GAM I) W¥¥ WEIS WO GGe Vy WAVIGhAL Sy ee thee wil sta : Argentinas: Pe eeunee “WS Pcie wvayVO ioe orc cae at = ree eee”, ver WV YU UaY v Ww vulyets wy W whi eine “\ uS Saag we onan NY) vey WW We iWyvy yyy a i Weed Ww SE CES IIIT vriry rarity : f wi Meee Ny Way vo no en WW veani aaa ene ive wit ‘ ww , cer NV Fy eis WW See gee Ne YW cx eee Law "NAN UN 9 he UMA Svea yy iy EO < UE 2 Se EE § CCC reareas < Wi) vi CN ay NY ey aes Wer cay : mis ain. i v v v ' / ¥ : ye Wits ’ v Wy | i VY ud} es Vy wiv. | eee “i yY’vuy | is vs ie i iaaeesa in NMA WYNYYS UN Uy y Wii Yyvosuns Sy MMW Tne suo OO Rh aad oc oe eee... — Department of the interior. ‘ \ é é Books are issued to and returned by employés, between the hours of 11 a. m. and 2 p. m. on all days except Sundays. o The Library is open to employés, for reference, from 9 a. m. till ails 4 p.m. ’ 8 8 8 ee, LIBRARY RULES. 1. The employés of the Department of the Interior only are authorized to borrow books from the Library. 4] - 2. Before being allowed to draw books employés will be required to file with the Librarian a certificate of identity from the Chief Clerk of the Department, or of the Bureau or Office in which employed. 3. No book will be taken from the Library until its title and the name of the borrower shall have been registered by the Librarian. 4. Of works of single volumes only one at a time may be borrowed ; of works of two or more volumes two may be taken. 5. The period of a loan of books is for two weeks, and borrowers are strictly prohibited from lending books thus drawn to other persons, whether of the Department or not. 6. Borrowers wishing to retain books for a longer period than two weeks, ' may at the close of the second week renew the loan for an additional twow 7 weeks. ‘ 7. The loan of a book will be renewed but once. 8. Books classed as ‘‘ Works of Reference” or marked in the Catalogue with an (*), cannot be taken from the Library. 9. When a book has been injured while in the possession of a borrower, it must be replaced by a perfect copy. ‘ 10. Application for and return of books must be made in person, except in cases of sickness or absence from the city. 11. Books retrned will not be reissued until they have been examined and replaced upon the shelves. 4 12. When a book has been retained by a borrower beyond two weeks without renewal, its price will be certified to the Disbursing Officer of the Department, and deducted from the salary of the person withholding it. 13. Writing on the leaves or covers of books, and the folding or turning down of their leaves are strictly prohibited ; violation of this rule will debar employés from further privileges of the Library. : 14. In selecting books from the shelves, care must be used in handling them, replacing those not drawn on the shelves from which they were taken; the num- ber of the shelf may be ascertained from the label above. - 15. Employés, on quitting the service of the Department, must return all rie books in their possession belonging to the Library. Final payment of thei salaries will be withheld by the Disbursiug Officer until he is satisfied that all books charged against them at the Library have been returned. 16. New books can be drawn for one week only, and not renewed. 17. Current periodicals can be drawn for three days onky, and not renewed. : cry 18. For infringements of any of the above rules the Librarian is authorized to suspend or refuse the issue of books to the culpable persons. y order of the Secretary : GEO. A. HOWARD, 14520 b—1 m Chief Clerk. — BA Ps ‘ ’ ’ id o ¢ ANY yh oy - ‘ i hie Peat dia te ha oe Te ee ae ay oda eh Mf ic \ nN q % ! , ‘ a \ » 7 as Ye eh ia SMITHSONIAN MISCELLANEOUS COLLECTIONS, 23 VOL. XX XIII. “EVERY MAN 18 A VALUABLE MENEER OF SOCIETY WHO BY HIS OBSERVATIONS, RESEAKCHES, AND EXPERIMENTS PROCURES KNOWLEDGE FOR MEN.”’—SMITHGON. WASHINGTON: PUBLISHED BY THE SMITHSONIAN INSTITUTION. 1888. ADVERTISEMENT. The present series, entitled “Smithsonian Miscellaneous Collec- tions,” is intended to embrace all the publications issued directly by the Smithsonian Institution in octavo form; those in quarto constituting the “Smithsonian Contributions to Knowledge.” The quarto series includes memoirs, embracing the records of extended original investigations and researches, resulting in what are be- lieved to be new truths, and constituting positive additions to the sum of human knowledge. The octavo series is designed to contain reports on the present state of our knowledge of particular branches: of science ; instructions for collecting and digesting facts and mate- rials for research; lists and synopses of species of the organic and inorganic world ; museum catalogues; reports of explorations; aids to bibliographical investigations, ete., generally prepared at the ex- press request of the Institution, and at its expense. The assignment of a work to one or the other of the two series will sometimes depend upon whether the required illustrations can be presented more conveniently in the quarto or the octavo form. In the Smithsonian Contributions to Knowledge, as well as in the present series, each article is separately paged and indexed, and the actual date of its publication is that given on its special title page, and not that of the volunre in which it is placed. In many cases works have been published and largely distributed, years before their combination into volumes. S. P. LANGLEY, Secretary S. I, vid AALS 7 “8 Fal : ba! . ’ f i aga . ; ‘ 6 ‘ m we K's ‘ i “ +4 : us ' Fricc "i ra ‘ { ” j ; 7 Asay le f e4 y f 4 -. . : ' : ‘ A ' Wail wh) Yay é + : dit ‘ ale | ia id ALi r ! ; . ; ' wi ty thy Ps ‘ ‘ pe ' j b ean iy ny ’ \ ) r “ ' 7 1: vee \ a 1 ) + yp +31 Glie ‘ e ’ 4 J Rae re * y ! 4 4 Aew ‘ { he Pau eo / 4 ‘ . va = . ‘ / + vA Vie Ey * : A! ’ e : t - ‘ i J - wien “ j : we Nas , mAs iy TABLE OF CONTENTS. ArticLte I. (543.) BUuLiLEetiIn oF THE PHILOSOPHICAL SOCIETY or Wasuinctron. Vol. VI. For the year 1883. Pp. 220. ARTICLE II. (592.) BULLETIN OF THE PHILOSOPHICAL SOCIETY oF Wasuineton. Vol. VII. For the year 1884. Pp. 194. ARTICLE II]. (636.) BuLLETIN OF THE PHILOSOPHICAL SOCIETY oF WasuinGcron. Vol. VIII. For the year 1885. Pp. 115. = ArtTicLE ITV. (661.) BuLLEeriIn oF THE PHILOSOPHICAL SOCIETY or WasHinetTon. Vol. IX. For the year 1886, Pp. 115. And Vol. X. For the year 1887. Pp. 2638. NOTE. With this volume—(containing the last five volumes of the “ Bul- letins of the Philosophical Society of Washington”)—is terminated the reissue of these proceedings in the series of MiscELLANEOUS CoLLEctions. It may be stated that volumes 1, 2, and 3 of these “ Bulletins” formed Vol. XX of the Miscellaneous Collections. Volumes 4 and 5 were included in Vol. X XV of the Miscellaneous Collections. And, lastly, volumes 6, 7, 8, 9, and 10—together with the Memorial Proceedings in honor of Prof. Baird, and a full Index of the whole ten volumes—constitute the present Vol. XXXII of the Miscellaneous Collections. (5) BULLETIN OF THE PHILOSOPHICAL SOCIETY or WASHINGTON. VOLE Containing the Minutes of the Society for the year 1883, and the Minutes of the Mathematical Section from its organiza- tion, March 2gth, to the close of the year. PUBLISHED BY THE CO-OPERATION OF THE SMITHSONIAN INSTITUTION. WASHINGTON: 1884. CONTENTS. Page a ISIE ep ae a Sa a i ed reine VII Standing Rules of the Society____-__.__----- Ca A BE a eink Ce a aL IX prams Euules. of, the General, Committee. 25 -- | 2 Le XII ulecaur tne. aplication ef the. Bulletin. 22 22) J XIII Wihecersiclectedu Mecem pers Tooe cua a a ORT G@iucersrelcctedsWecembely OO ste saaa ae eae ee ee oe ee XV msHomeviembers,corrected,to) December i, 1863-52 2 ee EVI AnnngNenOru Ot the: Dreasuren: 2 = = Sos ee ee RITE mnaual Addressiof the President, J. W..Powell_.=.-<-—...-...c...=. | EXV Hollennreiathe GeneraleVMeetine 2 2. oe eA ee ee I Experiments in binary arithmetic, H. Farquhar___.-_-_--------... 3 Refraction in a triaxial ellipsoid, ( 77¢/e only,) S. M. Burnett-_-__~ 4 Monochromatic aberration in aphakia, ( 7zt/e only,) W. Harkness-_- 5 Whe matare of matter,.( Z72z/e ovtty,) H. H. Bates\s-W-- ~ 2: 5 Prevention of malarial diseases, A. F. A. King_-__-___--_.-_-.- 5 Response of climate to variations of solar radiation, G. K. Gilbert. 10 Thermal belts of North Carolina, J. W. Chickering-_____-.-_-____ II Geology of the Hawaiian Islands, C. E. Dutton _______._---_-__- 13 Substance, matter, motion, and force, ( Zz¢/e only,) M. H. Doolittle. 14 Formulas for the computation of Easter, E. B. Elliott___-__..____- 15 Florida expedition for observing transit of Venus, J. R. Eastman. 21 Determining the temperature of the air, C. Abbe_-__.______--___- 24 Determination of specific gravity of solids, C. E. Munroe____-_____ 26 ieelomyotbintteras., W., CO. Merino 2.) 8a ec 28 Topographical indications of a fault, H. F. Walling______-_--__. 30 Ore deposition by replacement, S. F.|Emmons___.---.-......--. 32 Glagavon tm. Alaska. WoT. Dall 222 oe a ea Se a eis 3 The Eucalyptus on the Roman Campagna, ( Zi¢/e only,) F.B. Hough 36 Elyemometrc observations, Hi. A. Hazen-2-. 0+ s-.-. 222-8. 36 Dreams in their relation with psychology, E. Farquhar__------.-. 37 Recent experiments on serpent venom, (7Z7¢/e only,) R. Fletcher___ 38 Further experiments in binary arithmetic, H. Farquhar_-----_-_-- 38 Medallienmecicalphistory.6 We duce =.= 8 —— sae en ene oec aay 39 III Iv CONTENTS. Bulletin of the General Meeting—Continued. Note on the rings of Saturn, W. B. Taylor_-_....-—_ --.-.----== Focal lines in astigmatism, ( 72¢/e only,) S. M. Burnett------ ----— Thermometer exposure, Hi a. Flazen "22-2 eee Ichthyological results of the Albatross, ( 7z¢/e only,) T. N. Gill---- Fallacies: concerning, the deaf, AUG. Bell 2222 2) 2S Sane e eee ae Seismographic record from Japan, ( Zz¢/e only,) E. Smith_--------- The volcanic problem stated, C. E. Dutton... --2== ee ee ee Drainage system and loess of eastern Iowa, W J McGee --------- Cambrian system in the United States and Canada, C. D. Walcott - Distribution of surplus money of the United States, J. J. Knox.-__- An initial meridian and universal time, R. D. Cutts___.-_-._----__ Bulletin of the. Mathematical Sectione=_. 1222222 Sa Rules ofs the Secon as. 2 ae eee ee ee ee ee Inaugural Address of the Chairman, A. Hall_-_----__-_--_-_____ A quasi general differentiation, ( 77¢/e only,) A. S. Christie____-__- Alignment curves on any surface, C. H. Kummell-__. -----.___-_- Determination of the mass of a planet, A. Hall ---______________ Infinite and infinitesimal quantities, M. H. Doolittle ___-__.-_____ Graphic tables for computing heights, ( 72¢/e only,) G. K. Gilbert__ Computation of lunar perturbations, G. W. Hill_---.---------___ Units of force and energy, ( Z7#e only,) E. B. Elliott ___-__-.__ pe Theory of errors tested by target shooting, C. H. Kummell___-___ A special case in maxima and minima, B. Alvord ._____--___.---- A financial problem, E.B. Elhotty 22 (225522 ee A form of least-square computation, H. Farquhar -_-________-___- Note on problem discussed by Mr. Alvord, H. Farquhar -__-___-_. The rejection of doubtful observations, M. H. Doolittle--_-__ -__- Special treatment of observation-equations, R. S. Woodward_____. Contact of jplanetcurves,"A.,S; (Christie ae eee abs Committees on papers.- 4 JUS oi a oo ee Corrigenda to Vol. ‘V..2-- ee a ee 6:1; [a re ee Ui tie sy pew ay CUES BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. CONSTITUTION, RULES, LIST OF OFFICERS AND MEMBERS, TREASURER’S REPORT. CONSTITUTION OF THE PHILOSOPHICAL SOGIETY OF WASHINGTON. ArtTIcLE I. The name of this Society shall be Tor PHILosoput- CAL Society oF WASHINGTON. ArticuE II. The officers of the Society shall be a President, four Vice-Presidents, a Treasurer, and two Secretaries. Artic.E III. There shall be a General Committee, consisting of the officers of the Society and nine other members. ArticLe IV. The officers of the Society and the other members of the General Committee shall be elected annually by ballot ; they shall hold office until their successors are elected, and shall have power to fill vacancies. ArrtIcLE V. It shall be the duty of the General Committee to make rules for the government of the Society, and to transact all its business. ArtTIcLE VI. This constitution shall not be amended except by a three-fourths vote of those present at an annual meeting for the election of officers, and after notice of the proposed change shall have been given in writing at a stated meeting of the Society at least four weeks previously. Vii ats, °o. = ; ‘ Rh “e u) ely 7 ( f PENS et a . yee re: Me ea ee Peg. sick ck a nce ey Y f é ae Uns ; ey as i m vb f Vis 4 oy 12>, a ma k » { eae T we F ; , t ‘ «4 hey on. s A ' y : "i ; \ 1 ad ? STANDING RULES FOR THE GOVERNMENT OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. 1. The Stated Meetings of the Society shall be held at 8 .0’clock P. M. on every alternate Saturday; the place of meeting to be designated by the General Committee. 2. Notice of the time and plaee of meeting shall be sent to each member by one of the Secretaries. When necessary, Special Meetings may be called by the President. 3. The Annual Meeting for the election of officers shall be the last stated meeting in the month of December. The order of proceedings (which shall be announced by the Chair) shall be as follows: First, the reading of the minutes of the last Annual Meeting. Second, the presentation of the annual reports of the Secretaries, including the announcement of the names of members elected since the last annual meeting. Third, the presentation of the annual report of the Treasurer. Fourth, the announcement of the names of members who, having complied with Section 13 of the Standing Rules, are entitled to vote on the election of officers. Fifth, the election of President. Sixth, the election of four Vice-Presidents. Seventh, the election of Treasurer. Eighth, the election of two Secretaries. Ninth, the election of nine members of the General Committee. Tenth, the consideration of Amendments to the Constitution of the Society, if any such shall have been proposed in accordance with Article VI of the Constitution. Eleventh, the reading of the rough minutes of the meeting. im x PHILOSOPHICAL SOCIETY OF WASHINGTON. 4, Elections of officers are to be held as follows: In each case nominations shall be made by means of an informal ballot, the result of which shall be announced by the Secretary; after which the first formal ballot shall be taken. In the ballot for Vice-Presidents, Secretaries, and Members of the General Committee, each voter shall write on one ballot as many names as there are officers to be elected, viz., four on the first ballot for Vice-Presidents, two on the first for Secretaries, and nine on the first for Members of the General Committee; and on each subse- quent ballot as many names as there are persons yet to be elected ; and those persons who receive a majority of the votes cast shall be declared elected. If in any case the informal ballot result in giving a majority for any one, it may be declared formal by a majority vote. 5. The Stated Meetings, with the exception of the annual meet- ing, shall be devoted to the consideration and discussion of scientific subjects. The Stated Meeting next preceding the Annual Meeting shall be set apart for the delivery of the President’s Annual Address. 6. Sections representing special branches of science may be formed by the General Committee upon the written recommenda- tion of twenty members of the Society.* 7. Persons interested in science, who are not residents of the Dis- trict of Columbia, may be present at any meeting of the Society, — except the annual meeting, upon invitation of a member. 8. Similar invitations to residents of the Distriet of Columbia, not members of the Society, must be submitted through one of the Secretaries to the General Committee for approval. 9. Invitations to attend during three months the meetings of the Society and participate in the discussion of papers, may, by a vote of nine members of the General Committee, be issued to persons nominated by two members. 10. Communications intended for publication under the auspices * Under this rule the Mathematical Section was organized March 29, 1883. Its rules and proceedings follow the Bulletin of the General Meeting. STANDING RULES. XI of the Society shall be submitted in writing to the General Com- mittee for approval. 11.* Any paper read before a Section may be repeated, either entire or by abstract, before a general meeting of the Society, if such repetition is recommended by the General Committee of the Society. 12. New members may be proposed in writing by three members of the Society for election by the General Committee; but no per- son shall be admitted to the privileges of membership unless he signifies his acceptance thereof in writing within two months after notification of his election. 13. Each member shall pay annually to the Treasurer the sum of five dollars, and no member whose dues are unpaid shall vote at the annual meeting for the election of officers, or be entitled to a copy of the Bulletin. In the absence of the Treasurer, the Secretary is authorized to receive the dues of members. The names of those two years in arrears shall be dropped from the list of members. Notice of resignation of membership shall be given in writing to the General Committee through the President or one of the Secre- taries. 14. The fiscal year shall terminate with the Annual Meeting. 15. {Members who are absent from the District of Columbia for more than twelve months may be excused from payment of the annual assessments. They can, however, resume their membership by giving notice to the President of their wish to do so. 16. Any member not in arrears may, by the payment of one hundred dollars at any one time, become a life member, and be relieved from all further annual dues and other assessments. All moneys received in payment of life membership shall be invested as portions of a permanent fund, which shall be directed solely to the furtherance of such special scientific work as may be ordered by the General Committee. * Adopted, May 19, 1883. ¢ Amended, Nov. 10, 1883. STANDING RULES OF THE GENERAL COMMITTEE OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. 1. The President, Vice-Presidents, and Secretaries of the Society shall hold like offices in the General Committee. 2. The President shall have power to call special meetings of the Committee, and to appoint Sub-Committees. 3. The Sub-Committees shall prepare business for the General Committee, and perform such other duties as may be entrusted to them. 4, There shall be two Standing Sub-Committees; one on Com- munications for the Stated Meetings of the Society, and another on Publications. 5. The General Committee shall meet at half-past seven o’clock on the evening of each Stated Meeting, and by adjournment at other times. 6. For all purposes except for the amendment of the Standing Rules of the Committee or of the Society, and the election of mem- bers, six members of the Committee shall constitute a quorum. 7. The names of proposed new members recommended in con- formity with Section 11 of the Standing Rules of the Society, may be presented at any meeting of the General Committee, but shall lie over for at least four weeks before final action, and the concur- rence of twelve members of the Committee shall be necessary to election. The Secretary of the General Committee shall keep a chronologi- cal register of the elections and acceptances of members. 8. These Standing Rules, and those for the government of the Society, shall be modified only with the consent of a majority of the members of the General Committee. xii ey eS FOR THE PUBLICATION OF THE. BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. 1. The President’s annual address shall be published in full. 2. The annual reports of the Secretaries and of the Treasurer shall be published in full. 3. When directed by the General Committee, any communication may be published in full. 4. Abstracts of papers and remarks on the same will be. pub- lished, when presented to the Secretary by the author in writing within two weeks of the evening of their delivery, and approved by the Committee on Publications. Brief abstracts prepared by one of the Secretaries and approved by the Committee on Publications may also be published. 5.* If the author of any paper read before a Section of the Society desires its publication, either in full or by abstract, it shall be referred to a committee to be appointed as the Section may determine. The report of this committee shall be forwarded to the Publica- tion Committee by the Secretary of the Section, together with any action of the section taken thereon. 6. Communications which have been published elsewhere, so as to be generally accessible, will appear in the Bulletin by title only, but with a reference to the place of publication, if made known in season to the Committee on Publications. * Adopted May 19, 1883. 2a ili OFFICERS OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON, ELECTED DECEMBER 16, 1882. Presedentzs o2es te J. W. POWELL. Vice-Presidents..____-- J. C. WELLING, J. E. HILGARD, C. H. CRANE, J. S. BILLINGS. Treasurer _...~- eons LEVELAND ABBE. Secvetartes. Pane ae G. K. GILBERT, HENRY FARQUHAR. MEMBERS AT LARGE OF THE GENERAL COMMITTEE, W. be DATE, C. E. Dutton, J. R. EASTMAN, EB. BE Luror R. FLETCHER, Wm. HARKNESS, D. L. HunTINGTON, GARRICK MALLERY,* C. A. SCHOTT. STANDING COMMITTEES. On Communications + J. S. BILLINGs, Chairman, G. K. GILBERT, HENRY FARQUHAR. On Publications : G. K. GILBERT, Chairman, HENRY FARQUHAR, | CLEVELAND ABBE, S. F. Bairp.+ * Mr. Mallery was elected Vice-President October 13 to fill the vacancy occasioned by the death of Mr. Crane. Mr. C. V. Riley was at the same time added to the General Committee to fill its number. + As Secretary of the Smithsonian Institution. ’ X1V OFPERICHRS OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON ELECTED DECEMBER 22, 1883. GhEStO Chia ae ha Os. WELLING: Vice- Presidents ___-_- J. S. BILLINGs. GARRICK MALLERY. J. E. Hivcarp. ASAPH HALL. TT EQLSUR ETA Ae ae wes, —.CLEVELAND ABBE. MSEC CLOT TES ae we HENRY FARQUHAR. G. K. GILBERT. MEMBERS AT LARGE OF THE GENERAL COMMITTEE. H. H. BATEs. E.. B. ELLIortT. W. H. DALL. ROBERT FLETCHER. C. E. DuTTon. WILLIAM HARKNESS. J. R. EAstTMan, J. J. Knox. C..V. RILEy. STANDING COMMITTEES. On Communications J. S. BILLInGs, Chairman. HENRY FARQUHAR. G. K. GILBERT. On Publications : G. K. GILBERT, Chairman. CLEVELAND ABBE. HENRY FARQUHAR. S. F. Barrp.* * As Secretary of the Smithsonian Institution. xV LIST OF MEMBERS OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. Corrected to December 31, 1883. The names of founders are printed in Sma CapPiraLs. (d) indicates deceased. (a) indicates absent from the District of Columbia and excused from payment of dues until announcing his return. (r) indicates resigned. NAME. P. O. ADDRESS AND RESIDENCE. Abbe, Cleveland.. ...| Army Signal Office. 2017 1St. N. W... Abert, Sylvanus Thayer.. sbidoa cugeteduens Engineer’s Office, War Department. | 1875, Jan. 30 1724 Penn. Ave. N. W. Adams, ITenry.........0-000 Hincsenstarentent TOOT ES. ee cecsscesneveus eadesen versed heeesceentd 1881, Feb. 5 Aldis, Asa Owen.......... Wecsaeneenntomegenas THUG ET GE IN, Wiesssctacccu eet 1873, Mar. 1 PATTET UAMIGSS.: peedareasessesecenseseessve ...| Army Signal Office. 1707 G St. N. W..} 1882, Feb. 25 Alvord, Benjamin ...........::00ceeee SOL LZO TG tieg Ne) NV ches enteednpaesunteneebenoance mated 1872, Mar. 23 ANTISELL, 'THOMAS........ ..| Patent Office. 1311 Q St. N. W........... 1871, Mar. 13 Avery, Robert Stanton........ .| Coast and Geodetie Survey Office. | 1879, Oct. 11 320 A St. S. E. Babcock, Orville Elias............... ..| 2024 G St. N. W .| 1871, June 9 Bailey, Theodorus (A) svtwosesasnnaxcacabect| Sexccess tnescescusanchnnes;aeseeasensnvay pater ye mpenet emer 1873, Mar. 1 BatrD, SPENCER FULLERTON......-..00000 Smithsonian Institution. 1445 Mass. 1871, Mar. 13 ve Ba Or sHv ans key resasscdesenaccosesansesSenssmend SZGC: Nisha, Wisseccecssenensuecesserenesscenecneane 1881, May 14 . Baker, Marcus....... ...| 347 Hill St., Los Angeles, Cal........ ...| 1876, Mar. 11 Bancroft, George SOB ED SiC Wiscssccecudecstesncrscusttectocnaeee 1875, Jan. 16 IBRRNES) 0 OSEPH IK) (0)iccesceasas son serescact| \senusousvaxaesceconsuaaputerseeesecehe 1871, Oct. 29 Loomis, Ben JenkS..cccseccceccseseseeees Nautical Almanac Office. 1413 Col- | 1880, Feb. 14 lege Hill Terrace N. W. Dull; Hdward Phelps <.........ccssssesssss. NEV) DGPATLOOMts.cccccke.saccetessesesesssbee 1875, Dec. 4 Lyford, Pater LO YS (© Bilata (fs nuruc vece st siacn era lemarracctaswantpabersedes suaccvseraauncnxereseat spnctavesss 1873, Jan. 18 MacCauley, Henry Clay (@).........+++ Helena, Montana... ..-|*>-"= £ggi ‘9g Areniqa,y poysodap pue So § ---- Areyaroag aaqn "yD | gl | 9 Qe ‘AON 60; Se= =e €ggr ‘1 Areniqa,z poysodap pur oS It ~~ saajurid ‘raplamjoq 2 ppnf{ | ZZ | oz oun{ oo Sfi¢g |---zggr ‘fz saquis90q7 paytsodap pure ol oF ~~ qomsvaly, ‘aqqy purpaasg,y | o£ | ¥ gz Judy : pealsdoi sonp yenuuy |} go dir |-~ saaqutad ‘xapiaajaqy 3» ppnf{ | SZ | £ Iz judy LOVER Ao To ZQQI *Qz ‘99 WOAJ ADAO potiies sduL[vg || oS SF ~~ sxoquud ‘rapraajaq 2 ppn{ | SZ | z Iz judy > SMOT[OJ sv s}diadaa Aq ytparD oo o9f = | ~~ saaquid ‘1ayramjoqy 9 ppnf{ | PL | 1 I yorey "Egg ‘ Qal\< 12}, ‘yunowy *90INOS JeYM UII] ‘yunowy ‘pred woya OJ, @ 2 ‘aed a ae “SLAIDOaY “SHUN LIGNAdXY "ag ERR aah ay] 40f ‘4aansva4y, ‘2qgQP puvjanay ypin sunorIv Ur UOjSuLmsygy fo Ajar205 pvrrydosojiyg YJ ‘Ad Oe”, BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. ANNUAL ADDRESS OF THE PRESIDENT. XXV ANNUAL ADDRESS OF’ THE PRESIDENT, J. W. Powe tt, Delivered December 8, 1883. THE THREE METHODS OF EVOLUTION. In the early history of research attention was chiefly given to phenomena of co-existence. In late years the phenomena of sequence have received the larger share of attention. The investigation of the phenomena of sequence has led to.the invention of a number of hypotheses. In the past history of scientific research three of these have each led to a long series of important discoveries. These are the nebular hypothesis, the atomic hypothesis, and the hypothesis of the development of life. The nebular theory is an hypothesis of astronomic evolution; the atomic theory has gradually assumed the shape of an hypothesis of chemical evolution; and the develop- ment theory has been elaborated and re-stated as the hypothesis of biologic evolution. The time has come when in all fruitful research evolution in some form is postulated by each investigator in his own field. Yet many scientific men, though admitting the doctrines of evolution in their own special fields, ofttimes reject them elsewhere; and there is some disagreement even among the greatest thinkers as to the extent to which the hypotheses of evolution can be carried, but all postulate evolution in some form and to some degree. An attempt will be made in this address to point out what is be- lieved to be the fact—that there are three grand classes of phe- nomena, constituting three kingdoms of matter and representing three stages of evolution; or, stated in another way, that there has been an evolution of the methods of evolution, so that the methods discovered in the first stage have been superseded by those discov- red in the second, and these superseded by the methods of the third stage. It is proposed to indicate and, as clearly as possible within the limits of an address, to define, in terms of matter and motion, the three kingdoms of matter and the three methods of evolution. — As precedent to the general statement it will be well, therefore, briefly to consider the kinematic hypothesis. XXVII XXVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. THE KINEMATIC HYPOTHESIS. That motion is persistent is the kinematic hypothesis. In the early history of research many modes or varieties of motion were directly observed. To account for these motions they were said to be caused by forces, and Force was sometimes defined as that which produces motion. Something, therefore, was conceived to exist— not matter, not motion—an existence that would produce motion. Then arose the question, What is Force—this antecedent of Motion? The researches inaugurated from this standpoint led again and again to the discovery that the antecedent of motion is some other motion, and one after another of the so-called “forces” were thus resolved into motions, until at last only gravity and affinity, and perhaps magnetism, remain as unexplained antecedents of motion. But gravity, affinity, and magnetism are included under one term, “ attraction,” by those who hold that there is yet a force—something other than motion which produces motion. Attraction, then, is left. Sometimes these same philosophers speak of “ attraction and repul- sion.” If, then, all forces the actions of which are thoroughly known are resolved into antecedent motions, it is indeed an induc- tive hypothesis worthy of consideration that the antecedents of the phenomena of attraction and repulsion may also be regarded as modes of motion. But this hypothesis is reached by another method. It is known that motions may be transmuted from one kind or mode into an- other.. Affinity can be transmuted into motion, and motion into affinity. If we wish to obtain the mode of motion called electricity, we may derive it from mechanical motion through friction, or we may derive it through affinity in the voltaic cell. If we combine a gramme of hydrogen with oxygen, 34,000 units of heat—a mode of motion—are developed. If a gramme of hydrogen be combined with iodine, 3,600 units of heat—a mode of motion—are absorbed. But why introduce single illustrations? A large part of all the powers used by man in the industries of the world are derived from affinity. Affinity, therefore, is the equivalent of motion. By a similar process it is shown that gravity can be transmuted into mo- tion and motion into gravity, and the trasmutation of magnetism into motion and of motion into magnetism is well known. It is thus seen that while motion may be derived from the so- called forces, gravity, affinity, and magnetism, these so-called force ANNUAL ADDRESS OF THE PRESIDENT. XxXIX may also be derived from motion. In all other cases where a mode of motion is transmuted, it is but changed into another mode. It is therefore an inductive hypothesis that gravity, affinity, and mag- netism are also modes of motion. This hypothesis is reached by yet another inductive process. There is a vast multiplicity of properties which bodies present to the mind through touch, taste, smell, hearing, and sight—properties at first explained as occult. During the progress of scientific re- search, one after another of these properties has been resolved into motion, until at last two remain unexplained—rigidity and elasticity. By those who hold with most tenacity to older explanations of such phenomena, these two remaining properties are attributed to attrac- tion and repulsion; but those who have fallen into the current of modern thought believe that they can be explained as the results of the composed motion of the constituent parts of the bodies which exhibit them, together with molecular impact. That some such ex- planation will eventually be fully established is highly probable as an inductive hypothesis. When these various methods of induction are combined they lead to an hypothesis of the highest character,and we may reasonably expect that all forces will ultimately be resolved into motions. The term force will still be of value in science, to be used in each case as denoting the antecedent motion. Intimately related to the kinematic hypothesis is the hypothesis of an ether, which has also been reached by a variety of inductive methods, 7. e. from converging lines of research. In fact, the kine- matic hypothesis and the ethereal hypothesis are identical, the first being stated in terms of motion, the second in terms of matter. Intimately related to the ethereal hypothesis is the nebular hypo- thesis, also reached through a series of converging lines of induc- tion. Every fact that lends probability to one lends probability to all. Thus each strengthens the other. It must be understood that how- ever probable they may be, they are yet hypotheses, and for their complete demonstration the mode of action must be specifically pointed out in each case. The ethereal hypothesis furnishes the original homogeneous matter in motion from which the various aggregates have been segregated. The nebular hypothesis takes up this matter while it is yet in a 3 a XXX PHILOSOPHICAL SOCIETY OF WASHINGTON. molecular condition and derives from it the more compounded ag- gregates and their motions, in obedience to the law of the persis- tence of motion, which is the kinematic hypothesis. Thus there are bodies of men engaged in researches relating to molecular physics, other bodies of men in researches relating to molecular physics and astronomy, and others in molecular physics and chemistry, all of whose researches converge in the kinematic hypothesis. It is there- fore reached by a consilience of many inductive methods. In the statement thus made concerning the kinematic theory there is no attempt to assemble the data on which it rests. Such task could not be performed in an address, as volumes would be ~ needed for their presentation. An attempt has been made simply to characterize the processes of inductive reasoning by which the hypothesis is reached. If the kinematic hypothesis should be demonstrated, it would be a veritable explanation. The dynamic hypothesis is no explana- tion. To exhibit this fact it must be briefly analyzed. Philosophy is the science of opinion, and the philosopher has for the subject-matter of his science the origin and nature of opinions, and he discovers that they may be broadly grouped in three classes— mythic, metaphysic, and scientific. Mythic opinion arises from the attempt to explain the simple in terms of the compound—that is, to explain biotic and physical phenomena by their crude analogies to human activities. Early man, discovering that his own activi- ties arose from design and will, supposed that there was design and will in all function and motion. Through this method of explana- tion have arisen the mythologies of the world. But in the early civilization of the Aryan race a multitude of mythic systems were thrown together and studied by the same body of men, originally for the purpose of deriving therefrom the com- mon truth. The resulting comparison and investigation led to the conclusion that they were all false, and in lieu thereof a new system of explanation was invented. These earlier philosophers of the cities of the Mediterranean, while engaged in the comparison of mythologies, were also engaged in the comparison of languages, and they discovered many profoundly interesting facts of linguistic structure, and the intimate relations between language and thought by which the form of thought itself is moulded. These great facts appearing at the same time that mythic philosophy was dis- ANNUAL ADDRESS OF THE PRESIDENT. XXXI solving into idle tales, led to the origin of a new philosophic method. The men of that day supposed that the truth is in the word, and that a verbal explanation could be constructed ; that the philosophy of the universe could be based on language; and to them verbal statement was explanation, final and absolute, and be- ing was but ideal. But metaphysic philosophy was displaced by the increase of knowledge—the development of scientific philosophy. In this sys- tem the phenomena of co-existence and sequence are objectively discerned and classified. This bare statement of the three methods can be made more lucid by an illustration. Unsupported bodies above the earth fall, and such phenomena are seen so often as to challenge every man’s atten- tion. Early man, whose mind was controlled by mythic opinions, subjectively knew that if he wished to move a body he must push or pull it, and to him there was no other method of originating motion. Some years ago I was with a small body of Wintun Indians on Pitt River, the chief tributary of the Sacramento, engaged in the study of mythology. I had gone among the rocks for the purpose of awakening echoes, that I might elicit from my dusky philosophers an explanation thereof. Unexpectedly I fell upon an explanation of gravity. We had climbed a high crag, and I sat at the summit of the cliff with my feet overhanging the brink. An Indian near me, who could speak but imperfect English, seemed solicitous for my safety, and said: “ You better get out; hollow pull you down.” I had previously been intent on watching the operations of his mind for the purpose above mentioned, and this expression seemed to me strange; and it started a line of investigation which I eagerly pur- sued. I soon discovered that he interpreted the fall of bodies by purely subjective analogies. He who stands on a rock but slightly elevated above the earth feels no fear, but if standing a thousand feet above the base of the cliff, he attempts to look over, fear curdles his blood, and he seems to be pulled over. As he climbs a lofty pine, at every increase of altitude there is an increase of fear, and he seems to be pulled down by a stronger force. When he rests upon the solid earth he feels no “ pull,” but when elevated above it he interprets. his subjective feelings as an objective pull. Vacuity is personified and believed to be an actor. In the early winter of 1882 I was with a party of Indians in the XXXIT PHILOSOPHICAL SOCIETY OF WASHINGTON. Grand Cafion of the Colorado. Some of the young men were amusing themselves by trying to throw stones across a lateral gorge. No one could accomplish the feat, though they could throw stones even farther, as they believed, along the level land. Chuar, the chief, explained this to me by informing me that the cafion pulled the stones down. The apparent proximity of the opposite wall was believed to be actual, and vacuity was personified and believed to exert a force. ; : Metaphysic explanations of gravity are found. By that method an absolute up and down is predicated, and bodies have a tendency to fall down. This is an explanation in words, the words expressing no meaning but believed to be themselves thoughts. It is per- haps the earliest form of the metaphysic explanation of gravity. But with the progress of knowledge the absolute disappears, and positions are found to be but relative ; there is no absolute up and down; and other facts with regard to gravity are discovered. And finally the metaphysician says bodies attract. Now the term fall, as used by the early metaphysicians, was the name of a motion observed, and it was held to be a complete explanation as long as up and down was supposed to be absolute, not relative; and the explanation was abandoned as insufficient when the ideas of abso- lute up and down were abandoned. But the word attraction does not involve this error. It is simply a name for the phenomenon, without the manifestly fallacious implication of “‘up and down.” And it is a good name for the specific phenomenon to which it is applied. But it must not connotate any other idea; in so far as it does, it is vitiated. Yet the metaphysician will suppose that by using the term “attraction” he explains gravity. The scientific philosopher uses the term purely as the name of the phenomenon, and does not suppose that thereby the phenomenon is explained ; and having named it, he still seeks for its explanation—that is, he still seeks to resolve that which is manifestly a complex phenom- enon, exhibited in the relations of positions of bodies, into its most simple elements. Whenever this is done he will say that attraction, or gravity—they being synonyms for the same phenomenon—is explained. The kinematist uses “attraction” asasynonym for “ gravitation.” The dynamist uses “attraction” as a verbal explanation of Gravi- tation. The mythic philosopher uses the term to connotate the still further idea that bodies exert a “ pull” on one another; and this ANNUAL ADDRESS OF THE PRESIDENT. XX XIII latter concept is no less mythic than that of the Indian who believes that the vacuity between them exerts the pull. It is fortunate for science that every discovery and every induc- tive hypothesis is rigidly criticised, as this leads to the careful examination of the verity of facts discerned and of the legitimacy of hypotheses derived therefrom. Against the kinematic theory of force much good rhetoric has been hurled, which may be somewhat imitated in the following manner : Here is a quotation from Bagehot, with an interpolation of my own: “This easy hypothesis of. special creation [occult force] has been tried so often, and has broken down so very often, that in no case probably do any great number of careful inquirers very firmly believe it. They may accept it provisionally, as the best hypothesis at present, but they feel about it as they cannot help feeling as to an army which has always been beaten; however strong it seems they think it will be beaten again.” The venerable gentlemen who constitute the elder school tell us that motion is not persistent; that energy constitutes a class of things including two groups, the forces on the one hand and the motions on the other; that the total amount of energy is persistent, but that the total amount of motion is changeable. And by their definition force is that which produces motion, 7. e. force can create or destroy motion. But manifestly where there is more motion there must be less force, therefore force can destroy itself; and when there is more force and less motion, force can create itself. The moon that passes through the sky of the gentlemen of the old school is moon from the eastern to the western horizon. Then the dragon, which exists not, destroys the moon and thus creates itself, and passing through the cave from west to east it mounts to their horizon, and in the twinkling of an eye commits suicide by creating a moon. It is not strange that the thaumaturgics of such philosophy should lend signal aid to its rhetoric. The use of hypothesis in science is not only legitimate but an absolute necessity. The science of psychology, as distinguished from metaphysic speculation, points out this fact: that all increase of knowledge is dependent upon hypothesis. Objective impressions made by the phenomena of the universe upon the organ of the mind are discerned only by the aid of comparison, and are added to knowledge only by being combined with previously discerned phe- é XXXIV PHILOSOPHICAL SOCIETY OF WASHINGTON. nomena. Phenomena imperfectly discerned are such as are com- bined by superficial analogies; phenomena clearly discerned are such as are combined by essential homologies. With all discern- ment, therefore, there is comparison, and comparison is reflection and reflection is reason. Now, scientific research is not random observation and comparison, but designed discernment and classifi- tion ; it is research for a purpose, and the purpose is the explanation of imperfectly discerned phenomena. Phenomena not understood, because imperfectly discerned and classified, are made the subject of examination by first inventing a hypothetic explanation of the same. With this, the investigator proceeds to more careful obser- vation and comparison, devising new methods of discrimination and of testing conclusions. Under the impetus of this hypothetic explanation, discernment and comparison proceed, and additions to knowledge are made thereby, and it matters not whether the hypo- thesis bé confirmed or overthrown. On this rock much research is wrecked. When an hypothesis gains such control over the mind that phenomena are subjectively discerned, that they are seen only in the light of the preconceived idea, then research but adds to vain speculation. A mind con- trolled by an hypothesis is to that extent insane; the rational mind is controlled only by the facts, and contradicted hypotheses vanish in their light. There is another rock on which research is wrecked—the belief which ofttimes takes possession of the mind that the unknown is unknowable, that human research can penetrate into the secrets of the universe no farther. It is the despondency of unrewarded mental toil. Yet another rock on which research is wrecked is the definition of the unknown. Phenomena appear, but whence is not discovered, and resort is had to verbal statement, and the verbal statement oft repeated comes to be held as a fact itself. This is the vice of all metaphysics, by which words are held to be things—spectral imagin- ings that haunt the minds of introverted thinkers as devils possess the imaginations of the depraved. In the midst of the sea of the unknown stand the three rocks: the controlling hypothesis, the unknowable unknown, and the verbal definition, and in the waters about them are buried many wrecks. % ANNUAL ADDRESS OF THE PRESIDENT. XXxXV COMBINATION OF MATTER. When the various bodies known to mind are resolved into their constituent parts to the utmost of art and knowledge, such parts are found to be so minute as almost to disappear in the perspective toward the infinitesimal. The molecular bodies thus dimly discerned ‘are combined and re-combined, until substances are produced that come distinctly within the cognizance of our senses, so that we are able to observe their forms and motions. These molar bodies are again combined, until at last bodies of such magnitude are pro- duced that they are but dimly discerned in the perspective toward the infinite—stellar systems that appear not to the eye, but only to the mind’s eye. INORGANIC COMBINATION. Matter is primarily combined by chemical affinity. The sub stances thus produced appear in three states: gaseous, fluid, and solid, but are not clearly demarcated. That chemically combined matter which is found in the solid state is further combined by crys- tallization and lithifaction. It may be that these methods are parts of the same process, and further, that they are one with chemical affinity ; at any rate it is impossible clearly to demarcate them. - They are also influenced by gravity, and to a large extent act under its control. Thus it is that gravity, and affinity with its concomi- tants, unite in molecularly combining matter into inorganic sub- stances. Again, these bodies are mechanically combined into geo- logic formations, bodies of water, and bodies of air, and such com- binations result from gravity. Finally they are all combined into an aggregate, the earth itself, solid, fluid, and gaseous. This also results from gravity. In the succession of combinations thus briefly reviewed, the first natural aggregate reached is the earth. Below that we have chemi- cal and mechanical substances, which do not constitute integers, but only integral parts. The earth itself is a whole—an aggregation, as the term is here used. Again, the earth is one of the bodies of the solar system, which is a combination of worlds. This aggregation, also, is controlled by gravity. Other higher astronomic aggregates may exist. ORGANIC COMBINATION. Portions of the matter combined by affinity and gravity are seg- LIBRARY } SEP 6 J888 1 LW we see SND DWIID XXXVI PHILOSOPHICAL SOCIETY OF WASHINGTON. regated to be combined by vitality, giving organic bodies or aggre- gates, as plants and animals. These bodies do not permanently re- main such, as the matter of which they are composed sooner or later returns to the condition of combination due solely to affinity and gravity. They live and die. SUPERORGANIC COMBINATION. There are certain biotic bodies whose activities are combined. The first step in combination is the biologic differentiation of the sexes, giving a group of co-operative individuals for the activities of reproduction—male and female, parent and child. This initial combination is crudely developed into still larger combinations of co-operative individuals among the lower animals. With mankind it is developed to a much higher degree, resulting in a great variety of co-operative activities. There is found, then, a variety of methods of combination, in- cluded under three classes: physical, due to affinity and gravity; biotic, due to vital organization; and anthropic, due to related actiy- ities. Physical combinations result in the production of substances and aggregates, and the existence of a physical body is preserved by preserving identity of form and identity of constituent matter. Biotic combination also produces substances and aggregates, and the existence of a biotic body is continued by the preservation of identity of form, but not of identity of constituent matter. In an- thropic combination, substances and aggregates, as the terms are here used, are not produced, but biotic aggregates are interrelated in their activities through the agency of mind. In physical aggregates the relation of parts is that of interde- pendence, so that the constitution and form of each part are de- pendent on the constitution and form of every other part. This interdependence may be better comprehended by means of an illus- tration. In the aggregate the earth, the interdependence is exhib- ited in the relations existing between the incompletely aggregated bodies of minerals, known as geologic formations; the incompletely aggregated bodies of water, known as seas, lakes, streams, and clouds; and the incompletely aggregated bodies of air, known as winds. Air-currents gather the waters from the seas and pour them upon the lands. Rains and rivers disintegrate the rocks and carry them to the sea. Currents in the sea distribute the detritus over ANNUAL ADDRESS OF THE PRESIDENT. XXXVII the bottom. By the loading of areas of sea-bottom they are de- pressed, and by the degradation of land-areas they are unloaded and rise. Change in the geography of the land effects a change in wind-currents and in bodies of water, and a change in the latter effects a change in sedimentation. In like manner, throughout all physical nature, an interdependence of parts is exhibited. Part acts on part. In biotic aggregates the same interdependence of parts is shown. Any change affecting the digestive apparatus affects the circulatory apparatus, and these again are influenced by the respiratory appara- tus. But in addition to this interdependence of parts, there is also an organization of parts—that is, special functions are performed by the several parts, and each is the organ of its function. And this organization is of such a nature that each works for the others. The digestive apparatus digests for itself and all the organs, the heart propels for all the body, the eye sees for all the body, the ear hears for all the body, the hand touches for all the body. Thus the organic parts act on and for one another. In activital combination, aggregates, as the term is here used, do not appear, but the same interdependence is observed. By associa- tion the sanitary state of the husband affects that of the wife, and the condition of the mother affects the child; and on through the different combinations of animals and men this interdependence is observed. The relation of organization also exists by the differen- tiation of industries. The husband brings food to the wife and children, and the wife prepares the food. And this differentiation of industries, or “division of labor” as it is termed in political science, is carried on to an elaborate condition in civilized life. Then men are related to one another as constituent members of society ; one commands and another obeys. Then men are related to one another through language; one speaks, another hears; one writes, another reads. Then men are related to one another through opinions; having common opinions, they form common designs and act for common purposes. It will thus be seen that superorganic or an- thropic combination arises trom the establishment of four classes of relations, corresponding to the four classes of activities represented by arts, institutions, languages, and opinions. The arts are human activities directed to the utilization of the materials of nature and the control of its powers, for the purpose of securing happiness. In- . stitutions are human activities arranged for the purpose of securing ~ XXXVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. peace and establishing justice, and thereby increasing happiness Languages are activities devised for the purpose of communicating thought, and thereby securing happiness. Opinions arise from psychic activities, the purpose of which is to learn the truth, that happiness may ensue. In physical, biotic, and anthropic combinations the parts control one another. It will therefore be convenient to speak of three ‘kingdoms of matter: the mineral or physical kingdom, the organic or biotic kingdom, and the anthropic or activital kingdom. MODES OF MOTION. All bodies, however combined, are discovered to be in motion. Among the bodies of the mineral kingdom, a variety of modes of molecular motion are exhibited, having various distinguishing characteristics. These are heat and light, electricity and magnetism, then sound and that motion in gases by which through impact they retain their rarefied state. Again, a variety of molar motions are observed in gases, liquids, and solids; and finally stellar motions are observed in astronomic systems. In the biotic kingdom plants and animals exhibit many varieties of organic motions, called functions. These are superadded to the physical motions, which appear alike in the physical and biotic kingdoms. Physical bodies exhibit motions; biotic bodies exhibit motions and functions, the latter being highly organized motions. In the anthropic kingdom there is a complexity of motions arising from biotic functions, which are arranged and combined so as to produce activities. These activities are represented by arts, institu- tions, languages, and opinions. Thus there are three great classes of motions corresponding to the three great classes of combinations, namely, physical motions ; biotic motions, or functions; and anthropic motions, or activities. THE RELATION OF MOTION TO COMBINATION. It will at once be seen that anthropic combination,is such by virtue of human activities. Activital combination is manifestly composed motion. Again, biotic aggregates are such by virtue of continuous combi- nation and dissolution. Within proper limits a biotic body may be compared to a river; it is a form through which matter passes. In ANNUAL ADDRESS OF THE PRESIDENT. XXXIX plants some of this passing matter becomes fixed for a time, but eventually returns from the biotic to the mineral kingdom. Among animals this passage of physical matter through the biotic form is more rapid. The organic functions, also, of these bodies are but arranged or organized motions. Life is motion—the specific motion called function. Again, among the aggregations of the physical kingdom, stellar systems are aggregates by virtue of motion. The combination ob- served is due to composed motion. Of the mechanical combina- tions, that exhibited in the atmosphere is such by virtue of motion— that is, the gaseous state is preserved by the interference of molecu- ° lar motions, and the bodies into which it is imperfectly differen- tiated, 7. ¢., currents of air, are such by virtue of motion. Again, the imperfectly aggfegated bodies of water are such by virtue of motion. This is seen to be true of the clouds floating in the air, and of rivers rolling to the seas. Lakes with outlets are bodies of water in motion, forever fed from the clouds, forever discharging into the sea; and mediterranean seas without outlet are perpetually receiving and discharging their waters; and so far as the sea is differentiated into currents, these are bodies imperfectly aggregated by motion. There yet remain certain molecular combinations of inorganic substances, due to affinity and gravity, the nature of which is not so immediately perceived. Now, as all societies and other anthropic combinations are such by virtue of their motions, known as activi- ties, and as all biotic bodies are such by virtue of their functions, and as all stellar combinations are such by virtue of stellar motion, and as finally all mechanical combinations are such by virtue of motion, it is at once suggested as an inductive hypothesis that those combinations the nature of which is yet unknown are also such by virtue of motion. It is an hypothesis worthy of consideration, that affinity and gravity are also due to motion. It has even been sup- posed by some that chemical and barologic methods of combination are but diverse modes of the same process; that affinity and gravity constitute but one method of combination, and that we call it affinity when the combination involves minute bodies, below our sense perceptions, and gravity when larger bodies are involved. An attempt has thus been made to define the three kingdoms of matter in terms of matter and motion, showing that there are three XL PHILOSOPHICAL SOCIETY OF WASHINGTON methods of combination, and that the parts combined are related by three corresponding methods, and that in each kingdom motions of a distinctive class are discovered. The constitution of physical bodies is due to composed motion; the constitution of biotic bodies is due to composed transmutations of motion; anthropic combina- tions are due to related activities. In order that there be evolution, there must be change in com- bination of matter and in mode of motion. The sole property of matter is motion, and motion itself is change of position. But this change of position results in change of combination, and change of combination results in change of mode of motion. These changes must now be set forth. CHANGE OF COMBINATION. If the mind could discern and classify all the bodies of the uni- verse at any one moment, only space conditions would enter therein ; but bodies change from time to time, so that there are sequences of combination. Substances and aggregates of matter are such by rea- son of an arrangement in position of their constituent parts. Sub- stances and bodies change in external relations and in internal rela- tions. Change in external relations is change of position in relation to external things. Change in internal relations is the change in relative arrangement of constituent parts. And this change of posi- tion is always motion, the first and only property of matter. Chemical, crystalline, and lithical combinations are decomposed and otherwise re-composed, mechanical combinations are broken up and otherwise re-arranged, and stellar aggregates are believed to have been gradually formed. With physical bodies internal change is the direct result of external change. This is their dis- tinctive characteristic, that all their changes of constitution result directly from agencies without themselves. Biotic bodies exhibit the same changes as mineral bodies, and also a series peculiar to themselves. First, biotic substances are segregated from the mineral kingdom—. e., mineral substances are changed into biotic substances. Second, biotic bodies begin, grow, decline, and die. This is a progressive change of structure. Third, the structure of biotic bodies is preserved by continuous change in their constituent matter. Form and structure are preserved while the matter is forever changing. Life is a determined, systematic sequence of transmutations of motion, transformations of matter, and ANNUAL ADDRESS OF THE PRESIDENT. XLI transfigurations of body. Life is change. Fourth, as the individ- uals are not persistent, the method of aggregation continues by the processes of reproduction of like forms. But these like forms are made unlike—. e., changed—by two processes. In the biotic repro- duction of the higher forms the bisexual method prevails, so that each individual is the offspring of two parents, like both so far as they are alike, but differing from the one or the other so far as they are unlike. Fifth, the individual has its constitution determined by its parents, but subject to changes which may be brought about by external relations differing from those to which the parents were subjected ; and within limits these are transmitted to offspring. Thus it is seen that biotic changes are caused by external and in- ternal agencies. This may be put in another form. In mineral bodies the same matter is changed in structure. In biotic bodies the same or nearly the same structure remains and the constituent matter changes; yet there is a slow change in structure from birth to death, and a still further change in structure from generation to generation; but there is more rapid change of constituent matter. Anthropic ag- gregates arise, not by a combination of matter, but by a combina- tion of the activities of biotic bodies. These biotic bodies them- selves change, as individuals disappear and new ones take their places. Thus family group succeeds family group, and generations of people succeed generations of people. In the same manner arts change. Old arts are abandoned and new arts appear. Various societies cease to exist and new societies are organized. ‘The organ- ization due to the differentiation of operations steadily increases by the division of labor; and the grouping of bodies of men into states, i. €., tribes and nations, is in constant flux. So, languages change— they grow and die. And opinions change with each individual and from generation to generation. All these changes are determined by the will of the individual units who are actors—that is, activi- ties change because the actors so desire. Anthropic change is due to psychic agencies. CHANGE OF MOTION. That motion is persistent is a fundamental axiom. But while it does not change in quantity it changes in quality in diverse ways. First, motion may be changed in direction. Simple motion is the motion of a body in a straight line, and change of such motion of XLII PHILOSOPHICAL SOCIETY OF WASHINGTON. the lowest order is change in direction, and this is accomplished by the combination of two or more motions having different directions. Then motion may be transmitted from one body to another. The molecular motions—heat, light, electricity, sound, ete—are motions propagated by transmission from molecule to molecule. In the kinematic hypothesis of gravity it is held that atomic motion is transmitted from atoms to combined and aggregated bodies by im- pact; and here we reach another method of change—that by trans- mutation. One mode of motion may be transmuted into another, as molar motion into heat, and heat into electricity. By the combination of matter motion iscomposed. Mineral sub- stances and aggregates exhibit this composition of diverse modes of motion. Biotic bodies exhibit composition of modes of motion, and also composition of transmutations of motion, ‘and it is this latter characteristic which distinguishes biotic from physical motion. Activital combinations exhibit a composition of modes of motion, and a composition of the transmutations of motion, and a compo- sition by co-operative action. It is the last characteristic which distinguishes activital motion from biotic. The changes of motion exhibited in the mineral kingdom are changes in direction by combination, changes in relative quantity by transmission, changes in mode of motion through transmutation, and changes in the combination of modes of motion. In the biotic kingdom the same changes are found as in the min- eral kingdom, but to them are added changes in the composition of transmutations of motion. In the anthropic kingdom all the changes in the other kingdoms appear, together with changes in the composition of activities. EVOLUTION DEFINED. As matter is indestructible, when one combination or aggregation is dissolved some other must appear, and vice versa. Existing bodies must have antecedents. In tracing backward the history of bodies, lines of sequences are followed. Many such are known, and the first important characteristic to. be noted of them is they are orderly. ike bodies have like antecedents. From this results one of the highest inductions of science, namely, that from consequents antecedents can be restored, and from antecedents consequents can be predicted. The second important characteristic of these sequences ANNUAL ADDRESS OF THE PRESIDENT. xXLiUt of change is that many are in a definite direction, which is gradually becoming known. This general course of change is denominated Evolution, and the term must be defined. Evolution is progress in systemization. It must be noted that not all changes are progressive; some are retrogressive. It is only progressive change that is here called evolution; retrogressive change is dissolution. As the term is here used, a System is an assemblage of interdependent parts, each arranged in subordination to the whole so as to constitute an integer. Evolution may therefore be defined in another way. It is progress in differentiation by the establishment of unlike parts, and in the integration of these parts by the establishment of interdependence. Dissolution is retrogres- sion by the lapsing of integration through the destruction of inter- dependence, and the lapsing of differentiation through the loss of heterogeneity in parts. EVOLUTION IN THE PHYSICAL KINGDOM. Under the kinematic hypothesis, which embraces the ethereal and nebular hypotheses, portions of discrete matter have been segregated to be combined and aggregated. The process precedent to evolu- tion, then, is combination and aggregation, by which substauces and integers are produced. Whatever may be the fate of the explanation of the origin of substances and aggregates through the kinematic and concomitant hypotheses, the fact remains that such bodies exist, and the evolu- tion of matter, as it is hereafter dealt with, starts from this point. Given substances and aggregates as they are known to exist in nature, and given changes which they are known to undergo, it is proposed to point out by what methods evolution is attained. The terms substance and aggregate have been used as distin- guishing two orders of combination. It should be noted that they cannot be clearly demarcated. Substances are composed of homo- geneous, non-interdependent parts, but this homogeneity is never absolute, and some slight degree of interdependence may always be discovered. Aggregates, on the other hand, are composed of hetero- geneous, interdependent parts, but degrees of heterogeneity and interdependence appear. Combination is the bringing together of dissociated matter; and it is in the combinations, separations, and re-combinations of matter that evolution appears. > XLIV PHILOSOPHICAL SOCIETY OF WASHINGTON. In mineral bodies combinations proceed by molecular, molar, and stellar methods. It has been shown that the changes in these bodies are due to external conditions or forces. If a given body be in harmony with external conditions no change occurs in its constitu- tion, but if it be out of harmony the impinging agencies effect such modifications as will produce harmony. This may be done by a change in the body as a substance or aggregate, or by its separation and re-combination in some more harmonious form. The evolution of mineral bodies is thus accomplished by direct adaptation to external conditions. If it is permitted hypothetically to conceive of a universe of ethereal matter—i. e., matter composed of discrete atoms in motion, such atoms would remain in an attenuated condition by atomic im- pact. In matter thus constituted, motion could be transmitted from atom to atom, but no new mode of motion would result therefrom. The mass of matter thus constituted would be absolutely homoge- neous. But if by some method several such atoms should be com- bined, so as to move together as a common body, and so that their interspaces could not be penetrated by other atoms, the motion of an impinging atom would not only be transmitted to the larger body, but it would also be transmuted into another mode or kind of motion. If other such molecules were formed by the segregation of atoms from the homogeneous mass, the new kind of motion would be set up in all the matter thus segregated, and the motions of these bodies would react one upon another. If, again, some of these molecules were segregated, to be combined in larger bodies, with or without such a diminution of interspaces as to prevent the inter- penetration of atoms, a third mode of motion would be established ; and if diverse methods of aggregation should occur, diverse modes of motion would be established thereby; and in all combining and re-combining, aggregating and re-aggregating, new modes and com- plexities would arise. It is a well-known law that a moving body passes in the direction of the least resistance. Diverse modes of motion may exist in a body, due to the complexities of its organization. Im the trans- mission of motion to such a body from another by impact, the motion transmitted is transmuted into that mode which gives it the least resistance. This is illustrated on every hand. When a smaller body impinges against a larger, the inequality between the two may be so great that molar motion is not set up in the ANNUAL ADDRESS OF THE PRESIDENT. XLV larger body, but the whole of the imparted motion is transmuted into heat or some other melecular motion. This law, that motion passes in the direction of least résistance, is the equivalent of the law of adaptation in the evolution of mat- ter. When evolution is considered from the standpoint of matter, it is convenient to use the term Adaptation ; when considered from the standpoint of motion, it is more convenient to use the term Least Resistance. EVOLUTION IN THE BIOTIC KINGDOM. In biotic bodies it has been seen that change is the result of in- ternal as well as external conditions. As external conditions, or the environment, are changing, these bodies change to a limited extent, in the same manner as do mineral bodies; but there is also a change brought about indirectly by the environment, through certain in- ternal changes in the constitution of biotic bodies. Through this internal constitution individuals are changed in time—one genera- tion dies and another succeeds. There is yet another method of change in biotic bodies, which steadily increases from the lowest to the highest—that is, the change in their constituent matter. While structure changes slowly from birth through growth and decadence to death, the constituent matter changes with much greater rapidity. In this change the minute elements of structure change much more rapidly than the larger into which they are compounded ; so that every part of the organ must be supplied with new material to replace that which is steadily becoming effete and passing away. Now the rate of this change in any integral part of an organism is dependent upon the activity of the organ. Exercise increases the rate of change in the constituent matter of a biotic organ, and thus the slow change in its structure, which proceeds from life to death, is accelerated. This accelerated change results in increased differentiation of the organ, and it thereby becomes more and more efficient in the performance of its function. This change, therefore, results from exercise. Organs that are ex- ercised increase in efficiency, by non-exercise they decrease in effi- ciency. This change in the organization of any one individual is but slight, but as the slight changes pass from one generation to’ another, continuous exercise of one set of organs greatly modifies them; continuous neglect of exercise in another set modifies them also, until at last they are atrophied. Thus by exercise and non- 4a XLVI PHILOSOPHICAL SOCIETY OF WASHINGTON. exercise important structural changes are produced when conjoined with the changes due to heredity. All these changes result in progress, from the fact that those indi- viduals whose change is in a direction out of harmony with the en- vironment ultimately perish, while those whose change is in a direc- tion in harmony with the environment survive. This method of adaptation or evolution in biology is called “ the survival of the fittest.” The rate of evolution by survival is greatly accelerated by another condition. Each pair of biotic bodies reproduce a large number of new bodies, so that reproduction from generation to generation is in a high geometric ratio. The earth having become occupied with all the biotic beings that can derive sustentation therefrom, but a small fraction of the beings produced in a generation can live. Few survive, many succumb. Survival by adaptation is therefore made more efficient by competition. There are other changes in the biotic kingdom brought about by adaptation. The multiplicity of biotic beings, causing over-popula- tion, has crowded them into every conceivable habitat—in the air, on the land, and in the water; and living beings have become adapted thereto by the development of wings, legs, fins, and correl- ative organs. Thus by exercise organs have been developed, and by non-exercise other organs have been atrophied, until living be- ings have become specialized for a vast diversity of habitats—for life on the mountain and in the valley, in the light and in the dark, in the cold and in the heat, in humid regions and in arid re- gions. Living beings have also been adapted to various kinds of food and to various methods of acquisition—in fine, to a great variety of conditions. This specialization by development, through exercise and non- exercise, must be clearly distinguished from the processes of evolu- tion. The heterogeneous living beings thus produced are but multi- plied and diverse forms, animals and plants alike being as often de- graded as evolved in the processes of specialization. Degradation is especially to be noticed in parasitic animals and others adapted to extremely abnormal habitats ; but it should be understood that a form thus produced may, in the process of its production and sub- sequent existence, make progressive change in the system of its structure by the methods of evolution already characterized. Specialization is greatly accelerated by a peculiar method. As ANNUAL ADDRESS OF THE PRESIDENT. XLVII all the highes animals are physically discrete, psychic relations must be established, in order that they may meet for the act of re- production. These psychic relations gradually develop into choice, or sexual selection, and by methods which have been clearly pointed out by biologists the minute increments of change that result there- from eventually accumulate into strong variations, always adapted to the conditions of the environment. Thus the survival of the fittest is accelerated by sexual selection. EVOLUTION IN THE ANTHROPIC KINGDOM. If attention is directed exclusively to animal life, we notice that evolution has proceeded pari passu with specialization. Of the forms that have been specialized from time to time some have be- come extinct, some have been degraded, and some have been evolved in varying degree. One form, not the most specialized, made the greatest progress in evolution, until an organism was developed of so high a grade that this species became more independent of en- vironment than any other, and, by reason of its superiority, spread widely throughout the land portion of the globe. This superior animal was early man, when he first inhabited all the continents and the great islands. The production of this superior, 7. e. more highly systematized organism, was the antecedent to the inauguration of new methods of evolution. It has been shown that the great efficiency of the biotic method of evolution by survival depends upon competition for existence in enormously overcrowded population. Man, having acquired superi- ority to other animals, passed beyond the stage when he had to compete with them for existence upon the earth and into the stage where he could utilize plants and animals alike for his own pur- poses. They could no longer crowd him out, and to that extent the law of the survival of the fittest in the struggle for existence was annulled in its application to man. - He artificially multiplies such of the lower animals as are most useful to him, and domesti- cates them, that they may be more thoroughly under his control, and modifies them, that they may be more useful, and uses such as he will for beasts of burden; and the wild beasts he destroys from the face of the earth. In like manner he cultivates useful plants, and destroys such as are worthless to him. He does not compete with other biotic species, but utilizes them for his wélfare. Yet XLVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. the law of the survival of the fittest applies in so far as it is not dependent upon competition, and slow evolution may still result therefrom. But at this stage new methods spring up of such great efficiency that the method by the survival of the fittest may be neglected because of its insignificance. In anthropic combinations the units are men, and men at this stage are no longer passive objects, but active subjects; and instead of man being passively adapted to the environment, he adapts the environment to himself through his activities. This is the essential characteristic of anthropic evolution. Adaptation becomes active instead of passive. In this change certain parts of the human or- ganism are increasingly exercised from generation to generation. This steadily increasing exercise results in steadily increasing development, and the progress of the unit—man—in this higher organization depends upon development through exercise. But the progress by exercise depends upon the evolution of activities. Man is an animal, and may be studied as such; and this branch of science belongs to biology. But man is more than an animal, Though an animal in biotic function, he is man in his anthropic activities ; for by them men are combined—1. e., interrelated—so that they are not discrete beings, but each acts on, for, and with, his fellow-man in the pursuit of happiness. Human activities, thus combined and organized, transcend the activities of the lower ani- mals to such a degree as to produce a new kingdom of matter. The nature of these activities must here be set forth. The first grand class is composed of those which affect the exter- nal world, and by them men are interrelated through their desires. These activities are the Arts. The arts have been evolved by human invention, and man has been impelled thereto by his endeavor to supply his wants. In the course of the evolution of the arts, man has progressively obtained control over the materials and powers of nature. All the arts of all the human period are the inventions of men. But invention has proceeded by minute increments of growth. A vast multiplicity of arts have been devised, of which compara- tively few survive in the highest civilization. As the inventions have been made, the best in the average has been chosen. Man has therefore exercised choice. The evolution of the arts has thus been by the method of invention and choice, in the endeavor to gratify desire, and by them man has adapted the environment to himself. Second. There is a grand class of activities through which men ANNUAL ADDRESS OF THE PRESIDENT. XLIX are interrelated in respect to their conduct. These activities result in Institutions. Through them men are associated for a variety of purposes. Every institution is an organization of a number of in- dividuals, who work together for a common purpose, as, for exam- ple, to prosecute some industrial enterprise, to co-operate in the pursuit of pleasure, to promote some system of opinions, or to wor- ship together under the forms of some religion. All such institu- tions constitute a class denominated Operative Institutions. A second class are the institutions which man has organized for the direct reg- ulation of conduct. These are States and their subordinate units, with their special organs of government, and rules for the regulation of conduct, called Laws. Institutions have been developed from extreme simplicity to ex- treme complexity. They are all the inventions of mankind, and their evolution has been by minute increments of growth. Their invention has been wrought out that men might live together in peace and render one another assistance; and gradually, by the consideration of particulars of conduct as they have arisen from time to time, men have sought to establish justice, that they might thereby secure peace. Of the vast multiplicity of institutions— forms of state, forms of government, and provisions of law—which have been invented, but few remain in the highest civilization, and these few have been selected’ by men. Men have thus exercised choice. Institutions, therefore, have been developed by invention and the choice of the just in the endeavor to secure peace. Third. There is another fundamental group of activities through which men are interrelated in respect to their thoughts. These are the activities of mental intercommunication, and result in Lan- guages. Languages, also, are inventions by minute increments of growth. Many languages have been invented, and in each language many words and many methods of combining linguistic devices have been invented. In the languages of the most civilized peoples, but few of these survive; and there are spoken by all the peoples of the earth but few languages in comparison to the many that existed in the early history of mankind; and the method of survival, when analyzed, is found also to be choice. Men have chosen the economic in the expression of thought. Languages, therefore, have devel- oped by invention and choice in the struggle for expression. Fourth. There is a grand class of activities by which men are interrelated in respect to their designs. Men arrive at Opinions, and L PHILOSOPHICAL SOCIETY OF WASHINGTON. these have always reacted upon languages, institutions, and arts, and largely led them in their courses of progress. Because of their opin- ions, men are willing to work together, and thus have common designs. There have been many opinions and many systems of philosophy. Of all that have existed, but few remain in the highest civilization. A careful analysis of the facts relating to the growth of opinions re- veals this truth, that opinions also are invented, and that the final survival of the few has been due to the human act of choice in the selection of the truth. Opinions, therefore, have been developed by invention and choice in the struggle to know. Fifth. Opinions are formed as the direct activities of the Mind. Languages, institutions, and arts have arisen through the action of the mind and the exercise of other corporeal functions. All these activities, therefore, are dependent upon the mind. On the other hand, these objective activities react upon the mind, so that mental operations are controlled thereby. Through the exercise of the mind in the prosecution of activities it is developed. These mental activities are perception and comparison, or reflection, as it is more usually called. The subjective evolution of the mind is therefore the product of the objective evolution of activities. These five great classes of activities are interdependent in such a manner that one is not possible without the others; they arise to- gether, and their history proceeds by a constant interchange of effects. All the five classes of activities react upon man as an ani- mal in such a manner that his biotic history subsequent to his differentiation from the lower animals is chiefly dependent thereon. The evolution of man as a being superior to the beast is therefore due to the organization of activities. It has been shown that man does not compete with the lower animals for existence. In like manner, man does not compete with man for existence; for by the development of activities men are interdependent in such a manner that the welfare of one depends upon the welfare of others ; andas men discover that welfare must necessarily be mutual, egoism is transmutted into altruism, and moral sentiments are developed which become the guiding princi- ples of mankind. So morality repeals the law of the survival of the fittest in the struggle for existence, and man is thus immeasur- ably superior to the beast. In animal evolution many are sacrificed for the benefit of the few. Among mankind the welfare of one depends upon the welfare of all, because interdependence has been established. ANNUAL ADDRESS OF THE PRESIDENT. LI It has thus been shown that there are three stages in the combina- tion of matter and motion, and that each stage is characterized by a clearly distinct method of evolution. These may be defined as follows : First, physical evolution is the result of direct adaptation to en- vironment, under the law that motion is in the direction of least resistance. Second, biotic evolution is the result of indirect adaptation to the environment by the survival of the fittest in the struggle for exis- tence. Third, anthropic evolution is the result of the exercise of human faculties in activities designed to increase happiness, and through which the environment is adapted to man. These may be briefly denominated: evolution by adaptation, evolution by survival of the fittest, and evolution by endeavor. Civilized men have always recognized to some extent the laws of human evolution,—that activities are teleologically developed, and that happiness is increased thereby. In the early history of man- kind the nature of teleologic endeavor was so strongly impressed upon the mind that the theory was carried far beyond the truth, so that all biotic function and physical motion were interpreted as teleologic activity. When this error was discovered, and the laws of physical and biotic evolution established, vast realms of phe- nomena were found to have been entirely misunderstood and falsely explained, and teleologic postulates have finally fallen into disrepute. Men say there is progress in the universe by reason of the very laws of nature, and we must let them alone. Thus, reaction from the ancient false philosophy of teleology has carried men beyond the truth, until they have lost faith in all human endeavor; and they teach the doctrine that man can do nothing for himself, that he owes what he is to physical and biotic agencies, and that his inter- ests are committed to powers over which he has no control. Such a philosophy is gradually gaining ground among thinkers and writers, and should it prevail to such an extent as to control the actions of mankind, modern civilization would lapse into a con- dition no whit superior to that of the millions of India, who for many centuries have been buried in the metaphysical speculations of the philosophy of ontology. When man loses faith in himself, and worships nature, and subjects himself to the government of the LII PHILOSOPHICAL SOCIETY OF WASHINGTON. laws of physical nature, he lapses into stagnation, where mental and moral miasm is bred. All that makes man superior to the beast is the result of his own endeavor to secure happiness. Man, so far as he is superior to the beast, is the master of his own destiny, and not the creature of the environment. He adapts the natural environment to his wants, and thus creates an environ- ment for himself. Thus it is that we do not discover a biotically aquatic variety of man, yet he dwells upon the sea and derives sustentation from the animals thereof by means of his arts. gA biotically arboreal variety of man is not discovered, but the forest are used in his arts and the fruits of the forests for his susten- tation. An aérial variety of man is not discovered, but he uses the winds to propel his machinery and to drive his sails; and, in- deed, he can ride upon the air with wings of his own invention. A boreal variety of man is not discovered, but he can dwell among the everlasting snows by providing architectural shelter, artificial warmth and bodily protection. Under the influences of the desert a few plants secure a constitu- tion by which the moisture imbibed during brief and intermittent rains is not evaporated; they become incrusted with a non-porous glaze, or contract themselves into the smallest space and exist with- out life until the rain comes again. Man lives in the desert by guiding a river thereon and fertilizing the sands with its waters, and the desert is covered with fields and gardens and homes. LEvery- where he rises superior to physical nature. The angry sea may not lash him with its waves, for on the billows he builds a palace, and journeys from land to land. When the storm rises it is signaled from afar,and he gathers his loved ones under the shelter of his home, and they listen to the melody of the rain upon the roof. When the winds of winter blow he kindles fossil sunshine on his hearth, and sings the song of the Ingleside. When night covers the earth with darkness he illumines his path with lightning light. For disease he discovers antidote, for pain nepenthe, and he gains health and long life by sanitation; and ever is he utilizing the materials of nature, and ever controlling its powers. By his arts, institutions, languages, and philosophies he has organized a new kingdom of matter, over which he rules. The beasts of the field, the birds of the air, the denizens of the waters, the winds, the waves, the rivers, the seas, the mountains, the valleys, are his subjects; the powers of nature are his servants, and the granite earth his throne. BULLEWIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON, GENERAL MEETING. BULLETIN OF THE GENERAL MEETING. 227TH MEETING. JANUARY 13, 18838. The President in the Chair. Twenty-six members present. Mr. H. FarquHar completed a communication begun at the 224th meeting on EXPERIMENTS IN BINARY ARITHMETIC, in which he showed that simple addition involved carrying on sev- eral distinct mental operations almost simultaneously and a capital of more than fifty propositions committed to memory. Believing that the difficulty in mastering, and the mental strain and liability to error in conducting, this most important of mathematical pro- cesses could be proved to be unnecessarily great, he had compared the time occupied in adding a few dozen numbers of six or eight figures each with that required when these numbers were expressed in powers of 2, the mental work being, in the latter case, reduced to counting similar marks and halving their sums. He had found it best to give different forms to the marks denoting neighboring powers, so as to avoid confusion of columns, and had combined two or more of them into one written figure for brevity of expression. About seventy combinations of various shapes had been tried, but very few of them found economical. In the best notation, however, the addi- tion required only three-fourths the time taken with the ordinary figures. Had the computer practised as many weeks with the new notation as years with the old, the difference would have been much more marked; as it was in fact when one unskilled in arithmetic, to whom the binary notation had just been taught, tried the two additions. The gain in accuracy, with this observer, was even 3 > 4 PHILOSOPHICAL SOCIETY OF WASHINGTON. more striking than the gain in speed. There could be very little doubt, therefore, that a fair degree of skill in arithmetic with a binary notation could be acquired by many to whom it is impossible under the present system. , The only practicable division of arcs and angles, and the most natural division of all things, is by continued bisections. This is shown by the ratio of value in our coins, weights, and capacity measures ; by any table of prices; and by the prevalent subdivision of lowest nominal units, as of the carpenter’s inch into eighths and sixteenths, and of percentages into quarters, etc., in stock quotations, where convenience of calculation by our present arithmetic seems almost gratuitously sacrificed. The American coinage is inconye- nient in practice, because of the awkward fractional ratio 22, which it introduces between successive pieces; and there would be the same difficulty in a decimal system of weights or of measures, should it be imposed upon us. We have thus another powerful reason for endeavoring to introduce a binary arithmetic. In the remarks which followed, Mr. E. B. E:uiorr expressed the hope that Congress would adopt the metric system of weights and measures for international purposes. It would be better to secure what advantage could be gained from uniformity and consistency, even though the basis of consistency was an arithmetic not ideally the best attainable. Such a course would not prevent, but might pave the way for a better arithmetic. Mr. W. B. Taytor said the world was losing so much by the employment of the denary arithmetic that he thought even a single generation might find economy in substituting the octonary. The introduction of decimal measures, while it would aid the computer, would injure the remainder of the community. The paper of Mr. Farquhar had an especial value, in that it proved the ability of binary systems to compete with the established system in rapidity of computation. Other remarks were made by Messrs. Harkness, Mussry, Pow- ELL, and GILBERT. The next communication was by Mr. 8. M. Burnert on REFRACTION IN THE PRINCIPAL MERIDIANS,OF A TRIAXIAL ELLIP- SOID; REGULAR ASTIGMATISM AND CYLINDRICAL LENSES ; and he was followed by Mr. W. Harkness on GENERAL MEETING. 5 THE MONOCHROMATIC ABERRATION OF THE HUMAN EYE IN APHAKTIA. These two papers are complementary, and are published in the Archives of Ophthalmology, Vol. XII, No. 1. 228TH MEETING. JANUARY 27, 1883. The President in the Chair. Thirty-seven members present. The Auditing Committee, appointed at the Annual Meeting, re- ported through its chairman, Mr. Antisell, that it had examined the accounts of the Treasurer for 1882, and found them correct. The report was accepted. The communication of the evening was by Mr. H. H. Bares on THE NATURE OF MATTER, and was discussed by Mr. W. B. Taytor and Mr. Powe tt. This paper is published in the Popular Science Monthly for April, 1883. 229TH MEETING. FEBRUARY 10, 1883. The President in the Chair. Forty-two members and visitors present. It was announced that reports of the scientific proceedings would hereafter be furnished to Science. Mr. W. H. Datu announced that an opportunity would be afforded members to contribute to the Balfour Memorial Fund. A communication was then read by Mr. A. F. A. Kine on THE PREVENTION OF MALARIAL DISEASES, ILLUSTRATING, inter alia, THE CONSERVATIVE FUNCTION OF AGUE. [Abstract. ] The various theories thus far presented in explanation of the - 6 PHILOSOPHICAL SOCIETY OF WASHINGTON. phenomena of malaria were unsatisfactory and insusceptible of scientific demonstration. ' According to the best medical authorities the most generally admitted facts upon which the present orthodox theory of malaria rests were as follows: 1. Malaria affects by preference low and moist localities. 2. It is almost never developed at a lower tem- perature than 60° F. 3. Its evolution or active agency is checked by a temperature of 32° F. 4. It is most abundant and most virulent as we approach the equator and the sea-coast. 5. It has an affinity for dense foliage, which has the power of accumu- lating it, when lying in the course of winds blowing from malarious localities. 6. Forests or even woods have the power of obstructing and preventing its transmission under these circumstances. 7. By atmospheric currents it is capable of being transported to consider- able distances—probably as far as five miles. 8. It may be devel- oped in previously healthy places by turning up of the soil, as in making excavations for the foundations of houses, tracks for rail- roads, and beds for canals. 9. In certain countries it seems to be attracted and absorbed by bodies of water lying in the course of such winds as waft it from the miasmatic source. 10. Experience alone can enable us to decide as to the presence or absence of malaria in any given locality. 11. In proportion as countries, previously malarious, are cleared up and thickly settled, periodical fevers disappear, in many instances to be replaced by typhoid fever (?) 12. Malaria usually keeps near the surface of the earth. It is said to “hug the ground,” or “love the ground.” 13. It is most dangerous when the sun is down, and seems almost inert during the day. 14. The danger of exposure after sunset is greatly increased by the person exposed sleeping in the night air. 15, Of all human races the white is most sensitive to marsh fevers, the black least so. 16. In malarial districts the use of fire, both in- doors and to those who sleep out, affords a comparative security against malarial disease. 17. The air of cities in some way renders the poison innocuous; for, though a malarial disease may be raging outside, it does not penetrate far into their interior. 18. Malarial diseases are most prevalent towards the latter part of summer and in the autumn. 19. Malaria is arrested not only by trees, but also by walls, fences, hills, rows of houses, canvas curtains, gauze veils, mosquito nets, and probably by fishing nets. 20. Malaria spares no age, but it affects infants much less frequently than adults. GENERAL MEETING. 