion of all his later trav- els. He built at Netherhall, near Largs, a beautiful mansion in the Scottish baronial style; and though he latterly had a London house in Eaton Place, Netherhall was the home to which he retired when he withdrew from active work in the University of Glasgow. Throughout the seventies and eighties Sir William Thomson’s scientific activities were continued with untiring zeal. In 1874 he was elected president of the Society of Telegraph Engineers, of which, in 1871, he had been a foundation member and vice-president. In 1876 he visited America, bringing back with him a pair of Graham Bell’s earliest experimental telephones. He was president of the Mathematical and Physical Section of the British Association of that year at Glasgow. Among the matters that can not be omitted in any notice of his life was Lord Kelvin’s controversy with the geologists. He had from three independent lines of argument inferred that the age of the earth could not be infinite, and that the time demanded by the geolo- gists and biologists for the development of life must be finite. He LIFE AND WORK OF LORD KELVIN—THOMPSON. 763 himself estimated it at about a hundred million of years at the most. In vain did the naturalists, headed by Huxley, protest. He stuck to his propositions with unrelaxing tenacity but unwavering courtesy. “ Gentler knight never broke lance ” was Huxley’s dictum of his op- ponent. His position was never really shaken, though the later researches of Perry, and the discovery by Strutt of the degree to which the constituent rocks of the earth contain radioactive matter, the disgregation of which generates internal heat, may so far modify the estimate as to increase somewhat the figure which he assigned. The completion of the second edition of Vol. I of the Thomson and Tait Treatise—no more was ever published—and the collection of his own scattered researches, was a work extending over some years. In addition he wrote for the Encyclopedia Britannica, of 1879, the long and important articles on “ Elasticity ” and “ Heat.” In 1871 he was president of the British Association at its meeting in Edinburgh. In his Presidential Address, which ranged lumi- nously over the many branches of science within the scope of the association, he propounded the suggestion that the germs of life might have been brought to the earth by some meteorite. With the advent of electric lighting at the end of the seventies Thomson’s attention was naturally attracted to this branch of the practical applications of science. He never had any prejudice against the utilization of science for practical ends. He wrote: There can not be a greater mistake than that of looking superciliously upon practical applications of science. The life and soul of science is its practical application; and just as the great advances in mathematics have been made through the desire of discovering the solution of problems which were of a highly practical kind in mathematical science, so in physical science many of the greatest advances that have been made from the beginning of the world to the present time have been made in the earnest desire to turn the knowledge of the properties of matter to some purpose useful to mankind. And so he scorned not to devise instruments and appliances for commercial use. His electrometers, his galvanometers, his siphon recorders, and his compasses had been made by James White, optician, of Glasgow. In this firm he became a partner, taking the keenest commercial interest in its operations, and frequenting the factory to superintend the construction of apparatus. New measuring instru- ments were required. He set himself to devise them, designing poten- tial galvanometers, ampere gauges, and a whole series of standard electric balances for electrical engineers. Lord Kelvin’s patented inventions were very numerous. Without counting in those since 1900, taken mostly in the name of Kelvin and James White, they number 56. Of these 11 relate to telegraphy, 11 relate to compasses and navigation apparatus, 6 relate to dynamo machines or electric lamps, 25 to electric measuring instruments, 1 ° 764 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. to the electrolytic production of alkali, and 2 to valves for fluids. He was an independent inventor of the zigzag method of winding alternators, which the public knew under the name of Ferranti’s machine, which was manufactured under royalties payable to him. He was interested even in devising such details as fuses and the sus- pension pulleys with differential gearing by which incandescent lamps can be raised or lowered. He gave evidence before a parliamentary committee on electric lighting and discussed the theory of the electric transmission of power, pointing out the advantage of high voltages. The introduc- tion into England in 1881 of the Faure accumulator excited him greatly. In his Presidential Address to the Mathematical and Physi- cal Section of the British Association at York that year he spoke of this and of the possibility of utilizing the powers of Niagara. He also read two papers, in one of which he showed mathematically that in a shunt dynamo best economy of working was attained when the resistance of the outer circuit was a geometric mean between the re- sistances of the armature and of the shunt. In the other he laid down the famous law of economy of copper lines for the transmission of power. Helmholtz, visiting him again in 1884, found him absorbed in regulators and measuring apparatus for electric lighting and electric railways. “On the whole,” Helmholtz wrote, “ I have an impression that Sir William might do better than apply his eminent sagacity to industrial undertakings; his instruments appear to me too subtle to be put into the hands of uninstructed workmen and officials. * * * He is simultaneously revolving deep theoretical projects in his mind, but has no leisure to work them out quietly. As far as that goes, I am not much better off.” But he shortly added, “ I did Thomson an injustice in supposing him to be wholly immersed in technical work; he was full of speculations as to the original properties of bodies, some of which were very difficult to follow; and, as you know, he will not stop for meals or any other consideration.” And, indeed, Thom- son had weighty things in his mind. He was revolving over the speculations which later in the same year he was to pour out in such marvelous abundance in his famous 20 lectures in Baltimore “ On molecular dynamics and the wave theory of light.” These lectures, delivered to 26 hearers, mostly accomplished teachers and professors, were reported verbatim at the time and reprinted by him with many revisions and additions in 1904. Of this extraordinary work, done at the age of 60, it is difficult to speak. Day after day he led the 26 “ coefficients ” who sat at his feet through the mazes of solid-elastic theory and the spring-shell molecule, newly invented in order to give a conception how the molecules of matter are related to the ether through which light waves are propagated. All his life he had been endeavoring to discover a rational mechanical explanation for the LIFE AND WORK OF LORD KELVIN—THOMPSON. 765 most recondite phenomena—the mysteries of magnetism, the marvels of electricity, the difficulties of crystallography, the contradictory properties of ether, the anomalies of optics. While Thomson had been seeking to explain electricity and magnetism and light dynamic- ally, or as mechanical properties, if not of matter, at least of mole- cules, Maxwell (the most eminent of his many disciples) had boldly propounded the electromagnetic theory of light and had drawn all the younger men after him in acceptance of the generalization that the waves of light were essentially electromagnetic displacements in the ether. ‘Thomson had never accepted Maxwell’s theory. It is true that in 1888 he gave a nominal adhesion, and in the preface which, in 1893, he wrote to Hertz’s Electric Waves, he himself uses the phrase “ the electromagnetic theory of light, or the undulatory theory of magnetic disturbance.” But later he withdrew his adhesion, pre- ferring to think of things in his own way. Thomson’s Baltimore lec- tures, abounding, as they do, in brilliant and ingenious points, and ranging from the most recondite problems of optics to speculations on crystal rigidity, the tactics of molecules and the size of atoms, leave one with the sense of being a sort of protest of a man persuaded against his own instincts and struggling to find new expression of his thoughts so as to retain his old ways of regarding the ultimate dynamics of physical nature. ; One characteristic of all Lord Kelvin’s teaching was his peculiar fondness for illustrating recondite notions by models. Possibly he derived this habit from Faraday; but he pushed its use far beyond anything prior. He built up chains of spinning gyrostats to show how the rigidity derived from the inertia of rotation might illustrate the property of elasticity. The vortex-atom presented a dynamical picture of an ideal material system. He strung together little balls and beads with sticks and elastic bands to demonstrate crystalline dynamics. On the use of the model to illustrate physical principles he spoke as follows at Baltimore: My object is to show how to make a mechanical model which shall fulfill the conditions required in the physical phenomena that we are considering, what- ever they may be. At the time when we are considering the phenomena of elasticity in solids I shall want a model of that. At another time, when we have vibrations of light to consider, I shall want to show a model of the action exhibited in that phenomenon. We want to understand the whole about it: we only understand a part. It seems to me that the test of ‘Do we or do we not understand a particular subject in physics?” is “ Can we make a mechanical model of it?” I have an immense admiration for Maxwell’s mechanical model of electromagnetic induction. And again Lord Kelvin says: I never satisfy myself until I can make a mechanical model of a thing. If I can make a mechanical model, I can understand it. As long as I can not make a mechanical model all the way through I can not understand it. 766 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. This use of models has become characteristic of the tone and temper of British physicists. Where Poisson or Laplace saw a mathematical formula, Kelvin, with true physical imagination, discerned a reality which could be roughly simulated in the concrete. And throughout all his mathematics his grip of the physical reality never left him. According to the standard that Kelvin set before him, it is not suffi- cient to apply pure analysis to obtain a solution that can be com- puted. Every equation, “every line of the mathematical process must have a physical meaning, every step in the process must be asso- ciated with some intuition; the whole argument must be capable of being conducted in concrete physical terms.” * In other words, Lord Kelvin, being a highly accomplished mathematician, used his mathe- matical equipment with supreme ability as a tool; he remained its master and did not become its slave. Once Lord Kelvin astonished the audience at the Royal Institu- tion by a discourse on “ Isoperimetrical problems,” endeavoring to give a popular account of the mathematical process of determining a maximum or minimum, which he illustrated by Dido’s task of cutting an oxhide into strips so as to inclose the largest piece of ground; by Horatius Cocles’s prize of the largest plot that a team of oxen could plow in a day; and by the problem of running the shortest railway line between two given points over an uneven coun- try. On another occasion he entertained the Royal Society with a discourse on the “ Homogeneous partitioning of space,” in which the fundamental packing of atoms was geometrically treated, affording incidentally the theory of the designing of wall-paper patterns. To the last Lord Kelvin took an intense interest in the most re- cent discoveries. Electrons—or “ electrions,” as he called them— were continually under discussion. He prided himself that he had read Rutherford’s book on Radio-activity again and again. He ob- jected, however, in toto to the notion that the atom was capable of division and disintegration. In 1903, in a paper called “Aepinus atomized,” he reconsidered the views of Aepinus and Father Bosco- vich from the newest standpoint, modifying Aepinus’s theory to suit the notion of electrons. After taking part in the British Association meeting of 1907 at Leicester, where he entered with surprising activity into the dis- cussions of radio-activity and kindred questions, he went to Aix les Bains for change. He had barely reached home at Largs in Sep- tember when Lady Kelvin was struck down with a paralytic seizure. Lord Kelvin’s misery at her hopeless condition was intense. He had himself suffered for fifteen years from recurrent attacks of facial neuralgia, and in 1906 underwent a severe operation. Under these ¢Pprof. A. EK. H. Love. LIFE AND WORK OF LORD KELVIN—-THOMPSON. 167 afflictions he had visibly aged, and the illness of Lady Kelvin found him little able physically to sustain the anguish of the stroke. He wandered distractedly about the corridors of his house, unable at last to concentrate his mind on the work at hand. A chill seized him, and after about a fortnight of prostration he sank slowly and quietly away. He was buried in Westminster Abbey, with national honors, on December 23, 1907. The sympathies of all of us go out to the gracious lady who sur- vives him and who with such assiduous devotion tended him in his declining ycars. Honors fell thickly on Lord Kelvin in his later life. He was President of the Royal Society from 1890 to 1894. He had been made a Fellow of the Royal Society in 1851 and in 1883 had been awarded the Copley medal. He was raised to the peerage in 1892. He was one of the original members of the Order of Merit, founded in 1902; was a grand officer of the Legion of Honor; and held the Prussian order Pour le Mérite; in 1902 was named a privy councilor. In 1904 he was elected chancellor of the university, in which he had filled the chair of natural philosophy for fifty-three years. He had celebrated his jubilee with unusual marks of world-wide esteem in 1896, and finally retired in 1899. He was a member of every foreign academy, and held honorary degrees from almost every university. In 1899 we elected him an honorary member of our institution. In politics he was, up to 1885, a broad Liberal; but, as was natural in an Ulsterman, became an ardent Unionist on the introduction of the home-rule bill. He once told me that he preferred Chamber- lain’s plan of home rule with four Irish parliaments—one in each province. In religion Lord Kelvin was an Anglican—at least from his Cam- bridge days, but when at Largs attended the Presbyterian Free Chureh. His simple, unobtrusive, but essential piety of soul was unclouded. He had a deep detestation of ritualism and sacerdotal- ism, which he hated heart and soul in all its forms; and he denounced spiritualism as a loathsome and vile superstition. His profound studies had led him again and again to contemplate a beginning to the order of things, and he more than once publicly professed a pro- found and entirely unaffected belief in Creative Design. Kindly hearted, lovable, modest to a degree almost unbelievable, he carried through life the most intense love of truth and an insa- tiable desire for the advancement of naturat knowledge. Accurate and minute measurement was for him as honorable a mode of advanc- ing knowledge as the most brilliant or recondite speculation. At both ends of the scale his preeminence in the quest for truth was un- 768 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. challenged. _If he could himself at the end of his long career describe his own efforts as “ failure,” it was because of the immensely high ideal which he set before him. “I know,” he said on the day of his jubilee, “no more of electric and magnetic force, or of the rela- tion between ether, electricity, and ponderable matter, or of chemical affinity, than I knew and tried to teach to my students in my first session.” Yet which of us has not learned much of these things because of his work? We of this Institution of Electrical Engineers may well be proud of him—proud that he was one of our first mem- bers, that he was thrice our president, and that as our president he died. We shall not look upon his like again. “He conceived the possibility of formulating a comprehensive molecular theory, definite and complete, “in which all physical science will be represented with every property of matter shown in dynamical relation to the whole.” Presidential Address to the British Association, 1871, reprinted in Popular Lectures and Addresses, Vol. II, p. 1638. PLATE 1. Broca. Smithsonian Report, 1908. HENRI BECQUEREL. THE WORK OF HENRI BECQUEREL* (With 1 plate.) By ANDRE Broca. INTRODUCTION. It is no small nor easy task to retrace the life of Henri Becquerel, unveiling his inner hfe and showing how in a life consecrated to daily labor, moment by moment, he accumulated the great mass of scientific material which, in his thirtieth year, opened to him the doors of the Académie des Sciences, and how finally, through the logical development of his train of thought, he reached the discovery which has immortalized his name. It was an instructive spectacle to see Becquerel in his laboratory arranging his apparatus with consummate skill, often constructing it from odd pieces of card or of copper wire, which seemed alive under his fingers, and with which he made the discoveries which form his memoirs. Foreign scientists who came in throngs to see each new experiment could scarcely believe a laboratory so barren could yield so abundant a harvest. They were astonished and charmed at their reception, so simple and cordial, where they awaited the formal dig- nity of a man so eminent. The laboratory seemed his normal place. Experimental research, in the accomplishment of which he braved every difficulty, seemed to be in him a vertiable physiological func- tion. Becquerel made physics from all that fell under his hands. He was raised for physics and by a physicist. The most precious memo- ries, and with which he often entertained his friends, were of his father and grandfather, whose discourse and example had helped to shape his mind. In his youth the great reward for his vacation days was to enter the laboratory of his father and see the old or new experiments, to perform those within his ability, fashioning the ap- paratus with his own hands. One of his most vivid recollections was seeing his father come in one noon from his laboratory to announce @Translated, by permission, from Revue générale des Sciences pures et appliquées. Paris, 19th year, No. 20, October 30, 1908. 769 770 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. to his grandfather the invention of the phosphoroscope, discussing it and its results, which the following day more than verified. Becquerel recounted these circumstances with no boastful spirit, but rather to attribute to his up-bringing much of his success. He had the joy of seeing his son enter with distinction the same career and to be able to transmit what had been his own heritage. AI- though trained in science, his artistic tastes were not undeveloped. In painting he was an enlightened connoisseur, owing this trait to his ancester, Girodet, of whom he possessed some masterpieces, among others admirable drawings, which he liked to show to his friends and whose beauty he appreciated. His morals were of the highest, and he had a horror of all duplicity and deceit. He had for all questions the broadest and most enlight- ened tolerance. That spirit whose every effort strove for the attain- ment of scientific truth knew how to avoid the lure of insufficient evidence. While holding a clear-cut personal opinion, he was always tolerant of any opinion of others having for its purpose the eleva- tion of morals. This explains how he entered the Ecole Polytechnique at 19, in 1873; how from there he entered the Ponts-et-chausées and published his first work at 22 years of age, in the year following his graduation from the Ecole Polytechnique. From then until his death he never ceased to publish works more and more remarkable. The Ecole Polytechnique made him a lecturer in physics while he was yet only an engineering student in order to give him the place as professor upon the retirement of Potier, and the museum judged him worthy of holding the chair already made illustrious by his father and grandfather and held before them by Guy-Lussac. Merited honors have never ceased to be his recompense; he was a member of the more renowned foreign scientific bodies, the Royal Society of Lon- don, the Academy of Berlin, the Académie Royale dei Lincei, the National Academy of Washington. He received the medals and prizes held in the highest esteem—the Rumford prize of London, in 1900; the Helmholtz medal of Berlin, in 1901; the Nobel prize, in 1903; the Barnard medal of the United States, in 1903. The Aca- démie des Sciences made him its president in 1908, and at the same time the Société Francaise de Physique bestowed upon him the widely coveted title of “honorary member,” and at the death of Lapparent he was almost unanimously named its permanent secretary. He was but 55 and seemed destined to long hold this worthy honor when death cruelly snatched him away but a few weeks after he received it. Before a blow so cruel it is useless to express our regrets. The homage due such a man and worthy of the memory which his own family, his friends, scientists, and the whole world will retain is to retrace as fully as is possible the history of his scientific achievements. WORK OF HENRI BECQUEREL—BROGA. egal HENRI BECQUEREL BEFORE RADIO-ACTIVITY. The problems which preoccupied Becquerel during his entire life related to the constitution of matter and the manner in which this reacts upon the magnetic and optical properties of bodies. He approached the problem through rotary magnetic polarization and his theories led him to laws of primordial importance. He was the first to admit that in molecular phenomena there must be a par- tial carrying along of the ether by matter, and from this hypothesis he deduced the formula— R ——__—_—= constant, n? (n*—1) where R is the rotation of the plane of polarization and n the index of refraction. Experiment showed this true for bodies, group by group, and while not wholly verifying the theory yet it indicated that he was on the right path and pointed the way for further progress. The next step was the study of rotary magnetic dispersion. Verdet had shown that the rotation is nearly proportional to the square of the wave length and that the product of the rotation by the square of the wave length slowly increases from the less to the more re- frangible radiations. Becquerel divided these results by the factor n* (n*?