7 These generally admitted facts were insusceptible of scientific explanation by the marsh fever hypothesis of Lanscisci; but were capable of explanation by the theory that marsh fevers are pro. duced by the bites of proboscidian insects, notably in this and in some other countries by mosquito bites. A review of the natural history, habits, and geographical distri- bution of the mosquito was next presented in explanation of the twenty statements above quoted. In discussing statement 15, it was maintained that the compara- tive immunity of the black races was largely due to color, the dark complexion of the skin being another illustrative instance of “ pro- tective coloring ” so often observed in other animals, and by which, in this instance, the negro was protected from the sight, and conse- quently from the dite of the mosquito; a similar protection being further secured by the offensive odor and greasiness of his cutaneous secretions, aided by artificial inunction of the body with grease, paint, pitch, &c., which last probably constituted the initial step in the evolution of dress. Hence malarial melanosis was considered to be the designed natural termination of ague—its conservative function—destined to modify the individual by defensive adaptation against the mosquito, whose penetrating proboscis, like an inoculat- ing needle, infected the body with malarial poison, no matter whether this last was mosquital saliva, the Bacillus malarie of Klebs and Crudelli, or some other element as yet unknown. The spleen, whose function is not yet settled by physiologists, was regarded as the chief pigment-forming organ, and was designed for this purpose in the economy of the organism. Generally con- sidered a superfluous organ, capable of removal without any great interference with the functions of the organism, it was naturally designed to meet the emergency of variation in skin-color to secure “ protective coloring ” against fever-producing proboscidian insects, as before indicated. The natural process, however, required expo- sure of the naked body to the sun during the chill stage, in order to secure deposit of the newly formed pigment in the skin. Nature had not anticipated the artificial appendage of dress, and the organ- ism had not inherited from ancestral progenitors any provision for so unexpected an addition. Chills do not occur at night, but only between the rise and setting of the sun; sunlight during the chill stage being a necessary requirement, in order that nature’s design of cutaneous chromatogenesis may be consummated. Other racial 8 PHILOSOPHICAL SOCIETY OF WASHINGTON. differences between the whites and blacks—such as even cerebral capacity and variations in the skeleton—might be susceptible of explanation by blood changes resulting from malaria. The marrow of bones was also a pigment-forming tissue, and the aching of bones during ague, especially in so-called “ break-bone” fever, suggested congestion and modified nutrition in the osseous structures, such as might eventually lead to modification in the skeleton. The inhabi- tants of oriental countries especially were more vigorous and intel- ligent if they lived in elevated regions, than were others inhabiting mosquito-infected lowlands and sea coasts. In further support of the mosquital origin of malarial fevers numerous noted medical authorities were cited, showing that, in all parts of the world where these diseases prevail, immunity was secured by protecting the body from mosquito bites. The geo- graphical distribution and seasonal evolution of mosquitoes and other proboscidian insects were shown partially to agree with the times and places in which malarial diseases prevail; though from lack of information conclusive evidence on this point was yet wanting. There was, however, a general admission on the part of medical authorities that swarms of these insects in almost any locality were a pretty sure sign of malignancy. On the other hand numerous instances were adduced from “ Nar- ratives”’ and “ Travels” in which the bodies of persons had been covered with pustules, “ resembling small-pox,” from mosquito bites without any subsequent occurrence of fever having been recorded by the narrating authors. This opposing evidence was inconclusive, (1) because the authors cited were not in search of medical information; (2) because the period of incubation, being often long and uncertain, fever may have occurred after the mosquito bites had been forgotten; (3) the insect proboscis (like a vaccine lancet unarmed with virus) might be uncontaminated with fever poison, or fever germs; and (A) successful inoculations of specific germ poisons are not usually followed by immediate local suppuration at the point of puncture, but only after a certain period of incubation, the immediate local inflammation being rather preventive of subsequent blood infection. The possible spread of yellow-fever contagion by the inoculating proboscis of the mosquito carrying infecting matter drawn from the blood of yellow-fever patients to unaffected persons was sug- gested. In epidemics, the spread of the disease stopped as soon as a freezing temperature paralyzed the mosquito, &c. ~ GENERAL MEETING. 9 The spread of spotted-fever, typhus-fever, in jails, ships, &c., was referred to the inoculating instrument of ‘fleas, &c.—these insects usually prevailing among filthy people thickly crowded together. That malarial diseases were ever produced solely by the inhala- tion of supposed poisonous vapors was held to be untenable. Ex- perimenters, who had demonstrated the existence of specific poisons for special fevers, had equally proven that the mode by which such poisons, when obtained, could be introduced into the body for the artificial production of disease, was by inoculation through the skin, These experiments were imitations of insect inoculation. The pro- boscis of the mosquito was Nature’s inoculating needle. The modus operandi of the eucalyptus tree in preventing malarial diseases was ascribed tentatively to the tree being destruetive to, or interfering directly or indirectly with, the propagation and develop- ment of mosquitoes. From the foregoing conceptions as to the origin of malarial dis- ease, the following prophylactic measures were deducible: 1st. Personal protection from all winged insects, especially during evening and night, by gauze curtains, veils, window-blinds, or clothing impenetrable by the proboscis of inoculating insects; and further, personal protection both from these and all creeping insects, especially during epidemics, endemics, and in crowded jails, ships, &c., by daily inunction of the whole body with some terebinthinate, camphorated, or eucalyptalized ointment or liniment. 2d. Domiciliary protection (a) exteriorly, by screens of trees, walls, fences, &c., interposed at some distance between dwellings and the supposed sources of malaria, or mosquito nurseries ; and with fires or lamps arranged as traps for the attraction and destruction of such winged insects as may encroach nearer. A further protection (6) in the interior of dwellings being secured by the use of smoke (as of tobacco or prethrum) or of some volatile aromatic substance, as of camphor, assafcetida, garlic, &c., which may be offensive to proboscidian intruders. 3. Municipal protection by groves of trees (pines, cedars, or eucal- yptus) planted between cities and the sources of malaria and mos- quitoes, together with cordons of electric or other lights, between said grove and the marsh, the lights to be arranged as fly-traps for the retention and destruction of such winged insects as may be thus secured. 5 > 10 PHILOSOPHICAL SOCIETY OF WASHINGTON, With relation to the city of Washington, it was suggested that the Washington monument would afford a good opportunity (by placing illuminated fly-traps at different elevations on its exterior) for ascertaining the height at which mosquitoes fly, or are brought by the wind from the adjacent Potomac flats. The proposed re- clamation of the flats could scarcely do more than mitigate malarial disease, so long as our summer and autumn southern breezes come, laden with mosquitoes, from the miles of unreclaimed swamps farther down the river, as at Four-mile Run and other nearer local- ities. Mr. Bruuincs remarked that, since ague did not invariably result from insect bites, the most that could be claimed was that they accomplished an accidental inoculation with malarial poison. The subject was also discussed by Messrs. DoouirrLe, ToNER, and ANTISELL. The meeting closed with an exhibition by Mr. C. E. Durron of a series of oil paintings illustrative of the Hawaiian Islands. 230TH MEETING. Fresruary 24, 1883. Vice-President Briiines in the Chair. Thirty members and visitors present. The Chair announced the election of Mr. Taomas RussELtL to membership. The first communication was by Mr. G. K. GitBErt on THE RESPONSE OF TERRESTRIAL CLIMATE TO SECULAR VARIATIONS IN SOLAR RADIATION. [ Abstract. ] Secular variations of climate may theoretically be catised (1) by the internal heat of the earth and (2) by changes in the constitu- tion or volume of the atmosphere. They have unquestionably been wrought (3) by changes in the limits and configuration of ocean bottoms and land surfaces, (4) by changes in the movements of the earth with reference to celestial bodies, and (5) by variations of GENERAL MEETING. ng solar radiation. Attention will here be restricted to the last-men- tioned cause. An augmentation of the strength of solar radiation (a) will cause a general rise in the temperature of the atmosphere, (0) will heighten the contrast between warm and cold regions, thereby stimulating oceanic and atmospheric circulation, and (ce) will heighten the con- trast between wet and dry regions, making the wet wetter and the dry drier. (d) It will also diminish glaciation. This has been dis- puted by some writers, but is sustained by a quantitative discussion. A computation, based on the annual curves of precipitation and tem- perature at St. Bernard, close to the glaciers of the Alps, shows that a general rise in the temperature of the air, while it will increase the total precipitation, will slightly diminish the snow-fall ; that it will very greatly increase the rate of melting. The ratio of snow-fall to evaporation is reduced one-half by 6° C rise of temperature ; the ratio of snow-fall to melting is reduced one-half by a rise of 13°; and, assuming that evaporation actually dissipates twice as much snow as does melting, the ratio of snow-fall to snow dissipa- tion (or the tendency to glaciation) is reduced one-half by 42° rise of temperature.* (e) Increase of solar radiation will also, through its general effects, influence the distribution of winds, and thus produce sec- ondary effects of a local nature. Mr. Dawu remarked that ice was rendered more plastic and fluent by the presence of water; so that the movement of ice and the consequent. extent of glaciers are favored by rain. If Mr. Gilbert by the term “ glaciation” referred to the extent of glaciers, some limitation of his conclusions might be necessary. Other remarks were made by Messrs. ANTISELL, DooxiTrLe, H. FarquuHar, and Exv.iort. The next communication was by Mr. J. W. CHIcKERING on THE THERMAL BELTS OF NORTH CAROLINA. [ Abstract. ] In the agricultural volume of the Patent Office Report for 1861 is an article written by Mr. Silas McDowell, of Franklin, Macon county, N. C., bearing this title. He was a man of much intelli- * The computation is given in full in “ Science’’ for March 16, 1883. 19 PHILOSOPHICAL SOCIETY OF WASHINGTON. gence, an enthusiastic student in geology and botany, a companion and guide of several botanists in their early explorations of the southern Appalachians, and a farmer by profession. He died in 1882, at the ripe old age of 87. He states that in the valley of the Little Tennessee river, in Macon county, lying about 2,000 feet above tide water, when the thermometer in the morning indicates a temperature of about 26°, the frost line extends about 300 feet in vertical height, but that then comes a belt extending about 400 feet in vertical height up the mountain side, within which no frost is seen, delicate plants remain- ing untouched. Above this, frost again appears. So sharp is the dividing line that sometimes one-half of a shrub may be frost killed, while the other half is unaffected. A small river, having its source in a high plateau 1,900 feet above this, runs down into this valley, breaking through three mountain barriers, and consequently making three short valleys, including the plateau, rising one above the other, each of which has its own vernal zone, traversing the hillsides that enclose it, and each beginning at a lesser elevation above the valley, as the valleys mount higher in the atmosphere, so that around the plateau, a beautiful level height, containing 6,000 acres of land, aud lying 3,900 feet above tide water, the lower edge of the thermal belt is not more than 100 feet above the common level of the plateau. Not only does vegetation within this zone remain untouched by frost, so that the Isabella, the most tender of all the native grapes, has not failed to produce abundant crops in twenty-six consecutive years, but mildew, blight, and rust, which often attack vines in the lower valleys, are here unknown, while the same purity and dry- ness of the air which favor the grape, make this a refuge for the consumptive, as diseases of the lungs have never been known to originate among the inhabitants. Mr. McDowell adds: “The thermal belt must exist in all coun- tries that are traversed by high mountains and deep valleys, and the only reason why its visible manifestations are peculiar to our southern Alleghanies, is the fact that their precocious spring vegeta- tion is sometimes killed by frost, while the same thing does not happen in the mountains further north.” These statements are corroborated by similar testimony respect- ing another such belt along the Tryon mountain range in Polk county, N. C.; the specific claim being that such a belt is found GENERAL MEETING. eo for eight miles in length, extending from 1,200 feet to 2,200 feet above tide water, within which the leaves of plants, shrubs, and flowers remain untouched by frost until the latter part of Decem- ber, and after a snow storm not a particle of snow remains within the belt, while the tops and sides of the mountains above and the valleys below will be covered. The verification of these alleged facts would be matters of interest in their economical and sanitary aspects, and would supply data for some interesting researches respecting the nocturnal stratifica- tion of the atmosphere. It is earnestly to be hoped that at some time we may have reli- able and continuous thermometrical observations at these and simi- lar stations, to determine the existence, extent, and temperature of such belts. Remarks were made on this communication by Mr. ALvorD. Mr. C. E. Dutron then made a communication on the GEOLOGY OF THE HAWAIIAN ISLANDS. [ Abstract. ] On the slopes of Mauna Loa are sea beaches, terraces, coral sands, and other evidences of shore action at various levels. The highest that can be positively announced has an altitude of 2,800 feet above the ocean. It can be traced a large part of the way around the island, being discernible even when covered by more recent lava. It does not now lie horizontal, but descends from 2,800 to 400 feet, while on the adjoining island, Maui, there is evidence of submergence. On the farther (western) side of Maui, and on other islands beyond, there is again evidence of upheaval. All the lavas of the islands are basaltic. Those of Mauna Loa and Kilauea are abnormally basic and are related to certain lavas of New Zealand, called by Mr. Judd “ ultra-basalts.” ‘The New Zealand rock consists chiefly of olivine; that of Mauna Loa is sometimes more than half olivine, and contains much magnetite and hematite. A Greenland lava, classed also as ultra-basalt, contains the only known native iron of telluric origin. As this suggests the iron meteorites, so the basalts of New Zealand and Mauna Loa suggest the stony meteorites. The volume of the eruptions of Mauna Loa is enormous; that of 1855 would nearly build Vesuvius, and two of prehistoric date > 14 PHILUSOPHICAL SOCIETY OF WASHINGTON. were greater still. The lava has a high liquidity and flows forty to fifty-five miles, spreading at the base of the cone into a broad sheet. There are no explosive phenomena and no fragmental pro- ducts. The slope of the mountain is 4° along the major and 7° along the minor axis. Kilauea has a few cinder cones on its flanks. -Mauna Kea consists chiefly of them, and has an average slope of #4° 011°. Kilauea is always active, maintaining lakes of liquid fire.’ Over one of these a crust is formed, black, but flexible, which after a while breaks up and suddenly sinks, the process being repeated at intervals of 14 to 2+ hours. The great interior pit described by observers from 1823 to 1841 is now filled. Mauna Loa is not active more than one-third or one-fourth of the time, but compensates by the magnificence of its phenomena. Great fountains of lava are projected hundreds of feet into the air. Mr. Dutton’s communication was interrupted by the arrival of the hour for adjournment. In response to a question by Mr. Tay- LOR, he stated that the crust over a lava lake acquired a thickness of five or six inches before breaking up. Mr. ANTISELL inquired whether there is any basalt on the islands, and Mr. Dutton explained that they are composed exclu- sively of that material. 231st MEETING. Marcx 10, 1883, Vice-President WELLING in the Chair. Thirty-four members and visitors present. The Chair announced that Messrs. ALBERT WILLIAMS, Jr., JoHn Henry ReEnNsHAWE, and Henry Francis Wauuine had been elected to membership. Mr. M. H. Doo.irt_e read a communication on SUBSTANCE, MATTER, MOTION, AND FORCE, which was discussed by Messrs. W. B. Tayitor, Evtiorr, HarK- NEss, and WELLING. Mr. E. B. ELLIoTr then communicated GENERAL MEETING. 15 FORMULAS FOR THE COMPUTATION OF EASTER. In the calendar the vernal equinox is considered as invariably occurring on the 21st of March. The Paschal full moon is the full moon which (according to the calendar) occurs on or first after the 21st of March. Easter Sunday in any year is the first Sunday which occurs after the Paschal full moon; that is, first after the full moon which, according to the calendar, occurs on or first after March 21st. To find the date of Easter Sunday for any year, A. D., New Style. Let ¢ denote the complete hundreds of years in the number de- noting any year, and y the number of remaining years. Thus in the year 1883, c = 18 and y = 83, the number for the entire year, 18838, being denoted by 100 ¢ + y. In the following formulas w, as a subscript after a division, de- notes that only the whole number of the quotient is to be retained, and r,as a subscript, denotes that only the remainder after the division. is to be retained; thus( 7) =4: and (=) we 4 Ww 4 r nm (the golden number Jess one) = (8), = Ct), = C9, = GYD, =n LCs), + (i), J, This number (7) pertains to a lunar cycle of 19 years. 8 a” = (4) s=é—8— (4) -(‘# 25 Ww iy 3 Ww Inspection of the formula for s will show that, for any year from 1700 A. D. New Style to 1899 A. D., both inclusive, the value of sis zero (0). For any year Old Style the value of s is the con- stant number 22. - 23 q= (a ma = =) ; also, r 23 +s—11 *) I Pa WwW = > 16 PHILOSOPHICAL SOCIETY OF WASHINGTON. The value of A may be shown to be zero (0) for any year from 1700 A. D. to 1899 A. D., both inclusive, during New Style, and for all years during Old Style. p =q—h=the interval in days from March 21st to the date of the Paschal full moon, or the number of days to be added to March 21st to find the date of the Paschal full moon. If p = zero (0), the Paschal full moon accordingly falls on the 21st of March. n—(1+2(5),-1-(G),+ Go). ) ZL denotes the number (in alphabetical order) of the Dominical or Sunday letter. Thus, the number corresponding to the Domini- cal letter A is 1, to B is 2, to C is 3, to D is 4, to E is 5, to F is 6, and to G is 7 or 0 (zero). c ; ; , The term (a5) gives a correction to the Gregorian value when Ww the year exceeds 4000 A. D.; for any year less than 4000 the value of this corrective term is obviously zero (0). (? ae rime 3+6p+L a ee 7 r 7 r t denotes the number of days which elapse after the date of the Paschal full moon to the date of Easter Sunday. Easter Sunday = March (21 +1+p+#—1) = March (21 + p + 2) == April (p+t— 10) To find the date of Easter Sunday for any year, A. D., Old Style. aif Feat c.f 100g = 2) eae ( ie a9 ( r 19 19 The formula for n is the same as in New Style. (Gee ae = (ets (ae q=p= 2 ), =), = Ee Gascon 5 7 ys pain (C=HEY), = (EYP) rE GENERAL MEETING. 17 Faster Sunday = March (21 +1+p+t—1) = March (21+ p-+ 2) = April (p+t—10) ° Exampte 1.—Required the day of the month on which Easter Sunday falls in the year 1883 A. D., New Style. ( a “) = (73), i, (45), (=) J dter = 1: 5 (5) Eonar 25 r 1 19 19 exes, 197, 19 oe n=—5+7=2 20 n = 40 19» = 20n—n= 88 ae et == die 3 =10-4—(=;~) =10-4-6=0 23+8s+19n (23 + 0+ 38 q= ( jhe ea 30 = 30 | ie (35), + i9—1 (), (),=0+28x0x0=0+40=0 p=q—h=1—-0=1 2G), aoa (a). ) ny ( = (a) _ Ge 84) a0 ‘Easter Sunday = March (21+1+p+t—1) = March (22 + 1 + 2) = March 25 18 PHILOSOPHICAL SOCIETY OF WASHINGTON. Examp_e 2.—Required the date of Easter Sunday for the year 1884 A. D., New Style. 20 n = 60 20 —n=19n =)57 a ie 23+0+57\ | a= ( 30 ), =20 20 20 3 n= (5), —™ (38), (7a), =0+9x0x0=0+4+0=0 p=q—h=20—0=—20 z—( 1+? Cie ae: (a). ) it SS fe 704-5 a 35 Ms: im1- (74>) = (4°), =2 Easter Sunday = March (21 + 1+ 20 + 2) = March 44 = April (44 — 31) = April 13 EXAMPLE 3.—Required date of Easter Sunday for the year 3966 A. D., New Style. 39 | 66 2x 19 = 38] 57 = 3x19 : ile Bey _ (SX1+9 n= ( 19 Ha 19 ) =u 20 n = 280 19 n = 20n — n= 266 GENERAL MEETING. 19 Peco ase (=) - ( Pe ae (“3 J.) 3 = s1—9—(">*) Sage oo 13 19 Ww at (tet =") = (2+ = “\ = 28 28 ee ER 14 =h (55), + 2 — 28 (55), cae =04+1x*1x1=04+1=1 p=q—h=28—-1=27 z-(1+2(@), "= (9). @).) 7 14+2x38—3—2+0 3—pt+L 3—27+2 Easter Sunday = March (21 + 1 + 27 + 6) = March 55 = April (55 — 31 =) 24 EXAMPLE 4.—Required the date of the Paschal full moon (March 21+ p), and the date of Easter Sunday (March 21 + p +t or March 21 + 1+ p+ (¢—1) for the year 2152 A. D., New Style. 2152 ; (Fx), =5=" Poe 95 <— a 23= 23 —— 19+ s+ 23 = 119 r= (M*%) = (9) ao h=1+0X0X0= 1 p= q—h= 28 > 20 PHILOSOPHICAL SOCIETY OF WASHINGTON. Paschal full moon = March (21 + 28 =) 49 == April (49 — 31 =) 18 Le -( +2(3), is ae (a). ) = = (2H ¢=I= 8) G2) ot 7 ESE eh (——') | ir Easter Sunday = March (21 -+1-+ 28+4 =) 54 = April (64 — 31 =) 23 The Julian or Old Style Calendar was established by the Council of Nice A. D. 325; the first year of the Gregorian or reformed calendar was A. D. 1582, and the first year in which the reformed calendar was adopted in England was A. D. 1752. In Russia, and in other countries where the religion of the Greek Church now obtains, the New Style of reckoning has not been adopted, but the Old Style is still in force. In Alaska, Old Style was employed until after the cession of that country by Russia to the United States in the year 1869. EXAMPLE 5.—Find the date of Easter Sunday for the year 1582 A. D., Old Style. 15 |\ 682 5 +15 | =75 90—1) 157.° @ 101 “AT +7=24=19+45 m= 5 19n = (20—1)n=100—5 = 95 =3 %30 +5 _ (19m4+15) (5415) _ - a= ( ee el 30), = 20 p-(4e =) x (H=7=*) = = (77) =0 GENERAL MEETING. 21 2 Easter Sunday = March (22 + 20+ 4=) 46 == April (46 — 31 =) 15 232p MEETING. Marca 24, 1883. Vice-President WELLING in the Chair. Forty-three members and visitors present. The first communication was by Mr. J. R. Eastman on THE FLORIDA EXPEDITION FOR OBSERVATION OF THE TRANSIT OF VENUS. [ Abstract. ] The observing station of the Florida expedition was upon Way Key, the largest of the group of islands known as Cedar Keys. The principal instruments employed were a portable transit, a five-inch equatorial telescope, and a photoheliograph. The first two require no description. The photoheliograph consisted of an objective of five inches aperture and about forty feet focus, a helio- stat for throwing the sun’s rays on the objective, and a plate holder at the focus of the objective. The accessory apparatus consisted of a measuring rod, permanently mounted, for accurately measuring the distance from the objective to the photograph plate; a movable slide with a slit of adjustable width, for exposing the plates; and a - circuit connecting with a chronograph, so arranged that when the exposing slide was moved to expose the plate, and when the center of the slit was opposite the center of the plate-holder, the circuit was broken and the record made on the chronograph. A black disk was painted on one side of the slide, and so placed that when the slide was at rest at one end of its course and the image of the sun was adjusted concentric with this disk, it would fall on the center of the plate-holder when the slide was moved. The adjust- ments having been completed the exposing of the plates was a sim- ple matter. The image of the sun was thrown by the heliostat upon the black disk and centered, the sensitive plate was fixed in > 22 PHILOSOPHICAL SOCIETY OF WASHINGTON. the plate-holder, the operator moved the exposing slide, and the time of exposure was recorded on the chronograph. For observing contacts I used an eye piece, magnifying 216 diam- eters, attached to a Herschel solar prism, and a sliding shade-glass with a density varying uniformly from end to end. The time of my signals was taken by assistant astronomer Lieut. J. A. Norris, U.S. N., from a chronometer; while, with an observing key, I also made a record on the chronograph as a check. About 40 seconds before the computed time of first contact a narrow stratus cloud passed on to the southeastern edge of the sun and shut out all the light. The cloud remained about 3 minutes, and when it passed off, the notch in the sun’s limb was plainly marked. Two photographs were taken to test the apparatus and the plates, and then the time before second contact was devoted to an examination of the limbs of Venus and the sun. Both were perfectly steady. In observations of the sun for the last twenty years I never saw it better. At about 13 minutes after first contact the outline of the entire disk of Venus could be seen, and seemed perfectly circular. About 2 minutes later a faint, thin rim of yellowish light appeared around the limb yet outside the sun. This rim was at first broadest near the sun’s limb, but soon the width of the light became uniform throughout. The light was wholly ex- terior to the limb of Venus; that is, the black limb of Venus on the sun and the dark limb outside formed a perfectly circular disk, with the rim of light or halo, outside the portion off the sun. As the time of second contact approached, Lieutenant Norris again took up his station at the chronometer. As the limbs neared geo- metrical contact, the cusps of sunlight began to close around Venus more rapidly; and the perfect definition of the limbs and the steady, deliberate, but uniformly increasing motion of the cusps, convinced me instantly that the phenomena attending the contact would be far more simple than I had ever imagined. I had only to look steadily to see the cusps steadily but rapidly extend themselves into the thinnest visible thread of light around the following limb of Venus and remain there without a tremor or pulsatiom At the moment the cusps joined I gave the signal and also made the record on the chronograph. Still keeping my eye at the telescope, I saw nothing to note save the gradually increasing line of light between the limbs of the two bodies. The disk of Venus on the sun was black. GENERAL MEETING. 23 A re-examination was then made of all the photographic appara- tus, and about 10 minutes after the second contact the principal photographic work was commenced; and this was continued with slight interruption until about 10 minutes before third contact ; 150 dry plates and 30 wet ones being exposed. One of the inter- ruptions was for the purpose of making measurements of the diameter of Venus, which was done with a double-image micrometer attached to the 5-inch telescope. ; On going to the telescope to observe the last contacts, I found the limbs of Venus and the sun as steady as in the morning, and though there was now some haze over the sun it did no harm. The third contact was observed with great accuracy, nothing occurring to obstruct or complicate the very simple and definite phenomena, which were in the reverse order of those seen at second contact. The rim of light appeared around Venus as soon as the limb was visible beyond the sun, and was seen for nearly 10 minutes. The complete outline of Venus was visible for 2 minutes longer. No phenomena worthy of note were seen between third and fourth con- tacts. The lapping of the limb of Venus over that of the sun gradually but steadily decreased until the final separation, which was observed with great accuracy for such a phenomenon. Soon after the last contact the entire apparatus was again carefully examined and the necessary observations made to determine the errors of the chronometers. In the observations of interior contacts there was no trace of any tremor or fluctuation of the light in the cusps as they closed around the limb of Venus; and it is almost needless to say that there was no trace of a shadow or a black drop or ligament between the limbs at second and third contacts. The probable error for the second and third contacts was estimated at 0”.3; for fourth con- tact, 0’.5. Observers of transits of Venus and Mercury have written so much in regard to the obstacles encountered from the apparition of the shadow, or black drop, between the limbs of the two bodies at second and third contacts, and so full has been the testimony in favor of the existence and the almost necessary occurrence of this phenomenon, that at the transit of Mercury, in 1878, many ob- servers claimed, as evidence of their skill, that they did see it; while others, less fortunate, apologized for not seeing it. Observers of the black drop were so generally confined to those with imperfect > 24 PHILOSOPHICAL SOCIETY OF WASHINGTON. apparatus or to those unaccustomed to observation of the sun’s limb or disk that the true nature of the obstacle was pretty well understood before it was carefully investigated. It is now quite well settled that the “black drop” is due to bad eyes, imperfect apparatus, or the inexperience of the observer. With good eyes and proper apparatus a good observer never should see the black drop. When it is seen there is something wrong; it is a spurious phenomenon. _ One of the negatives was exhibited to the Society. In reply to a question by Mr. E. J. Farquaar, Mr. Eastman said the halo about Venus was believed to be due to the atmosphere of the planet. The next communication was by Mr. CLEVELAND ABBE on DETERMINING THE TEMPERATURE OF THE AIR. He stated that the question now to be considered is not where to place a thermometer so as to obtain the temperature most proper for the use of the meteorologist, but is rather the purely physical question of how to determine the temperature of the air at any given location. He described the methods and defects of the for- mer and present meteorological methods of exposure, viz: (1) Ther- mometers hung in the open air. (2) Those’ placed in shady loca- tions. (3) The Glaisher screen. (4) The Stevenson screen and the double louvre screens in general. (5) The double metallié cylin- drical shelters of Jelinek and Wild. (6) The silver thimble screen of Regnault. (7) The whirling thermometer of Saussure, Arago, Bravais, and the French observers (exhibiting Babinet’s arrange- ment as made by Casella.) (8) Joule’s method, depending on a balance in the temperature and density of two columns of the air. He then gave a description of the method devised by him in 1865 and used for a short time at Poulkova; this consisted in con- structing a very perfect louvre screen, within which were established black bulb and bright or silvered bulb thermometers having very diverse coefficients of radiation and conduction. These thermom- eters were in air, not in vacuo, as this latter arrangement was proper only for the determination of the direct solar radiation, as in the Arago-Davy method, whereas in the present case the temperature of the air and the radiation from terrestrial objects were the special objects of study. GENERAL MEETING. 25 The air temperature (t,) was found from the indications of the bright and black bulbs (t, and t,) by the empirical formula t= t, + C (tr —t) where C is a small coefficient, to be determined experimentally, and is nearly constant. This arrangement of bright and black bulbs can be used by meteorologists and physicists without a screen, and even in the sunlight, if the theory of the action of the bright and black bulbs is perfectly understood. A similar for- mula will give the temperature (T) of a single radiating body whose effect is equal to the total effect that is shown by the black bulb: T=t,+C (,—t..) He then stated that the theoretical basis of this method has quite recently been further elucidated by Professor Ferrel, who has shown that the approximate nature of the relation between the above con- stant C, the radiating, absorbing, and conducting powers of the _thermometers, and the velocity of the wind is given by the following equation : Br, 1+ = pr B’/+B ae eT y p Dea 1 where r, and r, are the radiating (and absorbing) powers of the blackened and silvered bulbs, respectively, v is the velocity of the wind or currents flowing past the bulbs, and B B’ B” are constant coefficients depending on the size, conductivity, and specific heat of the substance of the bulbs. In reply to a question of Mr. GiLBert, he stated that the differ- ence between the bright and black bulbs had rarely exceeded a few tenths of a degree in the delicate shelter made of oiled paper, as used by him at Poulkova, the maximum occurring February 22, 1866, at 10 a. m., when, the louvre box being in the full sunshine, the bright bulb was at 14°.9 Cent. and the black bulb at 14°.3, showing that the latter had been slightly warmed by the warm sides of the box. In reply to a question of Mr. Harxness, the author explained, that although it was conducive to accuracy that these thermometers should be placed within a shelter, yet this was not necessary; if we take advantage of the more accurate method of determining 6 ~ 26 PHILOSOPHICAL SOCIETY OF WASHINGTON. the co-efficient constant C, as given by Prof. Ferrel’s theory, the two thermometers placed anywhere within doors or without would still give data for determining temperatures of the loca- tion; it should be borne in mind that the temperature thus ob- tained belongs specifically to the air in contact with the themome- ters and is not an average value for any extensive portion of the atmosphere. As it is an advantage to conduct observations under uniform conditions, it is recommended that a pair of bright and black bulb thermometers be attached to the whirling table, whereby the effect of a current of air may be on the one hand determined and on the other hand kept as ‘uniform as possible. Mr. Harxness said that the object practically sought by meteo- rologists was to learn the average temperature of a considerable body of air, but their efforts were thwarted by the irregularity and inconstancy of the distribution of temperature. So long as the air in contact with the thermometer is not precisely representative of the air of the vicinage it was useless to refine methods of observa- tion, unless by that refinement errors of a constant nature were eliminated. For the determination of mean monthly or annual temperatures he considered the reading of the nearest half degree as sufficient, and regarded the reading of the tenths of a degree as a useless refinement. . The advantage of reading to tenths was further discussed by Messrs. ABBE, DooxirrLeE, and Kummetyt. Mr. KumMMeE.y pointed out that where a difference of temperature is observed as an indication of the moisture of the air, the tenths are worthy of record. The following communication by Prof. Coartes E. Munrog, of Annapolis, Md., was then read by the Secretary : DETERMINATION OF THE SPECIFIC GRAVITY OF SOLIDS BY THE COMMON HYDROMETER. Having occasion some time since to devise methods for the ex- amination of coal on board ship, I was obliged, as my first con- sideration, to work with such materials and apparatus as are usually found in ships’ stores, and then to arrange the methods so that they could be used under the restricted conditions which prevail. The unsteadiness of the ship makes balance methods for the determina- tion of specific gravities difficult, even when a suitable balance is at GENERAL MEETING. 27 hand, while hydrometers may be steadied so that the instrument may be read with a reasonable degree of precision, as is shown in its constant use in the determination of the degree of saturation of the water in the steam-boiler, and in other instances. To use the hydrometer for the determination’ of the specific gravities of solids I take advantage of the fact that, when a body floats in a liquid in which it is wholly immersed, the specific gravi- ties of the liquid and the solid are the same, and we have simply to determine the value for one of them. The process is carried out by taking a dense solution, dropping in it the solid to be determined, (which must be light enough to float on the surface,) and then diluting slowly with water until the solid floats immersed, stirring the mixture constantly. The solid is now removed and the hydrometer inserted and read. For the determination of the specific gravities of the bituminous coals and lignites a thick solution of cane sugar was used, while for the heavier anthracite concentrated sulphuric acid, diluted with dilute sulphuric acid, was employed. The increase in temperature in the latter case causes no appreciable error if the reading is quickly taken. The following results were obtained by the method des- cribed, the specific gravity of each specimen having first been de- termined by Jolly’s balance: By Jolly’s balance. By mixture. PTI LOLA CLE Mots sure eee eS 1.5640 1,560 Bituminous ‘coal’ 22 bs 2 pat eureh 1,3008 1,310 Bituminous) coals sxe) (yee woes 153000 1,300 (AIS (CIDE ne SIS oa AE ne 1,2790 1,285 Canney coala@ipniform) 222-2 ==. 22 b 1,1550 1,155 Cannelicoali acest eee ie el a 1,1292 1,120 VRSp SES) Leela — 1,0909 1,090 Mr. Durron remarked that the same principle had recently been successfully applied to the separation of the component minerals of crystalline rocks. A sample is powdered and then placed in a very heavy liquid (a solution of mercuric iodide and potassium iodide), the density of which is gradually diminished, until the particles of the heaviest mineral sink to the bottom. A repetition of the process eliminates each mineral in turn. 28 PHILOSOPHICAL SOCIETY OF WASHINGTON. 233p MEETING. ApRIL 7, 1883. Mr. Wa. H. Datu in the Chair. Thirty-six members and visitors present. The Chair announced that Messrs. EnwARD SANDFORD BURGESS and SUMNER Homer BoprisH had been elected members. The General Committee reported to the Society that “a Mathe- matical Section had been organized by the election of Mr. AsaPH HA. as Chairman and Mr. Henry Farquuar as Secretary. All members of the Society who are interested in mathematics are in- vited to attend and take part in its meetings, announcements of which will be sent to those who notify the Secretary of a desire for them.” The first communication was by Prof. W. C. Kerr on THE GEOLOGY OF HATTERAS AND THE NEIGHBORING COAST. [ Abstract. ] The notable projection of Hatteras, beyond the general line of trend of the Atlantic coast, has, of course, a geological origin. The study of the changes now taking place, and of the phenomena which have left their recent traces on the surface, readily furnish the data for the solution of the problem. Nearly one-half of this eastern inter-sound region of North Carolina is water surface, and the land surface lies for the most part below ten feet (much of it below five.) A large part of this low-lying surface is covered with beds of peat, which thicken towards the centre on the divides or swells be- tween the bays and sounds, rising, in some cases, to ten and fifteen feet, and in the Dismal Swamp on the northern border of the State to twenty-two feet. These beds of peat are in process of forming by the decay of plants growing on the surface, chiefly cypress and juniper. Many tiers of the undecayed logs of these timbers are piled upon one another through the whole thickness of the deposit, which is soft and yielding, so that a fence-rail may be thrust down beyond its length. Vast tracts of such peat swamps (and of marsh and savanna on which only water grasses and small shrubs and scrub pines grow and decay) are found throughout this coast region. Here we have the first stage in the formation of a coal bed. Another notable fact is that many of the rivers which empty into the sounds GENERAL MEETING. 29 increase in depth of channel at a distance from their mouths; while the sounds are 12 to 15 and 20 to 22 feet deep, the rivers are often 30 and 40 feet and upwards. This can only be accounted for by supposing a subsidence of the region to be in progress, the sounds and open bays being silted up by the deposits brought down by the floods of the Roanoake and other large rivers, while no particle of sediment can reach the sheltered depths of the narrow windings of the upper reaches of these minor streams. This theory of subsidence is abundantly confirmed by the disappearance under water of large tracts of swamp bordering the rivers, as the Chowan, within the observation of men now living, and by the existence of rooted stumps of cypress and juniper in the bottom of the bays and sounds, even to the depth of 15 and 20 feet, and also by the vertical and crumbling shores of the sounds, undermined and eroded by the advancing waves. The Atlantic ocean is walled off from this region by a narrow fringe of sand islands, or dunes, blown shoreward by the wind and thrown up into reefs and hillocks like snow-drifts 50, 80, and even more than 100 feet high. The movement of these sand.waves being inland, the sounds are silting up next the sea, and are in many places converted into marshes 3 to 5 miles wide. The reef is increasing in continuity and breadth, most of the inlets above Hat- teras that were open 300 years ago being closed and obliterated. An inspection of the form of the curves of the submarine contours off Hatteras and adjoining coasts will show that the action of the tides and ocean currents, the Gulf stream and Arctic current meet- ing at this point, accumulate upon Hatteras the river silt which reaches the sea by way of the Chesapeake as well as that of the rivers which discharge their burdens through the inlets about this point and southwards. Which amounts to this—that Hatteras may be described as a sort of delta, whose materials are derived from the drainage of more than 100,000 square miles of the Atlantic slope. A subsidence of about 20 feet would bring the sea again over the entire Sound region and carry the shore 75 miles inland, bringing Hatteras to coincide with Cape Lookout. A sand reef, like that north of Hatteras, marks the line of the ancient shore, when these conditions obtained. A depression of fifty feet would move the shore 100 miles west of Hatteras and carry the point of meeting of the conflicting ocean currents and waves to Cape Fear. A subsidence of 500 feet, as in the glacial period, would carry 30 PHILOSOPHICAL SOCIETY OF WASHINGTON. Hatteras more than 200 miles west of its present position. This horizon is marked by an immense sand reef, still retaining its wind and wave marks, and rising to a height of more than 500 feet above tide, the reef itself being at least 100 feet deep and many miles in length. The sea must have remained at this level for a very long period. But Hatteras is not a modern phenomenon. It is at least as old as the cretaceous; the quaternary as well as the tertiary of this coast region of North Carolina are laid down upon an eroded surface of cretaceous rock, while the artesian borings, at Charleston, reach this formation at 700 feet, and at the mouth of the Chesa- peake they do not seem to have touched it at 1,000 feet. Mr. Warp remarked that, in traversing the Jericho canal of the Dismal Swamp in a row boat, he had observed an outward flow at both ends of the canal, showing that, by continuous water passage, a divide was crossed between Lake Drummond and the James river. He criticised the doctrine taught in text-books and popular writ- ings that the preservation of leaves in a fossil state is due ordinarily to river action and delta formation. More favorable conditions are to be found in swamps. Other remarks were made by Messrs. Durron and Hove. The second communication was by Mr. H. F. Waiine on TOPOGRAPHICAL INDICATIONS OF A FAULT NEAR HARPER'S FERRY. [ Abstract. ] A description was given of a break in the continuity of the Blue Ridge, where its disconnected portions, extending side by side for a few miles, are cut by the Potomac river, near Harper’s Ferry, the gorges so formed presenting a striking feature of the scenery. The two ridges, here about 12,000 feet apart, stretch for hundreds of miles in nearly parallel directions, one to the south and the other to the north; the latter being known in Pennsylvania as the South Mountain. ‘The strike of the rocks is parallel to the ridges, about N. 30° E., and the prevailing dip is eastward; averaging not more than 30°. The ridges are composed of hard sand-rock; the adjacent region, of lime-stone and other, rocks more easily dis- integrated or dissolved. Supposing the sand-rock of the Blue Ridge and South Mountains to have been originally a continuous formation, it will be readily GENERAL MEETING. 31 seen that a vertical fault in easterly dipping strata, having its direction somewhat nearer the meridian than the present strike and its downthrow on the west side of the fault, would produce a lateral discontinuity like that here observed, the upthrown part of any stratum cropping out on the east of the downthrown part at a distance depending upon the amount of the vertical displacement. All this would depend upon whether the sand rocks were origi- nally continuous in the two ridges—a question which was left for the geologists to decide. The writer, however, took occasion to suggest that great longitudinal faults might be formed near coast lines when the gradual overloading of the balanced crust by depo- sitions of sediment produced a strain too great to be relieved by flex- ure. A rupture would then occur, the strata going:down on the overloaded side of the fault and up on the other until equilibrium of pressure upon the yielding magma below was restored by lateral displacement of the magma. The fault so formed would present a diminished resistance to dislocation, and if the action which origi- nated it should continue, it would be likely to increase in dimensions both in length and in the amount of vertical displacement. This action might even continue after the emergence of the region above the surface of the water, provided a more rapid denudation of the landward than of the seaward side of the fault took place, in which case a continued disturbance of equilibrium would be accompanied by vertical yielding, increasing the amount of dislocation, and by sub- terranean movements of the supporting magma, whereby a restora- tion of material would be effected from overloaded to denuded areas. Moreover, the hypothesis of a constant restoration of disturbed equilibrium makes it easier to understand why the folding of strata should grow steeper, even to a folding under, as the axis of a moun- tain chain is approached. A diagram exhibiting the so-called “fan-like structure of the Alps,” enlarged from a figure by Rogers, (see Rogers’ Report on the Geology of Pennsylvania, Vol. II, p. 902,) was shown in illustration. The gradual subterranean move- ments inward under a mountain chain, as the upper portions were removed and the remainder elevated, would carry the strata along on a support of diminishing width until they were folded upward and backward. The gradual increase towards the east in the amount of corrugation and steepness of dips, together with the supposed reversed folding by which the rocks of the eastern part of the Appalachian region seem to _ 32 PHILOSOPHICAL SOCIETY OF WASHINGTON. dip under older rocks, still further east appear, therefore, to favor the notion that the paleozoic rocks of the Appalachian region and the eastern part of the Mississippi basin were derived from the erosion of highlands formerly existing east of the Appalachian chain, now, perhaps, submerged in the Atlantic ocean. The downthrow of a fault, if formed in the manner supposed in the region under con- sideration, would accordingly be on its western side, as suggested above. The third communication was by Mr. S. F. Emmons on , ORE DEPOSITION BY REPLACEMENT. [ Abstract. ] After a few introductory remarks upon the relatively unsatis- factory condition of that branch of geology which treats of ore de- posits, considering the early date at which it was taken up, the speaker briefly reviews the existing theories and classifications, and shows that they are mainly based on the idea that each ore deposit is the filling of some pre-existing cavity or opening in the rock in which it is now found ; that so-called fissure veins, for instance, were once actually open cracks, and that irregular deposits in limestone have been made by the filling up of open caves, such as so fre- quently occur in these rocks. The result of his studies of the so- called “carbonate deposits” of Leadville, Colorado, has been to show that they are not the filling up of pre-existing cavities; the caves there have been formed since the ore was deposited, as is proved by their crossing indiscriminately ore bodies and limestone. ‘They belong to a class of deposits for which he proposes the name metamorphic deposits, or those which have been formed by a meta- somatic interchange between the vein and original rock material. In Leadville the principal deposits are an actual replacement of the limestone itself at or near the contact of this stratum with an overlying sheet of porphyry. This replacement action has in places proceeded so far that the entire stratum of ore-bearing limestone or dolomite, originally 150 to 200 feet thick, has been cHanged into vein material, which consists of silica and metallic minerals. This vein material was brought in solution by percolating waters, which had taken it up during their circulation through the adjoining and generally overlying eruptive rocks. A more detailed description of the phenomena of these deposits will be found in his paper en- GENERAL MEETING. 33 titled ““ Abstract of a Report on the Geology of Leadville,” in the Second Annual Report of the Director of the United States Geo- logical Survey. While the speaker’s studies have thus far been mainly confined to limestone deposits, he has reason to believe that essentially the same process has produced a large proportion of ore deposits in crystal- line and eruptive rocks, and that to the class of metamorphic de- posits belong most of the so-called fissure veins of the Rocky Moun- tain region. That is, that they are not the filling in of pre-existent open fissures by vein materials foreign to the adjoining rocks, but simply a metamorphic change of these rocks themselves along channels of easy access to percolating waters; and according to the character of the material held in solution by these waters, these rocks have been more or less changed into quartz and metallic min- erals, to a greater or less width, as the case may be. Numerous instances of such veins will be found in the forthcoming Census Report upon the Statistics and Technology of the Precious Metals, by Mr. G. F. Becker and the speaker. 234TH MEETING. Aprit 21, 1883. Vice-President Britiincs in the Chair. Forty members present. The Chair announced that Messrs. WASHINGTON CARRUTHERS Kerr and SAMUEL FRANKLIN Emmons had been elected members. Mr. W. H. Datu addressed the Society on GLACIATION IN ALASKA, illustrating his remarks by maps of the territory and of the glacial areas of the St. Elias Alps and Kachekmak Bay, Cook’s Inlet, the latter being from surveys made by him under the direction of the U.S. Coast Survey. He called attention in the first place to the wide differences in the character of the masses of ice resulting from the consolidation of snow by gravity (which would usually be classed as glaciers), as observed by him during nine years’ exploration in Alaska. These might be classed under several heads: as plateau-ice, filling 34 PHILOSOPHICAL SOCIETY OF WASHINGTON. large areas of depression and without motion as a whole, but when sufficiently accumulated overflowing the edges of its basin in various directions; as valley-ice, filling wide valleys of gentle incline both as to their axes and their lateral slopes, producing masses of ice moving in a definite direction but without lateral and sometimes even without terminal moraines; as ice-cascades, formed in sharp nar- row ravines of very steep inclination, usually without well-defined surface moraines; as typical glaciers, showing névé and lateral and terminal moraines; and lastly, as effete or fossil glaciers, whose sources have become exhausted, whose motion has therefore ceased, and whose lower portions have become smothered by the accumu- lation of non-conducting débris. The very existence of one of these last has remained unknown for half a century, though the plateau underwhich it is buried has been described and mapped by explorers. Another form under which ice appears in Alaska is that of solid motionless layers, sometimes of great thickness, interstratified with sand, clay, etc. A deposit probably of this character is described by Nordenskiéld, on the Asiatic coast, near Bering Strait. In Alaska this formation, in which ice plays the part of a stratified rock, extends from Kotzebue sound, where the greatest known thickness of the ice-layer, about three hundred feet, has been noted, around the Arctic coast, probably to the eastern boundary.- In Kotzebue Sound the ice is surmounted by about forty feet of clay containing the remains of fossil horses, buffaloes (Bos latifrons, etc.), mountain sheep, and other mammals.. Farther north the ice is covered with a much thinner coat of mineral matter or soil, usually not exceeding two or.three feet in thickness, and rarely rises more than twelve or fifteen feet above high water mark on the sea coast. Its continuity is broken between Kotzebue Sound and Icy Cape by rocky hills composed chiefly of carboniferous limestones, which bear no glaciers and do not seem to have been glaciated. The absence of bowlders and erratics over all this area has. been noted by Franklin, Beechey, and all others who have explored it. The remarkable extent and character of the formation was unknown previous to the speaker’s investigations, though the“ice cliffs of Kotzebue Sound had attracted attention from the time of their first discovery. Mr. Datu desired especially to emphasize the distinction between these strata of pure ice and the “frozen soil” so often alluded to by arctic explorers. The absence of frozen soil in the alluvium GENERAL MEETING. 85 of the Yukon Valley, far north of Kotzebue Sound, was noted, as well as the fact that this valley has, for some unexplained reason, a mean temperature considerably above the normal, so that its forests extend well beyond the Arctic circle. The distribution of glaciers, properly so-called, in Alaska, as far as our present knowledge goes, is confined to the region of the Alaskan range and the ranges parallel with it south of the Yukon Valley, but particularly to the coast mountains bordering on the Gulf of Alaska and the Alexander Archipelago, of which the Saint Elias Alps form the most conspicuous uplift. The distribution of stratified ice is all north of the Yukon Val- ley, which divides the two regions. Hence, for the glacial epoch, it may be presumed that the one is the equivalent of the other, and the fact that Arctic Alaska is marked by stratified ice, rather than glaciers such as those of Greenland, must be due to local geological and climatic peculiarities existing at the time. On the Asiatic coast, especially at Holy Cross Bay, in nearly the same latitude and with not very different topographic conditions, glaciers are abun- dant at the present time. On the mainland, facing the Alexander Archipelago, especially toward Lynn Canal, Icy Strait and the Stikine region, local glaciers are abundant, and traces of others, now dissolved, may be found on the lowlands of most of the islands. That these were always local, though doubtless very extensive, and that they were the pro- geny of the topography instead of being its parent, is obvious to anyone who has seen the coasts of Maine or Norway, which have been submitted to general glaciation, and will compare their rounded, worn, and moutonnée aspect with that of the sharp cliffs, beetling crags, narrow valleys, and scanty lowlands of the Alaskan islands. The speaker concluded, from his observations, that the extent of the Alaskan glaciers is greatly diminished from its former state, and is probably still diminishing; that the southern portion of the Territory is probably nearly or quite stationary, while the northern part is undergoing elevation; and that, from the nature of the case, the area of stratified ice cannot be expected to increase or di- minish materially without changes in geological or climatic con- ditions too great to be anticipated. Mr. Atvorp remarked that on Point Barrow frozen ground had been penetrated to a depth of thirteen feet. 36 PHILOSOPHICAL SOCIETY OF WASHINGTON. In reply to a question by Mr. AntiseLt, Mr. Dawu said that little was known of the humidity of the interior of Alaska; 23 inches of precipitation, nearly all in snow, had been observed in a single year at one point and 12 inches at another. Mr. F. B. Hovueu then read a paper on THE CULTIVATION OF THE EUCALYPTUS ON THE ROMAN CAMPAGNA, which was discussed by Messrs. E. B. Etuiorr and H. FarquHar. It is published in the American Journal of Forestry for June, 1883. 235TH MEETING. May 5, 1888. Vice-President Briir1nes in the Chair. Twenty-seven members and visitors present. The Chair announced the election to membership of Messrs. Wixi1AM THomas SAMPSON, JOHN OscAR SKINNER, and THomaAs CROWDER CHAMBERLIN. The first communication was by Mr. H. A. Hazen on HYGROMETRIC OBSERVATIONS. [ Abstract. ] After describing the various devices by which the moisture of. the air has been measured, and especially the novel and valuable apparatus of Crova, the speaker illustrated the difficulty of the subject by contrasting synchronous determinations made at four points within a radius of two miles, and then described some ex- periments tending to show the inaccuracy of the wet and dry bulb hygrometer, as ordinarily observed. The value of the wet bulb reading is enhanced by blowing on the bulb with a bellows, or otherwise subjecting it to a brisk current of air. . Mr. Harkness remarked first, that Mr. Hazen’s experiments appeared to prove the insufficiency of Regnault’s formula, for they showed the difference between the indications of the wet bulb and dry bulb to be a function not only of the humidity, but of the velocity of wind; second, that height of station above the ground GENERAL MEETING. 37 was a condition to which too little attention had been given; and third, that there seemed a possibility of obtaining a slightly erro- neous vapor tension with Crova’s apparatus. Mr. E. J. Farquuar then read a paper on DREAMS IN THEIR RELATION WITH PSYCHOLOGY. [ Abstract. ] Several theories of dreams were considered and none found en- tirely sufficient; not because a new and complete one was to be proposed, but because all seemed a little too partial and limiting in their scope. After touching on the relation of dreams to sleep and to waking, as intermediate between them, discrediting many recorded experiments on the ground of their being vitiated by a special pur- pose latent in the mind, and pointing out that the usual supposition of our being often waked by the intensity of a dream appears to put cause for effect, since it must be the fact of waking that effects the dream, perhaps by slow degrees—the character of mental opera- tions in dreams was discussed. Dissent was expressed from the opinion that the dreaming state is devoid of such originating power as belongs to the waking; this position was maintained by showing _ first, the extreme vividness and lastingness of impression often per- taining to dreams, apart from any features of horror; then the coherence, far from being unknown among them, yet of a peculiar kind ; and, finally, the true significance occasionally appearing in them, generally by figurative shape, amounting sometimes to a real enlightenment of the mind. Regarding the faculties or aspects of mind most apt to display themselves in dreams, it was held that all were liable to the exercise in turn, though some of the higher ones, especially the moral sense and judgment, less than others; since these expressed a rarer and more distinctive force evolved and laid up by and for our relations with actual life, while other powers whose exercise is less of an expenditure from the most important vitalities of mind were freer at the time—the principles of conservation and struggle for existence being thought to apply among the mental elements. Thus, to a certain degree, the mind may be seen more clearly in its true character by means of dreams than awake, though in very partial views at a time. Unconscious mental action was reviewed in this connection, and it was held that not only the lower processes, called reflex, but many of the highest functions 38 PHILOSOPHICAL SOCIETY OF WASHINGTON. largely partake of this attribute. A great number of other points in regard to dreams were merely named as illustrating the fertility of the subject. 236TH MEETING. May 19, 1883. Vice-President HrtGarp in the Chair. Forty members and visitors present. It was announced from the General Committee that the following rules had been adopted : I. If the author of any paper read before a section of the Society desires its publication, either in full or by abstract, it shall be re- ferred to a committee, to be appointed as the section may determine. The report of this committee shall be forwarded to the Publica- tion Committee by the secretary of the section, together with any action of the section taken thereon. II. Any paper read before a section may be repeated, either en- tire or by abstract, before a general meeting of the Society, if such repetition is recommended by the General Committee of the So- ciety. Mr. Ropert FLETCHER made a communication entitled RECENT EXPERIMENTS ON SERPENT VENOM. It is published in the American Journal of the Medical Sciences for July, 1883. Mr. H. FarquuAr then made a communication on FURTHER EXPERIMENTS IN BINARY ARITHMETIC, showing that the relation between the vertical and horizontal di- mensions of the characters used in the binary notation is a factor in determining its economic value. He presented, also, the results of a series of comparative tests showing that the binary notation enables some persons, after brief practice, to perform addition more rapidly than with denary notation, while with others it requires a longer time. The latter class includes practiced computers, gene- rally, and the former those less accustomed to the use of figures. GENERAL MEETING. 39 Mr. DoorirrLe remarked that the most instructive results would be obtained by experimenting with young persons; and the subject was further discussed by Messrs. W. B. Taytor, E. B. Exxiott, and C. A. Scuort. 237TH MEETING. JUNE 2, 1883. Vice-President HinGarp, and afterward Mr. HarKkwness, in the Chair. Twenty-two members present. It was announced that the next meeting would be held October 13th. Mr. W. Lee made a communication, with illustrations, entitled SKETCHES FROM MEDALLIC MEDICAL HISTORY. ; [ Abstract. ] The paper was prefaced by remarks on the value of coin and medal collecting as a profitable means of instruction, and by a recog- nition of the danger to which collectors are exposed of develop- ing a mania for collecting odd and curious things which cease to be instructive. An extended interest in numismatics commenced to show itself in this country in 1858, at which time there were probably not as many as one hundred coin collectors in the United States. The interest has grown rapidly, however, until now there must be on the books of the United States Mint the names of at least one thousand collectors who receive yearly the issue of the mint, with a special proof polish. In New York alone, during the year 1882, there were thirty-nine collections sold at public auction, the amount realized being '$68,441.36. The largest of these was the Bushnell collection, which realized $13,900.47. Sev- eral of our large cities have numismatic societies, some of which are designated as numismatic and archeological societies; and a number of periodicals devoted simply to the interest of numis- matics obtain a satisfactory circulation. . The modes of striking off coins and medals were given somewhat in detail, and attention was then called to the important part which medals struck in honor of medical men and to commemorate im- 40 PHILOSOPHICAL SOCIETY OF WASHINGTON. portant events bearing directly upon the history of medicine have played throughout the history of the world. The illustrations of the paper included a hundred and fifty examples of the medals themselves, in regular sequence, from the days of Roman and’ Greek medicine down almost to the date of the paper itself, an interesting commemoration of events and individuals marking epochs in the history of medicine. These medals were taken up seriatim, references were made to the lives of individuals and the scientific work done by them, and descriptions were given of the occasions which called for the striking of medals. The paper closed with an expression of hope that the Society might be stimulated at the sight of so many handsome and perma- nent memorials of the men and times of the past, to attempt to preserve the features of its first president, Joseph Henry, in a similar enduring form. The bibliography of the subject was discussed at some length, and the following works were referred to: MeEap, Richardi.—Dissertatio de Nummis quibusdam a Smyrnaeis in medicorum honorem percussis. Naples, 1752. Rupo.put, C. A.—Index numismatum in virorum de rebus_ medi- cis vel physicis meritorum memoriam percussorum. Berlin, Ist edition 1823, 2d edition 1825, 12mo., XII, 131 pp, 3d edition 1828, 4th edition 1829. (This work (2d edition) comprises the description of 523 medals struck in honor of 350 scientific and medical men.) RENAULDIN, Leop. Jos.—LEtudes historiques et critiques sur les Médicins Numismatistes, contenant leur biographie et l’an- alyse de leurs écrits. Paris, 1851, 8°, XVI, 574 pp. (This work contains the names of 61 physicians). CHEREAU (A).—Les mereaux et les getons de l’ancienne faculté de médecine de Paris. L’Union Médicale. Paris, 1873, 3 Series, XV, pp. 309, 321. PFEIFFER, (L) und RuLtanp (C).—Pestilentia in Nummis. Ges- chichte der grossen Volkskrankheiten in numismatischen Documenten. Ein beitrag zur Geschichte der Medicin und der Cultur. Tubingen, 1882, 8 X, 189 PP. Mit zwei Tafeln Abbildungen in lichtdruck. Wrornu, Warwick.—Asklepios and the Ceins of Pergamon. From the Numismatic Chronicle and Journal of the Numismatic Society. London, 1882, Part I, Third Series, No. 5, pages 1 to 51, plates 3. Moeusen, J. C. G.—The exact title of this author’s work is not known to the writer of the paper; it was written in German, GENERAL MEETING. 41 and embodies a description of a collection of medals in Berlin struck in honor of physicians, giving 200 medals struck after the 15th century. GROTEFEND, C. L.—Die Stempel der Rémischen Augenirzte. Hannover, 1867. Mr. T. N. Gixiu then made a communication on ANALOGUES IN ZO0O-GEOGRAPHY. 238TH MEETING. OcToBER 138, 1883. The Society, in accordance with the notice of adjournment at the June meeting, resumed its sessions. The President in the Chair. Forty-four members and visitors present. It was announced that during the vacation the Society had lost by death Surgeon General C. H. Cranz, one of its Vice-Presidents ; Admiral B. F. Sanps, one of its founders; and Dr. Jostan CurRTIs. It was further announced from the General Committee that Mr. Garrick MALLERY had been appointed Vice-President to fill the vacancy occasioned by the death of Mr. Crane, and that Mr. C. V. Rizey had been added to the General Committee to complete its number, Mr. Wii.14m B. Taytor read a paper entitled NOTE ON THE RINGS OF SATURN. [ Abstract. ] After an historic sketch of the varying and apparently incon- gruous observations by astronomers on the markings and aspects of the Saturnian rings, down to those of Schiaparelli of the Milan Observatory, (published in June last,) Mr. TayLor remarked that since the mathematical discussion by Prof. J. Clerk Maxwell, in 1857,* both the rigid and the fluid ring theories have been aban- doned ; and the discrete or meteoric constitution of the rings is now accepted by all physical astronomers as conclusively established. * On the Stability of the Motion of Saturn’s Rings. 4to. 71 pp. and 1 plate. Cambridge, Eng., 1859. 7 42 PHILOSOPHICAL SOCIETY OF WASHINGTON. Reference was then made to the startling announcement by Otto Struve, in 1851, that a careful comparison of the earlier with the later measurements showed that during the two hundred years of observation the rings had been widening, and the inner edge steadily approaching the body of the planet.* Considering the necessarily vast antiquity of the Saturnian system, such a change during the brief interval of human existence seems @ priori almost infinitely improbable. The hypothesis of some that a meteoric ring has been drawn in by Saturn’s attraction, within comparatively recent ages, seems entirely negatived by the circular symmetry of the system. It is not surprising, therefore, that Struve’s inference has been re- ceived with an almost universal incredulity by the astronomical world. Robert Main, of the Greenwich Observatory, from a dis- cussion of his own measurements taken in the winter of 1852-3, and in 1854, disputed the accuracy of Struve’s measures ; and con- cluded that “no change has taken place in the system since the time of Huyghens.”+ And Prof. F. Kaiser, in a paper on “The Hypothesis of Otto Struve respecting the gradual increase of Saturn’s Ring,” etc., arrives at the same conclusion, and believes “there exists no reason whatever for supposing that the compound ring of Saturn is gradually increasing in breadth.” { There seems to be little doubt of some unintentional exaggeration in Struve’s tabulated results, which range from 4”.6:6”.5 for the ratio of ring breadth to space between ring and ball, in the time of Huyghens, 1657, to 7”.4:3”.7 for the ratio of breadth to space, by his own observation in 1851. Nevertheless it is a noteworthy fact that all the early drawings of Saturn made in the seventeenth cen- tury (many of which are figured by Huyghens in his Systema Sat- urnium, 1659) plainly exhibit the width of the ring as sensibly less than the dark space within; while all modern observers would agree that the bright ring is now wider than the dark space, in about the ratio of 8:2; or were we to take the average of the esti- * Recueil des Mémoires présentés [etc.] par les Astronomes de Poulkoya. 4to. St. Petersburg, 1853. Vol. I, pp. 349-385. ‘Sur les Dimensions des Anneaux de Saturne.” (Memoir read before Acad. Sci.) A brief abstract Of the memoir is given in the Monthly Notices, R. A. S., November 12, 1852. Vol. XIII, pp. 22-24. \ + Monthly Notices, R. A. S., December 14, 1855. ~ Vol. XVI, pp. 30-36. t Mem. Acad. Sci., Amsterdam, 1858. A translation of the memoir is given in the Monthly Notices, R. A. S., January 11, 1856. Vol. XVI, pp. 66-72. GENERAL MEETING. 43 mates of the last century, it would probably not vary far from 5”.25:5”.75; while the general average for the present century would probably be about 6”.5:4”.5. There seems, therefore, to be a real difference, not accounted for by inferiority of earlier instru- ments and estimates, nor by the existing uncertainties of modern measurements. The question will probably be definitely settled in less than a century. Meanwhile there is a need of some explana- tion of the apparently systematic and progressive divergence first pointed out by Struve; and we naturally ask, What indications are afforded by theory ? The elder Herschel, in 1789, (at the Saturnian equinox, when the edge of the ring was presented to view,) from supposed observation of protuberances moving on the line, believed that he had detected a rotation, whose period he estimated at 10h. 32m. 15s., for the outer edge of the ring.* The correctness of this interpretation was controverted by Schroeter, from observations at Lilienthal, on the next passage of Saturn’s equatorial node in 1803; as it was after- ward questioned by Prof. G. P. Bond, of Harvard Observatory, from observations in 1848.+ It is scarcely doubtful that Herschel’s period was derived from an entire misconception of the nature of the ring—which he firmly held to be solid—and that it possesses no scientific value whatever. A. Secchi, from certain recurrent irreg- ularities of phase observed at Rome in 1854, 1855, and 1856, in- ferred a rotation period of 14h. 23m. This is doubtless a nearer approximation (for the outer edge of the ring) than Herschel’s es- timate. It is not probable, however, that the period of any portion of the ring will be determined by observation. Accepting the meteoric theory of the rings as now established, we may by Kepler’s law compute with confidence the period of rotation of any part of the ring; and we thus find— From the period of the inner Satellite (AZ@mas)_._. 22h. 373m.— The period/of ‘otter edge ofiring -L 2 JL kee sisi} obs | eet) bene os dividing. stripe js s oe eee eer eDED. 20), ge inner edge of bright ring _-_-_-___ Tog sk 20 oe inner edge of dusky ring _--_-_--.-- 5h. 45 m. Mean period of ring (supposed solid) about _--_-_ Ioh. 50 m. ‘The period of the planet Saturn is . > ‘ 10h. 14m. * Phil. Trans. Roy. Soc. 1790: Vol. LXXX, p. 479; and 1792: Vol. LXXXII, p. 6. j Gould’s Astronomical Journal. 1850. Vol. I, pp. 20, 21. 44 PHILOSOPHICAL SOCIETY OF WASHINGTON. Thus regarding each constituent element of the ring as having its own independent rotation, (a condition absolutely essential to the stability of the system,) we may consider that from the compli. cated and variable perturbations by the exterior satellites, no one particle can revolve in a circular orbit, and hence that in a space so crowded there must be a considerable amount of interference, The collisions at intersecting orbits may result in heat or in disin- tegration; but in any event they must tend to a degradation of motion, and hence to a slightly shortened mean radius-vector and a shortened period. Theoretically then such an effect as that indicated by Struve would seem inevitable, whether as a matter of fact it has been sufficient in a couple of centuries to be detected or not. And this involves a modified conception as to the earlier condition of the Saturnian rings. To suppose a fine web of nebulous matter con- tinuously spun out from Saturn’s equator, with an unchanging balance of centrifugal and centripetal forces during the long ages while the planet was slowly contracting to one-half its radius, is certainly no easy task or plausible theory. If, however, we are now beholding but a stage of transitional development of the ring, we shall have to imagine its primitive radius considerably larger, and its width as probably very much narrower—so narrow indeed as to have a planetary or satellitic status, revolving in a single definite period—possibly that of Mimas the nearest satellite. Such a ring would present a condition of comparatively great stability ; and it may have been that only the secular recurrence of rare and remarkable conjunctions commenced upon it the work of disturbance and disintegration. When Galileo, the first to see the strange appendages to Saturn, (though without being able to distinguish the anse as parts of a ring,) observed, in 1612, that they had entirely disappeared, he wrote in some dismay, “ Has Saturn possibly devoured his own children?” * So may perhaps the future astronomer, seeing but an airy trace of the historic ring, repeat the saying, Saturn has indeed devoured his offspring; not indeed completely, for*a part will © probably still remain ; nor with violent catastrophe, for the scattered fragments falling by their eccentricity will be absorbed as gently as are the meteors daily falling on our earth. * Third letter to Marc Velser, December 1, 1612. Ofjere di Galileo. 4toi 4 vols. Padua, 1744: Vol. II, p. 123. GENERAL MEETING. 45 A subsidiary point deserving of notice is the certainty that the inner portions of the bright ring (and still more those of the dusky ring) are revolving in periods three or four hours shorter than that of Saturn himself. When Professor Hall made his brilliant discov- ery of the satellites of Mars, and announced that the inner satellite (Phobos) was found to have the short period of 7h. 38m. (or less than one-third of that of Mars) the fact was at once proclaimed by some as incompatible with the “nebular hypothesis.” Everybody knows that the rotation periods of the’sun and planets do not con- form to the third law of Kepler. Our own moon has an actual velocity in its orbit more than double that of our terrestrial equator. And had the moon a little less than one-third its present distance, (that is, were its radius-vector less than 70,000 miles,) its angular velocity would exceed that of the earth, or its period would be less than 24 hours. Or, stated in another way, our earth, if expanded to the orbit of the moon, (under the most favorable disposition of form and of homogenous density,) would occupy considerably more than a year in completing its rotation. The supposed nebular diff- culty is therefore just as pertinent to our own satellite as to those of Saturn or of Mars. The obvious solution is, that all the planets (without exception) have lost a very large amount of rotatory energy ; and this may be largely or chiefly ascribed to the retarding effects of internal friction resulting from solar tides. And, given time enough, the rotation of every planet should be finally reduced to the lunar condition of a precise accord of its diurnal and annual periods. On any hypothesis whatever, it is certain that the rotations of the planets are very much slower (notwithstanding too the acceleration due to contraction) than they originally were. This fact certainly offers no objection to the nebular hypothesis. “ Mr. Durron questioned the validity of Ennis’ hypothesis, that the rotation of a nebular mass could be initiated by purely internal movements. Other remarks were made by Mr. FrisBy. Mr. S. M. Burnett then made a communication on THE CHARACTER OF THE FOCAL LINES IN ASTIGMATISM, showing that the two lines which limit the focal interval of Sturm have been erroneously assumed to be straight. There is only one _ 46 PHILOSOPHICAL SOCIETY OF WASHINGTON. special case of the triaxial ellipsoid in which they are straight. In all other cases they are curved. The full text of this paper may be found in the Archives of Ophthalmology, Vol. XII, Nos. 3 and 4. Mr. H. A. Hazen followed with a communication on THERMOMETER EXPOSURE. [ Abstract. ] Without entering upon the question, Where in any locality shall the air temperature be observed, it is proposed to discuss the even more important question, What shall be the environment of a thermometer that it may give the true temperature. ‘The practice has been very various: in England the Stevenson shelter is re- garded as a standard: this is a double-louvred frame, wholly of wood, 18 x 10 x 18 inches, and placed about 4 feet above grass. In Russia we find a large wooden outside shelter of single louvres open to the north, inside of which is placed a metallic screen, the whole being exposed 12 or 13 feet above grass. In any exposure we should seek, first, to allow the freest possible access of the outer air, and second, to screen the thermometer from direct sun heat, from precipitation, and from radiation, whether (a) from surrounding objects by day or (6) to the sky at night. It is important that we adopt some ready means of accurately determining the air temperature which may answer as a standard of comparison. This we have in the swung thermometer, which, by its free motion through a large body of air shaded from direct sunlight in the daytime, is calculated to give good results. Experiments have been tried with a so-called “ Pattern” shelter constructed of wood,.of single louvres, inclined 30° to the hor- izontal, thus giving a good air circulation. The size is 4x3x3 feet, and it is erected at a height of 13 feet above a tin roof. In order to determine the Jeast admissible size for a shelter, thermom- eters were placed in the Pattern 5 inches apart and running in an east and west direction, and these were observed morning and after- noon. It has been found that with a hot sun and still air the heat from the louvres rapidly diminishes with distance and becomes in- sensible at 15 inches. Comparisons have also been made for several weeks between the: Russian and Pattern shelters; and the means of 100 sets of continuous observations on a still day, and again on a windy day, are shown n the following table: ‘ GENERAL MEETING. 47 Dry ther- Wet ther- Relative humidity ; mometer. mometer. per cent. Russian. Pattern. R. BE: I P StU alr See ACTS isha 64°.0 62°.7 52.4 S10 Light south wind-_ 77 .2 “Wien 62.0 61.0 3087) 134.5 These results show directly the advantage of a good circulation of air, and that after shielding from the sun and radiation to the sky with a shelter at least 3 feet long, we may neglect other consid- erations. Experiments are still in progress to determine the proper height above sod or roof, the proper exposure for a north window, and so forth. Mr. ANTISELL, referring to the general theme rather than to the special subject of the paper, took occasion to note that the practice of conducting meteorologic observations on the tops of highshouses, while it may well subserve the special purposes of the Signal Service, renders their work of materially less value to the medical profession. There is so much change, especially of the moisture element, in the first few feet from the ground upward that no observations can be depended upon as reporting the conditions of the phenomena of disease unless they are made in the layer actually occupied by man. Mr. Taytor asked whether there might not be an error arising from the set given to the glass of the bulb by the pressure of the mercury of a whirled thermometer. Mr. HazeEN replied that he had tested the effect of pressure ap- plied to the bulb with the finger, and found that the set produced was of very brief duration. He had also tested the thermic effect of the friction on the atmosphere incurred by rapid whirling, and found it inappreciable with a velocity of about fourteen miles an hour. On whirling a black bulb thermometer, he observed a change of several tenths of a degree, which appeared clearly referable to the greater coefficient of friction of the surface roughened by lamp- black. Mr. Granam BExt remarked that if we eliminate radiation and learn the absolute temperature of the air at the point of observa- tion, our knowledge is still limited to that point only, whereas for meteorologic purposes it is important to ascertain the average tem- perature of a body of air. He suggested the possibility of utilizing for this purpose a measurement of the velocity of sound, which 48 PHILOSOPHICAL SOCIETY OF WASHINGTON. velocity is dependent on atmospheric temperature and independent of barometric pressure. Mr. Durron thought that the extreme delicacy of this observa- tion would involve an uncertainty greater than the one which now inheres in the determination. 239TH MEETING. OcTOBER 27, 1883. The President in the Chair. Forty-seven members and guests present. The Chair announced the death of two members since the last meeting—LrEonARD Dunnett GALE and Exisua Foore. : Announcement was also made of the election to membership of Cuar.es DootirrLe WALCOTT. Mr. T. N. Griu made a communication on ICHTHYOLOGICAL RESULTS OF THE VOYAGE OF THE ALBATROSS. Mr. ALEXANDER GRAHAM BELL made the following communi- cation on FALLACIES CONCERNING THE DEAF, AND THE INFLUENCE OF SUCH FALLACIES IN PREVENTING THE AMELIORATION OF THEIR CONDITION. It is difficult to form an adequate conception of the prevalence of deafness in the community. There is hardly a man in the couniry who has not in his circle of friends and acquaintances at least one deaf person with whom he finds it difficult to converse excepting by means of a hearing-tube or trumpet. Now is it not an extraordinary fact that these deaf friends are nearly all adults? Where are the little children who are similarly afflicted? Have any of us seen a child with a hearing-tube or trumpet? If not, why not? The fact is that very young children who are hard of hearing, or who cannot hear at all, do not naturally speak, and this fact has given origin to the term “ deaf-mute,” by which it is cus- tomary to designate a person who is deaf from childhood. “But are there no deaf children,” you may ask, “ excepting those whom we term deaf-mutes?”’ No; none. In the tenth census GENERAL MEETING. 49 of the United States (1880) persons who became deaf under the age of sixteen years were returned as “deaf and dumb.” Such facts as these give support to the fallacy that deafness, unaccom- panied by any other natural defect, is confined to adult life, and is specially characteristic of advancing old age. So constant is the association of defective speech with defective hearing in childhood that if one of your children whom you have left at home, hearing perfectly and talking perfectly, should, from some accident, lose his hearing, he would also naturally lose his speech. Why is this, and why are those who are born deaf always also dumb ? Fallacies Concerning the Dumbness of Deaf Children. The most ingenious and fallacious arguments have been advanced in explanation. George Sibscota,* in 1670, claimed that the nerves of the tongue and larynx were connected with the nerves of the ear, ‘and from this Communion of the vessels proceeds the sympathy between the Ear, the Tongue and Larynx, and the very affection of those parts are easily communicated one with the other. Hence it is that the pulling of the Membrane of the Ear causeth a dry Cough in the party; and that is the reason most deaf men * * * are Dumb, or else speak with great difficulty ; that is, are not capable of framing true words or of articulate pronunciation by reason, of the want of that convenient influx of the animal spirits; and for this cause also, it is that those who are thick of Hearing have a kind of hoarce speech.” The value of Sibscota’s reasoning may be judged of by the further information he gives us concerning the uses of the Eusta- chian tube. “ By this it is,” he says, “that Smoakers, puffing up their Bheeks, having taken in the fume of Tobacco, send it out at their Ears. Therefore the opinion of Alemaeon is not ridiculous, who held that she-Goats did breathe thorough their Ears,” &c., &e. It is easy for us to laugh at the fallacies of the past, but are we ourselves any less liable to error on that account? The majority of people at the present day believe that those who are born deaf are also dumb because of defective vocal organs. Now let us examine * J have been informed that Sibscota’s work, “The Deaf and Dumb Man’s Discourse,” from which the above extracts are taken, is in reality a translation of another work by Anthony Densing, published in 1656. 50 PHILOSOPHICAL SOCIETY OF WASHINGTON. this proposition. It is a more ridiculous and absurd fallacy than that of Sibscota and more easily disposed of. The hypothesis that congenitally deaf children do not naturally speak because their vocal organs are defective involves the assump- tion that were their vocal organs perfect such children would natu- rally speak. But why should they speak a language they have never heard? Do we speak any language that we have not heard? Are our vocal organs defective because we do not talk Chinese? It is a fallacy. The deaf have as perfect vocal organs as our own, and do not naturally speak because they do not hear. I have my- self examined the vocal organs of more than 400 deaf-mutes with- out discovering any other peculiarities than those to be found among hearing and speaking children. The deaf children of Italy and Germany are almost universally taught to speak, and why should we not teach ours? Wherever determined efforts have been made in this country success has followed and articulation schools have been established. Fallacy Concerning the Intelligence of Deaf Children. The use of the word “ mute” engenders another fallacy concerning the mental condition of deaf children. There are two classes of persons who do not naturally speak—those who are dumb on account of defective hearing and those who are dumb on account of defec- tive minds. All idiots are dumb. Deaf children are gathered into institutions and schools that have been established for their benefit away from the general observ- vation of the public, and even in adult life they hold themselves aloof from hearing people; while idiots and feeble-minded persons are not so generally withdrawn from their families. Hence the greater number of “ mutes” who are accessible to public observation are dumb on account of defective minds, and not of defective hear- ing. No wonder, therefore, that the two classes are often con- founded together. It is the hard task of every principal of an institution for the deaf and dumb to turn idiots and feeble-minded children away from his school—children who hear perfectly, but cannot speak. Although it is evidently fallacious to argue that, because all deaf infants are dumb, and all idiots are dumb; there- fore all deaf infants are idiots: still this kind of reasoning is un- consciously indulged in by a large proportion of our population ; and the majority of those who for the first time visit an institution GENERAL MEETING. 51 for the deaf and dumb express unfeigned astonishment at the bright- ness and intelligence displayed by the pupils. Why Hearing Children who become Deaf also become Dumb. I have stated above that children who are born deaf do not natu- rally speak because they cannot hear. For the same reason chil- dren who lose their hearing after having learned to speak naturally tend to lose their speech. They acquired speech through the ear by imitating the utterances of their friends and relatives, and when they become deaf they gradually forget the true pronunciation of the words they know, and have naturally no means of learning the pronunciation of new words; heace their speech tends to become more and more defective until they finally cease to use spoken words at all. Adults who become deaf do not usually have defective speech, for in their case the habit of speaking has been so fully formed that the mere practice of the vocal organs in talking to friends prevents loss of distinctness. We can learn, however, from the case of Alexander Selkirk how important is constant practice of the vocal organs. This man, after about one year’s solitary resi- dence upon an island, was found to have nearly forgotten his mother tongue; and we find that deaf adults who shrink from society and use their vocal organs only on rare occasions acquire peculiarities of utterance that are characteristic of persons in their condition, although the general intelligibility of their speech is not affected. Fallacies Regarding the Nature of Speech. The fallacies I have already alluded to respecting the difference between those who become deaf in’ childhood and those who become deaf in adult life have their origin in a fallacy concerning the nature of speech itself. To most people, who do not reflect upon the sub- ject, it appears that speech is acquired by a natural process similar to that by which we acquire our teeth. Ata certain age the teeth make their appearance, and at another age we begin to talk. To unreflecting minds it appears that we grow into speech; that speech is a natural product of the vocal organs, produced without instruc- tion and education ; and this leads directly to the fallacy that where speech is wanting or imperfect the vocal organs are defective. I have already stated that this cause has been assigned in expla- 52 PHILOSOPHICAL SOCIETY OF WASHINGTON. nation of the dumbness of children who are deaf. The idea gives rise also to the popular notion that stammering and other defects of speech are diseases to be “cured,” and the attempt has been made to do so, even by heroic treatment. It is not so very long ago that slices have been cut from the tongue of a stammerer, in the vain hope of “curing” what was, after all, but a bad habit of speech. I have myself known of cases where the uvula has been excised to correct the same defect. The dumbness of the deaf and the defect- ive speech of the hearing are some of the penalties we pay for ac- quiring speech ignorantly, by mere imitation. If parents realized that stammering and other defects of speech were caused by igno- rance of the actions of the vocal organs, and not necessarily through any defect of the meuth, they would have their children taught the use of the vocal organs by articulation teachers, instead of patron- izing the widely-advertised specialty physicians, who pretend by secret means to “cure” what is not a disease. Speech is naturally acquired by imitation, and through the same agency defects of speech are propagated. A child copies the defective utterance of his father. A school-fellow mocks a stammering companion, and becomes himself similarly affected. In the one case the fallacy that the supposed disease is hereditary prevents attempts at instruction and correction, and in the other the idea that the affliction is the judgment of God in the way of punishment discourages the afflicted person and renders him utterly hopeless of any escape excepting by a miracle. A practical illustration of the fact that defective speech is prop- agated by imitation is shown in my own case. When I was a boy my father was a teacher of elocution, and had living with him at one time one or two pupils who stammered. While under the care of my father, these boys spoke clearly and well, without any ap- parent defect, but, owing to his being called away for a protracted period of time, his pupils relapsed, and the boys commenced to stammer as badly as at first. Upon my father’s return he found a house full of stammerers. His own sons were stammering too! I can well remember the process of instruction through which I went before the defect was corrected in my own case, Ignorance the Real Difficulty in the Way of Teaching Deaf Children to Speak. Speech is the mechanical result of certain adjustments of the GENERAL MEETING. 53 vocal organs, and if we can teach deaf children the correct adjust- ments of the perfect organs they possess, they will speak. The diffi- culty lies with us. We learn to speak by imitating the sounds we hear, in utter ignorance of the action of the organs that accompa- nies the sounds. I find myself addressing an audience composed of scientific men, including many of the most eminent persons in the country, and I wonder how many there are in this room who could give an intelligible account of the movements of their vocal organs in uttering the simplest sentence? We must study the mechanism of speech, and when we know what are the correct adjustments of the organs concerned, ingenuity and skill will find the means of teaching perfect articulation to the deaf. The Old Fallacy—“ Without Speech, no Reason.” I have already stated that children who are born deaf are also always dumb. How, then, can they think? It is difficult for us to realize the possibility of a train of thought being carried on with- out words; but what words can a deaf child know, who has never heard the sounds of speech ? When we think, we think in words, though we may not actually utter sounds. Let us eliminate from our consciousness the train of words, and what remains? I do not venture to answer the ques- tion ; but it is this, and this alone, that belongs to the thoughts of a deaf child. It is hardly to be wondered at, therefore, that the fallacy should have arisen in the past that there could be no thought without speech ; and this fallacy prevented for hundreds of years any attempt at the education of the deaf. Before the end of the last century deaf-mutes were classed among the idiots and insane; they had no civil rights, could hold no property ; they were irresponsible beings. Even those interested in the religious welfare of the world consigned their souls to the wrong place, for “faith comes by hearing,” and how could a deaf child be saved? I say that for hundreds of years the old fallacy, that “without speech there could be no reason,” hindered and prevented any attempt at the amelioration of the con- dition of the deaf. But, strange to say, it was this very fallacy that first led to their education. It was attempted, by a miracle to teach them to speak. In Bede’s History of the Anglo-Saxon church we read “ How Bish- opp John cured a dumme man with blessing him.” 54 PHILOSOPHICAL SOCIETY OF WASHINGTON. “ And when one weeke of Lent was past, the next sounday he willed the poore man to come unto him; when he was come, he bydd him put out his tounge and show it unto him, and taking him by the chinne, made the signe of the holy crosse upon his tounge, and when he had so signed and blessed it, he commaunded him to plucke it in again, and speake saying, speake, me one word, say gea, gea, which in the english tounge is a worde of affirmation and consent in such signification as yea, yea.