—1), and the result became very nearly constant, indicating how closely his theory as to the connection of ether and matter was connected with these phenomena. Verdet noted that In magnetic media the rotation of the plane of polarization is inverse to that in diamagnetic bodies, and that con- sequently there is a difference between magnetism and diamagnetism. For Edmond Becquerel it did not seem so; he believed, rather, that diamagnetic bodies were less magnetic than the vacuum; magnetic ones more so. Henri Becquerel tried to show that the phenomena sup- ported his father’s views. He verified the observations of Verdet, but he showed further that magnetic and diamagnetic solutions behave very differently. In the latter case, the action of the diamag- netic molecules is so weak that the rotation is proportional to the concentration. With the former, however, the magnetic action is so strong that the reaction of the molecules upon each other is notice- able. For instance, with the perchloride of iron the rotation in- creases faster than the concentration when the latter becomes great enough. Becquerel verified again the experiment that with mixtures of iron filings and an inert powder the magnetic field increases more rapidly than the number of iron filings. _ Becquerel now asked whether a gas should not have a measurable magnetic rotary power. All the earlier attempts to show this had been unsuccessful. Before making the apparatus adapted to show it 172 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. he needed an idea of the size of the effect which he might expect. Sime 0.2, approximately, used with gases The preceding law, aE (ne =T) of which the refractive indexes are known, shows that the amount of rotation should be very different from one end of the spectrum to the other and of the order of 0.0001 of: that due to carbon bisulphide. So with an apparatus having a magnetic field 30 meters in length he expected a rotation of five to ten minutes of are. Faraday had proved that the effect may be increased by repeated reflections of the light across the magnetic field. Becquerel employed this device in an apparatus about 3 meters in length to measure the rotary power of gases and their relatively great rotary dispersion. Oxygen was found to be abnormal. Its rotary dispersion is ex- tremely small and perhaps anomalous, the green giving less rotation than the red. This behavior may be compared with the well-known magnetic properties of oxygen. Carbon bisulphide furnishes strong evidence in support of the law, for in the liquid state the constant is 0.231; in the gaseous, 0.234. : Becquerel naturally searched for applications of his theory in the world about him. He looked for the action of the terrestrial mag- netic field upon hght, and with carbon bisulphide observed deviations of the plane of polarization of about half a degree. But a new ques- tion arose, Does the terrestrial magnetic field deviate the plane of atmospheric polarization, which, according to theory, must pass through the center of the sun? This study, requiring measurements of high precision, showed that the plane of polarization undergoes a daily oscillation about the theoretical plane, due for the most part to diffuse light, but there is a small residual variation caused by the earth’s magnetism, 150 kilometers of air giving a rotation of about 20’ of arc. This elaborate series of experiments would not have been complete had the practical side been neglected. At the congress of electricians in 1881 Beequerel proposed to measure electric currents in absolute units by means of the rotation of the plane of polarization by carbon bisulphide. He showed that this method is free from the perturba- tion at the ends of the magnet, the rotation formula being R=K.42NI. By various experiments, made by the deposit of silver, the constant, K, was found equal to 0’.04841 at 0°. This gives a method of constructing a secondary scale for the ampere, precise though difficult in practice. To return to the theories. which had furnished motive for all these experiments, Becquerel combined his ideas in a theory of the mag- netic rotary polarization and showed how analogous results could be WORK OF HENRI BECQUEREL—BROCA. i S reproduced mechanically if a transparent body could be turned at a speed of millions of turns per second. In this complete series of researches, conducted by Becquerel between his twenty-second and thirty-fifth years, we see the develop- ment of all the qualities of a true investigator—the directing theo- retical ideas, the consummate experimental skill, the discussion of all the interesting results, those which concern the cosmical conditions of our existence together with their practical applications, and, finally, the theoretical coordination. This work, completed at 35, ranked Henri Becquerel as a master and gave cause for the glorious career which opened before him. At the time of these recondite researches he was preparing others, all tending toward the study of the constitution of matter. They were to treat of the absorption of light and of phosphorescence. These led him to the discovery of the new rays. Let us examine next his work on crystalline absorption. While examining the absorption spectra of various crystals he noted that the bands disappeared for certain orientations of the luminous vibra- tion. Pushing further the study of this phenomenon, he saw that in all double-refracting crystals having absorption bands similar phe- nomena occur, and that the absorption in general is symmetrical about three principal axes; the more complicated the crystalline structure, the more complicated the law of absorption. There is, however, one general law binding them all. The bands observed through the same crystal have invariable positions in the spectrum; their intensity alone varies. In uniaxial crystals the phenomenon is symmetrical about one axis. The absorption spectrum, in whatever direction observed, is formed by the superposition of two series of bands, one corresponding to the vibration normal to the axis, the other to those parallel to it. For every ordinary ray—that is, for every ray normal to the axis—the absorption spectrum is the same for the same length of path. For every extraordinary ray of which the vibration is orientated in the plane of the ray and the axis the absorption spectrum is as if the two components of the ray normal and parallel to the axis individually suffered absorption and then united upon emerging. In biaxial crystals one law is common to both orthorhombic and clinorhombic crystals. Each band has three axes of rectangular sym- metry. When the Fresnel vibration coincides with one of them, the absorption band is at a maximum; with another, it has a mean value; and with the third it is generally invisible. In orthorhombic crystals the three directions of absorption coincide with the directions of sym- metry of the crystal. In clinorhombic crystals the phenomena are more complex and interesting. The axis of symmetry is always a 774. ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. direction of principal absorption common to all the bands, but the other two principal rectangular directions of diverse bands of absorp- tion may be variably orientated with the plane of symmetry, g,. In certain crystals these directions depart very little from the principal axes of optical elasticity, in others they may make with these axes very great angles, reaching sometimes 45°. Becquerel gave to these directions the name, principal directions of anomalous absorption, and inferred from them important consequences. These phenomena occur in crystals containing the rare earths and are probably due to the complexity of the bodies which form the crystals. De Senarmont had already shown that if we crystallize mixtures in variable proportions of the component substances, geo- metrically isormorphic but with the optic axes differently orientated with reference to geometrically like directions, we can obtain a crys- tal having any optical properties whatever, the resultant emergent vibration being due to the resultant of the partial vibrations travers- ing the various crystals, the symmetry of the total system depending upon the portions of each component. So in apparently like crystals the absorption may be wholly different, each component crystal ab- sorbing certain radiations independent of its neighbors and there may be no relation between the axes of absorption corresponding to these bands and the directions of symmetry of the crystal. If certain crys- tals have principal directions of anomalous absorption, it 1s because they are such mixtures of crystals. Crystals containing didymium show the necessity of admitting its division into neodidymium and presodidymium. Demarcay was able to separate the distinct ele- ments in presodidymium, the existence of which Becquerel had thus shown the necessity. In neodidymium there are bands which char- acterize complex crystals. This method of analysis can indicate bodies existing in a crystal which are destroyed by its solution. If, having noted all the absorp- tion bands in a crystal of sulphate of didymium, we dissolve it, the spectrum of the solution is notably different, certain bands have dis-_ appeared, others have suffered displacement, while yet others have remained unchanged. The bands modified are those which in the crystal were marked by these anomalies and the variations may be explained if we admit that there exists in the crystal such a mixture which is completely destroyed and transformed by the water. The separation of the rare earths is very difficult. They are very numerous and distinguished from each other only by extremely small variations in their physical and chemical properties. It is generally almost impossible to purify them. It would be very valuable to be able to seize, by some optical process, in the heart itself of a mix- ture, a crystalline body which shows this anomalous absorption and which, the moment the body is dissolved, disappears to take place as WORK OF HENRI BECQUEREL—BROGCA. 115 another compound. It would be a true method of spectrum analysis which could be employed in researches relative to the rare earths. After having shown upon many crystals the fruitfulness of his method, Becquerel closed his research in this line by, as usual, reuniting into a theory the facts observed. The intensity of a ray after having traversed a unit thickness of a crystal must be i= (a cos.2 a + 6 cos.” B + € cos.? y)? for a given wave length, the ray making the angles a, 8, and y, with the principal absorption axes, the intensity observed along the three axes being a, 6, and c. But there are cases where two absorption bands are superposed in the same part of the spectrum having different principal directions of absorption. Then the photometer measures must be represented by the product of two expressions of the same form. Thus we may have an asymmetric curve for the intensity as a function of the angles a, B, y. This takes place in epidote, and Becquerel was able to explain the apparently paradoxical results of Ramsay in making photometric measures for various orientations in the plane, g,, of epidote. We see in this series of researches the same qualities of mind present in the earlier one; extremely delicate experiments directed by theoretical ideas and the final embodiment in a theory rendering numerical account of the observed facts. The problem brought to this point had no further interest for Becquerel; he left to others the patient work of applying his methods. He himself started on a new path, one already laid out for him, which, in a sense, was an heritage. Edmond Becquerel had already made discoveries upon it of the first order. In phosphorescence Henri Becquerel found a sub- ject well adapted to his trend of mind and where his radical ideas could bear full fruit. We find again the double line of work, the theoretical and the practical, side by side. He showed the first in establishing a new method for the spectroscopic analysis of flames, the other in discovering two distinct laws: First, the law connecting the radiation engendering phosphorescence and that emitted from the phosphorescing body; second, the law connecting the diminution of the emitted energy with the time. This series of experiments is also of the first rank, for the study of the constitution of matter for phosphorescence is certainly intimately connected with molecular resonance. Phosphorescence results from selective absorption, but the nature of the, radiation is such that a purely temperature con- nection between the phosphorescent emission and the nature of the body’s absorption is an insufficient explanation of the emission, which is itself selective. These phenomena seem related to those of the selective emission of incandescent vapors, and so it was natural to look for laws analogous to those governing the luminous emission of gases and vapors. It is true that the molecules are less free in solid 88292—sm 1908——50 776 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. phosphorescing bodies than in gases, and the light emitted less simple; yet. Becquerel was able to unravel definite relations. Edmond Becquerel had already shown that if the infra-red rays strike an excited phosphorescing body the phosphorescence is de- stroyed, just as it would have been had the temperature of the body been raised. The extinction is preceded by a temporary increase of the phosphorescence, as if the stored-up energy was given out at a greater intensity during a shorter time. Generally the two. phases occur so rapidly that the final extinction alone is appreciable. Ed- mond Becquerel had thus commenced the study of the infra-red of the spectrum. Henri Becquerel resumed this study, making many important advances. He studied the solar spectrum by means of phosphorescence and described in this infra-red portion unknown or little known bands between the wave lengths, 0.76 and 1.9». Abney, by direct photography, had gone as far as 0.98». Langley with the bolometer had explored a much greater region and had recognized the more interesting of these bands of Becquerel. But in the region, relatively small to be sure, where the phosphorescent method is applicable, it could then detect finer lines than the bolometer. Bec- querel studied new absorption and emission spectra; he showed that the liquid-water absorption nearly coincides with that of atmospheric water vapor; that the compounds of didymium and samarium have characteristic lines in the infra-red which may serve as standard marks; finally, he mapped the characteristic lines in the infra-red of the incandescent vapors of potassium, aluminum, zinc, cadmium, lead, bismuth, silver, and tin. While some substances lose their phosphorescence nearly uniformly over the infra-red, with others the extinction is unequally rapid in different regions. The extinction is produced under the influence of definite radiations, often to the exclusion of the neighboring regions, so that the spectrum consists of one or more bands where the extinc- tion has been active, separated by regions where it has been either much smaller or nil. Under the influence of the infra-red radia- tions the phosphorescence varies in color with the time. This may be noted in the phosphoroscope. So even in the various infra-red bands in the same substance it was found that the color can not always be the same. It is interesting to correlate these facts with the very similar be- havior in the violet and ultra-violet. The ensemble of the bands of excitation, of emission, and of extinction must be connected by anal- ogous formule with the various radiations emitted by incandescent vapors, for both are intimately connected with the vibration periods of the molecules. The most remarkable phenomena are shown by the compounds of uranium, and it was the study of these which led to Becquerel’s dis- WORK OF HENRI BECQUEREL—BROGA. wir covery of radio-activity. Uranium forms two distinct series of salts. Edmond Becquerel had shown the phosphorescence of one set, the second does not phosphoresce. Henri Bacquerel soon noted that the latter salts have characteristic bands of absorption in the visible and the infra-red spectrum. Studying further the compounds of the first class, he noted that most of them phosphoresce as had already been shown and that they have in general a discontinuous spectrum of seven or eight bands or groups of bands between the C and the F lines; these bands vary according to the nature of the compound. The compounds have selective absorption bands which correspond to all the radiations which will excite the phosphorescence. If the body is excited by the light of the wave length of any one of these latter bands it will give out its total emission spectrum of all the wave lengths proper to its phosphorescence. Becquerel formulated this law: The difference in the oscillation frequencies in passing from one band to another is a constant, the bands of absorption continuing the series formed by those of emission. The latter seem to be the sub- harmonics of the former. Often one or two of the less refrangible absorption bands coincide with the more refrangible ones of emission. It seems probable that the absorption forms some kind of synchronism with the periods of the emission, but it is not expected that they will be found to be subharmonics. They are essentially distinguished from incandescent vapors in absorption. The ordinary theories of reso- nance are incapable of explaining them, but the simplicity of the law which binds them gives hope some day of the possibility of a mechan- ical explanation. It is remarkable that the second series of uranium salts which do not phosphoresce but seem to degrade into heat the selectively ab- sorbed radiation, should have bands which follow with a notable regularity the same law which holds for the emission bands of the other series. The bands have not, however, the same relative intensities. We have just seen the theoretical difficulties offered by these phenomena. Edmond Becquerel had already studied and formulated the variation of the intensity of the phosphorescent emission with the time. His formula, however, held only for very short periods of time. Nor was the one derived by Wiedemann sufficient. The formula, i=%,e-*, was deduced theoretically from the hypothesis that the molecular degradation of energy is proportional to the velocity of what we will now call electrons. Becquerel thought it better to make this degradation proportional to the square of the velocity and so i + bt total phosphorescence intensity did not agree with this, Becquerel, remembering the changes of color, thought it possible that a similar obtained the formula 7= ila p. As the photometric measures of the 778 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. term ought to be used for each band, so that if there are two bands in 2 2 the spectrum the formula becomes i=tl( sty) + sa) ; He verified this formula in several cases, so that it seems proved that the phosphorescent phenomena follow a law probably adaptable to some mechanical explanation but much more complicated than acous- tical resonance or other analogue to which we are at present ac- customed. From that moment, for Becquerel, phosphorescence became a source offering mysterious properties, the unraveling of the secret of which would embrace a multitude of new discoveries. RADIO-ACTIVITY. When the discovery of Roéntgen was announced, Becquerel, like many others, at once tried to see whether phosphorescent bodies emitted photographic or phosphorogenic radiations which would traverse opaque bodies. And here we may still better appreciate the subtlety of Becquerel’s mind. In the midst of a maze of seem- ingly contradictory facts, he knew, by his marvelous intuition, how to avoid the paths to error and to take that which would lead him by infinitely small manifestations to the fundamental phenomena of radio-activity, that immortal discovery which has already revolution- ized modern physics and promises to lead the physics of the future into fields as yet unrealized. The biography now becomes difficult. It could be made nothing more than the renumeration of Becquerel’s astonishing discoveries without explaining the extraordinary conditions under which they were produced. Those physicists who may read this will recall that fever of excitement among men of science which followed in 1896 the anouncement of Rontgen’s discovery. They will recall, too, the first experiments of Becquerel, which raised the doubts of the older school and the curiosity of the younger. Then Becquerel, aroused by the daily disclosure of new truths and by the increased publication of his works, accumulated in three years a mass of re- sults that confounds us. And we should also note at this time the devoted collaboration of his assistant, M. Matout, in whom he inspired admiration as a man of science and an unlimited personal attachment. Ordinary phosphorescent substances give off no emanation capable of traversing black paper. But it is not so with the compounds of uranium, whose peculiar properties Becquerel had already recorded. By first covering a photographic plate’with black paper and placing over the latter a salt of uranium excited by direct sunlight, he suc- ceeded in obtaining an impression upon the plate. But one day the sunlight disappeared a moment after the exposure had been started WORK OF HENRI BECQUEREL—BROCA. 