* Incontinent the stringes of his tounge were loosed, and he said that which was commanded him to say. The bishopp added certain letters by name, and bid him say A; he said A; say B, he said B, and when he had said and recited after the bishopp.the whole cross rewe he put upon him sillables and hole wordes to be pronounced. Unto which when he answered in all pointes orderly, he commaunded him to speake long sentences, and so he did; and ceased not all that day and night following, so longe as he could hold up his head from sleepe (as they make report that were present) to speake and declare his secret thoughtes and purposes, which before that day he could never utter to any man.”’} Now, stripped of the miraculous, this is simply a case of articula- tion teaching. In the other countries of Europe the first attempts at the education of the deaf were also made by teaching them to speak, and as the early teachers were monks of the Roman Catholic Church, it is probable that these schools resulted from the attempts to perform the miracle of healing the dumb. sat, yt | a j ity { : AEDs BULLETIN OF THE MATHEMATICAL SECTION. A communication signed by Mr. J. E. Hilgard and nineteen other members of the Philosophical Society, asking that a Section in Mathematical Science be formed, as provided in Paragraph 6 of the Standing Rules of the Society, was presented to the General Committee at its regular meeting January 27, 1883. The propo- sition was agreed to, and Mr. Hilgard was empowered to call a special meeting for the purpose of organizing such a section; the call being extended to all members of the Society. ist PRELIMINARY MEETING. FEBRUARY 17, 1883. Twelve members met in the library of the Army Medical Mu- seum, in answer to the first call. Mr. Hiiearp not being present, Mr. E. B. Evurorr was called to the Chair. An informal discussion followed, which brought out a unanimous sentiment in favor of forming the Section. With some differences of opinion as to details, it was agreed to postpone formal action, and the meeting adjourned subject to call. 2p PRELIMINARY MEETING. Marcu 5, 1883. Mr. Hiiearp in the Chair. Fifteen members present. A plan of organization was adopted, and referred to the Gene- ral. Committee of the Society for consideration. 12 121 122° PHILOSOPHICAL SOCIETY OF WASHINGTON. Ist Reauitar MEETING. * Marce# 29, 1883. Fourteen members present. In the absence of Mr. HitGarp, who had presided over the meeting for organization, Mr. G. W. H1xu was called to the Chair. The standing rules for the government of the Section, as adopted at the last meeting of the General Committee of the Society, were read. The Section then proceeded to elect officers for the year 1883. On motion of Mr. Wrytock the rules of the Society at its An- nual Meeting were followed. Mr. AsapH Haut was chosen Chairman and Mr. H. FarquHar Secretary. A letter from Mr. Marcus Baker, dated Los Angeles, Cal., was read by Mr. Curistiz. It expressed a strong interest in the Sec- tion, recommending that it should be conducted as nearly as possi- ble on the plan devised by the. late Prof. Henry for the Society itself, by which business and science are kept apart. A free use of pencil and’ paper at the meetings, and seats around a table, were further suggested. The letter closed by advocating the foundation of a new mathematical journal. Mr. CuristTis£ then made a communication on A QUASI GENERAL DIFFERENTIATION, The paper was discussed by Messrs. KumMMELL, Ex.iort, Hint, and DooxitrLEe. The author reserves it from publication to await further research. A resolution was passed, requesting the committee in charge of the matter to call meetings of the Section on Wednesday evenings. 2p MEETING. ApRIL 11, 1883. The Chairman, Mr. Hatt, presided. Present, ten members and two invited guests. It was announced that the Editor of “Science” would publish brief reports of the meetings of the Section. MATHEMATICAL SECTION. 128 The Chairman read an inaugural address, [given in full on pp. 117 to 119 ante.] Mr. C. H. KuMMELL then began a paper on ALIGNMENT CURVES, which was not finished at the time of adjournment. 38D MEETING. APRIL 26, 1888. The Chairman presided. Present, sixteen members and one invited guest. Mr. KuMMELL completed his paper, begun at the second meet- ing, on ALIGNMENT CURVES ON ANY SURFACE, WITH SPECIAL APPLICATION TO THE ELLIPSOID. [ Abstract. ] The attempt to put a number of points in line on a curved sur- face whose normals are supposed to be given (abstraction is made of deviations of the plumb-line and lateral refraction) gives rise to various curves, which I call alignment curves. There are two classes—alignment curves with two given termini and those with a starting point only. There are three distinct curves of the first class, viz.: 1. The normal section, if the surveyor directs his assist- ant to place staffs in line from one end of the line. 2. A curve described if the surveyor would align a point near him, then move up to this point, thence align another point, etc., until the terminus is reached. This process is that used in chaining, or more roughly by a pedestrian going towards a point, and is characterized by requiring only foresights. I call it prodrthode (xpo, 6p@cs, 6dds).* 3. A curve resulting if a backsight is also taken. This curve is therefore defined by the condition that the normal plane at any point of it which passes through one end also passes through the other. I call it diorthode (0:4, épOds, bdds), because it may be con- * This and other names of curves were coined by my friend, Mr. Wm. R. Galt, of Norfolk, Va. 124: PHILOSOPHICAL SOCIETY OF WASHINGTON. sidered straight all through at any of its points. This curve may be considered the ideal curve of a primary base line. Various names have been given to it when on the terrestrial spheroid. Dr. Bremiker, who appears to have first considered it (in his Studien ueber hoehere Geodesie, 1869), proposed the name “ Feldlinie”; that is, field line. He thinks it should be adopted as the geodetic line, because both linear and angular measurements conform to it. Clarke, Zachariz, and Helmert have also mentioned it, the latter, however, only in a note, where he remarks that it deserves no con- sideration in geodesy. To the second class belong two curves: 1. A curve described as follows: The surveyor at the starting point takes his directions from a staff at short distance and directs his assistant to place a staff in the prolongation. Repeating this operation from the first staff, from the second staff, etc., he describes a curve which is well known to be the shortest curve between any of its points. It is usually called the geodetic line. However, since this name would apply at least equally well to the three curves already con- sidered, I propose the name brachisthode (fpaytoros). The proper- ties of this curve need not be considered here, such mathematicians as Gauss, Hansen, Bessel, and others, having perfected its theory. Helmert, in his “ Hoehere Geodesie,” makes this curve the basis of nearly all geodetic computations. The brachisthodic process on a plane evidently results in a straight line, and on a sphere in a great circle. If, on these surfaces, it is in starting directed to a distant point, that point will be reached (disregarding errors of observation). Not so on other curved surfaces; there, in general, the first element of the brachisthode is not in direction to any of its points at a finite distance. 2. The loxodrome being a curve which has a constant inclination to a given direction, may, perhaps, be mentioned as be- longing to this class. The general equations of the two-end curves on any surface may be developed as follows: Let the equation of the surface be: u=f (2%, y, 2) = 0 (1) then if (€, 7, £) is any point in the normal at the surface point (x, y, 2), we have its equations: ae a @) (i) (%) (z) MATHEMATICAL SECTION. 125 and the equation of a normal plane at the surface point (2, y, z) and passing through (2,, 7, 2,), (not necessarily a surface point, but considered so here), is: 0=[ ¢—»(%)-¢-9(&) |Lo-»(Z)-@-9() ] —[o-»(z)-«-9(%) |Le—9(@)-«-9(@) ] =[%—y) €—2)-@—2G—-y)] (=) +[@—)G—-) —%—» €-a1() du + [@—2) €-2) -@-DE-a1(F) © If in this we replace the surface point (2, y, z) by the surface point (2,, y,, z,) and (, 7, ¢) by the surface point (a, y, z) we obtain: du = (G.— 9) @— 2) —@—«) y-wi(F) du +ia— 4) — %)—-G—n) @—4)] aa) “-FLG@,— %,) G—2)— (Ce 2) (x 7 2,)] (37) (4) which, if combined with the equation of the surface, gives the nor- mal section at (2, y,, 2,) through (2,, y,, 2). If, however, we replace in (3) (&, y, £) by the surface point (a, y, 2) we obtain: 0=[(y— y) @{— 2~)—(@, — 2) (y—y)] 3) +{[@-9M-y) -—G-NG-4] (iz) + —2) @—2)-@-)@—29) (7) 6) and this, combined with the equation of the surface, gives the dior- thodic curve. As we move along the diorthode, (5) may be considered a plane which turns about the chord (1, 2) as an axis, so as to be always normal to the surface. It follows that the normals at any point of the diorthede are constrained to pass through the chord. They will thus generate a ruled surface, whose equation is not (5) however. 126 PHILOSOPHICAL SOCIETY OF WASHINGTON. The equation of this ruled surface is obtained by eliminating 2, y, z from (1), (2), and (5). It is important to remark that the dior- thode does not consist of parts which are diorthodes with respect to their termini, otherwise the normals would at the same time pass through two chords from the same point and the curve would be a plane curve. Dr. Bremiker had erroneously supposed that the diorthode was touched by the normal planes. This is only the case at the termini. He has been criticized by Dr. Bruns of Pulkowa and by Helmert, but neither critic has shown the existence of a curve possessing this property, namely, the prodrthode, in which the nor- mal plane at any of its points passes through the consecutive point and the forward terminus, but not in general through the starting point. If then in (5) we replace (,, y,,2,) by («+ dz, y+ dy, z+ dz) we have: 0=[y.—y) de— (e,— 2) ay (FZ) +[@—2)dy— (de ($2) + [(a,— x) dz — (z,— z) dx] (3 ai Gi aaa s>2) 7) 1@ +[@-9 (SE) =< a -»(¢ a) |e du U +[@- (F) -% —» (Z) Je 6) By means of the equation of the surface (1) and its differential equation d d x o= (34) de + (FH) ay + (FE yd) any one of the variables with its differential can be eliminated. The resulting differential equation being integrated so as to contain the starting point (2, y,, 2), will be the equation of a projection of the prodrthode on a coérdinate plane. The proérthode being differently related to its ends, will be dif ferent furward and backward, while the diorthode is the same for- ward and backward. MATHEMATICAL SECTION. 127 The following diagram will illustrate the relative course of these curves: “normal section tteiete dioTthode Bee proorthode te brachisthode Any surface of the second degree may be represented by z—a\? yp 2 = 0 = |—— v—_| — 8 u=o= (**) 404% a (8) The origin is taken at one of its real vertices, so that (a, 0, 0) is its centre. The equation of the diorthode is then by (5), if we write %,— ©, = AX; J, — J, = AY; 4-444 0=[y— 9) (4-2) —@—2)(U—- DIG C—O +[e%—2)m%—-Y)—-Y—-YNa-AI | +[@%—2)4-)-&@-%) GA- «“)] = Zz = (y, X, — YL, + YX — Ay) ”q “—a + & % — 4% + 24y — ydz) — + (a, 2 — 2, % + waz — zhx) = 1 ns ale 2)n sa (2 1) eta + (2, % — % Yo) a 2 Z + (4, % — 2, 2, + pdz) z + (YX = Yy % — VIG (9) The equations of the chord (1, 2) may be written: brat RL Se Pea AR (10) Every point of the chord, therefore, satisfies (9), and since that 128 PHILOSOPHICAL SOCIETY OF WASHINGTON. represents a surface of the second degree, it must be a hyperboloid of one sheet, for this and its varieties are the only ruled surfaces of that order. In the general form (9) it has a center in finite space. It is then the elliptic hyperboloid ; but if a = p (ora = qor p = q), it has its center at an infinite distance, and it is a parabolic hyperbo- loid. In this case the base surface a satis Ss ae = (11) which is a surface of ei of the Sec degree. If a = p= q, then (9) becomes a plane and the base surface a sphere. (9) is evidently satisfied by the center (a, 0, 0), therefore the intersecting surface always passes through the center of the base surface. I consider now the ellipsoid : 0= 2 x? 2 0O=C+R+5-1 (12) We have then the intersecting surface of the diorthode: # y 0 = %%— 4% + Ay — ydz) + (a, 2% — %, % + Az — 2A) pr @ + (Ys %, — I, % + Yaw — wAy) = (13) Let (0, y,, 2) be the eae wnire ane chord CL, 2) pierces the yz - plane (aw, 0, 2,) “ “ ae. * (z,, ws 0) éc “cc “ce cc “cc xy ‘a “ce then we can easily verify the relations: ts A WRIT WL eRe aan hig AO ba Sipe AX I ear Ax (14) Jee hp Ge re Ae Ay Pig aye Ay (14,) g, = HAS . y, = AAs (14,) and if we assume: a i a, =1— ;@42=1-— > (15,) B b ) ee hy yal (15,) e Bb (15,) MATHEMATICAL SECTION. 129 (13) will take sia of the following annuals forms : 0=42%,—- 4) = {+ Ac (2,— f 2) Fe + Ay (@, — ~ 720) (13"} 0 = ay (2, — a2) + az(a,— fine tar, — ree (13%) The following relations will be much referred to: Y2 ey ah Yx 1 (teat ete (16) Ea il Sie ie I iiaale SG eee 7 x, Yx e, ae %, ; UP z, x, ce x, ‘ Z,.—2 r 4 x y toe yy, eae yx (17) 2 Bm ae a 0=42, ¥, Ze Ys 2, &, (18) Replacing in these Ax, Ay, Az; Y,, 25) 3 Zar Uys Ye Des A ii yak by Gr Ger i wr Borie 5 Ses Bar Fo (19) 2 fy 2 2 2 2 2 Nn 2 “a i B a, we have: 0 = ae Be =a oh “ip aa (16' By Sar i — is — 8, a Tic im a," a a,” wd Pa By ieee A OR, “leat oti a,” ae 8, ee B, os dy” (eu) a, ie nes Vv 0 Saw 7 tn a,” = ay” a? ie (18") and these relations also will be found correct. Because in the equation of the diorthodic surface the terms in x,y, 2 are wanting, there must be lines, perpendicular to the co- ordinate planes, lying wholly in the surface. To determine those perpendicular to the zy- plane, I place = 0 the term in ee de- pendent on z and that in (13") independent of 2, or Ay > A Be 2 O= — yar art n— 7. &) to % vy = — part ;— 2) by (16) and (16! 4 O = ayz, - a+ az(2, — 20) Fs : iG as 2) y by (16) and (16') => 130 PHILOSOPHICAL SOCIETY OF WASHINGTON. Substituting the value of y from the first into ‘the second equation we have: Ys MEM ee) nt 0— Be +sS ie — =) (7-2) 0= a Ts —2,)a+ St «) (4 —_— ) by (17,) and (17,') By lo a v, x x. =i fe y ot) a a eas — ores (Ft) ets ews | 2 Corresponding to the hi a we have: tc Y, Ly — 2, ' Y, %y—, et MAY RI and Se to the second : Cay Y= me _ de “x, (- ni)! az, Be za =i by ly cig Denoting hat constants by %,, 2%, Ys Yq» respectively, we have then the equations of a pair of generatrices of the hyperboloid (13) perpendicular to the zy - plane: xis me by (17,) x Zz eas y= i= y (20,) &. Yx t= Ba My; Y= G2 (20,") Similarly the pair of generatrices perpendicular to the yz - plane: Yx %,. a > er ba 20, yee es ae (20,) Ys 2 aire (Visca Taq (20,") and that perpendicular to the za - plane Z @ ait Va a tila io (20,) &. x, = za rire? a te (20,*) Now the second line of each pair intersects the chord, as may be proved thus: The equations of the chord (1, 2) are any two of the following three equations: LE 6 pte ete (21,) MATHEMATICAL SECTION. 131 at ones (21,) A 21 ange be ye 1 : Now B+ bist a ai + Am ale = 0 and (21,) or (21,) can always be satisfied for some value of z; therefore (20,’) intersects the chord. In the same manner it may be proved that (20,’) and (20,*) intersect the chord. It follows, then, that (20,), (20,), and (20,) cannot intersect the chord, and hence belong to the same system of generation. The equations of a pair of lines intersecting in a given point of the hyperboloid and belonging to different systems of generation can be easily found by the condition that one of them must inter- sect (20) and the other (20). I omit this, but give a remarkable symmetrical form of the equation of the hyperboloid : 0=(e@—%,) (y—4,) (2-4) — (@— &) (Y — Ya) @—%) (22) TF @(Y,2,— Ya%y) + y (2,2, Ta 2, X,) = 2(2, Yq aah x, Y,) — xy (2, —%) — y2(%, — 2.) — 2e(Y, —Y,), because 2,4, 2, = %, Y,% by (18) and (18'). It is immediately evident that this equation is satisfied by equa- tions (20). Itis not uninteresting to prove that it also satisfies (21), or that it contains the chord, since it shows the remarkable plia- bility of these forms by virtue of the relations (16), (17), (18), fo"), (177), (18°). The points (2, Yes 2,)s (®er Yor 2v)» (Lp Yor 2) (Lvs Yar 20)» (ys Yar Za)» (&,, Y,, 2,) form a warped hexagon, which lies wholly in the hyper- boloid, and its sides may be considered six intersecting edges of a characteristic parallelopipedon. These edges are: 1 1 1 A= 5%, —2,)3 B= > y.—9.); C= > @—4,) 3) and the co-ordinates of its center are: 1 1 1 t= 5 (% + %)3 Yor va iy “U3 Se OY (2, + %) (24) and these must be those of the center of the hyperboloid also. Transferring the origin of co-ordinates to this center, we have the equation of the hyperboloid regarding (23) : 0= (@— A) (y— B) (@— C)—(@+ A) V+ B+) (25) 132 PHILOSOPHICAL SOCIETY OF WASHINGTON. From this equation we soon find by familiar processes the lengths and directions of the principal axes. As to the question, Which of the alignment curves should be used in geodesy? I observe that between two intervisible points on the terrestrial spheroid the difference between the course of these curves is so extremely minute that they are practically identical ; we can use then that method of tracing which is most convenient. For the distance of non-intervisible stations I consider the brachis- thode the geodetic line as heretofore, because 1st, the diorthode be- comes impracticable; and 2d, it cannot be divided into portions which are themselves diorthodes. As Assistant Wm. Eimbeck, of the United States Coast and Geodetic Survey, suggested to me, the diorthode proper cannot even be traced between very distant stations, which are intervisible only from very elevated positions, such as high peaks or the usual wooden structures. Thisled me to consider a new class of alignment curves—the apparent horizon alignment curves. The a. h. pro-orthode would be the locus of all points for which the tangent cuts the normal at the forward end; while the a. h. diorthode is a curve, at any point of which a tangent to the surface, which passes through the normal at one end, also passes through that at the other end. The equation (3) being adapted to these changed conditions will furnish also the equations of these curves; and I have thus found that the a. h. diorthode on an ellipsoid has an intersecting surface of the fourth order. Messrs. HARKNEsS and DooLirrLE made remarks on this paper. Mr. Asapu HAtt then made a communication on THE DETERMINATION OF THE MASS OF A PLANET FROM OBSERVA- TIONS OF TWO SATELLITES. [ Abstract. ] M. Struve recommends that the position angle and distance of one satellite from another satellite be measured, instead of referring the place of each to the center of the primary planet; and a series of such measurements on satellites of Jupiter has been begun under his direction at Pulkowa. ‘These observations are found to occupy one-third the time, and are considered two or three timés as accurate as those where the planet is used. The most important advantage of the new method is its freedom from the unknown constant errors attending the old, due to the great difference in size and bright- MATHEMATICAL SECTION. 133 ness of the objects measured. The price to be paid for this ad- vantage is a greatly increased complexity in the computation; for the elements of both orbits now enter into each equation of con- dition, and there are therefore twelve normal equations instead of six to solve. The comparative difficulty may be estimated by the number of auxiliary quantities that must be computed in the solution of 2 equations, namely : Zn (n+1) (n+), which amounts to 77 for n = 6, and to 442 for n = 12; a value nearly six times as great. But it is worth while to bear in mind that the twelve equations, by giving the elements and mean distance . of each satellite, give two values of the planet’s mass. Mr. Harkness called attention to the advantage of substituting an accidental error, be it even a large one, for an unknown constant error. Mr. Taytor criticised the designations usually given to the apsides of satellites orbits as being particular when they should be general. He suggested the terms peri-apsis and apo-apsis, or aphapsis. Remarks were also made by Messrs. KUMMELL and HI Lt. Before adjournment the Chairman replied to some questions as to the new object glass for the Imperial Observatory at Pulkowa; and gave a short explanation of the difficulty of calculating the true anomaly in elliptic orbits, 4TH MEETING. May 9, 1883. The Chairman presided. Present: twelve members and one guest. The report of a committee appointed by the General Committee of the Society to consider matters pertaining to Sections was read. Mr. DooxitrLeE read a paper entitled INFINITE AND INFINITESIMAL QUANTITIES. [ Abstract. ] An infinitesimal may be defined as the result of infinite division ; 134 PHILOSOPHICAL SOCIETY OF WASHINGTON. but the term infinite division probably does not represent the same conception to all mathematicians. If we suppose a quantity divided into a number of parts, and each of these parts subdivided, and similar subdivisions to go on forever, each requiring finite time, we have a conception to which the name infinite division may be given with some appropriateness, but which might better be called eternal division. Such division never reaches a result. But if we suppose the time of each subdivision to be proportional to the magnitude of each part, the entire process is completed in finite time, although no limit can be given to the number of subdivisions. If a point be supposed to have passed with constant velocity over a given distance, there was a time when it had passed over half the distance ; afterward a time when the remaining distance was one-fourth of the original distance; the number of such successive halvings is cer- tainly unlimited; and the result is that there is no remaining dis- tance. This is division infinite but not eternal, and the result seems to be zero. As a point is defined to be position without magnitude, so may an infinitesimal be defined to be quantitative relation without magnitude, The terms infinitesimal, differential, nothing, and zero, are not synonyms. They have the same logical denotation but differ in connotation. Mathematicians usually speak of “the value” or “the true value” of a vanishing fraction, as though any quantity whatever were not a true value. The term serial value is proposed as conducive to clearness of thought. A differential coefficient is the serial value of a vanishing fraction; and a differential or infi- nitesimal may be further defined as zero in serial relation to con- tinuously diminishing quantity. The term infinitesimal is however frequently employed like other terms to denote the symbol of its exact signification. We speak of drawing and erasing lines, meaning the visible symbols of Euclidean lines. Even in our purely mental processes we give the name points to the imagined small volumes that symbolize positions with- out magnitude. In like manner the term infinitesimal is employed to denote the imagined small quantity in approximate relation that symbolizes a relation which becomes exact only when magnitude disappears. e A line is infinite relatively to a point, but infinitesimal, 2. e., zero, relatively to a surface or volume. Every quantity is finite rela- tively to other quantities of its own order—zero relatively to orders I, OE ee MATHEMATICAL SECTION. 135 above and infinite relatively to orders below. A volume is inte- grated from surfaces, a surface from lines, and a line from points. Each integral is infinite relatively to the magnitudes from which it is integrated. As momentum is integrated from motion-genera- ting force, it is infinite relatively thereto. Momentum may also be dissipated by infinitesimal decrements; and it is possible that mo- mentum is always thus dissipated and re-integrated whenever motion is communicated from one body to another; but the prin- ciples of mathematics are equally consistent with the hypothesis that actual contact sometimes occurs, in which case motion is di- rectly. and instantaneously transmitted without dissipation or re- integration. Granting that infinitesimal time requires infinite force, momentum satisfies that condition. This paper gave rise to considerable discussion, in which Messrs. Taytor, Hitt, KuMMELL, and Leravour maintained the legiti- macy of the notion of infinitesimals as real elements out of which quantity is built up; Messrs. E:xiorr, DooLitrrye, and FarquHaR took the opposite ground, preferring the Newtonian view of the Calculus; while Mr. Curistixn, while preferring the infinitesimal method, maintained that no evaluation of continuous quantity, in terms of units as it must necessarily be, could ever be precise or entirely satisfactory, to however small a compass the uncertainty be reduced. Mr. CurisTIE also pointed out some paradoxes to which the usual definitions of curves and tangents appeared to lead. Mr. Exiorr then exhibited some tables to serve as a perpetual calendar, and gave a full explanation how by means of them the day of the week corresponding to that of the month for any year, New or Old Style, B. C. or A. D., could be found. 5tH MEETING. May 23, 1883. The Chairman presided. Twenty members and guests present. The appointment of the committee called for under the new Standing Rule relating to papers read before Sections of the Society was considered. Mr. Tayntor moved that the committee consist of the Chairman and Secretary and a third member to be 136 PHILOSOPHICAL SOCIETY OF WASHINGTON. appointed by the Chair. After some diScussion by Messrs. HARKNEss and ELuiorT it was so ordered, with the additional provision that this appointment be made for each paper separately. Mr. G. W. Hitt made a communication on PLANETARY PERTURBATIONS OF THE MOON, which was yet unfinished when he yielded the floor to Mr. G. K. GILBERT, who made a communication on GRAPHIC TABLES FOR COMPUTING ALTITUDES FROM BAROMETRIC DATA. This paper will appear in the Bulletins of the U. S. Geological Survey. 6TH MEETING. JUNE 6, 1883. The Chairman presided. Present, sixteen members and guests. Mr. G. W. Hit concluded his paper on CERTAIN POSSIBLE ABBREVIATIONS IN THE COMPUTATION OF THE LONG-PERIOD PERTURBATIONS OF THE MOON’S MOTION DUE TO THE DIRECT ACTION OF THE PLANETS. [ Abstract. ] Hansen has characterized the calculation of these inequalities as extremely difficult. However, it seems to me that if the shortest methods are followed there is no ground for such an assertion. The work may be divided into two portions independent of each other. In one the object is to develop, in periodic series, certain functions of the moon’s coordinates, which in number do not exceed five. This portion is the same whatever planet may be considered to act, and hence may be done once for all. In the other portion we seek the coefficients of certain terms in the periodic development of certain functions, five also in number, which involve the codrdinates of the earth and planet only. And this part ofthe work is very similar to that in which the perturbations of the earth by the planet in question are the things sought. And as the multiples of the mean motions of these two bodies, which enter into the expres- MATHEMATICAL SECTION. Tz sion of the argument of the inequalities under consideration, are necessarily quite large, approximate values of the coefficients may be obtained by semi-convergent series similar to the well-known theorem of Stirling. This matter was first elaborated by Cauchy,* but in the method as left by him we are directed to compute special values of the successive derivatives of the functions to be developed. Now it unfortunately happens that these functions are enormously complicated by successive differentiation, so that it is almost impos- sible to write at length their second derivatives. Manifestly then, it would be a great saving of labor to substitute for the computation of special values of these derivatives a computation of a certain number of special values of the original function, distributed in such a way that the maximum advantage may be obtained. This modification has given rise to an elegant piece of analysis. It will be noticed that in this method it is necessary to substitute in the formule, from the outset, the numerical values of the elements of the orbits of the earth and planet. There seems to be no objec- tion to this on the practical side, as for the computation of the inequalities sought no partial derivatives of R, with respect to these elements, are required. The paper is printed in full in the American Journal of Mathe- matics, Vol. VI. Mr. E. B. Evutorr made a communication on UNITS OF FORCE AND ENERGY, INCLUDING ELECTRIC UNITS. SeventH MEETING. NOVEMBER 21, 1883. The Chairman presided. Thirteen members present. * Mémoire sur les approximations des fonctions de trés-grands nombres, and , Rapport sur un Mémoire de M. Le Verrier, qui a pour objet la détermination dune grande inégalité du moyen mouvement de la planéte Pallas. Comptes Rendus de Académie des Sciences de Paris. Tom. XX, pp. 691-726, 767-786, 825-847. 138 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. C. H. KuMMELL read a communication ertitled THE THEORY OF ERRORS PRACTICALLY TESTED BY TARGET- SHOOTING. [ Abstract. ] Sir John Herschel treats a special case in which shots of equal probability are in circles. According to Liagre’s theory target shooting is compounded of two distinct operations, viz., sighting and leveling, each of which is liable to errors, independently fol- lowing the ordinary linear law of error. Some reasons for the in- dependence of these operations are that for sighting the direction of the wind, which does not affect the leveling, must be regarded; and that, on the other hand, leveling only is affected by the range. The consequences of Liagre’s theory will now be developed. Let x = error of sighting and ¢, its mean error; y = error of leveling and «, its mean error ; then it follows that x d — 52 wi e 26x" — probability to hit anywhere at distance z from sighting axis. (1) d a we gree probability to hit anywhere at distance y from y g | leveling axis. (1,) ded Se — - — 2 ’ —— ates 3 “Go probability to hit the point (2, y). (2) FE y7 This probability is the same for any point on the ellipse: Pr 2 9? 1 3 a a= where © = oy Ce 0 e”) (3) x Ag This I shall call, then, an equal probability ellipse; its semi-axes are: ae fy A oe : (4) and r = mean semi-diameter (which is equal to its conjugate). r € Assume ar and : pee ae (5) MATHEMATICAL SECTION. 139 then every point on the equal probability ellipse (3) corresponds to a point (#,, y,) on the circle: #7 + y7 = 7", (6) which is the reduced equal probability circle. Counting directions from the right of the x - axis, let a = direction of (x,y) (7) i= ia “ (@,,Y,), or reduced direction of (z,y) (8) h wots y fy O &x oo fy 9 peewee ee sri sais (9) also = = 7 COS a, (10,) Bee ca y= 7 sin a, (10,) € € s whence dz = ~ cosa, dr — ~r sin a,da, S é een a ae dy = — sin a,dr + — r cos a,da, Transforming, then, (2) to the new variables, 7 and a,, we must replace: dedvan e,.¢,rdrda, e? and thus obtain rdrda, — kad Ont & 2c — probability to hit a point of which (r, a,) is the reduced point. (11) Vg. A» FAN an Fig. 1 exhibits 24 shots of equal probability, on an equal proba- bility ellipse, and their reduced positions evenly distributed over the reduced circle. 140 PHILOSOPHICAL SOCIETY OF WASHINGTON. The probability to hit anywhere on the perimeter of an equal probability ellipse of mean semi-diameter, 7, is found by integrating (11), with respect to a,, through a circumference. It is re r € . Let n, = number of shots on area of equal probability ellipse of semi-diameter 7, and n = total number; then n ar Afi co =f ue MB T= f- we 22@=1—e 26” op Bo 2 —tt = 2e7 (18) 0 o Let r =p; if n,=3n, thon} =e 22.5. p= 7/212 (14) The ellipse : 2 2 + 4=212 (15) x y is then an even chance ellipse, which is hit or missed with equal probability. Eliminating <« between (13) and 14), we obtain: (55)"= (@)" as These formule agree with Herschel’s in form, and have, also, the same signification, in case the precisions of sighting and leveling are equal, for in that case the ellipses (3) and (15) become circles and r, p their radii, respectively. Herschel employs these formule for determining the skill of a marksman, which he defines to be =-, from the number of shots that have fallen on a circle of radius r. Correspondingly, we should have to count the shots that have fallen on an equal probability ellipse, the axes of which have the unknown ratio —., which, as yet, we have no method of finding; € = therefore formule (14) and (17) cannot be employed in their gen- eral signification. If, nevertheless, we count the shots on a circle of radius r and compute a value for p and ¢, we shall come as near to their true values as the problem requires, especially if the precis- ions of sighting and leveling are not very different. This can be MATHEMATICAL SECTION. 141 shown analytically by proving that the probability of hitting the area of the circle x _- y? — ia differs from that of hitting the equal probability ellipse ger Ss ea es a mee by terms of the fourth order, with respect to the difference between the mean errors of sighting and leveling. In computing p by (17) the radius (or mean semi-diameter) 7 is left arbitrary ; it is, however, not at all indifferent; for if we take it very small or very large it will give very unreliable values of p. There must then be a certain magnitude of r giving the most re- - re : ue : rdr — ss liable value of p, anditis that which makes P, = —-é 22 4 ‘ ie aay r maximum. This gives the condition: 0 = zrworse Thus the most favorable value of r for determining p is the 2 2 mean error « and the ellipse on =1 (18) = My is the ellipse of the most probable shot. Placing 7 = ¢ in (13), we have I pe 2 OR06E8.... n I .n, = ( —e z) n = 0.39847 ...n=0.4n nearly (19) The most probable shot is, therefore, the distance of the (0.4n)th shot from the center nearly; also the mean of the (0.4n + m)th, and the (0.4n — m)th shot should, if m is not too large, give a fair value of the most probable shot. Solving (13) for «, we have also Cee 2! n (20) n—N, From the definition of e, and es it is obvious that psa gf a 142 PHILOSOPHICAL SOCIETY OF WASHINGTON. which formule afford a comparison between the precisions of sighting and leveling. We have then el: =] 24 gf c= Jit = ory . as This formula, although laborious for practical use, is the most rigorous measure of skill in shooting, and there is no need of other formule except when shots are lost. In that case it requires an important modification, whereby it loses in rigor if the number of lost shots is considerable. Assuming the precisions of sighting and leveling equal, then the reduced distance r in (12) will be the actual distance s of a shot; and if the target is circular, of limiting radius R, we have nD R j & [s*], Ser oF fi ee o Bays . eG =n} — 2 ze — 2 x = — dt ir The integral P#, f ie ‘ =) é , and similarly Pi,, is tabulated in Chauvenet’s Method of Least Squares (Table IX, appendix, to the argument ¢), and is therefore known. * We have further: ny a can b yy [a] Pals oe f is ee é 2e2? £ dy _ a ze? ; Say 8/20 ane ey 20 a x2 oe = nPt, [Sse = 6 +), ss dives = ne, Pt, (Pt, — tP't,) (25,) 2 9 fete = Here P’t, denotes —+* fy mies e and can also be taken from Chauvenet’s table, £6 100 X difference. Similarly, 1 [y"] = ne,'Pt, (Ph — hP) (25,) By virtue of (24) we have also [a7] Nay ep Abi es / - P%. (25,’) nol 07) Talia hte ae (25,') wll 2, ) and these formule may be used to compute «, and «, by an obvious ab 2 approximative process. They show that «,* > a as it should ‘ab 144 PHILOSOPHICAL SOCIETY OF WASHINGTON. be; but it may, or rather must, happen sometinies that the most n n probable increase of the sum of 2? and y’ or [2*]_ + [y] consistent Nap Nes; with (25’) is << (n —n,,) 6’,b being the smaller limit. Such a re- sult cannot be accepted, being contradictory to the fact that there are n—n,, shots at a greater distance than 6. The following method gives plausible results in that case. Assume [y7], + = yy) 8? (4 ee (25,”) as first approximate value in (25,’), and if ¢,<(<,) adopt (<,) as final value of «,: but if ¢,>(¢,), then proceed in approximating to e, by (25,’). The solution of (25,’) gives, as heretofore, the best value of ¢,. Among the target records of the international shoot- ing match of 1874, at Creedmoor, there are 9 with lost shots, 5 of which give too small an increase of sum of squares, and this means that from the record of the hitting shots it would not appear prob- able that so many shots were lost. Instead of the squares, we may, however, employ first powers of distances; and I shall develop the requisite formule for a circular target and equal precisions. Nap n R ee s? We have [s], k= nf 8 pid e 22 > 0 iss 2 an(— 27 ae NF Re | oe ~_ Be si by (13) ry, * (n ay ils eee )n a (26) if N p=, this becomes ¢ = ae . ; (27) a | Soe The quantity ae rad VE (28) : MATHEMATICAL SECTION. 145 which may be called the average shot, has been recently introduced by the United States Ordnance Department, under the name “radius of the circle of shots,” in place of the extremely defective quantity, the mean absolute deviation, the insufficiency of which was pointed out by Henry Metcalfe, Captain of Ordnance, in the Report of the Chief of Ordnance of 1882. Thus the adopted method of discussion of the precision of firearms, as used by that department, is in agreement with Liagre’s theory, only the shots are not referred to the true center, but to the “center of shots,” viz.: their center of gravity. We have, now, the following three quantities, each of which may be used as a measure of precision, sighting and leveling being equally good. 1, the even chance shot, p. 2, the most probable shot, <, (or mean error of sighting and lev- eling). 3, the average shot, 7,, also called radius of the circle of shots; and they are related to each other as follows: p 2 2a > ONG pe The preceding formule I regard as complete, for practical discus- sion of target records, provided there is no evidence for a constant vitiating cause. If, for example, during a shooting match the wind is blowing constantly in the same direction, the effect of this might be partially revealed by computing for the whole match the quan- tity : = 8 If the sign of this quantity is consistent with the observed direc- _ tion of the wind, it might, perhaps, be proper to refer the shots to a new center, to the right or left of the true center, by this quan- tity. In that case we have, however, he | ne? ‘ - fa" : —1 i In leveling there may be a somewhat constant individual habit of holding too high or too low, which, however, ought not to be eliminated in a fair discussion of a match, although it would be of interest to compute the quantity Ly] Oo n for each marksman and for a whole team. 146 PHILOSOPHICAL SOCIETY OF WASHINGTON. Much less proper, it would seem to me, to regard the position of the axes unknown, and to compute their most probable position. If center and axes are to be determined, 2’ y’ denote the co-ordinates of ashot from a random origin and position of axes, and w the angle of turning the latter into their most probable direction ; then the most probable co-ordinates of a shot are: e=2,+2 cosw+ysinw; y=y,+y cosw — x sinw. Imposing the conditions of a minimum for [27] and [y’], we find v, = — =; (LeJeosw+ fy] sin w) (33) y= — = (iy cos w — [2’] sin w) [?yJ—— (ef tan 2u = ——_,; —*_______ (34) [2] ——{e'P — [y+ — FP These formule have, however, their proper place in the theory of Andre’s “ Fehler-ellipse.” Fig. 2 exhibits an ideal distribution of 45 shots. Each ring con- tains 6 shots, leaving 3 shots between the outer ring and infinity. The dotted circle is that of the most probable shot, and the dashed one that of the even chance shot. The following table refers to the combined target record of the Irish team at 800 yards range, in the international shooting match of 1874, at Creedmoor : MATHEMATICAL SECTION. 147 Irish Team at 800 yards: ¢ = 1.8095 ft.; 90 shots, 88 hits. No. of shots on > circle. 3 Radit. a Theory.| Actual. rs Feet. 0.5 63 | 5 +L1.3 1.0 2226 || 22 +0.8 1.5 43-3 | 47 Pa ot 2.0 62.0 | 58 +4.0 RA ay CR 1.5 Leveling limit__| 3-0 83.5 | 83 -+0.5 35 || 87-5 | 87-+-?| +0.5? 4.0 89.2 | 87-1? ? 4.5 89.8 | 88+? ? No. of shots on ring. Theory.| Actual. 6.3 16.5 20.5 18.7 13-5 Discrepancy. a bo | ie) tn A target of 50 pistol shots at 50 yards range shows similar dis- cordance between theory and practice, which, on an average, may be taken less than 5 per cent. 148 PHILOSOPHICAL SOCIETY OF WASHINGTON. Target of pistol shots at 50 yards range: ¢ = 0.167 ft.; 50 shots, NO Misses. | No. of shots on | No. of shots on circle. ring. Radii. ||- Diserep'y:"|—--_, | Dares: Theory. | Actual. Theory. | Actual. 5 | i es 22. i 0.5 1.5 I +0.5 1.5 I +0.5 1.0 5.9 8 —2.1 4.4 7 —2.6 el 12.2 14 18 6.3 6 +0.3 2.0 19.7 23 —3.3 72 9 —I.5 2.5 27.0 28 —1I.0 ise} 5 +2.3 3-0 Nn 3a 33 +0.7 6.7 5 +17 3-5 || 39-6 37 +2.6 5-9 4 +1.9 4.0 43-2 41 2.2 3.6 4 —0.4 : 4.5 46.0 46 0.0 2.8 5 —2.2 5.0 47.8 47 +08 | 1.8 I +08 | 5.5 48.8 49 —0,2 1.0 2 —1.0 6.0 49.4 50 —o.6 0.6 I —0.4 49-4 50 Mr. ELiiorr gave an example of remarkably close agreement between the distribution of errors by theory and by observation of the chest measurements of 1,516 United States soldiers, reported by Dr. Bulkley at the Berlin Statistical Congress. In five groups the greatest difference was four-tenths per cent. MATHEMATICAL SECTION. 149 Er1egHtH MEETING. DrEcEMBER 5, 1883. The Chairman presided. Fourteen members and guests present. Mr. ALvorpD discussed A SPECIAL CASE IN MAXIMA AND MINIMA, the problem being to find the radius of the sphere that will displace the maximum quantity of liquid from a conical wine glass full of water. The differential co-efficient, when put equal to zero, is in the form of two factors. Equating each to zero, one gives the radius of the maximum sought; the other gives a still larger radius, which proves to be the radius of the sphere just tangent to the centre of the base of the cone, and to the sides of the cone, extended upwards. This gives the minimum displacement equal to zero. Calling a the radius of the base, 6 the height, and ¢ the slant height of the cone, theradius of the sphere producing maximum displacement equals abe Ce — aa fe)? ment equals the radius corresponding to minimum displace- C— a. When the radius is still greater, the sphere does not reach the surface of the liquid, but displaces an imaginary quantity of the same. An analytical expression for this case was sought in vain; the result above is simple, and no square root of a negative quantity appears. By some deyice in the mode of investigation, this imaginary case might appear, as in the question to obtain the radical axis of two circles, discussed by Salmon. Mr. KuMMELL suggested that the close relation between the circle x” + y’ = FR’ and the equilateral hyperbola 2? — y’?= R’, each of which could be regarded as an imaginary branch of the other, might help us to understand many of such difficulties. He showed that the radical axis of two circles not intersecting was the com- mon chord of two equilateral hyperbolas whose major axes were. those diameters of the circles which lie in the same straight line. Mr. EvLLiottr read a communication on A FINANCIAL PROBLEM, in which he gave formule for calculating the advantage of in- 150 PHILOSOPHICAL SOCIETY OF WASHINGTON. vestment in United States Government bonds, at Six or at four per cent., and making use of the banking privileges thus available, over investment at a higher rate without such privileges. The restrictions caused by the high premium on Government bonds, the bank tax, and the necessary specie reserve were all allowed for. This paper was discussed by Messrs. Harkness, DE Lanp, SmILEy, and others. Mr. H. Farquuar presented the following FORM OF LEAST-SQUARE COMPUTATION. Suppose four unknown constants, A, B, C and D, are to be cal- ° culated from equations of condition of the form aA + 6B+cC+dD=y. Arrange columns in order (1) a’, (2) ab, (3) ae, (4) ad, (5) ay, (6) b?, (7) be, (8) bd, (9) by, (10) e*, (11) ed, (12) ey, (18) d’, (14) dy Add up first five columns and place under (2) to (5) the quotients of their sums divided by 2(1). Put the product x) 3(2) under (6), + a ) ¥(3) under (7), 0,32 3(4) under (8), A, +(5) under (9), Fer +(3) under (10), sae) under (12): en 2(5) under (12), co 5(4) under (13), and aD 2(5) under (14), reversing the sign in every case. Then add up (6) to (9), placing under the sums of (7) to (9) their quotients divided by 2’(6). (7 Put the product ae +’(7) under (10), 76, 2’(8) under (11), 27) ¥6) 29) ends (12, mB, 2’(8) under (13), and re 2”(9) under (14), reversing each sign. yw itil Ds 1, Add (10) to (12), putting quotients ach and ech under the sums. - rig 2”(11 Put the product dy 2”(11) under (18) and m0) 2”(12) un- der (14), reversing the signs. MATHEMATICAL SECTION. - PHL wi 214 Add (13) and (14); when vrs =D. 2”(12 a ChE) Then, under (12), enter eee ae Fag? = ( > 9 Dx Dy le Next, under (9), enter 6) re ~ Ee = B. 20) | 3ta) 208) 22) Be) eat) pe ek Nores.—[1] The sign of summation is distinguished by an ad- ditional stroke for every additional quantity introduced under the column added up. [2] These additional quantities, under the columns of squares, (6), (10), and (13), will evidently all be negative. [3] This form may be extended to any number of unknown quantities, by insertion of ae, etc., between (4) and (5), be, etc., between (8) and (9), and so on. Modifications where there is a smaller number of unknown constants, and where one of them has the coefficient always unity, will be obvious. [4] One of the quantities a, }, etc., will, in many computations, be zero when another one is significant, and vice-versa ; as when one unknown quantity changes in the course of a series of observations. In this case we may save some columns by arranging our equation thus: a, A, + a, A, + 0B + etc. =y (where a, a, = 0, always). Here two sums are found under columns (1) to (5), two quotients under (2) to (5), and two additional quantities placed under each of the other columns before they are summed up. The remainder of the work then proceeds as before, except that the Jast step will be duplicate. [5] It will be found advisable always to make 4a, 2%, etc., as nearly zero as possible, so that the products will be smaller and there will be less danger of error. [6] The computation is to be checked by applying A, B, etc., and finding the residuals of y. Then 2 (a Ay), ¥(a 4b), etc., should all be zero. [7] Where but two unknown quantities are to be found, one of them with the constant coefficient unity (as A + b) B =), other methods will usually be preferable. Two of these will be given. I. If the values of 6 are symmetrical, so that b = 2? + b',,2+0’,, & + 0’,, etc., here all that is necessary to find B is to subtract the Lastly, under (5), enter D— B=. 152 PHILOSOPHICAL SOCIETY OF WASHINGTON: value of y for every # — b’ from that for #0’, to multiply the remainders by 0’, to find 2 (b’ay) and divide it by 2 5 (b”), when the quotient will be B. If A should be wanted also—as is very AY often not the case—then 2y must also be found, and A = = — 6B, where n equals the number of equations. If. In all cases we may obtain the required values by taking the difference of 6 and of y from the mean of the column, multiplying the residual by the former difference, thus forming columns of 2b\?2 rb » (0 _ =) and (0 _ =) (y _ a4 adding these and dividing the second sum by the first. That is, 210-FZ)0-2)} SY y |e ea iS Ue te 1 Wheit"A co =o) y (0 idl =) 1 ie {(@-= Ninto MEETING. DECEMBER 19, 1883. The Chairman presided. Sixteen members and guests present. Mr. H. Farquuar furnished a NOTE ON THE PROBLEM DISCUSSED BY MR. ALVORD, in which he showed that the volume of a spherical segment of height h, zi? (Rk — zh), being real for all values of h, both positive and negative, was to be interpreted for h<0 or h>2H as the vol- ume of the segment of the equilateral hyperboloid of two sheets whose axes equal #; this volume being taken with a negative sign. It was positive for negative values of hf, since it must become zero when h = 0 by negative increments; hence the minimum of the function when A = 0 in such problems as the ene discussed. Mr. Doo.itrLE read a communication on THE REJECTION OF DOUBTFUL OBSERVATIONS. ° [ Abstract. ] For the purposes of this discussion we may divide errors into ee, ee a MATHEMATICAL SECTION. 153 two‘grand classes, and name them, from their consequences, instruc- tive errors and uninstructive errors. The latter class includes blun- ders in recording, pointing on wrong objects, &c. The former con- sists of errors that indicate error in other observations. I once tried the experiment of dropping a short straight piece of wire five hundred times upon a sheet of ruled paper and counting the number of intersections of the wire with a ruled line. When the end of the wire touched or nearly touched a line, and inter- section was doubtful, I counted it as half an intersection. I re- corded the number of intersections in groups of fifty trials, as fol- lows: 23, 26, 28.5, 24, 31.5, 28, 27, 14, 25, 28.5. These numbers may be regarded as observations from which may be deduced the probable ratio of the length of the wire to the distance between two consecutive lines; and it seems impossible to account for the remarkable smallness of the eighth number by any supposition of uninstructive error. It is almost certain that a ratio deduced from it alone is largely in error; but it indicates that the other nine observations are somewhat in error, and that its error is needed to counterbalance theirs. If we retain it, and regard the mean of all as the most probable truth, we infer that this observation is 11.55 units in error. If we reject it, and take the mean of the other nine as the most probable truth, we infer that this observation is 12 5-6 units in error. It should be remembered that the rejection of an observation does not sweep from existence the fact of its occurrence; but merely increases its already large estimate of error. Because an error of 11.55 units is so large as to be very improbable, shall we therefore infer that an error of 12 5-6 units is more probable? It seems very clear to me that the larger an instructive error is the more instructive it is, and the more important is it that the observation containing it should not be rejected. The mean of all the ten above-described observations being regarded as the most probable truth, any one of the other nine could be better spared than the eighth. On the other hand, the larger an uninstructive error is, the more important it is that the observation should be rejected. Whenever an observation is intelligently rejected, there is a comparison of two antecedent probabilities, viz.: that of the occurrence of an instructive error of the magnitude involved and that of the occurrence of an uninstructive error of the same mag- nitude. When an error is evidently so large that it cannot possibly belong to the instructive class, the antecedent probability of such 14 154 PHILOSOPHICAL SOCIETY OF WASHINGTON. an instructive error is 0; the antecedent probability of an unin- structive error is always greater than 0; and the observation should certainly be rejected. But since the theory of least squares allows no limit whatever to the possible magnitude of instructive errors, such rejection involves the admission that the method of least squares is not applicable to the case. When an observation involves a merely suspicious error, which is neither so large that instructive- ness is impossible nor so small as to pass without question, it would seem reasonable that the observation should be weighted according to the relative magnitudes of the two antecedent probabilities which I have mentioned; but this can never be determined with any approach to mathematical precision. In order to make this matter clear, let us suppose for example that ninety-nine observations of equal weight and known to be free from uninstructive error are separately written on as many cards; that the number 25 is arbitrarily written on a similar card; that these hundred cards are thoroughly shuffled; and that ten cards being then drawn at random, the following numbers appear on them: 15, 18, 14, 25, 17, 16, 15, 18, 16, 17. Let it be required to determine from these data, according to the theory of least squares, the probability that the number 25 on the fourth card drawn is the record of an observation. Here the antecedent probability of an uninstructive error is by hypothesis equal to 1-10. I commence by assuming a value of the required probability, and weight the doubtful observation accordingly. I then proceed in the ordinary method and determine an approximation to the antecedent probability of the occurrence of a genuine observation giving the value 25 by integrating <= fe — © dt between the limits corresponding to 24.5 and 25.5, since the observations are taken to the nearest unit. This integral is the antecedent proba- bility of an instructive error of the given magnitude, tainted with the incorrectness of the assumption with which I began. Call this P to +P it agrees with my original assumption, the problem is solved. If it does not agree, I have data for a better assumption according to the well-known method of trial and error. After a few repetitions of the process, as I have found by experiment, an assumption can be made that will be verified by agreement with the result. integral p. Then is the resulting required probability. If MATHEMATICAL SECTION. 155 In practical problems the antecedent probability of blunders and other uninstructive errors is never known, and is only matter of exceedingly vague conjecture. Perhaps if a very large number of observations were examined, and the proportion of evidently unin- structive errors ascertained, a somewhat intelligent estimate might be made of the proportion of those that exist but are not evident; and data of some little value might be gathered toward a scientific method of weighting. But Ihave no faith that the result would be any where near worth the labor. At present, the best that a computer can do is to reject entirely, or retain entirely, or assign a simple weight, such as 3, 3, or #, in sheer desperation, and with the feeling that his judgment is nearly or quite worthless. It would be utter folly to assign weights upon a centesimal scale; and it would also be utter folly to conjecture an antecedent probability and proceed according to the method just set forth. It is well known that the method of least squares gives very un- trustworthy information in regard to the antecedent probability of large instructive errors. In regard to the other antecedent proba- bility required for an intelligent solution of the problem, it gives no information whatever. So far as I can understand Prof. Peirce’s method of arriving at a criterion, he takes two probabili- ties, both functions of probabilities of instructive error, and balances them against each other. This procedure reminds me of what sometimes haj.pens in war, when two detachments of the same army meet in the dark and fire into each other, each supposing the other to belong to the common enemy. Prof. Peirce also seems to me to violate the fundamental principle of the science of probabili- ties, that probabilities must be independent in order that their product shall equal concurrent probability. If a computer resorts to the criterion when he feels that his own judgment is worthless, and only then, the criterion is harmless ; since it is of no importance whether a decision is made by a worth. less judgment or a worthless criterion. In the discussion that followed, Mr. A. HAuu gave a brief account of the literature of the criteria which have been proposed for the rejection of doubtful observations. In addition to the criterion proposed by Prof. Peirce,,which had been discussed by Mr. Doolit- tle, that of Mr. E. J. Stone was mentioned; and also the proofs of a criterion given by Chauvenet and Watson. The advocacy of of Peirce’s criterion by Gould, Winlock, Bache, Coffin, and Schott 156 PHILOSOPHICAL SOCIETY OF WASHINGTON. was noticed, and also its criticism by Airy, Sténe, and Glaisher, together with Glaisher’s approval of De Morgan’s method of treating observations. In conclusion, Mr. HAut said: The general result of what has been done in this matter appears to be as as follows: Every one can devise a criterion that suits himself, but it will not please other people. Now there seems to be a good reason underlying this. The attempt to establish an arbitrary and general criterion for the dis- cussion and rejection of observations is an attempt to eliminate from this work the knowledge and judgment of the investigator. Such an attempt ought to fail, and it certainly will fail at length, no matter by what personal influence it may be supported. It is true that no proof has been given of the principle of the arith- metical mean for a finite number of observations, such as the prac- tical cases that always come before us; but we assume this principle as leading to the most probable result. When we depart from this principle, it must be done, I think, for reasons that are peculiar to each case, and there can be no better guide than the judgment of the investigator. It may be said that if the criteria that have been proposed be carefully managed they will do little harm, since the result of the arithmetical mean will be altered very little; and in fact this is their chief recommendation. But by diminishing the value of the real probable error the criteria give to the observ- ations a fictitious accuracy and a weight they do not deserve. The paper was also discussed by Messrs. Hit, Exuiorr, Far- QUHAR, WoopWARD, and others, including Mr. JAmMEs Maryn, a visitor—all agreeing, on essential points, with Mr. Doolittle’s view. Mr. R. S. WoopwAkrp then discussed THE SPECIAL TREATMENT OF CERTAIN FORMS OF OBSERVATION-EQUATIONS. [ Abstract. ] In a set of observation-equations whose type is z+ (t—t,) y—n =v with weight p, in which ¢, is an arbitrary constant, the same for éach equation, and in which the residuals, v, are supposed to arise solely from errors in the observed quantities, n, it will be best to make pea 2 MATHEMATICAL SECTION. 157 This value of ¢, makes the co-efficient of y in the first normal equation and the co-efficient of z, in the second normal equation, zero, and hence gives directly [pn] yornv a _ [pt —t,)n] ~ [pé—47] The weight of this value of x, is a maximum; 7. e., the value of pt] x, corresponding to ¢, = 7 P| has a greater weight than the value of x, corresponding to any other value of t,. The probable error of the function x, + yy is given by the simple formula. V ot wre, in which ¢,, and «, are the probable errors of x, and y, respectively. The investigation shows that, when several standards of length are to be intercompared two and two, in order to obtain the length of some one of them, it will be conducive to accuracy to have the mean temperatures of the several sets of comparisons equal. Remarks were made upon this communication by Mr. KuMMELL. Mr. Avex. S. CHRISTIE made a communication on CONTACT OF PLANE CURVES.* [ Abstract. ] Let 0 = fiz, y), 1), 0 = ¢(@, y), (2), and y = ¢(2), (8) be the equations of plane curves. Transferring the origin to (¢, 7), where = $(&), writing f, ¢ for f(§, 7), ¢(§, 7), respectively, and u, for 1 of 1 og dee? Yn for — I =e , we have y" o2 *o from (1), ae (ES iy 73 (oru,)), (1’), from (2), 2 3 30 a dy leap} oak 2(a'v,), (2'), and from (3), y= # z pty ge S| Br age + &e. ve * Throughout this paper, d, for lack of sorts, is put for round d, and denotes partial differentiation. 158 PHILOSOPHICAL SOCIETY OF WASHINGTON. Writing (8’) in the form y= zw, + 2’w, + aw, + &e. (3”) and assuming y” = 2”(y,) + c ay (¥,) + &e. (4) Where (»,) obviously equals w,”, and (,), (,), &., are functions v— y—l of &,7 to be determined, we have, from (4), vy ; _ =z vw) v2 t+ar.vt1.(4)+ae .»+2.(,)+ &e. (5) from (3”), = e®.1lwta'.2w,+2?.3w, + &e. | (6) d cae from (3”, 5),» y’. 2 =2"((,)yw,) +e (yew) y+1.u,) +2 (Gay +) ofl. uy +) 2 2.0) + &e. d ; < from (4,6), y”. - = 2(,) w, +2 fe (¢,)» . 2w, ot (,)y . 1w,)) se OES i Sey a ney att 1w,) + &e. " 0O=(%). »—-0.w+,).0-—1.y, 0=0,).2—0.u,+().¥—1.u,+0,).0—2.u, 0=6,).383—0.4,+().22—1.u,+ ©) .¥—-2.4, +(%).0—3.%, ° O=().m—0.u,4,+%).(m—1)¥—1.u, + (»,).(m — 2)» —2.w,—,+() . (m— 3) »— 38. u,_-, +...+(%,).0—m.u, 159 MATHEMATICAL SECTION. ee (TI—m)—a * in ({T—w) —9 ‘ (2) ‘n* (Z—wW) —«z° Sere fa +7 = (zg = Ww) ‘m*(Z—w)—a -°- im (g—w)— 9 °° ¢ "2" Z— «(e— w) ‘ c_my), * Z—4(F— w) oe) | ‘ ¢ ‘n° 1 —nz € m*T—a« ‘ mI —0 x “m*T—a(T—w) ‘t+ "n° QO— au u ~ "a —T—a(Z—w) * M*Q—A(T— wW) "n° T—a(@e—w) '-"n+ 9 —a(g—w) < in? 9 — ae © in 9 = 42 ‘ m*Q—« a % . ny —dARY OM DDTOY AA 160 PHILOSOPHICAL SOCIETY OF WASHINGTON. which determines the coefficients in (4). (*) Putting w,, for 1 é” Tie rs v+l rl, al, de Oy? We have yy gr * ¥ (atu) = 2 ((%) ty) +2 ((%) ty + (%) Uv) + & ces (CO) Uy + Oy) thy + (2) Mv) + &e., and this in (1’) gives an equation of the form 0=2A,+21A,+27A,+ 2A, + Ke. (8) viz: 0 = 2° [(0,) Mo} + 2 [(09) to + (01) Moo + (Lo) Mor] + 2° [ (0p) Ugo + (01) Myo + (Oz) Moo Ao) Mar + Ai) Mort (2) Mop] 4° [(0p) Usp + (01) May + (02) Myo + (95) Moo A Lo) Mort Ay) Mh + Ag) tor HF (20) he + C21) Moz + (8p) Mos] + Ke. (8’) for the abscissae of points common to (1) and (3). Similarly for the abscissae of points common to (2) and (3) we get an equation of the form 0O=2 Bote B, +7 B,+2 B, + &e. (9) viz: 0 = 2° [(O4) % J + 2 (00g) Mo + (1) Yo + Go) Mm] + &e. 8’) Let (2) contain at least p parameters, enabling us to pass (2) through p of the intersections of (1) with (8). When this is done we have the equation 0 = 2° (A,— B,) +. 2' (A, — B,) +2’ (A,—B,) + &c. (10) true for the p values of x corresponding to the p points common to (1), (2), (3). Let the » common points move to the origin, (10) must have p roots equal zero, that is, 0 = A, — B, 0= A, =— By, 0 = A, — B, . 2.0 = A,_, — Bo eee If we suppose (3) the parabolic representative of (1), 2 in (8) becomes indeterminate, and hence besides 0 = A, we have also C= A 0= A, Ge. that is, 0 ng with dy 6 [ = t+ Zt5, | va Ley a FS «Ae (ay ee 2.08" deatin Bide on, 2 NOs) On Oh ck AG Od 1d’ Of 1 dyof = 327 QaziP + Nae de, 1 Baeo, G2) 1 (2) 5 2 Bae ii Feet H(z oe | boa \ag) ago TBI de dB an? TBI Nae) oy L &e. &e. _ &e. * Putting x = 1 in (3/7) and (4), we obtain the multinomial theorem in the form (204 -+ Wy + Ws + &Ke.)¥ = (%) + (%) +e (%) + Ke. MATHEMATICAL SECTION. 161 I i: f equations fully determining ae : et : Ae , &c., in terms of the partial derivatives of f. Again, suppose (3) the parabolic representative of (2), then 0 = B,, with 0 = B,, 0 = B,, &c., and consequently by (11) 0 = A,, with O= A,,0=A,,...090=A,—,, or the first p—1 of the equations (12) are satisfied indifferently whether the = ; = re —1 aS therein contained be derived from (1) or (2); that is, we have arrived at Lagrange’s conditions for contact of the (p — 1) order, as a consequence of p - punctual contact; and it follows at once that the distance between two curves:in the neighborhood of ap - tuple common point is of the p™ order when the distance along the curves from the p- tuple point is of the 1st order.* Note. The abstracts of communications to the Mathematical Section have each been examined by a special committee, consisting of the Chairman, the Secretary, and a third member appointed by the Chairman. These third members were as follows: Title. Author. Third Member. Alignment Curves on any Surface___-- C. H. Kummeitt. A. S. CHRISTIE. The Mass of a Planet from Observa- tions of two Satellites__________- A HAGE: W. B. Tay or. Infinites and Infinitesimals____.---___ M. H. DoouitTLe. G. W. HILL. Planetary Perturbations of the Moon__G. W. HILL. EK. B. ELLIoTr. The Law of Error practically tested bys Larget-Shooting.. 2. =. 2-2. C. H. Kummett. A. S. CHRISTIE. Form of Least-Square Computation.__.H. FARQUHAR. R. S. WoopwarbD. Rejection of Doubtful Observations.._.M. H. DooLiItTLe. W. C. WINLOCK. Special Treatment of certain forms of Observation-Equations ----------R. S. Woopwarp. W. C. WINLOCK. Contact of Plane Curves _____..._____A. S. CHRISTIE. C. H. KUMMELL. * This paper will be continued. vy Pate a ' ' ts) LV oe Le he ae , Men ae Wan cata, iy BI ; ti ve if Pity thas RES et it Are ‘eat oF ) LPS PDR a EST LETS ae ’ . ‘ % « . \ fy ‘ i vesaul ae AY : ‘ hi 4 1 1a, sendy 2 , . * ' ; y 4 ys q 2 Par 4 , ‘¢ y v7 ? ; . ¢ CORRIGENDA, Vol. V, p. 86, line 2. For “ abused ”’ read absurd. es A, 6.7... Bor tens ” read earth. - ‘ ' e} b ‘ ' ‘ j » ie ry ' 6, . } : : ote v : . ‘ ; . ' ( : 1} ' by A : | r y ac ‘ ape! 4 , A FAP h i, f Phy 4 i saa ay a ! Pt Oe Ld delay . 1, iy ‘ eb i r is ’ t My ; ay Ra PAWL, Ge tt PY Dew Page, Abbe, Cleveland: communication on Deter- mining the temperature of the air......... 24 — —: report as Treasurel.......cccccccseeeeeeeees ripe. bl Address of the Chairman of the Mathemat- LES CCULON . sancccarscevocenscnaceradcupancanecesascenee — — — President.... Action of the International Geodetic Asso- ciation as to an initial meridian and uni- Versal time .......c0..eee00 Bich ceisecsescesacse nireseie Activital evolution... Agricultural college ratte, basebsveiscsueswcsncadvedacs 100 Ague, The conservative function of.............. 5 Air, Determining the temperature of the, 24, 46, 47 PICA GIACTATION 101 |. cccccenveccssssccersssoprssoeten SS —, Humidity of... SsunuedshansenasRavedasavee assess iO Alignment curves on any Saniece, with special application to the ellipsoid.......... Alvord, Benjamin: communication on a special case in maxima and minima....... 149 — —: remarks on agricultural college grants 106 123 — — — — glaciation in Alaska............0..008 . 35 — — — — Smithsonian funds invested in ARK ANESS DONS. ....s0ccesccsasesesoeee escpasneovnane 105 Analogues in z00-geoyraphy........seeceeeee rie 41 Announcement of death of B. F.Sands......... 41 — — — — O. H. Crane............ccessecceceeeee whem 4, — — — — Elisha Foote.......c...cce. cscceosceeeees . 48 — — — — Josiah Curtis 20.0... cece ceeeeeeeeees 41 — — — — LD. Gale... cece cccsseesceeeeo eens . 48 tirerle—ieen) ie ED, ULES. .csvscsevviecssccscconses cesses wih —-— election to membership of Albert BEMIS SS Pca bavdencyouciusscesss'sastesss) caavasecsess 14 —-_---- C. D. Walcott... —-—-- D. E. Salmon —----- E. C. Morgan —---- BL Ses UNE CSS -cutacvavacccesecesenr, 2S —-—---- TG OWA ci, scnespataasaae ye ---- J. H. Renshawe.......... 14 —---- J. M. Browne 111 --—--- ASOUBKINN ESN vascsccwesns 36 —--—- Re S. WOOGWArG vvccsesecccscoons 14 --—--- Set MIMI OM Gus eccencessnscessrss) (00 —--—--- SE ES OGISI Ge. crt es astascscsessce BAZO —--- MGs Chamberlin... .csseeteuee 100 —---- - Thomas Russell .. 10 —-—-—-_—— — W. C. EN 33 —----- W. T. Sampson.... 36 — — filling of vacant offices.............00sssccsses 41 — — invitation to Anthropological and Bio- POPICALSOCIObIOS..c0%:ssscesovsccasvazpedevsieonves 87, 98 Page. Announcement of new rules concerning pa- pers read before Sections..........cecseeseeaee . 38 — — organization of Mathematical Section.. 28 — — summer vacation.. ms) 09 Anthropic evolution...... Artultecsarecub ser) EVAL Antisell, Thomas: Gatien mone heakan Ha- WALA AS PULLS es cse teduanodssscohecucseskeacenenves 14 — —: remarks on meteorologic stations...... 47 — —: report of Auditing Committee............ 5 Aphapsis ........ “trenece evessbcibysnentbleserdsessevuencosce 133 Appalachian region, Geology of........ jackiegestes 31 Arithmetic, Binary ATKANSHS| DONCG ecacessecesssncntsecinviete dri ce ersesrass Articulation by the corfgenitally deaf... 76, 78, 84 Astronomy (see Mars, Perturbation, Saturn, Venus.) AtiTA@ TLOM say sesceaseucacsareesesess XXvViii, ¥xxii, xxxix Auditing Committee, Appointment of........... 111 — —, Report of............. Gareuseseerchesssanereaatanyvs a 8 Baker, Marcus: letter to Mathematical Sec- UL OM oes sepesescecedecerseccrseoyscatescceanseaenants asd ees . 122 Balfour memorial TunG)c.<.--..neseneose 36 Hydrometer determination of the specific GIAVIty Of SOLIGS......cceeeeeereeeceseeereeeserenee 26 Hygrometer observations.... 36 Hypothesis, Utility of, in science ........... xxxiii Ichthyological results of the voyage of the AIDAtrOSs ...ccosccscnssessccvsvcescsccnscecccsenscescanse 48 Idiots, Dumbness Of.......scesseeeereereereeeeeceeees Illinois, Loess hills of Inaugural address of the Chairman of the Mathematical Section. ..........-ccseseeseeeeeeees 117 Infinite and infinitesimal quantities ............ 133 Initial meridian, Universal...........sseesseeeessees 106 Intermarriage of deaf mutes............... 74, 76, 83 Intermittence Of VOICANOES......ceececeeeceeeeeereeee 91 International Geodetic Association ........--.+ 106 Invitation to Anthropological and Biological SOCTCHICS..v.cccsscvcccssancosseccoescccnsassasscnsesacess 87 Iowa, Loess of eastern........ socuenenseesde secre pmenne 92 Kerr, W. C.: communication On the geology of Hatteras and the neighboring coast.. 28 — — —, Election to membership Of.......+++++ 33 Kinematic hypothesis, The..........ss0+sesees xxviii King, A. F. A.: communication on The pre- vention of malarial diseases, illustrating, inter alia, the conservative function of AZUL... cccreceeernevner sushanSeavevacteconsnssnstenccsessen 5 Knox, J. J.: communication on The distri- bution of the surplus money of the United States among the States.............. Kotzebue Sound ice CLiffs.........seseseeeeee eucaes 34 Kummell, C. H.: communication on Align- PHILOSOPHICAL SOCIETY OF WASHINGTON. Page ment curves on any gurface, with spec- ial application to the ellipsoid................ 123 The theory of errors practi- cally tested by target shooting.......... sseee OS — — —: remarks on consequences of the re- lation of the circle to the equilateral hy- perbola... ade wsse isa devas Ugh —---- ‘infinitesimals..2.< ee 135 —-—--—- refinement in the determina- tion of the temperature of the air........... 26 Lavas of the Hawaiian Islands............++e+eeee 13 Lee, William: communication entitled Sketches from medallic medical history 39 Leadville Ore CepOSits......sceccsssecesee seceeessnees 32 Least-Square COMPUtAtiON .........ceseeceeereeren ere 150 Lefavour, E. B.: remarks on infinitesimals... 135 Liagre’s theory.............c.ccsssenasasevssusnnshmseenseaen 139 List Of members :cessesastscceseacceesuasnaaee Ae sy Loess of eastern Iowa 93 Longitudes, Unification Of ........ccereceeseeeee cone LOG McCullough, Hugh: remarks on money de- posited by the United States with the State of Im diam ars ciictsscacttscescesetendeawemecee 106 McDowell, Silas: cited on thermal belts of North) Carolinas: 22s. sccccocneeceeeceaahepueane 11, 12 McGee, W J: communication on The drain- age system and the distribution of the loess of eastern TOWa.........csceeesecees pececets 93 Malarial diseases, Prevention Of...........0.ss00+ 5 Mallery, Garrick: election as Vice-president 41 Mallet's theory of volCanisM..........sssceeeeeeeees 90 Marriage of deaf mutes... oss cheap pee Mass of planets, Deteiiinstias ats asa es crt, » 132 Mathematical Section, Address by Chair- AVIAN OL; LHC secseneessaccsuctersuccsaewaee wabuseihae 117 — —, Bulletin of the..........cecccceeeseee acta 113, 121 — —, Committee of the.... —, Members of the.... — —, Officers of the....... na — —, Organization Of the........0.....sccccseses 28, 121 — =, Rules Of....sssccosccctivencseser aeeneaea +. 11551385 * Mathematics (see Arithmetic, Formulas, Math- ematical Section.).....0. acaceudedes Seine bRaaneetern Matter, Combination of..............04 Maxima and minima........ Medallic medical history.. Members, List of. : — of the Mathematical Section.............2.0000+ Meridian, Universal initial............... iecanaeee Metamorphic deposits....... pags seesensnenscsecreonecs Metamorphism and subsidence ........-.c.0se0e Meteorology (see Climate, Humidity, Hygro- meter, Temperature, Thermal, Thermome- ter.) INDEX. 167 Page Page. Metric system discussed......ccc.cccccsecseeeee essere 4 | Riley, C. V., Election of, as member of the Minerals, Separation of, by density...... nawiaeda 26 General Com miitheescencc.sesecssccs afuocesesrvese 41 Mad es/Of MOtION seaiaiisessecavcssdse-secuere aad RMT #| Hines of Saturn. secs st. bay tesa coe tes 41 Moon’s motion, Pertubations of the.............. 136 | Rules for the publication of the Bulletin sucess xiii Morgan, E. C., Election to membership of ... 87 | —, New, on papers read before section......... 38 Mosquito, Inoculation by the........csseeeeeeeeeeee 7 | —, Standing, of the General Committee....... xii Motion, Modes Oftsccccisccccecsnccccccdennes + XXxvili, xli | — — — — Mathematical Section.................. 115 Munroe, C. E.: communication on the De- termination of the specific gravity of solids by the common hydrometer......... 26 Mutes, Fallacies concerning.............. aeavauy 49, 78 Natural language ............. SShceeccoareecee 64, 70, '75, 79 VAG, LG, Of) MALLOY sss cccssccccteatesvodcevenssstece 5 Nebular hypothesis and volcanic eruption... 87 — — not discredited by Saturnian and Mar- IPPON OO See ciegcucuscacusceccsuscaspectsrs cueactioneste North Carolina, Geology of.... Es Thormal belts Of ......cesresscscssosees Notation, New arithmetic................ccesseeeeee- Note on the rings of Saturn............. eesaneausess aed Observation-equations..............sssseeseeseteeceeees 156 Observations, Rejection of doubtful.............. 152 Officers of the Mathematical Section ...... 28, 122 Seeaimeesvom—= OCT OGY vcsconscexees sussue evseccssconsecsenas xiv, XV Ore deposition by replacement..............seeee 32 Peat beds of North Carolina.............csssssesssees RIAD SMS ic svacaisovess avcics casbccsenakcatsvicsee. Periods, Saturnian............. EBEPOLU Al CalON GAT. ccccsasscesdecacersecesvavesesseotsce Pertubations, LUNAL...........ccssesesssesrseresensnes Physical evolution........ pewakosseavine- Wicaeestecacsres xliii BAIOEUT ONAN SUAGE cass alecestossccreosonseccscseceve snes . 84 Porter, Sarah: cited on the use of signs by deaf-mute children 81 Powell, J. W.: address as President XXV —-—-—: remarks on the drainage system SEP OMSTONIM, LGW soxcasasebocsecen-ic ostceteslaeoaseate 97 —--—-—-—— loess of western IIlinois..... 97 —_--- volcanic eruption................ 92, 93 President’s annual addresg,,............0..ccesesees XXV Prevention of malarial disease............ssecee00 5 IPEOOTUNOUGs TN Oscccck secs ccsecaconccvesocesstecdesiecsesce 123 Quasi general differentiation, A....... diseenascencs 122 Recent experiments on serpent venom........ 38 Rejection of doubtful observations.............. 152 Renshawe, J. H., Election (o membership of, 14 Replacement in ore deposition Report of the Treasurer................ Response, The, of terrestrial climate to ya- riations in solar radiation.......0....cceesces 10 Ficlets SRP pee ee eee mae ng ix Russell, Thomas, Election to membership of, 10 Salmon, D. E., Election to membership of.... 111 Sampson, W. T. , Election to membership of, 36 Sands, B. F., Death Ofmisatatescveasercenees : 41 Saturn’s rings 41 “Science” to report the scientific proceed- INES Of the Society eyo ete ncccvceeeeek. 5, 122 Seismographic record obtained in Japan...... 38 Shelters for thermometers.........ccsesscssceceoeee 46 Sibscota, George : cited on the cause of dumb- DOSS) sccsJencnssncsee sonsanhoveccetedseshasdeavessuccacstorers 49 Sign language of the deaf...... 63, 66, 71, 75, 79, 84 Sketches from medallic medical history...... 39 Skinner, J. O., Election to membership of.... 36 Smith, Edwin: communication on a Seismo- graphic record obtained in Japan.......... 87 Smithsonian investment .........cccccsssssceesaceres 105 Solar radiation in its relation to climate ...... 10 Sound velocity as a measure of air tempera- CULE sressispacctanehsussersntscdivessessstcuecsensnteeecit 47 Speech and thouphit.cacs ccscssecsseseccsssceussce 53, 81 — reading by the eye............ 56, 60, 70, 76, 78, 84 Special case, A, in maxima and minima....... 149 — treatment of certain forms of observation- BQUALIONS soca .iicensasssusaceeecelcasrs asacveseseicessoce 156 Specific gravities, Determination of.............. 26 Standard time.. a Scneerbwccbeseenansacesrect OG Standing rules (See Bake. Substance, matter, motion, and force............ 14 Surplus money, Distribution of ..............s000 103 Survival of the fittest, not the law of an- thropic evolution ..............cccccseeeeses xl vii, lii Taylor, W. B.: communication entitled Note On tite TINS OL SAUUTNss.cesses ceessecest sees cotics 41 — — —: remarks on binary arithmetic........ 4 —-—- designation of apsides............ 133 --— eT MNEICO SIMA Sy eacevsucsseoneccasess.ce LOD -- thermometric obseryation...... 47 War ret Shootin. ctagvasessuecdack easckesseeesenec eee 139 Temperature of the air..................002. 24, 46, 47 The theory of errors practically tested by CALE Ob SHOOBING: oso ca.ccc-cuccwccaccesascaeonascearte 138 The thermal belts of North Carolina............ 11 Thermometer CXpOSure...........0.ccccccceccecees 24, 26 Mhourht and speeches vsssotuecrete eee 53, 81 Three methods, The, of evolution............. xxvii Topographical indications of a fault near Harpor's OLTy scc.cecscetaseetivesece ecdscccseeses 30 ee 168 Page Transit of Venus..........0.+ seupnysb Wey speeeiaessmetnpent 21 Treasurer’s annual report...........ecereseereeeeees xxij — accounts for 1882, Report of Auditing COMMIttSe ON the......diecscccovcccedevaccssncsves 5 Unification of longitudes and time.............+. 106 Units of force and energy, including electric units Universal time.... Velocity of sound as a measure of air tem- PEVRUUTEG \. cvess,sier sete edsa0e6 47 Venus, Transit of. 21 Volcanic problem, The, stated.........sccsccsseseee 87 Walcott, C. D.: communication on The Cam- brian system in the United States and PHILOSOPHICAL SOCIETY OF WASHINGTON. Page Cop Sey: oF talus eee anes MMR. cctl Eh ees 98 — — —, Election to membership Of............. 48 Walling, H. F.: communication on Topo- graphical indications of a fault near Har- PON'S POLTY: .iocssecasscacessadonseesbapnastsnueadnaeene 30 — — —, Election to membership of............ 14 Ward, L. F.: remarks on Dismal Swamp...... 30 Water, a factor in voleanie eruption.............. 87 White, C. A.: remarks on the drainage sys- teams iOf Towa so.scosvanests| cneepevescsetrabdauensanadsatnd-sncecna-sucesahe teseaaddu-ae 1871, Mar. 13 Bates, Henry Hobatrt...........seeseeeeree Patent Office. The Portland.............. 1871, Nov. 4 Bean, Tarleton Hoffman..............+++. National Museum. 1411 R. I. Ave...... 1884, Apr. 26 Beardslee, Lester Anthony (@)........ Captain U. 8. N., Navy Department....| 1875, Feb. 27 Bell, Alexander Graham.. v.....ccsese0 Scott Circle. 1500 R. I. Ave.....sssseceees- 1879, Mar. 29 Bell, Chichester Alexander............. TOBM OONWWAW Ga. 20 s-ccsncunonpeakesuvecenenacers 1881, Oct. 8 Benér, STEPHEN VINCENT.......cc0cce00 Ordnance Office, War Department. | 1871, Mar.13 1717 I St. N. W. ISASSCLS PESING screen ssnsscvve sssaesinasessce ai Seuiebagaian Institution. 1444 N St. | 1875, Jan. 16 BILLINGS, JOHN SHAW......+.ssceesseseceenes press leeod Office, U.S. A. 3027 N | 1871, Mar. 13 Birney; William... .cccc..csesssconcssscense 456 Louisiana Ave. 1901 Harewood | 1879, Mar. 29 Ave., Le Droit Park. Birnie, Rogers: (@)....c0s.sceccosssscccnsecse Cold Spring, Putnam Co., N. Y........00 1876, Mar. 11 Blair, Henry IW SVI10i(C) setacnsccsenssnctss| ssseacnsatosnscnvsceebscvenesevancnvesscsehnansasssenudedved 1884, Feh. 2 Bodfish, Sumner Homer...e.ccsseseseseee Geological Survey. 605 F St. N. W.....| 1888, Mar. 24 Boutelle, CHATICSIOCIS icc ccssseseueccesencs Coast and Geodetic Survey Office. 1884, Feb. 16 1513 20th St. N. W. Bowles, Francis Tiffany...........sseses 1823 Jefferson PlACOniccc, .sosseccascaseubennay 1884, Mar. 29 Brown, Stimson Joseph .........20ee0004 *| Naval Observatory. 2133 K St. N.W... 1884, Apr. 12 Browne, John Mills .............cs000..0e0. ceo Director, U.S.N. The Port- | 1883, Novy. 24 and. ; Burchard, Horatio Chapin .............. Director of the Mint. Riggs House...! 1879, May 10 Ve LIST OF MEMBERS. XVII DaTE OF NAME. P. O. ADDRESS AND RESIDENCE. inuneeran: Burgess, Edward Sandford............. High School. 81012th St. N. W......+.. 1883, Mar. 24 Burnett, Swan MOSES......ccsseceeeeesereee AUD isto NW cawaetessecess| xewese sevesesecscesee] 1879, Mar. 29 Busey, Samuel Clagett .......sseeeeee POD UISU UN Wet. -wet es ccsncelacGgasess Parr 1874, Jan. 17 CAPRON, HORACE......0..seeeseeeees evene cantar MRMOREOrEB BU tenes scien tstcceet mas attce eases 1871, Mar. 13 Case, Augustus Ludlow (@)..........+. Bristol, R. I......... ieete Grr eroeeecr erEenn etch 1872, Nov. 16 Casey, THOMAS LINCOLN....ccsso-cseecceeee aes Cores of Engineers. 1419 K St. | 1871, Mar. 13 IN. . Caziare, Louis Vasmer (@)........++- -..| War Department.......... meuacutaecabenaetencd 1882, Feb. 25 CHASE, SALMON PORTLAND (G).......00-- [ecccsersccessencscen sense eneees 1871, Mar. 13 Chamberlin, Thomas Crowderv......... Geological Survey........... 1883, Mar. 24 Chickering, John White, Jr... ..-.| Deaf Mute College, Kends 1874, Apr 11 Christie, Alexander Smyth............. Coast and Geodetic Survey Office. | 1880, Dec. 4 628 Mass. Ave. N. W. Clapp, William Henry (@)........eeccsee Ft. Davis, Tex. 1416 Corcoran St. | 1882, Feb. 25 Washington. QOlarikk, HGWard oc -cc.ccsvscssseccosuss paehers Or ree Office, Capitol. 417 4th | 1877, Feb. 24 Clark, Ezra Westcote..............+0 eeeees Revenue Marine Bureau, Treasury | 1882, Mor. 25 Department. Woodley Road. Clarke, Frank Wigglesworth........... Geological Survey. 1425 Q St. N. W...] 1874, Apr. 11 Corrin, JouN Hunrineron ORANE...... LOOISDIS GIN Ea Wiet uatesstteces conc teers ...| 1871, Mar. 13 ABGUIAS EE REO OLLCI: ((3)),.- 5 -scbencsscdccceost! Ustenspevtwecteneapeabenescesscnsene 1879, Oct. 21 Comstock, John Henry (@).........0008 Cornell University, Ithaca, N. Y......... 1880, Feb. 14 Coues, Elliott..............cc0e-es Smithsonian Inst. 1726 N. St. N. W...| 1874, Jan. 17 RATA MESENTAMEN, HA NEULL ()scsee serves [asccse seocvep terre rec ncnetecescocasesccbudcsdbesats cased 1871, Mar. 13 Craigs, RODELE......ccccase-ee-rene Army Signal Office. 1008 I St. N. W...] 1873, Jan. 4 Craig, THOMAS ()........2..ccccseseeeserres Johns Hopkins Uniy., Baltimore, Md..| 1879, Nov. 22 Crane, CHARLES HENRY (d).......00.20008 eee acute a be hcedes secuuscspyevedesaacsethecm ieee 1871, Mar. 13 Curtis, George Edwatrd..........ecsese Army Signal Office. 1416 Corcoran St..| 1884, Jan. 5 Curtis, Josiah (d)........ Rote meab ar ecobel| Wibecassrasauemubasetere sys Cee M eas cae aviszsouuieeckuanven 1874, Mar. 28 Cutts, Richard Dominicus (d)..... saps! ten -@eshaapusesivedacconanegceadsvatuurisstetrsysassececceen 1871, Apr. 29 Dah, WILLIAM HEALEY ....c0.sescesseosens Care Smithsonian Institution. 1119 | 1871, Mar. 13 12th St. N. W. Davis, Charles Henry ().........ccseseee[ee addins saewdauadtann:sacarses- en panceaalabestidsdedecsaet 1874, Jan. 17 Davis, Charles Henry..........ccssessseee ae eee aceite 1705 Rhode Island | 1880, June 19 ve. N. W. Dean, Richard Orain (@)......cessecesees Naval Hospital, New York............ce.0. 1872, Apr. 23 De Caindry, William Augustin........ Commissary General’s Office. 924 | 1881, Apr. 30 19th St. N. W. De Land, Theodore Louis............0+ Treasury Dept. 126 7th St. N. E......... 1880, Dee. 18 Dewey, Frederick Perkins..............) National Museum. 1007 G St. N. W.....] 1884, Apr. 25 NOVO OOLGONT icc shenecescas cstess sanstucsnebenspanesnucsiue strech epan cautndueeniecste ...| 1871, Mar. 13 Peirce, Charles Sanders (@)..........00 Coast and Geodetic Survey Office....... 1873, Mar. 1 Pilling, James Constantine.............. Geological Survey. 918 M St. N. W..] 1881, Feb. 19 Poe, Orlando Metcalfe (@)..........see00 34 Congress St. West, Detroit, Mich...] 1873, Oct. 4 Poindexter, William Mundy........... 701 15th St. N. W. 806 17th St. N. W..| 1884, Dee. 20 Pope, Benjamin Franklin ............... Surgeon General’s Office, U. S. A. | 1882, Dea. 16 1309 20th St. N. W. Porter, David: Dixon()i...ceccsensce couse | teeavoatesbesdecer wescchets dusts cess suesccacuuesssereneeeery 1874, Apr. 11 Powell, John Wesley.......... ahseeveestee Geological Survey. 910 M St. N .| 1874, Jan. 17 Prentiss, Daniel Webster.......... cpacagd 1224 9th St. N. W.. ..| 1880, Jan. 3 Pritchett, Henry Smith (q)..............) Washington University, St. “Louis, Mo. 1879, Mar. 29 Rathbone, Henry. Reed (@) i. .. >=" purty wo souvleg ee ae eo [POL --£,o0g sv ‘dxo ‘y10qi19 “yO -----==-goq1uel ‘eT Mey “A “VW "7 stojuprd ‘roTOaNjoqy 3 x» ppue “--- “quopIselg “SUITIO AA ‘OL Soe 9 ‘reqnbaey “EL ~-L0ag sv -dxo “touTLD “WO 10 IF ” v8 00 8% ” ” 00 OST 00 d0cg'std ‘oproagogy p ppar ASST itoyiuvl ‘te_MBy “AW ‘svar, sv ‘dxo ‘eqqy puvpeas[p Za ‘TopTOMIOCT 9 ppne ” ‘W94TL) “SE “OD rN 209 sv sosuodxo ‘aeqnbaey “A ‘pred uoya og, “SHUN LIGNAIXY =p | ano | ra NI od HID DO OO AS CO) 2 Selig jo) S) a) iS AV "AQ “F88L ‘0% 29g Sumpua unali ay2 vol ‘waunsnany, ‘aqqy punjaaayy yzun zunovon ua Uopburysnyy fo hgavoog yoorydosojnyd a4J, "ud "Pe ' 7 it \ BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON, ANNUAL ADDRESS OF THE PRESIDENT. XXVII fei M Fe es Mv ANNUAL ADDRESS OF THE PRESIDENT, JAMES C. WELLING. Delivered December 6, 1884. THE ATOMIC PHILOSOPHY, PHYSICAL AND META- _ PHYSICAL. Every nation under the sun has a philosophy of some kind, but the philosophy we profess draws the lines of its historic traditions, if not its “increasing purpose,” from the home of our Aryan an- cestors in Greece. It was here that the typical forms of our litera- ture were invented, that the art of sculpture was carried to its climax, and that the architecture of the lintel came to a transfigu- ration in the Theseum and the Parthenon. And as if all these glories were not enough, it is the further good fortune of the Greeks to have at least opened up the great leading problems of human enquiry, in physics, in psychology, and in ethics; and to have so opened them up at the starting point of the world’s Torch- race, that the light shed on these questions more than twenty-five centuries ago is still a matter of curious retrospection to this generation of ours on whom the ends of the world are come. It is to one of the oldest of the formal physical philosophies ever framed by the mind of man for the explanation of the mechanical structure of the Universe that I purpose to call your attention to- night—a theory the most comprehensive in its scope, and, at the same time, the most searching in its subtility, which has been handed down to us by all antiquity—a theory which in its ingenuity represents the synthetic power of the Greek mind at the highest stage of its physical speculation—a theory which the literature of Rome has preserved in the amber of Cicero’s philosophical disquisition, and embalmed in the immortal verse of Lucretius—a theory, in fine, which has survived the old dialectic in which it was first conceived, because it has come to a new birth in the forms of modern science. I refer to what is known in history as the Atomic Philosophy of the Greeks. p.@.G 0. ¢ XXX PHILOSOPHICAL SOCIETY OF WASHINGTON. The fundamental principle of the ancient physical philosophy— its point of departure and its ever re-entering point of return—is found in the famous well-worn maxim of metaphysics, that out of nothing nothing comes, and that what 7s can never be annihilated. It was in the name of this maxim and under the shadow of its authority that the Greek physical philosophers sought to shelter their whole right of free enquiry from the charge of impiety, and if to us the dictum seems the merest truism, it was not so regarded at the dawn of natural philosophy. Sometimes used as a logical club with which to brain a stolid and incurious indifferentism, and sometimes waved as a red flag in the face of polytheistic supersti- tion, it meets us perpetually in all the oldest records of ancient philosophical speculation—in the formal elaborations of Aristotle,* in the lucubrations of Boéthius,} and in the verse of poets as remote from each other in style and creed as Lucretius, the lively Epicu- rean,{ and Persius, the sternest of Stoic moralists.§ This maxim stirred the philosophical mind of antiquity to its lowest depth, because it was then the type and symbol of a whole method of phi- losophizing—a method regarded by many as not a little presump- tuous, much as the Copernican theory of the Universe was regarded in the sixteenth century, or much as the Formula of Evolution is regarded to-day outside of scientific circles. It was because the maxim seemed to so many the challenge of a vain wisdom and of a false philosophy that the early champions of physical philosophy sometimes felt themselves called to vindicate the truth of this truism by an appeal to formal argument. The necessity for such an appeal measures the scientific ineptitude of the average mind at that early age. ‘“ If what emerges into sensible perception,” argues Epicurus with the utmost gravity, “can be con- ceived as coming from nothing, then everything might come of any- thing, and that, too, without any need of germs; and if what dis- appears from sensible perception was really destroyed into nothing, then all things might perish without anything being left into which * Aristotle: De Generatione et Corruptione, I, iii, 5, (Didot’s ed., vol. 2, p: 437.) + Boéthius: De Consolatione Philosophie, Lib. V, Prosa 1. } Lucretius: De Rerum Natura, I, 161-227. 2 Persius: Sativa, iii, 84. ANNUAL ADDRESS OF THE PRESIDENT. XXXI sk they were resolved.” * Such was the rude flint-flake with which, as their only weapon of logic, the early Nimrods of philosophy in Greece defended their right to philosophize in the paleolithic stage of natural enquiry. As the next step in this metaphysical logic we find a distinction drawn by the ancient Greek philosophers between things as they are in substrate and things as they appear, disappear, and reappear in time—between the noumenal and the phenomenal world, as we would say to-day in the Kantian phraseology. It was the favorite doctrine of the Eleatic school of philosophers that we get a true conception of things only when, abstracting from their individ- uality, their partitiveness and their changing forms, we find the ultimate root and unity of all being in a simple, indivisible, and unchangeable substrate, which is the true object of knowledge, be- cause it is the true basis of all reality. This concept increased in clearness as it passed through the minds of Xenophanes, Parmeni- des, and Empedocles, until, in the generalizations of the last-named philosopher, the ultimate substrate of things was resolved into four elementary substances—earth, air, fire, and water; each uncreated and imperishable, each equal in quantity, each composed, within itself, of parts that are qualitatively the same, and each forever in- commutable with the others; yet each and all capable of every variety and degree of mixture in the manifold combinations of things as they appear in the sensible world. On the other hand, it was held by Heraclitus that this funda- mental substrate or unity of things is a mere figment of the phil- osophical imagination, and that it is only as things are conceived to be in perpetual flux that the forms of our knowledge can be brought into correspondence with the forms of actual being. That is, to the doctrine of the unchanging substrate of things Heraclitus opposed the doctrine of the perpetual flux of things. It remained to effect a synthesis and reconciliation between these opposing views of the Eleatic and Heraclitic philosophies of nature, while at the same time saving the fundamental dogma of all natural philosophizing, that out of nothing nothing comes. Such a basis of pacification was found in the terms of the Atomic Philosophy, in the doctrine that the changing forms, positions, motions, and phases of * Diog. Laért.: Lives of the Philosophers, swb voce ‘‘ Epicurus.”’ XXXIT PHILOSOPHICAL SOCIETY OF WASHINGTON. things are to be conceived as a perpetual flux, resulting from the changing permutations and combinations of the indestructible atoms composing the eternal substrate of nature. And ‘thus it was that the doctrine of ultimate atoms, incessantly modified in the forms of their combination, but remaining forever the same in substance, became the legitimate deduction and the crowning corollary of the primal eldest maxim of physical philosophy. Aristotle expressly gives this genesis of the Atomic Philosophy of Greece in its reduc- tion by Anaxagoras. After saying that Anaxagoras hypothesized an infinity of atoms, to explain the myriad varieties of nature, be- cause he wished to avoid the reproach of getting something out of nothing, Aristotle adds: “ From the fact that contraries are made out of each other, they must needs have previously existed in each other ; for if everything that becomes must needs come either from some- thing or from nothing, and if this latter alternative is impossible, (about which all who treat of nature are agreed in opinion,) then it only remains to infer that everything which becomes must have come from the things in which it pre-existed, though, on account of the smallness of their bulks, made out of things imperceptible to us.” * The Atomic Philosophy of the Greeks was, therefore, not a mere exhalation of the imagination, but a logical inference from the starting point and major premise of their natural metaphysics. The doctrine of ultimate atoms in nature was, indeed, the necessary com- plement and reconciliation of the conception that all things are in elemental stir, and that yet in this elemental stir there is no crea- tion of anything out of nothing and no annihilation of anything, but only composition, decomposition, and recomposition. It need not surprise us, therefore, to find that the doctrine of ultimate atoms in nature is a universal- form of thought among thinking men of all the most advanced races in antiquity. Into the hidden historic springs of the Atomic Philosophy, as formu- lated by the Greeks, it is not here proposed to enquire. Whether its * Aristotle: Naturalis Auscultatio, I, iv, 2, (Didot’s ed., vol. 2, p. 252.) Compare, also, Lucretius, De Rer. Nat., I, 543-545: —— ‘ Quoniam supra docui nil posse creari ‘De nilo, neque quod genitum est ad nil revocari, Esse immortali primordia corpore debent.”’ = ANNUAL ADDRESS OF THE PRESIDENT. XXXIII germs were derived from Egypt, or from India, or from Pheenicia, or whether it was an original birth of the Hellenic mind, is a mat- ter of curious historic interest which hardly admits, perhaps, of precise and positive determination, though certain it is that India had an Atomic Philosophy before the Greeks. However possible or probable it may be that the early Greek philosophers borrowed some of their lore under this head, as we know they did under others, from the Egyptian priests; or whatever truth there may be in the tradition, reported by Posidonius,* (Cicero’s teacher in phi- losophy,) that one Moschus, a Phcenician, imparted the doctrine to Pythagoras, it is very certain that the Greek philosophers have made the doctrine their own by the logical development they gave to it, and by the hereditament in it which they have bequeathed to © the subsequent generations of men moving along the lines of human progress. It has been more than suspected that the doctrine dates in Greece from the age of Pythagoras, by reason of certain spe- cific ideas, which we can read in the spectrum analysis of the most distant times by the light of modern anthropological science. Cer- tain definite lines of thought are to be found in the psychology of every epoch, and these lines betray the mental constitution of the epoch as surely as the vapors of the elements absorb rays of the same refrangibilities that they radiate. In the days of Pythago- ras we discover certain psychical ideas which are seen to have been the natural reflex of the great fundamental dogma out of which the Atomic Philosophy sprang. I refer to the doctrine of metempsychosis and of its correlate, the pre-existence of souls. If it be assumed that the human soul is something generically different from the body, and is not generated by it, then it necessa- rily follows, according to the maxim De nihilo nihil fit, that the - soul pre-existed somewhere before the atoms of the body were put together, and from the other branch of the maxim, that it must continue to exist somewhere after the body is dissolved. The doc- trine of the transmigration of souls is not, therefore, a mere vagary of the ethnical imagination, but the natural offspring of that form of Pythagorean dualism which distinguished the soul, as not only generically, but genetically distinct from the body. Hence, the *Strabo: Geog., Lib. xv1. Cf. Sextus Empiricus: Adversus Mathematicos, Lib. 9, 17 XXXIV PHILOSOPHICAL SOCIETY OF WASHINGTON. doctrine reappears under one form or another in every dualistic conception of matter and mind—now in the purple light of Plato’s imperial fancy, and now in the pallid shades of that metaphysical theology which, in the days of Origen and St. Augustine, arrayed the doctors of the Church into opposing schools on the great ques- tion of Traducianism or Creationism. In whatever way the Atomic Philosophy was begotten in’ the Greek mind, we know that on its emergence it was subjected to the solvents of philosophical criticism, and underwent a variety of transformations. So soon as we come within the lines of definite history we find a bifurcation of ideas between such typical teachers as Anaxagoras on the one hand, and Leucippus and Democritus on the other. This dissidence of opinions had regard to the nature and the constitution of the ultimate atoms which compose the substance of matter. The doctrine of Anaxagoras was qualitative; the doctrine of Democritus was quantitative. Anaxagoras held that the atoms which compose the physical Uni- verse in its fleeting forms, and at the same time in its enduring substance, are eternally differentiated in kinds, and that it was by the collocation and adhesion of like parts—of bony atoms to make bone, of fleshy atoms to make flesh, of stony atoms to make stones —that the actual varieties of body in the Universe were built up. This is the famous doctrine of Homeomeria which fares so ill in the spiritual philosophy of Plato, and which fares no better in the materialistic philosophy of Lucretius. Aristotle tells us that Anaxagoras was driven to adopt this hypothesis in order to relieve the doctrine of atoms at the points where the heaviest stress and tightest pinch seemed to be laid upon it by the dogma De nthilo nihil fit; for how else, said Anaxagoras, could we account for the existing varieties of matter unless there be an original and eternal variety in its constituent elements? Democritus simplified the theory of atoms by giving to it a purely mechanical reduction. Conceiving atoms to be invisible by reason of their smallness, he at the same time conceived them to be indi- visible, not as mathematically considered, but as physically consid- ered; and while holding them to be infinite in number and infinite in their-shapes, he at the same time held that they differed not at all in inherent quality, but simply in their shapes, sizes,,situations, and motions, and that hence it was by the different combination of ANNUAL ADDRESS OF THE PRESIDENT. XXXV atoms differing in these mechanical aspects that all the varieties of bodies and souls were integrated, disintegrated, and reintegrated. * The different impressions produced on the human senses by differ- ent bodies, according to their various mechanical constitutions, were regarded by him as purely subjective—the mechanical results of different concussions made on the senses by the different effluxes of things,t and, therefore, no more requiring any qualitative differ- ences to explain the phenomena of sensation than to explain the phenomena of being. Weight and hardness were treated by De- mocritus as primary qualities of bodies resulting from the greater or less degrees in which their constituent atoms are compacted, as compared with the interstitial voids or vacua. The secondary qualities of bodies are simply the impressions they make on the human senses, depending, as has just been said, on the varying shapes, sizes, and arrangements of the atoms composing all the varieties of material substance. Anaxagoras had made his theory of atoms a pendant to dualism, conceiving, as he did, that souls, both animal and rational, are eter- nally pre-existent before the birth, and post-existent after the disso- lution, of the bodies in which they temporarily resided. { Democ- ritus made the animal soul and the rational soul only two more dis- tinct varieties in the mechanical collocation of atoms varying in shape, size, situation, and motion; and, therefore, he had no place in his theory for the transmigration of souls considered as entities distinct from bodies. Souls and bodies were equally the results of a concourse of atoms obeying in their movements the law of a me- chanical necessity. That is, to the dualism which preceded him Democritus opposed a pure and simple monism. Yet between the materialism of Democritus and the dualism of Anaxagoras there is not much to choose; for the misty spiritualism of the latter did not * Aristotle: De Generat. et Corrup., I, i, 4, (Didot’s ed., vol. 2, p. 482;) also Arist.: Metaphysics, VII, ii, 2, (Didot’s ed., vol. 2, p. 559,) and the Nat. Auscul., I, v, 1, (Didot’s ed., vol. 2, p. 254.) t Action from a distance, as of the magnet on iron, was also explained by Democritus on the hypothesis of ‘‘effluxes.”” Zeller: Philosophieder Griechen, Erster Theil, p. 704. { Cudworth: Intellectual System of the Universe, vol. I, chap. 1, (Andover ed,) p. 95. : XXXVI PHILOSOPHICAL SOCIETY OF WASHINGTON. carry with it any clear conception of personal identity, and hence Lucretius justly argued that the doctrine of a future life, as held by many in his day, was stripped of all significance if the chain of personal consciousness is broken at death.* And to this fundamental antithesis of ideas lying at the bottom of these two forms of the Greek Atomic Philosophy another anti- thesis must be added in the Stratonical Hylozoism, which, assuming in matter an atomic structure partly material and partly vital, pro- ceeded to account for the genesis of animated bodies on the super- added assumption of a plastic energy working in nature to the pro- duction of every living thing. In a word, Strato’s matter, instinct with life, and waiting only for the first chance to be stuck together in the composition of plants and animals, seems to have been the metaphysical anticipation of our modern protoplasm.f ? It was in opposition alike to the physics of Anaxagoras, Democ- ritus, and Strato, that Plato reared his splendid fabric of idealism, while Aristotle, for his part, rejected the philosophy of atoms alto- gether, and installed in its place for centuries the doctrine of Form and Quality, and Substance and Entelechy, whatever that may mean. “Tf,” he says, “there be no other substance beyond the substances existing in nature, then Physics is the first science; but if there be a certain substance which is immoyable, then this is before body, and Philosophy is the first science.” | That single sentence re- capitulates the whole verbal philosophy of the Middle Ages. Plato was so hostile to the hypothesis of Democritus that he never once names that philosopher in all his writings, though it is the Abderite physicist to whom he intends a disparaging allusion when in the Timeus he impales on the shafts of his irony “a certain philosopher of an indefinite and ignorant mind.” Aristotle names him often enough, either separately or in conjunction with Leucippus, and treats the Atomic Philosophy with respect as an ‘invention framed to explain the transformation and birth of things—explaining birth and dissolution by the decomposition and recomposition of atoms, * Lucret.: De Rerum Natura, Lib. iii, 851. + Cicero aptly defines the antithesis of ideas between Democritus and Strato. Sce Academ. Prior., Lib. II, xxxviii, 121. Also, De Nat. Deor., Lib. I, xiii, 35. { Arist.: Bet, Lipe'V 1; 0% ef. Dib.) X, ‘vil, 9: ANNUAL ADDRESS OF THE PRESIDENT. XXXVII and explaining transformations by the arrangement and position of atoms.” * . But it is in the physical philosophy of Epicurus, as that philo- sophy has been expounded and expanded by Lucretius, that we can discover the fullest and clearest exposition of the doctrine of atoms, considered as a key to the structure of the Universe. We here have the doctrine formulated into a theodicy of naturism, a theory of psychology, a cosmogony, and an anthropology. According to Epicurus, in his Lucretian rendering, atoms are minute material particles, indivisible, not by reason of their smallness, but of their solidity which makes them indestructible and unchangeable in their constitution ; they have size, weight, and shape, yet are forever in- visible to the eye; in shape, some of the atoms are different from the others, but, while the number of the different shapes is finite, the number of atoms of each shape is infinite; every atom must have at least three cacumina (yovias), that is, infinitesimally small bounding points which are incapable of existing apart from the atom, but must be conceived to coexist with it in order to give definition to it and to enclose its “solid singleness;” some of the atoms are hook-shaped, some only slightly jagged, some smooth, &c.; atoms are in incessant motion, racing through space in all directions under the stress of their weight, according to the fa- voring conditions of a vacuum more or less complete, yet so that the sum of their motions results in the supreme repose of gross matter, except when a thing exhibits the motion of translation in space—a form of motion which is molar and not atomic; atoms move besides at an enormous uniform speed, in parallel lines, up and down, so far as there can be any up and down in a universe equally boundless in all directions, and except so far as some of the atoms have originally a shape which makes them capable of slight deflections from parallel straight lines—that elinamen principiorum which was invented by Epicurus to explain the phenomena of so- * Arist.: De Generat. et Corrup., I, ii, 4 (Didot’s ed., vol. 2, p. 484.) t Epicurus derived the motion of atoms from their weight, which gives movement i7 vacuo. Democritus derived the motion of atoms from an im- pulse given to them in the beginning. So says Cicero (De Fato, 20, 46), but for the contrary opinion, ¢f. Zeller: Philos. der Griechen, Erster Theil, 702, 714. XX XVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. called voluntary motion in animals and free-will in men, while at the same time explaining how it is that this free-will is eternally encased in the rigid parallel lines of the other atoms. In this way Epicurus supposed himself to have added a useful supplementary hypothesis to the original hypothesis of Democritus, who binding nature fast in fate had not left free the human will, because he had omitted to provide for that third mode of motion in atoms which is required to explain the possibility and genesis of voluntary mo- tion and self determination. Such is a brief and imperfect exposition of the Atomic Philoso- phy of the Greeks—a form of physical speculation the most elabo- rate, the most ingenious, and, to use a Latinism of Dr. Johnson, the most concinnous which has come down to us from all antiquity. The Epicurean physics are as much superior to the Aristotelian and the Stoical physics as the ethics of the Lyceum and of the Porch are superior to the ethics of the Sty; and yet it now remains to be said that in all this operose system of metaphysico-physical atoms there is not an atom of scientific truth, in the modern sense of that word. The whole speculation is a mirage, caused by unequal refractions in the Greek intellect—by the volatility of the Greek fancy passing through a dense, practical ignorance with regard to everything but surface views in nature. Or, to borrow one of Plato’s favorite figures, it was a “ wind-egg,” begotten of metaphysic con- ceit, and differing from the other “wind-eggs” of that time in the greater symmetry of its shell rather than in the greater fecundation of its contents. It had the form, but not the power of scientific truth. If there be such a thing as atoms they must needs be chem- ical conceptions, and the very word “ chemistry” had not yet come into the Greek language, because the rationale of such a science had not even dawned on the horizon of the Greek intellect by the faintest reflection from below. Much explanation, which does not explain, has been wasted to account for the incapacity of the Greek mind in physical philosophy. The learned historian of the Inductive Sciences, Dr. William Whewell, ascribes this incapacity to the alleged fact that though this sprightly race had in their possession an abundance of facts, and were acute observers and critics, their ideas “ were not distinct and appropriate to the facts.”* It would * William Whewell: History of the Inductive Sciences, vol. I, p. 87. ANNUAL ADDRESS OF THE PRESIDENT. XXXIX hardly be possible to frame an explanation more pointless. If there has ever been a hypothesis framed with more “distinct ideas” than that of the Greek atomists, I am not acquainted with it, and it is precisely because it was so “appropriate” to the surface facts of the Greek observation that it was so illusory. It was fitted to these facts with a concinnitas that is most admirable from a psychological point of view. It was invented to fit them, and its whole raison d’étre was that it did fit them, so far as ideas and words could make it fit. For this purpose it was revised, modified, contracted, en- larged, supplemented, until it seemed to fit every sinuosity of the facts of nature, as far as the facts of nature were open to the appre- hension of the Greeks in the 5th century before Christ. The hy- pothesis was strong just where it seems weak to Dr. Whewell, and it is precisely because it was so ideally strong that it was so physic- ally weak, and it is precisely because it fitted the facts so well that it was a delusion andasnare. Men rested in it with a sense of satisfac- tion which simulated the rest of a mind turning on the poles of truth. It satisfied the highest cravings of Greek physical enquiry in the then contemporaneous stage of mental evolution in Greece. The Greek mind of that age had not reached a stage of development which required anything more than metaphysical hypotheses for the explanation of physical facts, because it had not reached a stage of evolution which capacitated it to frame hypotheses in physics capa- ble of anything more than metaphysical verification. And hence it was in the ingenuity of a plausible hypothesis, and in the nicety with which it fitted the superficial facts that the subtle and artistic mind of the Greeks found the sole interest and zest which a physi- cal hypothesis had for them or could have. “Ancient logic,” says Prof. Jowett, “was always mistaking the truth of the form for the truth of the matter.”* The conscious incapacity of the Greeks for physical science was so great that we find the best class of minds among them absolutely revolting at the very idea of such a science. Socrates, for instance, had no patience with it. Plato represents him in the Phedo as at the same time deploring misology—the hatred of formal ideas—and yet, in almost the same breath, confess- ing himself a misologist in the presence of mechanical conceptions of nature. He liked the doctrines of Anaxagoras well enough, so * Jowett’s Plato, vol. I, p. 376. XL PHILOSOPHICAL SOCIETY OF WASHINGTON. far as they moved in mind, but he detested them, to use the words put in his mouth by Plato, so far as they moved in “air, and ether, and water, and such like inconsequences ;” * and, detesting them, he falls back upon a purely anthropomorphic conception of the Uni- verse—anthropomorphic because it is avowedly anthropocentric, with Socrates for its centre. The whole passage is a most instruct- ive page in comparative psychology, now that we can read it in the light of modern anthropological science. It is no part of my present purpose to carry the history of the Atomic Philosophy into Roman speculation. The Romans took all their ideas in mental, moral, and physical philosophy at second-hand from the Greeks.f Strong in the practical arts of war and polity, they were content to be in literature imitators and in philosophy eclectics. Equally inept for the deft metaphysical analysis of the Greeks and for their fine artistic synthesis, the Romans none the less contributed, on the practical side of life, to the definite exposi- tion of the contents of all the philosophical systems of the Greeks. Hence we could ill spare the ponderous banter of Cicero when he mocks at the weak points of the Atomic Philosophy, and still less could we spare that reasoned elaboration of its strong points which has made the De Rerum Natura of Lucretius the most systematic, the most complete, the most earnest, and the most realistic of all the reductions which the Atomic Philosophy has ever received. But after allowing for all his skill in the episodical handling of the rival systems of Heraclitus, Empedocles, and Anaxagoras, for his power of description, for the vivacity of his narrative, for the force and often the beauty of his illustrations and analogies, it must still be conceded that there is much more of original poetry than of original philosophy in these glowing hexameters of the Epicurean philoso- pher-poet. In a history of the Atomic Philosophy we can leap the chasm of the Middle Ages at a single bound. The physical philosophers of * Phedo, 347; Jowett’s Plato, vol. I, p. 427. { For evidence as to the imbecility of the Roman mind in physical phi- losophy, see the 2nd Book of Cicero’s ‘‘ Prior Academics,’’ which is a long wail over the want of truth, or of tests of truth, in physical speculation. tDe Natura Deorum, I, 18, 54, 66, 69, 73, 120; ef. De Fate, I, x, xi, xx; De Finibus, I, vi--vii; Tuse. Disput. I, xi, 22; xviii, 42. ANNUAL ADDRESS OF THE PRESIDENT. XLI that time were not discussing the concourse of atoms, fortuitous or otherwise, but were carefully pondering, with Doctors Divine and Angclical, Subtile and Irrefragable, the difference between Ens and Essentia, between materia quomodolibet accepta and materia signata, between quidditas per se and hecceitas per se, between ultima entitas entis and ultima actualitas forme. As we plod our weary way through the Quodlibeta of these venerable doctors, we can but envy the angels one of the faculties ascribed to them by St. Thomas Aquinas—that of being able to pass from point to point without passing through intermediate spaces. Bacon,* as he stood at the threshold of the new dispensation of physical science, had made a plea for the forgotten philosophy of Democritus, but when the metaphysical philosophy of Europe came to a new Avatar in the brain of Descartes, we find that thinker denying a discrete conception of matter, and arguing for the con- trary conception of continuous extension, of the identification of extension with substance, and, hence, of the infinite divisi- bility of matter. He says: “It is easy to demonstrate that there cannot be atoms; that is, parts of bodies or of matter which are of an indivisible nature, as some philosophers have imagined, since, however small we may suppose these parts, inasmuch as they must needs have extension, we conceive that there is not one of them which cannot still be divided into two or more still smaller parts; whence it follows that it is divisible.” | It will here be seen that Descartes falls into a confusion of ideas with regard to the atoms of the ancient philosophers. They did not conceive that the atom was indivisible because of its smallness, but because of the indestructible solidity which made it incapable of being cut, or broken, or bent, and which also made it impervious to heat or hu- midity. { *See, especially, Cogitationes de Natura Rerum, and De Principiis atque Originibus, &e. Works, (Ellis & Spedding’s ed., London,) vol. III, pp. 15, 82, et seq.; cf. Advancement of Learning, Book II, vii, 7, (Ellis & Sped- ding’s ed.,) vol. ITI, p. 358. } For a formal criticism on Democritus’ theory of atoms see Principes de la Philosophie, Cfuvres de Descartes, (Cousin,) tome III, p. 516, and cf. Aristotle: De Generatione et Corruptione, I, ii, 11-21, where this criticism is anticipated and surpassed. $‘‘ Corpora individua propter soliditatem,’’ Cic., De Fin., I, vi, 17; ef. Lucret., I, lines 532-5. XLII PHILOSOPHICAL SOCIETY OF WASHINGTON. And this supposed conflict between the infinite divisibility of matter, mathematically considered, and the actual ihdivisibility of atoms, physically considered, is a pure logomachy resulting from what the lawyers would call a misjoinder of parties and a misjoinder of issues. The mathematician, contending for the infinite divisi- bility of matter, proceeds from the idea of space to a fact in nature, while the atomist, contending for the actual indivisibility of the atom, proceeds from an assumed fact in nature to the idea of space, - and so, as has been said, the duellists cross swords in the air over the head of a phantom standing between them, and never succeed in touching each other.* From this time onward, for many years, the opinions of philoso- phers concerning the nature or reality of atoms seem to have floated in a state of uncertainty between the views of the ancients and the views of Descartes. For instance, we find Henry More, the platonizing metaphysician of England, in the 17th century, adventuring the following dogmatic definition of matter: “I have taken the boldness to assert that matter consists of indiscerptible parts, understanding by indiscerptible parts particles that have, indeed, real extension, but so little that they cannot have less and be anything at all, and, therefore, cannot be actually divided. The parts that constitute an indiscerptible part are real, but divisible only intellectually, it being of the very essence of whatever is to have parts or extension in some measure or other, for, to take away all extension is to reduce a thing only to a mathematical point.” For the physical atom of Greek metaphysics, Leibnitz, itis known, substituted the monad or formal atom, considered as the continent and complex of an infinite number of essences. Leibnitz tells us that so soon as he had thrown off the yoke of Aristotle he plunged into the vacuum and atomic hurly-burly of Democritus, but that he could find no rest there, because he could not account for the gene- sis of mind in man on any mechanical theory of purely physical atoms. Hence the invention of the Leibnitzian Monadology and Pre-established Harmony—a form of metaphysical philosophizing which reflects the mental evolution and intellectual environment *See Westminster Review, vol. 59, p. 178, cf. Samuel Brown: Lectures on the Atomic Theory, Edinburgh, 1858. + Quoted in Munro’s Lucretius, vol. 2, p. 158. . ANNUAL ADDRESS OF THE PRESIDENT. XLIII of the 17th century, as exactly as the metaphysical speculations of Anaxagoras and Democritus and Epicurus represent the mental evolution and intellectual environment of the Greeks two thousand years before. The atom of Leibnitz instead of being an indivisible and sempiternal “solid singleness”’ is a created monad, a “manu- factured article,” deriving its perpetuity and power from the im- manent and perpetual “fulgurations of Divinity.”* It is the curious destiny of the atomic philosophy, let me here say, in paren- thesis, that it has subtended three very distinct orders of meta-_ physic—the polytheistic metaphysic of Greece and Rome, the theistic metaphysic of the Renaissance period, and the scientific metaphysic of our own day. According to Leibnitz separate classes of monads have separate qualities. Different degrees of aggregation in monads, differing in kind, make the varieties of matter. The natural mutations of monads proceed from an intestine force which is the principle or change in matter. In all simple substance there is a plurality of relations and affections, so that a residuum of relations and affec- tions remains after every transfer of affections and relations in the production of material changes. These material changes proceed according to the law of continuity, for all change of the created monad is only the modulus of its perdurancy.| The monad is inconceivable, except as a creation of Divinity. When created, it is destructible only by the decree of Omnipotence.t Monads work no changes in each other’s inner constitution, and therefore act on each other according to a Divine Pre-established Harmony, which makes each monad the mirror of the Universe, and the con- tinuous register of all physical changes, past, present, and future. Hence the order of the movement and the continuity of the pro- cess which have resulted in the formation of the only world pos- sible and the best world possible. It will be seen that we are here *« Dieu seul est Vunité primitive ou la substance simple originaire, dont toutes les monades créées ou dérivatives sont des productions, et naissent, pour ainsi dire, par des fulgurations continuelles de la Divinité, de moment & mo- ment.”? (Monadologie, prin. 47). Leib. : Opera Phil., Lat. Gal. Germ. om- nia. Berlin, 1840, p. 708. } Leibnitii Principia Philosophie, More Geometrico demonstrata, p. 38. jt Ibid., pp. 71, 74. XLIV PHILOSOPHICAL SOCIETY OF WASHINGTON. far enough away from the Epicurean atoms, but we are still work- ing with the atoms of pure metaphysics. ° It is equally in accordance with the chronological order of time, and the logical order of scientific ideas, that we should next turn to Newton. And of Newton, the greatest name in all physical philosophy, it need only be said that in his work on Optics he re- turned to a conception of atoms, which, except that it proceeds on the assumption of a Deity and of final cause, is substantially identi- cal with that of Leucippus, Democritus, and Epicurus. He says: “All these things considered [that is, the chemical facts he had just recited], it seems probable to me that God in the beginning formed matter in solid, massy, hard, impenetrable, movable parti- cles, of such sizes and figures, and with such other properties and in such proportion to space as most conduced to the end for which He formed them; and that these primitive particles, being solids, are incomparably harder than any porous bodies compounded,of them, even so very hard as never to wear or break in pieces—no ordinary power being able to divide what God himself made one in the first creation.” This definition reminds us of Lucretius. In continuation Newton adds: “ While the particles continue entire they may compose bodies of one and the same nature and texture in all ages; but should they wear away or break in pieces, the nature of things depending on them would be changed. Water and earth composed of old worn particles would not be of the same nature and texture now with water and earth composed of entire particles in the beginning. And, therefore, that nature may be lasting, the changes of corporeal things are to be placed only in the various separations and new associations, and motions of these permanent particles.” The very form of this last-cited statement carries us back to the cradle of the Atomic Philosophy.* But it is not so much the form of Newton’s statement which excites our admiration as the connection of thought in which it stands. The whole of * Anpdzpttos 03 xar Asdutrxog momjoaytss ta oyypata, THY Adhotwow nar chy yéveow & tobtwy motodat, Oraxptozt yey zat ovyxplost yéveow zat giopdy, taZ2¢ OF zat Hose adhoiwor. Aristotle: Izy: Tsvecsws zat Phopas, 1, 2,4. (CDidot’s ed., vol. 2., p. 454.) ANNUAL ADDRESS OF THE PRESIDENT. XLV the “3st Query,” under which this passage occurs in the book of | “‘Opticks,”’ is occupied with certain chemical analyses which Newton had made in his laboratory. Newton, we know, was an alchemist, and spent laborious days and nights in trying to discover the secret by which base metals might be rendered noble; but I can hardly concur with Prof. Jevons when he says that Newton’s “lofty powers of deductive investigation were wholly useless” in the conduct of these experiments.* There is some gold at the bottom of even his alchemical crucible. He was the first to put the conception of atoms in their rightful logical connection with the phenomena of practical chemistry. It would here be in order to follow Joseph Boscovich in his pro- found theory of the constitution of matter, if in doing so we might not fall into the danger of drifting too far from the atom considered as a minim of corporeal singleness. With him the atom is a point of attractive and repulsive forces rather than an ultimate physical element; and as it was really the atom of chemical physics which Democritus posited in his mind without knowing it, thus setting ap the altar of science to an “unknown god,” it is time that we should hasten towards the epoch when Chemistry came to rend the vail from the face of this Isis whom the Greek atomists had so long and so ignorantly worshipped. It is in the writings of the Hon. Robert Boyle, pleasantly de- scribed by his Irish biographer, with a somewhat Irish collocation of ideas, as “ Father of Chemistry and brother of the Earl of Cork,” that we find the period of transition, when the old order of meta- physical atoms is changing to give place to the new order of physical atoms as weighed and measured by modern chemistry. In his essay on “ The Intestine Motions of the Particles of Quiescent Bodies,” } as also in his essays on Fluidity and Firmness, he threw out some positive ideas on the old atomic philosophy. He sup- poses it to be of Phcenician derivation, and even tries to effect a reconciliation between that philosophy and the Cartesian notion of continuous substance by drawing on the maieria subtilis of the French philosopher (which was conceived to pass constantly, like a *Jevons: Principles of Science, vol. II, p. 188. t Opticks, Book III, Query 31. t Robert Boyle’s Works, vol. I, p. 444. XLVI PHILOSOPHICAL SOCIETY OF WASHINGTON. stream, through the pores of the solidest matter) as a very good analagon for the racing atoms of Epicurus. : It is, however, in his essay entitled an “Attempt to make chemi- ical experiments useful to illustrate the notions of the corpuscular philosophy,” * that he approaches this discussion with a bold front. He there says: “ The corpuscular doctrine, rejecting the substantial forms of the schools, and making bodies to differ but in magnitude, figure, motion, or rest, and situation of their component particles, which may be always infinitely varied, seems much more favorable to the chemical doctrine of the possibility of working wonderful changes and even transformations in mixed bodies. . . . As many chemical experiments may be happily explicated by the cor- puscularian notions, so many of the corpuscularian notions may be commodiously either illustrated or confirmed by chemical experi- ments.” + It will be seen at once, in the very dialect and purport of such language, that we have reached, even in Boyle, a turning point of ,the whole Atomic Philosophy. His words import that we are to use “the corpuscularian notions” to explicate chemical experiments, and that, in turn, the corpuscularian notions may find a new and solid basis in chemical experimentation. Men have changed their whole Welt-Anschauung, as compared with that of the Greeks in the days of Epicurus, before such processes of thought and such instruments or methods of enquiry become possible. It is only as the thoughts of men are widened with the process of the suns that they take in, or can take in, those wider horizons and deeper vistas of truth which are opened to the human mind by the ascending hierarchies of the physical sciences. We have now passed the border-line which separates the metaphysico-physical atoms of Epi- curus from the physico-metaphysical atoms of modern chemical science. I can afford to pass over this part of my story sicco pede, for we shall henceforth have to deal only with the atoms required by the hypotheses of positive and experimental science to explain the actual facts and processes of nature, not as those facts and processes lie on the surface of things, but as extorted from the very bosom * Robert Boyle’s Works, vol. I, p. 354. f Ibid., pp. 358, 359. ANNUAL ADDRESS OF THE PRESIDENT. XLVII of nature by the racks and thumbscrews of physical enquiry. In- stead of taking our atoms as they were distilled and attenuated by the refining brains of an Anaxagoras, a Democritus, an Epicurus, or a Leibnitz, we can now take them as weighed and measured by the quantitative, qualitative, or volumetric analysis of modern chemistry, in ways that Anaxagoras or Democritus or Epicurus or Leibnitz never dreamed of in their philosophy. The distance between the 5th century before Christ and the year 1800 is meas- ured as well by John Dalton as by John Howard. John Dalton and John Howard would have each been impossible in the days of Democritus—the one as much so as the other. John Howard plunged into the reek of European prisons at the impulse of a Christian philanthropy unknown to the Greek, with all his love of the Good, the Beautiful, and the True. John Dalton plunged into the reek of the Lancashire marshes,” at the impulse of an abstract science unknown to the Greek with all his love of dialectics, of art, and of xsthetic culture. John Howard, to use the fine phrase of Burke, taught men who love mercy to “ take the gauge and dimen- sion” of human misery. John Dalton taught men who love truth in disinterested studies to take the gauge and dimension of the ele- ments which compose the physical Universe. Who was this John Dalton that stands in such typical relation with the scientific thought of our century? Given, a man “meditative and ratiocinative;” a meteorologist, curious in all eudiometrical research, and, therefore, perpetually experimenting on the constitution of mixed gases; a teacher of arithmetic, so given to mental numeration that on his first visit to London he counts all the carriages he sees while wending his way to the Friends’ Meeting House on a Sunday; a chemist, who took the diffusion and absorption of elastic fluids as his special province of investigation; a theorist, who never theorized without an exper- iment, and an experimenter who never experimented without a theory, and you have John Dalton, the father and founder = the Modern Atomic Philosophy. As early as the year 1802, in some experimental combinations of oxygen with nitrous gas, Dalton discovered that “the elements of oxygen combined with a certain portion of nitrous gas, or with twice that portion, but with no intermediate quantity.” Though he 9 * He obtained his inflammable gas from these marshes. XLVIITI PHILOSOPHICAL SOCIETY OF WASHINGTON. called attention at the time to “the theory of the process,” he does not seem to have apprehended the generality of the principle of definite and multiple proportions till a few years later, when the doctrine dawned on him in the course of some investigations into the constitution of olefiant gas and carburetted hydrogen gas.* Richter, before him, had ascertained the quantity of any base required to saturate one hundred measures of sulphuric acid, and had formed a table exhibiting the proportions of the acids and alkaline bases constituting neutral] salts, but Dalton took this table and translated it into the relative weights of the ultimate atoms composing these saline compounds. The doctrine of atomic weights had thus already become a work- ing hypothesis in chemistry, no longer an idle speculation, and we soon find Berzelius writing to Dalton that “multiple proportions are a mystery without it.” { From this time onward the history of chemistry has been studded with fresh confirmations of the new atomic logic, while ever and anon prophetic glints of truth, implicit in every true physical hypothesis, have leaped into the light of ocular demonstration with each advancing stage in chemical science. Time would fail to tell the beads of the atomic rosary. The doctrine of fixed, multiple, and volumetric combinations, as formulated by Avo- gadro in 1813;§ the determination of the proportions in which bodies combine according to the number and disposition respect- ively of their molecules, as announced by Ampére in 1814, with special reference to the clear-cut distinction between molecules and their integrant atoms, (already presaged before Ampére by Laurent and Gerhardt;) || the relation between the atomic weights of bodies and their specific heats, conjectured by Dalton and estab- lished by Dulong and Petit in 1819;9] the law of isomorphism, an- nounced by Mitscherlich at the close of the same year, from which it appeared that “a similar atomic constitution determines not only *Henry: Memoirs of the Life and Scientific Researches of John Dalton, p- 80. + Ibid., p. 85. t Ibid., p. 100. 2 Wurtz: The Atomic Theory, p. 36. || Annales de Chimie, vol. 90, p. 48. q Wurtz: The Atomic Theory, p. 52. ANNUAL ADDRESS OF THE PRESIDENT. XLIX the analogy of chemical properties, but also the similarity of physi- cal forms;”* the discoveries in electrolysis, with their bearing on atomicity, as published by Faraday in 1834, in the Seventh Series or his Experimental Researches ; + the labors of Berzelius in clarify- ing the atomic weights of the elements; the “law of Octavyes,” an- nounced by Newlands in 1865, according to which the elements were divided into groups, having numbers differing by seven, or some multiple of seven ;{ the enlarged Periodic System of the elements, as published by Mendelejeff in 1869, with the prognostication of undiscovered metals required to make the system complete—among them a metal which the Russian chemist proceeded to namé “ekaalu- minium” in advance of its discovery ;§ the discovery of the missing metal in 1875, by Lecoq de Boisbaudran, who found it in a blende from the mines of Pierrefitte, in the Pyrenees, and gave to it the name of “Gallium,” without knowing that he had lighted on the “missing link” of Mendelejeff; || the extension of this periodic system by Lothar Meyer, with his Curve of the Elements, showing that the ductility, fusibility, and volatility of bodies are functions of their comparative atomic weights; the periodic system, as re- vised and extended during this very year, by Prof. Carnelley, in the light of the experimental boiling and melting points and heats of formation of the halogen compounds of the elements,§] (chlorides, bromides, and iodides;) Carnelley’s tables of color relations in chemical compounds as indicating the influence of atomic weights ;** and, lastly, Carnelley’s new reduction of the periodic system of the elements considered in the light of their occurrence in nature, with the helpful inferences to be drawn from it ***—these, and such like discoveries as these, following in the wake of the modern atomic -* Experimental Researches in Electricity, vol. I, pp. 230-258. + Wurtz: The Atomic Theory, p. 58. t+ Newlands: The Discovery of the Periodic Law, &c., p. 14. 3 Annalen der Chemie und Pharmacie, Supplement Band 8, p. 133 et seq. || Comptes Rendus, t. LX X XI, p. 493. How fully Mendelejeff recognized in gallium the characters wanted to fill the gap in his periodic system, see Comptes Rendus, same volume, p. 969. {| Philosophical Magazine for July, 1884. ** Phil. Mag. for August, 1884. *** Phil. Mag. for September, 1884 18 L PHILOSOPHICAL SOCIETY OF WASHINGTON. theory, have abundantly vindicated its value as an instrument of chemical research, while conspiring to vindicate its truth by giving to its votaries that ability of prediction which is the crucial test of science. The theory, besides, has sometimes “snatched a grace beyond the reach of art” by working retroactively to the purifica- tion of chemical method from errors and defects incident to the most careful manipulations of the practical chemist. Standing in the presence of chemical science, as now constituted, Baron Liebig has expressed the opinion that we can scarcely con- ceive how it could have been developed without the Daltonian hypothesis. And yet the atom of Dalton, considered in its rela- tion to our natural senses, is just as incapable of visible and tangi- ble demonstration as the atom of Democritus. For this reason it is known that Faraday could never fully reconcile himself to the modern doctrine of atoms.* But, in fact, there is a genetic and a generic difference between the ancient and the modern conception. The former is the offspring of the philosophical imagination toying with analogy. The latter is the offspring of the philosophi- cal imagination gendering with the homologies of reason. The atom of Democritus sprang into thought under the plastic forms by which he figured to himself at will the invisible relations and constitution of matter. The atom of Dalton sprang into thought from a rigid mathematical mind figuring to itself certain de- terminate relations which had become visible in elastic fluids. The atom of Democritus was, by the terms of its genesis, incapable of verification. The atom of Dalton was, by the terms of its genesis, capable of verification, if true, in all the gases of nature. Metaphysic thought born of the analogical reason can never con- clusively prove its legitimacy. Metaphysic thought born of the - homological reason can always prove its legitimacy, and, until it does, has no rights of heirship in the kingdom of science. The essential quality of a metaphysico-physical hypothesis is that it should be plausible; the essential quality of a physico-metaphysical hypothesis is that itshould be apodictic. The former is “magistral and peremptory;” the latter is “ingenuous and faithful.” The former is contrived in such sort as to be “soonest believed,” the * Faraday: Experimental Researches in Electricity, vol. 2, p. 284. But ef. vol. I, p. 249. . ANNUAL ADDRESS OF THE PRESIDENT. LI latter is contrived in such sort as to be “easiliest examined,” to cite the words of Bacon.* The Atomic Philosophy may, therefore, be said to offer a good type of all that is valid in physical metaphysics, and of all that is invalid in metaphysical physics. As the child in the infantile stage of his development dwells delightedly amid fays and talismans, because his metaphysic is stronger than his physics, so the savage man, artless child of nature, is easily pleased with the rattle of some lying legend, or tickled with the straw of some preposterous myth—the more preposterous the better. A cultivated race whose imagination is creative and artistic, but whose reason has not yet been developed by the processes of a rigorous logic, will demand, as has been already said, an artful and curious felicity in their physical theories—but they will demand nothing more, be- cause when this demand is met, their highest. intellectual demand has been met. It isnot until “the heir of all the ages” has learned to change the organon and method of his physical enquiries, and to put his reason over his imagination, by making imagination the hand-maid of reason, that Science is born. Long before this stage has been reached the children of Science may come to the birth, but there is not strength to deliver, because the true maieutic of science— experimentation with rational hypothesis, and rational hypothesis with experimentation—has not yet come to the teeming mind of philosophy. The goddess Experimentation is the Lucina of Science. The free surrender of all metaphysical conceptions to the hands of this Lucina, with the distinct knowledge that she will strangle them if they are not well formed, is the birth-pang of the scientific spirit. Until this stage of mental evolution is reached we shall have as many theories of the Universe as we have stages of culture, for every stage of culture will have a physics of its own, because it has a metaphysic of its own. Hence, the endless varieties of cosmol- ogy—the Hottentot physics, the Indian physics, the Stoical physics, the Epicurean physics, the Leibnitzian physics, the Cartesian phys- ics, and such like—all the coinage of the metaphysical imagination. Grote enumerates as many as twelve distinct physical philosophies which divided speculative opinion in Greece during the century and a half between Thales and the Peloponnesian war. * The Advancement of Learning, Book I, v, 9. LII PHILOSOPHICAL SOCIETY OF WASHINGTON. It is the mission of science to bring the physics of the world into unity by reading the phenomena of the world in the dry light of reason, and by continuing to spell and parse the hieroglyphs of Nature until the rational processes of our logic are brought into demonstrated correspondence with the actual processes of Nature. Science still keeps metaphysic in her service. But instead of weaving whole fabrics from the metaphysical loom and devising ingenious tissues which only reveal the nakedness of reason, Science in passing from the known to the unknown employs metaphysic as the gossamer spider employs the single thread on which she sways and balances her movements between two solid points. The thread is tied to something solid as the condition of reaching some- thing solid after her aerial flight. So the man of science, work- ing in and under the limitations of physics, works on the lines of metaphysic thought when he frames the tentative hypotheses with which he returns again to the patient, practical study of nature.* The scientific man reads the Universe backward by the inductive syllogism, because Nature has proceeded forward in her evolutions, according to an unbroken chain of antecedent causes. The physi- cal Universe is indeed a fasciculus of natural syllogisms colligated into the compactest unity, and so holding all things, forces, and functions under the bonds of logic. The scientific man, at any given stage of his enquiry, has before him only the conclusions or at best only the minor premises and the conclusions of this world- process. And he knows that these conclusions of the natural syllo- gistic process have been reached through a perpetual flux in the universal complex of things, forces, and functions—a flux which dates from the beginning of star-mist and nebula, or from the beginning of that more elementary fluid out of which star-mist and nebula were generated, according to the scientific metaphysic of the present day. Is it any wonder, then, that many of the major premises of Nature’s physical syllogisms should still be wrapt in impenetrable mystery to us, as many of the major premises which * Bacon’s oft-quoted contrast between metaphysicians, who, he says, spin ‘‘Jaborious cobwebs of learning,’’ like spiders, and physical philosophers, who ‘work according to the stuff, and are limited thereby,”’ seems hardly fair to the spider. Advancement of Learning, Book J, iv, 5. ANNUAL ADDRESS OF THE PRESIDENT. LIII we have spelled out were wrapt in an impenetrable mystery to the Greeks in the 5th century before Christ? As there is a needs be that much of metaphysic thought must be blended with the psychological processes which lead to every passage from the known to the unknown; so every great discovery of the physical philosopher tends to widen the metaphysical horizon within which he works. The world was never so full of metaphysic as it is to-day, when physical science is transforming the minds of men not so much by the secular boons it is dropping in the lap of modern civilization as by its underlying doctrines; and these doc- trines are often the mere metaphysical reflex or obverse of the physical truths they subtend. The psychological processes of every age are conditioned by its logical method, and its logical method is justified to itself by its metaphysic—by those necessary conceptions and fundamental relations which it takes to be architectonic of the Universe. What, for instance, can be more metaphysical than the latest conception of our highest physical science—the conception of vortex atoms moving in an imaginary frictionless fluid where the origin and the end of the motion are equally inconceivable? Or, take Mr. Darwin’s doctrine of hypothetical gemmules “ inheriting innumerable qualities from ancestral sources, circulating in the blood and propagating themselves, generation after generation, still in the state of gemmules, but failing to develop themselves into cells because other antagonistic gemmules are prepotent and over- master them in the struggle for points of attachment” *—in what respect is this doctrine one whit less metaphysical than St. Augus- tine’s doctrine of original and hereditary sin? Or, when the late Prof. Clifford tells us that “the Universe consists entirely of mind- stuff;” that “ matter is a mental picture,in which mind-stuff is the thing represented,” and that “ reason, intelligence, and volition are properties of a complex which is made up of elements themselves not rational, not intelligent, not conscious”—how does his “ mind- stuff” differ from the “ mind-stuff” of Pythagoras, + except in the * Galton: Hereditary Genius, p. 367; cf. Darwin: Animals and Plants under Domestication, (London,) vol. 2, p. 402. For a criticism on this physiological doctrine, see Encyclopedia Britannica, (‘‘Atoms,’’) vol. 3, p. 42. + For the ‘‘mind-stuff’’ of Pythagoras, see Cicero, De Nat. Deorum, I, xi, 27. For the ‘‘mind-stuff’”’ of Clifford, see ‘‘ Mind,’’ January, 1878, p. 66. LIV PHILOSOPHICAL SOCIETY OF WASHINGTON. greater ingenuity and method of the metaphysic art with which it is conceived ? 7 If within the limits of this discussion I had the time, and if, under the limitations of my knowledge, I had the ability, to carry this enquiry into the realm of molecular physics and dynamics, where such star-eyed mystagogues as a Clausius or a Rankine, a Clerk-Maxwell or a Sir William Thompson have borne the thyrsus of science before us, it would be easy to show that, under their guid- ance, we have escaped the pitiless parallel lines of the Epicurean atoms only to find ourselves inextricably implicated in the knotted- ness and linkedness of the vortex rings of atoms as they execute their infinite evolutions and invyolutions, vibrating now in one period and now in another behind that vail of matter where they can be descried only by the shadowy lines they reveal to the spectroscopic imagination. “It is the mode of motion,” says Clerk-Maxwell, “which constitutes the vortex rings, and which furnishes us with examples of that permanence and continuity of existence which we are accustomed to attribute to matter itself. The primitive fluid, the only true matter, entirely eludes our perceptions when it is not endued with the mode of motion which converts certain portions of it into vortex rings, and thus renders it molecular.” * Of these vortex rings we must say, in the dialect of the schools, cognoscendo ignorantur, sed ignorando cognoscuntur. Withheld from positive conception, yet necessitated to scientific thought and spec- ulation by the exigencies of the knowledge we can conceive posi- tively, they afford a good illustration of the physical metaphysic which has wafted the scientific mind of the present generation into an empyrean as much higher than the empyrean of Plato as the spectroscopic vision of modern science is more far-reaching than the highest flight of metaphysic wit among all the physical atomizers who ever lived or dreamed in Greece. Every chemical atom, says Sir John Herschel, is forever solving differential equations, which, if written out in full, might belt the earth. ‘An atom of pure iron,” says Jevons, “is probably a vastly more complicated system than that of the planets and their satellites.” Between metaphysical physics and physical metaphysics there is a world-wide difference. The invisible ether posited behind the * Encyclopedia Britannica, sub voce ‘‘Atom.”’ ANNUAL ADDRESS OF THE PRESIDENT. LV vail of matter by the East Indian philosophy of the Upanishads, or by the visionary dialectic of Cleanthes, was posited there by meta- physical physics. The invisible fluid posited by modern science behind the vail of matter is posited there by physical metaphysics. The vortices of Democritus as well as the vortices of Descartes are the creations of metaphysical physics. The vortices of Helm- holtz and of Sir William Thompson are the creations of physical metaphysics. The fixed and crystalline sphere of the old Ptole- maic astronomers was an invention of metaphysical physics. The solid ether which transmits to us the light of the stellar Universe, and which, as Sir John Herschell remarks, is the modern “ realiza- tion of the ancient idea of the crystalline orb,” is the invention of physical metaphysics. When Lucretius finds in the iridescent hues of the peacock’s tail, as it shimmers in the sun, a fresh type and instance of Nature’s prodigality in the display of atoms, he does but yield another contingent to the barren store of his meta- physical physics. When Dr. John Tyndall finds in the iridescences of the common soap bubble a proof that stellar space is a plenum filled with a material substance that is capable of transmitting motion with a rapidity that would girdle the equatorial’ earth eight times in a second, he does but yield another contingent to the fertile store of his physical metaphysics. When Dr. George Cheyne, of Scotland, expressed the opinion in the last century, that “all ani- mals, of what kind soever, were originally and actually created at once by the hand of Almighty God, it being impossible (he said) to account for their production by any laws of mechanism ;” and when he further held that “every individual animal has, in minimis, actually included in its loins all those who shall descend from it, and every one of these again has all its offspring lodged in its loins, and so on ad infinitum,” and that “all this infinite number of ani- malcules may be lodged in the bigness of a pin’s head,’’* he preached a biological doctrine which sounds in the terms of metaphysical physics. When Mr. Darwin in his provisional theory of Pangenesis assumes the existence of the gemmules which inherit innumerable qualities from ancestral sources, and which prelude as gemmules that struggle for existence which antedates and therefore condition- ates the terms of the human struggle witnessed in society, commerce, and national life, he expounds a biological doctrine which sounds just as clearly in the terms of physical metaphysics. When old * J. Brown: Locke and Sydenham, p. 270. LVI PHILOSOPHICAL SOCIETY OF WASHINGTON. Heraclitus proclaimed that the Universe with all it contains sprang into being from elemental heat, and was destined to be resolved again into the elemental heat from which it sprang, and thus in a ceaseless round to continue the cycle of being, he taught a doctrine of conservation and correlation of energy which had its root in metaphysical physics. When Dr. John Tyndall declares that “all our philosophy, all our poetry, all our science, all our art—Plato, Shakespeare, Newton, and Raphael—are potentially in the fires of the sun,” and so tucks away the genius of a Darwin in the folds of a nebular blastema, he teaches a doctrine of equivalence which has its root in physical metaphysics. It will thus be seen that under the dominion of Science the world has use for as much metaphysic as ever before, but only for a meta- physic radically different from the old metaphysic in its point of departure as also in the tests of its validity, and, therefore, radi- cally different in the tenure by which it is held. The votaries of the old metaphysical physics proceeded from what was unknown to explicate and explain the known appearances of things, and rested content in explanations which seemed to consist with those appear- ances. The votaries of the modern physical metaphysics proceed from what is known to explicate and explain what is unknown in the deeper relations of things, and rest content in explanations only so long as, and so far as, they seem consistent with experimental proofs or with the broadest homologies of the deductive reason. When the law of simple multiples in chemical combinations was given to the world by Dalton, and was expressed by him in atomic language, he had really made a great departure from the physical methods of Democritus, though it is curious to observe that there is a perfect identity between the metaphysical ideas underlying his logic and the metaphysical ideas of his Greek predecessor. The method of each proceeds on the assumption of the indestructibility of matter, and it is from this platform that the English chemist reaches out his hand to the Greek philosopher in token of a com- mon metaphysic. “No new creation or destruction of matter,” wrote Dalton, in his celebrated paper on “ Chemical Synthesis,” “is within the reach of chemical agency. We might as well attempt to introduce a new planet into the solar system, or to annihilate one already in existence, as to create or destroy a particleof hydro- ANNUAL ADDRESS OF THE PRESIDENT. LVII gen.” * Democritus knew nothing of hydrogen, but he saw as clearly and said as plainly as Dalton that the antecedent premise of all physical philosophy must be found in the metaphysical maxim that “out of nothing nothing comes, and that nothing which is can ever be annihilated.” And this maxim, with which the old Greek philosophy began, is about all of solid and sound that remains to us from the physical philosophizing of the ancients. It is true, as Mr. Balfour Stewart remarks, that the ancients had in some way grasped the idea of the essential unrest and energy of things; that they had the idea ot small particles or atoms as the constituent elements of matter, and divined the existence of an ethereal medium extending through all space; but there is no evidence at all to support the statement that any one or all of these doctrines proceeded from even a ru- dimental conception of “the most profound and deeply seated ot the principles of the material universe.” There is, however, one respect in which it may be justly said that Democritus stands at the head of the long line of natural philoso- phers who since his day have been explicating for us the structure of the physical universe. He was the first who ever attempted a purely mechanical solution of the problem of physical being. It is the singular glory of the atomic philosophers that alone, among the jarring schools of Greece, they saw that a science of the Universe was possible only on the assumption that the phenomena of the physical universe are bound together by necessary law, and this law mechanical in the modes of its operation. They had no science, it is true, in the modern sense of the word, but it is no small dis- tinction which they have won in standing at the head of an intel- lectual succession which embraces in its ranks a Copernicus and a Galileo, a Newton and a Laplace, a Dalton and a Faraday. { * Henry: Memoirs, &c., of Dalton, p. 88. { Diog. Laert., sub voce ‘‘ Democritus,” where it is particularly recorded that he assumed as his point of departure the maxim ‘Out of nothing nothing comes,’’ &c. t‘‘ Was die Atomiker von ihren Vorgangern unterscheidet, ist nur die Strenge und Folgerichtigkeit mit der sie den Gedanken einer rein material- istischen und mechanischen Naturerklérung durchgefithrt haben; diese kann ihnen aber um so weniger zum Nachtheil gedeutet werden, da sie damit nur die Schliisse gezogen haben welche durch die ganze bisherige Entwicklung gefordert, und wozu in den Annahmen ihrer Vorginger die Vordersatze ge- geben waren.’”’ Zeller: Philos. d. Griechen, Erster Theil, 765. LVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. With two short lessons cited to point the moral of this long story, and I have done. The first of these moralities shall” be a warning | against the folly of the old atomists in attempting to philosophize beyond the conditions of their knowledge. They reared imposing fabrics in astronomy, in physics, in psychology, and in anthropology, but they built without laying their foundation in any deep knowl- edge of nature, and laid the successive courses of their system- building in the untempered mortar of an incoherent logic. And the moral needs to be pointed as much for the admonition of modern scientific workers, with their cheap and easy cosmologies, as for the reproach of the old physiologers of Greece. One of our poets has sung: From an old English parsonage Down by the sea, There came in the twilight A message to me. Its quaint Saxon legend, Deeply engraven, Hath, as it seems to me, Teaching from heaven; And all through the hours The quiet words ring, Like a low inspiration, “Doe the nerte thyuge.” The message is as full of inspiration for guidance in physical philosophizing as for guidance in moral conduct. Tantwm series juncturaque pollet. The only other morality which time permits to be pointed at the end of this review is a warning against intellectual impatience— not that intellectual impatience rebuked by the maxim just cited, and which seeks to leap at a single bound the limitations of knowl- edge in any given age—but the intellectual impatience which cayils at the short-comings of the men who dug the first ditches and planted the first hedges around the vineyards of science. They were humble pioneers, but they opened the way into that land of Beulah where the men of science sit to-day beneath their own vines and fig-trees, with none to make them afraid. Even after John Dalton had come to place the key of the new Atomic Philoso- phy in the hands of men, it was a saying of Mitscherlich that it took fourteen years to discover and establish a single fact in ANNUAL ADDRESS OF THE PRESIDENT. LIX chemistry. Let us not wonder, then, that it took more than two thousand years to perfect the doctrine of atoms as a clew to the “mystery of matter.” Democritus invented a mechanical key of wonderful ingenuity, but it would not unlock anything that could not be unlocked without. it. Newton divined that the key must be fitted to the two great wards of chemical attrac- tion and chemical repulsion, but still the key would not turn in the udamantine lock of Nature. Dalton found that the secret of the combination must be sought in wards nicely graduated according to certain fixed, definite, and multiple numbers, and, since his day, door after door in the chemist’s “chamber of imagery” has seemed to swing open at the touch of this talisman. And even, if in the next two thousand years, or in the next twenty years, the theory of John Dalton should be absorbed in some deeper truth, there will still be room in the pantheon of science for the memorial bust of the plain Manchester arithmetician, so long as men recall how far that little candle, which he lighted with inflammable gas obtained in the rudest way from the ponds of Lancashire, has thrown its quickening beams across the whole tract of modern chemistry. ie nye A AY ee iy a vat eae, oy ue Waal | ust Wariate, teem i } 4 i And a Ng d Le iy a2 Aah Ast PACS EAE ATEN A sf) : PhP ht tb, Ay ba th ay Wed Me Dina SSD RN 0 4 ” NS a oe ‘on ed a RP a, : Mh ee it . Rs fea hey er b i ‘AS a 4 is Yi Pid beni { Chan hi “" P PA tay SEC sy ad Pa ; : * Lh Aa CARRS SEL De DNAS ah ANE ee ; f PAU te CeO enn Bene ‘ny tag ae : cacy who BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. GENERAL MEETING. BULLETIN OF THE GENERAL MEETING. 244TH MEETING. JANUARY 5, 1884, The President in the Chair. Twenty-eight members and guests present. The Chair announced the death, since the last meeting, of General A. A. HumpHreys, one of the founders of the Society. Mr. J. R. EAstMAan made a communication on THE ROCHESTER (MINNESOTA) TORNADO, describing the ground as it appeared a few days after the storm, and showing that the phenomena did not indicate cyclonic motion. All disturbed objects were thrown in essentially the same direction, and were pressed down rather than lifted. Mr. Exxiorr related that twenty-five years previous he had crossed a storm-track consisting of a double line of fallen timber, with an interval in which the timber was standing. Mr. Eastman thought this phenomenon should be referred to two separate cyclones, possibly moving as companions. Mr. Dauu described storm tracks in the Escanaba region in which the trunks of prostrate trees pointed uniformly in one direction, the path of destruction being definitely limited at the margins. Mr. E. Farquaar suggested that a highly inclined storm axis might account for the uniformity in the direction of the wind in the zone of destruction. 3 A PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. W. H. Datu read a paper on RECENT ADVANCES IN OUR KNOWLEDGE OF THE LIMPETS, summarizing the researches of Spengel on the sensory organs or osphradia; Cunningham on the renal organ and renopericardial pore in Patella and Patina; Fraissé on the eye in Patina, Fissurella and Haliotis, and the speaker on the presence of an intromittent. male organ in Cocculina. He stated that among the Acmeide and Patellide the type of eye differs, and while in Patina it is of a very rudimentary character, in other genera it might be well developed, as, for instance, in Ancistromesus, which has as well developed eyes as Fissurella. He also alluded to the gradual progress in classifi- cation afforded by anatomical investigation during the past few years, and observed that nearly all the known forms except Propili- dium and Scutellina were amenable to classification; our ignorance of the branchize in the former, and the dentition in the latter, operating to prevent a final classification in these two cases, until more is known. Those authors who study the embryology and histology usually from a single species, generally ignore the wide differences of adult anatomy between the genera of Limpets, and sow their generalizations on a basis of classification which is little in advance of that of Lamarck and his immediate successors. Professor C. H. Hircucock being present was invited by the Chair to address the Society, and responded briefly. The President of the Society then pronounced a brief eulogy on General Humphreys, characterizing him as a man who had left behind him an honorable name as well for his distinguished achievements in science and in war as for the virtues and graces which adorned his private life. Mingling among his fellow-men with the utmost unobtrusiveness, and as gentle in spirit as he was brave in conduct, he brought the highest intelligence as well as the highest conscientiousness to the discharge of all the duties—scien- tific, military, and administrative—with which he filled his long and useful life: a life fitly closed by the serenity and peace of his beautiful death, Ki GENERAL MEETING. 5 245TH MEETING. JANUARY 19, 1884. The President in the Chair. Forty-five members and guests present. The Chair read a letter from the Biological Society of Washing- ton inviting the members of the Philosophical Society to attend its meeting of January 25th, for the purpose of listening to the annual address of its President, Dr. C. A. White. Announcement was made of the election to membership of Messrs. GEORGE Epwarp Curtis and Patrick Henry Ray. Mr. I. C. RusseLt made a communication on THE EXISTING GLACIERS OF THE HIGH SIERRA OF CALIFORNIA. [Abstract. ] During the summer of 1883 I had an opportunity of tracing to their sources some of the ancient glaciers of the High Sierra in the region between Mono Lake and the Yosemite Valley. From the glacial records seen during a number of excursions into the mountains it was evident that the High Sierra had formerly been so deeply covered with ice that only the culminating peaks and ridges escaped the general glaciation. From the vast névé of the mountain tops flowed long winding rivers of ice, both to the eastward and westward through the cafions and valleys. In nearly all cases the glaciers occupied drainage lines of pre-glacial date, which they modified and enlarged, but, with the exception of the cirques about the higher peaks and crests, they failed to originate any of the more prominent topographical features of the range. The glaciers of the Sierra Nevada were not connected with a north- ern ice-sheet, but were of local origin and of the same type as the Swiss glaciers of the present day, but of far greater magnitude. If the cafions and valleys of the Sierra are traced upward, it is almost invariably found that they head in cirques or amphitheaters, in some of which small glaciers still linger—perhaps remnants of the mighty ice-rivers that formerly flowed from the same fountains. The first glacier visited by the writer was on the northern side of Mt. Dana, at an elevation of about 11,500 feet above the sea, and at the head of a deep cafion which drains into Leevining creek, 19 6 PHILOSOPHICAL SOCIETY OF WASHINGTON. one of the tributaries of Mono Lake. The Mt. Dana glacier is approx- imately 2,500 feet long and of somewhat greater breadth. Although small, and in fact but a “ pocket edition” of what may be seen on a far grander scale in many mountains, yet it is a veritable glacier, with nearly all the features that characterize such ice-bodies in other countries. The distinction between the snow-ice of the névé and the more solid blue or greenish-blue ice of the glacier proper is clearly marked—as was observed to be the case also in a number of neighboring glaciers. An irregular open fissure crosses the head of the névé, corresponding to the “ bergschrund ” of the Swiss glaciers, while a number of parallel fractures on the border of the glacier at the foot of the snow-field form marginal crevasses with walls of solid blue ice. Near the terminus of the glacier alternating sheets of porous, white ice, and of more compact bluish ice were observed, which produce a distinct laminated or ribboned structure. Dirt-bands were plainly visible, sweeping in undulating lines across the surface of the glacier; and similar bands are a conspicuous feature in nearly all the ice-bodies seen in the High Sierra. About the foot of the Mt. Dana glacier a true terminal moraine is now in process of formation. The fall of stones and dirt from the ice onto the moraine was noticed many times during our visits. Some of the rounded stones from beneath the ice are battered and scratched and have evidently received these markings within the past few years. On the northern side of Mt. Lyell another glacier was visited, which is the source of the Tuolumne river. The Mt. Lyell glacier is somewhat larger than the one on Mt. Dana, and, like it, exhibits characteristic glacial phenomena. A protrusion of compact, banded ice from beneath a snow-field at the head of an amphitheatre was here again observed, as well as the presence of moraines, crevasses, dirt-bands, ete. On the lower portion of this glacier were observed “ice-pyramids”’ of the form represented in the figure on the follow- ing page. At the northern base of a pyramid there invariably occurs a stone or a mass of dirt, that is depressed below the general surface of the glacier, as is indicated in the sketch. The pyramid invariably points toward the noon-day sun. IJts mass is composed of porous and banded ice, like that forming the general surface of the glacier, but its northern face is sheeted with compact, bluish ice. The GENERAL MEETING. ‘i northern face is also concave, as represented in the sketch, and usually conforms to some extent with the shape of the stone at its base. Fie. 1. An Ice-Pyramid. On another glacier, discovered at the head of Parker creek, one of the tributaries of Mono Lake, all the glacial phenomena: men- tioned above are well displayed, and, in addition, “ glacier-tables ” were observed in considerable numbers. The following figure repre- sents several of the glacier-tables of the Parker creek glacier, grouped for convenience of illustration : a = = if) mars { 4 GE Tos Fig. 2. Glacier-Tables. 8 PHILOSOPHICAL SOCIETY OF WASHINGTON. The largest perched-block now being carried along by this glacier measures 34 by 28 by 10 feet, and is supported on & column of ice five or six feet thick, eight feet high on its northern side, and six feet high on its southern. Many masses of rock larger than the one measured were seen in the terminal moraine that circles about the foot of the glacier. ; The motion of these glaciers was not observed, but that it exists is manifest from the nature of the crevasses and the curvature of the dirt-bands. The rate of flow of a glacier on Mt. McClure was measured several years since by Mr. Muir, who found it to be 47 inches in 46 days (from August 21st tc October 6th, 1872).* Six glaciers are known to the writer within the southern rim of the hydrographic basin of Mono Lake, and about twice this num- ber were seen about Mt. Conness, Mt. McClure, Mt. Lyell, Mt. Ritter, and the Minarets. Many of the glaciers mentioned above have been previously re- ported in popular articles by Mr. John Muir, but the fact that they are true glaciers haying been denied by eminent geologists, it is de- sirable to have a more accurate description of them. [The communication was illustrated by photographic lantern views. Its subject-matter will be more fully presented in the Fifth Annual Report of the United States Geological Survey. ] Mr. Girpert THompson described certain glaciers on Mount Shasta believed to be new to science. Their discovery increases the number of known glaciers on the flanks of Shasta to seven. Mr. Houmes described modern glaciers of the Rocky Mountains observed by himself. Those of the Wind River Mountains are from one-fourth mile to one mile in length. He illustrated by a sketch the position of three small glaciers in the gorges of Mount Moran, in the Teton Range, at an altitude of 10,000 feet. Mr. PowEtu remarked that the chief interest of these small modern glaciers lies in the fact that they illustrate the process by which the drift has been distributed, and aid in completing the theory of the ancient glaciation of the country. Mr. Marx B. Kerr mentioned the occurrence of a probable glacier in the Salmon Mountains, a division of the Coast Range. e * American Journal of Science, Vol. V, p. 69; 1878. GENERAL MEETING. 9 Mr. Harkness set forth the apparent difficulty of discrimina- ting between a névé and a glacier proper, and requested that some geologist would define the term “glacier.” Mr. Emmons said that a true glacier is an ice river, conform- ing in shape to the more or less restricted channel in which it flows, and this characteristic might form a base of distinction be- tween the true glacier and the névé-field, the latter being com- parable to the lake which forms the source of a mountain stream. Thus the névé would become a glacier only when from a broad and shallow ice-field it had become compressed into a narrower and deeper mass, between confining walls. Other remarks were made by Messrs. E. FARQUHAR, GILBERT, Datu, and ELiiort. Professor W. C. KERR made a communication on THE MICA MINES OF NORTH CAROLINA. [Abstract. ] The profitable mines are restricted to a plateau limited eastward by the Blue Ridge and westward by the Smoky Range. These were anciently worked on a very extensive scale. Few other modern mining operations have been so profitably conducted as those at the points occupied by the early miners. The ancient work was per- formed with blunt-pointed tools—doubtless of stone—and was con- fined to the partially decomposed portions of the granite veins, but large pits were nevertheless excavated. One of these measures 150 by 75 feet, and, despite a partial filling with débris, retains a depth of 35 feet. Facts connected with the arboreal vegetation show that some, and perhaps all of these openings were aban- doned as much as five hundred years ago. The modern industry began in 1868, and, although it has assumed considerable import- ance, is not yet conducted in a systematic way. The character of the mica and its associated minerals were dis- cussed and illustrated by specimens. 10 PHILOSOPHICAL SOCIETY OF WASHINGTON. 246TH MEETING. FEBRUARY 2, 1884, The President in the Chair. Forty-eight members and guests present. The Chair announced the election to membership of Mr, Taomas ROBINSON. Mr. C. V. Ritry made a communication on RECENT ADVANCES IN ECONOMIC ENTOMOLOGY. The paper set forth the part which insects play in the economy of nature, and particularly their influence on American agriculture. The earlier writers on applied entomology in the United States, as Peck, Harris, Fitch, Walsh, LeBaron, Glover, did some excellent work in their studies of the habits and life-histories of injurious species, but the most important results followed when such studies were combined with field work and experiment by competent persons and upon scientific principles. A number of the remedies proposed in the agricultural press are foolish and based on misleading em- piricism. Economic entomology as a science is of comparatively recent date. It implies full knowledge of the particular injurious species to be dealt with and of its enemies, of its relations to other animals and to wild and cultivated plants. In short, the whole environment of the species must be considered, especially from the standpoint of the farmer’s wants. The habits of birds, more par- ticularly, and the bearings of meteorology and of the develop- ment of minute parasitic organisms must be considered. Experi- ments with insecticides and appliances will then be intelligent and successful in proportion as the facts of chemistry, dynamics, and mechanics are utilized. The complicated nature of the problem was illustrated by the life-history of Phylloxera vastatriz Planchon, and the difficulties often encountered in acquiring the facts were illustrated by the late work on Aletia xylina (Say). The chief insecticides considered for general use and applicable above ground were tobacco, white hellebore, soap, arsenical com- pounds, petroleum, and pyrethrum; those for use under ground, naphthaline, sulpho-carbonate of potassium, and bisulphide of car- GENERAL MEETING. 11 bon. The most advantageous and improved methods of utilizing each were indicated. Recent experiment showed that kerosene emulsions, such as had been recommended lately in the author’s official reports, are superior to bisulphide of carbon when used under ground against the Grape Phylloxera, and the discovery is deemed of great importance, especially to the French people and those on our Pacific slope. Contrary to general belief, pyrethrum powder was shown to have a peculiar and toxic effect on higher animals as well as on the lower forms of life. Its deadly influence on lower organisms led the author to strongly recommend its use as a disinfectant, and to express the belief that it will yet come to be used in medicine. Dr. H. A. Hagen’s recommendation of the use of yeast ferment was touched upon. It has proved of little or no practical avail, and some of the publications on the subject were characterized as unscientific. The use of malodorous substances as repellants, which was much relied on in the early days of econ- omic entomology and strongly recommended by the two Downings, has latcly been agitated as a new principle for the prevention of insect attack by Prof. J. A. Lintner. The principle can be applied in exceptional cases to advantage, but experiment gives little hope of its utility against most of our worst field insects. Prof. S. A. Forbes is engaged in interesting researches, having for object the utilization of micro-organisms, but with more promise for pure than applied science. Of recent progress in mechanical appliances, the paper dealt with those lately perfected under the author’s direction by Dr. W. S. Barnard, one of his assistants. This part of the subject was illustrated by models and by plates from the forthcoming fourth report of the United States Entomological Commission. The paper concluded with the following plea for applied science: “Matters of fact do not tend to provoke thought and discussion; and I must confess to some misgivings in bringing these practical considerations before a body which reflects some of the highest and purest science and philosophy of the nation. From the days of Archimedes down to the present day there has existed a disposition to decry applied science and to sneer at the practical man. Yet I often think that science, no matter in what fine-sounding name we clothe her, or how high above the average understanding we stilt her, is, after all, but common sense employed in discovering the 12 PHILOSOPHICAL SOCIETY OF WASHINGTON. hidden secrets of the universe and in turning them to man’s wants, whether sensual or intellectual. Between the unbalanced vapor- ings of the pseudo-scientific theorizer and the uninformed empiric who stumbles upon a discovery, there is the firm middle ground of logical induction and deduction, and true science can neither be exalted by its inapplicability, nor degraded by its subserviency to man’s material welfare. The best results follow when the pure and the applied go hand-in-hand—when theory and practice are wedded. Erstwhile the naturalist was honored in proportion as he dealt with the dry bones of his science. Pedantry and taxonomy over- shadowed biologic research. To-day, largely through Charles Dar- win’s influence, we recognize the necessity of drawing our inspira- tion more directly from the vital manifestations of nature in our - attempt to solve some of the many far-reaching problems which modern science presents. The fields of biology, morphology, physi- ology and psychology are more inviting than formerly. Nor is the lustre that glorifies the names of Stevenson, Watts, Faraday, Franklin, Morse, Henry, Siemens, and a host of yet living investi- gators dimmed because they made science useful. Goethe makes Wagner say: ‘‘Ach wenn man so in sein Museum gebannt ist Und sieht die Welt kaum einen Feiertag Kaum durch ein Fernglas, nur yon Weiten Wie soll man sie durch Ueberredung leiten?’ “Tf to-day, right here in Washington, there is great activity in the field of original research; if the nation is encouraging it in a manner we may well be proud of, the fact is due in no small degree to the efforts of those, many of them members of this Society, who have made practical ends a means, rather than to those who would make science more exclusive, and who are indifferent to practical ends or popular sympathy. Such, at least, is my apology for the nature of this paper.” In response to an inquiry by Mr. White, Mr. Rrury said that the ox-eye daisy. had been subjected to a thorough test under his supervision and the result had shown that it has none of the insect- icide qualities of pyrethrum. os GENERAL MEETING. 13 Mr. S. M. Burnett made a communication entitled WHY THE EYES OF ANIMALS SHINE IN THE DARK.* [Abstract. ] Erroneous opinions have been held and expressed, not only by the non-scientific, but also by some persons holding high positions in the scientific world, in regard to the phenomena of luminosity of the eyes of animals, and particularly of cats, when they are in ob- scurity. It is not due, as has been commonly supposed, to phosphor- escence, but to light reflected from the bottom of the eye, which light is diffused on account of the hypermetropic condition that is the rule in the lower animals. In response to a question by Mr. White, Mr. Burnerr said that human eyes affected by hypermetropia do not yield similar results, partly because the human pupil is too small and partly because the bottom of the human eye is not so strongly reflecting a surface as that of most animals. Mr. Harkness remarked that in determining the degree of di- vergence of rays emitted by an eye, from an image situated upon its retina, it is necessary to consider the magnitude of that image as well as its distance from the focal plane of the lens. The diver- gence of the rays coming from any one point of the image is deter- mined by the interval which separates the retina from the focal plane of the lens, while the divergence of the rays coming from any two points of the image depends principally upon the size of the image itself. The total divergence is the sum of the divergences produced by these two causes, and the neglect of that due to the size of the image will probably account for the discrepancy between the observed angle of divergence and that computed by Dr. Burnett. It also seems desirable to bear in mind the distinction between fluorescent and phosphoresent light ; the former disappears as soon as the incident waves are cut off; the latter does not. * This paper is published in full in the Pop. Sci. Monthly for April, 1884; Vol. XXIV, pp. 813-818. 14 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. A. B. Jonson made a communication on SOME ECCENTRICITIES OF OCEAN CURRENTS, [Abstract. ] The records of the Light House Board show that no less than eleven buoys of various patterns have gone adrift from the waters of the United States and been found at distant points where ocean currents have carried them. Many of these were not so fully iden- tified that their precise original station could be indicated. In the case of a few, it has been determined that they were swept from the harbor and bay of New York by the outgoing ice in the winter of 1880-81 when nineteen buoys were carried to sea. 1. In the spring of 1871, a buoy was picked up on the west coast of Ireland. 2. In March, 1871, the Norwegian vessel Vance picked up a buoy in lat. 42° 22’, long. 26° 38’. 3. In February, 1881, a buoy went ashore on one of the cays near Turk’s island. This was recognized as a New York buoy. 4. May 17, 1881, the steamer William Dickinson passed a whist- ling buoy in lat. 29° 46’, long. 77° 38. 5. In March, 1881, a buoy of the largest size, likewise referred to New York, was found near Bermuda. 6. In February, 1882, a Sandy Hook buoy was found near Ber- muda. 7. In February or March, 1882, a buoy was washed ashore at Pendeen Cove, Penzance Bay, England. 8. In the spring of 1882, the Swedish bark Abraham Lincoln picked up a buoy in lat. 32° 30’, long. 28° 40’. 9. October 22, 1883, a buoy was picked up on the east side of Teneriffe in lat. 28° 21’, long. 16° 15’. 10. October, 1883, a second buoy was picked up fifteen miles from the east coast of Teneriffe. 11. August 20, 1883, the British bark Jane Richardson picked up a buoy in lat. 24° 11’, long. 32° 48’, GENERAL MEETING. 15 All were identified as the property of the United States by letters cast in the plates. The charted currents of the ocean readily explain the courses and account for the positions of many of these buoys, but others appear anomalous. Mr. JENKINS cited an instance of a bell-buoy, carried away from the coast of the United States in 1850, which was seen and heard while adrift and finally stranded on the southwest coast of Ireland. Mr. WELLING suggested that the phenomena might not be refer- able to ocean currents exclusively, but in part to wind currents. Mr. Jonnson judged from the forms of the buoys that their move- ments would be controlled more by currents than by winds. Mr. H. Farquuar and Mr. JENKINS were of opinion that the buoy picked up off Florida might have been carried there by the southward coast-current. Mr. Dawu concurred, but thought it also possible that it had made the entire circuit of the Sargasso sea. Mr. Daut, referring to Mr. WELLING’s suggestion, said that wind and current worked together, and their effects could not be discriminated. The wind does not blow prevailingly in any direc- tion without coercing currents to correspondence. 247TH MEETING. FEBRUARY 16, 1884. The President in the Chair. Fifty-four members and guests present. The Auditing Committee reported through its Chairman, Mr. C. A. Wuirs, that it had examined the accounts of the Treasurer for 1883, finding the same properly vouched in respect to expenditures and receipts. On motion of Mr. Durron, the report was accepted. The Chair announced the election to membership of Mr. Henry Wayne Buair and Mr. Hersert GoUVERNEUR OGDEN. Mr. F. W. CLARKE made a communication on THE PERIODIC LAW OF CHEMICAL ELEMENTS. After giving an account of the law as worked out by Newlands, Mendelejeff, and Lothar Meyer, he exhibited an enlarged copy of 16 PHILOSOPHICAL SOCIETY OF WASHINGTON. Meyer’s atomic volume curve, drawn with the latest values for both atomic weight and specific gravity. On the same,sheet was also drawn a similar curve, illustrating the connection between atomic weight and melting point, and it was shown that in the latter the highest portions correspond to the lowest depressions in the atomic volume curve. The opinion was expressed, in view of the regu- larities exhibited by these curves, that the elements had originated by some method of evolution, and that a future transmutation of one element into another was not improbable. In reply to a question by Mr. Farquhar, Mr. CLARKE said that search was being made for similar evidence of system in the spectra of the elements, but that the subject was rendered difficult by reason of the fact that not all the lines of the spectra fall within the range of visibility. ' Mr. ANTISELL remarked that while the determination of the atomic weights of the elements was one of the most important labors which the modern chemist could be occupied with until a final constant numerical result should be arrived at, and until the other properties of matter which appear to have some definite relation with the atomic weight were rigidly investigated, there was necessity for continued effort to search into those hidden relations; but if by such investigation it was believed that we could arrive at any certainty about atoms, their form and structure, or about matter itself, we should be much disappointed. Situated as we are on a cold planet, we are precluded from ever arriving, by the study of matter from a standpoint merely terrestrial, at any ideas of the ultimate nature of atom or molecule, or whether there be really any such thing as “elements” or one form of matter wholly dis- tinct from another. ‘To arrive at a knowledge of matter, pure and simple, we must have ready means for dissociating all compound matter, and we have at our command at present no such methods or apparatus on this globe. Subjection to intense heat is required, and our most glowing furnaces and the are light itself is insufficient for the purpose. It calls for the exhibition of such heat as is pro- duced in the sun and its atmosphere to reduce our elements, as we term them, to the more simple condition of matter as it exists under solar temperature, and the present spectroscope and its.future im- provements by which such dissociation is to be studied. The GENERAL MEETING. fu § investigations of Huggins and Lockyer and other spectroscop- ists have revealed to us the presence of several of our so-called elements in the solar atmosphere; but constant observation has raised in the minds of these observers grave doubts whether the spectral lines of the elements, as obtained by observation of them in our atmosphere, are universally of such or whether only con- ditionally so, that is true only in our cold atmosphere. Doubts have arisen as to the spectral lines of elements being permanent characters of their essential nature, seeing that the spectral lines of an element, which at one time resemble those of copper, are found to be interchangeable and attached to a different element, as calcium, and that there are elements which possess the character of giving multiple spectra, as carbon, for example, which, under these solar temperatures, yields no less than three distinct and charac- teristic spectra. In view of these apparently contradictory and confusing results, obtained by the examination of matter found in the solar atmos- phere, which are so different from those obtained from matter in our own atmosphere, it behooves us to be very cautious in asserting the existence of any distinct elements so called, or whether there be only one matter under various cosmical conditions. Other remarks were made by Messrs. DooLiTrLE and WHITE. Mr. H. A. Hazen made a communication on THE SUN-—GLOWS, opposing the theory that they are due to dust, either cosmic or vol- canic, and advocating a theory involving electrical action in con- nection with frost particles.* A general discussion followed, in which Messrs. ELurorr, PAvut, Rosinson, Hauy, Durron, GILBert, and E. Farquyar, partici- pated. Mr. Exxiorr advocated the electrical origin of the glows, basing his argument on the simultaneousness of the phenomena through- out the planet, on the transparency of the glow as shown by obser- vations on Lyre, and on the extraordinary abundance of sun spots for the past few weeks. * This paper is published in full in the American Journal of Science for March, 1884; Vol. XX VII, pp. 201-212. c 18 PHILOSOPHICAL SOCIETY OF WASHINGTON. 248TH Mrerinc. Marcu 1, 1884. The President in the Chair. Forty-two members present. The Chair announced that Messrs. CHARLES Oris BouTELLE, GitBert THompson, WILLARD DRAKE JOHNSON, and EUGENE RicKsECKER had been elected to membership. It was announced from the General Committee that standard time would hereafter be recognized in the opening and closing of the meetings. Mr. R. D. Mussty read a paper entitled THE APPLICATION OF PHYSICAL METHODS TO INTELLECTUAE SCIENCE. The aim of the paper was to show in how far those methods which had been successfully employed in the investigation of the phenomena of nature, and which were denominated the Physical Sciences, were applicable to those sciences, the subject-matter of which were mental operations and their results, and which, for dis- tinction, might be named the Intellectual Sciences. Some illustra- tions were given of the application of these methods to the study of the law; and the paper concluded with the remark that its writer desired it to be regarded as a suggestion rather than a solu- tion of the problem stated: “How far and in what way physical methods and physical sciences help thinkers to say Therefore.” Remarks were made by Mr. Roprnson. Mr. I. C. Russe_i made a communication on DEPOSITS OF VOLCANIC DUST IN THE GREAT BASIN. [ Abstract. ] In contrast with the aridity of the Great Basin at the present time, geologists have shown that during the Quaternary it was crowded with lakes. In studying the sedimentary deposits of one of these fossil lakes, named Lahontan by Mr. King, I found strata GENERAL MEETING. 19 of white, unconsolidated, dust-like material, which is undistin- guishable in general appearance from pure diatomaceous earth. Beds of this material, varying in thickness from a fraction of an inch to four or five feet, were observed at a number of localities in the sides of the cafions that have been carved in lacustrine strata of Lahontan age by the Humboldt, Truckee, Carson, and Walker rivers. Deposits identical with those of the Lahontan sections were observed at a number of localities among the moun- tains of Nevada and California at an elevation of several hundred feet above the former level of Lake Lahontan and at a distance of forty or fifty miles from its borders, thus showing that the deposits were both sub-aerial and sub-aqueous in their mode of accumu- lation. Further exploration revealed the fact.that similar beds occur abundantly in Mono Lake Valley, where they may be seen to pass into well-characterized fragmental deposits of pumice and obsidian, thus suggesting that the finer material was also of volcanic origin. Experiment confirmed this hypothesis. Under the micro- scope the dust from a number of widely separated localities was found to consist almost wholly of angular flakes of transparent glass, with scarcely a trace of crystallized matter. When a sam- ple of pumice from near Mono Lake was reduced to a fine powder, it was found to present the same physical and optical properties as the dust in question, with which it also agreed closely in chem- ical composition, as shown by analyses made by Dr. Chatard, of the Geological Survey. The Mono Craters, from which this dust is supposed to have been erupted, form a group of cones about fifteen miles in length, situ- ated in the southeastern part of the Mono Lake Valley, California. These extinct volcanoes are composed almost entirely of pumice and obsidian, in the condition both of coulées and lapilli, the latter constituting cones of great symmetry and beauty, the grandest of which have an elevation of nearly three thousand feet above Mono Lake. Some of these craters were in eruption during Quaternary times, while others were active after the ancient lakes and glaciers of the region had passed away. Many times during their history vast quantities of lapilli and dust were thrown out. As the volcanic dust interstratified with the sediments of Lake Lahontan is undistinguishable from that deposited in the Mono Basin, there is little room for doubting that they had a common origin. The 20 PHILOSOPHICAL SOCIETY OF WASHINGTON. greatest distance from the Mono Craters at which the dust was observed, was in the Humboldt Cajion, about two hundred miles northward of the point of eruption. At three localities in the Lahontan Basin the bones of extinct mammals were found closely associated with the deposits described above, thus furnishing the suggestion that the showers of fine vol- canic dust were, at least to some extent, fatal to animal life. Mr. ANTISELL said it was useless to look for the source of vol- canic dust in existing volcanoes on the land. Pumice in the character of fine particles, as exhibited, is exclusively the product of submarine eruption. Other remarks were made by Mr. Harx- NESS. Mr. Lester F. Warp read a paper entitled SOME PHYSICAL AND ECONOMIC FEATURES OF THE UPPER MIS- SOURI SYSTEM, in which he described the process by which the valleys of the Lower Yellowstone and Upper Missouri are formed, and pointed out the importance and the feasibility of utilizing the water of these rivers for purposes of irrigation.* Mr. GILBERT said that Mr. Ward’s description of the process by which the Missouri constructs its flood plain was verified by a nearly identical group of phenomena observed by himself on the lower course of the Colorado. Mr. Exxiorr concurred with the speaker’s view that the system of irrigation should be inaugurated by national action rather than local. Mr. Ritry was of opinion that the proposed plan of irrigation was entirely feasible, and said that the final solution of the grasshopper problem lay in the culti- vation of the northern plains. Mr. BurcHarp said that while the political advantage of a con- tinuous belt of settlement uniting the Atlantic and Pacific States was undeniable, he questioned the advisability of increasing at present our agricultural production. * This paper was subsequently separated into its two natural divisions, and the part relating to the ‘‘ physical features ’’ was published with illus- trations in the ‘‘ Popular Science Monthly ’’ for September, 1884 (Vol. XXV, pp. 594-605), while that relating to the ‘‘economic features’”’ appeared in ‘‘Science”’ for August 29, 1884 (Vol. IV, pp. 166-168). GENERAL MEETING. 