779 and the apparatus was left in the dark. Later the plate was de- veloped and the impression was found as strong as if the sunlight had struck the salt. Upon trying the experiment again without sunlight the same result was reached as if the sun had been used. Although this uranium compound, which had been prepared some time, was now kept in the darkness in a lead box, yet it still continued to give the same results. The discharge of an electrified body under the influence of the uranium emanation was next tried. This was at that time the only process known which would give quantitative measures of this strange power. Then it was necessary to see if the phosphorescent state was necessary Tor the newly found emanation. A nitrate of uranium crystal, whether in solution or melted in its water of crystallization, gave the same effect as when in the solid state, although in neither of the liquid states would it phosphoresce. An attempt to see whether bodies near such active compounds became active by a phenomenon analogous to phosphorescence was unsuccessful. It was several years later that the power of radium enabled M. and Mme. Curie to show this and the profound difference between this new phenomenon and luminous phosphorescence. Some odd results, not yet understood, led Becquerel for a moment to erroneously believe that the new rays were ordinary radiation. But he soon saw his error, noting that the propagation of this new emanation took place as well across pulverized matter as across solid, continuous bodies. Since all the compounds of uranium, whatever their chemical or physical state, showed these phenomena, it was therefore natural to attribute them to the uranium itself. Pure uranium was tried and gave more intense results than the salts. It was now made evident that neighboring bodies became the source of a secondary emanation as long as they were struck by the uranium discharge, but that the phenomenon ceased as soon as the body was removed from the presence of the uranium. By pushing the experiments with the electrical discharge still further it was shown that the air is rendered conductive and remains so a few moments and that this plays an essential rdle in the phe- nomenon. Air, active under the influence of the uranium and blown upon an electroscope actively discharges the latter. If ordinary, inactive air is blown between the uranium and the ball of the electro- scope, the latter is discharged more slowly. The emission seems independent of the temperature of the uranium. The temperature of the gas, however, modifies the discharge. In order to regulate this method of measuring the emanation, it was necessary to find some law governing the discharge under the varying potential. Becquerel established a limit of the velocity of 780 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. discharge for potentials above 300 volts; Rutherford later called this the “saturation current.” Finally, by studying the modification of the velocity of discharge produced by the interposition of lamina of different substances, Bec- querel showed the complexity of the emanation emitted by the ura- nium. From now on these radiations were called “ Becquerel rays.” All these results were verified by Rutherford, who extended them, characterizing by their absorption two classes of rays: The a ‘ays, very active and greatly absorbed by the air; the £ rays, less active and much less absorbed. He applied to gases, rendered con- ductive by these rays, the theory of ionization, which J. J. Thomson was then developing, and showed the identity of the phenomena produced in the air by the Becquerel rays and the Rontgen rays. While Becquerel’s results were being verified in England, M. and Mme. Curie in France and Schmidt in Germany were searching for this emanation from other bodies. Mme. Curie and Schmidt dis- covered it simultaneously in thorium. Mme. Curie found that all active bodies contained either uranium or thorium. She determined by the quartz-piezo-electrical method of Curie that each compound of uranium, whatever its history, possessed the same power of discharg- ing—the same radio-activity—using the name adopted by Curie. The two Curies then tried to isolate the body endowed with the property of radio-activity ; and by an immense amount of work, using Becquerel’s rays and Curie’s piezo-electrical method in their analyses, they finally discovered polonium and then radium. Using pure uranium as the unit of radio-activity, radium chloride has an activity of 1,800,000. Becquerel could now continue his researches with the extremely active products placed at his disposal by the Curies. His earlier experiments he repeated with polonium and radium, and showed, by his absorption tests, that polonium emits an emanation different from that of radium. Utilizing the admirable collection of phosphorescent compounds left by his father, Becquerel did not delay in establishing several new properties of the emanation from the new products, showing that each of them emitted a complex bundle of rays excit- ing in a special manner the diverse phosphorescent substances. By his absorption method he showed that the very penetrating rays excite the double sulphate of uranium and polonium and that the most penetrating rays excite the diamond. Finally, he noted that the ‘adium emanation can give back to bodies the property which they may have lost of becoming phosphorescent by being heated. This may also be accomplished by means of the electric discharge. Becquerel noted that the radium emanation gives to chlorine a phosphorescence much more persistent than that produced by ordi- nary light, and compared this with the similar result produced by WORK OF HENRI BECQUEREL—BROCA. 781 the cathode rays as shown by Sir W. Crookes and Edmond Becquerel. He compared the chemical phenomena produced by the cathode rays and those which the Curies had observed with the action of radium upon glass. It was but a step to Becquerel’s examination of the effect of the magnetic field upon the emanation. Giesel, Meyer, and Schweidler had already obtained some results along that line, but they were unknown to Becquerel. Becquerel’s observations, when completed, were more profound, more fertile than those of his predecessors. He observed the important fact that the radiation, deviated lke the cathode rays by the magnetic field, suffers a dispersion. This showed that the emanation is composed of electrons having different veloci- ties. At the same time, working with an electrometric method, the Curies showed that in the emanation from radium there is an unde- viated part much more absorbed than the other rays, thus giving a new distinction between the a and £ rays of Rutherford. Polonium according to Becquerel gives only the nondeviable rays. But at the same time Villard showed that in the nondeviable bundle there exists, besides the very absorbable a rays, a set, extremely transmissi- ble, which he called the “ y rays,” and which are identical with the Roéntgen or X rays. The remarkable studies of J. J. Thomson on the cathode rays re- corded that from the trajectories of the electrons in a known magnetic ; : : Mv : field we may determine the quantity —-, where m is the mass of the e electron charged with a quantity of electricity e, and having the ve- locity v. The trajectory of the rays discharged normal to the field Mm should be a circle whose radius R = —~, where H is the intensity of é the field. It was necessary to see if the radium rays gave trajectories . me . whose radius equaled —~ analogous to cathode rays. Experiments é showed this to be true and that all the preparations of radium or its salts gave the same kinds of rays. It served also to show that the dis- persion in the magnetic field could serve for the study of the pene- trability of the various emanations, for the more deviable the more penetrating are the rays. The images obtained by placing various screens separating a photographic plate from a morsel of radium in the bottom of a lead trough, and all placed in a magnetic field, al- lowed, by means of the images upon the plate, a determination of the limits to which the emanations penetrated the screens. Moreover, the radii of curvature were easily calculated. Knowing the field H, the products RH could be easily deduced. These products, equal to m°’ lay between 637 for copper and 3082 for lead. Admitting veloci- é ties analogous to those of the cathode rays, the values,“ could be ap- € 782 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. proximately found, showing whether the emanation should have a sensible electric deviation. Becquerel made the calculations and pre- pared the experiment at the same time that the Curies demonstrated directly that the deviable rays of radium carried negative charges. On March 26, 1900, at the Académie des Sciences, he published the confirming results.- Dorn independently published the same results, depending on the calculations of Becquerel. Knowing the radius of curvature for a cathode ray in a known . ° ° . ° é magnetic field and its electrostatic deviation, we may calculate — 2 J m and vw. When his discovery was well assured Becquerel published figures obtained from the absorption in black paper, giving = é A z pt lO. and 182 X10", very close to the last given by ” : e : Kauffmann. While Becquerel struggled against his insufficient means for con- structing the necessary in vacuo apparatus, Kauffmann completed ex- . . : é . . periments with sufficient accuracy to conclude that op Varies with the velocity—that is to say, that mass, the constant which has seemed so well established since the time of Newton, has no absolute existence and that we can consider its coefficient as constant only with veloci- ties infinitely small compared with the velocity of light. We will say nothing further on this aspect of radio-activity. It now passes out of Becquerel’s domain. Indeed before the flood of foreign investiga- tions which furthered his results and before the new results secured every day, he had to leave to others the experiments for which he had neither the material nor the means. After the a and the £ rays had been clearly distinguished by the experiments already stated, it was questioned whether the former are only slightly deviable or not deviable at all. Rutherford per- formed an experiment from which he concluded that they are slightly deviable but his conclusion was too involved to carry conviction. Becquerel took up the question, using accurate measures made upon his photographie plates, and was able to establish a weak deviation undoubtedly, the a rays forming a pencil clearly defined and not showing any sensible magnetic dispersion. These rays are analogous to the canal rays of Goldstein. The curvature of the a rays seemed to augment with the length of path in the air. Although the great absorption of the rays by the air made difficult the simultaneous study of the magnetic and electric deviation, the problem was solved by Des Coudres. The experiments of Becquerel and of Rutherford proved that the change of curvature in traversing a thin sheet of aluminum is due to a noticeable retardation of the charged corpuscles. WORK OF HENRI BECQUEREL—BROCA. 