21 249TH MEETING. Marcu 15, 1884, The President in the Chair. Fifty members present. The Chair announced the election to membership of Messrs. Mark BrickKELL Kerr, SAMUEL Hays KAUFMANN, JOSEPH Sizas DILLER, CHARLES Henry WuHits, and WILLIAM Lavw- RENCE. P Mr. G. K. Gitpert made a communication on THE DIVERSION OF WATER COURSES BY THE ROTATION OF THE EARTH. [Abstract. ] It being admitted that the rivers of the northern hemisphere are, by the rotation of the earth, pressed against their right banks, and those of the southern hemisphere: against their left banks, it re- mains to determine whether this pressure is quantitatively sufficient to appreciably modify the courses of rivers. Opinion is divided, and the results of observation have been largely negative. Those who regard the cause as insufficient to produce observable results have approached the subject from two points of view, which are illustrated by the discussions of Messrs. Bertrand and Buff. The former computes that a river flowing in N. lat. 45° with a velocity of three metres per second exerts a pressure on its right bank of s3ss0 Of its weight, and regards this pressure as too small for con- sideration. The latter points out that the deflecting force, by com- bining with gravitation, gives the stream’s surface a slight inclina- tion toward the left bank, thereby increasing the depth of water near the right bank, and consequently increasing the velocity of the current at the right. This increment of velocity has a certain erosive effect, but it is regarded as less than that assignable to wind waves on the same water surface, so that the prevailing winds have a more important influence than the rotation of the earth. The object of the paper is to consider the theoretical effect from anew point of view. The form of cross-section of a stream flow- ing in a straight channel depends on the loading and unloading of detritus, anti is essentially stable, its character being naturally 22 PHILOSOPHICAL SOCIETY OF WASHINGTON. restored if accidentally or artificially modified. The distribution of velocities within this cross-section is symmetrie, the swiftest threads of the current being in the center and the slowest adjacent to the banks. If now curvature be introduced in the course of the channel, centrifugal force is developed. This centrifugal force is measured by the square of the velocity, and is therefore much greater for the swift central threads of the current than for the slow lateral threads. The central threads, tending the more strongly toward the outer bank, displace the slower threads at that bank, and the symmetry of the distribution of velocities is thus destroyed. As pointed out by Thomson and others, this redistribution of velo- cities determines the erosion of the outer bank and the simultaneous deposition of detritus along the inner bank. It has been shown by Ferrel that the deflecting power of the rotation of the earth upon a body moving on the surface is equiva- lent to the centrifugal force which would be developed if the body followed a circular course with radius of curvature (p) equal to v 2n cos. # | angular velocity of the earth’s rotation, and % the polar distance of the locality. The effect of rotation on a stream being equivalent to a centri- fugal force is identical in kind with the effect of curvature of channel,* and this identity renders a quasi-quantitative comparison possible. Humphreys and Abbott found during flood a mean velocity of the Mississippi river at Columbus of 8.4 feet per second. The value of p corresponding to this velocity and the polar dis- tance of the locality is about 20 miles. The actual bends of the channel in the same region, which depend for their features on the velocity and volume of the river at flood stage, have a radius of In this expression v is the velocity of the body, n the * The author has since seen reason to modify this statement. The two effects are not strictly identical in kind, because the effect of rotation varies with the first power of the velocity, while the effect of curvature of channel varies with the second power. For this reason the selective power of curva- ture is, for the same deflective force, double the selective power of rotation. The introduction of this consideration would modify the numerical results derived from the Mississippi river, but would not impair the qualitative conclusion. A modified treatment of the subject will be found"in the Ameri- ean Journal of Science for June, 1884; Vol. XXVII, pp. 427-482. GENERAL MEETING. a8 curvature of about 13 miles. Centrifugal force being a simple in- verse function of radius of curvature, it follows that the deflective force by which the river is impelled toward its right bank by virtue of rotation is proportioned to the force by which it is impelled toward its outer bank on acute bends in the ratio of 13 to 20. That is to say, in this particular instance -the rotational deflective force is 73 per cent. of the deflective force from curvature of channel. The process of lateral corrasion isso complex that it is impossible to convert this result into terms of erosion and consequent deflec- tion of stream channel, but a consideration of the manner in which the two deflective forces are combined sufficiently indicates that that due to rotation cannot be ignored. Wherever the stream bends toward the left the centrifugal force developed by the curvature is augmented by the rotational force; wherever the stream turns to- ward the right the centrifugal force is diminished by the amount of the rotational force; so that the tendency of the swiftest threads of current to approach the outer bank must be notably greater in one set of bends than in the other. } If this analysis of the subject is legitimate, the rotation of the earth ought surcly to modify the courses of rivers to such extent that the modifications are observable phenomena. Exception should however be made of two important cases: first, rivers which are rapidly deepening their channels are by that fact held rigidly to their original courses, and are not deflected either by rotation or by any other cause; second, those parts of rivers whose function is deposition instead of erosion, should theoretically, under the influence of rotation, built their alluvial plains higher on the right hand side than on the left, and having established an inclination of the alluvial plain toward the left, should thereafter meander over the plain with ‘equal facility in all directions. It is only in the. middle courses of streams, where the work performed by the water is chiefly that of transportation, that the discovery of the effects of rotation should be expected. Mr. Warp remarked that in the regions especially discussed the river courses are, in general, southerly, while the prevailing winds are westerly, so that the influence of the winds is opposed to what- ever influence may be exerted by rotation. Mr. ABBE said that the tendency of driftwood toward certain river banks, cited by 24 PHILOSOPHICAL SOCIETY OF WASHINGTON. von Baer, had been plausibly explained as due to prevailing winds, but such action is purely or chiefly superficial, andsa less important factor in erosion than the behavior of thé main current, which is comparatively little influenced by winds. Nevertheless, he was surprised that the rotational influence admitted of so large a quan- titative expression. Mr. Dawu said that the northward-flowing rivers entering the Arctic ocean afforded at their mouths no evidence of the effect of rotation. The summer winds of Arctic regions are from the north- east and east, and these produce on the north coast of America a shore-current, which drifts the beach sand and shingle westward, and deflects the river-mouths in the same direction. All the rivers from the Mackenzie to Point Barrow illustrate this tendency. On the coast of Siberia the fresh water discharged by the large rivers has been observed to turn eastward, although the winds would tend to throw it the opposite way. The Arctic ocean is there deeper; and it is believed that its principal currents are controlled by the northeasterly set of the general currents of the North Atlantic. Mr. Rogprnson spoke of the indirect influence of wind on river channels, through drifting sand. "Mr. Hazen pointed out that the influence of wind might be eliminated from the problem by study- ing the streams running east or west. Mr. BourreLLe suggested that the course of the Mississippi did not indicate any result of rotational influence. Mr. E. FarquHar inquired whether the behavior of the Gulf Stream and other ocean currents was in accord- ance with the theory of rotational influence; and Mr. Dau re- sponded that in the discussion of ocean currents this cause had lately dropped out of sight, the determination of courses being ascribed to the winds. Mr. Mussey inquired whether the acuteness of continental masses toward the south admitted of an explanation based on the effect of terrestrial rotation; and Mr. Durron responded by saying that the mass of speculation in regard to the recurrence of certain forms of continental outline had never really accomplished more than the statement of the fact. The fact itself is an accident, dependent on the volume of the ocean and the general laws govern- ing the formation of mountain chains. If the ocean were five hundred feet deeper, or five hundred feet shallower, the forms of GENERAL MEETiNG. 25 continents would be so far different that all the existing resem- blances would disappear... The pointed extremities of some conti- nents are merely expressions of the fact that mountain chains are more or less linear, and do not hold the same height throughout their whole extent. Mr. G. E. Curtis read a paper on THE RELATIONS BETWEEN NORTHERS AND MAGNETIC DISTURB- ANCES AT HAVANA, upon which remarks were made by Messrs. ABBE and COFFIN. [It will be published by the Army Signal Office as Signal Service Note No. XIII.] Mr. GiLBERT recurred to the subject of Mr. Russell’s paper of the preceding meeting, and dissented from the view advanced by Mr. Antisell in regard to the origin of pumice. Mr. ANTISELL announced that he would discuss the matter more fully at some future meeting. 250TH MEETING. Marcu 29, 1884. Vice-President MALLERY in the Chair. Forty-two members present. : The Chair announced the election to membership of Messrs. Basit Norris and WILLIAM STEBBINS BARNARD. Mr. J. S. Bruurnes spoke briefly on COMPOSITE PHOTOGRAPHY APPLIED TO CRANIOLOGY, exhibiting several composite photographs of skulls. Adult male skulls of the same race were selected for composition and were photographed in sets of from 7 to 18—front, side, and back views being separately taken. The composition was directly from the skulls and not from the photographs, Incidental mention was made of the uncertainty of measure- ments of cranial capacity by means of shot. Not only did differ- 26 PHILOSOPHICAL SOCIETY OF WASHINGTON. ent observers obtain widely different determinations from the same skull, but the same observer was not able to obtainrclosely approxi- mate results in successive determinations. Mr. G. Brown GoopE made a communication on FISHERIES EXHIBITIONS, giving a list of all international exhibitions and describing es- pecially those of Berlin (1880) and London (1883). The adminis- trative systems of these two national exhibits were contrasted, and the social and economic results of the London exhibit were ex- plained. [The substance of the paper will be published in the ex- ecutive report on the London and Berlin exhibitions. ] Mr. M. H. DoortrrLeE began a communication on MUSIC AND THE CHEMICAL ELEMENTS, but was unable to complete it before the hour for adjournment. The remaining portion was postponed until the next meeting. By unanimous consent adjournment was deferred for a few minutes in order to afford Mr. Antisell an opportunity to reply to a criticism made at the previous meeting in regard to his views on . the origin of pumice. 251st MBErTING. APRIL 12, 1884, The President in the Chair. Forty-one members and guests present. Announcement was made of the election to membership of James ARRAN Maner, Joun BeLtknap Marcou, Joun MILton Grercory, Francis Trrrany Bow es, and Witit1AmM EIMBECK. GENERAL MEETING. 27 Mr. M. H. DoouirrLe made a communication on MUSIC AND THE CHEMICAL ELEMENTS. [Abstract. ] The mathematical theory of music requires the satisfaction of : Sane, sag the equation 2* = (5) nearly ; in which, for equal temperament, x = the number of equal intervals in the octave, and y = the number of these intervals that correspond to a nearly perfect fifth ; and, for untempered music, x = the number of approximately equal intervals in the octave, and y = the number corresponding to a perfect fifth. The above equation gives log 3 Ey _ 176091 Type | art bg a nearly = 301080 7 ly; and by the method of continued fractions we obtain the succession 7 24 31 f i ti Ta coe Spr bee GF approximations > 5 777) pa" ) dio. For scales appropriate to major thirds, but disregarding fifths, we may substitute 2 for S in the above equations, and obtain HOE ts WO ae th t >) ==» oy Py OPPPOREMBORE ia). 5a! ea vibration ratio 7 : 4 (called by Ellis the subminor seventh), we may &c. For the chord having the Paes ; : Abi obtain in like manner the approximations % oF &e. Ue ahaa: : ; Since Cham Cy the first two series of approximate fractions include a common scale of twelve intervals to the octave, of which seven intervals give the fifth, and four give the major third. The first and the third of these series include a scale of five intervals to the octave, of which three constitute the major third, and four constitute the subminor seventh. There is some reason to believe that this is the scale of Japanese music, with the intervals Tea Ole ueeiney: We ; S : ca a c CAM aids a Five-tone scales have universally prevailed in early music; but it is questionable whether the vibration ratios 28 PHILOSOPHICAL SOCIETY OF WASHINGTON. have in any case involved the prime number seven. It would be interesting to know what scale best represents the songs of wild birds. There is much reason to believe that simple mathematical princi- ples underlie the phenomena of chemistry. It is not, a priori, absurd to suppose that matter in some way conforms to the prop- erties of the primes 2, 3, and 5; in which case such derivative numbers might be expected prominently to appear as prominently : : : ay Silents occur in the science of music. The fraction 75 might reasonably be expected. If all the keys of a piano should be arranged seven consecutive keys in a line, the next seven in the next line, and so on, the columns give successions of fifths. It has been shown that if the chemical elements are arranged in the order of their atomic weights in lines of seven, the columns contain elements remarkably similar to each other. We seem to have a chemical scale remarkably analogous to the ordinary musical scale. If the piano keys be arranged in lines of twelve, the columns give octaves; but nothing is devel- oped from a similar arrangement of the chemical elements, whence it may be inferred that the observed analogies are accidental, and have no true logical basis. If the intervals of the chemical scale could be supposed to cor- respond to the seven intervals of the diatonic scale, the non-appear- ance of the twelve-fold relation would be accounted for; but, while the diatonic scale may have some claim to be called natural, it is not directly established by algebraic investigation of the relations of prime numbers. Until the discovery of chemical flats and sharps, there will be insufficient reason to regard the present chem- ical scale as diatonic. Mr. Leravour illustrated the connection between tone and wave-length by means of a logarithmic spiral of base 2, the har- monic notes having radii vectores equal to multiples of the principal note. Mr. Exvxriorr said he had learned from Mr. Poole that he had endeavored, in his euharmonic organ, to produce perfect chords in all keys without temperament. | Mr. KumMMELL remarked that in modern music the,intervals of the major and minor thirds are the most important, because with- GENERAL MEETING. 29 out them there is no harmony. This is also apparent from the well- known rule in thorough-bass that a third with its fundamental note is to be treated as a complete chord. Now it happens, in dividing the octave by equal temperament into 12 equal parts, that a major third is nearly 4 and the minor third nearly 3 of these, and thus we obtain not only tolerable fifths, but also tolerable , thirds, and the requirement of thirds for harmony is approximately fulfilled. They are still better fulfilled, of course, if we divide the octave into 41 or 58 parts, as Mr. Doolittle has shown. As to the seventh harmonic, Poole and Helmholtz rightly hold that it should be and is used by instruments which can temper. It is obviously the fourth element of the chord of the dominant G, B, D, F, the F being the seventh harmonic to the G two octaves below (nearly so in equal tempcrament and exactly in natural harmony), and this chord in modern music forms the opposing harmony to the tonic chord C, E, G, in major, and C, E flat, G, in minor. Instru- ments with fixed tones like the piano-forte have to use equal tem- perament, and thus virtually reject all natural harmony except the octave. This defect is generally inappreciable in very slow move- ments, but may be noticed by a very cultivated ear. Other remarks were made by Messrs. CLARKE, Mussry, and HARKNESS. Mr. H. FarquHar read a REVIEW OF THE THEORETICAL DISCUSSION IN PROF. P. G. TAIT’S “ PNCYCLOPZDIA BRITANNICA” ARTICLE ON MECHANICS. [ Abstract. ] This article covers seventy-four quarto pages in the last edition of the Encyclopedia, and gives a thorough mathematical treatment of the subject. No innovations calling for comment—unless an extended use of the “fluxional” notation for derivative functions be so regarded—appear until near the end, where two and a half pages are devoted to a disproof of the objective reality of force, and an advocacy of the disuse of the term in scientific writing. The character of the publication, and the eminence of the author in mathematics and physics, entitle his arguments to a careful examination. 30 PHILOSOPHICAL SOCIETY OF WASHINGTON. In the first place, Prof. Tait infers that force can have no such reality as matter has, because it is to be reckoned positively and negatively—an action being opposed by reaction—while matter or mass is signless. This suggests two comments: (1), the author never questions the objective reality of space and time, of which realities it is an essential feature that to every direction or interval A-B, an equal direction or interval B—A, of opposite sign, corres- ponds; (2), the idea of a negative mass is not a self-contradictory one, and was once generally accepted. The element phlogiston was given up not because of any absurdity in ascribing levity to ma- terial substance, but because a form of matter with positive mass (oxygen), capable of explaining all the phenomena, had been actually separated and identified. Prof. Tait’s next criterion of objective reality is quantitative indestructibility, an attribute shared by time, space and matter, to which he adds energy. But the evidence of the indestructibility of energy is not of the same nature as that of the indestructibility of matter; for the latter in all its forms may be localized, and its density or elasticity measured; while the former, when stored up r “potential,” cannot be shown to possess any of the properties of energy kinetic, or any existence in space, or any objective character whatever. Prof. Tait admits this difficulty virtually, and awaits for its solution the discovery of some evidence “as yet unexplained, or rather unimagined.” All strains and other actions of a clock- weight on its supports are obviously precisely the same—or impalp- ably somewhat stronger—with the weight wound up an inch, as with it wound up a yard; and the existence of a greater “potential energy” in the latter case is to be found not in the clock, but in the mind, which requires this expression as a form in which to put its conviction that a certain greater amount of work can be obtained. Even though it be admitted that there are no other intelligible terms in which this conviction can be stated, it is clear that the indestructibility of energy is an ideal and subjective truth, and cannot, therefore, be relied on as evidence of a reality distinctively “objective.” A third point made by Prof. Tait against force is that its nume- rical expression is that of two ratios: “the space-rate of the trans- formation of energy” and “the time-rate of the generation of momentum.” These results are obtained by simple division, in an GENERAL MEETING. ol equation which expresses the fact that the work done by a body in falling the distance A is just that required to lift it through A against gravity. The fallacy involved in treating the numerical expression for force as force itself, has been well exposed by Mr. W. R. Browne (in a criticism of the same article, L. E. D. Phil. Mag. for Novem- ber, 1883); and the assumption that ratios are necessarily non- existent is even more fallacious. Were it trustworthy, Prof. Tait’s deductions would not be the only ones admissible. His equations would lead quite as conclusively to proofs of the non-objectivity of space and time (the former becoming the rate of work-units, the latter of motion-units, per unit of force), and so to a confirma- tion of the celebrated German view, that that which is universal and necessary in thought, belongs to the Subject; or they might even give mass in the form of a ratio, and hence suggest the non- objectivity of matter. Not the least of the Professor’s objections against force, it would appear, is that it is “sense-suggested.” It isa mere truism to say that no other suggestor is possible, within the domain of science, It is, perhaps, better worth while to call attention to the indubitable fact that the real, if not the avowed, ground of the objection against “action at a distance,” entertained by many physicists, is that such action is not directly suggested by sense-impressions. This is what they must mean by calling it “occult;” actions as our con- sciousness knows them, and as we can produce them, being gene- rally characterized by proximity undistinguishable from actual contact. Further, if there is any reproach in this epithet, energy is quite as open to it as any function of energy can be. In fact, our senses directly report work, in the form of nerve-disturbance, and nothing else. Force is no more truly an inference from nerve- reports testifying of energy exerted, than is matter. In fact, the ‘inference of the independent existence of matter is the less direct — and more questionable of the two. The view advocated by Mr. Browne, following Boscovich, that matter is but “an assemblage of central forces, which vary with distance and not with time” or with direction, is one of great simplicity as well as suitability to analytic treatment, and one of which no disproof is possible. The paper was discussed by Messrs. DooLirTLe and Exiorr. co bo PHILOSOPHICAL SOCIETY OF WASHINGTON. 252p MEETING. Aprit 26, 1884. Mr. Harkness in the Chair. © Thirty-eight members and guests present. Announcement was made of the election to membership of Messrs. Davip Porter Hrear and Toomas MAYHEW WoopRrvrFr. Mr. J. R. EASTMAN made a communication on A NEW METEORITE. [Abstract.] A mass of meteoric iron weighing 113 pounds was accccidently discovered in the making of an excavation at Grand Rapids, Mich- igan, and was examined by the speaker in 1883. One face shows evidence of fracture, and the greater part of the remaining surface, of fusion. A very small sample submitted to Mr. F. W. Taylor for chemical examination had a specific gravity of 7.53 and a com- position : Tron i ; r d 94.54 Nickel : : : ! 3.81 Cobalt : i i 3 .40 Insoluble (about) ‘ : 12 The stone is supposed by its holders to consist of gold and silver, and to be the buried treasure of a miser. This delusion has caused it to form the subject of a lawsuit. The communication was discussed by Messrs. Bates and F. W. CLARKE. Mr. W. H. Datu read a paper on CERTAIN APPENDAGES OF THE MOLLUSCA.* * Published in the American Naturalist, Vol. XVIII, pp. 776-778. GENERAL MEETING. 33 Mr. J. S. DILLER made a communication on THE VOLCANIC SAND WHICH FELL AT UNALASHKA OCTOBER 20, 1888, AND SOME CONSIDERATIONS CONCERNING ITS COMPOSITION. [Abstract. ] The sand is composed chiefly of crystal fragments of feldspar, augite, hornblende, and magnetite, with a considerable proportion of microlitic groundmass and a very few splinters of volcanic glass. Its mineralogical composition is that of a hornblende andesite; but the chemical analysis by Mr. Chatard shows it to contain only 52.48 per cent. of silica,—which is much more basic than the average for that group. The character of the minerals, as well as the gen- eral composition of the sand, indicated so clearly that the crater from which it must have issued was erupting hornblende-andesite, that I was led to seek an explanation for its paucity in silica. With this purpose in view, a number of volcanic sands and dusts from various parts of the world were examined and compared with the lavas to which they belong. First and most important among these is a sand from Shastina, a crater named by Captain Dutton, upon the northwestern flank of Mt. Shasta, in northern California. This sand, like that from Unalashka, is composed chiefly of crystal fragments of feldspar, augite, hornblende, and magnetite, with fragments of microlitic groundmass. Besides these, there are many pieces of hypersthene crystals and pumiceous glass. The sand con- tains 60.92 per cent. of silica, while the hornblende-andesite lava (rich in hypersthene) of Shastina, to which the sand belongs, con- tains 64.10 per cent. of silica. From these and other examples it may be stated as generally true that volcanic sand is composed essentially of crystalline frag- ments, and contains less silica than the lava to which it belongs. With volcanic dust, however, the case is different. Microscopical examination shows that it is composed chiefly of volcanic glass particles; and as far as chemical analyses have been made, they indicate that volcanic dust is more silicious than the lava to which it belongs. That volcanic sand should be crystalline and basic, and the accompanying dust vitreous and acidic, as compared with the lava 9 34 PHILOSOPHICAL SOCIETY OF WASHINGTON. to which they belong, is not merely determined by accidental cir- cumstances, but has its inception in the magma before the eruption takes place. By the process of crystallization magmas are fre- quently divided into a crystalline solid portion, and an amorphous more or less fluent portion. Basic minerals are the first to crys- tallize, so that as the process advances the amorphous remnant of the magma becomes more and more silicious. The crystals are generally thoroughly intermingled with the amorphous magma, and in the latter are accumulated nearly all of the absorbed gases under great tension, so that when the pressure is relieved it may be blown to fine silicious dust, which may be carried by the wind many miles from its source, while the solid crystalline portion will contribute chiefly to the formation of sand, and be precipitated comparatively near the crater from which it issued. In cases where no previous crystallization has taken place in the magma before it comes to violent eruption, the voleanic dust then formed will have about the same chemical composition as the lava to which it belongs. Myr. Russell has recently described an inter- esting case of this kind in the western part of the Great Basin. It appears to be generally true that if other conditions are favor- able the difference in chemical composition between volcanic sand and dust is directly proportional to the amount of crystallization in the magma before its ejection. The basic character of the Unalashka sand may be explained by supposing that the silicious portion of the magma was carried away in the form of dust. ‘ The source of this sand is supposed by the collector, Mr. Apple- gate, the Signal Service Observer at Unalashka, to have been the new crater formed last autumn, near the Island of Bogosloff, about sixty miles away. Mr. Durron spoke in commendation and amplification of Mr. Diller’s contribution to geologic philosophy. Mr. Datu described the geographic relations of the volcano from which the Unalashkan dust was presumably derived, showing the improbability of the eruption having been directly observed. He spoke also of the dis- tribution of the Aleutian volcanoes and the lithologic characters of their ejectamenta. - There ensued a general discussion of the nature and properties GENERAL MEETING. 35 of volcanic dust and of the theory which ascribes recent meteo- rologic phenomena to the dust ejected by Krakatoa. In this Messrs. Duron, Pau, W. B. Taytor, Drier, Ropinson, and Warp participated. Mr. Durron pointed out that their process of for- mation tends to give volcanic dust particles a quasi-definite size, and probably does not produce a large amount of dust fine enough for indefinite suspension. The greatest distance to which volcanic dust has been definitely ascertained to travel is eight hundred miles. Mr. Paut argued from the violence of the Krakatoan explosion its competence to charge the atmosphere at very great altitudes, and considered the fineness of the dust a sufficient explanation of its indefinite suspension. Mr. Taytor said the phenomenon to be accounted for was specially remarkable, first, for the unusual elevation of the finely- divided smoke or dust extending far above the highest cirrus clouds, or probably to twenty or thirty miles above the earth’s surface (as shown by its twilight duration); secondly, for its wide diffusion (covering a large fraction of the terrestrial atmosphere); and thirdly, for the long continuance of its suspension in the air (ex- tending over many months). Mr. Lockyer and Mr. Preece had suggested an electrical condition of the matter as favoring both its extraordinary diffusion and its equally extraordinary suspension. This hypothesis seemed to the speaker very plausible. Electricity is a phenomenon of volcanic eruption, and dust particles charged with electricity in the same sense with the earth would be repelled not only by one another, but by the earth. At thirty miles above the ground the air is not only very rare, but is practically anhydrous, and the discharge of electricity is impossible. Mr. DILLER, in response to a question by Mr. Paul, said that the microscope reveals no limit to the fineness of Krakatoan dust. The higher the magnifying power applied, the greater the number of particles visible; and this relation extends to the limits afforded by the capacity of the instrument. To more powerful microscopes, yet finer particles would presumably be visible. 36 PHILOSOPHICAL SOCIETY OF WASHINGTON. 253p MEETING. , May 10, 1884. The President in the Chair. Fifty-four members and guests present. Announcement was made of the election to membership of Messrs. JonN Murpocu, Romyn Hircucock, WiLiiam SMITH Yeates, GrorGE Perkins MERRILL, and FREDERIC PERKINS DEWEY. It was announced that a vacancy in the General Committee, occasioned by the resignation of Mr. J. J. Knox, had been filled by the election of Mr. F. W. CLarkeE. By invitation, Mr. G. H. Witiras, of Baltimore, Maryland, addressed the Society on THE METHODS OF MODERN PETROGRAPHY, first, defining the field of petrography, and second, discussing the methods of petrographic investigation. These methods dre: (1), chemical; (2), mechanical; (3), optical; (4), thermal. The chem- ical methods are quantitative and qualitative. The mechanical methods include the separation of the constituent minerals of rocks by precipitation in heavy solutions and by the use of electro-mag- nets. The optical methods include the preparation of thin sections, their examination by transmitted ordinary light, and their exam- ination by polarized light, for the determination of crystallographic system, pleochroism, and angles of extinction. The thermal methods are chiefly synthetic, consisting in the artificial production of min- eral aggregates for the purpose of determining the processes of their natural production. By the regulation of temperatures in fusion and refrigeration all varieties and all structures of basic rocks are reproduced. Acidic rocks have not been thus reproduced, and it is believed that great pressure is a condition of their genesis. Mr. Durrton spoke of the bearing of modern petrographic in- vestigations on some of the greater problems of geology. GENERAL .MEETING. 37 There followed a symposium on the question WHAT IS A GLACIER? [ Abstract. ] Mr. I. C. Russevu: In framing a definition of a glacier it is evident that we must include both alpine and continental types, and also take account of the secondary phenomena that are com- monly present. With this preamble we may define a glacier as an ice-body, originating from the consolidation of snow in regions where the secular accumulation exceeds the loss by melting and evaporation, 7. ¢., above the snow-line, and flowing to regions where loss exceeds supply, 7. e., below the snow-line. Accompanying these primary conditions, many secondary phe- nomena dependent upon environment, as crevasses, moraines, lami- nation, dirt-bands, glacier-tables, ice-pyramids, etc., may or may not be present. Mr. 8. F. Emmons: The glacier is a river of ice, possessed, like the aqueous river, of movement and of plasticity. In virtue of the latter quality it adapts itself, though more slowly, to the form of the bed in which it flows. The névé field is the reservoir, from which it derives not only its supply of ice, but the impulse which gives it its first movement. The névé is formed by the snows which accumulate in relatively wide basins above the snow-line from year to year, living through the heat of summer. Its mass may be more or less compact, according as it is thicker or thinner, and it may have a certain movement, which will be greater or less, accord- ing to the greater or less inclination of the basin; but until it moves from its wide and shallow bed into a narrower and deeper one, and thus gives outward proof of the plasticity of the ice of which it is composed, it does not become a glacier. It may be crevassed. Often a long crevasse at its upper edge gives definite proof of its movement; and this movement may cause a cracking or crevassing in other points, resulting from the unevenness of its bed. It may or may not carry blocks of rock on its surface, but these would be rare, and never in the well-defined moraine ridges that are formed upon the glacier proper. Not, however, until its form had essen- tially changed to fit the bed in which it flows should it be considered to ee a glacier proper. 38 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. W J McGee: The phenomena of glacier ice and névé ice appear to belong to a graduating series; and in eonsequence the two phases can only be arbitrarily discriminated. Any classifica- tion depending upon coincidence of the loci of apparent transition from the first phase to the second with oct of sudden constriction or abrupt acclivity in the valley is artificial and incompetent, since such coincidence is fortuitous; the classification depending upon the ability of the second phase to sustain bowlders upon its surface is superficial and incompetent (provided such ability be due to density of the ice), since the sub-surface density of the névé, being determined by its age and the pressure of the superincumbent mass, must, in some portions, equal the surface density of the gla- cier; and the classification depending upon rate of motion is equally incompetent, since motion is common to the entire ice-mass, and. abruptly varies only where conditions of glacier-bed are suddenly variant. Arbitrary diagnostic characters may and should be, how- ever, agreed upon by consense among glacialists. Perhaps the most satisfactory line of demarkation detectable is the snow-line, above which superficial débris is buried by precipitation, and below which it is exposed by ablation. Mr. W. H. Datu: It is proper to discriminate masses of ice moving in a definite direction from the immense fields of ice which are practically stationary. The term “glacier” should be restricted to the former. A glacier is a mass of ice with definite lateral limits, with motion in a definite direction, and originating from the compacting of snow by pressure. Moraines are not diagnostic; and the definition should not include those masses of arctic ice which, by reason of their low temperature, are fixed in position. Mr. T. C. CoaAmBerytin: Nomenclature is a matter of conveni- ence. When subjects rise into familiar thought and frequent reference brevity of expression calls for specific names. But terms arising thus from a natural demand are not closely discriminative. Hard and fast lines of demarcation do not prevail in nature, but rather gradations of character. Were it otherwise names of sharply- defined application could be more freely used. The terms névé and glacier doubtless originated to satisfy the convenience of guides and travelers, and were without strict scientific application. In attempt- ing to give them scientific definition, I think we shall,fail of satis- faction by making them structural terms. The better distinction GENERAL MEETING. 39 is genetic. There is an area of growth and an area of waste to every glacier, and the distinct recognition of the two in quaternary glaciers is likely to rise to some importance. Superficially the area of growth coincides with the névé; the area of waste is that of the ‘glacier proper. From every annual snow-fall there remains, at the time of maximum summer melting, a remnant that feeds the gla- cier. This is the névé for that year. The area may be greater or less in different seasons. The névé-field is accurately shown only on the day of maximum waste. A contribution of much value, bearing upon the property of ice which permits glacier motion, has recently been made by Petterson, who has demonstrated, by refined experimentation, that ice, es- pecially if impure, shrinks as it approaches the melting point and becomes plastic. © Mr. C. E. Durron desired to reiterate the remarks of Mr. Chamberlin to the effect that definitions can rarely or never be made rigorous. Glaciers, no doubt, vary in their characteristics like almost all other groups of phenomena. There is little difficulty in recognizing a glacier when all those features which characterize it are present, and when the conditions are of the ordinary nature. But exceptional cases arise. The lower parts are sometimes want- ing and the névé alone remains, or the portion where the névé passes into the glacial stream may constitute the termination. In the latter case those who desire to be extremely precise in their phraseology might hesitate. It should seem best, whenever an occurrence is modified or defective, to use the term “glacier,” with a qualification which shall express the particular circumstancs. Remarks were also made by Messrs. GILBERT and ELLiort. 254TH MEETING. May 24, 1884. The President in the Chair. Twenty-six members and guests present. It was announced from the General Committee that after the 255th meeting, June 7, the Society would take a vacation until October 11. 40 PHILOSOPHICAL SOCIETY OF WASHINGTON. A request on behalf of the coming Electrical Exhibition at Phil- adelphia for instruments and books was communicated to the Society. Mr. H. H. Bares read the following paper on THE PHYSICAL BASIS OF PHENOMENA. If there is anything entirely disheartening, it is to see the few landmarks of human achievement disappear before the shifting current of opinion, as headlands disappear under the ceaseless buffeting of the ocean. It is no doubt a matter of poignant regret to the cherisher of ardent theological convictions to see the bulwarks of faith slowly undermined by controversy. So, also, to him who has built his convictions on supposed demonstrable and irrefragable fact, to find nothing unassailable, not even the axioms and postu- lates conceded for ages as first principles, on which the fabric of science was reared, nor the sublime inductions of Galileo and Newton, on which the modern philosophy called natural—the only fruitful philosophy which man has produced—has been founded. But the course of criticism shows that there are no first princi- ples. Nothing is unquestionable. Even the mathematic joins hands with the metaphysic. I propose briefly to examine the fun- damental grounds of mechanical philosophy, in view of the wide divergence of basal hypotheses in recent years, and especially on account of the importance conferred upon certain speculations by their admission into works of standard reference and authority.* To do this aright it isnecessary to go behind the mere sub-science of mechanics to the essence and substance of things, as did the eighteenth-century philosophers succeeding Newton. The obser- vational data which have accumulated since that time by the splen- did efforts of the molecular physicists enable us to review and recast, with some promise, the primary dogmas regarding the physical basis of phenomena. It is legitimate to frame hypotheses on subjects which are still unfathomed, but which confessedly do not belong to the domain of the unknowable. The distinguished example of the authors of the vortex atom would alone justify such a conclusion. No entirely satisfactory hypothesis of the atom has yet been * Encyclopedia Britannica, 9th Ed., Articles ‘‘ Mechanics,’’ ‘‘ Measure- ment,’’ etc. GENERAL MEETING. 41 found. I do not design to discuss the vortex atom here at length; for, although it is the most successful form of the Cartesian doctrine of vortical substance, it has not been perfected, and is generally regarded rather as an example of remarkable speculative and math- ematical ingenuity, than as a discovery, corresponding with any facts of objective physics. It has insuperable difficulties, some of which have been pointed out by Clifford, and others by Clerk- Maxwell. Moreover, unparticled or continuous substance, the necessary postulate in this hypothesis, is something we not only have no experience of, but find full of inconsistencies with ex- perience, when we gain a clear conception of what it implies. Such a conception fulfills Hegel’s paradox that being and non-being are the same, since it forbids all mobility, all differentiation, as was perceived by the followers of Democritus. It simply affords an inviting basis for analytical discussion, on account of the elimina- tion of the very conditions of objective existence which make the mathematical difficulty. There are some postulates regarding substance which we may probably be permitted to assume at the outset. We may postulate its objectivity, and also its discontinuity. I have no space to review _ here the time-worn controversy between continuous and discontin- uous substance. The arguments, which are exhaustive from the metaphysical side, are as old at least as Democritus and Anaxa- goras. Suffice it to say that modern experiential philosophy has decided the battle experimentally in favor of the discontinuity of matter. The dispute only lingers in the region of the atom, where observation cannot penetrate or has not penetrated. The inability to conceive which attaches to all non-experiential affairs is encoun- tered here, coupled with the too great facility of conceiving what is superficially observed, but will not bear analysis. Thus our first impressions of substance are in favor of its continuity. It is only after much reflection that we get the idea of necessary discontinu- ity, as bound up with the exhibition of existing phenomena. But the wonderful development of the Cartesian mathematics, in con- junction with the infinitesimal calculus, and its great facility in dealing with geometrical continuities, has tacitly revived the Car- tesian idea regarding the nature of matter, as synonymous with space relations, which never reached intelligible development at the hands of its author, and wholly declined and disappeared after the 42 PHILOSOPHICAL SOCIETY OF WASHINGTON. establishment of the Newtonian philosophy, and the discovery of the discrete character of substance. In point of fact, experience would point to extreme porosity or discreteness as characteristic of substance, rather than to its oppo- site—perfect continuity. The infinite divisibility of space has nothing in the world to do with the question, though this is a con- fusion often fallen into. On the contrary, there is an infinite dis- tinction between the infinitesimal discrete units of substance, occu- pying extension by their interactivity, and the passive infinitesimal resolvability of space continuity. This is the antipodean difference between the Epicurean and the Cartesian conceptions; the former admitting of the operations of force, the free exhibition of motion, the organization of material phenomena, which are phenomena of mobility; the latter constituting a plenum, with only ideal divisions, and phenomenally as necessarily barren a negation as space itself. Substance is purely experiential. In its essence it is still incom- prehensible, because experience has not yet reached down to those recesses. We know nothing of substance except by its manifesta- tions. These manifestations are cognized by us through sense im- pressions, weighed, compared, adjusted, and analyzed in the mys- terious alembic of the mind. First impressions have enormous predominance, and are intensified by heredity of cerebral predis- position and function. We cognize substance only in bulk by direct perception, and these vast aggregations stand in thought for matter. A drop of water contains incomparably more molecules than the ocean con- tains drops; a grain of sand more particles than the earth contains grains; and it is this vast mesh of complicated forces that forms the integrated concept of matter to our apprehension. The child, before he can walk, encounters obstacles to movement, reaction to his every muscular effort, of equal measure to his own; and thus his first and profoundest convictions of objective existence are asso- ciated with resistance, opposition, repulsion. This impression of matter is so early that it remains with us as its most natural and obvious characteristic. The idea of weight is also one of the earliest experiences. This idea would not be conceivable to a denizen of the deep sea, for our first ancestor who emerged from the water gained theexperience at the cost of great struggle and enterprise. By the natural devel- GENERAL MEETING. 43 opment of muscle and function the child rears itself very early against the constant pull of our pedestal, triumphs over it with new-found energies, dances on tiptoe, and spurns the ground, but is soon content to draw the battle, to wander around a few weary years on equal terms, at length to call in the aid of a stick or crutch, and, finally, to resign the unequal contest, and sink, van- quished and satisfied, to rest in its bosom. Weight thus seemed a natural characteristic of matter until identified and generalized by Newton as a universal and especially a reciprocal property. This’ generalization transferred the property, in conception, from the naturally heavy body to a cause outside thereof, namely, the earth itself. Here the human mind relucted, for, unlike repulsion, attrac- tion is not an observational fact. All forms of tension, stress, constraint—by whatever name called—are attended in the child’s experience with an intermediary connection. ‘The string is neces- sary to pull the cart, and the action of the magnet upon the iron particles is viewed with astonishment and awe. The sense of mys- tery does not proceed so far in his case as to contemplate the equally mysterious power which makes his string differ from a rope of sand. The most profound attention of the human mind has not yet fathomed this mystery. Inertia or mass is a less obvious property, being in early obser- vation and in common apprehension bound up with weight. It was not recognized in philosophy till Galileo’s time, nor is it now by the common perception, except after training. A lady makes no scruple of asking to have a loaded car or train or vessel stopped at a given point on the instant, and reinvested with motion any number of times; and would-be inventors often contrive theoretical machines having numerous heavy reciprocating parts timed to . velocities impossible of execution. With beings under other con- ditions it is wholly different. The sword-fish, e. y., can have no conception of gravity, as he has no perception of it, but his appre- hension of inertia is finely cultivated, through the muscular sense, in setting up and modifying the rapid movements in which his © existence delights, as well as through his vivid realization of mo- mentum, in the piercing of a whale or a vessel, by which his function is so powerfully exhibited. When once realized by human perception, however, inertia becomes identified with substance as its most primary characteristic. 44 PHILOSOPHICAL SOCIETY OF WASHINGTON. The old scholastic property of impenetrability, also, is one of the superficial notions of experience, gained in the same way as that of repulsion. It seems to pertain to solids—the typical mat- ter—with approximate accuracy, though calcined plaster of Paris and water, e. g., will occupy a good share of each other’s volume, and still form a highly porous solid. But a quart receiver full of hydrogen can have a quart of carbonic acid gas deftly introduced into it as into a void space; and so can a quart of water, at ordinary temperature and pressure, according to Gmelin, without increase of volume, although water is the type of material continuity. As to impenetrability in the molecule we can predicate nothing. The evolution of heat in chemical combinations indicates penetration of volume, with reorganization of the molecule in less space; and there is no reason, except a scholastic one, why two or more molecules, or even atoms, should not occupy the same place, as admitted by the highest authority—James Clerk-Maxwell. Dimension is also a common notion, derived similarly from supe- ficial and early experience. Solids alone have figure and assign- able dimension, though liquids have fixed volume, and gases variable volume, in inverse ratio to constraint; but even solids are of vary- ing and fluctuating dimensions, according to temperature, density, etc. Solidity and liquidity are, it is well known, but mere transi- tory conditions of material aggregation, for all matter is capable, by sufficient accession of molecular motion, of assuming that hyper- bolic or expansive condition which we call gaseous, and in this state dimension and impenetrability are meaningless terms. Con- cerning dimension as a necessary attribute of the unit of mass, Clerk-Maxwell says (Encyclopedia Britannica, 9th Ed., Vol. 3, p. 37): “Many persons cannot get rid of the opinion that all matter is extended in length, breadth, and depth. This is a prejudice * * %* rising from our experience of bodies consisting of im- mense multitudes of atoms.’ That there is no necessary relation between mass and volume as there is, e. g., between mass and weight is shown to common experience by the notably different masses of a buck-shot and a pith-ball of the same dimensions, or of a cannon- ball and a child’s hydrogen balloon. A pellet of iridium equiva- lent in mass to the pith-ball might be microscopic, and, by extreme supposition, infinitesimal. We are not forced, however, to deny to GENERAL MEETING. 45 the unit of mass finite magnitude, as this would be an experiential fact when ascertained. The remaining so-called properties of matter are too obviously transitory, accidental, or derivative to require attention. Color, luminosity, opacity, transparency, sapidity, sonority, odor, texture, temperature, diathermancy, plasticity, hardness, brittleness, density, compressibility, conductivity, malleability, fusibility, solubility, and many others, are too clearly but conditions of aggregation, or else mere subjective states due to the way the complicated interactions of the primary qualities affect our senses. What are the primary qualities ? Here is where the modern method of philosophy flags, by the disappearance one by one of the experimental means of approach, as we eliminate the non-essentials. But though the substance is thus elusory, we cannot yet believe it to be illusory. Chemical and molecular physics have already gone marvellously beyond the ordinary range of sense-perception, by strictly scientific methods. Not only is the discrete character of matter established, but many data of the differentia and organization of the molecule are discovered. Here is a vast field of science in itself. From the ideal molecule, or simple couple, up through the 70 actual organized molecules of our provisional elements, then the chemical molecules of their combinations in vast numbers, discovered and undiscovered, and, lastly, the enormously complex organic molecule in infinite variety, the domain transcends in area for classification that of biologic science. The simple molecule has not yet been discovered, much less the molecular constituent, the atom, or the indivisible. It is evident, however, that the properties of matter which are essential, not differential, must reside in the atom. The philoso- phers succeeding Newton treated the atom and the elementary molecule as one, from lack of sufficient chemical knowledge. We are on a higher plane of information, but their method is not nec- essarily vitiated by such lack of distinction. We cannot, as before said, attribute @ priori to the atom dimen- sion or figure, though we postulate it to aid conception. As the atom is an absolute unit, there is incongruity in finally assigning to it such relative attributes, which are but matters of comparison and degree. There are properties, however, which are inseparable from an absolute essence. These are the properties by which the 46 PHILOSOPHICAL SOCIETY OF WASHINGTON, essence is manifested to us. We know them provisionally as forces, in the Newtonian nomenclature. Had gaseous matter neither weight nor mass, we could not know of its existence. But these attributes are so constant in matter that we estimate its quantity in terms of them and have no other exact terms. Weight is the statical measure; mass the dynamical measure. And since weight and mass correspond for all substances, under all transformations, we judge that the correspondence identifies them alike with the essence. They cannot be the mere result of organization. They must belong to the ultimate atom. At this point it would seem proper to attend to a question of defi- nition. Definitions are essential to clearness, on the one hand, and a source of entanglement on the other, if we fall into the scholastic error of regarding a mere word as the coextensive symbol of an idea. Words are evolved during the imperfection of ideas, and language is still a most imperfect medium of expression. Hence, logic is not a science in the sense that mathematics is. I have used the term force. This is a word of much ambiguity of meaning. We may use it as a convenient mathematical expression fur a mere rate of change of momentum, or we may go farther and define it, as that which changes a body’s state of rest or of uniform motion in a straight line; either of which uses restricts it to only a portion of phenomena, and ignores the whole science of statics, dealing with forces in equilibrium and the phenomena of balanced stress. If we give it a more general signification, as that which changes or tends to change, or conserve, the state of motion of particles, or systems of such, either in quantity or direction, we embrace statics as well as kinematics, and get a measurably philosophical definition, if we bear in mind the proviso that we do not thereby postulate force as an entity apart from substance. And since the compound variable space and time condition which we call motion (of which rest is but a phase) is the sensible result- ant of the interaction of such discrete substance by constant rear- rangement where readjustment is free, or the potential resultant where confined, we may admit that the observed tension and per- sistence, of whatever form, is that which effects the phenomenon (though masked by infinite variety and composition), and always across the discontinuity: not as separate entities, but as modes of manifestation of the interacting and pervasive substance itself and GENERAL MEETING. 47 its only manifestations. This we call force—the inscrutable agent of phenomena—and this I take to be the true Newtonian concep- tion, as evinced by his maturest conclusions, expressed in query 31 appended to his Optics. (B. 3, 2d Ed., 1717.) So far as weight goes, it was generalized by Newton to be a reciprocal force or stress, operative without limit on the law which inheres in radial space relations—the inverse square of the dis- tance. The term operative means effective upon mass, namely, bridging the discontinuity. Gravity is the typical attractive foree— vis centripeta. The relation is mutual by the law of action and reaction, and amounts to a universal tension among particles, con- trolling all matter everywhere into orderly movements and relations. This is what we postulate from observation, on the Newtonian plan of naming simply what we see. The notion, however, of action at a distance has encountered a metaphysical difficulty in many minds, from the preconception derived from ordinary experience that all affections or stresses must proceed through an intermediary connec- tion, deemed continuous. Even Newton made concession to this prejudice in his oft-quoted letter to Bentley. That there is really no such continuity in any mode of connection known is demonstra- ble, and the notion itself that the fancied continuity of some rare effluvium could in any way aid the mechanics of the problem is chimerical. Clerk-Maxwell, moreover, has shown (Nature, Vol. 7, p- 324; Encyclopedia Britannica, Vol. 3, p. 63) that action at a distance is as necessarily implied in repulsion as in attraction, so that theories of repulsion do not aid conception. Ability or ina- bility to conceive, furthermore, is not held even by the metaphysi-: cians to be a criterion of objective truth. Such truths exist inde- pendent of the conceiving mind. The conceiving organ was evolved by experience, and conception develops with attention. The first law of motion was wholly inconceivable to the contemporaries of Galileo, and we find such instances even now. Thus, while plain truths are inconceivable until established, some utter absurdities have been deemed conceivable, as, for instance, vacuity of two dimensions. State of mind, then, is no measure of external truth.* * In this connection, to illustrate how entirely a matter of opinion or pre- judice or culture is this notion of conceivability, I quote from a letter 48 PHILOSOPHICAL SOCIETY OF WASHINGTON. The second force or manifestation of the atom, inertia,—or mass,— | unlike gravity, is not unlimited in range of agtion. As to this property matter is discrete. Mass has both a locus and a limit (being apparently dependent for dimension on multiplicity), and amounts to that incomprehensible property by which conservation of motion is maintained. Under gravity, quantity of motion varies according to relations of contiguity, but under inertia motion is conserved in direction and quantity, is modified in direction and quantity by interaction of mass with gravity, and is redistributed by interaction with repulsive force upon an indefinitely near ap- proach of particles, upon conservative principles. Its discreteness gives matter its numerical and finite character, and admits of that interplay which constitutes phenomena.* Its reality and primary written by Faraday to Dr. Playfair, in response to some inquiries of the latter about his atomic opinions: * * * “T believe in matter and its atoms as freely as most people—at least, I think so. As to the little solid particles which are by some supposed to exist independent of the forces of matter, and which in different sub- stances are imagined to have different amounts of these forces associated with or conferred upon them, * * * as I cannot form any idea of them apart from the forces, so I neither admit nor deny them. They do not afford me the least help in my endeavor to form an idea of a particle of matter. On the contrary, they greatly embarrass me; for, after taking an account of all the properties of matter, and allowing in my consideration for them, then these nuclei remain on the mind, and I cannot tell what to do with them. The notion of a solid nucleus without properties is a natural figure or stepping-stone to the mind at its first entrance on the consideration of natural phenomena; but when it has become instructed, the like notion of a solid nucleus apart from the repulsion, which gives our only notion of solidity, or the gravity, which gives our notion of weight, is to me too dif- ficult for comprehension; and so the notion becomes to me hypothetical, and, what is more, a very clumsy hypothesis.’’ (Playfair’s works, Vol. 4, p- 84.) Here we see a difficulty opposite to that usually encountered, for, while many people profess an infirmity of conception of the forces apart from the imaginary vehicle, Faraday finds the vehicle of no use as a carrier of the properties, but a positive impediment. * This property has a multiplicity of names in the Newtonian nomencla- ture, according to the varying aspect of its function. Thus, in the aspect of persistence of mass in state of rest or of motion uniform in direction GENERAL MEETING. 49 character, when once apprehended, have proved more acceptable to the imagination than has the conception of central force, and under appulsion hypotheses (with the aid of that other readily accepted property, repulsion, and certain highly artificial hypo- thetical media), it has been made to do duty in providing so-called explandtions of gravity, under its form of vis viva. It has always seemed to me that the mode of approach adopted by Boscovich was the most philosophical and rigorous of any. He viewed matter for the purposes of mathematical treatment and for investigation of its essentials, as divested of accidental and fugitive properties; and as the analytical calculus had not then become so developed as to wholly fascinate the attention of geometers with ab-, stract and ideal relations, he proceeded from prime physical data. He thus identified matter by those apparently general and charac- teristic properties recognized by Newton as the basis of mechanical philosophy in conjunction with the laws of motion. These proper- ties are, as before said, gravity, inertia, and repulsion; or, as char- acterized by function, attraction, conservation, distribution. In this view matter consists of certain loci of central forces, mutually attractive by the first property according to a variable law in the duplicate inverse ratio of distance without limit, but restricted in manifestation as to the second property to the infinitesimal locus, thereby excluding unitary dimension. Contemplating matter un- der this aspect alone, a dilemma arose. For gravity waxing by the law of inverse squares of the distance up to the focus or origin involves the consideration of infinite force and apparently of infi- nite velocity in the limit,in the supposable case of rectilinear ap- and quantity, i. e., of resistance to change of state except in conformity with motion impressed, the property is called vis imsita, which may be vis insita activa (momentum), or vis insita passiva (vis inertie of mass.) In its aspect of acquirement of a new state of motion by interaction with other forces or masses, Newton called the new state thus superposed vis impressa ; which, when the operation of acquirement has ceased, becomes again vis insita. In its aspect of persistence of mass towards uniform direction of motion under the constant deflective stress of vector central force, it is called vis centrifuga. And in its active form, conditioned by motion ac- quired, its capacity for furnishing motion from its store, either for impressing motion upon other mass, with consequent loss, or for supplying the poten- tial fund under the drain of adverse central force, is called vis viva (energy.) > 50 PHILOSOPHICAL SOCIETY OF WASHINGTON. proach, at which point the equations become unexplainable. While Euler and La Place differ in their interpretations of the result, Boscovich sought to solve the apparent absurdity and inconceiva- bility by the invention of his ingenious and complex system of alternate spheres of attraction and repulsion, or change of sign, on a very near approach, with infinite repulsion at the focus, which so loaded down and vitiated his hypothesis as to cause its rejection. This result was similar to that of Le Sage’s speculations and those of the Ptolemaic astronomers, each thus working out the falsity of his respective scheme by superadded complications to readjust the theory to the progress of criticism or of observed fact. By attributing finite magnitude to the atomic mass, however, Boscovich’s difficulty disappears, as I had the honor of pointing out before this Society some ten years ago. This may be deemed a violent hypothesis in regard to a positive discrete simple absolute, as the atom is presumed to be, but parallel difficulties inhere in any other finite supposition, as, e. g., a sphere of repulsion. Under my provisional assumption, the way out follows from an elementary proposition of Newton’s, and it does not demand the gratuitous change of law or of continuity involved in the resort of Boscovich. The movement of a gravitating particle under stress of a center of gravitative force would be in all respects as the great 18th century mathematicians have demonstrated, until the margin of the par- ticle reached the attracting center, where, if we suppose the attrac- tive virtue to prevade the particle equally throughout a certain finite volume of mass, however minute, as gravity does the mass of a sphere, the maximum of attractive force would be attained ; for, as Newton has shown, homogeneous spheres are controlled under gravity by a law of force varying directly as the mass and inversely as the squares of the distance between their center of mass and the attracting center, at all points beyond the surface, and directly as the distance between the said centers within the surface; so that, after passing the surface, the attractive center must proceed on- wards to the gravitating center of mass (relatively), not by a force increasing to infinity, but by a force decreasing to zero, after pass- ing the maximum, since it is balanced at the center by opposing stresses.** * Let M be an exaggerated particle of mass and C'a fixed center of gravi- tation external thereto. Newton proved that for all positions outside of a GENERAL MEETING. yl. A similar law of attraction prevails between two gravitative par- ticles when both are similarly endowed with finite spherical volume and mass, excluding the idea of impenetrability (which is not a necessary attribute of mass), the Newtonian law being the product of the masses divided by the product of the distances (7) ” for outside positions. gravitating homogeneous spherical mass the stress is precisely as though the whole mass thereof were concentrated at the center of said sphere, and varies directly as the mass and inversely as the square of the distance be- tween the said center and the fixed center of gravitation; 7. ¢., G ~~ M d? The maximum of gravitating force will here be at the surface, where d is minimum. He also proved that at all points within a homogeneous gravi- tating spherical concentric shell a gravitating particle is uniformly affected by balanced attractions. Hence, the stress for any smaller concentric sphere is g Sat m m being the smaller spherical mass and 7 the reduced radius. mes But since homogeneous and similar masses are as the volumes, and similar volumes are as the cubes of the homologous dimensions, m Sem 7. i oagre S IR er SR Ye The maximum of gravitating force is here also at the surface, where r is maximum. *I write the formula this way because it is possible that we have been in error all along in regarding the denominator as a radial space relation, as Mm implied when we write it a In discussing the deflection of the particle under gravity, Newton, for mathematical simplicity, treated it as governed by a fixed attracting central force, and in testing various relations found that the radial space relation gave the true path of the planetary bodies under the immense preponderating influence of the sun’s mass. The fixed center of attraction is, however, a mathematical, not a physical, condition, and can only be realized by making M =o, when we get a form of expression which does not give a law of force. I think it possible that the relation is a mere reciprocal distance relation, since the stress is mutual for the masses and each is equally distant from the other. The inverse form of the relation, moreover, may arise from our subjective way of viewing distance, as meas- ured outwardly from ourselves, since we have to go from here to yonder. It is possible to look upon the relation as really one of contiguity or near- ness, and by placing = = ¢ we get the cosmical law of gravitation as Meme. This, however, would not be a useful formula, since we are not ac- customed to expressions which attain maximum value with minimum mag- nitude. 52 PHILOSOPHICAL SOCIETY OF WASHINGTON. For positions of encroachment the law is more complicated, and forms an interesting field for mathematical discussion. Where three or more atoms are superimposed the problem becomes too complex for discussion. It is noted, however, that such compound atom, if quiescent from extreme abstraction of heat, would be in a condition of elastic equilibrium, ready to respond like a bell to the slightest disturbances. In all these cases of interpenetration the law of stress would be finite and diminishing, and if the line of encounter should chance to be a right line through their centers (a condition infi- nitely rare in actual occurrence), they would continue on or repeat according to energy of approach; while upon any other lines of approach orbital relations would supervene, in modified curves of the second order, either hyperbolic, parabolic, or elliptic, according to velocity, and with or without partial penetration, according to nearness of approach. Boscovich, however, did not adopt this solution, although within his reach. The problem of the action of a gravitative particle as controlled by an attractive center has several aspects of statement, which may be confined to four, for practical investigation. In the first, where the particle is assumed to be without mass, no discus- sion is possible, for the two suppositious points instantly assume the same locality, and end the relation. In the second, where the par- ticle is endowed with inertia but not magnitude (and the attractive locus fixed by postulate), the element of motion enters, but infinite terms appear in the equations in the limit, forbidding interpretation. Thirdly, when we attribute finite magnitude to the gravitative par- ticle for gravitative pervasion, as in actual spherical masses, no in- finite terms appear, and we get an intelligible mathematical discus- sion, with planetary results for exterior positions, and pendulum results for interior positions, as I have heretofore demonstrated ; and lastly, when both the gravitating Joct are invested with similar attributes of volume and of mass (excluding extraneous notions of ordinary collision and repulsion from the problem), the results are similar to those of the third hypothesis. I do not introduce any of the mathematical discussions here, as the dynamics of the par- ticle have been fully treated by mathematicians, though I am not aware that any of them have pursued it to physical conclusions. It is not likely, however, that there is any matter so simple as this modified Boscovichian atom; that is, which can be identified. GENERAL MEETING. 5d All the matter we know of is already compounded and highly or- ganized. The ideal simple molecule would consist of a single pair of such atoms, bound to each other in orbital relations of more or less eccentricity, including the extreme rectilineal form of simple pendulum-like oscillation through one another’s centers; and it is a most significant fact that spectroscopic observation of all incan- descent matter shows atomic matter to be in this state of transverse or orbital oscillation with inconceivable but synchronous rapidity without regard to range, according to the pendulum law of stress varying directly as the range of oscillation, discovered by Galileo. Any theory of the simple molecule must take cognizance of this observed fact. Another cognate fact is that the law of elastic cohesion manifest in all elastic tensile action—“ ut tensio sic vis” — is a parallel law of stress, as illustrated in the spring balance weigh- ing scale, the spring dynamometer, the isochronous spring governor, etc., and is a function of molecular and ultimately of atomic force and distance. If the atom is really thus characterized, the repulsion or resistant property experienced in matter becomes worthy of investigation, since it drops,out as the primitive affection or disaffection postulated by Boscovich. I have shown that it is not necessary to oscillatory motion. We must admit that the notion of rebound or recoil, in the ordinary sense, between simple atoms possesses difficulties. No less does the idea of plasticity or destruction of momenta. Con- sider what is involved in the hypothesis of two absolutely hard, rigid, unparticled, homogeneous spherical bodies of any magnitude at all, if possessed of mass, meeting on a rectilineal central line of motion. We know what would happen in case of ordinary spherical elastic masses or aggregations of molecules. Such merely undergo, first, apparent contact, then compression, deformation, strain, accu- mulation of stress, retardation of velocity, momentary arrest, accel- eration on new lines of departure, relief of strain, recovery of form, redistribution of momenta, and final resumption of uniform veloci- ties, with relative motion inverted and aggregate energy of motion unimpaired, unless permanent distortion and heat have absorbed a portion. All this complex action is involved in the term elasticity. None of this could take place with simple undifferentiated particles, unless we invent for them a mystic atmosphere or cushion of repul- sive capacity surrounding the locus, as Boscovich was forced to do 22 54 PHILOSOPHICAL SOCIETY OF WASHINGTON. by logical conclusions. Without this, contact would be absolute and instantaneous at first impact. As hardness,involves impen- etrability, absolute destruction of motion on the instant must ensue; that is, motion and no motion at consecutive instants of time; a discontinuity unknown to experience, and known to be inconsistent with the nature of motion and of time. This argument from breach of continuity is due to Leibnitz. Conversion into heat motion is excluded, heat being a mode of motion of the entire atom. More- over, the destroyed motion has to be recreated instantaneously in new directions, for destruction of energy cannot be postulated. This geometrically angular motion is also unknown to experience, for all deflected bodies pass by continuity from motion in one direc- tion into a new direction, and, so far as we can see, must do so. These discontinuities in translatory relations are therefore put aside, not because they are inconceivable, but as illogical and non-experi- ential. Simple repulsion by contact without occult intervention is a false suggestion, and we find that we get the pseudo-conception from our false observation of what occurs in the collision of sensible masses, somewhat as we make a false observation and generalization about material continuity, or about tension, from a superficial per- ception of matter; thus creating concepts from supposed experi- ence which can have no true objective counterparts. I shall recur later to a possible derivative basis for repulsion. It is remarkable that to Newton we owe the final establishment of the majority of those fundamental and universal truths which by simplicity and generality seem to touch the absolute; that is, more than to any and all other philosophers combined. Thus, of the six ultimate generalizations, four were formulated and placed on an impregnable basis by Newton: the three laws of motion and the law of gravitation. All of these were inconceivable when first pro- mulgated, were hotly controverted on the metaphysical plan, were finally established experientially, and are now generally accepted as axiomatic by the modern mind, except for sporadic reversions which appear now and then to deny their actuality and reassert their inconceivability. The remaining two universal inductions are the collective group of axioms formulating the relations of ex- tension—the only enduring remnant of the Greek philosophy—and the law of the conservation and unity of energy, unperceived in Newton’s time in its generality, though taught as a dogma by the -_— GENERAL MEETING. 00 Cartesians. These also are still held to be inconceivable by certain disciples of metaphysical methods and axiomatic by others. Suen mental attitudes should lead us to believe that simplicity has been arrived at in all these cases and the boundaries of explainable knowledge reached, where inconceivability necessarily begins. It has been said that paradox is born either of confusion of thought, or of knowledge, or confusion of statement arising out of the imperfection or subtlety of the verbal vehicle of thought. Thus, as Clerk-Maxwell points out, the celebrated arguments of Zeno of Elea, establishing the inconceivability of motion, represented in the paradox of Achilles and the tortoise, were unanswerable and un- answered until Aristotle showed, some half century later, that du- ration is continuous and incommensurable by numerical methods in the same sense that extension is. The old logical dilemma of the irresistible force encountering the immovable body was insoluble to the Greek mind, both from lack of physical knowledge and lack of verbal clearness of statement. The acute sophist knew not the nature of force, the constitution of bodies, the conservation, trans- formation, and dissipation of energy, and consequently knew not the refuge and escape from the dilemma contained in the percep- tion of the conversion of molar energy into heat energy, expansion, and dissipation. The resources of verbal subtlety and of inner consciousness failed, as they always do. Something of the same difficulty remains in modern problems, where observation and strict verification are, from the nature of the problem, inapplicable, or where the confusion arises from the still-existing imperfection of language, or, again, where generalizations, both clearly made out and clearly formulated, have not passed into the instinctive popular apprehension. The modern dilemma of the inconceiva- bility of infinite or finite space is, I take it, due to the metaphysical form of the statement. For when we reflect that the ideas of im- mensity and of infinitesimal resolvability are but abstract generali- zations of the merely relative continuities, extension, distance, and dimension, which are in their turn but abstractions of the sense- perceptions, form, translation, and volume, the statement becomes intelligible and entirely conceivable, and I think, though with deference, saves geometry; that is, the universality of that system of inductive postulates regarding the relations of extension and inferences therefrom, known as geometry to the Greek philosophy, 56 PHILOSOPHICAL SOCIETY OF WASHINGTON. but now named Euclidean by certain analysts whose so-called geometry is symbolic. Geometry is therefore able*to deal with all aspects of extension, without regard to limit, in spite of some in- firmity in the Greek method, for scale cannot affect the generality of extension relations, and abstract unconditioned space is not an entity but a mere negation, concerning which relative propositions are unintelligible. A false philosophy regarding space is at the root of all modern heresies concerning geometry and mensuration, founded in misapprehension of the Euclidean inductions or gene- ralizations.* The first law of motion is but the formulated recognition of in- ertia, which is only manifest in conjunction with motion, actively or passively. It was known to Galileo, and laid down by Descartes as a law in his Principia. It is a cosmical truth, bound up with the absolute nature of mass and the true relations of extension, which correlates the whole fabric of dynamical knowledge with rectilinear geometry, curvilinear motion being demonstrably not a simple state of conservation under inertia, but a resultant of mul- tiple forces. The simple action of mass under the first law of motion, if undisturbed, furnishes the absolute unreturning recti- lineal path which overthrows all speculation about possible ideal spaces. I here recall a book written by a learned American of Philadelphia—learned, that is, according to the mediaeval stand- ard of the colleges—and published only during the past year, en- * There are two opposite though similar forms of error in the assumptions regarding space. The first is that space is a specific or perhaps generic en- tity or objectivity per se, possessed of conditions and attributes, like sub- stance, such as dimension (in several), differentia in locality, figure, as cur- vature, etc. (hence necessarily finite), and only uncognizable by us simply for lack of perceptive faculties to correspond. This is the fundamental error, as it seems to me, of Riemann and Lobatschewsky. The second is that of the older Cartesians, who viewed space as but the mere attribute or synonym of substance, and inconceivable apart from it, so that bodies sep- arated by void space would be absolutely in contact without regard to dis- tance. Both of these speculations are purely metaphysical, and non-exper- iential, the latter resulting from the old scholastic method of syllogistic de- duction from primary postulates of verbal definition, and the former from similar inferences from the forms of the analytical logic of symbols, the use of which is still in the scholastic stage. Like Zeno’s paradox, these merely intellectual difficulties should be removable by intellectual processes. GENERAL MEETING. 57 titled “An Examination of the Philosophy of the Unknowable, as expounded by Herbert Spencer,” wherein he naively lays down the first law of motion as unintelligible except by appulsion. Motion, he says, in the absence of propulsion is inconceivable. I have no space here to reproduce the explanation evolved out of consciousness _ by this reasoner to account for the action of a ball struck by a bat after leaving the bat. It resembles in ingenuity and gratuity some of the inventions devised to explain gravity. The notable thing about it is that here, at this date, is a mind of good caliber, informed in the higher schools of learning, which is still of the mental period of Aristotle; a mind which has evidently never apprehended in- ertia, nor heard of the great contributions to knowledge made by Galileo and Newton, by which philosophy was entirely revolution- ized. The second law of motion, regarding the independence and co- existence of motions, on which we occasionally see comments in the metaphysical vein controverting its possibility, has long been established experientially, Its early experimental proof is attrib- uted to Galileo. Yet I recall a pamphlet written and published only during the last year by a learned German at Leipzig, the theme of which was that ‘the sun changes its position in space, therefore it cannot be regarded as being in a condition of rest.” This, he concludes, overthrows the entire fabric of Copernicus, be- cause the planetary orbits in such case cannot be closed. The third law of motion is but formulated reciprocal stress, in its modes of compulsion and repulsion, through which mass acts on mass to redistribute motion by what appears to be necessary law. The stress is necessarily reciprocal, since there is no point d’appui, or fixed fulcrum, in the universe. We have thus been brought to the boundary of the absolute, where all is inconceivable until found out, and where the simple data are unexplainable. All examination seems to continue to point to mass and weight as the ineffable simple insignia of sub- stance standing on this limit. We must accept something as ele- mentary fact; what shall we find more elementary? Repulsion is still debatable; for, if we make an issue between repulsion and compulsion as contradictory primary attributes of the same essence, _ or untenable in conjunction for artificiality, by far the greater dif- ficulties attach to the former, some of which I have already alluded 58 PHILOSOPHICAL SOCIETY OF WASHINGTON. to. The profound mind of Boscovich was forced to accept repul- sion as a primal quality, but in deference to the physical hypotheses of his time, he overloaded it with complication. This has been weighed in the balance of philosophical judgment and found want- ing. I have intimated that there are possible grounds for surmising that it may not be a simple property of the atom, but a mere mode of distribution of energy dependent on composition of motion of atomic mass after change of sign, 7. ¢., a mode of vis impressa after exhaustion of the space relation; for, mathematically, the hyperbolic lines of approach and recession of two atoms under the high proper motion characteristic of the atom, and on lines not directly central, would be similar, at sensible distances, in their asymptotes (which would be the practical paths), whether the deflection were due to attractive or repulsive stress, though acceleration and retardation at the passage of the infinitesimal focus would be inverted.* * It is well known that for any finite system of two particles controlled by gravity the lines of movement are closed curves of the second order, of more or less eccentricity, about the common center of gravity, which, for equal masses, would be midway. For an infinite system under the same conditions the orbits are parabolic, but for a system to which the particles enter by extraneous motion the lines of movement are hyperbolic, thus: WIG. bs Now, under repulsion, the lines of motion are seen to be similar, A B, D E, Fig. 2, being asymptotes of the hyperbolas representing the two paths at sensible distances : - GENERAL MEETING. 59 It therefore seems to me immaterial to result which of the two modes of passing the infinitesimal focus is the true one. In either case the distance at passage is infinitesimal, and the force may be as near infinity as the facts require it to be assigned. The normal or rectilineal enzounter is here excluded from supposition. In that case, under repulsive stress, as postulated by Boscovich, the recoil would be rectilineal and opposite, without breach of continuity. Under attractive stress, with finite volume of the atomic mass, penetration would ensue as before shown; but without dimension or repulsion we have an insoluble condition, although the occur- rence would be infinitely rare. Only one pair of elements is here considered. In all real encounters, whether of masses or molecules, the effect is a vast resultant, but should not be different in kind from that of the elements; that is, hyperbolic or expansive between alien systems under motion. As the number of elements ordinarily engaged could not be represented by any numerical places of arabic notation for which we have names, we see the hopelessness of stat- ing the problem mathematically. I therefore do not presume to Hr, 2. This encounter represents only one element of the molecule, of which myriads are engaged at every recoil of molecules, not to speak of solids. It is thus seen that the mesh constituting the molecule is ordinarily impen- _ etrable to other meshes. If the curve F G be allowed to represent the out- line of the molecule, the limb of the solid to which it belongs, say a buck- shot, will be represented by the Sierra Nevada, or the Andes, and its diam- eter would be measurably represented by that of the earth, as approximately shown by Sir Wm. Thompson in the case of a drop of water. 60 PHILOSOPHICAL SOCIETY OF WASHINGTON. offer this as an explanation of repulsion, and I confess that to me repulsion is in its mechanism incomprehensible. *We know the re- sult experimentally, and that is resistance to penetration, and reac- tion at insensible distances on an undefined boundary which begins prior to contact and increases in a high exponential ratio as approx- imation progresses. The contact boundary of any solid—even the smoothest and hardest—resembles the astronomical limb of Jupiter in geometrical indefiniteness. The contact transmitter in the tele- phone, the whole range of whose phenomena occurs under pressure and so-called contact of varying degrees, illustrates how relative a thing is contact. Under high velocities the distinction between solids, liquids, and even zriform bodies entirely disappears in re- spect to repulsive reaction, though this is the most sensible distine- tion between them under low velocities. We may, therefore, adopt the conclusion that if any of the ap- parently simple properties of the atom are to be thrown out as de- rivative and secondary, presumption points to repulsion as the com- plex one. We could possibly account for phenomena in a universe bound together by purely tensile stress, but most of the sensible phenomena of solids—cohesion, affinity, tenacity, etc., including nearly all of statics—remain hopelessly unattackable problems un- der a hypothesis of pure repulsion, like that of Le Sage, or Pres- ton. It is to be noted that the kinetists who freely postulate repul- sion and appulsion, without analysis, as a primordial fact, but re- luct against compulsion or tension, are forced to the invention of the most complicated and gratuitous mechanism and media to ex- plain the phenomenon of gravity, and then without attainment of result. Le Sage’s atom is too complicated, even without his suppo- sitious or extra-mundane operative machinery; and the vortex atom is but a mere analytical expression for an unproducible con- dition in a figmentary mathematical plenum. The thesis that conservation is the characteristic by which we identify objective existence will not bear the test of examination It is only in the most recent times that such a quality has heen known or imagined, and its establishment, both as to matter and energy, is justly viewed as the triumph of modern philosophy. The evocation of matter from nothing and its relegation to nothing. even by the finite will of a wizard, was ever a common and universal notion, which did not at all impair the belief in its present reality GENERAL MEETING. 61 and substantiality. We have only to go to Apuleius for this, and it is doubtful if even now the notion of the indestructibility of mat- ter is anything but a scientific conviction, for do we not see num- bers of our contemporary fellow-citizens meeting together frequently in our midst to witness feats of materialization out of nonentity by powers akin to those of the sorcerer, without an idea of incongruity ? Nor has the essentially modern doctrine of the conservation of en- ergy anything to do with the belief in its reality. Few people ap- prehend it even now. No philosopher understood it a hundred years ago. Its verity rests on a sufficiently general inductive basis, from the refined and exhaustive experiments of Joule, and the the- oretical conclusions of Mayer and Clausius, and it is accepted in the same sense that the law of gravitation is accepted. But the duality of matter and energy to the exclusion of force is a verbal shift, the assumption of which removes no difficulty. Matter, the object, remains unexplained; and energy, the phenomenon, becomes segregated and unintelligible. Energy, in fact, is but mass in phe- nomenal manifestation, being a product of triple factors, two of which—translation and speed—are not things, but variable and evanescent conditions, and, taken together, constitute motion. Mass is the absolute or persistent factor, but the evanescent character of the variable component—motion—would render the entire phe- nomenon—energy—apparitional, were it not for the distance re- lation involved in motion, which, under the same inscrutable agency which modifies and saps the motion renders it potential upon change of sign. This agency, the dynamical source of the-manifestation, being central to mass and likewise persistent and constant, renders the positive and negative potentialities of movement constantly equal, and the actual and potential energies consequently comple- mentary, from which energy gets its character of conservation. Energy cannot therefore be that other reality of existence (be- sides matter), since force is clearly the one reality at the bottom of the manifestation of both, to whose persistence and resistance to change, except through transformation, the conservation of both is due. This one reality is, in its triple aspect of causation, (1) at- traction—the source and modifier of motion; (2) inertia—the con- server of motion; and (3) repulsion—the distributer of motion; or, more correctly, in its aspect of quality: (1) vis centripeta-—the power of mutual control across distance; (2) vis insita—the power ¥ 62 PHILOSOPHICAL SOCIETY OF WASHINGTON. of persistence in state of motion impressed; and (3) the distributive power of imparting and acquiring motion by trangfer, at minimum distance, which may be called vis partitiva, the result of which is Newton’s vis impressa. Matter thus comes into the world of phe- nomena by the simple presence of other matter, permitting the exhibition of these comparisons and interactions, involving the conditions of contiguity, distance, position, translation, direction, succession or sequence, and time-rate for the continuous increments, decrements, successions, and uniformities, all bound up in the com- pound variable continuity—motion. With motion and distance comes the dependent phenomenon—energy—active and potential, which should be a constant, the numerical units of mass being con- stant throughout immensity, provided the sum of the motions, potential and actual, be constant. This the dynamical theory de- duces from the fact of central force (for without force potential motion is ridiculous), and the thesis of the conservation of energy is a dynamical truth or nothing. It is therefore all the more ex- traordinary that certain kinetists, who reluct against central force, should have selected, out of all the manifestations of the universe, the variable and conditional product—energy—to be the one reality or objectivity, aside from the undefined hypostasis—matter—as a primordial simple fact at the basis of phenomena. It has been mathematically demonstrated by Mr. Walter R. Browne (London Edinburgh and Dublin Philosophical Magazine, January, 1883, p. 35) that the conservation of energy is true if the material system is a system of central forces, and is not true if the system is any- thing but a system of central forces. In fact, the ordinary theo- retical proof of the principle of the conservation of energy assumes the forces acting to be central forces, 7. e., reciprocal stresses between units of mass, as recognized by Clausius in his Mechanical Theory of Heat. Moreover, the entire body of kinetists, who have aimed to supersede gravity or central force, have freely assumed an extra- mundane supply of motion and energy without regard to conser- vation, and it is notable that every hypothesis for this purpose yet broached involves the constant expenditure of work without re- covery, and postulates the accession of energy in infinite influx from some occult source, of which only a small portion relatively is available or manifest in observable phenomena, thus yiolating all three of the canons of philosophical ascription—true cause, sufficient GENERAL MEETING. 