783 To Becquerel it seemed due to an augmentation of the mass, to Ruth- erford to a diminution of the velocity. Becquerel found that polonium gives rays that are identical with the a rays of radium. An exhaustive study of uranium, even in vacuo, disclosed no a rays, but it was found to emit very deviable B rays—that is, rays of small velocity. The beginning of these studies had shown the existence of second- ary rays produced by the bombardment of another body by the Becquerel rays. Further study showed that all radium rays do not possess this property. The most rapid corpuscles traverse aluminum and suffer no modification. Those for which RH=3.436 are the first to suffer change and produce the secondary rays after passing through the aluminum. When RH<1.500 they are completely absorbed by the aluminum and give noemission. The secondary rays are deviated like the primary in an electric field. It was these secondary rays which produced the intense impression on the photographic plates of Becquerel. The very penetrating emanation traversed the lead, producing the secondary rays which then affected the plate. These rays produce the augmentation of the impression along the screen hit by the Becquerel rays. These experi- ments remade with polonium showed that in time the secondary rays due to mica indicate a much more penetrating emanation than that ordinarily noted from polonium. Becquerel studied the transformation of white into red phosphorus under the influence of these emanations and showed that the slightly penetrating rays produced the essential part of the action. The a rays could not be tried because of the necessity of protecting the radium. . The fertile success of the ionization theory made it interesting to see whether analogous phenomena took place in solid dielectrics. J. J. Thomson showed that it occurred with the X rays. Becquerel showed that liquid or solid paraffin became conducting under the action of the rays. That the action continued constant in the same apparatus during a year indicated that it took place even when the paraffin had reached its permanent state. At the time of these discoveries the Curies were bringing to notice induced radio-activity, and Rutherford, the emanation of radium with its curious properties, the exhaustion of the solution which gave the emanation, and the recovery of the radio-activity after a certain time. Thorium had an emanation of its own. None could be isolated from uranium, and yet Becquerel showed that certain phenomena appeared to indicate one. Sir W. Crookes showed that by fractional crystallization of the nitrate of uranium in ether the foreign matter became reactive, the nitrate less and less so. He attributed this to a new body which he called uranium-X. Becquerel showed that these 784 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1908. phenomena follow the same laws as those of the salts of radium in solution and that the nitrate crystallizes reactive after a time. It seemed then that uranium has an emanation. He showed that the double sulphate of uranium and potassium is spontaneosuly luminous in the dark lke the radium salts, only the effect is far smaller than was expected. Becquerel proved that the phenomenon of Crooke’s spinthariscope is due to the cleavage of the hexagonal blende under the bombardment of the a rays. Becquerel considered with Curie that the radio-active phenomena are due to a constant evolution of the atom, the atoms of the active bodies being variable and constantly destroyed by explosions. The débris may be in part of inert matter, partly of groups of electrons or single electrons which constitute the various emanations, the a and the £ rays, and communicating to the ether concussions (y rays). The corpuscles remain scattered in matter or in space.. According to this theory the emanation may be regarded as a group of electrons carried by gases or matter. Perhaps, as Filippo Re believes, we may consider the radio-active atom as a condensing solar system; perhaps with Perrin, as a solar system from which the exterior planets are escaping. Becquerel said of these hypotheses: ‘“* Re’s may be consid- ered of equal worth with the inverse hypothesis; they both deserve the interest due attempts to connect by common laws the infinitely small atom with the infinitely great universe. DIVERSE RESEARCHES. Along with these great problems, in which Becquerel held such a leading position, he worked on certain other problems which the greater ones had temporarily replaced: His research with Edmond Becquerel on the temperature of the sun; then in 1879, on the mag- netic properties of nickel and cobalt; then he showed by interference methods that in the propagation of radiations across rotary-polariz- ing magnetic fields the right and the left circularly polarized com- ponents travel with different velocities. Later, when the Zeeman effect was discovered, he took up his latest ideas relative to the action of the magnetic field upon hght and showed the connection between the Faraday and the Zeeman phenomena. Then, in collaboration with Deslandres, he studied these phenomena experimentally, particularly with iron. They showed that, in this case, certain rays are unaffected, some give triplets, other quadruplets. The ray, 0.3865 p, is anomalous; the two extreme rays are perpendicularly polarized to the lines of force, the other two parallel. Becquerel also showed in a beautiful way the anomalous dispersion of sodium vapor by the classic method of crossed-prisms spectro- scopes, but with a very original disposition of the apparatus. He WORK OF HENRI BECQUEREL—BROCA. 785 produced a prism of sodium vapor by means of a small platinum trough held over a yellow sodium Bunsen flame. He received the spectrum of white light formed by this upon the sht of his grating spectroscope and the hyperbolic form of the D lines indicated the phenomenon of the anomalous dispersion. We will close this short notice of Becquerel with recalling that both he and M. Curie were the first to suffer the painful effects of radium upon the human body. Becquerel, by carrying in his armpit for several hours a preparation of radium, contracted an ulceration in his side which was very long in healing, and at another time he received a noticeable pigmentation. With Curie he published his observations at about the same time that Curie had suffered the effects upen himself. These two great men were thus victims of the dis- covery which led them both to glory, and perhaps the weakness caused by their injuries was partly to blame for their premature ends. CONCLUSION. And now that I have so hastily reviewed these great accomplish- ments, may I be permitted, as a friend of Becquerel and of France, to express a heart-felt regret. Since Henri Becquerel built his work with the poorest of scant material, the regret which I wish to express is that so great a man had not at his hand the credit, the equipment, and assistants found in so many foreign laboratories, which would have more often allowed Becquerel to arrive ahead of others at the goal of the fertile paths which he disclosed. AND Dem CG levie lain Gi sm = See es mares Sie RSIS yaa Msig er Ne ar ey 8 apa Sete 15 IAD both arles: Gees he 3 ers eee yes ee ae ee overs eae x, 2, 21, 72, 81, 84, 100 Abbot, Charles G. (Solar vortices and magnetism in sun spots)......--------- 321 2/0 0] OSB fee Spee tena ae Aa eas a On ae eg PIR ene een Ce 27, 38, 42 AC COUMUS RAC Nir Ola ee eee ei epee ree are ney oe eee yO oe ee 89, 92 ERROR CE HMONG: Sos 3525 esac Tet aeene oapntins nao he ee nee a 93, 96, 99 Adams, George I. (An outline review of the geology of Peru).......-.-...-.-- 385 PATEL ET CEU is ofan eet Se ere ee hese, Sad Ge Es Se eer 29,37 PACU AINTS MV Vis [eprom are ayaa ee sre ete Ne a 2 Sn Ae et A ae - ae ayne aae Taxed BOI CE MEO NDUIN Pay toc Prete oe 2 weep EON ese ete P= es a mE IX, X 220 4161 765.78 PN@ Tale Ava Oat OU 22 et aye Loerie Ses sn tos eee Sy yc trent tee oe ee creeped oe 8 Merousiiies. Malitary (SQUICN) 2.2.2.2 stwcecc—sas aoe Ae eee ees oak ee eee eee 117 Ne APHE aE OMIS (WW AICOLL) = etre Se arte Seis oe aoa oo a Seta ee a oe ee 80 Aeriemiinres Department Ole 05-5 ooce0. eee eRe es eee 28 eee eee 27 Seetetary of (Member of Establishment)... .2----22., -52 2005-5 -cce eee Exes Air pacs'of the pigeon (Von Lendenfeld-Miiller)......<..<-.1..2..- 1: 2seceses 14, 80 Air temperatures at great heights (Rotch-Fergusson) ..........-......--------- 14 AnH TOlen nozzle. (Bradley) ..5-— 22-2 Shee toes oot ania eas Seamer 13 Miaskan expedition (CiiInOre) sss 5262 ca5s5. es Saas ws Sak ae aaa See eae 10, 82 ‘Alaskantcame sprote ction Oles—.sect esos caaae sis ee se aoe eee eee 104 PRE ARICA CHV LING cee See ee eS ae Doe one te a eee 80 PAIRS Wee) 15 ag Bs epee ee ps ae loge hie a a ye cet 68, 71 AW ocibons A eCTIGAN: (LvPESD) ae see as ce hae tas, scion cia's'c a SEES See Oe 18, 82 PRM COLO Ok (WAILNS heen oie EIU isi S la yate ae sie ales Scars ne 2 10 fe STE TEED CHAN 0 UTS Oe PROS ORES Se ee ee a ee TE eh cS Co Re 22, 50 AIMIeLtcane stor calencsoclatlOWMsseemere ses ese ss ince =e See See ee 20, 84, 102 AmericangnluscumoreNabunral sHIStODYeres --s-n- + 5-22 es es one ee ee ee 40 Americanists, International Congress... ....-..---2---2-522252-<:- eat ae 25 etLOn es NOUN LAT TEMIOM ota.) ot sissies sais nays oe we stesso ee ee Sos Teen 388, 422 ANTI IRO SS JOO NAS Rr oie is ss SRS RE ed 208 ae RE yee ite meee IME EN ie. 3 ie) PAI CTE Wee E ple eee sae ears ote Seve weirs ah clterehs oS nb = Se einist eke a eee eee 16 HPO wEe Wallace Ce: ( DEMUCRE 2 .cescn hasoee ac ces nyse iarac Aas sto > oo baer 98 PEI Cee esta ERCO CM) eta wetten «woes cea 3 ie ote) wien nl ots eo pet arse ate eee a 1X, 97 ASIP UETEO REE THOR ee ic,5 aes ye is ere Caen orn See a ae ee SO cies Sees 565 Animal Industry, Bureau of......-..- Bee Se ayes Sais Soh oe oes a/4 ae ae ee 40 Antare ite quenmon. (MaAChab)._— sista. 3 22 cls oe ste wk = hae ei oe 451 Appleton, When s.25 0 acee soe neice Fearsome Se a Solos dates Sp sep ee eerie 39 DEO PELSeOHA ye COMPRESS a noms emis aoe ee ese epee ow en ee OOO AT IZON AINE LEOLIUERE eee a ena ee ate oe eee ia eae eee 9, 41, 80, 81 mimi ab, Fenrd, (i HOLOtelepTapiy on a6 s- as = 2s cs ~/4 oa =i = ns ee 197 PETG LGU ALD Mike roma totam Sah ees Saas Vee els ie. s ois ass > anja mee ene 81 788 INDEX. Page. Articollectlonsassec core hems eck aoe eee anes sees loa ee 27, 28, 36, 45, 93 Assistant secretaries of the Institution.................-- 1X, X, 2, 21, 24, 43, 61576; 77 Astrophysical Observatory : Appropriationsiand: CstimaAves teen acre cece cera ok = Sameer ere 5, 90, 103 lint Tsland:S tations: acess see ee eiersionts Aes cies om roe 34, 69, 81, 100 Observations jaceoac ce oo ee eats 2 oie se ee een eee 33, 69, 71 (Orie eee ae eS Gere Meee Hoe aet Seen pene See nan aaa cup OSES xe sPrimGin ea Ota e nm tees oe ae eer tae eee re eee ee eer ieee 20, 102 Publicationss=.