63 cause, and least cause. Such is the power of conception of the un- known in endeavor to explain the inconceivable known. If the dynamic hypothesis of perpetual transformation of energy could be established as a universal induction, with as much gen- erality, e. g., as the statement of the law of gravitation, it would establish and confirm that law, by Mr. Browne’s demonstration, as something more than a law, to wit, the necessary constitution of matter as a system of central forces and nothing more, substan- tially as conceived by Newton and elaborated by Boscovich. At present it is but a dynamic induction, but the theory of gravity is no more. Our appliances are material, and we can deal with mo- lar forces, but only indirectly and inferentially with those which are atomic. Conservation is indubitably true of energy in the me- chanical and molar sense, under the laws of dynamics and the per- sistence of force. It is, also, experimentally true, so far as we can trace it, of those less understood forms of energy which are mole- cular or atomic, the establishment of which was the great glory of Benjamin Thompson, Clausius, and Joule as to heat, and of a mul- titude of observers as to electrical energy. We infer it as a gen- eral truth of these energies (formerly known as imponderables, since they are not manifestations of matter in the concrete), from the fact of their convertibility with other modes of energy which are undoubtedly dynamical, and also from the intimate connection of electrical energy with one of the specific exhibitions of central atomic force—magnetism. Such clews create a warrantable pre- sumption that the phenomena in question will all ultimately be classified among the modes of atomic mass and motion, inductively as well as hypothetically. Possibly in the investigation of these evanescent modes of energy the missing simple particle may come to light. Provisionally, we are entitled to rank them among the mechanical modes of energy, as products of the same material forces, assuming, until the contrary is proved, that some form of matter is concerned in manifestations so correlated by conservation with undoubted material activities. In including the imponderables within the general dynamical law of conservation, we have to take account of the phenomenon of dissipation, first pointed out by Sir William Thompson. It is true that heat (as well as electrical energy) is strictly correlated with and interconvertible with energy of mass motion, as before 64 PHILOSOPHICAL SOCIETY OF WASHINGTON. stated, but in its final form energy seems to take leave of matter altogether, so far as our perceptions can followit, and disappear as a material phenomenon (though liable to reappear wherever matter is encountered whose particles are deficient in a like species of atomic motion with that which disappeared; which fact indicates that atomic mass is still a factor, with its inherent prop- erty of persistence and transference). The earth and all upon it is radiating heat energy away into space at the constant rate of 500° F. of absolute temperature, more or less; the sun and the visible stars at the rate of many millions of degrees. Much energy also passes off in the luminous form. Of electrical and actinic energies we know less, and of some we doubtless know nothing. This amounts to a constant drain of the dynamical supply of energy. These final forms, the radiant energies, have a remark- able specific high cosmical velocity of their own, which is a func- tion of something not material, or at least not molar. It is sup- posable that, in addition to the dynamical source of motion from central forces, and the contraction of systems in dimension which supplies dissipation, there may be an inherent and primordial store of atomic motion. The high proper motion of some of the stars, beyond what can be accounted for on dynamical principles, and the inexhaustible and enormous supply of radiant energy from the visible stars, have afforded grounds for such a surmise, but these speculations do not belong to the domain of mechanics. And here we must bear in mind that the dynamical theory, in plac- ing these assumed agencies and modes of interaction in causal relation to phenomenal motion, by no means predicates or can predicate any- thing concerning absolute motion or its cause. The lack of this dis- tinction may have proved a stumbling block to some in comprehend- ing the idea of force. Were it not for the observed dissipation of energy no system could become contracted in dimensions a particle by the interactions of material forces, nor is there now any known way by which the material system can be expanded in dimensions except by the accession of motion from extra-mundane sources, which there is no scientific mode of ascertaining. The sum of mo- tions under the action of forces remains the same, and any change would imply creation or annihilation, which is not ascribable to a material agency. Primordial dimension remains as inscrutable a fact as ever, and primordial motion an unsolved problem. GENERAL MEETING. 65 In conclusion, I know nothing of force except as a manifestation of matter, and nothing of matter except through its manifesta- tions. It is substance that interacts with substance, so far as we know, always reciprocally, and force is but the convenient transla- tion of the terminology invented by Newton to designate these several species or modes of action, in the word vis, with its appro- priate adjective. He was arraigned by the Cartesians (and virtu- ally is by their modern representatives) as the reintroducer of oc- cult qualities into philosophy, but his statement was “hypotheses non fingo,’ and to a similar charge brought against him by Leib- nitz he pertinently replied that it was a misuse of words to call those things occult qualities whose causes are occult though the qualities themselves be manifest. I have adopted gravity as the type of central inherent force— vis centripeta—but I would not thereby be understood as excluding from the category of material forces any and all other modes of tensile or constraining force which may be hereafter made out as specific, by the elucidation of such phenomena as affinity, cohesion, tenacity, elasticity, ductility, viscosity, capillarity, polarity, mag- netism, etc., now so little understood, any more than I would ex- clude any form or mode of energy which may be observed, from the category of material phenomena. The Newtonian doctrine of force would not be impaired by such discovery, and its strength lies in the fact that it as readily includes static phenomena—that despair of the kinetist, who has no imaginable hypothesis by which to range them under a form of motion—as it does kinematical phe- nomena. Statical force (Newton’s vis mortua) cannot be ignored in a theory of force. The straw that breaks the camel’s back— the very lightning that crashes through the sky—are familiar ex- amples of its power made manifest. Its reality may be exemplified by suspending two heavy balls of equal weight at equal heights— one by an elastic cord, and the other by a tense string. The dif- ference of effort required to displace the two vertically upwards, which can be measured, makes sensible the difference between the two forms of balanced statical forces. In the one case the antago- nizing force is suddenly withdrawn, and in the other gradually. Wherever strain exists—and it is everywhere—there force. is as certainly present as when it becomes manifested in a stress relieved by motion and measurable in terms of energy. 66 PHILOSOPHICAL SOCIETY OF WASHINGTON. Let us, then, give up the standard of a priori conceivability, in view of its many historical failures, and adopé as possible that which is provisionally ascertained. The “ego” and the “cogito”— Cartesian starting points—have proved barren and irrelevant in Philosophy. True Philosophy is concerned with objectivity. The data of consciousness, mainly acquired in infancy or in the womb, are blind guides. Many an ego, whose brain was his cosmos, has run through his brief subjectivity, but the order of nature endures. The same facts are continually observed, verified, recorded, and rectified, but the observers change. Their intelligent observations add to the sum of knowledge. This is all the proof we need of objectivity, and all we will get. The insoluble difficulties of Phi- losophy have disappeared one by one since the happy thought of eliminating them by observation entered. The immortals are those who have successfully applied this method. It is only where ob- servation fails that the insolubility lingers. Beyond the sphere of the knowable it will continue, in spite of introspection. How mas- terful is fact in the presence of the most intricate mental subtle- ties. The ball leaves the bat, in spite of the inconceivability. Galileo’s plummet dropped from the moving mast strikes the deck and not the water, in spite of the inconceivability. The Earth re- turns in its orbit, to the second, in spite of the sun’s rapid fall through space, and of the inconceivability. Two opposed horses can pull no more than one, in spite of the inconceivability. The guinea and the feather dropped in the exhausted receiver strike the plate together, in spite of the inconceivability. The isochro- nous pendulum swings through the widest arc in the same time as through the smallest, in spite of the inconceivability. The minute hand overtakes the hour hand, in spite of the inconceivability. The magnet draws the iron with undiminished force through all pos- sible interpositions, in spite of the inconceivability. Could an ex- ception be found, the perpetual-motion “crank” would work a greater inconceivability, by the instant contrivance of a power- generating machine. We need not aspire, therefore, to remove any of the inconceiva- bilities of the external world. We must accept them as natural to the finite comprehension, as necessary to faculties which act by comparison, and above all as evidences of objectivity. On the other hand we should avoid that opposite error of the introspective GENERAL MEETING. 67 school, of deeming that probable, or in any way connected with fact, which merely seems conceivable. I have shown that while thesimplest truths have generally proved inconceivable until found out and established by genius, the greatest absurdities have had ready currency without a doubt of their conceivability. This all mythology shows. Such rubbish as “a thing cannot act where it is not,’ and “a body cannot move where it is not,” or “a cause cannot precede its effect” —mere metaphysical assertions or subtle- ties in face of everyday fact—were stumbling blocks for ages. Such assumptions formed the basis of deduction in lieu of observa- tion, and blocked the possibility of advance. And even yet, rigid deduction from the most hare-brained premiss, if the chain of de- duction is sufficiently intricate, seems to possess fascinations over a verifiable induction, with many minds. And now, if any ask, “cui bono” to the scientist, these philosophical inquiries and intricacies when he has the vast field of unexplored data still before him to occupy him, I answer, the queries of Philosophy are not only the main-spring and final cause of science (her first fruitful daughter and handmaid), but they, consciously or uncon- sciously, dominate the methods and results of science herself. Each investigator, even though in the domain of the most abstract of the sciences, postulates more philosophy than he is aware of; and with so much the more danger to final accomplishment if he assumes his philosophical basis without examination. It is the errors of giant minds that are dangerous, by their ponderosity. The infallibility of the master, Aristotle, seemed to make investigation useless, until the rise of parallel giants, like Galileo and Copernicus, stim- ulated a new conflict of opinion. And Descartes, though harm- less from all his productions within the metaphysical domain, is dangerous by his very eminence and originality in science, which gives vogue and currency to his monumental errors. Although acquainted with the true law of motion, his scheme of matter evolved from consciousness would forbid all exhibi- tion thereof. A grand geometer, he erected a scaffold for scaling immensity, and with unparalleled penetration perceived how a purely ideal logic, if general, would represent truth in a wholly dissimilar realm of deduction, if equally general. Sirange to say, this grand and useful discovery has become the engine, in nihilistic hands, for overthrowing all the positive knowledge we 68 PHILOSOPHICAL SOCIETY OF WASHINGTON. possess—the achievements of two thousand years of human effort. Not only geometry—all that has survived to us of philosophical value from the antique world—but the basis of positive dynamics, as handed down from Galileo and Newton and Boscovich and Dalton, are apparently undermined, for all that gives them intel- lectual value—their certainty—unless an effort be made in the neglected field of philosophy. With strange inconsistency these advocates par excellence of the experiential origin of knowledge are found in the same breath promulgating as possible truth mat- ters not only non-experiential, but not representable in ideas de- rived from or verifiable by experience, and avowedly originating not from inductive generalizations—the only source of knowledge— but in purely deductive processes in the old scholastic way, from logical premises of bald assumption. In a similar way, in the hands of the Greek sophist, language, a good servant, became a vicious master, and made a chaos of all ethical achievement. A remnant of knowledge, fortunately expressed, not in verbal, but diagrammatic logic—geometry—was left, but only to fall now by the hands of similar iconoclasts, armed with more potent destruc- tiveness, in its full flower and fruit of twenty centuries of unmo- lested growth. It is time, therefore, to get back to Baconian ground, and while using for its legitimate purposes the magnificent modern machinery of analytical investigation in the field of abstract continuity—ex- tension, motion, duration—not attempt to conjure with it as a source of objective revelation, which no mere machinery can be. ) (sin ¢!™), cos gf@)) (41) which is an elementary form if f (sin ¢, cos g, A ¢) is rational with respect to sin ¢, cos ¢, A ¢. In tracing this process backwards, the quantities may be dis- tinguished at the several steps by subprimes, so that we have, at the first backward step, sin (29 — ¢,) = ), while Hoiiel, in his Recueil de wie has p and p’, respectively. Other relations are Ph?) deo Of) deo GK gl") Hay Se) TC AP cy (ge), 9) oh M2) (Poh ua) HM) glo iN = SS = —————: * OO EES OO C ea oer Cie ek OO The following expressions for the nome q can now be given: 18 mn Pa aay ha 2 (_le), ey eng (58) The first form is simply Jacobi’s definition; the second gives, since (_Joo), = 2 tan 4 (_] + _Je) (59) q = cot? # (_] + _]o) (60) This is one of the best formule for computing gq, especially if the modulus does not differ much from unity. The third form may be 114 PHILOSOPHICAL SOCIETY OF WASHINGTON. used if 6 and ¢ are not very different, for in that case the algorithm of the arithmetico-geometric mean converges equally fast in both directions. If either 6 or c is very near to a, the process may con- verge in one direction so slowly that the formula becomes nearly inapplicable. The fourth form may be transformed to a new formula, which is more convenient than any given. In (52g) place ¢ = 2” _], then, since ; P= 2-1 _J5 gy = I"? _J5 pe BMF _J wee on = athe Pn+1 — (2Pie Ws 8 “_2e 8 @ we have AL oi—1 Qn—2 ple ae Ses gr aie eer i 1 a eo ae Oe { _Nn41 wae (61) Gn +1 But we have by (28) = sin(2(2h_)Pn+1—_)= i sin | or Qaiin? (OP. Dae 1 Gn . | yaa Ser C2" Dp \/ (4 ae ) If we suppose a, = 6, = 6. within the precision of the compu- tation, ¢, will be very small, yet not zero. We have then i 1 pecighec {@" Detite 1 = ttan #(_} + (2"_})n 41) Qn+1 HE i Vi 1 + sin (2n Dna s ct wae 1 — sin (2? Dn Per rn Vig: h tye (1 +8) Tig yas Vityi (142) MATHEMATICAL SECTION. 115 Oy eet +c) ar Qn +1 bn V3 (a—3) 1 2 Van aaa ee l VEG (sufficiently near) ey pee as - U Ete Para (sufficiently near) 1 ? On : = 5 / aves (sufficiently near) (62) oo Cn therefore we have by (61) 1 dat 1 2? an eee." ve Da Deltas 2 ee 2 Bi L (—*) Cn 2 == 2 —n+1 1 (an zm)? "=1(2 a? i n—1 Cn—1 : on since Cp = + (An_1 — D n_1) =7 it, ae —n+1 — Be —n+2 = 1 (2m . =)" =1(="=)" i if AS V Gx An—1 =] (2 on an 1 Ga) ee i C n—3 Cn—3 if a,» = V 4-1 An—2 G, ¢, if a,= Ya, a, (63) 2 1—P-s P—P> Pp —P>P 9-2 Q-n Sar OIC Arata (ets op” = p (72) We have then in this transformation the simplest possible case of Abel’s theorem (27); and because in ascending we pass to the square of the nome, it is called the quadric transformation. The ascending transformation is possible in real quantities if c¢ > a, for we have M(c, a) = M(a,c). Also if 6 > awe can use the descending transformation; and in either case we can, after one transformation, proceed in either direction. This may be symbolized by the following diagram bg a’ > rd ae In order to exhibit the practical nature of the formule given, I shall make the necessary aca area for the integral fe ae aa V1—sin?75sin’¢ Q if ¢ = 70° and also for tho complete integral. . Because y = sin 75° is > 7/3 we must use the ascending trans- formation. The computation for 70°sin 7° may be conveniently arranged as follows: 26 PHILOSOPHICAL SOCIETY OF WASHINGTON. 118 (e2) pe ee a va i oll Se EAE ? 6 easy am ‘(19) pus (eq Ag) ' ‘toryejnduwo0o Jo yuNows ows oy} A[Jowxe seatnbar sseooad siyy Aq o% UIS[~ Jo uoryeyndut0d oyy, B0L9IIZO = off WIS 9K) BOT CF0SZ66'6 — = («9 BOT — £81196 — = a Bo] Soy — L6S69F8'S = ((x)% +/+) = By BOT Soy 9FLECOL'O = (x) +/+) § UBq Soy PP SZ LFSL=(@e)o +1) §F 88 ‘OC FE 19 = 2 = (=)? CE0CZE6'6 = /P 80] = (w)9 SOT 11892666 = ? 80] GILFZ66'6 = / 80 | 66966860 = I1F8¢96'6 = C4 — ,,22) Ws Soy oe OL rely £56 £906696'6 = 2 US SOT Cr FS Gg LO= 4 96261966 = (4 — 4%) uls Soy P8 SOILG9= 4— 2% 86862166 = 4 UIs So 00,/00,000L= 4 0000000'0 = ” Sof | 8G%6¢96'0 = 8 SSP6F86'6 = 9 50] [=o 119 MATHEMATICAL SECTION. ‘sopnytydure Aq avy} o[duris o10Ul IBY St POYJOU SIT, OOLIZEF'O 8 =—- = 08% UST SOT GF0GG66'6 — = (~)9 Bo, — SP8L1896 — = 2 Soy BOT — . SF9FZLO'O = %-A SOT Soy PRSCIST I «= = %- Boy o% MIST Jo wolyeynduU0D cresoeg, = @aoj LGZFEEGS =O — v) Soy ZELOFEO'0 = 9 — 0 0060806°0 — = 3% 80, — Gh0SZ66'6 — = 2 80, — “ATIeva puNnoy st [BAdoyUT oyo[uu09 oy} wy} WLOAy puv ouFoM AreyMENMETdUIOD 94} VOY} oynduIOD eA, PHILOSOPHICAL SOCIETY OF WASHINGTON. 120 OOLIZEF'O = = 0% BB Boy 68F6SCL'6 — = °g So, — 66119610 =[ 807 LOE99TS'O — = 0% HS,0), SOT 68F6EEL'6 — = °¢9 BOT — 6FLEGS9F =, 218 BOT 1610G¢9z'¢ =" So] S6SFLOF'O = ("4 — BS) ue} Boy BST Oy 0, a amy 20] ocg90gs'6 = ("4 — 4) wey So] 96ETSEV'6 = “4 uey Soy “69S0L9F'0 = C6 — "d) uv} Soy “IZLF6GC'O = ‘4 wey Soy S0S61E8'6 = ( 4 — “4) ue} Soy IFS68EF'O = 4 Uey Soy o% UIs Jo woIyeyndu0~ GG T9LZ6T = GG SP 09 88 FO ¥8 FO 08 08 ‘6G FG GE 00.,,00,00002 TY GE EE "6S GF 9G8 = ‘66 1G 8GF = ‘66 1G 86F = ‘YE OOTIG = ‘ELST VIE = "9T 0¢ SOL = "6S FG GOT = Pp “A = (~)d Nd we aly Md "A at "4 "4 'd a "dA 'd d— 'd d 6EF6EEL'6 = "9 SOT = LFFG6SSL'6 = ‘0 80] OSF6EEL'6 = *9 Soy FOLIGGL'6 = ‘0 50] LGLLEGL'6 = *@ 80[ SEE6861L'6 = 'P Boy 2 I86F90L'6 = ‘9 50] 0000000°0 = » Soy CIGESIF'6 = 9 SOT ”@ Bo] PZLFLOG'O = *p 1g98coc'0 = *9 09L069¢°0 = *P €60F669'0 O6T88960 = 9 = D ‘8}BINDOV SSO] BIOJA.1OT} pus ‘esvd sTyy Ul IaSMOT St II YSNoy} ‘WAOYS oq MOU TIIM o[Bos Surpusosep oy} Aq [v1SojUI ouMNS oY} JO WOTyVynduUIOD oY, 121 MATHEMATICAL SECTION. ‘smorjouns o1jdi]]9 Jo ArOoYy oY} OUT UBaUT OITJOUIOSS-OoTJOUIYIIIE OY} JO UIYZLOSTB oy} Jo WOLJONpoOLzUL oy} Woy sadByUBApE [voTJOvAd oY] MOYs 07 JUoTOYFNs ‘odoy | ‘st YoIexs ojo[duMODUr eAogs oY], £89869 0 G818968°6 = 1—5 So] So] GZZLLEL'0 = 1-5 FO] ShEFELS'0 = 1-4 Bo] So] gggTege’Z = 1—a Soy eaBy OM ‘((),) Aq sooyo OL TLLZZIG6 = b Soy I $$Z6698'6 Qq—» So OI18LItFL0O =9—2 00608060 — = = ,@ 80] — GLESHGL6 — = *» Bol — Trr6sol6 = = *» SOT :sny} spuvzs b ourou oy} Jo uo14WeynduI0D EY, 122 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. Hau. spoke of the importance of the arithmetico-geometric mean in astronomy. . Mr. W. B. TAytor made a communication on A CASE OF DISCONTINUITY IN ELLIPTIC ORBITS * around an empty center of gravitative force. Diminution of the minor axis of the attracted body’s path (the major axis being con- stant) increases the ratio of distance at the two apses without limit, the “periapsis” continually approaching the attractive center, as long as the minor axis has a value, however small. But when this axis is made to vanish, and the motion is directly to the center of force, the body, instead of rebounding from it, as continuity would require, will pass through it, and describe an equal path on the opposite side, the orbit being at once doubled. This paper was discussed by Messrs. Bares, Caristir, Haun and others, and brought out a wide diversity of view as to the demeanor of a heavy point when coincident with an empty attract- ing center. 15TH MEETING. . DECEMBER 38, 1884. The Chairman presided. Nineteen members and guests present. Mr. M. H. DooxrrrLe made a communication on THE VERIFICATION OF PREDICTIONS. [ Abstract. ] Mr. G. K. Gilbert has published (American Meteorological Journal, 8°, Detroit ; September, 1884, pp. 166-172) a method of estimating the ratio of skill in predictions of occurrences and non- occurrences of a simple event. Adopting his notation, we have s = the sum or total number of cases, o = the number of occurrences, p= the number of predictions of occurrences, i MATHEMATICAL SECTION. ro e = the number of coincidences or verifications, } = the inference-ratio, or that part of the success which is due to skill and not to chance, and which may be called the degree of logical connection between event and prediction. Since success is proportional to each of the two fractions c c —~(gnd'—s 0 p it may be represented by their product é op ak ; The fraction {> Tepresents the ratio of random success, and 0 : : awh e ¢ therefore = verifications out of p predictions are to be ascribed to chance and must be subtracted throughout. The remainders, 0 0 0 — ‘and p— i, 8 8 represent fields which chance leaves for science to conquer; and PE ol represents the portion of each which science does conquer. Hence he We fe ee 7B DP Opa —oya— py 8 8 By another method, < = the probability that any single occurrence will be predicted in some manner. P —: 8s— c bee , 9 = the probability that any single date of non-occurrence will correspond to an unsuccessful prediction = the general probability of unskillful prediction in any case. Subtract from the probability that any single occurrence will be predicted in some manner the general probability of unskillful prediction, and we have = _ e = = the probability that any given occurrence will be skillfully predicted. 124 PHILOSOPHICAL SOCIETY OF WASHINGTON. In like manner 4 = the probability that any single prediction will be fulfilled in some manner. : = = the general probability of unpredicted occurrence; which, in case of prediction, becomes probability of fortuitous ful- fillment. > ; - = the probability that any single prediction will be fulfilled by reason of a logical connection. Since the skillful predictions are mingled indistinguishably with all the unskillful ones, and are vitiated accordingly, the value of the vitiated probability of the skillful prediction of any single occurrence may be represented by the product : c ¢ o—e (cs — op)? re (<- s— ;) x een, ™ op(s — 0)(s — p)’ as before. Prof. C. 8. Peirce (in Science, 1884, Nov. 14, Vol. IV, page 453) deduces the first of these factors as the unqualified value of 2, making no allowance for the vitiation, and tacitly assuming that an assortment of predictions is the logical equivalent of a jumble of the same predictions. He obtains his result by the aid of the supposition that part of the predictions are made by an infallible prophet, and the others by a man ignorant of the future. If Prof. Peirce had called on omnipotence instead of omniscience, and sup- posed the predictions to have been obtained from a Djinn careful to fulfill a portion of them corresponding to the data, the remainder of the occurrences being produced by an unknown Djinn at ran- dom, he would have obtained by parallel reasoning the second factor, i — se These Djinns represent, respectively, the known and unknown forces of nature, and gauge the prophet’s knowledge with principal reference to the proportion of predictions fulfilled. Prof. Peirce’s test refers principally to the proportion of occurrences predicted. THis test eliminates sins of omission; the other, sins of commission; and both are necessary to a proper estimate of the prophet’s comparative rectitude. MATHEMATICAL SECTION. 125 In the data cited by Mr. Gilbert from Finley’s tornado predic- tions, s = 2803, o= 51, p = 100, andc = 28. By Mr. Gilbert’s formula, a) cs — op “= 8(0--p —¢) — op he obtains t= 216. Prof. Peirce obtains 4= .523. I obtain 4= .142. By making s, 0, and 7 constant, and imposing conditions on p and ¢, we may obtain hypothetical data involving equal skill. Putting e = p, I infer that Mr. Finley would have manifested equal skill if he had made no false predictions of tornadoes, and, out of the 51, had predicted 7.35. Mr. Gilbert’s formula gives 11.18, and Prof Peirce’s 26.67. Putting c=o0,I infer that he would also have manifested equal skill if he had included all the 51 tornadoes by making 323.7 predictions. Mr. Gilbert’s formula gives 221.5, and Prof. Peirce’s 1364. _ Mr. Finley’s entire success in predicting tornadoes is ee = .154; op and since the portion due to skill = .142, we may infer that .923 of this success is due to skill, and only .077 to chance. On the other hand, of his success in predicting the non-occurrence of tor- nadoes, only .147 is due to skill, and .853 is due to chance. Prophecy and fulfillment are effects of a common cause. Neither causes the other. The problem, broadly stated, requires a nume- rical expression for the causal relation between two classes of phe- nomena either in co-existence or in sequence, when the presence of one corresponds sometimes to the presence and sometimes to the absence of the other, and sometimes both are absent. In case of sequence it is immaterial which is antecedent. The quantities de- noted by o and p should therefore be interchangeable. My formula responds properly to every test proposed by Mr. Gilbert. The value of 7 increases rapidly with that of c, and 126 PHILOSOPHICAL SOCIETY OF WASHINGTON. slowly with that of s, diminishes with increase of o or p, and varies between the limits 0 and 1. Skill in making false predictions is indicated by a negative value of cs — op; but the same degree of causal relation exists as when equal skill is employed in making true predictions ; and a negative value of 7 can never occur. When : : 0. : ; s = either p or 0,1 = 9? but the apparent indeterminateness van- ishes when we consider that 7 is the product of two factors, of which one = 0-and the other is indeterminate within limits. And the value of 2 is unaltered when predictions of non-occurrences are substituted for those of occurrences, and vice versa. In the latter case, write s — o for 0,s — p for p, and s—o—p+e fore; and the formula reduces to its original form. In addition to Mr. Gilbert’s tests, two others may be | In the case of predictions all falsely reported, we may write s — p for p and o — ¢ for c; and the formula becomes 4s 4? Lop — ca)? ~ op (s— 0) (8 —p)’ with a proper reversal of signs in the quantity under the exponent and no change in the value of 7. If occurrences always appear whenever they are not predicted, and never appear when they are predicted, we put c= 0 and p= s — 0, with the result tA; or the logical connection is perfect. In order that the general formula shall be properly applicable, care must be taken that the predictions are fairly homogeneous in definiteness of time and space. For illustration: if predictions that phenomena will occur in given months are examined indis- criminately with those that they will occur on given days, the result will be manifestly worthless. It has been proposed to extend the problem so as to include three or more classes of events of which one must happen and only one can happen in any case. It seems clear to me that no single numerical expression can be a proper solution of such a problem. Suppose the three classes of events, A, B, and C. By the method above given A and Not A may be examined; and all instances MATHEMATICAL SECTION. 127 involving either the prediction or occurrence of A may be excluded and B and C separately investigated. Suppose it thus ascertained that great skill has been shown in discriminating between A and Not A, and little or none in discriminating between B and C. No single numerical expression can properly comprehend these heter- ogeneous. results. Mr. Curtis showed that some of the results given by Mr. Doo- little could be independently deduced by another method. Mr. GrLBeErT noted as a defect in the formula proposed by Prof. ° Peirce, that it did not duly discourage positive predictions of rare events; and, while gratified with Mr. Doolittle’s discussion of the subject, he expressed a disappointment that no satisfactory decision as to the treatment of cases of three or more alternatives had been reached by him. After some further discussion, a communication by Mr. M. BAKER was called, but postponed, on motion of Mr. H. FarquyHar, to allow time for the consideration of & testimonial to a late asso- ciate, Mr. ALVORD. Mr. E. B. Exxiorr read the following tribute, prepared by Mr. Baker and himself: MEMORIAL. The Mathematical Section of the Philosophical Society of Wash- ington, having suffered the loss by death, on October 16th, 1884, of General BENJAMIN ALVORD, one of its founders and active workers, desires to place on record this testimonial to his worth and to the loss to this Section and to science by his death. Of his worth, one of America’s greatest mathematicians has said that he was a scientist of “real originality who had actually ex- tended the boundaries of science.” The bent of General Alvord’s mind and studies was early directed towards a purely geometrical solution of the general prob- lem of tangencies, and his reward, which it is our pleasure to chronicle, was success. Of his mathematical publications, the following is submitted as a provisionally complete list : 128 PHILOSOPHICAL SOCIETY OF WASHINGTON. LIST OF MATHEMATICAL PUBLICATIONS BY GENERAL BENJAMIN ALVORD. a 1. The tangencies of circles and of spheres. [Jn Smithsonian Contributions to Knowledge. 4°. Wash- ington, 1856, Vol. 8, Article 4, 16 pp., 9 plates. ] Also issued separately. 2. On the interpretation of imaginary roots in questions of maxima and minima. [In The Mathematical Monthly. 4°. New York, 1860, . April, Vol. 2, No. 7, pp. 237-240.] 3. Tangencies. [Jn Johnson’s New Universal Cyclopedia. 8°. New York, 1878, Vol. 4, pp. 723-4. ] 4. Mortality in each year among the officers of the army for fifty years, from 1824 to 1873, as derived from the army registers. [In Proceedings of the American Association for the Ad- vancement of Science, 23d Meeting, Hartford, August, 1874. 8°. Salem, 1875, pp. 57-59.] 5. The intersection of circles and the intersection of spheres. [Jn American Journal of Mathematics. 4°. Baltimore, 1882, March, Vol. 5, No. 1, pp. 25-44; 4 plates. ] 6. Curious fallacy as to the theory of gravitation. [Jn Bulletin of the Philosophical Society of Washington. 8°. Washington, 1883, Vol. 5, pp. 85-88.] tok special case in maxima and minima. [Jn Bulletin of the Philosophical Society of Washington. 8°. Washington, 1884, Vol. 6, p. 149.] Mr. M. Baker, in moying the adoption of this memorial by the Section, said: General Alvord’s entire life was that of the soldier, and his routine of life work did not call him in the direction of mathemati- cal study. Hence whatever he accomplished in mathematics or literature was accomplished in military surroundings and with only such facilities as barrack and camp life afford. If under these MATHEMATICAL SECTION. 129 conditions the total of his contributions to science appears small, we should bear in mind that any contribution under such circum- stances is exceptional. And to have been able, therefore, to make even a single contribution to human knowledge is to have done that which few men in any generation do and that of which any one of us might well be proud. General Alvord early became interested in the problem of tan- gencies and intersections of circles, and his chief mathematical work and fame rests on his complete and purely geometrical solu- tion of the various problems relating to this subject. His chief writings on this subject consist of the paper on Tangencies, in the Smithsonian Contributions in 1856; the article on Tangencies, in Johnson’s New Universal Cyclopedia; and the paper on intersec- tions, in the American Journal of Mathematics, March, 1882. The memorial was adopted, and the Secretary was instructed to send a copy of it to the family of the deceased. Note. The following members have assisted the Chairman and Secre- tary in the examination of abstracts of communications to the Mathematical Section : Title. Author. Third Member. The Problem of the Knight’s Tour. G. K. GiLBErt. E. B. Evxiort. Formule for Diminution of Ampli- sudevror 2 Pendulum. --—..-.2-.-. H. FarQuHar. A. 8S. CHRISTIE. The Formule for Computing the Position of a Satellite-__.___..-- A. Hatt. C. H. KUMMELL. The Quadric Transformation of El- Inptic Inteerals 222622 21._5 C.H. Kummetn. G. W. Hit. The Verification of Predictions....0M.H.Doouitrytz. M. Baker. Th ve ae' 1s EN RN ee a ee Fhe to ee ay ne a : : vid url ay ax oad W OP, mrtat rete ; Ait "” a: * ‘ % Vie? So ee i Oh pe ee mt eth tes}. y fd tA is) S ve pone 147at hae Boia: tear xii y £ — 7 i hoetyesael Via ie edit phsa3* ee Shey Got : . 7* ' ¥ aA M y eer x + Pers eee | AGty Seer) £ f f j of Pet ES fale ee ach orseteieg tet hy bo tidiepene cheese ; ) PINSES eRe” Ga ChE Rd Ase): FE > Kye Fl ee hey cb le peer aang Kp La Feat ia te 5 (hi vs \ ‘ { MM bees mE SPT RE eC aE Mu } ih , U ir? * a fc = eE Hay bel Dh aia Fai aie ‘ ® Ya f dix vy otf # 7) i itt 9 eee * elehaby) / ‘ wit) be 4 ? 7 it ‘ a ty, ' ‘vs RAGES oS aa! p as : “4 Boat AEDT Roth aa lnihys ty te . ‘ A an ” / yy a? ies ' nie ’ * soy { = ‘ * , sd - " a i E ; ‘ mh ; ) at f u ) ris i i Ad AN) 'e up Ms eu La ad RIDE 3 Page. Abbe, Cleveland: remarks on deflection of rivers — reportas Treasurer.....:... Sean Address of the President... ELAS UIT V.OY TN OUTS. cesccceccussccoccnssscscccscsenscsas Alvord, Gen. Benjamin, Death of.................. 72 — Memorial to............ Senoncnstisotecocee cooeanonsreccc 127 Antisell, Thomas: remarks on the chemical elements .......... Rhaauernane daccuasestacacamenceseennts 16 --— — poasesdsoca Annual address.. — Meeting..........008 Application of physical methods to intellec- METRIESCICIIC Oitewavasncusass sotcspevstscattocsscoces scseee 18 Are there aes centres for light- form- Aristotle, cited on atoms Atomic philosOphy.......scssesesesseesesesessesseeeeee —— The, physical and ipiaalsiedl .-Xxix, 81 Auditing committee, Appointment of....... seen = — Report Off.........cccscccoessecsesccccsscsceses ‘ 15 Babcock, Gen. O. E., Death off...............0.00008 72 Bacon, cited on atoms......... wageante Secon eedeuiealss xli Baker, Marcus: memorial to General Alvord.. 127 Barnard, W.S., Election to membership of.. 25 Bates, H. H.: communication on the physi- eal basis of phenomena..........cscseeeees oes eel) Bean, ‘I’. H., Election to membership of........ 72 Bibliography of North American geology..... 71 — — mathematical papers by Benjamin Al- RONG esesanvereerancene cnneapadeeneseeeds acces Rosia tach 128 Billings, J.S.: communication on compos- ite photography applied to craniology... 25 — exhibition of microscopes............... eaeeastes 73 — remarks on bibliography.............. Gardusteves ae — resolutions on the death of Dr. Wood- EE ULe wate athe koesctod ste aeunesaacacasd cccsusesveuseccce ako Perea EL WCHL Of -, ccnccwnvecvscdoxshcovsdrevseceres 81 — Election to membership of......... 15 Bogosloff, Voleanie dust from 34 Boutelle, C. E., Election to membership of... 18 — remarks on the deflection of rivers......... 24 Bowles, F. 'I., Election to membership of..... 26 Boyle, Robert, cited on atoMS.........c0cceeeeeeee xlvi Brown, 8. J., Election to membership of...... 72 Browne, W. R., cited on matter......... Sereprcet 31 Page. Buoys drifted by ocean currents..... ..........+ 14 Burchard, H. C.: remarks on the irrigation of the upper Missouri valley................+ 20 Burnett, S. M.: communication on separate centres for light- form- and color-percep- ELON sssaseedstewsavacecaeck cree an astaas Susataasaisetecsees ssh 72 ——w— Why the eyes of animals shine in the (ar eas 4,0 Fe ETI Be aseaeettccoeee aces 13 Calendar.......... suaaaudsacruaceeveaseusaotenaresdog.aedene xxii Case of discontinuity in elliptic orbits......... 122 Chamberlin, T. C.: communication on What 15) B SIACTON,?, cs saseeischeoeecuceclpuocgtiabocess cece 38 Chatard, 'T. M.: analysis of andesite 33 Chemical elements and musicC..............22+00 27 ——-YPeriodie Tawiofisics,sasecacossdeusasesccsece serceces. 2a Cheyne, Dr. George, cited on heredity........ Joely Christie, A. S.: communication on a form of the multinominal theorem......... aasherdsce 101 Clarke, F. W.: communication on the peri- odic law of chemical elements........... con Ala, — election to General Committee........ 36 Clerk-Maxwell, James, cited on properties OL, Matters .s5 RN et eae oes 44, 47 — — — VOrteX TINES.......0ccecceccsseceeee ebsdasaaabecee liv Clifford, Prof., cited on mind-stuff................ liii Columbian University affords the Society facilities............ nates Committee, Auditing... th — on communications, Dattes ‘one ses eves OD — —— Membership Of,.....ccccc..ccccceccecseceee Xiv, XV — — publications, Duties of................c008 sees xiii — —— Membership Of...............s000-seseee 00s xiv, XV Committees, Standing..................0+..Xil, XIV, XV Composite Sates applied to craniolo- EV cewewien “proneebetec as Pee) Concrete pr abteel in viiyarontation, sana seeeeweee 92, 101 CONSELEUTION hess cwseesesseeconavert sasaaccucce Sovessaetees vii Continents; Worms of-tssvecssssccevececs coecacacacenses 24 Craniology... eke He we Curtis, G. Bi: Seokatanicanione on es pole tions between northers and magnetic disturbances at Havana.. 25 — election to membership........ 5 — remarks on the veritiGations ‘of. fences tions... creer Sertpameccocnerie 74 Curves pine to theie evalutens ee desecceast OT Dall, W. H.: communication on certain ap- pendages of the mollusca............00 mevsesa nae 131 132 Page. Dall, W. H.: recent advances in our knowl- edge of the limpets.............06 pkinvenseahs aeouey 1k — — — What is a glacier ’?....... ploucsiiensessrewatseue 38 —remarks on Alaskan volcanoes... 34 — — — deflection Of rivers... .......eeccecesseeceveee 24 — — — Crifting Of DUOYS......scercerceccecer see cence ys a6 — — — tOFNAOEB...... ...ccscseececceceecncencees aanealave 3 Dalton, John, contribution to atomic the- GEV edcccuchracscspseusveanvsanencs spavhunsavecce xlvii, 1, lvi Darwin, Cited On GEMMULES .....cereecrereeerrees lili Death of Gen. Benjamin Kivauas ey GP 82-7 4 —— Gen, O. E. BabcCock...ccccssssrscsccscccsrsscvsece 72 —— H. W. Blair.......000 iethaseeue aecanabaten' divalaterigl — — Gen. Chas. EWing...........ccsseesceeseees assis Kite —— Gen. A. A. Humphreys.......0:0.6 vans .3, 4 — = Dr. Ji J: WOOAWANGL. cccisssccssissreoccssccecsesee 02 — — — Resolutions CONCErNiNG.......sereeeeree 75 Deceased members, List of....... .-Xxiii Deflection Of rivers.....ccccccssscesseecceee senatacneaeeh 21 Deposits of voleanic dustin the Great Basin. 18 Dewey, F. P., Election to membership of..... 36 Dilier, J. S.; communication on the voleanic sand which fell at Unalashka Oct. 20, 1883, and some considerations ee its composition.. en sdeeeusadrereey OO — Election to metabareiin ‘of deapansaceaadeencuvetamere Discontinuity in elliptic orbits...... cee ee Discussion of a concrete problem in hydro- statics proposed by Mr. G. K. Gilbert..... 101 Diversion of water-courses by the rotation OF the CAarthi....iscccvecsesscvsescosscens Saueeu se oeyesny 21 Doolittle, M. H.: communication on the verification of predictions............se+seeees 122 — —— music and the chemical elements.... 27 Dust, Volcamic..........cccccsescecccesesesreceeones seevrsvlOy Oo Dutton, C. E.: communication on the volca- noes and lava fields of New Mexico........ 76 — —— What is a glacier ?.,....cccccsscssccccssssneese 39 — remarks on the forms of continents ........ 24 — — — — Navajos as scientific observers..... 74 — — — PeCtrOZraphy.......cceccerseeeesseeceesecseracecee 36 — — — SUN-ZIOWS.......:.ceeeeeceeeee ceeneee eospies eeckcs 35 Earll, R. E., Election to membership of....... 72 Earthquake of Sept. 19.......cccccessssereeeeees Went 73 Eastman, J. R.: communication on a new WNGGOOTTEC sis. iscvaysasveccnchscconse tenses snacauveaesscre 32 ——— the Rochester (Minn.) tornado........ 3 Eimbeck, William, Election to membership Olccctnsccsatidaceeouvteapeste Ravatntny tavavsoaaveusssaese 26 Election of officers...........ssees0 evedeavasesenedhae 82, 87 —— new members....xi, 5, 10, 15, 18, 21, 25, 26, 32 36, 72, 81 Electric Lighting. .ccsrccsccccscsescsccscccccesecnscnccerse OO Elements, Periodic law Of.........:.ss000+ ceanencces 15 Elliott, E. B.: calendar for the use of the society ...... bas cesneeeuse aevadaansis in ceeunente wdaepecceeakid PHILOSOPHICAL SOCIETY OF WASHINGTON. Page, Elliott, E. B.: communication on electric Tigtin es cei cepcceesp sere Cassnneee poennt espe euacenesnean — memorial to General Alvord..............css008 — remarks on the etharmonic organ........0. —— —— irrigation of the upper Missouri WAL Ys icesdivecuacsss ae soseeassy — — — BSUD-GIOWS... ccccsccerceccesereeee dusia taxes eapone — — — tornadoes.,.........sceeeeeeee paceandeenre Saucueee Emmons, S. F.: communication on What is &) WlACISL Pics. coc sasestescdoccvensssceseusteranere — remarks on glaciers............. porwivossaasnanien Empirical formule for the diminution of amplitude of a freely-oscillating pendu- 80 28 Henne eee eeeeeereeeenes 20 17 3 seeeee of Ewing, Charles, Death of............... dapetneanaee xxiii Existing glaciers of the High Sierra of Cali- FOVTIIG toes cnaceccnvew sansco advdes vector ds teen iabese 5 Eyes of animals, why they shine in the dark.......... Snersseoeeunnene an waivakaegyl aiseatdeaeiaed Faraday cited on the nature of matter........ 5 Farquhar, Edward: remarks on ocean cur- rents... peeumned ancanvesenee, a tanneninns seuuseosisedssspaneetelQwiawae heanepaven 3 ———the late Dr. Woodwaraelt podeseontsastate ; Farquhar, Henry: communication on em- pirical formule for the diminution of amplitude of a freely-oscillating pendu- lum... mo ays aaeaue oe the ihooretiesl ‘disohinslon in Prof. Py G. Tait’s Encyclopedia Britannica article on mechanics..........-+« eabvalunelee sipplbunebemeetin — election as Secretary of the Mathemati- cal Section ........... seccsensecucel on beecsiunnWeneneas 87 — remarks on drifting of buoys........ apeeutasee 15 — report as Secretary... wicevesubeauneas xxiii Ferrel, William, cited on rotational deflee- SOOO ee eee tee eeeneeennsee we nee anennee coves 29 Finley’s tornado predictions Fisheries exhibitions............... Force, Reality of......:.....-0« be Form of the multinominal theorem........ pace) LOL Formula for the length of a seconds-pen- QUIDM scsenes s cuubkvanwdueeeeepteny Formule for computing the position of a BALCLILUC. .. ADDRESS AND RESIDENCE. Army Signal Office. 930 18th st. N. W. Care Smithsonian Institution. 1119 12th st. N. W. Navy Department. 1705 Rhode Island ave. Naval Hospital, New York city. Commissary General’s Office. 1718 H st. N. W. Treasury Department. 126 7th st. N. E. National Museum. Lanier Heights. Geological Survey. 1804 16th st. N. W. Coast and Geodetic Survey Office. 1925 1 st. N. W War Department. Geological Survey. 2222 G st. N. W. Smithsonian Institution. 1386 T st. N. W. Naval Observatory. 1828 Ist. N. W. Coast and Geodetic Survey Office. Yokohama, Japan. Gov’t Actuary, Treas. Dept. L2TOCG ste N. Wie Geological Survey. 1022 Vermont ave. Smithsonian Institution. Lake Valley, New Mexico. Lancaster, Ohio. Patent Office Library. 1915 H st. N. W. Coast and Geodetic Survey Office. Brooks Station, D. C. Army Signal Office. ATL Cist: Ns Wie Surgeon General's Office, U.S. A. The Portland. Naval Observatory. . 1450 Chapin st., College Hill. Navy Department. - U.S. 5. Albatross. Columbian University. 1434 N st. N.W. Admitted. LIST OF MEMBERS. XIX NAME. GALLAUDET, President E. M. (Ed- ward Miner) GanneETT, Mr. HENRY Ginon, Dr. ALBERT L. (Albert Leary) U.S. N. (Resigned GILBERT, Mr. G. K. (Grove Karl) Goppine, Dr. W. W. (William Whitney) Goocu, Dr. F. A. (Frank Austin) GoopE, Mr. G. Brown (George Brown) GooprELLow, Mr. EpwAarD Gore, Prof. J. H. (James How- ard Bee Mr. WALTER H. (Wal- ter Hayden) (Absent) GrReeLy, Lieut. A. W. (Adol- phus Washington) U.S. A. GREEN, Mr. BeRNARD KR. (Bern- ard Richardson) GREEN, Commander F. M. (Fran- cis Mathews) U.S. N. (Absent) GREENE, Prof. B. F. (Benjamin Franklin) (Founder: absent) GREENE, Capt. FRANCIs V. (Fran- cis Vinton) U.S. A. (Absent) Gresory, Dr. Jonn M. (John Milton) GUNNELL, Francis M., M. D., U. ue. Hains, Col. Pxrrer C. Conover) (Peter Hains, Mr. Roperr P. (Robert Peter) Hatt, Prof. Asarpg, U.S. N. (Founder) ; Hatt, Mr. Asapu, JR. Haxwocr, Dr. WILLIAM Hampson, Mr. THomMAS Harkness, Prof. WiLu1AM, U.S. N. (Founder) ADDRESS AND RESIDENCE. Deaf Mute College, Kendall Green. Geological Survey. 1881 Harewood ave., Le Droit Park. Geological Survey. 1424 Corcoran st. : Government Hospital for the In- sane. Geological Survey. 825 Vermont ave. National Museum. 1645 TE st. IN. W.- Coast and Geodetic Survey Office. Columbian University. 1305 Q st. N. W. Denver, Colorado. Army Signal Office. 1914 Gst N. W. 1738 N st. N. W. Navy Department. West Lebanon, N. H. West Point, N. Y. 15 Grant Place. 600 20th st., N. W. Engineer’s Office, Potomac Riy. Improvement, 2136 Pa. ave. 1824 Jefferson Place. Patent Office. 1714 18th st. N. W. Naval Observatory. 2715 N st. N. W. Yale College Observatory, New Haven, Conn. 2715 N st. N. W. Geological Survey. Geological Survey. 504 Maple ave., Le Droit Park. Naval Observatory. Cosmos Club, 23 Madison Place. s o ~» Rx} = g Le < xx PHILOSOPHICAL SOCIETY OF WASHINGTON. NAME. Hassuter, Dr. FERDINAND A. (Ferdinand Augustus) (Absent) Haypen, Dr. F. V. (Ferdinand Vandeveer) (Founder: absent) Hazen, Prof. H. A. (Henry Allen) Hazen, Gen. W. B. (William Babcock) U.S. A. Heap, Maj. D. P. (David Porter) Hensuaw, Mr. H. W. (Henry Wetherbee) HiteGarp, Mr. J. KE. (Julius Eras- mus) ( (Founder) Hitt, Mr. G. W. (George Wil- liam) Hircucock, Mr. Romyn Hopexins, Prof. H. L. (Howard Lincoln) Hoven, Prest. EDWARD SINGLE- TON (Absent Hoimes, Mr. W. H. (William Henry) Howe t, Mr. Epwin E. (Edwin Eugene) (Absent) Ipprnes, Mr. JosrerH P. (Joseph Paxson) JameEs, Rev. OwEn (Absent) JENKINS, Rear Admiral THoRN- ton A. (Thornton Alexander) WS: oN. (Founder JOHNSON, Burges) B. (Arnold Jounson, Dr. JosePH TABER Jounson, Mr. WILLARD D. (Will- ard Drake) (Absent) Jounston, Dr. W. W. (William Waring) KavurrMann, Mr. 8. H. (Samuel Hays) Keirn, Mr. R. (Reuel) Kerr, Mr. Marx B. (Mark Brickell) Kipper, Dr. J. H. (Jerome Henry) ADDRESS AND RESIDENCE. Santa Afia, Los Angeles Co., Cal. Geological Survey. 1805 Arch st., Phila., Pa. P. O. Box No. 427. 1416 Corcoran st. Army Signal Office. 1601 K st. N. W. Light House Board, Treas. Dept. 1618 Rhode Island ave. Bureau of Ethnology. 13 Iowa Circle. L739" st. Ne WV. Nautical Almanac Office. 314 Indiana ave. N. W. National Museum, or P. O. Box 630. Columbian University. 627 N st. N. W. University of California, Berkeley, Cal. Geological Survey. 1100 O st. N. W. 48 Oxford st., Rochester, N. Y. Geological Survey. 1028 Vermont ave. Seranton, Pa. 2115 Penna. ave. N. W. Light House Board, Treas. Dept. 501 Maple ave., Le Droit Park. 926 17th st. N. W. Geological Survey. 1603 K st. N. W. 1000 M st. N. W. Nautical Almanac Office. -2219 I st. N. W. Geological Survey. 722 2ist st. N. W. Smithsonian Institution. 1816 N st. N. W. Admitted. 1880 1871 1882 1881 1884 1874 1871 1879 1884 1885 1873 1879 1874 1885 1880 1871 1878 1879 1884 1878 1884 1871 1880 | | / LIST OF MEMBERS. XXI 3 NAME. ADDRESS AND RESIDENCE. 2 z =< Kix~pourne, Lt. C. E. (Charles | War Department. 1880 Evans) U.S. A. (Absent) Kine, Dr. A. F. A. (Albert Free- | 726 18th st. N. W. 1875 man Africanus) Knox, Hon. Jonun Jay (Absent) Prest. Nat. Bank Republic, New | 1874 York city KumMELL, Mr. C. H. (Charles | Coast and Geodetic Survey Office.| 1882 Hugo) 608 Q st. N. W. Lawrence, Mr. WILLIAM 1344 Vermont ave., and 1884 Bellefontaine, Ohio. Lawver, Dr. W. P. (Winfield | Mint Bureau, Treas. Dept. 1881 Peter) 1912 1st. N. W. Lez, Dr. WILLIAM 2111 Penna. ave. N. W. 1874 1821 Ist. N. W. Leravour, Mr. Epwarp B. (Ed- | 905 O st. N. W. 1882 ward Brown) Lincotn, Dr. N.S. (Nathan Smith)) 1514 H st. N. W. 1871 Loomis, Mr. E. J. (Eben Jenks) | Nautical Almanac Office. 1880 1413 Stoughton st. N. W. Lutt, Capt. E. P. (Edward Phelps)) Navy Department. 1875 U.S. N. (Absent) 74 Cedar st., Roxbury, Mass. McGez, Mr. W J Geological Survey. 1883 1424 Corcoran st. McGuire, Mr. Frep. B. (Freder- | 1416 F st. N. W. 1879 , ick Bauders) 614 Est. N. W. McMurtriz, Prof. WiLL1aAM University of Illinois, Cham- | 1876 | (Absent) paign, Ill. | Mauer, Mr. Jamus A. (James | Geological Survey. 1884 | Arran) 21 K st. N. W. | Mauuery, Col. Garrick, U.S. A.| Bureau of Ethnology. 1875 | 1323 N st. N. W. \Mawn, Mr. B. PickmaAn (Benja- | Department of Agriculture. 1885 min Pickman) 924 19th st. N. W. \Marcou, Mr. J. B. (John Belknap)| Geological Survey. 1884 | 601 13th st. N. W. Marvin, Prof. C. F. (Charles | Army Signal Office. 1885 Frederick) 1736 13th st. N. W. Marvin, Mr. Jos. B. (Joseph | Internal Revenue Bureau. 1878 | Badger) (Absent) Wason, Prof. Or1s T. (Otis Tufton)} National Museum. 1875 1305 Q st. N. W. Tarruews, Dr. W. (Washington) |} Surg. General’s Office, U. S. A. | 1884 | U.S: A. Krtas, Gen. M. C. (Montgomery | 1239 Vermont ave. 1871 Cunningham) U.S.A. (Founder) MenDENHALL, Prof.T. C.(Thomas| Army Signal Office. 1885 Corwin) RRILL, Mr. GEorGE P. (George | National Museum. 1884 ?erkins) XXII PHILOSOPHICAL SOCIETY OF WASHINGTON. NAME. Morean, Dr. E. C. (Ethelbert Carroll) Moser, Lt. J. F. (Jefferson Frank- hin) 8. N. Murpocu, Mr. JoHn Mussery, Gen. R. D. (Reuben Del- avan) Myers, Gen. WitriaAM, U.S. A. Newcomp, Prof. Simon, U.S. N. (Founder) Nicwors, Dr. Cuarves H. (Charles Henry) (Absent) NicHortson, Mr. W. L. (Walter Lamb) (ounder) Norpuorr, Mr. CHARLES Norris, Dr. Basiu U.S. A. (Ad- sent) Nort, Judge C. C. (Charles Cooper) Oapen, Mr. Hersert G. (Herbert Gouverneur) OsporneE, Mr. J. W. (John Walter) ParkE, Gen. Jonn G. (John Grubb) U.S. A. (Founder) Parker, Dr. PETER (Iounder) Parry, Dr. CHARtEs C. (Charles Christopher) (Aésent) Pau, Mr. H. M. (Henry Martyn) PEALE, Dr. A. C. (Albert Charles) Piniine, Mr. Jamzs C. (James Constantine) (Resigned) Por, Gen. O. M. (Orlando Met- calfe) U. S. A. (Absent) PoInDEXTER, Mr. W. M. ( William Mundy) Por, Dr. B. F. (Benjamin Frank- lim) U.S.A; Powrii, Major J. W. (John Wesley) Prentiss, Dr. D. W. (Daniel Webster) PritcueTt, Prof. H. 8. (Henry Smith) (Absent) ADDRESS AND RESIDENCE. 918 E st. N. W. Coast and Geodetic Survey Office. 7 2d st. S. E. Smithsonian Institution. 1441 Chapin st., College Hill. P. O. Box 618. 508 5th st. N. W. War Department. Navy Department. 941 M st. N. W. Bloomingdale Asylum, Boule- vard and 117th st., New Mork AN. Topographer, P. O. Dept. 1822" TD stag Ws 1781 K st. N. W. Vancouver, Clarke Co., Wash. Ter. Court of Claims. 826 Connecticut ave. N. W. Coast and Geodetic Survey Office. 1324 19th st. N. W. 212 Delaware ave. N. E. Engineer Bureau, War Dept. 16 Lafayette Square. 2 Lexington Place. Davenport, Iowa. Naval Observatory. 109 ist st. N. E. Geological Survey. 1010 Mass. ave. N. W. 384 Congress st. West, Detroit, Mich. 701 15th st. N. W. 806 17th st. N. W. Surg. General’s Office, U. S. A. Geological Survey. 910 M st. N. W. 1224 9th st. N. W. Director of Observatory, Wash. University, St. Louis, Mo. | Admitted. LIST OF MEMBERS. NAME. RatuBun, Mr. RicuarD Ravené, Mr. Gustave L. (Gus- tave Louis) Ray, Lieut. P. H. (Patrick Henry) WL S., A. REeNnsHAWE, Mr. Jno. H. (John Henry) Ricuey, Dr. 8. O. (Resigned) RicksEcKER, Mr. EUGENE Rivey, Dr. C. V. (Charles Valen- tine) Ritter, Mr. W. F. McK. (Will- iam Francis McKnight) Rosinson, Mr. THomas Rogers, Mr. JosepH’ A. (Joseph Addison) (Absent) Russett, Mr. Israzt C. (Israel Cook) Russe_u, Mr. Tuomas Satmon, Dr. D. E. (Daniel Elmer) Sampson, Commander WILLIAM Tomas U.S. N. (Absent) ® Savitye, Mr. J. H. (James Ham- ilton) Scuort, Mr. Cuar.es A. (Charles Anthony) (Founder) SHELLABARGER, Hon. SAMUEL SHERMAN, Hon. JouHn SHUFELDT, Dr. R. W. (Robert Wilson) U. 8. A. (Absent) SHumway, Mr. W. A. (Willard Adams) (Resigned) SicarpD, Capt. Monreomery, U. SN. SiasBEE, Commander C. D. (Charles Dwight) U.S. N. (Ab- sent Sxinner, Dr. J. O. (John Oscar) U.S.A SMILEY, Mr. Cuas. W. (Charles Wesley) SmirH, Chf. Eng. Davin, U. S.N. ADDRESS AND RESIDENCE. Smithsonian Institution. 1622 Mass. ave. 1417 6th st. N. W. Fort Gaston, Cal. Geological Survey. The Woodmont. Geological Survey. 1323 Q st. N. W. Agricultural Department, or National Museum. 1700 18th st. N. W. Nautical Almanac Office. 16 Grant Place. Howard University. 6th st. N. W., cor. Lincoln. Naval Observatory. Geological Survey. 1424 Corcoran st. Army Signal Office. 1447 Corcoran st. N. W. Agricultural Department. 1337 15th st. N. W. Torpedo Station, Newport, R. I. 1419 F st. N. W. 1315 M st. N. W. Coast and Geodetic Survey Office. 212 Ist st. S. E. Room 23 Corcoran Building. 812 17th st. N. W. U.S. Senate. 1319 K st. N. W. Surg. Genl’s Office, U. S. A., or Box 144, Smithsonian Inst. Ordnance Bureau, Navy Dept. Navy Department. Surg. General’s Office, U. S. A. 1529 Ost. N. W. U.S. Fish Commission. 943 Mass. ave. 1330 Corcoran st. XXIII Admitted. XXIV NAME. SmitrH, Mr. Epwin SporrorD, Mr. A. R. (Ainsworth Rand) Srrearns, Mr. Rosert E. C. (Rob- ert Edwards Carter) Srone, Prof. Ormond (Absent) Taytor, Mr. F. W. (Frederick William) (Absent) Taytor, Mr. W1L1AM B. (William Bower) (Founder) Tuompson, Prof. A. H. (Almon Harris) THompson, Mr. GILBERT Topp, Prof. Davip P. (David Peck) (Absent) Toner, Dr. J. M., (Joseph Mere- dith) True, Mr. FREDERICK W. (Fred- erick William) Upton, Mr. Wm. W. (William Wirt) Upton, Prof. Winsiow (Absent) Watcott, Mr. C. D. (Charles Doolittle) Wa po, Prof. Frank (Absent) Wa ker, Mr. Francis A. (Fran- cis Amasa) (Absent) Watuine, Mr. Henry F. (Henry Francis) (Absent) Warp, Mr. Lester F. (Lester Frank) Wesster, Mr. ALBERT L. (Albert Lowry) (Absent) Weep, Mr. Walter H. (Walter Harvey) Wruitine, Mr. JAmus C. (James Clarke) WHEELER, Capt. Guo. M., U.S. A. WuirE, Dr. C. A. (Charles Abia- ther) Wuirte, Dr. C. H. (Charles Henry) C5. N WIi.uiAMs, Mr. ALBERT, Jr. PHILOSOPHICAL SOCIETY OF WASHINGTON. ADDRESS AND RESIDENCE. Coast and Geodetic Survey Office. 2024 Hillyer Place. Library of Congress. 1621 Mass. Ave. N. W. Smithsonian Institution. 1635 18th st. N. W. Leander McCormick Observa- tory, University of Vir- ginia, Va. Lake Valley, New Mexico. Smithsonian Institution. 306 C st. N. W. Geological Survey. Geological Survey. 1448 Q st. N. W. Lawrence Observatory, Amherst, | Mass. 615 Louisiana ave. National Museum. 1385 N st. N. W. 1416 F st. N. W. 1746 M st. N. W. au University, Providence, ae le Geological Survey; National Museum. Army Signal Office, Fort Myer, Va Massachusetts Institute of Tech- nology, Boston, Mass. U.S. Geological Survey, Cam- bridge, Mass. Geological Survey. 1464 Rhode Island ave. West New Brighton, Staten Isl- and, N. Y. Geological Survey. 1413 Rhode Island ave. 1802 Connecticut ave. Lock Box 92. Geological Survey. 312 Mapleave., Le'Droit Park Museum of Hygiene, 1744 G st. ye av? Geological Survey. Admitted. 1882 1882 1880 1883 1881 1872 1883 1876 1882 1885 1872 1878 1876 1884 1883 LIST OF MEMBERS. ‘si 3) < NAME. Wits, Mr. BarLey Witson, H. M. (Herbert Michael) Witson, Mr. J. ORMOND (James Ormond) Wintock, Mr. WILL1AM C. ( Will- iam Crawford) Woop, Mr. Josepu (Absent) Woop, Lt. W. M. (William Max- well) U. S. N. (Absent) Woopwarp, Mr. R. S. (Robert Simpson) Worrtman, Dr. J. L. (Jacob Law- son) Wrieut, Mr. Gro. M. (George Mitchell) Yarrow, Dr. H. C. (Harry Crécy) Yeates, Mr. W. 8. (William Smith) Ziwet, Mr. ALEXANDER ZuMBROcK, Dr. A. (Anton) LIST OF DECEASED MEMBERS. Name. Benjamin Alvord Orville Elias Babcock Theodorus Bailey Joseph K. Barnes Henry Wayne Blair . Horace Capron . : A Salmon Portland Chase Frederick Collins : A Benjamin Faneuil Craig. Charles Henry Crane Josiah Curtis Richard Dominicus Cutts Charles Henry Davis 4 Frederick William Dorr . an} Qo ADDRESS AND RESIDENCE. = = Geological Survey. 1885 2017 N st. N. W. Geological Survey. 1885 1439 Massachusetts ave. N. W. | 1873 Naval Observatory. 1880 718 21st st. N. W. Supt. Motive Power, Penn Co., | 1875 Fort Wayne, Ind. Navy Department. 1871 Geological Survey. 1883 1125 17th st. N. W. Army Medical Museum. 1885 916 14th st. N. W. Geological Survey. 1885 1319 Vermont ave. Surgeon General’s Office, U.S. A.| 1874 814 17th st. N. W. Smithsonian Institution. 1884 1008 E st. S. W. Coast and Geodetic Survey Office.| 1885 1456 Corcoran st. 455 Cst. N. W. 1875 Admitted. 1872 ‘ . - ° 1871 . ° ay yore Founder . ° - 1884 : . Founder | ‘ . s - Founder 5 3 : : 1879 . : 5 . Founder . : . : Founder 1874 1871 ° : : «. 1874 . : : : 1874 XXVI PHILOSOPHICAL Name. Alexander B. Dyer . Amos Beebe Eaton Charles Ewing Elisha Foote John Gray Foster : Leonard Dunnell Gale . . Isaiah Hanscom Joseph Henry Franklin Benjamin Hough : Andrew Atkinson Humphreys . Ferdinand Kampf Washington Caruthers Kerr Jonathan Homer Lane Oscar A. Mack ‘ Archibald Robertson Marvine Fielding Bradford Meek James William Milner Albert J. Myer . George Alexander Otis Carlile Pollock Patterson Titian Ramsay Peale Benjamin Peirce John Campbell Riley John Rodgers Benjamin Franklin ginal George Christian Shaeffer Henry Robinson Searle William J. Twining Joseph Janvier Woodward . John Maynard Woodworth Mordecai Yarnall . . SOCIETY OF SUMMARY. Active members Absent members Total Deceased members WASHINGTON. Admitted, Founder Founder 1874 Founder P 1873 : 1874 1873 ; Founder 1879 Founder 1875 1883 Founder 1872 1874 Founder 1874 Founder - Founder 5 1871 - Founder Founder : 1877 : 1872 Founder c Founder 1877 ° 1878 Founder 1874 e 1871 ad y SECRETARIES’ REPORT. XXVITI ANNUAL REPORT OF THE SECRETARIES. WASHINGTON, City, December 19, 1885. To the Philosophical Society of Washington: We have the honor to present the following statistical data for 1885. At the beginning of the year the number of active members was . : . 3 ; ; i : : , hg Bole This number has been increased by the addition of 22* new members and by the return of 3 absent members. It has been diminished by the departure of 6 members, by the death of 1, by the resignation of 5, and by the dropping of 7 for non-payment of dues. The net increase of active members has thus been . : : é y ; f 6 And the active membership is now... : : ot, ae The roll of new members is: C. F. ADAMs. H. L. HopexK ins. W. A. SHUMWAY. Car BARUS. J. P. Ipprnas. W. iH. WEED. T. M. CHATARD. B. P. MANN. BAILEY WILLIS. TF. A. Goocu. C. F. Marvin. H. M. WILson. Ree EL ANS: : T. C. MENDENHALL. J. L. WoRTMAN. WILLIAM HALLOcK. J. KF. Moser. G. M. WRIGHT. THOMAS HAMPSON. C. C. Nott. ALEX. ZIWET. G. L. RAVENE. The names of deceased members (active and absent) are: HorAcE CAPRON. F. B. Hove. W. C. KERR. T. R. Peas. There have been 16 meetings for the presentation and discussion of papers (not including the public meeting of Dec. 5); the average attendance has been 48. There have been 6 meetings of the Mathe- matical Section ; average attendance 15. In the general meetings 32 communications have been presented ; in the mathematical section 14. Altogether 46 communications have been made by 32 members and one guest. The number of members who have participated in the discussions is 41. The total number who have contributed to the scientific proceedings is 54, or 31 per cent. of the present active membership. The General Committee has held 17 meetings. Attendance below 10 on one evening only, and four times as high as 15. Average 12.2. Corresponding average last year 11.9, and in 1883 10.3, when the attendance was below 10 at five meetings. Very respectfully, G. K. GILBERT, Henry FArRQuHaAR, Secretaries. *The figures in this report have been brought down to Jan. 16, 1886, so as to correspond with the list of members. They differ somewhat from those read to the Society at the annual meeting. XXVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. REPORT OF THE TREASURER. Mr. President and Gentlemen: ° The report which I have the honor to present to you to-night covers the pecuniary transactions of the fiscal year which termi- nates with this meeting. You will see from the statement which I shall presently read that the total receipts by the Treasurer have been $1,224.04, and the total disbursements $740.02, leaving a cash balance of $484.02. These sums do not, however, represent the net income and expendi- ture for the year, since the receipts include a balance transferred by the former Treasurer, and the amount collected of unpaid dues of previous years. The payments, also, include the sum of $104.12, for unpaid debts of 1884, All the liabilities of the Society have been discharged to date, and the actual income belonging to 1885 has been $1,041.00, which includes $205.00 of dues yet outstanding. The disbursements for the same period have been $635.90, leaving a net saving for the cur- rent year of $405.10. The unpaid dues of former years which have been collected, amount to $160.00. The Government bonds which belong to the Society were at the beginning of the year exchanged for new issues of the same amounts and denominations. This was done, under authority of the General Committee, in order to obtain uniformity in the designation of the Society, the former bonds having varied from each other in that particular. The bonds consist of: — 1 $1,000 00 bond, bearing interest at 4 per cent. 1 500 00 (73 “ “cc 4 79 il! 1,000 00 a3 6c “ 4} fg Total, $2,500 00. The assets of the Society are as follows: — Cash, with Riggs & Co. 3 : $482 02 Bonds j ; ; , ! ; 2,500 00 Unpaid dues. : i : : 295 00. Total ; 2 2 ; . $3,279 02 The market value of the bonds is, of course, considerably in excess of their face value; on the other hand, a part of the “un- paid dues” will probably not be collected. I have in my possession a still ample stock of the Bulletins. A copy of Vol. VII was seut directly after its publication in February last to every member entitled to receive it, as well as to the various societies and scientific journals, at home and abroad, with which it has been customary for the Society to exchange publications. 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UVANAIVO BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON, ANNUAL ADDRESS OF THE PRESIDENT. XXXI ANNUAL ADDRESS OF THE PRESIDENT, ASAPH HALL. Delivered December 5, 1885. AMERICAN SCIENTIFIC SOCIETIES. Mr. Chairman and Fellow-Members of the Philosophical Society : The termination of the office with which you have honored me during the past year brings, in accordance with our custom, the duty of addressing you, and I have chosen for my subject American Scientific Societies. ‘The Philosophical Society of Washington is the first scientific society of which I was a member, and, having still a lively recollection of the curiosity and interest with which I watched its formation and early progress, I propose to consider briefly the history of such societies in our own country, and incidentally, some of their benefits. Nothing can be more natural than the union of men of similar tastes and thought into associations for the investigation and dis- cussion of matters that mutually interest them, and thus we see in all civilized countries the formation of societies in every branch of learning and of art. In the countries of Europe such bodies have been a long time in existence, and many of them are still in vigor- ous life. Most of these societies owe their establishment to the favor of a powerful patron, generally an emperor or a king, who was.wise enough to understand that the well-being of his people would be en- hanced by the progress of science and art. But whatever may have been the motive of their foundation, these academies of scientific men have exerted a great influence on the civilization of Europe. Such an assertion may seem doubtful to the readers of what is called history, but in fact the larger part of our civilization that is good and permanent will be found closely connected with the works and inventions of scientific men. It is these works that have changed our ideas and conception of the world in which we live, and of the universe around us. It is these works, also, that slowly but surely compel the changes of political and theological theories. History, as it is now written, deals mostly with battles and sieges, with the 3a XXXIII XXXIV PHILOSOPHICAL SOCIETY OF WASHINGTON. actions of emperors and kings, the amours of princes, and the in- trigues of courtiers and priests. These are the bubbles and froth of the social world that have attracted nearly all historical writers, but there is a growing feeling that such recitals do not contain the substantial parts of history. Who would not wish to know more of the social forces that have been at work in Europe and in our own country, and which have converted some of the most rugged and barren parts of the world into the richest and most prosperous— of the ingenious and persevering industry that brings about the greatest changes in the customs of men and in the political power of nations? These changes come from an increase of command over the forces of nature, and in our ability to make these forces work for us. Now it is the discovery and study of these forces and their modes of action that form a large part-of scientific work; and if we turn to the academies of Europe we shall find that they have a splendid history. By their encouragement of the labors and writ- ings of ingenious men, by just criticism, and by the publication of memoirs these academies take a prominent place in the history of science. It is in these enduring monuments of the human intellect, rather than in brazen statues or marble shafts, that the real glory of the race consists, The men who settled our country were separated by a great ocean and a month’s journey from the civilization and learning of Europe. They had ample work to do in building houses and roads, and in establishing themselves securely in this new world, However, they soon began to set up schools and colleges, so that the elements at least of learning might be kept alive. But the inhabitants were scattered over a great extent of country, and means of communica- tion were poor. Under these circumstances concerted action and union into societies were difficult, and a century and a half passed away before the formation of a formal scientific society. The first society of this kind that I find in our country is the American Philosophical Society of Philadelphia, organized in 1769. At that time Philadelphia was the largest and the leading city of this country, and being in a good degree free of the bitter theological quibbles and disputes that embroiled New England communities, it was better adapted for the home of a scientific society. It was also the residence of Benjamin Franklin, who appears to have taken an active part in the formation of the new society, and who became its first president. Franklin was a native of Boston, but when seven- ANNUAL ADDRESS OF THE PRESIDENT. XXXV teen years of age, having written and spoken disrespectfully of what he called “religious knaves,” and having thus provoked the enmity of influential men in his native town, he sought and found a home in a more genial climate. The new society began well. Its first _ three presidents were Benjamin Franklin, David Rittenhouse, and Thomas Jefferson. This society formulated and published an ex- cellent plan of scientific work, including a study of the native inhab- itants of the country, an examination of the ancient mounds of the Western States, and researches in geology and natural history. In 1796 it offered several prizes, with premiums ranging from fifty to one hundred dollars. The first premium offered was “ for the best system of liberal education and literary instruction adapted to the genius of the government, and best calculated to promote the gen- eral welfare of the United States, comprehending, also, a plan for instituting and conducting public schools in this country on princi- ples of the most extensive utility.” Premiums were also offered for improving the method of computing longitudes from lunar distances, for the improvement of ship pumps, for the improvement of stoves or fire-places, for the best method to prevent the premature decay of peach trees, for a treatise on native American vegetable dyes, and for the best improvement of lamps. This society published its first volume of memoirs in 1771. Among the first contributors was David Rittenhouse, the able and ingenious astronomer, and the first volume contains a very full account of the Transit of Venus that happened June 3, 1769. We find here, also, some account of im- provements in the sextant, which appears to have been independ- ently invented by Thomas Godfrey, of Philadelphia, in 1730. Franklin was an early contributor to the memoirs, his writings generally having a very practical bearing. His first paper is on the causes and cure of smoky chimneys, and occupies thirty-six quarto pages. It is an interesting paper on an important subject, much discussed at that time. A correspondent of Franklin de- clares its importance by quoting the lines— “A smoky house and a scolding wife Are two of the greatest ills in life.’’ This was followed by other papers of Franklin on the formation of the earth, the‘theory of light and heat and of magnetism, and on the manufacture of paper. Franklin thought the interior of the earth is a heavy fluid, and he imagined magnetism to be a general XXXVI PHILOSOPHICAL SOCIETY OF WASHINGTON. property of the universe, so that one might govern his course from star to star by the compass. The succeeding volymes contain sey- eral ingenious memoirs by Joseph Priestley, in some of which he expounds the theory of phlogiston, which appears to have been purely a hypothetical substance for explaining the theory of com- bustion. The volume of these memoirs published in 1825 contains a letter from Albert Gallatin, Secretary of the Treasury, under date of Marcn 25, 1807, and addressed to Mr. F. R. Hassler, of Philadelphia, relating to the survey of our coast. There is a long and interesting reply by Hassler, who gives.a full account of the methods of such a survey, with descriptions of instruments, forms for keeping the observations, making maps, and carrying on the work generally. Still later these volumes contain the memoirs of Joseph Henry on his important researches in electricity and mag- netism. ‘These papers were read in January, 1835, and published in 1837. The American Philosophical Society has published twenty- one volumes of memoirs, which contain papers of enduring interest. One feels regret that a society that began so well and which has published so much of value should stop the publication of its memoirs and seem to flag in its scientific work. Let us hope that this may be only a temporary condition. The next establishment of a scientific society in our country is that of the American Academy of Arts and Sciences in Boston. This society was chartered in 1780, James Bowdoin being the first president. The Boston society does not appear to have started under such favorable auspices as its sister society in Philadelphia, but on the other hand it has kept up its scientific work better, and is still active and efficient. Perhaps this may be owing to its prox- imity to a large and flourishing college, which has now developed into a university. The American Academy of Arts and Sciences has published fifteen volumes of memoirs. Among its distinguished members I cannot omit to mention Nathaniel Bowditch, the self- taught mathematician, who was probably the first man in our coun- try to really grasp the methods of the Mecanique Celeste. It is one of the surprises of our prolific country that it produces so many men who, it is said, read the Mecanique Celeste before they graduate from college, and it is another surprise to meet these same men in after life and be convinced from their own lips that they know but little about that great work. But Nathaniel Bowditch mastered it. These two societies, that of Philadelphia and that of Boston, are ANNUAL ADDRESS OF THE PRESIDENT. XXXVII the most widely known and they are among the best of our local societies. Many others have been established or revived recently, and some of them are doing good work. Among those which have taken a high standing by the publication of valuable memoirs is the Connecticut Academy of Arts and Sciences. Such societies deserve a hearty support, and by their encouragement and direction of local talent can render valuable service to science. But these societies are too numerous to mention here. I cannot, however, pass from the two elder societies without notic- ing in the first place the gradual cessation of their memoirs and the falling into what are styled “proceedings” for publication. It seems to me a matter of regret that this should happen. Such pub- lications are apt to degenerate into a dry account of meetings, and elections, and deaths and resignations, and lists of members. If this is all a society is able to do it may be tolerated for awhile, but it is a condition which should be outgrown. I think that keeping up a good form for printing memoirs tends to elevate the character of a society and to incite members to good works. There is another matter in connection with these two elder socie- ties which is curious and worthy of mention. Each of them had a list of foreign honorary members. It is interesting now after the lapse of a century to examine these lists, and to see what kind of men were selected for such honors, and also to see how far the judgment of the philosophers has been confirmed by time, which makes such havoc with the estimates of men. At the time of the organization of the American Philosophical Society, Euler was the jeading mathematician of Europe. He was then sixty-two years old and at the height ofhis reputation. There is hardly a branch of mathematics which Euler had not enriched by his ingenious and wonderfully prolificlabors. He had worked in the theory of numbers, in all parts of the calculus, and had laid the foundations of the cal- culus of variations. He wrote a complete treatise on dioptrics, made a laborious and valuable investigation of the lunar theory, and ap- plied mathematical theories to a very great number of physical questions. In 1766 he became blind by his incessant labors, but still continued his work. Ido not find the name of Leonard Euler in the list of the fifty-five foreign associates of the American Philosoph- ical Society. The successor of Euler as the leading mathematician of the world was Lagrange. The Mecanique Analytique was not published until 1788, but Lagrange had shown his power in a great XXXVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. number of memoirs on mathematical and astronomical questions. The Mecanique Analytique put him at the head ef all living inves- tigators in the theory of rational mechanics; and this book remains to-day a model worthy the study of every student. In fact at the present time, when so many doctors and professors seize the great analytical machine and turn out pages of elegant and trifling formule, there can be no better experience than to go back to the luminous pages of Lagrange. Here is a master whose symbols are always in subjection, and who has no need to startle us by mysterious phrases. His inventions and improvements are among the most valuable in the history of pure and applied mathematics. But the name of Lagrange is not on the list of honorary members of the American Philosophical Society. Laplace was a younger man than Lagrange, but he was fortunate in securing a good position in Paris in early life, and he immediately began that wonderful career of scientific labors that culminated in the Mecanique Celeste. The first volume of this work was published in the year seven, or in 1799. It is the methodical arrrangement and condensation of the labors of his great predecessors and colleagues of that century, together with his own remarkable investigations—a work that placed him at the head of the philosophers of his day. But his fame was not of the kind to put him on the honorary list of the American Philo- sophical Society. It may be worth while to look for one name more, that of Legendre, the ingenious and persevering mathematician who lived such a quiet and unpretentious life that we are not surprised to find his name omitted. I think this example is worthy of notice, since it shows that the scales of philosophers donot weigh men much more accurately than those of other people. But it would bea mistake to suppose that this society differed in this respect very much from others of its own time. The matter may be instructive in warning us against careless estimates of our cotemporaries, and by giving us caution in judging scientific men from their social position and rank. It may also throw light on the election to posi- tions in our scientific societies of men whose chief recommendation is a noisy and uncertain reputation. However these things may be one thing is certain: the lords, counts, and gentlemen of the hono- rary lists are dead, buried, and forgotten; but the names of the four men who could not command this distinction live in. the memories of all men of science. Omitting for the present any reference to the many scientific socie- ANNUAL ADDRESS OF THE PRESIDENT. XXXIX ties that have been organized recently I come to our national socie- ties. The earliest of these is the American Association for the Advancement of Science. The first meeting of this association was held in Philadelphia in 1848, and was called to order by Pro- fessor William B. Rogers, of Virginia, who had taken a prominent part in its formation. Only one volume of memoirs has been pub- lished by the American Association, but its annual volume of pro- ceedings has been issued with regularity. This association has em- braced among its members nearly all the prominent scientific men of the country, and it is our most complete national scientific organiza- tion. Theplan of its formation seems to have been a good one, and I think it has exerted an excellent influence by bringing into acquain- tance and sympathy men from different parts of the country. Ia recent years its character has become more popular, and under the lead of its energetic secretary its membership has reached nearly two thou- sand. During its early days this society took an active part in dis- cussing the scientific operations carried on by the General Govern- ment, and its influence in this direction seems to have been wise. With the increase in the number of members such discussions have been judiciously avoided, and even the passing of resolutions, so common in all American bodies, might perhaps better be omitted. In such large bodies there is apt to be so much confusion and dis- pute that the resolutions are made extremely vague and meaning- less or are manipulated to suit the purpose of afew. There is another danger to this society arising from its easy conditions to membership and its rapid increase of members. Our country pro- duces a large number of men and women who are born with a mis- sion. Educated in the schools and colleges, but never attaining much distinction as scholars, these people begin in their own phrase to think for themselves. The result of this thinking is often some discovery in science, and one that contravenes doctrines estab- lished by long observation and study. The questions considered are generally vast and mysterious, such as the origin of gravitation, the nebular hypothesis, and the nature of force. Having made his discovery the author wishes of course to present it to the world, and what method is more convenient than through a scientific society, admission to which is so easy. And if we admit a person to mem- bership and take his money how can we refuse to listen to his theories. Who that has had the honor of presiding over one of the sections of the American Association, in casting his eye over XL PHILOSOPHICAL SOCIETY OF WASHINGTON. the audience, has not had brought to mind the description of Dean Swift : : “The first man I saw was of meagre aspect, with sooty hands and face; his hair and beard long, ragged, and singed in several places. He had been eight years upon a project for extracting sunbeams out of cucumbers, which were to be put into phials hermetically sealed, and let out to warm the air in raw and inclement summers, He told me he did not doubt in eight years more he should be able to supply the governor’s gardens with sunshine at a reasonable rate; but he complained that his stock was low, and he entreated me to give him something as an encouragement to ingenuity, especially as this had been a dear season for cucumbers.” Now although this matter has a comical phase, it has also its serious and difficult side. No man of science wishes to suppress the opinions of others, and ingenious speculations are worthy of atten- tion, but he has a right to his own time, and should be freed from the trouble of listening to absurd projects. How this can be done with such an easy course of admission to membership I do not see. There is another hindrance to the successful operation of the Ameri- can Association which comes from the great extent of our country and the cost and difficulty of attending its meetings. To those who have ample time and means at their disposal this hindrance is not, perhaps, very great. This vigorous and generous society may need a little pruning, but on the whole its influence has been good, and every one must wish it a long and honorable life. We have another scientific organization of national character in the National Academy of Sciences, established in 1863. This is a body on a basis quite different from that of the American Associa- tion for the Advancement of Science. The National Academy was brought into existence during a great civil war, and its members were of necessity chosen from one section of the country. It was incorporated by act of Congress, and this act limited the number of its members to fifty. From the language of the act we may fairly infer that the academy was intended to be the adviser of the Gen- eral Government in matters of science. During a time of great civil commotion, when the powers of the Government were greatly extended, such a society would very naturally come into existence; but when the strife had subsided it became an object of criticism. In filling vacancies in its membership it was difficult always to ANNUAL ADDRESS OF THE PRESIDENT. XLI / select the best man, and sometimes abler men were left out of the academy than those who had the right kind of influence to be appointed. Scientific men are like other people, and they elect their friends and those whom they think will help them. Within a few years after the close-of the civil war the limitation of the num- ber of members was removed by act of Congress. The National Academy has now the power to determine the number of its members, and for the present this has been practically fixed at one hundred. Whether this number should be increased, and whether its member- ship should be more evenly distributed throughout the country are questions over which the academy has entire control. Its destiny, therefore, is in its own hands, and it is to be hoped, and it is to be ex- pected, that its career will be useful and honorable. To act such a part as this the academy must maintain a high and independent char- acter. Itshould choose for its members the best and ablest scientific men of the country, and it must never become the tool of the shrewd men who deal out the rich patronage of the Government. That there is need for such an independent body to criticise and assist in the direction of the scientific work done by public authority seems be- yond question. It is assumed, of course, that the General Govern- ment is to carry on scientific works of various kinds, a position which may be disputed by some, but which appears to be already practically conceded. How far the Government should enter on such works, and how much should be left to private enterprise, is a question of public policy.. But there are certain works which belong almost of necessity to the General Government. Thus the survey of our coast and harbors, a general geological survey, and a-good map of the country seem to belong to the work of the Government. These may be justified on the ground of their utility to the pub- lic. But there are other scientific works, not so directly con. nected with commercial and moneyed interests, that an enlightened government may properly undertake. Why should not there be in this country a first-class national astronomical observatory, where observations may be continued from one age to another with the best instruments of the times? Again, do not the elevated plains of the West offer an excellent opportunity for the determination of an arc of the meridian which may be extended from British America to the City of Mexico, and why cannot our General Government undertake such a determination? Must everything that is not strictly utilitarian be prohibited in the public works of our Repub- XLII PHILOSOPHICAL SOCIETY OF WASHINGTON. lic? JI do not think so. On the other hand the things that are purely commercial may generally be left to themselves. But if the Government is to doscientific work it should have the aid of men of science. We all know the tendency of public offi- cials to fall into habits of routine, and to spin out their work to an almost interminable length. There should be, therefore, a body of men who can criticise kindly, but boldly and justly, the labors of officials, and make them perform their duties as they ought. This, I think, should be one of the functions of the National Academy of Sciences. But to make this advice influential the Government must recognize the scientific men of the country, and give them some regular channel of communication through which their opin- ions can be made known to the public and to the executive author- ities. Thus far in the history of our Government the scientific man has generally been regarded as an expert who is to be carefully watched, lest he get the better of the officials who are set over him, and who sometimes undertake to manage affairs of which they have but little knowledge. The jealousy thus engendered is unfortunate. The man of science should be treated just as other men are treated, and there should be no grumbling at paying him a fair recompense for his labor. Our national military and naval academies are costly institutions, and fortunate is the young man who has a Congressman for an uncle or a cousin; but I have never heard a word from any scientific man against the cost of these establishments. So far as I know, their universal sentiment is, let us have the best of instruc- tion in military and naval science, for this is the cheapest. Our public buildings cost vast sums of money, but there is no objec- tion to such expenditures if the buildings are well and solidly constructed, since here, also, the best is the cheapest. On the other hand, is there not something very absurd in the manner the politician looks on the small expenditures for science, and the lavish ones that are voted for other purposes? Let us take a single case. A public vessel is “repaired,” to use an adopted euphemism, at one of our navy yards, and the cost of the repairs amounts to a million of dollars, or more than double the original cost of the ship. There is some astonishment at this, but we are told in a confident manner that the ship is greatly improved in strength and speed. The trial comes off, and while the ship is going along at her utmost speed, with the velocity of nine miles an hour, the engine breaks down. Here is a serious collapse, since before ANNUAL ADDRESS OF THE PRESIDENT. XLIII she was repaired the vessel could make eleven miles an hour. The head of the Department very properly orders an examination. Now, it might occur to superficial persons that those who repaired that ship had made mistakes. But the examining board weighs the evidence carefully, and it deliberately comes to the conclusion that the fault lies wholly with some unknown person who is more than three thousand miles away. The matter is mysterious, but the result is certain. The Government has been cheated, the money is gone, and the local politicians are happy. And the curious thing is that the public accepts the report of the examining board as en- tirely satisfactory. There is not a whisper of dissent from any news- paper in the land. And, after all, it is only half a million dollars, and do we not throw away ten times as much every year on rivers and harbors? Have we not seen a Senator boasting in his speeches that during the last twenty years more of the public money has been expended on the mountain streams of his own State than that State has paid taxes into the public treasury. Now change the case and let us suppose that some scientific man by bad management of his own or by failure of an assistant, has wasted ten thousand dollars of the public money. Ah, this is quite a different matter, and must be looked at from a different stand- point. How soon do we hear some smug official complacently re- mark that he always knew that scientific men cannot do business. And how eagerly the newspapers seize upon the case; how indig- nant the editors become, and how the head lines flctre. Is thee one law for the public functionary and another for the man of science ? But it is not right to leave this matter without further considera- tion. When we look at the advantageous position occupied by the officer of the army or navy we see immediately that this dod¢s not come from any personal merit he may have, but from the fact that he is recognized by law as an essential part of the Government. This position renders him in theory impersonal, and it is assumed that he has no private business of his own, but all his interests are one with those of the public. He has his member of the Cabinet to represent his views. His appropriations never fail, and he has no need to summon men from distant parts of the country to push his bills through Congress. Now, so long as the scientific man is. looked upon merely as an expert and an adventurer, and has no regular channel of communication with the Government he will XLIV PHILOSOPHICAL SOCIETY OF WASHINGTON. stand ata great disadvantage He may gain’a victory now and then, just as militia may sometimes beat regular troops, but the final result is pretty sure to be defeat. The position of the man of science must, therefore, be recognized by law if he is to be con- nected with public works in such a way that he may act freely and usefully. Such considerations will bring up the question of how far the Government is to proceed in the cultivation of science. If we examine the history of a country like England, where we have good records for a thousand years, we shall see that there has been a steady tendency toward three results. The first of these is personal liberty. The slave that was bought and sold has been changed to the serf, and the serf to the laborer. These changes have gone on with conflicts, and sometimes with retrograde move- ments, but on the whole they have proceeded until now, in nearly . all civilized countries, personal liberty is secured by law. The sec- ond result is the freedom of opinion. To control such an intangible thing as the opinions of men is a difficult matter, but it is a business which many men delight in, and the contest, though old, is yet a living one. When Sir Richard Saltonstall reproached his friends in Boston for persecuting Baptists and Quakers, on the ground that such persecutions made men hypocrites, the Puritan ministers at once replied that hypocrites are much better than profane persons like Baptists and Quakers.. But such people have been forced back from one position to another, explaining, apologizing, and retreat- ing, until now in several countries opinion is nearly free. There remain a few able men who pray for more superstition and bigotry, but they are the relics of a past time. The third result is the right of free exchange, and toward this end we have gained but little, since nearly all governments exercise their power in prohibiting among men'the free exchange of their products. The general course of events is thus to restrict the sphere of government, and to leave to” the individual more and more freedom of action. The chief duty of government is to see that justice is done between man and man, and to this end that the courts are fair and intelligent, and that our judges are not owned by rich men and corporations; that the public service is honest and efficient, and is not used for personal or polit- ical aggrandizement. But, granting all this, it seems to me that the Government may properly undertake such great scientific works as I have mentioned, with the condition that they be placed under proper control and inspection. To the successful accomplishment ANNUAL ADDRESS OF THE PRESIDENT. XLV of these works the man of science must be brought into the public service. He must be held responsible, just as other officials are, in his account of public money. Such a condition would subject him to some limitations that might be irksome at first, since it is pleas- ant for many to have at their disposal large sums of money which they may use at their pleasure, and almost every one fancies that he could do a great deal of good in this way. But such a method of handling public money is dangerous, and is apt to lead into trouble. Supposing that our public scientific works are to be carried on by men of science, what part the National Academy of Sciences shall act I cannot say, and it is not my province to urge on the Government the services of this academy, but here is a body of scientific men who have pledged themselves to the public service and they should be made to do their duty. And is there not ample room for intelligent criticism and suggestion in all the methods through which the public money is expended? Take the case of public schools, which is a kind of communism jusfified on the ground of utility to the State. What shall be the course of educa- tion in these schools? There is an unfortunate class of our fellow creatures that must be cared for at the public expense, but shall benevolent institutions encourage the production of such beings? Have we.not read of the English poorhouse where were found the grandfather, the father, and the son, all hearty men,—paupers breed- ing paupers? Do not some of our charitable institutions give plausibility to the saying that the mistakes of the good do more harm than the vices of the wicked? In fact, turn to any of the modes of public expenditure and examples will be found where sober, scientific judgrhent is necessary for the wise conduct of busi- ness. I come now to consider our own home society, the Philosophical Society of Washington. And, speaking cautiously and soberly, is it not to-day the best local scientific society in the country? This is owing partly and perhaps chiefly to our position at the Capital of a great people. Men from all sections come back to us as winter approaches, and many of them have interesting information to give. No other city of our country offers such advantages for fresh and early information of the investigations that are going on in the various departments of science. Our libraries in astronomy, math- ematics, ue medical science are among the best. As a general XLVI PHILOSOPHICAL SOCIETY OF WASHINGTON. library that of Congress must surpass all others in the country. These are advantages which make Washington an agreeable resi- dence for men of science and literature. I think also our society has a good plan of organization, thanks to the men who formed it. The general business can be safely con- fided to a committee, and in this way the meetings are made more interesting. This committee is so large that by a generous rotation in office most of the members may see and share, if they wish; the governing of the society. We have simple rules and they should always be enforced, since no society can afford to be overawed by any man, especially a society where we all meet as equals and where no favors are to be asked or granted. Our society has been estab- lished on a broad basis, to include all brances of learning, and as we have members from all the professions our meetings ought not to lack in variety of subjects. In such meetings the purpose of a paper should be to present the principal points clearly, and the author may generally trust to the intelligence of his audience to fill in the details. It is the failure to recognize this rule and the lack of arrangement that make some papers so long and tedious. Our society has its home in a beautiful city, and who’ that has seen its wonderful growth during recent years can doubt its future splendor and greatness? It is a city cosmopolitan in its character, Being the seat of political power, here will come the enterprising and adventurous from all parts of the country, with additions from other lands. Some of the brightest names in our scientific annals are those of foreigners who have made their homes with us. Letus welcome all earnest men, remembering that the principles of science are universal, and are not confined to any language or country. In respect of personal conduct we can have no better example than the noble man who was our first President, whose simple and devoted life was a model for every scientific man. If we need other inducements to devote ourselves to labors that may not give a great return of money, or lead to easy and luxurious lives, let us remem- ber that we live in a magnificent country, and one that has been dedicated as we hope to the liberty and welfare of the human race. Each one of us may do a little in adding to her scientific renown, which is now only beginning. Let us recall the words of the great Athenian: “I would have you day by day fix your.eyes upon the greatness of Athens, until you become filled with the love of her; and when you are impressed by the spectacle of her glory, reflect ANNUAL ADDRESS OF THE PRESIDENT. XLVIE that this empire has been acquired by men who knew their duty and had the courage to do it, who in the hour of conflict had the fear of dishonor always present to them, and who, if ever they failed in an enterprise, would not allow their virtues to be lost to their country, but freely gave their lives to her as the fairest offering which they could present at her feast. The sacrifice which they collectively made was individually repaid to them; for they received again each one for himself a praise which grows not old, and the noblest of all sepulchres—I speak not of that in which their remains are laid, but of that in which their glory survives, and is proclaimed always and on every fitting occasion both in word and deed. For the whole earth is the sepulchre of famous men; not only are they commemorated by columns and inscriptions in their own country, but in foreign lands there dwells also an unwritten memorial of them, graven not on stone but in the hearts of men.” BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON, GENERAL MEETING. BULLETIN OF THE GENERAL MEETING. 261st MEETING. | JANUARY 3, 1885. President Hatt in the Chair. The Chair announced the election to membership of Messrs. WiiuiAm Munpy PornpextTer and Asapu HALtt, Jr. The Auditing Committee, appointed at the annual meeting, sub- mitted the following report : Wasuineton, D. C., December 27, 1884. Mr. President and Gentlemen of the Philosophical Society of Washington : We, your committee, appointed at the annual meeting, December 20, 1884, to audit the report of the Treasurer for the year 1884, have the honor to submit the following report: We have examined the statement of receipts of dues from mem- bers, and of interest on bonds, and find the former to be $745, and the latter $95, as appears in the Treasurer’s statements of aceounts for the year 1884. In addition to the foregoing, $15 were repaid to the Treasurer by a member for extra printing, thus making the total receipts $855. We have examined the vouchers for disbursements for the same period, and find them correct. We have compared the return checks with the vouchers and with the entries in the bank book, and find them correct. We have examined the bank book, and found the balance as set forth to be correct, said balance, deducting the amount of two checks not yet returned, being $183.04, with Messrs. Riggs & Co. © vo 4 PHILOSOPHICAL SOCIETY OF WASHINGTON. The bonds referred to in the statement of assets were exhibited to us by the Treasurer, and consist of one $1,000 U.S. bond @ 44 per cent., one $1,000 U.S. bond @ 4 per cent., and one $500 U.S. bond also @ 4 per cent. All of which is respectfully submitted. H. C. Yarrow, Marcus BAKER, Witiram C. WINLOCK, ; Committee. On motion, the report was accepted and the committee discharged. Mr. J. S. Brnurinas made a communication on THE VITAL STATISTICS OF THE TENTH U. 8. CENSUS, presenting a brief outline of results soon to be published in Vol. XI of the Census Reports. Remarks were made by Messrs. Evtrorr, MALLERY, and AsAPH HALL. 262p MEETING. JANUARY 17, 1885. The President in the Chair. The Chair communicated an invitation to the members of the Society to attend the annual meeting of the Biological Society and listen to an address by Dr. C. A. WHITE. By request, Professor G. Srantey Hat, of the Johns Hopkins University, made a communication on RECENT EXPERIMENTS ON REACTION TIME, AND THE TIME SENSE, reviewing the methods of investigation and the results attained. An animated discussion followed by Messrs. Roprnson, HILGARD, Newcoms, Bruurnes, Eastman, PAuL, Wintock, AsapH HALL, and Professor GEORGE Davipson, of San Francisco. Mr. C. E. Durron then began a communication on PRACTICAL GEOLOGY versus SPECULATIVE PHYSICS, which was unfinished when the hour of adjournment arrived. GENERAL MEETING. 5 2638p MEETING. JANUARY 381, 1885. The President in the Chair. Fifty-eight members and guests present. The Chair communicated an invitation to the members of the Society to attend the ninetieth regular meeting of the Anthropo- logical Society, and listen to an address by Major J. W. PowE t. Mr. C. E. Dutton finished the communication begun by him at the last meeting on PRACTICAL GEOLOGY Versus SPECULATIVE PHYSICS, and the subject was further discussed by Messrs. Doorirrte, Mason, CLARKE, Warp, Watcott, Paut, Taytor, M. BaKkeEr, and Roprnson. 2640 MEETING. FEBRUARY, 14, 1885. The President in the Chair. Thirty-one members present. The Chair announced the election to membership of Messrs. CARL Barus, Frank Austin Goocn, and Wiii1Am HAuock. Messrs. F. W. Cuarke and J. 8. Ditier made a joint communi- cation on TOPAZ FROM STONEHAM, MAINE, describing the alteration of topaz into damourite. [The paper is published in the American Journal of Science, 3d series, Vol. XXIX, pp. 378-384.] Mr. Witu1Am H. DALL made a communication on TWO REMARKABLE FORMS OF MOLLUSKS. Mr. Datu described the anatomical features of the remarkable Chlamydoconcha Oreutti, of San Diego, California,* which is in fact a degraded lamellibranch, in which the shell has become internal and functionless, and is no longer adjusted by adductor muscles. He also described a remarkable feature which he had just dis- covered in Milneria minima, a small California bivalve, belonging *The main features of this notice appear in Science, No. 76, Vol. IV, p. 50, 1884. 6 PHILOSOPHICAL SOCIETY OF WASHINGTON. to the Carditide, and living on the backs of Haliotis shells. The female has the base of the shell pushed up into a deme in the median line, the opening to which is closed by an extension of the mantle. In the pocket so formed the young of the species are protected by the mother. The only other case among the lamellibranchs of such a protective modification is that of Thecalia concamerata, in which the same end is reached in a different manner. Both belong to the same family. The males of Milneria are without the pocket. Both _ sexes adhere by a byssus. Mr, W. B. Tayxor read a communication on GEOLOGICAL AND PHYSICAL THEORIES, in which, controverting the claims of practical or field geology—to the exclusion of physical theory—in the solution of physiographic problems, he contended that the family ties of planetary relationship cannot be disowned by geology. He thought the value of “ exter- nal” inductions fully shown by the probable effects of varying eccentricity in the earth’s orbit on secular changes of climate, as well as by a reference to the general inter-relation between the meeting boundaries of astronomical, geological, physical, and chem- ical science. On the physical side, he maintained that the sup- posed demonstrations of the earth’s comparatively recent consol- idation, (as well as of the limit assigned to the sun’s active life,) were entirely inconclusive: first, from the admitted uncertainty of the data, and secondly, from our ignorance that unknown factors might not enter into the problem. He therefore heartily agreed with Captain Dutton in recognizing the strong demands of geological induction for an incomparably longer chronology than terrestrial physics could as yet cipher out.* At the same time, the speaker contended that the certainty remained entirely unimpaired of an origin and a limit to solar—as well as to planetary—energy ; unless we were prepared to accept the absurdity of an infinite potential. He also pointed out that the doctrine of “uniformitarianism” does not require (as sometimes too readily supposed) an unvyarying degree of energy in geological dynamics throughout the distant past; but that the contrary was the more probable—if only from the broad generalization that all action whatever has its period or periods of maximum and minimum. » * Mr. Taylor’s paper was a reply to one by Mr. Dutton, of which the Society obtained no abstract. See pp. 4 and 5. GENERAL MEETING. 7 On the question whether geology itself gave us “traces of a begin- ning, or prospects of an end,” Mr. T. argued that stratigraphical geology unmistakably indicated its own genesis in the plutonic char- acter of its primeval “Archean,? or Laurentian—pointing to a time when the primitive surface was a molten ocean; and that when read in the light of palzontology such indication of a begin- ning was strengthened into convincing proof. by the receding grada- tions of animal and vegetable life, starting in the lower Silurian and its underlying Cambrian, with the humblest invertebrate forms of molluscan and crustacean life, and the simplest cryptogamous thallogens—the marine algze and fucaceze. And in this connection he referred to the memorable generalization of Louis Agassiz—that the geological successions of animal types correspond remarkably with the phases of embryonic development—as one of the most sug- gestive contributions ever made to the theory of evolution. The speaker then turned to the question of the earth’s interior fluidity; and after stating that the celebrated mathematical argu- ments of Hopkins from the “precession” value, and of Thomson from the hydrographic tides, had both been practically abandoned by the latter—though he still persisted in his pre-possessions for a solid globe (mainly on the specific-gravity skepticism), Mr. T. said he felt no difficulty whatever in accepting the geological evidences of a fluid earth enveloped by a flexile, friable egg-shell. With regard to the large amount of contraction and corrugation every where exhibited by this shell, he admitted that Mr. O. Fisher had conclu- sively disproved the sufficiency of Elie de Beaumont’s plausible hypothesis that the contraction is due to the secular cooling of the. planet. Mr. Fisher had however no better speculation to offer; and the answer to the riddle must come ultimately—not from petrol- ogy; nor from structural, or stratigraphical, or physiographical geology—but from cosmological physics. In conclusion, the speaker urged that the same inductions which so clearly establish the birth, the childhood, and the manhood of our planet, as inevitably impli- cate its decline, decadence, and decease; and he quoted passages from Byron’s familiar lines on “ Darkness,” as in the main a scien- tific prophecy. Mr. Paut spoke of the importance of a recent contribution to the subject of the earth’s rigidity by Mr. George H. Darwin. Mr. Gix- BERT thought that Darwin’s deduction of high rigidity was vitiated by his postulate of homogeneity. 8 PHILOSOPHICAL SOCIETY OF WASHINGTON. The President remarked on the great interest of the discussion opened by Captain Durron’s communication to a preceding meet- ing, and expressed his especial approval of the method in which Mr. Warp had approached the subject. 265TH MEETING. FrEeBRuARY 28, 1885. The President in the Chair. Fifty members and guests present. The Chair announced the election to membership of Messrs. Tuomas Corwin MENDENHALL, ALEXANDER ZiweEtT, Howarp Lincotn Hopextins, BAILEY WILLIs, JosEPH Paxson IppDINGs, and C. F. Marvin. Announcement was also made of the death of the Hon. Horace CAPRON. Mr. C. ABBE made a communication on METHODS OF VERIFYING WEATHER PREDICTIONS, giving a general account of the rules under which the U. S. Signal Office deduces from “indications ” and subsequent observations the published percentages of verifications. For purposes of prediction and verification the area of the United States is divided into a small number of districts. The “indication” for each district refers to the subsequent 24 hours, and is compared with the three next following weather-maps constructed from the observations, and the degree of correspondence for each station in the district is marked on a scale of five terms—0, 25, 50, 75, and 100. The published percentages are means of these marks. For certain special classes of phenomena— such as high-winds, frosts, and cold-waves—in which the indication only discriminates the occurrence and non-occurrence of a specific event, the formula for percentage of verification is v n +o in which n is the whole number of times the event is predicted, v is the number of verifications, or of events coincident with predictions, and o is the number of unpredicted events. It has been found for a large area in Europe, an area comparable GENERAL MEETING. 9 in size with one of the districts above mentioned, that, on the aver- age, a given type of weather—e. g., rain, threatening, fair, hot, cloudy, clear—can prevail simultaneously over only 85 per cent. of the area. If this law holds for the United States, we can hope for no better predictions while the existing system of districts is adhered to, for our percentage of verification is now approximately 85. Mr. Curtis described the method of verification adopted by the Deutsche Seewarte. It differs from that of the U. 8S. Signal Service in that the predictions are compared for verification with the observations at a single representative station in each district. Thus, for northwest Germany, the observations at Hamburg are employed. The limits for the prediction of stationary temperature are taken as + 1°C., on the basis of an investigation by Hann who found that the “change in 24 hours at Hamburg, in two-thirds of all cases, averages less than two degrees C.” Mr. Curtis showed that, for verifications to be directly comparable with respect to skill in prediction, the limits for “stationary” must vary in different dis- tricts and at different seasons of they ear. Unless such variations are adopted, the verifications should exhibit a uniform geographical difference, and an annual period, if the method employed possesses any scientific accuracy. As any such change of definition would be impracticable, it would seem desirable to base the range allowed for “stationary” temperature entirely on physiological considerations, leaving the question of comparability for subsequent discussion. _ In reply to a question by Mr. Paut, Mr. AxnbE said that the rules required that a prediction covering 24 hours should be verified by the maps compiled at the 8th and 16th hours, as well as by that compiled at the 24th. The desirablity of subdividing the geo- graphic sections to which the weather predictions apply was dis- cussed by Messrs. GILBERT, PAUL, and ABBE; and Mr. ABBE said that if any change was made, it would consist in the abandonment of specially defined districts and the substitution of individual States. Mr. H. A. Hazen remarked that if the prevailing weather in a district treated as a unit actually pertained, on an average, to but _ 85 per cent. of the district, then only omniscience could attain to a success in weather prediction measured by 85 per cent. of verifica- tion. 10 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. A. HAtui made a communication on VARIATIONS OF LATITUDE, discussing the observations tabulated by Mr. Fergola, and reaching the conclusion that the evidence fails to show that latitudes are variable. [The paper is published in the American Journal of Science, ig series, Vol. X XIX, pp. 223-27. ] Mr. R. S. Woopwarp said that he had recently undertaken the discussion of the subject with somewhat fuller data than those used by Mr. Haru. Postulating that the pole was changing its position by motion at a uniform rate on the arc of a great circle, he. com- puted the direction to be along the meridian 50° west of Green- wich, and the rate of motion about 2” per century. His inves- tigation was not yet completed, but he inclined to the opinion that actual change was indicated by the data used. Other remarks were made by Messrs. FARQUHAR, BAKER, and PAUL. 966TH MEETING. Marcu 14, 1885. The President in the Chair. Fifty-four members and guests present. The Chair announced the election to membership of Messrs. Rosert Porter HaAtrns and GreorGE MitrcHELL WRIGHT. The Chair read a letter from Mr. A. C. Peaz, announcing the death, on the 13th of March, of Mr. Trrran Ramsay PEALE, one of the founders of the Society. Mr. Peale accompanied Colonel Long in his explorations of the Rocky Mountains as naturalist, and was afterwards a member of the Wilkes’ exploring expedition. Mr. H. ALLEN HAZEN made a communication on THUNDERSTORMS OF 1884. ? This paper was a resumé of some of the investigations made by the Signal Office, looking to a detailed study of the origin, progress, . and development of thunderstorms. Over 13,000 special reports were received and studied. An attempt to connect thunderstorm frequency with the phases of the moon showed a rather marked GENERAL MEETING. 11 increase during the time of new moon, thus corroborating the result previously obtained by Dr. Képpen. A comparison of storm frequency with the period of solar rotation gave a marked maximum during the rotation. It was shown that taking the mean temperature over the whole storm region there was a close relation between the occurrence of high temperature and storm action, the former preceding the latter by about 24 hours. Taking the mean of the meteorological elements on 20 days of many storms at many of the stations, it was found that a marked low-pressure area was present to the northwest of the storm region, there was also a high temperature, while the humidity and weather were normal. On 20 days of few storms the reverse was found true, namely, a relatively high pressure and low temperature, the humid- ity and weather being normal as before. These results were highly interesting as bearing upon the conditions favorable to thunderstorm action. The detailed study gives promise of large additions to our knowledge of these meteors. In the ensuing discussing, Messrs. Mussry, Ray, ANTISELL, E. Farquuar, Pau, GILBERT, Roprnson, and Hazen spoke of the topographic, geographic, and seasonal distribution of thunderstorms and of the relation of the precipitation to the electric phenomena. Mr. ANTISELL said that moisture is essential to their generation; they are a secondary effect of the influence of the sun, not a pri- mary. Mr. KE. FarquHar spoke of the concentration of electricity by diminution of aqueous surface, when cloud-particles coalesce and form raindrops. Mr. 8. M. Burnert exhibited and explained THE JAVAL AND SCHIOTZ OPHTHALMOMETER. Mr. A. B. Jonnson began a communication on THE DIFFICULTY IN DETERMINING THE DIRECTION OF SOUND. 267TH MEETING. Marca 28, 1885. The President in the Chair. Forty-two members and guests present. The Chair announced the election to membership of Messrs. GusTAVE Louis Ravenk&, THomas MAREAN CHATARD, HERBERT 12 PHILOSOPHICAL SOCIETY OF WASHINGTON. MicHareLt WILson, WILLARD ADAMS SHUMWAY, and JEFFERSON FRANKLIN Moser. - Mr. A. B. Jonnson then completed his communication on THE DIFFICULTY IN DETERMINING THE DIRECTION OF SOUND, illustrating his remarks by a model of the topophone. The follow- ing is an abstract of the entire paper. Mr. Jounson said the hunter could not locate his game by the sound it made, unless the sound was frequently repeated; that the plainsmen could not locate each others’ site by shouts, until they were frequently repeated; that a child calling its mother in a house could not tell which room she was in, or even the floor she was on, until her voice was heard several times; that it was hard to tell, from its noise alone, whether a street-car was going to the right or left, in approaching it at right angles; in fact that it was not easy to fix by the ear alone, the location of the source of any sound. A dog aroused from sleep by the call of his unseen master fre- quently dashes in different directions before hitting the right one. Game startled by hearing a hunter’s tread will as readily run into, as out of danger. Blind people, despite the highly developed con- dition of their remaining senses, do not appear to be more able to determine the source of sound, other things being equal, than seeing people. It seems to be a question whether people generally do not use sight, touch or smell, involuntarily in locating sound. Hence, when they are so placed that they must depend on hearing alone, and err unusually in doing so, they consider such instances as ab- normal. After referring to subjective errors in audition, which frequently arise, Mr. Jounson spoke of the peculiar class of errors in audition into which mariners are apt to fall, often resulting in disaster. The collision between the ocean steamers Edam and Lepanto, was. referred to, in which the former was sunk, as the latter had erred an eighth of the compass circle in fixing her position by the sound of her fog signal, and thus ran into her. A lawsuit ensued, in which Judge Addison Brown, of the U. S. District Court of New York, decided against the plaintiff, holding “that an error of five points, in locating a vessel by the sound of her whistle in a fog, is not nec- essarily a fault, under the proved aberrations in the course of sound.” GENERAL MEETING. 13 Mr. Jounson then read from Judge Brown’s opinion, extracts from papers read before the Washington Philosophical Society by three of its former Presidents, Henry, Taylor, and Welling, and by himself, all as to the difficulty of determining the direction of sound, and he congratulated the Society that its conclusions had been adopted by the courts. As it was evident that the unaided ear could not be relied upon to fix the direction from which sound came, Mr. JOHNSON said atten- tion should be directed to giving the ear all possible assistance. That something of this kind could be done was proved, he thought, by Professor Morton’s experimentation with the topophone. This instrument had been devised by Professor Mayer of the Stevens Institute of Technology. It consisted of an arrangement by which two Helmholtz resonators were connected on the deck of a steamer with rubber tubes running into the cabin and with bars and rods which could be moved from the cabin. The actuating principle of the device was the neutralization of the dynamic force of the full sound wave by the half sound wave, thus approximating silence, and thus indicating automatically, within ten degrees, or less than one point of the compass, the direction of the sound. Mr. Pau. remarked that the bar connecting the resonators should be shorter than the wave length of the sound under observation, since otherwise deceptive results would be obtained with the two resonators in similar phases of different waves. Mr. TayLor ques- tioned the utility of the instrument, though heartily applauding its ingenuity. The real difficulty in determining sound direction arises from the heterogeneity of the air in point of density and moisture, and especially from its indeterminate differences of movement, whereby diffractions and refractions are occasioned many times greater than those affecting light. The topophone, like the ear, is cognizant only of the final direction of the incident beam of sound, so to speak, and can tell us nothing of the direction of the source of sound. Mr. E. FarquHar remarked that the verdict of the ear in regard to direction is usually just; the conditions under which it errs are exceptional. He thought there was a rapid adjustment by motion of the head, from which the general direction is almost in- voluntarily ascertained. Mr. F. Baker said that animals, such as, for example, the carnivora, make fewer mistakes than man, and this is probably due to their muscular control of the external ear. When the ears are Becee up in listening, special tensions may be given 14 PHILOSOPHICAL SOCIETY OF WASHINGTON. to the concha. When man listens intently he adjusts the tensions of the membrana tympani. “ The possible influence of wind velocity on the pitch of sound was discussed by Messrs. PAut, Tayntor, and GILBERT, and other remarks were made by Messrs. Kine, Haui, Evuiorr, and H. Farquiar. Mr. WaAsuinaton Marruews began a communication on MYTHOLOGICAL DRY PAINTINGS OF THE NAVAJOS, which occupied the remainder of the evening. Its completion was deferred. 268rH MEETING. AprRIL 11, 1885. Vice-President Briur1nes in the Chair. Forty-six members and guests present. Mr. Wasuincton Matruews concluded his paper on MYTHOLOGICAL DRY PAINTING OF THE NAVAJOS. This paper described an art in use among the medicine men of the Navajo Nation, by which they represent various mythological conceptions on the sanded floor of the medicine lodge with dry pig- ments of five different colors. These dry paintings are from ten to twelve feet in diameter, and are quite intricate, containing from five to thirteen mythological figures of large size. About a dozen men labor from eight to ten hours in making them. When completed, they are after some ceremonies completely obliterated, and even the sand on which they are drawn is carried out.of the lodge and thrown away. The existence of such an art is not generally known and the figures are not copied from any visible standard but are retained in the memories of the medicine men. The paper was illustrated with seven water-color paintings— reproductions of the Navajo drawings. Four were pictures of the esoteric portion of a Navajo ceremony called dsilyidje-qacal or “song in the mountains,” and represented visions or revelations of the Indian prophet who instituted these ceremonies. The remaining three pictures were from a ceremony known as kledje-qagal or “song of the night,’ and represented the revelations of another Navajo GENERAL MEETING. 15 prophet, he who, according to their mythology, instituted the latter ceremonies. The symbolism of the pictures was explained, and such portions of the myths as directly referred to the pictures were related. The first picture showed the house of the great snakes. The second represented the gods of the domestic plants, with the prin- cipal domestic plants of the Indians, corn, bean, pumpkin, and to- bacco, indicated by highly conventionalized figures. The third pic- ture was of certain goddesses of great height, called the Bitsihi-nez or Long-bodies, which the prophet is said to have seen in a house made of dewdrops. The fourth drawing depicted the sacred arrows used in the dance, which the medicine men pretend to swallow. The lecturer explained the trick by which this imposture was car- ried out. The fifth picture represented the peculiar myth of the tsis-naole or whirling sticks. It represents two logs placed in the center of a lake so as to form across. Eight divine beings sat on these logs, which were kept constantly whirling by other gods who poked the logs with plumed staves. There were twelve apotheosized human figures in the picture. The sixth picture showed the kledje qacal as it took place in the abodes of the gods when the Navajo*prophet first saw it, and is a fair representation of the dance as it is per- formed among the Navajos to-day. The seventh painting repre- sented a portion of the dance among the gods, at a time when a spell had been cast upon them by the angry Coyote-god. The figures in the east of the pictures are painted in white, those in the south blue, those in the west yellow, those in the north black. This is the usual order of Navajo color symbolism; but sometimes the white is assigned to the north and the black to the east; instances were given where this interchange took place. The gods in many cases are shown standing on rafts made of sun- beams, such rafts being favorite vessels of the gods when they make their aerial journeys. The gods are depicted with round heads, the goddesses with quadrangular heads. In the dances, the actors wear masks of corresponding shapes to indicate males and females. Seven of the pictures were surrounded with symbols of the rain- bow deity, which with the Navajos, as with the Greeks, is a goddess. The sanded floor on which the pictures are drawn is slightly sprinkled with charcoal; this is to convey the idea of a surface of clouds, for it is said that in the houses of the gods these pictures were drawn on sheets of clouds. 16 PHILOSOPHICAL SOCIETY OF WASHINGTON. The speaker closed by referring to the transitory nature of the pictures, and showing how it might easily have happened that no knowledge of them would ever transpire. Mr. Gitpert THompson described pictures on the walls of a shallow cave near San Antonio Spring, New Mexico, and exhibited copies of the same. The outlines of the pictures are etched on the rock, and several different colors are employed, both in the etched grooves and on the plane surface of the rock. Mr. MarrHEws explained the relations of these drawings to Navajo myths and cere- monies. In response to questions by Messrs. Bituines, M. Baxer, Pavt, and Mauuery, Mr. Marruews said that individual drawings are not repeated on the same occasion. The ceremonial dances, most of which take place only during the season when the snakes hiber- nate, are executed for the benefit of invalids, or for the gratification of individuals who by conventional fiction are regarded as ill. They are paid for, and they are very expensive luxuries, the gross bill of expenses sometimes amounting to the value of $300. The patient or his friends select the particular dance to be performed. After the completion of the picture, the patient enters the lodge, and is seated upon the east figure, while a litany is chanted. Sand from one of the painted figures is then applied to his body, sand from the arm being applied to his arm, &e. Mr. Pavt described a similar art of dry-painting, practiced by the Japanese, but for amusement only. Bold designs of great variety are executed skillfully and rapidly in-public places, for which the artist receives compensation from the by-standers. Wealthy Japan- ese also employ persons to dance for them, and, for that matter, to fish for them; but the motive appears to be pleasure, and not religion, or health. Other remarks were made by Mr. JENKINS. Mr. W. C. WINLOcK made a communication on COMETS II AND III, 1884, i!lustrating his subject by models exhibiting each cometary orbit in its proper relation to the earth’s orbit, and also by plane diagrams and sketches of the comets. GENERAL MEETING. i7 Mr. RAvENE spoke of the perturbations of Barnard’s comet occasioned by the attraction of Jupiter, and thought it might have been brought into the solar system by that attraction. Other remarks were made by Mr. PAvt. Mr. H. M. Paut commenced a communication on PROBLEMS CONNECTED WITH THE PHYSICS OF THE EARTH’S CRUST. Its completion and discussion were deferred to a future meeting. 269TH MEETING. APRIL 25, 1885. The President in the Chair. Fifty-three members and guests present. Announcement was made of the election to membership of Mr. CHARLES FREDERIC ADAMS. Mr. Frank BAKER made a communication on MODERN IDEAS OF BRAIN MECHANISM. Remarks were made by Messrs. E. Farquuar, H. FARQUHAR, M. Baker, and DoouirtrLe. Mr. L. F. Warp began a communication on THE FLORA OF THE LARAMIE GROUP, the completion of which was deferred for lack of time. 270TH MEETING. May 9, 1885. The President in the Chair. Forty-four members and guests present. Announcement was made of the election to membership of Mr. Water Harvey WEED. Mr. Lester F. Warp completed the reading of his communica- tion on THE FLORA OF THE LARAMIE GROUP. [It will appear in the Sixth Annual Report of the U.S. Geological 2 18 PHILOSOPHICAL SOCIETY OF WASHINGTON. Survey, as a portion of the author’s “Synopsis of the Flora of the Laramie Group.’’] R Remarks followed by Messrs. GitBERT, ELLIoTT, and WHITE. Mr. T. C. MENDENHALL made a communication on THE MEASUREMENT OF TEMPERATURE AT DISTANT POINTS. Remarks were made by Mr. Ev.iorr. Mr. GusTaVE RAVENE gave an abstract of a communication pre- pared on THE ASTEROIDS. Remarks were made by Messrs. TayLtor, H. Farquyar, and ELLIort. 271st MEETING. May 23, 1885 The President in the Chair. Forty-one members and guests present. The Chair announced that only one more meeting would be held before the summer vacation. Mr. A. GRAHAM BELL made a communication on THE MECHANISM OF “CLICKS” AND “CLUCKS.” Remarks were made by Messrs. M. BAKER, GILBERT, and Ros- INSON. Mr. H. M. Paut completed his communication on THE CONDITION OF THE EARTH’S INTERIOR. Mr. W. B. Taytor made a communication on THE CRUMPLING OF THE EARTH’S CRUST, in which, referring to the plausible hypothesis of contraction by cool- ing—which had been so largely accepted, he contended that the amount of cooling and contraction since the formation of a consis- tent crust had been much less than even the opponents of that hypothesis had conceded; while the maximum amounts estimated by its adherents would still be wholly inadequate to represent the GENERAL MEETING. 19 actual measure of compression indicated by the average degrees of plication of the stratified rocks. Supposing these to represent a a reduction from the original circumference of the crust of one-eley- enth, this would involve a former excess of volume of about one- third. The speaker then gave an historical sketch of the growing con- viction among physicists that from the tidal retardation of the earth’s rotation, the length of the day must have been much shorter in remote geological eras than at present—and consequently the ob- lateness of the terrestrial ellipsoid considerably greater. Estimating that a day of six hours would give an equatorial enlargement of about one-tenth (without taking any account of volumetric change by reduc- tion of temperature), he thought this morphologic change an adequate explanation of the.observed crumpling of the earth’s crust; and claimed that the cause assigned is both a true and a sufficient one. This larger oblateness would imply an equatorial bulge 396 miles greater in radius than the present ; and a corresponding depression of the poles 658 miles below their present levels. As in a general way confirmatory of this hypothesis, Guyot’s statement was quoted that “On the whole, the reliefs begin with the vast, low plains around the polar circle, and go on increasing from the shores of the Arctic ocean toward the tropical regions;” and that “the ocean basins become less deep toward the - = A pci as the lands become lower toward the same region.” [This paper is printed in full in the American Journal of Science, 3d Series, Vol. XXX, pp. 249-266.] 272ND MEETING. JUNE 6, 1885, The President in the Chair. Twenty-eight members present. Mr. J. P. Ipprnes made a communication on THE COLUMNAR STRUCTURE IN THE DIABASE OF ORANGE MOUNTAIN, N. J. [ Abstract. ] The paper describes the occurrence and structure of the “ trap” rock in the neighborhood of Orange, with special reference to the arrangement of the columns in John O’Rourke’s quarry and in the 20 PHILOSOPHICAL SOCIETY OF WASHINGTON. Undercliff quarry in Llewellyn Park. The chief interest centers in the groups of radiating columns which form the, upper portion of the exposures, the lower portion being divided into vertical columns or blocks of larger size. That these two portions of the lava sheet belong to one and the same mass is shown, not only by the contin- uity of the rock of the upper and lower parts, but also by the mutual accommodation of the different sets of columns, which taper off and curve in one direction along lines of oblique junction ; and by the fact that the positions of the columns are not what they should be along the supposed lines of contact. The columnar structure in volcanic lavas is unquestionably a cracking produced by shrinkage upon further cooling, after the mass has consolidated into rock. Considering the origin and progress of a crack produced by the shrinkage of a homogeneous mass, we see that, starting with a plane surface over which forces producing contraction are acting uni- formly, the contraction produced on the surface of the mass in a given time will be greater than that produced at some depth within the mass, and that it will decrease gradually from the surface in- ward. As the contraction progresses, the limit of tension in the direction of the surface will be reached before that in the direction of depth, causing a rapture across the direction of the surface, and as the limit of tension for the layer next to the surface is reached it will rupture in the same direction as the surface layer did, and soon. The direction of the crack is at right angles to that of greatest contraction, or normal to the line of maximum strain. Moreover the condition of the mass at the moment the limit of tension along the surface is reached may be graphically repre- sented as in figure 1, the contraction being a maximum in the -----,---- Fig.1. top layer and diminishing successively in each layer beneath to that with the initial expansion. The distance of this layer from the surface being taken as unity, the maximum contraction at the GENERAL MEETING. vcd | moment of rupture will be equal to twice the tangent of a. In other words 2 tan «@ represents the limit of tension, and will be con- stant for any given substance. As the conductivity of a cooling body is not directly proportional to the degree of radiation from its surface, the difference between the contraction of successive layers of a rapidly cooling mass will be greater than between those of one cooling less rapidly, and what may be styled the angle of contraction will be greater in the former case than in the latter. And if we assume a certain rate of cooling to have caused a single rupture in a given extent of mass (repre- sented in fig. 1), then a greater rate of cooling, which would pro- duce in the same extent of mass a contraction represented by a n 6 ?tan a If the forces producing contraction are unequally distributed over the surface a 6, figure 2, being a maximum at ¢, the maximum greater angle, ?, will cause as many ruptures as the ratio Fig. é. strain at the beginning will be in the direction of the surface, and the cracks will start normal to it; but their progress inward will no longer be uniform. At the end of a given time the limit of ten- sion reached by a greater force, at f, will be farther from the sur- face than that reached by a less force, at g, and the line of maxi- mum strain in this portion of the mass will be 9’ f’, to which the crack of parting will be normal. At the end of another given time the direction of the crack will be again changed, and the same action taking place in the other parts of the mass will result in a system of diverging cracks. So far we have considered the shrinkage in one direction in one plane only, that is, parallel to the cooling surface in a plane at right angles to it. But a homogeneous mass contracts equally in all pa PHILOSOPHICAL SOCIETY OF WASHINGTON. directions, and the contractile force which produces cracks at certain distances in a given mass will exert itself equally in all directions over a surface uniformly subjected to the cooling forces, and will, at the instant of fracture, act towards centres, whose dis- tance apart is dependent on the rate of cooling. If the mass is per- fectly homogeneous the centres of contraction will be disposed over the surface with the greatest uniformity possible, that is, they will be equidistant throughout, and the resultant fractures will be in a system of hexagons. If from any irregularity in the composition or petrographic structure of the rock the contractile force acts un- equally in different directions, the form of the polygons will be less regular. The mutual influence of the forces producing different columns as they approach each other is readily understood from the foregoing. Take the case of two columns, S, S’, approaching one another (Fig, 3,) and suppose the progress of the maximum strain to have reached a b, a’ b’, the forces producing contraction acting through a and a will meet and react on each other before those acting through } and 0’, so that the points of maximum strain at any given time will have advanced farther along the lines through a and a’ than through band b’. The lines of greatest strain will then beed and ¢’ d’, and the cracks normal to them will take the directions ¢ e and ¢ é, This will continue.-till they become parallel. If there were but two columns forming at equal rates they would curve symmetrically and continue in parallel directions‘and of con- stant width, but if one column progresses more rapidly than the GENERAL MEETING. 23 other they will no longer curve to the same extent, and the slower one will curve more than the faster one. Now, instead of two single columns, there,are always two groups _ approaching one another, and these prevent the continuation of the columns beyond the bend, pinching them out and causing them to taper off as already observed in the quarry described. The difference in the systems of cracks of the lower and upper portion of this lava sheet may then be accounted for by a difference in the rate of cooling from the lower and upper surfaces, the more frequent fractures arising from the more rapid cooling, and the two systems proceeding from their initial planes until they blend in one another within the mass. If for any reason the cooling from one surface should take place irregularly and from any point proceed more rapidly than from others, it is evident that there would result a set of columns diverg- ing from this point as a focus. Besides the columnar fracturing, a division of the mass by trans- verse cracks, especially near the top of the lava sheet, is more or less noticeable. There remains to be considered the contraction exerted in all other directions through the mass. Since the uniform contraction of a homogeneous body acts equally in every direction through it, its effect corresponds to the equal shortening of the radii of a sphere of such a body. If through any resistance cracking or parting occurs it will take the form of concentric spherical shells. If for any reason the resistance to the contracting force in a par- ticular direction be counteracted by some other force acting in the same direction the parting will no longer be spherical, but ellipsoidal, as will be seen from Figure 4, where abc represents a section through the sphere along the radii of which contraction takes place. A uniform resistance in the direction of the radii represented by 24 PHILOSOPHICAL SOCIETY OF WASHINGTON. ec, dd’, ete., will produce a parting parallel to the arc of the circle cd’ é,etc. If, however, the resistance in a direction parallel to ae be neutralized by some force, the resistance along the different radii will be diminished by the amount of the vertical component in each case, and the resulting fracture will be parallel to the ellipse ¢ 0’. The relative tendency to fracture also is represented by the area bcd’. Such a parting is actually present in the large columns in John O’Rourke’s quarry, the major axis of the ellipsoid being vertical, as it should he if the weight of the superincumbent mass counteracted any resistance to contraction in a vertical direction. The wavy form of the columns, large and small, suggests irregu- larities in the mass which disturbed the uniform advance of the lines of maximum strain and caused them to deviate from parallelism. The superficial banding of the large vertical columns by nearly horizontal notches or grooves, resembling layers of bricks or rude chiseling, appears to be simply a modification of the plane of the crack. The paper closes with a description of the microscopical charae- ter of the Orange rock, which from its identity with many recent basalt flows leads the writer to the conclusion that it should be classed as a coarse-grained basalt or dolerite, as Prof. E. S. Dna has called the similar rocks in the Connecticut valley. The occurrence of the rock in question as a surface flow is ren- dered highly probable by its glassy nature, and the disposition of the columns, which resembles that of many lava sheets in western America, as well as of those in central France. G. Poulett Scrope, in his work on “ Volcanos” (2d edition, London, 1872), discusses the question of the origin and nature of columnar structure in lavas and other substances, and by a somewhat different course of reasoning arrives at essentially the same conclusions as those reached in the present paper. Mr. W. J. McGeEsr then made a communication on THE TERRACES OF THE POTOMAC VALLEY. Remarks were made by Messrs. Warp, Toner, Ropinson and Bates. ~ GENERAL MEETING. 25 273D MEETING OcTOBER 10, 1885. The President in the Chair. Thirty-nine members and guests present. Announcement was made of the death since the last meeting of two members of the Society, FRANKLIN BEenyJAMIN HovucH and WaAsHINGTON CaRUTHERS Kerr. Messrs. J. S. Brnyines and WasHINGTON MArTTHEws made a joint communication on ANTHROPOMETRIC AND REACTION-TIME APPARATUS. They exhibited a set of the anthropometric apparatus, devised chiefly by Mr. Francis Galton, and recently employed in the anthro- pometric laboratory of the London Health Exhibition. The appara- tus test acuteness of hearing, strength of vision, color discrimination, the estimation of the aliquot parts of a line, the estimation of a right angle, the rapidity of arm movement in striking a blow, the strength of certain muscles, the weight, the height (sitting and standing), span of arms, and chest capacity. Their peculiar characteristic is their simplicity, which permits of their use by the person measured, with a minimum of instruction and supervision. There was also exhibited a device by Mr. James McKeen Cattell, for the determina- tion of the time occupied by various sensations, mental processes and muscular actions. There followed an informal discussion by Messrs. H. A. Hazen, KE. Farquyar, Haru, H. Farquaar, Harkness, Mussrey, Woop- WARD and MAson. 274TH MEETING. OcToBER 24, 1885. The President in the Chair. Fifty-three members and guests present. Mr. H. ALLEN HAZEN made a communication on THE CONDENSING HYGROMETER AND SLING PSYCHROMETER. [Abstract. ] By way of introduction the results of a few experiments were given, tending to show the best interval that can be obtained in the ; 26 PHILOSOPHICAL SOCIETY OF WASHINGTON. graduation of degrees upon a thermometer scale. These were made with a common vernier of a mercurial barometer. A mark on the vernier was placed at each tenth (by estimation) of intervals of .05”, 10”, .15”, .20”, .30”, and .40”, marked on the limb, and the vernier read for each estimation. Over 1300 readings were made, and these showed little difference in the splitting to tenths for the last 5 inter- vals above, but .05” seemed too small for accurate work. Results and methods of observing the Alluard form of Regnault’s condensing hygrometer were given. It was shown that if the ther- mometer immersed in the liquid is placed quite near the plate where dew is to appear, there is little or no danger of the air as it passess into the liquid harmfully affecting the thermometer. The com- plaint of some that the dew is deposited in the air, having a tem- perature frequently 40 or 50 degrees above the liquid, and hence that the thermometer can hardly give a correct dew-point tempera- ture was shown to have little weight, since the results, with a slight difference between the air and dew-point, at which time the effect would be small, are nearly identical with those where the difference is large, and the effect would be large. It was shown that the great difficulty in nearly all psychrometric work up to the present time has been the disregard of a sufficient ventilation of the wet-bulb thermometer. The sling psychrometer, with a few precautions in its use, furnishes results entirely satisfactory. The comparisons so far made between the two instruments have shown a remarkable uniformity under all conditions of moisture and temperature, and have left little to be determined in order to make either apparatus one of precision. A probable effect of compression of ice on the wet bulb at temperatures of 0° F., and below, was shown to exist, though this may be due to the lack of conduction on the part of the ice for the residuum of heat in the bulb. The question of the effect of height above sea on the indications of the above instruments was touched upon, and it was shown that the effect was small and only to be detected by the most refined obser- vations. Also, that until we have some law for reducing humidity results to sea level, the propriety of introducing such effect into tables is questionable. Mr. T. C. MenpENHALL exhibited a new volt-meter devised by Sir William Thompson. The principal difficulty entountered by earlier instruments of this class has arisen from the inconstancy of the magnetic force of the terrestrial field. By this instrument ter- GENERAL MEETING. DY restrial magnetism is eliminated. The force produced by the current is opposed by a weight and is thus measured in terms of gravity. Mr. MENDENHALL also renewed the discussion of the preceding evening on reaction time, reciting the methods and results of his own experiments in 1871. Remarks on the volt-meter were made by Mr. Ev.tiort, on re- action time by Messrs. Pau, Mason, and MatTHews. Mr. Wiii1Am HarxkNness made a communication on FLEXURES OF TRANSIT INSTRUMENTS, pointing out that the flexures induced by the weight of a transit, in positions other than vertical, are not eliminated by reversing the instrument, and developing equations for the discussion of the errors so far as they can be determined by the aid of collimators. \ 275TH MEETING. NovEMBER 7, 1885. The President in the Chair. Sixty-nine members present. Mr. F. W. Ciarke made a communication on AN ATTEMPT AT A THEORY OF ODOR, in which he accounted for the lack of knowledge as to the con- ditions of action of this sense by the difficulty of dissociating it from taste; and, while disclaiming any thought of attempting a physio- logical explanation of the sense, proposed the following as the essen- tial objective conditions : 1. To be odorous, a substance must be volatile, so that it may come into contact with the mucous tissue of the nose, and 2. It must be chemically unstable, so that it may undergo chemi- cal changes in contact with that tissue. Mr. Clarke gave some confirmatory instances, from the compounds of hydrogen with sulphur, selenium, and tellurium, and from the C, H,, O, group of acids (formic, acetic, etc.) Mr. ANTISELL called attention to the connection between a low boiling-point and simplicity of chemical constitution, and to the associated fact that organic substances containing a large number 28 PHILOSOPHICAL SOCIETY OF WASHINGTON. of equivalents of carbon are inodorous. He ascribed the smell of prussic acid to arriére-gout rather than true odor. * Mr. Brxurncs showed that from the peculiarly exposed condition of the olfactory nerve-terminal, it was subject to irritations that must be distinguished from odors properly speaking. Mr. CLARKE then made a communication on “THE FLOOD ROCK EXPLOSION, in which he described the arrangements for observing earth tremor at stations near New York city, and particularly that at Ward’s Island, occupied by Mr. Mendenhall and himself. The tremor was felt at that station a full second before any disturbance was seen in the surface of the water above Flood Rock. Mr. C. F. Marvin, in a communication on the same subject, de- scribed the form of seismoscope used, in which a small agitation closed an electric circuit, and sounded an alarm. Mr. Paut followed with a communication on the same subject. Mr. CLARKE quoted some results of observations made at Gen, Abbot’s stations, giving a mean velocity for the tremor from Flood Rock to Pearsall’s of 2.6, and to Patchogue of 2% miles per second, and thus indicating a retarded rate of transmission. Mr. Rosrnson suggested that the blasts at the new water-works reservoir would afford a good opportunity for measuring the velocity of earth tremors. Mr. H. Farquyar spoke of the sounds coincident with the flight of meteors reported by some observers, as indicating the need of caution in accepting observations of sound in this connection. Mr. Rogrnson had distinctly heard two sounds after blasts at the water-works; one immediately following the tremor, through the earth, and a later one through the air. Mr. CHATARD had made a similar observation in connection with mining blasts. Mr. :Durron said that his impression, from eruptions of Hawaiian volcanoes, had been otherwise, and that the general testimony with regard to earthquakes is that the sound precedes the shock. GENERAL MEETING. 29 276TH MEETING. NovEMBER 21, 1885. The President in the Chair. Fifty-seven members present. Announcement was made of the election to membership of Mr. Tuomas Hampson. The Chair communicated to the members an invitation from the Chemical Society to attend its meeting on December 10th and listen to the address of its retiring president, Prof. F. W. CLARKE. Mr. G. Brown GoopeE and Mr. C. V. Ritey made communica- tions on THE SYSTEMATIC CARE OF PAMPHLETS, exhibiting the appliances employed by them and illustrating their _ methods. . Mr. Goope furnishes each pamphlet with a firm, durable cover, by which it is protected from injury, and at the same time kept separate for convenient use and classification. Photographs, draw- ings, newspaper clippings, etc., are preserved in the same manner. [A full description of his appliances may be found: in Science, vol. VI, p. 337.] Mr. Rinry employs inexpensive, flexible covers, occupying less space, and stores them in the “ institute pamphlet case.” Mr. B. Pickmann Many, being invited to participate in the dis- cussion, exhibited his method of binding pamphlets together, a method in which four holes are punched at standard intervals in each pam- ’ phlet and corresponding holes, in flexible hinges to stiff covers, so that a convenient volume can be made up by merely inserting and tying two cords, and any desired rearrangement or insertions can be made, the holes for binding always corresponding. [See Science, vol. VI, p. 407, and Library Journal, vol. VIII, p. 6.] Mr. Bruurnes described the tin boxes used in the storage of the immense file of pamphlets in the library of the Army Medical Museum. Mr. Warp and Mr. Toner spoke in approval of the substantial covers adopted by Mr. Goode. Messrs. GILBERT, TONER and Harxness opposed the binding of several pamphlets together, believing that such combination interferes with their use and ready classification and reclassification. Other remarks were made by Messrs. DALL, Mussry, and Doo- LITTLE. 32 30 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. J. S. Bruiines made a communication on GERM CULTURES, exhibiting specimens of cultures of chromogenetic and pathogenetic micro-organisms, to illustrate the improvements in methods of investigating these organisms which have been made of late years. Attention was called to the value of culture upon semi-solid media such as peptonized gelatin, agar agar, coagulated blood serum, etc., as a means of differentiating micro-organisms, and of obtaining pure cultures to be used for experimental purposes; and the applications of the method to testing the efficacy of disinfectants, to water examinations, &c., were pointed out. 277TH MEETING. DrEcEMBER 5, 1885. By courtesy of the officers of the Columbian University, the meeting was held in the law lecture room of the University build- ing. Members of the Anthropological, Biological, and Chemical Societies and their friends were present by invitation. Vice-President BiLLines occupied the Chair. Present, one hundred and sixty members and guests. The President, Mr. AsApH HALL, read his annual address, taking for his subject : AMERICAN SCIENTIFIC SOCIETIES. [Printed in full on pp. XxxIII-XLVII.] A resolution of thanks was moved and unanimously passed. 278TH MEETING. DECEMBER 19, 1885. THE FIFTEENTH ANNUAL MEETING. The President in the chair. Thirty-eight members present. The minutes of the 260th, 276th, and 277th meetings were read and approved. GENERAL MEETING. 31 The Chair announced the election to membership of Mr. Jacos Lawson WorTMAN. The report of the Secretaries was read and accepted. The report of the Treasurer was read, received, and referred to an auditing committee, consisting of Messrs. J. M. Toner, O. T. Mason, and T. C. Mendenhall. On motion of Mr. Harkness, the thanks of the Society were tendered to the Treasurer and Secretaries for the efficient perform- ance of the duties of their offices. Officers were then elected for the year 1886. (The list is printed on page XV.) The rough minutes of the meeting were read, and the Society adjourned. \ ia pike os t one or ial ok xn Mie 4 a pabhe , Meakin Oe bs Bani ON Gp iirairiig anh 9 i: f : Pero ir ee Yard de eased a a Here ee IR) OEY has aa \ i i ‘ { Abie diy Sobel agit?) cera es ’ f Poe Miser: Stl j ! ‘ ane gui bi ry ‘4 A a i - AGhVT Ry Peet ith 7 vn \ ‘i o j dat rae Th EY j , we v4 iW fe a cal} viel wide nah} 0e eae ee , an ®, Cie Ae . . A. foley Re ee aa ee : ( 3 f it 1 aye i ima? ALY Lie Wet ee ah, (fh 4} ete ; Ms { j y« a ; ; ; . . ‘ ; Ba ea i el holy ai ae eel bY Qo SS ae j - \ \ i A ‘ P ‘ 2 x \ t 4! Un ‘ \ i ‘ { ‘ ‘ ‘ i a“ ‘ ‘ 4 BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. MATHEMATICAL SECTION. 33 STANDING RULES OF THE MATHEMATICAL SECTION. 1. The object of this Section is the consideration and discussion of papers relating to pure or applied mathematics. 2. The special officers of the section shall be a Chairman and a Secretary, who shall be elected at the first meeting of the Section in each year, and discharge the duties usually attaching to those offices. 3. To bring a paper regularly before the Section it must be sub- mitted to the Standing Committee on Communications for the stated meetings of the Society, with the statement that it is for the Mathematical Section. 4. Meetings shall be called by the Standing Committee on Com- munications whenever the extent or importance of the papers sub- mitted and approved appear to justify it. 5. All members of the Philosophical Society who wish to do so may take part in the meetings of this Section. 6. To every member who shall have notified the Secretary of the General Committee of his desire to receive them announcements of the meetings of the Section shall be sent by mail. 7. The Section shall have power to adopt such rules of procedure as it may find expedient. i ) OFFICERS OF THE MATHEMATICAL SECTION FOR 1885. Chairman, G. W. H1tt. Secretary, Marcus BAKER. LIST OF MEMBERS WHO RECEIVE ANNOUNCEMENT OF THE ABBE, C. AvERY, R. S. Baker, M. Batss, H. H. Biiuines, J. 8. Burasss, E. 8. CurRisTIE, A. S. CoFFin, J. H. C. Curtis, G. E. DELAnD, T. L. Doouitrie, M. H. EASTMAN, J. R. E1mMBEck, W. Exuiott, E. B. Farquuar, H. Fuint, A. S. GILBERT, G. K. Gorgz, J. H. GREEN, B. R. Hatt, A. MEETINGS. Woopwarp, R. S. HALL, Aer HARKNEss, W. Hazen, H. A. Hrncarp, J. E. Hit, G. W. Hovexins, H. L. Kine, A. F. A. KuMMELL, C. H. Lzeravoour, E. B. McGez, W. J. NeEwcoms, §. PaAvL, H. M. Ravens, G. L. RitTER, W. F. M’K. Rogrnson, T. Smitzry, C. W. Stone, O. Tartor, W. B. Urton, W. W. WINLocKyW. C. 36 BULLETIN OF THE MATHEMATICAL SECTION. 16TH Meretine. JANUARY 7, 1885. The Chairman, Prof. AsApH HALL, presided. Nineteen members and guests present. Election of officers of the Section for the year 1885 was then held and resulted in the selection of Mr. G. W. Hrvx as Chairman and Mr. Marcus BAKer as Secretary. Mr. E. B. Exxiorr then presented a communication entitled EXAMPLE ILLUSTRATING THE USE OF A CERTAIN SYMBOL IN THE CALCULUS OF AFFECTED QUANTITY. The example selected was a demonstration of the Pythagorean Theorem by the aid of a new symbol. Mr. Marcus Baker presented a communication entitled A COLLECTION OF FORMULZ FOR THE AREA OF A PLANE TRIANGLE, which elicited some criticism of details and of notation. [This paper is published in full in the Annals of Mathematics, vol. 1, No. 6, and vol. 2, No. 1.] Mr. W. C. Wintock (by permission of Rear Admiral S. R. Franklin, Superintendent U. S. Naval Observatory) presented a communication on PHYSICAL OBSERVATIONS OF WOLF’S COMET (1884 III). [Abstract. ] The first observation of Wolf’s comet that I obtained was with the transit circle of the U. 8. Naval Observatory on September 24, 37 38 PHILOSOPHICAL SOCIETY OF WASHINGTON. 1884. The aperture of the instrument is 8 inches and the magni- fying power employed 186. . On October 13, using the 9-inch equatorial and a power of 182, “the comet seemed to bea circular nebulous mass with quite a well marked central condensation. The nucleus was not sharply defined, but blended gradually into the fainter light surrounding it.” Noy. 8. Transit circle. Nucleus quite well defined. Faint but not difficult to observe. Noy. 12. Transit circle. Nucleus elongated in the preceding fol- lowing direction and apparently composed of a number of bright points. Faint and difficult to observe. The nebulous envelope seems to extend farther on the upper or south side than on the lower side. Seeing, very poor. Nov. 13 with the 9-inch equatorial and the same power as before a sketch (omitted here) was made. The remarks I give sub- stantially as in my note-book: Watched the comet carefully for about an hour (seeing not very good,—a little fog hanging over the river). It is a very slightly oval nebulous object. The central part is a little condensed; the nucleus proper more so. Filar micrometer measures give for the extent of the outer nebula, meas- ured in the direction of a circle of declination, 1’ 52”, and for the inner disc 18”. The nucleus is perhaps extended a little in the preceding following direction, but I looked in vain for any indica- tion of the beaded appearance which I thought I saw last night with the transit circle. I might add that using the distance of the comet given in Kriiger’s ephemeris these measures would represent distances of 47,000 and 7,500 miles, respectively. No tail. Noy. 20. Transit circle. Nucleus stellar, 10th magnitude. On November 22 another observation was obtained with the 9-inch equatorial, magnifying power 132 as before. Micrometer measures of the outer nebula and the inner dise gave 1’ 30” and 16”, respectively, differing but little from the measures of the 13th. Seeing, fair. The following note was made: I divide the comet into three parts, the outer nebula, the inner envelope (or coma I presume it might be called), and the nucleus proper. It is almost impossible to assign a definite limit to this outer envelope, wavering and flickering like a mass of smoke, but the micrometer measures will fix it roughly. The inner envelope blends into the outer with- out any sharp division, though there is sufficient difference in bright- ness to attempt a measurement. The inner envelope condenses in turn into the brighter nucleus. MATHEMATICAL SECTION. . 39 Nov. 24. Transit circle. Nucleus sharp and stellar and about 10th magnitude. Dec. 2. Transit circle. Seeing poor. Extremely faint. Like a 12.5 magnitude star, surrounded by a large but faint nebula. Dec. 8. 9-inch equatorial and power 132. The diameter (in de- clination) of the outer envelope, from a micrometer measurement, was 2’ 21”, the seeing being noted a little better than on Noy. 22. Occasionally I think I see the inner condensed disc, but am not sure of it; also think that at times there is an indication of a more or less rounded outline to the head on the south preceding side, but it is unstable. Cannot be sure of anything like a tail, and indeed any definite form other than an irregular circle is, after all, largely a matter of imagination. The communication gave rise to some comment and discussion on the difficulties encountered in making satisfactory observations of faint comets and also on the resisting medium in space. Mr. Taytor called the attention of the Section to A SLIGHT MODIFICATION OF THE NEWTONIAN FORMULA OF GRAVITATION with which he had been struck in reading Mr. Bates’ paper on “ The Physical Basis of Phenomena” recently read before the General Meeting. (See vol. vii, p. 51.) [Abstract. ] There is a widespread fallacy—particularly displayed by those kinematists who fancy they have an exceptional insight into the “mechanism of gravitation,” that this influence is simply a radiant emanation, necessarily observing the geometry of radial space relations, having as such emanation the same total energy on all concentric spheres whatever their radii, as in the case of luminous radiation for example. Of course every well instructed astronomer and physicist knows that this is not so. In truth “the inverse square” is not geometrical—not a square at all, having no relation whatever to surface——kut simply an algebraical second power, very much like the familiar “velocity squared” (mv X 1, or momentum multiplied by velocity), which forms the measure of all kinetic energy and which no one supposes to represent a square. 40 PHILOSOPHICAL SOCIETY OF WASHINGTON. Our late colleague, General Alvord, in confutation of this not un- usual misconception, made a communication to the Society some two or three years ago (as those present doubtless remember) in which he showed that as gravitation was known to act equally on every particle of matter (7. e. proportionally to the mass) and as solid homogeneous spheres subtending any given conical angle from a center of reference possess volumes (or masses,—d being constant) directly proportional to the cubes of the conical altitudes or radii of distance, it follows—if gravity were a radial emanation—its effect must obey the law of inverse cubes of distance, contrary to the facts of observation. The fallacy here criticised springs evidently from the too common tendency to regard gravitation simply as a central force or as a single influence radial in direction, whereas it is always a duplex and reciprocal action; and however insignificant one of the terminal elements its presence and measure of distance cannot be neglected without completely nullifying all action. Thus m and m’ being two masses at any given distance apart, the action in the direction and through the distance m/’ m, is as real and positive as that in the direction and through the distance m m’. In other words, it would seem that the mutuality of the re-action necessarily involved with it the idea of reciprocity of the distance relation. Thus, adopting the suggestion of Mr. Bates, if we write the formula of the effect as (m +- d) X (m’ +d), we have this reciprocity distinctly brought out, and obtain at once the Newtonian formula. Thespeaker wished to learn from those more conversant than himself with mathemati- cal literature whether the suggested modification is new, and also whether any mathematical objection appears to its form. Mr. Hit remarked that one fault of the notation proposed ap- peared to be its want of generality, as it is evidently inapplicable to any other force having a higher or different exponent of the space function. Mr. Dooxtrr.e observed that, admitting the “reciprocity of the distance relation,” he yet failed to perceive how this function could appear in the formula as a product. Why should we write the dis- tance twice taken—as d multiplied by d rather than as d plus d? Further remarks were made by Messrs. Etuiorr, Bares, and ROBINSON. : MATHEMATICAL SECTION. 41 17TH MEETING. FEpRuARY 10, 1885. The Chairman, Mr, G. W. Hirt, presided. Present, eleven members and one guest. In the absence of the Secretary the reading of the minutes of the last meeting was deferred, and Mr. R.S. Woopwarp designated as Secretary pro tem. Mr. KuMMELL made a communication on AN ARTIFICE SOMETIMES USEFUL FOR THE ADJUSTMENT OF CONDITIONED OBSERVATIONS. [Abstract.] The general process consists in multiplying equations of condition by such factors as will extinguish side-coefficients in the normal equations for correlates. This was shown to be possible in an infinite number of ways. One such way leading to linear equations for the multipliers was shown to require for the extinguishment of all the side-coefficients the solution of the normals, 7. e., the very work which was to be evaded. The method would, however, be advan- tageous for the partial extinguishment of large side-coefficients, and the normal equations could thus be solved with advantage by Gauss’ indirect method. A useful symmetrical rule was given for extin- guishing the side-coefficients for a pair of conditions. Illustrations of this rule in the adjustment of simple geometrical figures were given, beginning with a simple figure of two triangles and extend- ing to a complete pentagon. Mr. Hixt remarked that Jacobi had proposed a similar method for removing side-coefficients. Further remarks were made by Mr. Woopwarb. The next communication was by Mr. Gustave L. RAVENE on THE THEORY OF MERCURY. [Abstract. ] The method here used of computing the secular variation of the elements of an orbit is dueto Gauss. 42 PHILOSOPHICAL SOCIETY OF WASHINGTON. The notation employed for the disturbed body is a t = longitude of perihelion ; = longitude of the ascending node; = inclination to the ecliptic ; = mean distance from the sun; = mean annual motion ; = eccentricity ; eccentric angle = arc sin ¢; = radius vector; = true anomaly ; = eccentric anomaly ; m = mass; and the same symbols with accents, =’, 6’, 7’, etc, rep- resent corresponding quantities for the disturbing body. From the definition of the secular perturbations, according to Gauss, the perturbing function may be expressed by 22 2x m’ 1 — e cose E V= fa f fA ae de 0 9O in which p is expressed by »%K,24 0.3 2 = I p? =a"? +r — 2dr cos (a, 7). We also have r =a’ (1— ecose)’ a'r cos (a’,r) = a’ cose” {cos m (a cos ¢ — ae) — a cos ¢ Sin « sin r} + a’sin < {a cos g sin e cosz + sinz(a cose — ae)}. Putting for brevity a’ (1 — ecose)? = pP, 2 {cos z (a cose — ae) — a cos gsin esin z} = 4, 2 {sin m(a@ cos ¢ — ae) + @ Cos ¢ SiN € Cos z} pa we get ey Ai) ae ’ A p= (a” + p.) — a (g, cose’ + 8 sin ’). The differential equation for the secular variation of the peri- helion is MATHEMATICAL SECTION. 43 mn’ cos ¢ 1—ecose = ’ — Tafa {4 aa oh ae, If we now put and also A =—acosz — ae cose cos7 + sin z sin ¢ € cos g a(2—e)., : CA ld IRI ge ta) forse te cos @ : , ae ; B =—asinz — ae cose sin z — ——— coszsin ¢ € cos 9 a (2—@é d : $ SC) os x sin © cos ¢ + 2a sin = cost 6 we obtain cig : in <” < =" Sae{a A, f= a 4B, Se ae } _we ry cose f S This expression contains the following integrals: Qn de’ = a R= {rep +. p,) —@ q, cose’ — a's sin aye c?) sa sin ¢’ de’ BAECs + p) —a@ q, cose’ — a's “sin oy}? cos < de’ dared Bes + p,) —@ q, cose’ — a's ain oy oO which must be computed for every value of © obtained by dividing the circumference into 7 parts. If we put a® +p. =; aq =¢ cos Q; a’ s = q sin Q, we get . {(@” + p,) —@ q, cose’ — a’ 8 sin e\-t = {1—q cos (e’ — a}? s lp 20," cos (c’ — Q) + oa.” cos 2 (c’ — Q) +--- 44 PHILOSOPHICAL SOCIETY OF WASHINGTON. The quantities ay, 4, a, etc., may be computed by Hansen’s for- mule given in his work, Auseinandersetzung, etc., 1 Abth., § 61, and wes found R, S, and T are found from the Seale R= 2a7; S = 2a,, sin Q; T= 2a,, cos Q. It would be interesting to know what influence the supposed intra-Mercurial planet would have on the other bodies of the system, especially on Venus. The differential equation of the motion of the ascending node is do 365.25 k dV dt ~ Ya+m)sini di’ The quantity & is the well known Gaussian constant, expressed in seconds of arc, and its logarithm is log k = 3.5500065746. The value of p’ is expressed by ep? =a? -+ a? — 2ad’ cos (a’, a) from which we have d(p*) ap , a[cos (a, a’)] Bis ae ain the di But cos (a, a’) = cos cose’ + sine sin <’ cos J, cos I = cosi cos?’ -++ sinisin? cos (0 — 0’), cot P sin (0 — 0’) — cot sini = — cos (0 — ) cost. Differentiating we get d® sin’? di sn (0—0) (cot i’ cos it + cos (0 — #) sin t) = ¢, We also have d any noe a = — cos?’/sini + cos isin? cos (0 — ”) = t,. From these expressions we obtain _d(cosa, a’) di and therefore d(p”) becomes = (— cos ¢’ sine + sin ¢’ cose cos I)t, + sin & sin ¢ t,, cial = p,cose’ + q, sin &’ in which p= 2aa’ sin « t,, and =— 2aa’ (cose cos I t, + sine ¢,). MATHEMATICAL SECTION. 45 TOMO P cote ; : : The expression 7; will in the actual computation be written in the form do 365.25 k m’ 0 dt Ya(l+m)sini2= ~~” in which j CG a Tp. > Sq. . , ° , , , 0 Nie Using the values 0’ = 14°36’, a’ = 0.200, 7’ = 7°,and m’ = a p9009 derived by me some time since for the intra-Mercurial planet, the perturbation of the node of Venus’ orbit is found to be 60 = — 3.92120 in a century. Mr. Hix, commenting on this paper, discussed briefly the prob- able mass and density of Mercury on grounds of probability and analogy, pointing out that its density would on such grounds appear to be far less than the ordinarily accepted value. 18tH MEETING. APRIL 15, 1885. In the absence of the Chairman, Mr. DooiTrLe was made Chair- man pro tem. Present, ten members and one guest. Minutes of the sixteenth and seventeenth meetings were read and approved. Mr. Marcus Baxer then read the following paper on A GROUP OF CIRCLES RELATED TO FEUERBACH’S CIRCLE. In any plane triangle the middle points of the sides and the feet of the perpendiculars drawn from the vertices to the opposite sides are six points in the circumference of a circle. This circle also bisects the segments of the perpendiculars between orthocenter and vertices, thus making nine noteworthy points. These properties 33 46 PHILOSOPHICAL SOCIETY OF WASHINGTON. . were first published in January, 1821, in Gergonnes’ Annales, vol. II, in a memoir by Brianchon and Poncelet on the determination of an equilateral hyperbola from four given conditions. In 1822 Prof. K. W. Feuerbach, of Nurenburg, showed that this circle is tangent to the inscribed and three escribed circles. This property is known as Feuerbach’s theorem, and the circle is known to the Germans as Feuerbach’s circle, In 1828 Steiner showed that this circle passed through twelve noteworthy points and was tangent to the in and escribed circles. This was done without a knowledge of the earlier work by Feuerbach. In 1842 Terquem, the editor of the Nowvelles Annales de Mathé- matiques, called it the nine-points circle. In some books it has been called the six-points circle. In an article, by myself, in the Mathe- matical Magazine for January, 1882, I have called it the twelve- points circle. Of the twelve points considered noteworthy six are in the sides of the triangle and six are not. If all the noteworthy points now known are to determine its designation, then twelve-points circle ap- pears to be a proper designation. If only those points in the sides of the triangle should determine the designation then six-points circle would appropriately name it. In either case nine-points circle would be an imperfect designation, and as the name Feuerbach’s circle was the first name it received it seems on the whole best to adhere to it. A somewhat analogous case is the seven-points circle known as Bro- card’s circle, not named for the number of noteworthy points it contains but for its discoverer. The name twelve-points circle may therefore be rejected and the name Feurbach’s circle adopted. The following proof of the fundamental properties of Feuerbach’s circle is offered as being simpler than that usually given: PRELIMINARY. 1. Definition. When we determine upon a right line AB a point Csuch that AC = BC = 2 AB the line is said to be bisected. This restricts us to one point C. Fig oy A C B Ge I t ! I It will be found convenient in what follows to extend this definition so as to include the points C’ and C”, Fig. 1, where AC= BC= AC’ = BC” = 3 AB; 1. ¢., by considering a der MATHEMATICAL SECTION. 47 nite line AB to be bisected when a segment equal to one-half the line is laid off from either extremity in either direction. 2. Theorem. The perpendiculars of a plane triangle meet in H, and, being prolonged to intersect the circumference in A’, B’, C’, the segments HA’, HB’ and HC’ are bisected by the sides of the triangle. (See Fig. 2.) Proof: AB’D = AHD = angle C. Notrre.—Here bisection is used in its ordi- nary sense. HZ is the orthocenter, and the theorem may be otherwise stated as follows: The segments of the perpendiculars included between the orthocenter and circum-circle are bisected by the sides of the triangle. The point of intersection of the medians is the eidocenter,* which we call G, and the well-known theorem that the medians are con- current and mutually divided into segments of which the greater is twice the less may be otherwise stated thus: T'he segments of the medians included between the eidocenter and vertices are bisected by the sides of the triangle. Note.—Here bisection is used in its extended sense. Using bisection in this extended sense it is therefore possible to unite these propositions into a single general statement, as follows: perpendiculars orthocenter The segments of the | at between the ROA ction away from towards the vertices are bisected and circumcircle measured | by the sides of the triangle. Thus in Fig. 3. ye oH=alL=}3 HI; and EP=};} EA; BH = §M =} HM; EQ =1 EB; 7H +N = § FN; ER = 3 EC. 3. Conceive the triangle ABC (Fig. 4) and 4@ its cireumcircle O to be the base of an oblique cone withinscribed tetrahedron. Let the ver- k tex of this cone be so taken that when the whole is projected * This term from etdog, form, and xévtpoy, center, has been ‘suggested by Mr. Henry Farquhar as being a more accurate derivation than the term centroid often used. It is, moreover, analogous to orthocenter, circum- center, etc. 48 PHILOSOPHICAL SOCIETY OF WASHINGTON. upon the plane of the base the projection of the vertex shall fall at the orthocenter H. Now let the whole be orthogonally projected upon the plane of the base. ~~ — a a From this conception it is seen that HA, HB, HC and HA’, HB', HC’ are projections of elements of the cone and HO the projection of the axis. Let the axis of the cone be bisected by planes parallel to the base. There are three such bisecting planes: one midway between apex and base, another below the base, and a third above the base. Finally let all these sections be orthogonally projected upon the plane of the base. From these conceptions it follows immediately that— (a.) These projections are circles whose diameters are, respect- ively, 2, #, 3, the diameter of the circumcircle. (b.) The centers of these circles F, F’, F”, all lie in the line HO, MATHEMATICAL SECTION. 49 joining the circumcenter to the orthocenter, and are points of bisection, in the ordinary and extended sense, in such manner that i= FO = PO — FF" A FO. (c.) The segments of the perpendiculars HA, HB, HC, and HA’, HB’, HC’ are all bisected by each of these circles. In the case of the first circle F, the segments are bisected in the ordinary sense, and since the segments HA’, HB’, and HC’ are also bisected by the sides of the triangle this circle passes through the feet of the per- pendiculars. The points of bisection on the perpendiculars determined by the circle F are points of bisection in the ordinary sense. The points of bisection on the perpendiculars determined by the 7 circle | are points of bisection in the extended sense, and in such Wise that the segments cut off from A and A’, B and B’, Cand towards away from the vertices. C’ are measured from the orthocenter | (d.) Every line drawn from # to the circumcircle is bisected by the three circles F, F’, and #’”’. His therefore a direct center of similitude common to the circles O, F, and F” and an inverse center of similitude common to all four circles. 4. The eidocenter is collinear with the circumcenter, orthocenter, and Feuerbach center*; for from a known theorem we have HB = 2 OM, and therefore HO must divide BM into segments of which the greater is twice the less, 7. e., it must pass through the eidocenter. 5. Again conceive the triangle ABC (Fig 5) as the base of an oblique cone, etc, as in section 3, except that its vertex is to be con- ceived as perpendicularly over the eidocenter instead of over the orthocenter, and the whole projected as before. In this case KA, EB, EC,and EA’, EB’,EC’ are projections of the elements of the cone and EO, coincident with HO from section 4, the projection of the axis. Let the axis be bisected as before by three planes parallel to the base: one midway between apex and base, another below the base, and a third above the apex, and the sections so formed projected upon the plane of the base. * The center of Feuerbach’s circle may be so called for brevity. 50 PHILOSOPHICAL SOCIETY OF WASHINGTON. We then have— . (a.) These projections are circles whose diameters are, respect- ively, 2, $, and 4, the diameter of the circumcircle. (b.) The centers of the circles fF”, F’”, F all lie in EO and there- fore in HO joining circumcenter to orthocenter and are points of bisection of HO in both the ordinary and extended sense in such Wise that Fy Sih "Ol Sa = Bae (c.) The segments of the medians EA, EB, EC and EA’, EB’, EC’ are all bisected by each of the circles. In the case of the third circle F, the segments are bisected in the eatended sense, and since the segments of the medians, EA, EB, EC, are also bisected in the extended sense by the sides of the triangle the,cirele F bisects the sides of the triangle. The points of bisection on the medians determined by the circle F”’ are bisections in the ordinary sense. MATHEMATICAL SECTION. 51 The points of bisection on the medians determined by the circles wt ry | yf are points of bisection in the extended sense, and in such manner that the segments cut off from A and A’, B and B’, C and towards away from (d.) Every line drawn from £ to the circumcircle is bisected by the three circles F’”’, F’”’, F'; E is therefore a direct center of simili- tude common to three circles O, F”, F’” and an inverse center of similitude common to all four circles. OC’ are measured from the eidocenter i the vertices. 6. If we now compare figures 4 and 6 and consider the three circles in each which resulted from projection, we find that circle F, and only circle F, is identical in the two figures. This identity appears from the fact that their diameters are equal, each equaling half the diameter of the circumcircle, and their cen- ters coincident. The coincidence of their centers appears from drawing the projections of the axes of the cones side by side, thus: O F Lik _——— From Fig. 4. |———— - —- ve From Fig. 6. O E F From Fig. 4 we find that this circle, Feuerbach’s, passes through 6 noteworthy points, being 2 points on each perpendicular; and from Fig. 6 we find that the same circle passes through 6 other noteworthy points, being 2 on each median, or in all Feuerbach’s circle passes through 12 noteworthy points. 7. It is apparent from the foregoing that if we should not bisect the axis of the cone but should cut it in any ratio (Fig. 4) by a plane parallel to the base then the projection of the section would bea circle cutting the perpendiculars in that ratio and its center F, would divide HO in that ratio. The medians would not be divided in that ratio, but a point in HO exists (ca!l it E,) through which, if lines be drawn from the vertices to the opposite sides, these lines would be divided in the given ratio. The four points O, En, /,, H would in this case, as before, be four harmonic points. 8. Since Feuerbach’s circle bisects the sides of the triangle it is the circumcircle of a triangle similar to the original and of half its 52 PHILOSOPHICAL SOCIETY OF WASHINGTON. size. The results here deduced may therefore be considered to be results of a comparison of the circumcircles of these two triangles. A corresponding study of the relations of the tangent circles (in- and escribed) would therefore be expected to yield many more properties as there are four times as many circles to be considered. Concerning the phrase “bisection in the extended sense,” Mr, Dooxirr Lez suggested that the term “sesquisection ” might be advan- tageously employed. As to the name “nine-points circle,” Mr. KuMmMELL said that it was plainly defective, either “ six-points” or “twelve-points ” circle being satisfactory, according to the point of view taken, but that nine-points circle was not a correct desig- nation from any point of view. Further remarks were made by Mr. Exxiorv. Mr. C. H. KumMe tt presented a communication entitled DISTANCES ON ANY SPHEROID. [Abstract. ] The present form of solution of the problem to determine the shortest distance between two points on a spheroid which are given by their latitudes and longitudes is characteristic in making use of the Gaussian algorithm of the arithmetico-geometric mean. This and a corresponding transformation of the amplitudes give the necessary elements for computing in three terms the distance precise to the eighth order at lJeast. The form is also remarkable for its symmetry and easy extensibility to still higher precision. Also the preliminary part of the problem in which the excess of the spherical longitude over the spheroidal is determined by succes- sive approximations is much facilitated by the introduction of an angle 7, which is closely related to ¢, the angle of eccentricity, and which varies between 0 and «. It was thus possible to express the excess of spherical over spheroidal longitude in one term, precise to the 6th order at least. [This paper has been published ig full in the Astronomische Nachrichten, No. 2671.] ; In reply to a question, Mr. KuMMELL said that the®rdinary for- mulz for computing distances between intervisible points on the terrestrial spheroid are all that can be desired. The formulse here MATHEMATICAL SECTION. 53 presented, however, are designed for much greater distances and for any spheroid, and would serve, if need ever arose, for comput- ing the shortest distance between any two points on the terrestrial spheroid no matter how remote. 19TH MEETING. APRIL 29, 1885. The Chairman, Mr, G. W. Hitt, presided. Present, nineteen members and one guest. Minutes of the eighteenth meeting read and approved. Mr. A. Zriwer read a paper entitled ON GRASSMANN’S SYSTEM OF GEOMETRY. This paper will appear in full in the Annals of Mathematics, vol. 2, Nos. 1 and 2. In reply to a question by Mr. Curtis as to whether Grassmann’s system could be advantageously substituted for the Cartesian sys- tem, Mr. Zrwet expressed the opinion that it could not be so sub- stituted in general, but that it might in certain special cases. Grassmann has not, said Mr. ZiwET, made applications of his method to astronomy, nor indeed does its value consist in its adaptability to the solution of special problems. But for present- ing general geometrical truths it appears superior to Hamilton’s methods, to which it is closely related and with which it might be advantageously joined. Mr. Haut remarked that he had seen planetary orbits worked out after Hamilton’s method by J. Willard Gibbs, but the process appeared rather more laborious than the usual Gaussian one. The labor of computation of results, Mr. Hitt remarked, was practically the same by all methods. By introducing the needful symbols the general expressions may be made exceedingly simple, but when the numerical work begins it will be found that after par- ing off more or less extraneous matter there still remains a central kernel or core of computation from which there is no escape by any method whatsoever. With this view Mr. R.S. Woopwarp heartily concurred, and added that the supreme test of the usefulness of such systems as 54 PHILOSOPHICAL SOCIETY OF WASHINGTON. Grassmann’s, Hamilton’s, ete., consists in their ability to reveal new truths; a test which, according to Mr. Ziwet, Grassmann’s system successfully stands. Mr. M. H. DooxirtLe presented a communication on CAUSE AND CHANCE IN THE CONCURRENCE OF PHENOMENA. The author’s views set forth in this communication were stated to be preliminary and incomplete, and he therefore reserves them to be more fully elaborated before publication. 20TH MEETING. May 18, 1885. The Chairman, Mr. G. W. H111, presided. Present, eleven members and three guests. Minutes of the nineteenth meeting, read, corrected, and adopted. Mr. G. L. RAVENE read a paper entitled THE ASTEROIDS. This communication elicited a general discussion, participated in by Messrs. KumMELL, Rirrer, BAKER, WoopwArD, ELLIorT, Pau., and HI. Mr. Rirrer then read a paper on SECULAR PERTURBATIONS OF POLYHYMNIA BY JUPITER, [Abstract. ] In the computations of these perturbations Gauss’s method has been employed, using the formule adapted to facilitate the appli- cation of this method given by Mr. G. W. Hill. The eccentricity of Polyhymnia being very large the circum- ference, with reference to the eccentric anomaly of Polyhymnia, has been divided into twenty-four parts. This is a greater number than necessary, but it seemed worth the additional labor required to have the forces and the other quantities involved for as large a number of points as practicable. MATHEMATICAL SECTION. ae The epoch for both systems of elements is 1873, July, 17.0, Berlin mean time. The ecliptic and mean equinox are for 1873.0. The resulting secular variations in one Julian year are the fol- lowing: Secular variation of the eccentricity, or de== + 1.268; . “ ~~ inelination, or oi=— 1.649; 3 “ ascending node, or 62 = — 61.031; is “ ~~ longitude of the perihelion, or dz = + 59.116; > “ mean longitude, or 6D = — 83.429; The paper was discussed by Messrs. PAuL, H1Lu, and Woop- WARD. 2ist MEETING. May 27, 1885. The meeting was called to order at 8:15 by the Chairman, Mr. G. W. Hitt. Seventeen members present. At the request of the Chair Mr. Wintock acted as secretary pro tem., Mr. BAKER being absent. Mr. R. 8. Woopwarp read a paper on SOME PRACTICAL FEATURES OF A FIELD TIME DETERMINATION WITH A MERIDIAN TRANSIT. [ Abstract. ] An important desideratum in all kinds of field work is the adoption of those methods which will secure the accuracy essential in the results sought with the minimum amount of computation. It is in general easier and more conducive to precision to eliminate unnecessary factors involved with the quantity sought than to determine their values and allow for them by computation. Very frequently also a systematic arrangement of observations will secure the maximum precision with the minimum of computation. In a field time determination for telegraphic longitude’ the essen- tial quantity is the error of the time-piece used at some determinate epoch, and the unessential factors are the azimuth and collimation of the transit and the rate of the time-piece. It is evident that a 56 PHILOSOPHICAL SOCIETY OF WASHINGTON. minimum of computation will be required if the observations can be so arranged as to eliminate the effect of these factors in the final value of the correction to the time-piece. Although it is usually im- possible to eliminate the effect of the azimuth, collimation, and rate completely, it is generally possible to make a close approximation thereto. To show this fact analytically let = the correction to the time-piece at the epoch ¢,; = the observed time of a star’s transit; = the star’s right ascension; = the azimuth of the transit; = the collimation of the transit; = the rate of the time-piece; the azimuth factor ; = the collimation factor; = the weight of (¢ — 4); = the residual error. Saif. 3 fen | Then the type observation-equation will be at+ Aat+tCce+t—t)r+ti-—-a=v». (1) The normal equation in At, using brackets to indicate summation of like quantities, is [p]4t+[pA]a+[pCl]e+[pG@—t)]r+ [pG—a1= 0. (2) ~ This shows that in order to secure the complete elimination of the effect of a, c, and r, we must have [pA] = 0, [pC] = 0, [p ¢@ — t.)] = 0. (3) The last of these conditions can always be fulfilled by making fe Lee) bij seit re It may be shown that the value of A¢ corresponding to ¢, as defined by (4) has a maximum weight. A close approximation to the first two conditions of (3) can be secured by selecting for obser- vation stars of suitable declinations and by reversals of the tele- scope. If we put Load sy ee Lee behets) aL se? equation (2) gives At = — At, — Ba—jye. (5) This shows that in case # and y are small, as supposed above, an MATHEMATICAL SECTION. 57 approximate value of At is — At,. After some preliminary obser- vations at a station it is easy to render a and ¢ small, and their ap- proximate values may always be found from the observation equa- tions by a brief inspection; so that with such values of a, c, #, and y as are nearly always readily attainable At may be derived from (5) to the nearest 0°.01. We may thus dispense entirely with the other three normal equa- tions and reach the same result which would follow from their use. The solution may also be checked; for by one or two approxima- tions the values of At, a and ¢ which make [pv] = 0 can be readily found. The practical steps in deriving 4¢ from (5) may be summarized as follows: 1. The mean of the observation-equations for clamp west minus the mean of those for clamp east will give an approximate value of the collimation c. 2. The application of this value of ¢ to each observation equation will give a corrected value of (¢ — a) for each star. 3. An approximation to the value or values of the azimuth will then result by eliminating At from one or more pairs of the corrected observation equations. The azimuth may then be applied to correct the values of (¢ — a), reached in step 2. 4. The approximate values of a and ¢ will now give an approxi- mate value of At from (5), and the application of this value of At to the values of (t — «), derived in step 3, will give approximate values of v. 5. Form [pv]. If this sum is not zero within 0°*.01 or 0°.02, a brief inspection will show what changes in a and ¢ (and _ possibly At) will make it zero within those limits. By this process of determining the residuals or their approximate values as soon as possible in the computation any large errors in the values of (£ — a) or the azimuth and collimation factors will be easily detected. In precise longitude determinations it is customary to have for each night’s observations two complete time determinations, one immediately preceding and one immediately following the tele- graphic comparison of time-pieces. In this case there will be two values of A¢. Calling these At’ and At’ and denoting the corres- 58 PHILOSOPHICAL SOCIETY OF WASHINGTON. ponding epochs by ¢,/ and,” the rate of the time-piece will be given with sufficient accuracy for interpolation by the equation At” — at’ Mr. Paut thought it an objection to this method that in arrang- ing the groups valuable stars might be lost, so that in a limited time the accuracy of the results would be impaired by the smaller number of observations ; moreover, the method did not furnish the computer with a clear idea of the performance of the instrument. Mr. Hatz said that he liked the method, and that he thought it especially good for time work. He had discovered the method once himself, and he knew that it had also been used by Prof. Ormond Stone. Mr. KumMeE t said that in connection with this subject he had investigated the question of the advisability of using stars towards the pole for time determinations; that is, he had examined the weight co-efficient formule to see at what distance north of the zenith a maximum value would be obtained. He found that in general the limit of declination was about 60°. Mr. Paut thought that every weight-formula should take account of the increase of atmospheric disturbance with increase of zenith distance. T= Mr. KumMe t then read the following paper entitled CAN THE ATTRACTION OF A FINITE MASS BE INFINITE? In Price’s Calculus, vol. III, art. 201, discussing the result for the attraction of a thin rectangular plate on a particle external to it and in its own plane it is found that if the attracted particle is at an angle of the rectangle the attraction is infinite. Price’s method of determining the attraction of plates consists in integrating be- tween the proper limits the following differentials : ax = Se qd ) (a? + y')° ‘ a’ Y = mor es Es 3 (a? ue y’)” y where X = x — axial component of attraction; Y = y — axial component of attraction; = mass of attracted particle ; 6 = density of attracting mass, supposed homogeneous ; t = thickness of the plate. MATHEMATICAL SECTION. 59 Referring to the attracted particle as origin let (a,, 6,) be the corner nearest and (a,, b,) that farthest from the particle; then Ba: “ a CaAXL vg = mdr SoS ce ob y)? Q, b, = mot y dy ((a, = yy? — (a? + )) | b+ (at +52)? b+ (a2 +5) = mor] 4 WEA Ee A b, + (a? +67)" b+ (a? + b,”)° and a similar expression for Y by exchanging the a’s for the b’s. (2) If in this we place a, = b, = 0 then X= moro. This is taken by Price to be infinite; yet, since the thickness t must be taken infinitesimal, this is an entirely unfounded conclu- sion, At first, however, I did not suspect this result, and when Mr. Woodward found an infinite attraction of a circular disk on a point at its circumference, which result I checked, it seemed to be possible that the attraction of a finite mass could be infinite. Yet neither Mr. Woodward nor myself was entirely convinced. To settle this question I then resolved to determine the attraction of a right ‘prism and also of a right circular cylinder ona particle at mid- height, which, being then moved to the surface and taking the height infinitesimal, would give the attraction of a plate on a par- ticle in a position at which an infinite attraction had been found. For a right rectangular prism we have, 2A being its height, By ha h dr x= a hay: adx Serer! ° a, ~ b, 2Qhadx wed J. WerpetyTr Si ° a, Comparing this with (2), putting 2h = t, we readily see that these values are by no means identical, for (2) is of the form tf, (a,, @,, b,, b,) while (8) is \ ——— then ¢ has the limits _| and a — p a b? 0. Wehave then p? + ? = Few ae ae where Ag Se is an elliptic A function to the modulus | jee S Transform- ing we have, expressing in A functions ? (1 — d¢’) (a¢’ —-, A= amo 1 ab? ay _ A¢g ?— hag’ 0 ab? te dg = dg (#— iy. dy | amd a} at) apt fa a ae eh ; 9 Um 49) a9} b? | , dg Rh = 2md77 | fx-Bs¥ Ag Lo 0 ft] } (d + r) dg | mae f 4rdh? 0 (1 + a (d— ry sin *0) Ag | = amo | Fe EH (4) (S45) fe where fF, E, and J/ denote quadrantal elliptic integrals of the 1st, 2d, and 3d species, according to Legendre’s notation. If our object was to obtain here a formula for convenient computation of the attraction the third term could still be expressed in integrals of the 1st and - species, which have been tabulated by Legendre, 62 ‘ PHILOSOPHICAL SOCIETY OF WASHINGTON. Let us now move the particle to the surface of the cylinder, then we have d= 7; a= 7/4r* +17; b =h, and (6) becomes ah A’ = 2m0 —- (F— E). (6’) Mr. Woodward, as already stated, had found an infinite attrac- tion of a circular disc on a particle on its circumference by using Price’s method. Now, since A’ is surely a finite quantity, we have here the manifest absurdity that the attraction of a cylinder on a particle on its surface would be’ less than that of a circular disk which is only an infinitesimal part of it. If we wish to ascertain the attraction of a circular disk of finite small thickness we may, of course, use (6’), and since then F’ tends to infinity, E may be neglected; therefore - d A’ _ 2mé ah f = are Nats af — sin? ) 7 ae h=o0 oy = 4m0 i h? h=o me 47? af sin *9 dg a* Ag® = 4m - Th h=o0 = 0 - Since then the attraction is 0 if A = 0 it will be small if h is small, and will continuously grow with h. MATHEMATICAL SECTION. 