-25-.-<- BSF ak haar th oh ee a pee APO CeO ... 1,19, 34, 68, 84 Report ol Secretany.-c-s4-22 =o 2222-52 ane ie ieee tale ee PEPE Ae, 33 Re portiel Director. semen ate eee tee eee ee ee eee 68 imosphere) mechaniesior CADE) =e mee eee toe ae era Re a ee eile 15 Cio phere, 1pPer (EOLC HP lene usSOM)) serene eee aa ler eter 14 IATROTTTUCG Ayer ea Nest (Oba <2) ) Sennen a nee Oe ee Asa ohh eee Sacopeuche.coauECAl es 5 11 Mttonmey=General (Member oi Hstablisiment) seen = 2-2 2-4 ee ee ae eee Px swans, live) acing suena oon (Oeil Gs) st oanpoue sescesoc sho ssescecsre su pesosse Sac 87, 99 AviationvineP rance.(JOUdAIN) soso hone cen es a nc hee ee See 145 B. 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OM aa Sono co eS oto es er a6 4050's 45 dat Yeis Gs piy] Sge seo hes Sei AA Se Ss Sear Roms A erie: Co ct x, 40, 41 Bates is Miseccsecaa-5 sense ks ood San s.c ais se siete Sie aa ee eee eee 89 iBeatrehamnypp: (Why Miss yo ose ae ees ole Ses ale shee ee net eee 45 Becker sGeorge: Wome esnca ta tees se eesti Se ere eer eet 18, 82 iBeequerel Work of (Bt0ca) oer ne re pe ate te eee ee ere 769 iBelimésitelestereorraph ere eit eae ie etek SS eS SA eee 5K [Bie bec) ch eRe COB EE CERO mee Se eerioe ma sede rien 658 abies Seco oe 4,12, 26, 45, 87, 97 Berjonneau is tramsmar tte rie ese ae tee oe eet 205 Berliner ;Bimile tao 0 0 aegis oe ates oo NA) oS ca ts fae oe tO 209, 210 BentsystE ts Vicec stamens sortie facie ate ah ar te tee: Nae ee x BG VERIE Ge. SCDALOT IA IIe ces earl ete ee 38, 41 Biees, Hermann: 25-22 277-3 e ee eee eee eee 13 Birdstotdndra Dewalt) s.-.2-e- ee resent mace nae eae nee ee a 617 Bivalve, Bresh-water (Dall) = 22 -- an ae ate eee ie 81 ‘Blashhield) Mid wine He 22552 asec eee te oe ee eee eee 29, 37 IBléniot aeroplanes. sccm ones ee eaten ee 135, 151, 155, 158 ‘Blondel’ s\oscillograph 32-22-52 eee ee ee eee ee 204 Boas. Wan zee cokes oes x ee nee ate ee RE ee eae ee ere x, 25, 45, 49, 84 Boghaz-Keui excavations (Winckler-Puchstein) ......-.---------------------- 677 Bolometersseeeeenasee Be ieis Senile Be ord is 2 Re oO Eee EEE 34, 69 Bolton,sHerberthll- AE EP Emcee, 2 2 | 106 JRO SV OSES BH tare Sees oe Gee Ce eee PCat ee ager te I Es aS 5 109 1 fhe Fairbanks, Charles W., Vice-President of the United States.............. 1x, 1.92 HaniaaINAClO Plane renwes ere tae cate sn 4 esa se sere a aces 134, 152, 154, 155, 158 Hatrand: Grvingston)so- oases hae Se ss eae sais teil a he ees eee ae 46 ETOMESON, Oo esses se cata eS kee eee ea oe et Se eee 14 Hers (Underwood-Maxon)).< toss 2ccse no nesat on tenis Le ne Sta rn 80 Bessenden, FR; A. (Wirelesstelephony) =: <..).00.05 222 nn 4) ncn med as nye saree 161 88292—sm 1998——51 792 INDEX. = Page. He wikes da Weallers cele v te a aaa in cr es re eet X, 23, 24, 38, 41, 47, 48, 50, 80, 101 Pinanecralistatemve ntsc secs 5 ses yaaa eae aye ete aera etate ia ra deat Uh ey eee ul ae 4, 87, 90 Bashers (Walter de oe seas a do Be ase chai bee ore atpneycia mre ie ws enhs Aa Se ae ea 81 ‘Bisheries sD UPGaAiOlaes cae steers bee aoe steers picts a 2) Ae, § She ied 27, 39, 40 ishierye@ OM OTESS) Ma ceteris eee te eee area pyar Laaem an Sea Dy a See Seen eat 25 Rishess the Anoler (Gull) Sees sac. Sake epee are ane is eee ateret ieee eps Cor eee 565 HletehersMisge Alli cetGee tear ese race yen e atac aoe Cn Aye ea Ree oe er 46 AD xer Ort SUT OTA SAN te Pala iene eT ee geo pLignt Ah ase AUN peut Me eg ec tae 13 SUT Ce Heb limi eh ae Pee ae ace pene ra e a ce Bret, Syereycra oteratae Meer clay =e eet 96 HiveswMuscoideann (le wnsend))\c 22:5 ster 2a Geee eee Seat ae scion 82 Lie el olan uSta bon ante a ub ruen ite seen ee aes pia emg Nga Ai A a 34, 69, 81, 100 lint adamesiMe. fa5- sit as eye ae ees Tee scarier mba aoe ches Namen al WT CY 8 be Hossila@etaceans: (rue) eet as see see os eet aero ne taieha nintar eee mete een ee eh 81 HoseiMolbisks\(ArnOl eres cbn sais salts eee cist ie eae Ace Nhe a eae eae 81 Howie: sGerard joss 2 foro Sey aio itera sores guia ty tot ME UROL RS 46, 49, 50 lowe sb Mos pis 5 Se ciaisin sate sieetel sta\~ ies Ses Seren Se aleve etn cotta eta ert eee x, 68, 84 Brachtenbbero Mccoy See hehe sa cia ke a as ele alee e e teerait ye eee ey eae 49 HrancereAwaa tion did Gourd aim!) ashe ees eee ate ae coeay e eeeaet e 145 Freer, Charles L. (bequest)....-.-...---. Pies Wath ok Be Lacs kas 8 a ae ere eas 45 HullereChictusticesMenwWe(Chancelllon)esss--se4e easel eee eens saeee Ix, 1, 92,97, 101 TEU Porat eco) oU Gl isisg estes MI Ouey eS ceca a ane a ener eats ote U atte ge mA al Oya ae CS 13 G. Garneld, James) Re (Seeretary of the Interior) 2222-2. ecne soe eee eee one ipl Garner «PVOlOssOns a sui 6 iis ees tele a eset ata laa oe Se crore ate jane eve Tee tah orate arene cee 227 Gates sMerrillhiseisy cnet te wee eeu feepernen Sten ee eine ene wi tne ey ae ee 46 Gatsche tan oe ok ate cle nete nelord chatefe Matt aspera cia vaha ent ee acetal rata ea 46, 51 GearewRandol ph [si 2 cocks sree eesti eciticn ete eich tanrle see ee ee cee eee x Genos-yBritish Cemetery ataccececececes ceciscisine cic eee e |e mee rae eee 95, 99 Geolovicalisurvey, United States thet. hack ote cen ees cee eee eae 27, 40 Geology and Paleontology, Cambrian (Walcott)..................-------- Ue ksh, Bil, (eve Geology; ot Peru(Adams) (oc. 2M eek ose code see bocce monte Beeaoeeeiee eye 385 Geology and Uranium: (Joly) ac. fae he ee Se lee Se eae eet vererey ante 395 Gerard aWallliarine yy isi ace eek SO DEON ER ce eee eee ere eres 46 Gidlleyadiew Wit Sa se oes See chemise: faints METS Fe ere See ra scree neta ee neon 41 (Guittssandstoangesee- eee eee Ge AONE as SATA RSE ta eae os 27, 36, 64, 66, 74, 94, 95 Gall Sse sua Ge y.s Wikre pa ta srctera see ee ac sche ta ie EP ey SPR eee pase ee x Gilleith cod oresstee sce ccm ecies ase Sa eee eee Bathe Aietenines 24, 80, 81 Gill, Theodore (Angler fishes; their kinds and ways)......-.....----.---- ai222 (669 Grilanaione 4 © AW oe etree oe eae ee Le ee lt doa UN Eee Oi go ee ee 10, 40, 41, 82 Glacierstol@anadianeockies!(Sherzen fesse-- eee ee eee rer neon eee eee eee 1/5 08) Goddard s1Pei Baker ie aoe crue a mieeene ree een eee eM L eye ar Ne epee 46 Gold swith a Sees ere eee ee BAER AU ER CE ee ee ee Bx Gramophonet(Reddic) vee tee cae Se ey ar Ot ora 209 (Gage bol cigcrseceiteh a Bes Mea AR a ACCS d SEIS RIS ea aa ee Soe LO; 12512; 03; Laas Gray; George (Regent) Wiens .ote ence yo se eye Geet eee cpl Se Ne Nes arena ane Ix, 97 Greece, Malaria aniq(Ross)t2 sss. o Ue es eee See ee es ee 697 Greene’ Hdiward Wie have os BEE RE RES ey Oe eee 20 Gregory, J. W. (Climatic variations; their extent and causes)............----- 339 Greenough’s Statue’ol Washington). 0.. 222520 ee. occ ne ee ee eee eee 28, 37 Grinnell, George Birdy. 5 oe = Sie ik eae oe ee ee een ee 46 Guatemala, ‘New Cactus tromi(Rose)): 52: 2 soy ee ee eee 80 INDEX. 793 Page. "Sr iUa cre) LINN DVB Cite an A mee Meal ee ge 8 Fo Oe a ay RA me Guttmann, Oscar (Twenty years’ progress in explosives)..............-.------ 263 RSL e Dy Min Ht cpupe tere Reming imine ne RACY Se Es dc Vo ee ee 16 180. iEabels Simeon (bequesiy= assent heen omens Owe aire ghia cai: Wyn ogee ae 4, 87 AGC PMN Whee ees arr ane te IE A IC Se hee Gordie Oh sli th ae eae 98 Hieite. CARBO wea oa. soe sain See Ae oe PS cera Ou ea tioee esaong ee SEN ieee pete 25 dT SLSUNS) 1G rerahre ad ge nie net ele ie a SS a SLE Er OME CIS oh RNB oat es 26, 323 alloc kaa Wail amie cs sea eesti ae eae ty SLO Pl ge ks Cire nln OA SR 1. iHarnpachaCollectionrot hossilseasaa = saa eee eee see SEER PUES C7). 27, 40 eral lron.co aves) (DEGUESh) (sae ake Ne oe ea SL ees ieee al res ee 4, 26, 87 1 a (Sts I aVovas Pera 12 [roe Wt 0h ep yews eel AA OS ee ees a SRE gs 2 19, 30, 45, 51, 84 Panning: AU cists MeRSOr Ens, WUlc Op ATIDY re Selo teat Wes se Te ee 38 SB ISUSG 0 jad eo DN RS aR Repel SN ar Se eR COO RV Mi aes OUR Anat sabre tint SYN 2 25, 26 Hawaii, Unwritten Literature of (Emerson)...................----.--- 19, 50, 51, 84 Pci core etal ys tare aren ee Se Severs ee a Sic bh, See aie? a ee ce 27 eletnalygliza (erolessor vile. 6 <6 cen. Se oes oie ees ase Mee ee 141, 143, 162, 245 Henderson, John B. (Regent).......- PSE TS es at Oa ee IX, 91, 92, 97, 98, 99 Henry, Joseph (First Secretary of Smithsonian Institution).................- 161 Sern Wg EPOME Ye Wee tee 9 me ee oi ano ee tere ep ORIEL aah os ips on pe 46 Piereaiiye MAC LOURAL) So vatet ce rec h Cn te ny aa thre SS ore Marana ee 505 He rin Open Ms cosa ss Sate nue eer cae) Sy. CNA MCA cpl tie 28 er 134 1 5 (OSS OG Dat pai see aed oe ees ea ge a Red eam gE BA DDIne CaM MNES hp 20 BG thee ins Nama O Eee te teers Cc 8G. Sen eae teh ee ca ee ene 39 PEW rule) Benet hae eoaeoiets ates Pee bee a teem owe ee Sela 2 eee x, 48 iBlewaiy. eCver COO pena... a= me 5.2025 aie a Sera ese eerie 143, 171, 176, 185 DAP G se Were see ke eee 2 fe Ls Ce ee See Sawai as aoe x, 21, 45 Hodgkins; "Thomas George: (bequest)+=.:.2...~2.~ 252.5. --625- 4,12, 87, 88, 96, 98 JS) hooyeispea\ ylineeh cong! 8 Uae ees are es oie a eee ey Ae X, 2, 26, 29, 37, 41, 44, 50, 52 atolotnammanet (Glan): oats .ccs teeta ces eee ake cee an ase nee meee 17,79 Binueh Walters. cete eS oe oe ee com ce os oe ak as = set euE ee eee Soe 41, 46, 50 SEMI exhd uO) etc eSNG IE ee IE RE ia nie Moen UE Solem e eo es See ae De Howard, Representative W. M. (Regent)...:.......-.<.--.--..---.-. Ix, 2, 92, 97, 101 IN yee as Pee ts a ee RR tee di ie i ail ca er Le Se ee 16 Hein Kan AVES i: ote ete dere ene pe hare he Be Beek ate Bee ESR ak apg Se 41, 46, 51, 84 if ineome and expendiiire (2 Lene eee cdaee anes ae ete cam eth een ene eee 98 rate I edeOt (DEWAR) ke ncscwocis sols ce kate teehee onic eee no te See 617 Interior, Secretary of (Member of Establishment)..................-.----- ix, J, 23 International Catalogue of Scientific Literature: pPPLOpHauow ANG CstiMAtes >. 5 .\22.067/ 2... 22S se ae see ee eee 5, 78, 90, 104 AIC eTe she oiuich’ alee Ra ae om Oe bin oles pede eine eWuaite See ei tee eae x PTGS AL ORION bso 2 ion cia n't aise, otis iss el oro ape ion atari cia te Soe 20, 102 ENC PONG OL PECKOlanyas sasseeeee ctaseer ones as ce ee eee ae a eee eae ree 34 Report of Asustant Secretary =: 5.25... << --ssesesceseces aieeee essen ee 77 RGR niiONalh COMPRESSES: -2 25. So cn caceene ak umcmiod ss xeicsGrucs sets Maeno ae 12, 24 International exchanges: A PPro priatiONs ANd EsMMALES 255 los sacecscss.. ass nec ceewosee swabs 5, 53, 90, 103 DepusitOniese = - 1c te. eden we on. esos ee x an eae san cee eee ono 57 794 INDEX. International exchanges—Continued. Page. Printing allotments cseeaeee oe eet eee ese ee eae ieee eee ane 20, 102 Publicationsstiramsmitted tees ss see rer ee ere eee ere naa oe eee Reerne 32, 55 Re porto the Secre baryon ance Cte ace aicyeerecn ager ee oleae ae arena oe oe 30 Report.of Assistant Secretary 22. : 2. = 22's ees oct eed oe ens wee eee 53 Rules;soverninovexchanpess eccca sete saat 47. oases aaa a ae eee 60 lisopods(htichardson))*2esss-/s ser ete ee ie rarest eres ee ees 80 J. ACK OT EA AVRIL cots arson oe cus aman eevee ee sre ay cs ake ta ep UIST Ah ae ee ae 25 JAMestO we E XPOSTLLOM.) (222 ene cjotia rie eee eens lee ae ea ee 28, 41, 42 SAS DEON pL ORGISA T= ch = eaciereat te accyere alee, he Spay Se ee orev a eee eR 25, 26 Joly. sohni (Uranium: andieeolory)icaccreas-- cee came coe oes oo ee eae 305 omesss Wallliarane ss ema se et Aer ee cins ae Se 5 Sis Dieee sSNA cere erie See eee 46 Viorel ana spl) aay aS terres ie se orc ates Opa a eee eter ny gat ey ee eee 81 Jourdain, Pierre-Roger (Aviation in’ France in 1908)._-22-----.---2---------- 145 Ke Kapteyn, J. C. (Recent researches in the structure of the universe)............ 301 TS hevamalselovelys ces Sate eek en Della AC hee pane ape 162, 366, 745 Kelvans iierands works oi (i homipson) seers ss see ee eee ee oe ene ee ea Kendall Wallltamm Comverse eacsce ssn cse ea ee a eiacie ee ee ee ein ee eee 81 Key. Brancis SCOtt sca. .)aaeni see: ee cctac a ceoe han oo een nee eel eee 27,39 Reim pi@harlessAys <2 vera chs sett, ohare hs craia Sa atatrs cx aonye ger cya ree Yea 61 [Koval ovwBired eri @ke: eseevis aes eee aarti ore ee er nh ee Ie 2 81 1 (6) (00 Lk Coes Ue ree eee rsa are aN nny Se One yA ee ea RR Rey ras ho ehe gM Mi vee 16 iReraurnv ere Ate see ios 18 2 ee a eee ashes eee eres to SE RST ais Seay ape ie Supe 8 72 Ir oe bern Ars lbis 5: sn hues oey ee le neha ean oye he Lie aye ream a eres Oe pee poe 46 Ibe Baeblesche. Brancise: 22 c's saee outta soe oe See eee eee 46 Langley, S. P. (Third Secretary Smithsonian Institution)................... 8, 18, 33, 72, 82, 84, 136, 138, 142, 145, 169, 321 Tanna aninG Rie aos. c nce Jeena eee ee obs Se Se ees ec eee See ee eae ee 25 atham sEUbert ee Seo Gey et ont eee tales oe aap tard aes ee lee rere eae oe 158 AU ROUTE Ay EXE) etl 0G) Ko BERR ee RMA aa Bee UE Ce ae Ee UE Ae oS 80 Lebaudy ‘Brothers ss52%.2- 25 22 24 oh fe ve site 32 = Bde Sas oe ie sie ee eee 118, 128 eChUTes ee ace BSS sek a oc ado oa ok od Be ota SSE CRIA oe et eee eee ose eeeee 26 ken denteld AR Voli vetoes. ee Se ie Ba eee eee eee eee 14 Wbewiss A.B Oo gevaess dosGele cei ey Be Le 3 ate ee aes Secor eye ee aetna 46 Tews ed): Ms eeeide ose Cee eee eee eee ees cee a es ee ay eee eee ee 15 Ibibrany: of Conpress. 244. 2222 Sie oaks eee eee ae ee ope ere 21, 73, 102 Library of Smithsonian Institution: UAC COSBI ONS 2 cihetee = Sete Nee ew ane neces iat eth Pav ae a a Year ve 21,73 APE TOOMD LSS Lhe bs 2ielas aie net cievostsva sete croe araveeinjsine tees eeis Gee ee eee 74 Deposit inbibrary.ot\Coneress:— eres ee ae eee ee eee eee 21, 73, 102 Employees’ llapary...02-222 co o02e be deiget t ces te Ree eee eee 74 Marsh enoravings ye s.2.24 i CSS eee en enact See oe eee 22, 14 Reportiol: Secretary. 32 328 sose2 ee ea ce = te ee eera eee 21 Report of Assistant Secretary ...2..222.2t5=-ssc2 ace eetes eis oe ee eee 73 Sectionalulibrariéss.2a5c0 osc ne steels ane eee eee eee eee eee 42,73, 75 Lihenthal (@tto 25 s2fetes ss oe Sei ketal nie oe an 145 Linné.as'a. geologist. (Nathorst)- .)2. 2.22.05... cee eee oS eee 711 INDEX. 795 Page edge SenatomtHenry Cabom(Rerent)esas.5-2. ose oon ee eee eee ee Ix, 92 hod sen Olivers: may taee caer eee ie ene et es re A 162, 164, 166, 174 ondon)Genlosicalssocienys asec tec see ces oe hace eee Me ee 25 owmdes:» Nira: anmese sti. See ees ee oe ee Pm ees Se oe a on Lull, Richard 8. (The evolution of the elephant).........................---- 641 Mommies Ghiatrles abr nscns cocee ace ss ee nag Mews 2 ost CS he ee 46 arempsnic wera Bh et Gill yee see eet keh Se RES Se A ee eg a 80 Lyons, H. G. (Some geographical aspects of the Nile)..................-..-... 481 M. MeGindyaiGeorre Grant. sont. ute ee OAs Ge one oo eile ean we aed RN Pa es 25 Puli te] Gri ideale (03125 6) 6B 9 ae eRe ea ee cet erie pC ee PO Pace aha ene 46 MacDougal, Daniel Trembly (Heredity, and the origin of species) eo ee 505 Machat, J. (The antarctic question; voyages to the South Pole since 1898).... 451 E75 tb Tee A te a ee De Se ee Cae a ee 10 Mrilamaim: Greeee (Ross). tose eee ass sae as ene le Roe Rie ae eee kee 697 Mermmals trom Kan oul (iy OR)es. sree Sarg oe abc oak ees cere O85 80 IZM 7 0) eh Pet) ater ee Ce eT ae Re eg sta 3 rte SR ea 8 Mann, Representative James R. (Regent).......................--.- 1x, 2, 92,97, 101 MECReEOTE VW ALIIAITI ers doe Sac chieee ees tenons ee Cee 165, 170, 174, 191, 193 Marine Mornpinaln Service. .fa25 2322 oso eae aes he toa ee eee 40 MAING CORO e MP OMICS. go Naee aso A Seok ace eee ON Sat pene tee 22, 74 WER SORE NO DIAN eo toes SARE ee a RR So eS Tne) bi Neato ne RA ee Wr al x, 41, 46, 75 Mathematical Tables (Becker'and Van Orstrand)::....2i 2222. ..2-4 5 2522s 82 Mathematicians, Fourth International Congress.....................-2-2------ 25 Matter and Ether (Thomson)................... EO Se A es 233 Matter, Properties of (Nichols)... .... i atte amar Duis ahaha ties tee eT ae 11 UP cu EN LET See fers oe Re en ae lok Se a Se eg Bm a eee a ee 145 INIEECOTIN IVs EU ot Pe Socket. ae eh ets Gu 2s huh, CUS eine Been et ee 80 Mearna MayesBi Av, Ws Ss ARMY 2es. <0 22h oe So Aelia ores et OU ma Mectings of Board. Of Revents: .22 2235265285 232 oesee 3. 2 oso. eS BO LOO Mercator Prajecuone so. ¢ sms. 8-5 te. see aac noun ae aie 5 en eae eee 18 Merrill, George P.. Serato aS ae Sle etajeve spo a = Ue To TS Eat eee O NATO OI Mesa iene National Dorie. Seat Iota ot Sey Vt yee Se bw Gh AR po eee i 23, 48, 101 Metcalf, Victor H. (Secretary of the Navy).. ee ree memes en i s.e i Metetor Crater, Meteorites, etc. (Merrill-Tassin).. Pe es eee Pe ates 9, 41, 80, 81 Mexico, Indians of (Hrdlicka).. EEE SS eee ec ott al pee ee 51 Mexico. Cnetacereof (Safford)! o252 s+. ota 5 i0' 52 fais. o's oe aie seins se ae aeleeeeees 451 Postmaster-General (Member of Establishment)........-....---- Ete a Stes Oa 1g IL ipolisenis toleoraphones a5 chia. dee janes can 2s. seek ae sesame ane ae ee 207 President of the United States—Theodore Roosevelt—( Presiding officer of the AMEE TERTOUD) elem ots eee On Ne re aie atten ay Se etree ee See xen ley [ELIT AG 1G hte re ee nS =e Seen oP ene eaten Meee ain oe ey ac ce 20, 102 Printing and publication (advisory committee). .......--...-..-=---+------- 21, 85 Prizes for essays: (OTE E MBNETIOS Sat. seer toe en sess N old ye asec eter oe ees See 25 Onvitibenculagis: :.52)b.geer seg no eo a ke oe Cee cero ee ee 12,25 Protablativa hamuly (Mitchells 22) pce. cee aoe = re ao ne eer eee 81 CEO DOGS CL AMN eee serclns nts Sr aeie le Rarer URL ee eh eae eee 81 Publications: PNETOMAUICLCS Ae So Cie ended a hee) tee eres Sis ae iar ana get ie 8 ATI GAL FEPOP ds 25 so Monee ss eS 1, 17, 19, 27, 36, 42, 44, 53, 62, 68, 73, 77, 79, 84, 87, 98 Contributions to Knowledge..-....-.-- Pe EE ee tee 5 eee M75 09 Manco lanecous Collections =< 220 tc. .entee ce nis -2 os ee sso are ee ee 17, 80 (OUST ered ih ts 21s Pye leg tte 02 eae ee aye epee EIA Pies Aeeenpe ag Ne Sie ee 18, 80 ‘Smiithsonianktalp lessee cece ccs aie rere e se eiera er reinya nial Oe are eee ee 18, 82 Special yon blicapons 225 oot. S ate ae2 Weasels ee oo ae ee 19, 83 Puchstein, O., and Hugo Winckler (Excavations at Boghaz-Keui in the sum- riiterat0) il Kea se eNO COE eSe A GAB iane eon aes Se ae ers Teor eden A, = 677 Q. GIInREGriy ISSO owes ois = se eisai DSU So PERE e ec rche sot BRS cee = 18, 80 Quito Hx positions). J)... 0). 2.2 -.42-s=2-2255 22 se< eecess se ease ee 102 Cooperation with scientific societies, etc.............----------------- 19, 25, 27 @orrespond enCGsa ses aeons onioe oosersls bas lesa sors Someta 2 roe eran ete 24 intablishiment-— sae fie see ses eee eee he ee cee een reel RpaplOrahlORs en ecm Ss eee A532 ees es occa aoe tea oo eae eee 7, 39, 47 PE PORIMNONS COUPTCHIES, COC. 55-5. 6-32 sess ec ae ae aa ee 12, 24, 41, 42, 45, 96 Guitsvandyloanss eetcer ea tee Cons ooc ees fas dosage = cece eeees 27, 28, 74, 94, 95 Goverument branches under. 525.0302 sec 92 En ae Sate se cole ee eee 2 (Gran tS Sees ce ee ese Pe nei nete eco ae t Gee Seine ale a ree eee LOST a GYOUNGH OLS se eeoc scone eae = ae oe le os see Sees = eo re sea Sensi eet 102 i aveorsrrevernats Weey.] see fone eens See 11 Speciesandiheredity (MacDougall). ce say epee = Salsas se ech oe teiareteioraee 505 Spec ksaw anaes pe ene Seas a ena ts REMI Laan ae Yar gavin ie in ae BUM os VOR PA ae ere te 46 Sprague, JosephyuWhite (bequest) aaa secre. soins ae gene ee ee mercer ace 99 Squier, Maj. George O., U. 8. Army (Present status of military aeronautics)... 117 Scantishes) (Hisher) Sosy eee DOM ris Siar sede a cel Au CBee ede eee eee tere ac 81 “otamopangied Banner) 6 ssccelk bagasse ected eee che dee el eee ee meee Zi; 39 StatewDepanrtimentiObs) oAcasae ewes ot Se eae Clalit ie Bute ome eee ueee onaaeet 19 State, Secretary of (Member of Establishment)...................-.-..-.-.-- pay Stejneger: wbeonhard 55. 222 oss Sota oo ede else SER A es meee Bg ZAll, yl Sicrnbere*George:Mareec sedans eee ate aa Se tet ee ee enh eee reo 13 Stevenson M rate. = Shs cies ooh, Pea esteem adore het ec cl ater a er eee tea x, 45 Stimpson.) Walliams 1 eats oe ho tes alas 3s 2 sae sci ws erry ore ieee 82 Straus, Oscar S. (Secretary of Commerce and Labor)...............--.------- 10.6)! SMmuS po tanCA Ot eee aire eels oveicys sta ia eek Meacts e mrsle Na oy ees A see eee eae 321 SUUrO Ne Od OTesr somes, sete eae oS ap a ee epee, -Andrew 1) (hegent))<2)<..2 ani nctle ance = ase tives 2 alee eet ooeees Ix, 26, 82, 92 VTLS) CON Bee Ae ant een ELS OOO nS REA tS ear A Se 75 Aine. “CD tae Paes, SM hee ae ae ae Sap ee Se PR ts See A 3 Piiiteteh: (Mendall) ss 2s2 ho ee eco a eames es Sault simian serine atete 81 Wiechert, E. (Our present knowledge of the earth) ....................-..... 431 VEU e Cice, Wis ae eres nen ere wat ge te ce Rens ieh hn SN Sc es ted Se pc 50 SUSU ed 2 Ai Ds AOne i ee Ae Une Oe ME i oMine an eae Reo Eom asc 80 VSI ne rsp [eat BF 00).1{6 De Se ee ene oN ene te aeere see ac acura oc 16 Reiley ees ys a ae tls cree Qeae is ere ala ia aye ialoidines ep2)=t aaa ate Sean ea eo 10 MIL Ste ak Gn O Reta te ARCOM Se * Se SAE AOD aN AC Ma OnE econ asian SeececceeS 46. Nyalson® games (Secretary of: Acriculttre))s,.22.2. 22.022. o8ecee = ean see aeee ph ea! Winckler, Hugo and O. Puchstein (Excavations at Boghaz-Keui in the summer OH CM socacoted secccsadds onersposcasunccneuocoes tor socapossocccoesbaec 677 Winclessnclepnony CE CSseRGEN) a. iene alate clei oe ae ee eee 161 VUES eri G1 Ee si) Nk A Be a a ie Pe te LSPS Chan en eee ge rcs kr 46 Witt, O. N. (Development of technological chemistry during the last forty years). 255 Narr ea Crerne (Oi rh7o at DRM Ofayicte 9: a 06h Ane Re PIR ree noice Seba es es = 38, 41 MUO MIN On HOMOr ec nee che fea eicia me mieia me ioave mie ete ee = eee eee 96 feared 1 Hl 83 <0) 12 9s ee eee Ine eee cate ne ce 133, 137, 140, 151, 154 Ni. SAI GMO yesh epee EAS See BORAGE OARS Een ao uer OOS Sme ras aac c™ 40 : Z. Beppelin, Count 2... so. sacs cesses 0-2 enn in = ww ie = a ae we ee 130, 182 Ziegler Arctic Expedition.........--.------------2--- 2-2-2 eee eee e ee eee eee 42 Zoological Congress... .....------------- 22 eee seen ee eee ee eee eee eee ee eees 24 Zoological Park, National... .....---------------++-e-2+e+----- 2, 5, 21, 24, 32, 62, 90 O rir it i ————— — co | WY Ni 3 9088 01421 6923 | | | | |