63 The notion of an infinite attraction exerted by a finite mass has thus been dispelled in two special cases in which it seemed to have been proved, and I add some remarks on its general impossibility. The attraction of a mass element on a particle at distance p is dx dy dz me ——— , i This is then an infinitesimal of the third order, and the summa- tion of its components with respect to a fixed direction requires three integrations, which give surely a finite result if p is always finite. If p is infinitesimal there will be one element of attraction, which, instead of being of the third order, is only of the first order of in- finitesimals, and this one element being added to the finite sum of the other elements has no effect. Hence I conclude that a finite mass exerts only a finite attraction on a particle. The paper was discussed by Messrs. Hati, HiLy, and Woop- warp. Mr. Woopwarp said that he had arrived at a result simi- lar to Mr. Kummell’s by a somewhat different route. The fallacy in Price’s Calculus arose from neglecting the thickness of the plate. Nore. The communications and abstracts printed in the proceedings of the Mathematical Section have each been examined by a special committee consisting of the Chairman, the Secretary, and a third member appointed by the Chairman. These third members were as follows: Title. Author. Third Member. Physical observations of Wolf’s comet-W. C. Winlock, — — — The Theory of Mercury_---____-_____G. L. Ravené. E. B. Elliott. A group of circles related to Feuer- ee SG C1TC1O a Marcus Baker. C. H..Kummell. Some practical features of a time de- FOLIATION soso ne eae —R.S. Woodward. H. Farquhar. Can the attraction of a finite mass be MOH ILE Me eee ee ko Oe Kummells,. Rt on Woodward: nae ie phe Poe ih ee oa uy i PD Exe Page. Abbe, C.: communication on methods of verifying weather predictions...........06 . 8,9 Adams, C. F., Election to membership of...... 17 Adjustment of conditioned observations...... 41 American Academy of Arts and Sciences..xxxvi ' American Association for the Advancement PSHE GIO CO sn sdeasteascansnavasssxeaccaselscssseierast Xxxix American Philosophical Society...xxxiv, xxxvii American scientific societies.........ccccee. + Xxxili Annual address of the President...... .........XxX Xi Annual meeting.....cccesseeeees eatserseatcoatiegeacesay = 30 Anthropological Society, Invitation from...... 5 Anthropometric and reaction-time apparatus 25 Antisell, T.: remarks on the nature of odors 27 — — — thunderstorMms.....ce.sccssssersecseseecesees 11 Artifice sometimes useful for the adjustment of conditioned observations.............eceeee 41 Attempt at a theory of OdOT............00cceceesceees Q7 Attraction, Infinite, of a finite mass.............. 58 Auditing committee, Appointment of........... 31 BeBILE DOLL Ol ic cascucies suabsvine cydecesns csavecccasacseaes yen; Baker, Marcus: communication on a group of circles related to Feuerbach’s circle.. 45 ———a collection of formule for the area Misa Plane tIANS] O.)-.52ccessencsssacseveocsconeaixs 37 — elected Secretary of Mathematical Section 387 —report of auditing committee.............ces 3 Baker, Frank: communication on modern ideas of brain mechanism... Siachenirncesl ae — remarks on the recognition a like ieee BEATA GES OUT. soescecce ls eeauasnnystaedicsanarn csstecaces 13 Barus, Carl, Election to membership of....... 5 Bell, A. G.: communication on the m@than- ism of “clicks” and “clucks”’...........0008 18 Billings, J. S.: communication on anthropo- metric and reaction time apparatus....... 25 ——-— germ cultures........ Soe spesuevens daveccaasc see 30 — — — Vital statistics of the tenth U. S. DETUSITS sc nsavvanesaonsalasucansenasenciub ewes senscnkrecssea 4 — remarks on the olfactory sense organs..... 28 ————— CATS Of PAM Ph ]Ots........cscse-cecscseseceese » 29 Biological Society, Invitation from ....... 4 Brown, Addison, cited on ahertetions “of UTENNL lst tecceaceccct sv sai'sesisaainoevelibewwes veceeskeameaaly 12 Bulletin, Rules for pulication of.............0 xiii Burnett, S. M.: communication on the Javal and Schiotz ophthalmometer.................. 11 Capron, Horace, Death of............ Budcsbenppaesenstd a Cause and chance in the concurrence of phe- TVOMI OT Avi revcapseeopuedesadapenncs bencataueees ADDRESS AND RESIDENCE. Department of Agriculture. 1918 Sunderland Place, N. W. Geological Survey. Cosmos Club. Coast and Geodetic Survey Office. 55 C st. 8. E. Army Signal Office. 1736 13th st. N. W. Internal Revenue Bureau. National Museum. 1305 Q st. N. W. Surg. General’s Office, U. 5S. A. 1239 Vermont ave. Terre Haute, Ind. Department of Agriculture. 1912 Sunderland Place, N. W. National Museum. 1602 19th st. N. W. Coast and Geodetic Survey Office. 1331 L st. N. W. 918 E st. N. W. Coast and Geodetic Survey Office. National Museum. 1441 Chapin st., College Hill. Navy Department. 941 M st. N. W. Bloomingdale Asylum, Boule- vard and 117th st., New York, Nay. Topographer, P. O. Dept. 2109 G st. N. W. 1731 K st. N. W. Vancouver Barracks, Wash. Ter. Court of Claims. 826 Connecticut ave. N. W. Coast and Geodetic Survey Office. 1324 19th st. N. W. 212 Delaware ave. N. E. Engineer Bureau, War Dépt. 16 Lafayette Square. 2 Lafayette Square. Davenport, Lowa. Year of admission. 1885 1884 1886 1885 1878 1875 1884 1871 1885 1886 1884 1886 1883 1885 1884 1871 1872 1871 1879 1884 1885 1884 1878 1871 1871 1871 a LIST OF MEMBERS. XXIII 35 Name. ADDRESS AND RESIDENCE. a2 aE <4 Pav, Mr. H. M. (Henry Martyn) | Naval Observatory. 1877 109 Ist st. N. E. PxEALE, Dr, A. C. (Albert Charles) | Geological Survey. 1874 1010 Mass. ave. N. W. Por, Gen. O. M. (Orlando Met- | 34 West Congress st., Detroit, | 1873 calfe) U.S. A. (Absent) Mich. PoinpEexTER, Mr. W. M. (William | 1505 Pennsylvania ave. 1884 Mundy) 1227 15th st. N. W. Porx, Dr. B. F. (Benjamin Frank- | Surg. General’s Office, U. 8. A. | 1882 lin) U.S. A. Powet.t, Major J. W. (John | Geological Survey. 1874 Wesley) 910 M st. N. W. Prentiss, Dr. D. W. (Daniel | 1101 14th st. N. W. 1880 Webster) Pritcuett, Prof. H. S. (Henry | Director of Observatory, Wash. | 1879 Smith) (Absent) University, St. Louis, Mo. RatTHBuUN, Mr. RicHarpD Smithsonian Institution. 1882 1622 Mass. ave. Bari t Lieut. P. H. (Patrick Henry) | Fort Gaston, Cal. 1884 ey = ac, Mr. Jno. H. (John | Geological Survey. 1883 Henry) 1512 Kingman Place. RicksEecKER, Mr. EuGENE Geological Survey. 1884 1323 Q st. N. W. River, Dr. C. V. (Charles Valen- | Agricultural Department, or 1878 tine) National Museum. 1700 13th st. N. W. Ritter, Mr. W. F. McK. (William | Nautical Almanac Office. 1879 Francis McKnight) 16 Grant Place. Ropinson, Mr. THoMas Howard University. 1884 6th st. N. W., cor. Lincoln. Rocrrs, Mr. Josrpu A. (Joseph | Naval Observatory. 1872 Addison) (Absent) eau Mr. IsraEt C. (Israel | Geological Survey. 1882 ook) Russe.i, Mr. THomas ’ | Army Signal Office. 1883 1447 Corcoran st. N. W. Satmon, Dr. D. E. (Daniel Elmer) | Agricultural Department. 1883 12 Iowa Circle. Sampson, Commander W. T. (Wil-| Naval Academy, 1883 liam Thomas) U.S. N. (Absent) Annapolis, Md. SavItte, Mr. J. H. (James Ham-| 1419 F st. N. W. 1871 ilton) 1315 M st. N. W. Scnorr, Mr. Coaruzs A. (Charles | Coast and Geodetic Survey Office.| 1871 Anthony) (Founder) 212 Ist st. S. EH. SHELLABARGER, Hon. SAMUEL Room 31 Kellogg Building. 1875 812 17th st. N. W. SHERMAN, Hon. JoHN U.S. Senate. 1874 SHUFELDT, Dr. R. W. (Robert Wilson) U.S. A. (Absent) 1319 K st. N. W. Surg. Gen’l’s Office, U. S. A., or| 1881 Box 144 Smithsonian Inst. XXIV PHILOSOPHICAL SOCIETY OF WASHINGTON. NAME. Sr1asBEE, Commander C. D. (Charles Dwight) U.S. N. (Ad- sent) Sxinnepr, Dr. J. O. (John Oscar) U. 8. :As Smrtey, Mr. Cas. W. (Charles Wesley) Smita, Chf. Eng. Davin, U. Si IN. SmitH, Mr. EDWIN Snevu, Mr. Merwin M. (Merwin Marie) SporrorD, Mr. A. R. (Ainsworth Rand) Srearns, Mr. Ropert E. C. (Rob- ert Edwards Carter) Strong, Prof. ORMoND (Absent) Taytor, Mr. F. W. (Frederick William) (Adsent) Taytor, Mr. WILLIAM B.( William BoweEr) (Founder) Tuompson, Prof. A. H. (Almon Harris) Tuompson, Mr. GILBERT Topp, Prof. Davip P. (David Peck) (Absent) Toner, Dr. J. M., (Joseph Mere- dith) TrenuoLM, Hon. WILLIAM L. (William Lee.) Truez, Mr. FREDERICK W. (Fred- erick William) Urron, Mr. Wm. W. (William Wirt) Urrton, Prof. WINSLow (Absent) Watcort, Mr. C. D. (Charles Doolittle) Waxpo, Prof. Frank (Absent) Waker, Mr. Francis A. (Fran- cis Amasa) (Absent) Watuine, Mr. Henry F. (Henry Francis) (Absent) Warp, Mr. Lester F. (Lester Frank) ADDRESS AND RESIDENCE. Navy Department. Surg. General’s Office, U. S. A. 1529 O st. N. W. U.S. Fish Commission. 943 Mass. ave. Navy Department. Coast and Geodetic Survey Office. 2024 Hillyer Place. National Museum. 715 Mt. Vernon Place. Library of Congress. 1621 Mass. ave. N. W. Smithsonian Institution. 1635 18th st. N. W. Leander McCormick Observa- tory, University of Virginia, a Care Smithsonian Institution. Smithsonian Institution. 806 C st. N. W. Geological Survey. Geological Survey. 1448 Q st. N. W. Amherst College Observatory, Amherst, Mass. 615 Louisiana ave. Controller of the Currency. 1812 N st. N. W. National Museum. 1835 N st. N. W. 1416 F st. N. W. 1746 M st. N. W. -Brown University, Providence, Geological Survey; National Museum. Army Signal Office, Fort Myer, Va. Massachusetts Institute of Tech- nology, Boston, Mass. U.S. Geological Survey, Cam- bridge, Mass. Geological Survey. 1464 Rhode Island ave. Year of admission 1879 1883 1882 1876 1880 1886 1872 1884 1874 1881 1871 1875 1884 1878 1873 1886 1882 1882 1880 1883: 1881 1872 1883 1876. LIST OF MEMBERS. XXV NAME. WeEssTER, Mr. ALBERT L. (Albert Lowry) (Absent) WEED, Mr. WALTER H. (Walter Harvey) WELLING, Mr. James C. (James Clarke) WHEELER, Capt. Guo. M. (George Montague) U.S. E. Wuite, Dr. C. A. (Charles Abia- thar) Waite, Dr. C. H. (Charles Henry) U.S. N. Wituts, Mr. BAILEY Witson, H. M. (Herbert Michael) Witson, Mr. J. ORMoND (James Ormond) Win tock, Mr. WiLi14M C. (Wil- liam Crawford) Woop, Mr. Josepy (Absent) Woop, Lt. W. M. (William Max- well) U.S. N. (Absent) Woopwarp, Mr. R. S. (Robert Simpson) WortMay, Dr. J. L. (Jacob Law- son) Wrieut, Mr. Gro. M. (George Mitchell) (Absent) Yarrow, Dr. H. C. (Harry Crécy) Yeates, Mr. W. S. (William Smith) ZiweEtT, Mr. ALEXANDER ZuMBROCK, Dr. A. (Anton) 36 ADDRESS AND RESIDENCE. 107 Drexel Building, Broad st., New York city; West New Brighton, Staten Island, N.Y. Geological Survey. ‘The Grammercy ’’, Vermont ave. 1802.Sonnecticut ave. Lock Box 93. 930 16th st. N. W. Geological Survey. 312 Maple ave., Le Droit Park Museum of Hygiene, 1744 G st. NeW Geological Survey. 1823 H st. N. W. Geological Survey. 1439 Massachusetts ave. N. W. Naval Observatory. 718 21st st. N. W. Supt. Motive Power, Penn. Co., Fort Wayne, Ind. Navy Department. Geological Survey. 1804 Columbia Road. Army Medical Museum. 1711 13th st. N. W. Akron, Ohio. Surgeon General’s Office, U.S. A. 814 17th st. N. W. Smithsonian Institution. 1403 6th st. N. W. Coast and Geodetic Survey Uftice. 140 C st. 8. EH. Year of admission. 1882 1885 1872 1873 1876 1884 1885 1885 1878 1880 1875 1871 1888 1885 1885 1874 1884 1885 1875 XXVI PHILOSOPHICAL SOCIETY OF WASHINGTON. LIST OF DECEASED MEMBERS. Name. Benjamin Alvord Orville Elias Babcock Theodorus Bailey Joseph K. Barnes Henry Wayne Blair Horace Capron . . Salmon Portland Chase Frederick Collins Benjamin Faneuil Craig. : : : Charles Henry Crane . - : g ° Josiah Curtis ; Richard Dominicus Cutts Charles Henry Davis Frederick William Dorr Alexander B. Dyer . Amos Beebe Eaton . Charles Ewing Elisha Foote - John Gray Foster . Leonard Dunnell Gale . Isaiah Hanscom Joseph Henry Franklin Benjamin Hough Andrew Atkinson Humphreys Ferdinand Kampf Washington Caruthers Kerr Jonathan Homer Lane f 5 : - : Oscar A. Mack . . : . . . Archibald Robertson Marvine Fielding Bradford Meek : James William Milner ; : . Albert J. Myer . George Alexander Otis Carlile Pollock Patterson Titian Ramsay Peale Benjamin Peirce John Campbell Riley John Rodgers . Benjamin ‘Franklin Sands George Christian Shaeffer Henry Robinson Searle William J. Twining . Joseph Janvier Woodward John Maynard Woodworth Mordecai Yarnall : SUMMARY. Active members Absent members : ; c . 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Swen ieA ALORS VATE bak nm ery Suh, Sly ah gt = = ty 5 . 7 Bip bed iy _e eo —— : ti mueratt Satin, wt up Loe, Se a SECRETARIES’ REPORT ped 6d ANNUAL REPORT OF THE SECRETARIES. Wasuineron, D. C., December 18, 1886. To the Philosophical Society of Washington : We have the honor to present the following statistical data for 1886: The last Annual Report brought the record of membership down to January 16, 1886. The number of active mem- bers wasthen . . . ; : : : } fa HS This number has been increased by the addition of 18 new members, by the return of 1 absent member, and by the reinstatement of 2 members previously dropped. It has been diminished by the departure of 9 members, by the resignation of 1, and by the dropping of 7 for non-pay- ment of dues. There has been no death. The net in- crease of active members has thus been . ; : : 4 And the active membership is now. i ‘ 5 2) ESS The roll of new members is: N. L. Batss. J. C. Gordon. MarsHALL McDona.Lp. H. G. BEYER. Lid NS ae oy ARTEMAS MARTIN. J. H. Bryan. W.F. HILLEBRAND. C. H. Merriam. G. J. CUMMINGS. R. D. Irvina. Henry MITCHELL. CooPER CURTICE. C. A. KENASTON. M. M. SNELL. N. H. Darton. A. G. McADIE. W. L. TRENHOLM. There have been 14 meetings for the presentation and discussion of papers (not including the public meeting of December 4); the average attendance has been 47. There have been 2 meetings of the Mathematical Section; average attendance 16. In the general meetings 39 communications have been presented; in the mathematical 8. Altogether 42 communications have been @ made by 29 members and candidates for membership and by 2 guests. The number of members who have participated in the dis- cussions is 38. The total number who have contributed to the scientific proceedings is 49, or 27 per cent. of the present active membership. The General Committee has held 15 meetings; average attend- ance 12, the smallest attendance at any meeting being 7 and the largest 15. G. K. GILBert, Marcus Baker, Secretaries. XXX PHILOSOPHICAL SOCIETY OF WASHINGTON. THE REPORT OF THE TREASURER. Mr. President and Gentlemen: The report which I shall presently have the honor to submit to you shows the total receipts and disbursements for the fiscal year ending with this meeting. The actual income belonging to the year 1886 was $878.00, and the expenditures for the same period were $451.50, leaving a net surplus of $426.50. The unpaid dues of former years which have been collected this year, amount to $175.00. By a resolution of the General Committee, passed May 22, 1886, the Treasurer was authorized to invest six hundred dollars of the surplus funds of the Society in six second-mortgage bonds of the Cosmos Club of this city. The present high premium on Govern- ment bonds reduces the annual interest upon them to about 2? per cent. The bonds purchased were obtained at par, and pay an interest of five per cent. per annum, the security being an extremely valuable piece of city property. The assets of the Society consist of: 2 Government bonds, $1,000 and $500, at 4 per cent., $1,500 00 1 a bond, 1,000, a Re 1,000 00 6 Cosmos Club bonds, «5 ss 600 00 Cash with Riggs & Cosi ite aa) 6 |e cwihel wii doe) ee Unpaid:dues cod cee. mad? 7S. nhs See ose PROBE cys sto gach Rach rd pputeoecins, «110 grag oi anaes elk ea Of the “unpaid dues” it is probable that a part cannot be col- lected; on the other hand, the market value of the bonds is in® excess of their face value. Volume VIII of the Bulletin was duly sent in February to all members entitled to receive it, and to the societies and scientific journals with which it is the custom of the Philosophical Society to exchange its publications. XXXI TREASURER’S REPORT. ‘vainsna4y, “SHHOLATA LYALOW "O88T ‘ST vaquasag ‘NOLDNIHSV A Soo 20 LEg'Tg 60 L89'T$ ICTs ea at i ae ate OD B sHSry YIM ooureg |) 00 OZI Zo 86 Tote rens sm s=—-o9g ‘QI [BOIIE[ ‘AIIUOTy 00: Gis = 980 -vys ‘osvysod 10j JoInsvaly, put solayze100g -19}UI $,0U 9 n- 8 VOT =--} Jo sosuodxe snoouvyjaostur 103 pred ysvo Ag 0028t:- = a » 6 O00T » cP 8g See are nae ‘048 ‘sprvo [wysod ‘srvpno11o O0209Gs==5 = Sees ‘yuoo sed F 48 QOG'TE UO —suyulid snoourjaostut 10g pred ysvo Aq ‘gt ‘00g : Spuoq UO 4sorOJUT IOJ ” ” 00 009 ==" qQnIO soulsop ‘spuoq 9g 03 pred ysvo Ag OOL08Ls = “9881 ” ” ” HOGE be a5 pee Por ea COOgE: Os 9881 i oe GI ¥8 souvpus;3e soz s0yruel pred ysvo gq ‘yz Avy || 00 Gp 277 PSST ” » ” I 7s a alga PANE Fee ulqelIng oqy COe8 Se 8881 JO sonp 10g ” ” JOTITA ‘(OA Surddvim pure ‘Surpurq ‘Sur 00 8 “““Ulja[Ng JO sayvs WIOIJ POATADI YSvd 4, “QT “00q “quyad Joy opomyoq » ppne pred ysvo Ag “GT “Ivy || ZO F8PS ~~~SSBI ‘GT ‘20q ‘Puy UO Ysvo oouL[eq of, ‘9881 ‘988T im: 18) ‘uopburysoyy fo hgars0g yoorydosonyg YF, Yn qunovnp we sainspany, 2Y.L "aq a Fig’ i; : ‘ i _ US Uva Sevita be ee. r? t aaa tg | 7 Arts: HK : ; pee ig -eegee . | 7 | 3 = iv tes were. Soa sis j | pe eis ; iS ; BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON, ANNUAL ADDRESS OF THE PRESIDENT. XXXIII . " A ‘ A -_ i" * A ‘® t oh , . iv A Med z . hes ; ¥ . h* j y I ry iA y » of i a Vee | Ne i. an wat | j ; j * Bre * . 4 i ‘ " f , } ‘ j 4 ; ord ol fF Wee ee , , nik! ad { i + 1 t + 4 Si J ANNUAL ADDRESS OF THE PRESIDENT, JOHN S. BILLINGs. Delivered December 4, 1886. SCIENTIFIC MEN AND THEIR DUTIES. Mr. Chairman and Fellow-Members of the Philosophical Society : The honor of the presidency of such a society as this—carrying with it, as it does, the duty of giving at the close of the term of office an address on some subject of general interest, has been aptly compared to the little book mentioned in the Revelations of St. John—the little book which was “sweet in the mouth but bitter in the belly.” I can only thank you for the honor, and ask your in- dulgence as to the somewhat discursive remarks which - am about to inflict upon you. ‘ There is a Spanish proverb to the effect that no man can at the same time ring the bell and walk in the procession. For a few mo- ments to-night I am to ring the bell, and being thus out of the pro- cession I can glance for a moment at that part of it which is nearest, At first sight it does not appear to be a very homogeneous or well- ordered parade, for the individual members seem to be scattering in every direction, and even sometimes to be pulling in opposite ways; yet there is, after all, a definite movement of the whole mass in the direction of what we call progress. It is not this general movement that I shall speak of, but rather of the tendencies of individuals or of certain classes; some of the molecular movements, so to speak, which are not only curious and interesting of themselves, but which have an important bearing upon the mass, and some comprehension of which is necessary to a right understanding of the present con- dition and future prospects of science in this country. The part of the procession of which I speak is made up of that body or class of men who are known to the public generally as “scientists,” “scientific men,” or “men of science.” As commonly used, all these terms have much the same significance ; but there are, nevertheless, shades of distinction between them, and in fact we need several other XXXV XXXVI PHILOSOPHICAL SOCIETY OF WASHINGTON. terms for purposes of classification of the rather heterogeneous mass to which they are applied. The word “scientist” is a coinage of the newspaper reporter, and, as ordinarily used, is very comprehensive. Webster defines a scientist as being “one learned in science, a savant ’’—that is, a wise man—and the word is often used in this sense. But the suggestion which the word conveys to my mind is rather that of one whom the public suppose to be a wise man, whether he is so or not, of one who claims to be scientific. I shall, therefore, use the term “scientist” in the broadest sense, as including scientific men, whether they claim to be such or not, and those who claim to be scientific men whether they are so or not. By a scientific man I mean a man who uses scientific method in the work to which he specially devotes himself; who possesses scientific knowledge,—not in all departments, but in certain special fields. By scientific knowledge we mean knowledge which is definite and which can be accurately expressed. It is true that this can rarely be done completely, so that each proposition shall precisely indicate its own conditions, but this is the ideal at which we aim. There is no man now living who can properly be termed a complete savant, or scientist, in Webster’s sense of the word. There are a few men who are not only thoroughly scientific in their own special departments, but are also men possessed of much knowledge upon other subjects and who habitually think scientifically upon most matters to which they give consideration ; but these men are the first to admit the incompleteness and super- ficiality of the knowledge of many subjects which they possess, and to embrace the opportunity which such a society as this affords of meeting with students of other branches, and of making that specially advantageous exchange in which each gives and receives, yet retains all that he had at first. Almost all men suppose that they think scientifically upon all subjects; but, as a matter of fact, the number of persons who are so free from personal equation due to heredity, to early associations, to emotions of various kinds, or to temporary disorder of the digestive or nervous machinery that their mental vision is at all times achro- matic and not astigmatic, is very small indeed. Every educated, healthy man possesses some scientific knowledge, and it is not possible to fix any single test or characteristic which will distinguish the scientific from the unscientific man. There are scientific tailors, bankers, and politicians, as well as physicists, ANNUAL ADDRESS OF THE PRESIDENT. XXXVII chemists, and biologists. Kant’s rule, that in each special branch of knowledge the amount of science, properly so called, is equal to the amount of mathematics it contains, corresponds to the definition of pure science as including mathematics and logic, and nothing else. It also corresponds to the distinction which most persons, consciously or unconsciously, make between the so-called physical, and the natural or biological sciences. Most of us, I presume, have for the higher mathematics, and for the astronomers and physicists who use them, that profound respect which pertains to comparative ignorance, and to a belief that capacity for the higher branches of abstract analysis is a much rarer mental quality than are those required for the average work of the naturalist. I do not, however, propose to discuss the hierarchy of the sciences; and the term science is now so generally used in the sense of knowledge, more or less accurate, of any subject, more especially in the relations of causes and effects, that we must use the word in this sense, and leave to the future the task of devising terms which will distinguish the sciences, properly so called, from those branches of study and occu- pation of which the most that can be said is that they have a scien- tific side. It isa sad thing that words should thus become polar- ized and spoiled, but there seems to be no way of preventing it. In a general way we may say that a scientific man exercises the intellectual more than the emotional faculties, and is governed by his reason rather than by his feelings. Heshould be a man of both general and special culture, who has a little accurate information on many subjects and much accurate information on some one or two subjects, and who, moreover, is aware of his own ignorance and is not ashamed to confess it. We must admit that many persons who are known as scientists do not correspond to this definition. Have you never heard, and perhaps assented to, some such statements as these: “Smith is a scientist, but he doesn’t seem to have good, common sense,” or “ he is a scientific crank ?” The unscientific mind has been defined as one which “is willing to accept and make statements of which it has no clear conceptions to begin with, and of whose truth it is not assured. It is the state of mind where opinions are given and accepted without ever being subjected to rigid tests.” Accepting this definition, and also the implied definition of a scientific mind as being the reverse of this, let us for a moment depart from the beaten track which presi- XXXVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. dential addresses usually follow, and instead of proceeding at once to eulogize the scientific mind and to recapitulate the wonderful results it has produced, let us consider the unscientific mind a little, not in a spirit of lofty condescension and. ill-disguised contempt, but sympathetically, and from the best side that we can find. As this is the kind of mind which most of us share with our neighbors, to a greater or less degree, it may be as well not to take too gloomy a view of it. In the first place, the men with unscientific minds form the immense majority of the human race. Our associations, habits, customs, laws, occupations, and pleasures are, if the main, suited to these unscientific minds; whose enjoyment of social intercourse, of the every-day occurrences of life, of fiction, of art, poetry, and the drama is, perhaps, none the less because they give and accept opinions without subjecting them to rigid tests. It is because there are a goodly number of men who do this that the sermons of clergymen, the advice of lawyers, and the pre- scriptions of physicians have a market value. This unscientific public has its uses. We can at least claim that we furnish the ma- terials for the truly scientific mind to work with and upon; it is out of this undifferentiated mass that the scientific mind supposes itself to be developed by specialization, and from it that it obtains the means of its own existence. The man with the unscientific mind, who amuses himself with business enterprises, and who does not care in the least about ohms or pangenesis, may, nevertheless, be a man who does as much good in the world, is as valuable a citizen, and as pleasant a companion as some of the men of scientific minds with whom we are acquainted. . And in this connection I venture to express my sympathy for two classes of men who have in all ages been generally condemned and scorned by others, namely, rich men and those who want to be rich. I do not know that they need the sympathy, for our wealthy citi- zens appear to support with much equanimity the disapprobation with which they are visited by lecturers and writers—a condemna- tion which seems in all ages to have been bestowed on those who have by those who have not. So far as those who actually are rich are concerned, we may, I suppose, admit that a few of them—those who furnish the money to endow universities and professorships, to build laboratories, or to furnish in other ways the means of support to scientific men—are not wholly bad. Then, also, it is not always a man’s own fault that ANNUAL ADDRESS OF THE PRESIDENT. XXXIX he is rich; even a scientist may accidentally and against his will become rich. As to those who are not rich, but who wish to be rich, whose chief desire and object is to make money, either to avoid the necessity for further labor, or to secure their wives and children from want, or for the sake of power and desire to rule, I presume it is unsafe to try to offer any apologies for their existence. But when it is claimed for any class of men, scientists or others, that they do not want these things it is well to remember the remarks made by old Sandy Mackay after he had heard a sermon on universal brotherhood: “And so the deevil’s dead. Puir auld Nickie; and himso little ap- preciated, too. Every gowk laying his sins on auld Nick’s back. But I’d no bury him until he began to smell a wee strong like. It’s a grewsome thing is premature interment.” I have tried to indicate briefly the sense in which the terms “sci- entist”’ and “scientific man” are to be used and understood, and you see it is not an easy matter. The difficulty is less as regards the term “man of science.” By this expression we mean a man who belongs to science peculiarly and especially, whose chief object in life is scientific investigation, whose thoughts and hopes and desires are mainly concentrated upon his search for new knowledge, whose thirst for fresh and accurate information is constant and insatiable. These are the men who have most advanced science, and whom we delight to honor, more especially in these later days, by glowing eulogiums of their zeal, energy, and disinterestedness. The man of science, as defined by his eulogists, is the beaw idéal of a philosopher, a man whose life is dedicated to the advancement of knowledge for its own sake, and not for the sake of money or fame, or of professional position or advancement. He undertakes scientific investigations exclusively or mainly because he loves the work itself, and not with any reference to the probable utility of the results. Such men delight in mental effort, or in the observa- tion of natural phenomena, or in experimental work, or in historical research, in giving play to their imagination, in framing hypotheses and then in endeavoring to verify or disprove them, but always the main incentive is their own personal satisfaction (with which may be mingled some desire for personal fame), and not the pleasure or the good of others. Carried to an extreme, the eulogy of such men and their work is expressed in the toast of the Mathematical Society of England: “Pure mathematics; may it never be of use to any XL PHILOSOPHICAL SOCIETY OF WASHINGTON. man!” Now, it is one thing to seek one’s own pleasure, and quite another thing to pride one’s self upon doing so. « The men who do their scientific work for the love of it do some of the best work, and, as a rule, do not pride themselves on it, or feel or express contempt for those who seek their pleasure and amusement in other direc- tions. It is only from a certain class of eulogists of pure science, so called, that we get such specimens of scientific “dudeism” as the toast just quoted, opposed to which may be cited the Arab saying that “A wise man without works is like a cloud without water.” There are other men who devote themselves to scientific work, but who prefer to seek information that may be useful; who try to advance our knowledge of Nature’s laws in order that man may know how to adapt himself and his surroundings to those laws, and thus be healthier and happier. They make investigations, like the men of pure science—investigations in which they may or may not take pleasure, but which they make, even if tedious and disagree- able, for the sake of solving some problem of practical importance. These are the men who receive from the public the most honor, for it is seen that their work benefits others. After all, this is not peculiar to the votaries of science. In all countries and all times, and among all sorts and conditions of men, it has always been agreed that the best life, that which most deserves praise, is that which is devoted to the helping others, which is unselfish, not stained by envy or jealousy, and which has as its main pleasure and spring of action the desire of making other lives more pleasant, of bringing light into the dark places, of helping humanity. But, on the other hand, the man who makes a profession of doing this, and who makes a living by so doing, the professional philan- thropist, whether he be scientist or emotionalist, is by no means to be judged by his own assertions. Some wise German long ago re- marked that “Esel singen schlecht, weil sie zu hoch anstimmen” —that is, “asses sing badly because they pitch their voices too high,” and it is a criticism which it is well to bear in mind. In one of the sermons of Kin O* the preacher tells the story of a powerful clam who laughed at the fears of other fish, saying that when he shut himself up he felt no anxiety ; but on trying this method on one occasion when he again opened his shell he found himself in a fishmonger’s shop. And to rely on one’s own talents, * Cornhill Magazine, August, 1869, p. 196. ANNUAL ADDRESS OF THE PRESIDENT. xXLI on the services one may have rendered, on cleverness, judgments strength, or official position, and to feel secure in these, is to court the fate of the clam. There are not very many men of science, and there are no satis- factory means of increasing the number; it is just as useless to ex- hort men to love science, or to sneer at them because they do not, as it is to advise them to be six feet three inches high or to condemn a man because his hair is not red. While the ideal man of science must have a “clear, cold, keen intellect, as inevitable and as merciless in its conclusions as a logic engine,” it would seem that, in the opinion of some, his greatness and superiority consists not so much in the amount of knowledge he possesses, or in what he does with it, as in the intensity and purity of his desire for knowledge. This so-called thirst for knowledge must be closely analogous to an instinctive desire for exercise of an organ or faculty, such as that which leads a rat to gnaw, or a man of fine physique to delight in exercise. Such instincts should not be neglected. If the rat does not gnaw, his teeth will become inconvenient or injurious to himself, but it is not clear that he deserves any special eulogium merely because he gnaws. It will be observed that the definition of a scientific man or man of science, says nothing about his manners or morals. We may infer that-a man devoted to science would have neither time nor inclination for dissipation or vice; that he would be virtuous either because of being passionless or because of his clear foresight of the consequences of yielding to temptation. My own experience, however, would indicate that either this inference is not correct or that some supposed scientific men have been wrongly classified as such. How far the possession of a scien- tific mind and of scientific knowledge compensates, or atones for, ill-breeding or immorality, for surliness, vanity, and petty jealousy, for neglect of wife or children, for uncleanliness, physical and mental, is a question which can only be answered in each individual case; but the mere fact that a man desires knowledge for its own sake appears to me to have little to do with such questions. I would prefer to know whether the man’s knowledge and work is of any use to his fellow-men, whether he is the cause of some happiness in others which would not exist without him. And it may be noted that while utility is of small account in the eyes of some eulogist, 37 XLII PHILOSOPHICAL SOCIETY OF WASHINGTON. of the man of science they almost invariably base their claims for his honor and support upon his usefulness. : The precise limit beyond which a scientist should not make money has not yet been precisely determined, but in this vicinity there are some reasons for thinking that the maximum limit is about $5,000 per annum. If there are any members of the Philo- sophical Society of Washington who are making more than this, or who, as the result of careful and scientific introspection, discover in themselves the dawning of a desire to make more than this, they may console themselves with the reflection that the precise ethics and etiquette which should govern their action under such painful circumstances have not yet been formulated. The more they demonstrate their indifference to mere pecuniary considerations the more creditable it is to them; so much all are agreed upon; but this is nothing new, nor is it specially applicable to scientists. Yet while each may and must settle such questions as regards himself for himself, let him be very cautious and chary about trying to settle them for other people. Denunciations of other men engaged in scientific pursuits on the ground that their motives are not the proper ones are often based on insufficient or inaccurate knowledge, and seldom, I think, do good. This is a country and an age of hurry, and there seems to be a desire to rush scientific work as well as other things. One might suppose, from some of the literature on the subject, that the great object is to make discoveries as fast as possible; to get all the math- ematical problems worked out; all the chemical combinations made; all the insects and plants properly labeled; all the bones and mus- cles of every animal figured and described. From the point of view of the man of science there does not seem to be occasion for such haste. Suppose that every living thing were known, figured, and described. Would the naturalist be any happier? Those who wish to make use of the results of scientific investigation of course desire to hasten the work, and when they furnish the means we can- not object to their urgency. Moreover, there is certainly no occa- sion to fear that our stock of that peculiar form of bliss known as ignorance will be soon materially diminished. From my individual point of view, one of the prominent features _ in the scientific procession is that part of it which is connected with Government work. Our Society brings together a large number of scientific men connected with the various Departments; some of ANNUAL ADDRESS OF THE PRESIDENT. XLIII them original investigators; most of them men whose chief, though not only, pleasure is study. A few of them have important administrative duties, and are brought into close relations with the heads of Departments and with Congress. Upon men in such posi- tions a double demand is made, and they are subject to criticism from two very different standpoints. On the one hand are the sci- entists, calling for investigations which shall increase knowledge without special reference to utility, and sometimes asking that em- ployment be given to a particular scientist on the ground that the work to which he wishes to devote himself is of no known use, and therefore will not support him. On the other hand is the demand from the business men’s point of view—that they shall show prac- tical results; that in demands for appropriations from the public funds they shall demonstrate that the use to be made of such appro- priations is for the public good, and that their accounts shall show that the money has been properly expended—“ properly,’ not merely in the sense of usefully, but also in the legal sense—in the sense which was meant by Congress in granting the funds. Nay, more, they must consider not only the intentions of Congress but the opinions of the accounting officers of the Treasury, the comp- troller and auditor, and their clerks, and not rely solely on their own interpretation of the statutes, if they would work to the best advantage, and not have life made a perpetual burden and vexation of spirit. There is a tendency on the part of business men and lawyers to the belief that scientific men are not good organizers or administra- tors, and should be kept in leading strings; that it is unwise to trust them with the expenditure of, or the accounting for, money, and that the precise direction in which they are to investigate should be pointed out to them. In other words, that they should be made problem-solving machines as far as possible. When we reflect on the number of persons who, like Mark Twain’s cat, feel that they are “nearly lightning on superintending;” on the desire for power and authority, which is almost universal, the ten- dency to this opinion is not to be wondered at. Moreover, as re- gards the man of science, there is some reason for it in the very terms by which he is defined, the characteristics for which he is chiefly eulogized. The typical man of science is, in fact, in many cases an abnor- mity, just as a great poet, a great painter, or a great musician is XLIV PHILOSOPHICAL SOCIETY OF WASHINGTON. apt to be, and this not only in an unusual development of one part of the brain, but in an inferior development in othérs. True, there are exceptions to this rule—great and illustrious exceptions; but I think we must admit that the man of science often lacks tact, and is indifferent to and careless about matters which do not concern his special work, and especially about matters of accounts and pecuniary details. Ifsuch a man is at the head of a bureau, whose work requires many subordinates and the disbursement of large sums of money, he may consider the business management of his office as a nuisance, and delegate as much of it as possible to some subordinate official, who, after a time, becomes the real head and director of the bureau. Evil results have, however, been very-rare, and the recognition of the possibility of their occurrence is by no means an admission that they are a necessity, and still less of the proposition that administrative officers should not be scientific men. I feel very sure that there are always available scientific men, thoroughly well informed in their several departments, who are also thoroughly good business men, and are as well qualified for admin- istrative work as any. When such men are really wanted they can always be found, and, as a matter of fact, a goodly number of them have been found, and are now in the Government service. The head of a bureau has great responsibilities; and while his position is, in many respects, a desirable one, it would not be eagerly sought for by most scientific men if its duties were fully understood. In the first place the bureau chief must give up a great part of his time to routine hack work. During his business, or office, hours he can do little else than this routine work, partly because of its amount, and partly because of the frequent interruptions to which he is subjected. His visitors are of all kinds and come from all sorts of motives—some to pass away half an hour, some to get infor- mation, some seeking office. It will not work well if he takes the ground that his time is too important to be wasted on casual callers and refers them to some assistant. In the second place he must, to a great extent at least, give up the pleasure of personal investigation of questions that specially interest him, and turn them over to others. It rarely happens that he can earry out his own plans in his own way, and perhaps it is well that this should be the case. The general character of his work is usually determined for him either by his predecessors, or by Congress, or by the general consensus of opinion of scientific men interested in the ANNUAL ADDRESS OF THE PRESIDENT. XLV particular subject or subjects to which it relates. This last has very properly much weight; in fact, it has much more weight than one might suppose, if he judged from some criticisms made upon the work of some of our bureaus whose work is more or less scientific. In these criticisms it is urged that the work has not been properly planned and correlated; that it should not be left within the power of one man to say what should be done; that the plans for work should be prepared by disinterested scientific men—as, for instance, by a committee of the National Academy—and that the function of the bureau official should be executive only. I have seen a good deal of this kind of literature within the last ten or twelve years, and some of the authors of it are very distin- guished men in scientific work; yet I venture to question the wis- dom of such suggestions. As a rule, the plans for any extended scientific work to be undertaken by a Government department are the result of very extended consultations with specialists, and meet with the approval of the majority of them. Were it otherwise the difficulties in obtaining regular annual appropriations for such work would be great and cumulative, for in a short time the disapproval of the majority of the scientific public would make itself felt in Congress. It is true that the vis inertia of an established bureau is very great. The heads of Departments change with each new administration, but the heads of bureaus remain; and if an unfit man succeeds in obtaining one of these positions, it is a matter of great difficulty to displace him; but it seems to me to be wiser to direct the main effort to getting right men in right places rather than to attempt to elaborate a system which shall give good results with inferior men as the executive agents, which attempt is a waste of energy. You are all familiar with the results of the inquiry which has been made by a Congressional committee into the organization and work of certain bureaus which are especially connected with scien- tific interests, and with the different opinions which this inquiry has brought out from scientific men. I think that the conclusion of the majority of the committee, that the work is, on the whole, being well done, and that the people are getting the worth of their money, is generally assented to. True, some mistakes have ‘been made, some force has been wasted, some officials have not given satisfac- tion; but is it probable that any other system would give so much better results that it is wise to run the risks of change? XLVI PHILOSOPHICAL SOCIETY OF WASHINGTON. This question brings us to the only definite proposition which has been made in this direction, namely, the proposed Department of Science, to which all the bureaus whose work is mainly scientific, such as the Coast Survey, the Geological Survey, the Signal Service, the Naval Observatory, ete., shall be transferred. The arguments in favor of this are familiar to you, and, as re- gards one or two of the bureaus, it is probable that the proposed change would effect an improvement; but as to the desirability of centralization and consolidation of scientific interests and scientific work into one department under a single head, I confess that I have serious doubts. One of the strongest arguments in favor of such consolidation that I have seen is the address of the late president of the Chemical Society of Washington, Professor Clarke, “On the Re- lations of the Government to Chemistry,” delivered about a year ago. Professor Clarke advises the creation of a large, completely- equipped laboratory, planned by chemists and managed by chemists, in which all the chemical researches required by any department of the Government shall be made, and the abandonment of individual laboratories in the several bureaus on the ground that these last are small, imperfectly equipped, and not properly specialized ; that each chemist in them has too broad a range of duty and receives too small a salary to command the best professional ability. He would have a national laboratory, in which one specialist shall deal only with metals, another with food products, a third with drugs, ete., while over the whole, directing and correlating their work, shall preside the ideal chemist, the all-round man, recognized as the leader of the chemists of the United States. And so should the country get better and cheaper results. It is an enticing plan and one which might be extended to many other fields of work. Grant- ing the premises that we shall have the best possible equipment, with the best possible man at the head of it, and a sufficient corps of trained specialists, each of whom will contentedly do his own work as directed and be satisfied, so that there shall be no jealousies, or strikes, or boycotting, and we have made a long stride toward Utopia. But before we centralize in this way we must settle the question of classification. Just as in arranging a large library there are many books which belong in several different sections, so it is in applied science. Is it certain that the examination of food products or of drugs should be made under the direction of the national ANNUAL ADDRESS OF THE PRESIDENT. XLVII chemist rather than under that of the Departments which are most interested in the composition and quality of these articles? This does not seem to me to be a self-evident proposition by any means. The opinion of a scientific man as to whether the Government should or should not undertake to carry out any particular branch of scientific research and publish the results, whether it should attempt to do such work through officers of the Army and Navy, or more or less exclusively through persons specially employed for the pur- pose, whether the scientific work shall be done under the direction of those who wish to use, and care only for, the practical results, or whether the scientific man shall himself be the administrative head and direct the manner in which his results.shall be applied; the opinion of a scientific man on such points, I say, will differ accord- ing to the part he expects or desires to take in the work, according to the nature of the work, according to whether he is an Army or Navy officer or not, according to whether he takes more pleasure in scientific investigations than in administrative prob- lems, and so forth. It is necessary, therefore, to apply a correction for personal equa- tion to each individual set of opinions before its true weight and value ean be estimated, and, unfortunately, no general formula for this purpose has yet been worked out. I can only indicate my own opinions, which are those of an Army officer, who has all he wants to do, who does not covet any of his neighbors’ work or goods, and who does not care to have any more masters than those whom he is at present trying to serve. You see that I give you some of the data for the formula by which you are to correct my statements, but this is all I can do. I am not inclined at present to urge the creation of a department of science as an independent department of the Government having at its head a Cabinet officer. Whether such an organization may become expedient in the future seems to me doubtful; but at all events I think the time has not yet come for it. I do not believe that Government should undertake scientific work merely or mainly because it is scientific, or because some useful results may possibly be obtained from it. It should do, or cause to be done, such scientific work as is needful for its own in- formation and guidance when such work cannot be done, or cannot be done so cheaply or conveniently, by private enterprise. Some kinds of work it can best have done by private contract, and not by XLVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. officials; others, by its own officers. To this last class belong those branches of scientific investigation, or the means for promoting them, which require long-continued labor and expenditure on a uniform plan—such as the work of the Government Observatory, of the Government surveys, of the collection of the statistics which are so much needed for legislative guidance, and in which we are at present so deficient, the formation of museums and libraries, and so forth. Considering the plans and operations of these Government insti- tutions from the point of view of the scientific public, it is highly desirable that they should contribute to the advancement of abstract science, as well as to fhe special practical ends for which they have been instituted; but from the point of view of the legislator, who has the responsibility of granting the funds for their support, the practical results should receive the chief consideration, and there- fore they should be the chief consideration on the part of those who are to administer these trusts. It must be borne in mind that while the average legislator is,in many cases, not qualified to judge a priori as to what practical results may be expected from a given plan for scientific work, he is, nevertheless, the court which is to decide the question according to the best evidence which he can get, or, rather, which is brought before him, and it is no unimportant part of the duty of those who are experts in these matters to fur- nish such evidence. But in saying that practical results should be the chief considera- tion of the Government and of its legislative and administrative agents it is not meant that these should be the only considerations. In the carrying out of any extensive piece of work which involves the collection of data, experimental inquiry, or the application of scientific results under new conditions there is more or less oppor- tunity to increase knowledge at the same time and with compara- tively little increased cost. Such opportunity should be taken ad- vantage of, and is also a proper subsidiary reason for adopting one plan of work in preference to another, or for selecting for appoint- ment persons qualified not only to do the particular work which is the main object, but also for other allied work of a more purely scientific character. On the same principle it seems to me proper and expedient that when permanent Government employees have at times not enough to do in their own departments, and can be usefully employed in ANNUAL ADDRESS OF THE PRESIDENT. XLIX scientific work, it is quite legitimate and proper to thus make use of them. For example, it is desirable that this country should have such an organization of its Army and Navy as will permit of rapid expansion when the necessity arises, and this requires that more officers shall be educated and kept in the service than are needed for military and naval duty in time of peace. It has been the policy of the Government to employ some of these officers in work connected with other departments, and especially in work which requires such special training, scientific or administrative, or both, as such officers possess. ‘To this objections are raised, which may be summed up as follows: First, that such officers ought not to be given positions which _ would otherwise be filled by civilian scientists, because these places are more needed by the civilians as a means of earning subsistence, and because it tends to increase the competition for places and to ’ lower salaries. Put in other words, the argument is that it is in- jurious to the interests of scientific men, taken as a body, that the Government should employ in investigations or work requiring special knowledge and skill men who have been educated and trained at its expense, and who are permanently employed and paid by it. This is analogous to the trades union and the anti-convict labor platforms. The second objection is that Army and Navy officers do not, asa rule, possess the scientific and technical knowledge to properly per- form duties lying outside of the sphere of the work for which they have been educated, and that they employ as subordinates really skilled scientific men, who make the plans and do most of the work, but do not receive proper credit for it. The reply to this is that it is a question of fact in each particular case, and that if the officer is able to select and employ good men to prepare the plans and to do the work, this in itself is a very good reason for giving him the duty of such selection and employment. A third objection is that when an officer of the Army or Navy is detailed for scientific or other special work the interests of this work and of the public are too often made subordinate to the interests of the naval or military service, more especially in the matter of change of station. For example, civil engineers object to the policy of placing river and harbor improvements in the hands of Army engineers, because one of the objects kept in view by the War Department in making details for this purpose is to vary the L PHILOSOPHICAL SOCIETY OF WASHINGTON. duty of the individual officer from time to time so as to give him a wider experience. Hence it may happen that an officer placed on duty in connection with the improvement of certain harbors on the Great Lakes shall, after three or four years, and just as he has gained sufficient experience of the peculiarities of lake work to make his supervision there peculiarly valuable, be transferred to work on the - improvement of the Lower Mississippi with which he may be quite unfamiliar. In like manner Professor Clarke objects to having a labora- tory connected with the medical department of the Navy on the ground that the officer in charge is changed every three years; consequently science suffers in order that naval routine may be pre- served. There is force in this class of objections, but the moral I should draw from them is, not that Army and Navy officers should not be allowed to do work outside their own departments or in science, but that when they are put upon such duty, the ordinary routine of change of station every three or four years should not be enforced upon them without careful consideration of the circumstances of the case, and satisfactory evidence that the work on which they are en- gaged will not suffer by the change. And, as a matter of fact, I believe this has been the policy pursued, and instances could be given where an officer has been kept twenty years at one station for this very reason. I pass over a number of objections that I have heard made to the employment of Army and Navy officers as administrators, on the ground that they are too “ bumptious,” or “domineering,” or “super- cilious,” or “finicky,” because every one knows what these mean and their force. An Army officer is not necessarily a polished gentleman ; neither is a civilian; and a good organizer and administrator, whether officer or civilian, will at times, and especially to some people, appear arbitrary and dictatorial. There is another objection to special details of Army or Navy officers for scientific duties which comes not so much from outside persons as from the War Department and the officers themselves, and it is this: Among such officers there are always a certain num- ber who not only prefer special details to routine duty, but who actively seek for such details, who are perpetual»eandidates for them. The proportion of men whose ideas as to their own scientific ac- ANNUAL ADDRESS OF THE PRESIDENT. Lt quirements, merits, and claims to attention are excessive as com- pared with the ideas of their acquaintances on the same points is not greater in the Army than elsewhere, but when an Army officer is afflicted in this way the attack is sometimes very severe, and the so-called influence which he brings to bear may cause a good deal of annoyance to the Department, even if it be not sufficient to obtain his ends. I have heard officers of high rank, in a fit of impatience under such circumstances, express a most hearty and emphatic wish that no special details were possible, so that lobbying for them should be useless. This, however, seems to me to be too heroic a remedy for the disease, which, after all, only produces comparatively trifling irritation and discomfort. The same evil exists, to a much greater extent, in the civil branches of the Government. Few persons can fully appreciate the loss of time, the worry, and the annoyance to which the respon- sible heads of some of our bureaus for scientific work are subjected through the desire of people for official position and for mainte- nance by the Government. They have to stand always at the bat and protect their wickets from the balls which are bowled at them in every direction, even from behind by some of their own subor- dinates. _Itis true that a great majority of the balls go wide and cause little trouble, and a majority of the bowlers soon get tired and leave the field, but there are generally a few persistent ones who gradually acquire no small degree of skill in discovering the weak or unguarded points, and succeed in making things lively for a time. Considered from the point of view of the public interests, such men are useful, for although they cause some loss of valuable time, and occasionally do a little damage by promoting hostile legislation, yet their criticisms are often worth taking into account; they tend to prevent the machine from getting into a rut, and they promote activity and attention to business on the part of administrative chiefs. It is a saying among dog fanciers that a few fleas on a dog are good for him rather than otherwise, as they compel him to take some exercise under any circumstances. At all events I think it very doubtful whether the jealousies and desire for position for one’s self or one’s friends which exist under present circumstances would be materially diminished under any other form of organization, even under a department of science. Some conflict of interests now exists it is true; some work is dupli- Lil PHILOSOPHICAL SOCIETY OF WASHINGTON. cated ; but neither the conflict nor the duplication are necessarily wholly evil in themselves, nor in so far as they are evil are they necessary parts of the present system. This system is of the nature of a growth; it is organic and not a mere pudding-stone aggrega- tion of heterogeneous materials, and the wise course is to correct improper bendings and twistings gradually, prune judiciously, and go slow in trying to secure radical changes lest death or permanent deformity result. Tt will be seen that in what I have said I have not attempted to eulogize science or scientists in the abstract. I should be very sorry, however, to have given any one the impression that I think they should not be eulogized. Having read a number of eloquent tributes to their importance by way of inducing a proper frame of mind in which to prepare this address, it is possible that I overdid it a little, and was in a sort of reaction stage when I began to write. But the more I have thought on the subject, and the more care- fully I have sought to analyze the motives and character of those of my acquaintances who are either engaged in scientific work or who wish to be considered as so doing, and to compare them with those who have no pretensions to science, and who make none, the more I have been convinced that upon the whole the eulogium is the proper thing to give, and that it is not wise to be critical as to the true inwardness of all that we see or hear. At least nine-tenths of the praises which have been heaped upon scientific men as a body are thoroughly well deserved. Among them are to be found a very large proportion of true gentlemen, larger, I think, than is to be found in any other class of men—men char- acterized by modesty, unselfishness, scrupulous honesty, and truth- fulness, and by the full performance of their family and social duties. Even their foibles may be likable. A little vanity or thirst for publicity, zeal in claiming priority of discovery, or undue wrath over the other scientist’s theory, does not and should not detract from the esteem in which we hold them. A very good way of viewing characteristics which we do not like is to bear in mind that different parts of the brain have different functions; that all of them cannot act at once, and that their tendencies are sometimes contradictory. There are times when a scientific man does not think scientifically, when he does not want to so think, and possibly when it is best that he should not so think. There is wisdom in Sam. Lawson’s remark ANNUAL ADDRESS OF THE PRESIDENT. LIII that “ Folks that are always telling you what they don’t believe are sort o’ stringy and dry. There ain’t no ’sorption got out o’ not be- lieving nothing.” At one time the emotional, at another the intel- lectual, side of the scientific man has the ascendency, and one must appeal from one state to the other. Were scientific thinking rigor- ously carried out to practical results in every-day life there would be some very remarkable social changes, and perhaps some very disagreeable ones. That scientific pursuits give great pleasure without reference to their utility, or to the fame or profit to be derived from them; that they tend to make a man good company to himself and to bring him into pleasant associations is certain; and that a man’s own pleasure and happiness are things to be sought for in his work and companionship is also certain. If in this address I have ventured to hint that this may not be the only, nor even the most important, object in life, that one may be a scientific man, or even a man of science, and yet not be worthy of special reverence; because he may be at the same time an intensely selfish man, and even a vicious man, I hope that it is clearly understood that it is with no inten- tion of depreciating the glory of science or the honor which is due to the large number of scientific gentlemen whom I see around me. A scientific gentleman—all praise to him who merits this title— it is the blue ribbon of our day. We live in a fortunate time and place; in the early manhood of a mighty nation, and in its capital city, which every year makes more beautiful, and richer in the treasures of science, literature, and art which all the keels of the sea and the iron roads of the land are bringing to it. Life implies death; growth presages decay ; but we have good reasons for hoping that for our country and our people the evil days are yet far off. Yet we may not rest and eat lotus; we may not devote our lives to our own pleasure, even though it be pleasure derived from scientific investigation. No man lives for himself alone; the scientific man should do so least of all. There never was a time when the world had more need of him, and there never was a time when more care was needful lest his torch should prove a firebrand and destroy more than it illuminates. The old creeds are quivering; shifting; changing like the colored flames on the surface of the Bessemer crucible. They are being analyzed, and accounted for, and toned down, and explained, until many are doubting whether there is any solid substratum beneath ; LIV PHILOSOPHICAL SOCIETY OF WASHINGTON. but the instinct which gave those creeds their influence is un- changed. : The religions and philosophies of the Orient seem to have little in common with modern science. The sage of the east did not try to climb the ladder of knowledge step by step. He sought a wisdom which he supposed far superior to all knowledge of earthly phenomena obtainable through the senses. The man of science of the west seeks knowledge by gradual accumulation, striving by comparison and experiment to eliminate the errors of individual observations, and doubting the possibility of attain- ing wisdom in any other way. The knowledge which he has, or seeks, is knowledge which may be acquired partly by individual effort and partly by co-operation, which requires material resources for its development, the search for which may be organized and pursued through the help of others, which is analogous in some respects to property which may be used for power or pleasure. The theologian and the poet claim that there is a wisdom which is not acquired but attained to, which cannot be communicated or received at pleasure, which comes in a way vaguely expressed by the words intuition or inspiration, which acts through and upon the emotional rather than the intellectual faculties, and which, thus acting, is sometimes of irresistible power in exciting and ili a the actions of individuals and of communities. The answer of the modern biologist to the old Hebrew question, viz. “ Why are children born with their hands clenched while men die with their hands wide open?” would not in the least resemble that given by the Rabbis, yet this last it is well that the scientist should also remember: ‘“ Because on entering the world men would grasp everything, but on leaving it all slips away.” There exist in men certain mental phenomena, the study of which is included in what is known as ethics, and which are usually assumed to depend upon what is called moral law. Whether there is such a law and whether, if it exists, it can be logically deduced from observed facts in nature or is only known as a special revelation, are questions upon which scientific men in their present stage of development are not agreed. There is not yet any satisfactory scientific basis for — what is recognized as sound ethics and morality throughout the civil- ized world; these rest upon another foundation. This procession, bearing its lights of all kinds, smoky torches, clear-burning lamps, farthing rush-lights, and sputtering brimstone ANNUAL ADDRESS OF THE PRESIDENT. LV matches, passes through the few centuries of which we have a record, illuminating an area which varies, but which has been grow- ing steadily larger. The individual members of the procession come from, and pass into, shadow and darkness, but the light of the stream remains. Yet it does not seem so much darkness, an infinite night, whence we come and whither we go, as a fog which at a little dis- tance obscures or hides all things, but which, nevertheless, gives the impression that there is light beyond and above it. In this fog we are living and groping, stumbling down blind alleys, only to find that there is no thoroughfare, getting lost and circling about on our own tracks as on a jumbie prairie; but slowly and irregularly we do seem to be getting on, and to be establishing some points in the survey of the continent of our own ignorance, In some directions the man of science claims to lead the way; in others the artist, the poet, the devotee. Far reaching as the specu- lations of the man of science may be, ranging from the constitution and nature of a universal protyle, through the building of a universe to its resolution again into primal matter or modes of motion, he ean frame no hypothesis which shall explain consciousness, nor has he any data for a formula which shall tell what becomes of the in- dividual when he disappears in the all-surrounding mist. Does he go on seeking and learning in other ways or other worlds? The great mass of mankind think that they have some information bear- ing on these questions; but, if so, it is a part of the wisdom of the Orient, and not of the physical or natural science of the Occident. Whether after death there shall come increase of knowledge, with increase of desires and of means of satisfying them, or whether there shall be freedom from all desire, and an end of coming and going, we do not know; nor is there any reason to suppose that it is a part of the plan of the universe that we should know. We do know that the great majority of men think that there are such things as right and duty—God and a future life—and that to each man there comes the opportunity of doing something which he and others recognize to be his duty. The scientific explanation of a part of the process by which this has been brought about, as by natural selection, heredity, education, progressive changes in this or that particular mass of brain matter, has not much bearing on the practical ques- tion of “ What to do about it?” But it does, nevertheless, indicate that it is not a characteristic to be denounced, or opposed, or neg- lected, since, even in the “struggle-for-existence” theory, it has LVI PHILOSOPHICAL SOCIETY OF WASHINGTON. been, and still is, of immense importance in human social develop- ment. - “Four men,” says the Talmud, “entered Paradise. One beheld and died. One beheld and lost his senses. One destroyed the young plants. One only entered in peace and came out in peace.” Many are the mystic and cabalistic interpretations which have been given of this saying; and if for ‘“‘ Paradise” we read the “ world of knowl- edge” each of you can no doubt best interpret the parable for him- self. Speaking to a body of scientific men, each of whom has, I hope, also certain unscientific beliefs, desires, hopes, and longings, I will only say: “Be strong and of a good courage.” As scientific men, let us try to increase and diffuse knowledge; as men and citi- zens, let us try to be useful; and, in each capacity, let us do the work that comes to us honestly and thoroughly, and fear not the unknown future. ; When we examine that wonderful series of wave marks which we call the spectrum we find, as we go downwards, that the vibrations become slower, the dark bands wider, until at last we reach a point where there seems to be no more movement; the blackness is con- tinuous, the ray seems dead. Yet within this year Langley has found that a very long way lower down the pulsations again appear, and form, as it were, another spectrum; they never really ceased, but only changed in rhythm, requiring new apparatus or new senses to appreciate them. And it may well be that our human life is only a kind of lower spectrum, and that, beyond and above the broad black band which we call death, there are other modes of impulses—another spectrum—which registers the ceaseless beats of waves from the great central fountain of force, the heart of the universe, in modes of existence of which we can but dimly dream. BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. GENERAL MEETING. (1) PE BA ne ides : BULLETIN OF THE GENERAL MEETING. 279TH MEETING. JANUARY 16, 1886. President BrLur1nas in the Chair. | Thirty-two members and guests present. Announcement was made of the election to membership of Messrs. BENJAMIN PicKMAN MANN and Cuartes Coorer Norv. The following report of the Auditing Committee was presented by its chairman, Mr. TonER: DECEMBER 24, 1885. The undersigned, a committee appointed at the annual meeting of the Philosophical Society of Washington, December 19, 1885, for the purpose of auditing the accounts of the Treasurer, beg leave to report as follows: We have examined the statement of receipts, including annual dues, sale of Bulletin, and interest on bonds, and find the same to be correct as stated. We have examined the statement of disbursements, and com-' pared the same with the vouchers, and find them to agree. We have examined the returned checks and the bank account with Riggs & Co., and find the balance, $484.02, to agree with the statements in the Treasurer’s report. We have examined the U.S. bonds belonging to the Society, and find them to be in amount and character as represented in the Treasurer’s report, aggregating $2,500. J. M. Toner, O. T. Mason, T. C. MENDENHALL, Committee. (3) 4 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. J. S. DILLER communicated NOTES ON THE GEOLOGY OF NORTHERN CALIFORNIA. ) [ Abstract. ] Under the direction of Capt. Dutton I have spent the last three summers studying the geology of northern California and the ad- jacent portion of Oregon. The conclusions of a general nature referring to that region may be briefly summarized as follows: In the northern end of the Sierra Nevada and the central por- tion of the Coast range, among the highly plicated, more or less metamorphosed strata which are older than those of the Chico group, there appears to be but one horizon of limestone, and that is of Car- boniferous age. The northern end of the Sierra Nevada is made up of three tilted orographic blocks which are separated from each other by great faults. The westernmost of these blocks stretching far to the southeast appears to form the greater portion of the range. As in the Great Basin region the depressed side of each block was occupied by a body of water of considerable size. The deposits formed in these lakes gave rise to the fertile soils of American and Indian valleys. The plication of the strata in the Sierra Nevada range took place, at least in great part, about the close of the Jurassic or beginning of the Cretaceous period, but the faulting which really gave birth to the Sierra as a separate and distinct range by differentiating it from the great platform stretching eastward into the Great Basin region, did not take place until towards the close of the Tertiary or the beginning of the Quaternary. Although the faulting may have commenced earlier, the greater portion of the displacement has taken place since the deposition of a large part of the auriferous gravels and the beginning of the great volcanic outbursts in the vicinity of Lassen’s Peak. If we may accept numerous small earthquake shocks as evidence, the faulting still continues. The distribution of the rocks of the Chico group indicates that the western coast of the continent at that time lay along the western base of the Sierra extending around the northern end of the range in the vicinity of Lassen’s Peak and stretching far northeasterly into Oregon. Off the coast lay a large island which now forms & GENERAL MEETING. 5 northwestern California and the adjacent portion of Oregon. This island extended as far southeast as the Pit river region where it was separated from the main land by a wide strait. Ali of the ridges developed out of the Cretacean island belong to the Coast range. The volcanic ridge of Lassen’s Peak lies between the northern end of the Sierra Nevada and the Coast range. The great volcanic field of Oregon and Washington Territory, to which Lassen’s Peak and the Cascade range belong, appears in a general way to be out- lined by the depression between the Cretacean island and the main land. A general account of the facts from which these conclusions are drawn will appear in Bulletin of the U. S. Geological Sur- vey No. 33. Mr. I. C. Russewu read a supplementary paper entitled NOTES ON THE FAULTS OF THE GREAT BASIN AND OF THE EASTERN BASE OF THE SIERRA NEVADA. [Abstract. ] The structure of the Great Basin was systematically studied by the geologists of the Fortieth Parallel Exploration, and subsequently by G. K. Gilbert and J. W. Powell. The results of these investiga- tions, so far as they relate to the faults of the region, are indicated in the bibliographic list which follows. The studies here referred to led to the recognition of a type of mountain structure named the “Great Basin system,’ which has been found to prevail over large portions of the United States west of the Rocky Mountains. A typical mountain of this system is a long, narrow orographic block, upraised along one edge, 7. e. a mono- clinal ridge. A mountain range having this structure usually presents an abrupt scarp, formed of the edges of broken strata, on ‘the side bordered by the fault, and slopes much more gently in the opposite direction. Mountain ranges of this character occupy the greater part of the area of interior drainage, known as the Great Basin, and at times overlap its borders. An older structure in which corrugation plays an important part has been recognized by several geologists in the desert ranges of Nevada and Utah, but these disturbances were produced previous to the faulting which gave origin to the present topographic relief. 6 PHILOSOPHICAL SOCIETY OF WASHINGTON. The writer has observed Great Basin structure to extend through- out Western Utah, Northern Nevada, and into’ Oregon as far as Malheur Lake. On the west side of the Great Basin, at the imme- diate base of the Sierra Nevada, there is an immense compound displacement that can be followed all the way from Honey Lake on the north to beyond Owen’s Lake on the south, a distance of over 390 miles. Along many of the faults composing this belt the records of a post-Quaternary movement may be clearly recognized. Fault scarps produced by recent movement have been observed in Eagle and Carson Valleys, south of Carson City, in Bridgeport Valley, and on the west side of Mono Lake. The earthquake in Owen’s Valley in 1872, was caused by a movement along one of the faults of this series. The eastern face of the Sierra Nevada is extremely abrupt and its western slope is gentle. Corrugations of older date than the faults which determine the present relief of the mountains may be observed at many localities. It thus agrees in its general features with many of the Basin ranges. The Sierra Nevada is essentially monoclinal in structure, but is traversed from north to south by faults which divide it into separate ranges, as may be seen in the neighborhood of Lake Tahoe and in the elevated region west of Mono Lake. The Great Basin structure here extends beyond the borders of the area of interior drainage, and is probably limited on the west by the great valley of California. How far north of Lake . Tahoe the secondary faults that divide the mountain mass may be traced is unknown, but they can certainly be followed to where the Central Pacific railroad crosses the mountains. The following list indicates where observations on the faults of the Great Basin system may be found: Clarence King: Reports of the Fortieth Parallel Exploration. Vol. I, 1878, pp. 735, 744-746; Vol. III, 1870, p. 451. J. D. Whitney: The Owens Valley earthquake. Overland Monthly, Aug. and Sept., 1872. Joseph Le Conte: On the Structure and Origin of Mountains, with special reference to recent objections to the “Contraction Theory.” American Journal of Science, Vol. XVI, 1878, pp. 95112. ig : A theory of the formation of the great features of the earth’s crust. American Journal of Science, Vol. IV, 1872, pp. 345-355, 460-472. G. K. Gilbert: J. W. Powell: C. E. Dutton: I. C. Russell: GENERAL MEETING. 7 Progress report upon Geographical and Geological Explorations and Surveys West of the 100th Meridian, in 1872. Washington, 1874. p. 50. Report upon Geographical and Geological Explo- rations and Surveys west of the 100th Meri- dian. Washington, 1875. Vol. III, Geology, pp. 21-42. Contributions to the history of Lake Bonneville. In Second Annual Report of the U.S. Geo- logical Survey. Washington, 1882. pp. 192 —200. A theory of the earthquakes of the Great Basin with a practical application. American Journal of Science, Vol. XX VII, 1884, pp. 49-53. Basin Range System. See Report on Lands of the Arid Region of the United States. Washington, 1879. pp. 94-95. Basin Range Province. See Report on the Geology of the eastern portion of the Uinta Mountains. Washington, 1876. pp. 6-7, 23- 25. Geology of the High Plateaus of Utah. Washing- ton, 1880. pp. 51-55. Sketch of the Geological History of Lake Lahon- tan. Third Annual Report of the U.S. Geological Survey. Washington, 1883. p. 202. A Geological Reconnoissance in Southern Oregon. Fourth Annual Report of the U.S. Geologi- cal Survey. Washington, 1884. pp.442-455. Lake Lahontan. Monograph No. XI, U. 8. Geological Survey, pp. 24-28, 274-284. Mr. Gitpert remarked that the section exhibited by Mr. Diller appeared to demonstrate a history comprising (1) the folding of the slates and the formation of several faults and associated monoclines, (2) the general degradation of the country until the monoclinal ridges were approximately obliterated, and (3) a re- newal of movement on the old fault lines, giving rise to the exist- ing topography. 8 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. Wiis remarked that in 1883 he had had opportunity to study the Cascade Mountains north of the regiom described by Mr. Diller. The Sierra structure is apparently not found in the north- ern part of Washington Territory, and the eastern face of the Cascade range is probably not characterized like the Sierra by a great fault. Mr. Drier concurred in the statement that the Cascade range is built essentially of igneous rocks, and is not characterized by great faults, at least along its eastern base. The topography of the Sierra has entirely changed since the deposition of the auriferous gravels, and some of the fault move- ments are so recent that the stream terraces to which they have given rise are still preserved. Mr. G. K. GILBERT made a communication on RECENT CHANGES OF LEVEL IN THE BASIN OF LAKE ONTARIO. [The substance of this communication was presented to the American Association for the Advancement of Science at Ann Arbor, and appears in abstract in Science, Vol. VI, p. 222.] Remarks were made by Mr. E. Farqunar. 280TH MEETING. JANUARY 30, 1886 The President in the Chair. Fifty-five members and guests present. The Chair announced the appointment of the Committee on Communications. Mr. Greorce E. Curtis made a communication on LIEUTENANT LOCKWOOD’S EXPEDITION TO FARTHEST NORTH. [Abstract. ] The paper opened with a reference to the statement in the Ency- clopedia Britannica (article, Polar Regions, p. 326,) that “all this region [the northern coast of Greenland and the interior of Grinnell GENERAL MEETING. 9 Land] had already been explored and exhaustively examined by the English expedition of 1875-76.” A refutation of this state- ment was not now necessary inasmuch as a retraction had already been made; but an impartial examination of Lieut. Lockwood’s observations was still required as a basis for our own confidence in the latitude attained. A description of the equipment of the expedition was given, with a sketch of the events of the journey, and extracts from the narra- tive report. The weights of the food and equipments drawn by the dog team furnished the basis of a discussion as to the value of dogs in arctic sledging. The weight ot’ food taken for the support of each man was about twice that taken for each dog. Now if a man can drag a sufficiently greater amount to compensate for the greater weight of his food, it is immaterial whether the motive force used be dogs or men. On this expedition the dog sledge was actually loaded so as to give a weight of about 100 lbs. to each dog; but the maximum weight that can be advantageously drawn by a man is only 125 or, perhaps, 150 lbs. The ratio of effective work performed to the weight of food consumed is, therefore, materially greater for dogs than for men, so that a substantial economical advantage is obtained by using dogs instead of men for sledge dragging. This advantage seems not to have been appreciated by the English ex- pedition of 1875’-76, whose heavy sledges and equipments were all drawn by hand. In addition to the more conspicuous causes of the failure of Lieut. Beaumont’s expedition on the Greenland coast, the neglect to make use of dogs must be added as an important element. The sextant observations made by Lieut. Lockwood for determin- ing the position of his farthest north were shown to be highly satisfactory. Sets of circum-meridian observations for latitude were made at midnight of May 14th and at noon of May 15th. The conditions of observation offer no sufficient reason for giving more weight to one set than to the other. The mean of these results gives 83° 24’ as the latitude attained by Lieut. Lockwood, and an uncertainty not greater than 1’ represent the accuracy of its deter- mination. The paper closed with the following tribute to the character of Lieut. Lockwood as an arctic explorer : I cannot close this review of Lieut. Lockwood’s expedition to farthest north without turning from the cold discussion of the astro- 10 PHILOSOPHICAL SOCIETY OF WASHINGTON. nomical and geographical records to speak of him of whose life and labors they constitute an imperishable memorial? The success of the expedition was not the result of chance, but was due to Lieut. Lockwood’s thorough knowledge of the details of such an undertaking, and to his indomitable energy in its execu- tion. During the preceding winter he had devoted himself to preparation for the work; had made a careful study of the man- agement and equipment of previous sledging expeditions—especially those of the English in 1875~’76—and profiting by the experience of his predecessors was able to avoid their mistakes. Lieut. Beau- mont’s journey on the Greenland coast was impeded by the heavy sledge, and the heavier equipments with which it was weighted. Lieut. Lockwood’s extraordinary distance was attained with a light sledge drawn by dogs and loaded with nothing but food and the barest necessities of a camp. Regardless of all personal comforts, everything was sacrificed to the objects of the expedition. Under the instruction of Mr. Israel, the young astronomer: Lieut. Lockwood had familiarized himself during the winter with all the astronomical observations necessary to be made by an ex- plorer, and with the return of the spring sun applied himself to practical observations with the sextant until he became an expert in its use. So good was his astronomical work that the accuracy of his observations is dependent only on the variability of the in- strument and the difficulty of the conditions of observation. In addition to a practical knowledge of arctic sledging, the expe- dition was undertaken with a determined energy of purpose, those qualities expressively termed “ grit” and “ pluck,” which no obstacle could defeat. Retaining only two companions at Cape Bryant, he sent back his supporting party and continued his advance over an unknown coast. Suffering continuously from cold, hunger, or fatigue, he pushed on with unflinching perseverance until one hun- dred and fifty miles of new coast were traversed and the national colors unfurled in the highest latitude ever attained by man. Simply to go a little nearer the pole than his predecessors was not, however, the controlling object of this expedition. Lieut. Lockwood’s own motives, as we read them in his journal, were these: “My great wish is to accomplish something on the north coast of Greenland that will reflect credit on myselfvand on the ex- pedition.” Inspired by this praiseworthy ambition, his skillful management resulted in its most successful realization. His mo- GENERAL MEETING. 11 tives were not those of the visionary and enthusiast who “knows nothing and fears nothing,” but of an earnest practical explorer whose ambition is to add something to the world’s knowledge of the planet on which we live. The literal fidelity of his narrative, its freedom from an exaggeration that has too often marred the records of previous Arctic explorers, the exact and painstaking descriptions, and the careful distinction between what is seen and what is inferred, all bear witness to his conscientiousness in the search for truth. As an important element in the success of Lieut. Lockwood’s ex- peditions, due recognition must be given to the cordial, sympathetic and able co-operation of Sergeant Brainard. Chosen by Lieut. Lockwood to continue the journey to Cape Bryant, when all the remainder of the party returned, it was Brainard who pushed onward with him over one hundred and fifty miles of that desolate coast and reached the farthest north. It was likewise Lockwood and Brainard who a year later, in May, 1883, explored the interior of Grinnell Land and looked out on the shores of the western polar sea. But only one of these companions in exploration was destined to reach home to receive the honor due to their heroic achieve- ments—honor due, but, as yet, awarded neither to the living nor the dead. The story of the return is known to all, but perhaps not Lieut. Lockwood’s wonderful cheerfulness of spirit through that last terrible winter at Cape Sabine with death staring him in the face Lieut. Lockwood died on April 9, 1884, “from action of water on the heart induced by insufficient nutrition ’’—the official euphemism for starvation. This record of indescribable suffering, privation and death, following that of two years of heroic endeavor and achievement, is a tragedy which appeals to human hearts with a force unequalled by any story of fiction or by any drama of the stage. To Lieut. Lockwood’s achievements are applicable the familiar lines of Horace : ‘‘ Hxegi monumentum aere perennius Regalique situ pyramidum altius, Quod non imber edax, non Aquilo impotens Possit diruere, aut innumerabilis Annorum series et fuga temporum.”’ Woven into the history of arctic discovery and engraven on our 1a PHILOSOPHICAL SOCIETY OF WASHINGTON. maps, the substantial results of Lieut. Lockwood’s explorations form a tablet more enduring than brass, which the corroding storm, the fierce north wind, and the flight of ages cannot efface. In reply to a question by Mr. Mussey, Mr. Curtis stated that the time for longitude determination was obtained from one ordinary watch of good quality, and one pocket chronometer. Messrs. Datu and Rosrnson discussed the advantages and disadvantages of the use of dogs in arctic sledging, and attention was called to the im- portance of using snow shoes, and of coating the sledge runners with ice. Mr. O. T. Mason made a communication on TWO EXAMPLES OF SIMILAR INVENTIONS IN AREAS WIDELY APART. [Abstract. ] Anthropologists assign similar inventions observed in different parts of the world to one of the following causes : 1. The migration of a certain race or people who made the in- vention. Upon this theory similar inventions argue the presence of the same people or race. 2. The migration of ideas—that is, an invention may be made by a certain race or people and taught or loaned to peoples far removed in time and place. Upon this theory similar inventions argue iden- tity of origin, but not necessarily the consanguinity of those who practice them. 3. In human culture, as in nature elsewhere, like causes produce like effects. Under the same stress and resources the same inven- tions will arise. Now, the question arises, which of these causes shall be invoked in specific cases to account for resemblances. We must first examine the word resemblance. Taking Aristotle’s four causes: ‘The material cause, ex qua aliquid fit. The formal cause, per quam. The efficient cause, a qua. The final cause, propter quam. We must enlarge upon them as follows: Every human activity involves six fundamental considerations. 1. The agent, or efficient cause. GENERAL MEETING. ° 13 2. The material cause. 3. The implemental cause. 4, The formal cause. 5. The processive cause—that is, the exact order and method of the action. 6. The motive or function. | We might, also, include a series of concomitants, such as techni- eal vocabulary, all sorts of traditional lore and myths, social or- ganization, and even religious rites. Again, some of the six’causes are themselves generally the out- come of other causes, so that we have concatenations and genealo- gies of causes. Now for the application. Most men, when they say this thing resembles that, have reference only to one of our six causes. They mean simply that there is resemblance in form, or material, or technical method, or function. My plan would be to submit such resemblances to scrutiny to ascertain how far they extend, and, also, to examine resemblances known to be consanguine, or borrowed, or independent, to ascertain which of our characteristics are pecu- liar to them. In that way an inductive system of rules would be adduced. The two independent inventions which I exhibit are a beginning in that direction. One is a stitch in basketry, found only at Cape Flattery and on the Congo. This stitch is common enough in fish- traps, wattling fences, and cages, but in only these two areas have people thought to apply it to close basketry. It consists of vertical warp, a horizontal second warp, laid behind the first, and a coiling or sewing of these two together, so as to show a diagonal stitch in front and a vertical stitch inthe rear. Here the resemblance is in method alone. In all other respects the inventions differ. The other invention referred to is the throwing-stick of Austra- lians, Puru Purus, and Eskimo. These agree, in motive or func- tion and in the fundamental idea of a staff and a hook. Beyond this the Eskimo have invented a dozen additional attachments never dreamed of by the others. Mr. Murpocs supplemented the enumeration of throwing sticks by describing an undeveloped form used by the Siberian Eskimo. In reply to a question by Mr. Goode, Mr. Mason stated that he had not seen the Brazilian sticks; they are mentioned by many 14 PHILOSOPHICAL SOCIETY OF WASHINGTON. travelers. Mr. Mann and Mr. Murpoca described the manner in which the throwing stick is used by Eskimo in kyaks. The motion centers in the wrist and not the elbow or shoulder. 281st MEETING. FEBRUARY 13, 1886. The President in the Chair. Fifty-five members and guests present. . Mr. J. H. Kipprr communicated an HISTORICAL SKETCH OF DEEP SEA TEMPERATURE OBSERVATIONS, illustrating the subject by numerous diagrams and by a collection of deep sea thermometers. Mr. E. B. Exxuiorr made a communication on the ANNUAL PROFIT TO BANKS OF NATIONAL BANK NOTE CIRCULATION, and a second communication on the QUANTITY OF UNITED STATES SUBSIDIARY SILVER COIN EXISTING AND IN CIRCULATION. In these papers he developed the formule used in computing cer- tain tables embodied in the report of the Comptroller of the Currency. Remarks were made by Messrs. Mussey and LAWRENCE. Mr. AsAPH HALL read a paper on THE NEW STAR IN THE NEBULA OF ANDROMEDA, giving an historical account of its discovery, growth and decadence. [This paper is printed in the American Journal of Science, 3d se- ries, vol. XXXI, p. 299.] GENERAL MEETING. 15 282p Mretina. Frepruary 27, 1886. The President in the Chair. Fifty-six members and guests present. _ The Chair announced the election to membership of Mr. GrorGE JOTHAM CUMMINGS. Mr. AsApH HALL made a communication on THE IMAGES OF STARS, which was discussed by Messrs. Eastman, Curtis, and PAUvt. [This paper is published in the Sidereal Messenger, April, 1886.] Mr. R. S. WoopwarD made a communication ON THE CHANGES OF TERRESTRIAL LEVEL SURFACES DUE TO VARIATIONS IN DISTRIBUTION OF SUPERFICIAL MATTER. [To appear as a Bulletin of the U. 8. Geological Survey. ] He was followed by Mr. G. K. GitBert with a paper ON THE OBSERVED CHANGES OF LEVEL SURFACES IN THE BONNE- VILLE AREA, AND THEIR EXPLANATION ; and Mr. T. C. CHAMBERLIN then began a paper ON THE VARYING ATTITUDES OF FORMER LEVEL SURFACES IN THE GREAT LAKE REGION AND THE APPLICABILITY OF PRO- POSED EXPLANATIONS. 2838p MEETING. Marca 138, 1886. Vice-President Harkness in the Chair. Thirty-nine members and guests present. The Secretary read a letter from the Secretary of the Council of the Anthropological Society, inviting the members of the Philo- sophical Society and their friends to attend the annual meeting of 16 PHILOSOPHICAL SOCIETY OF WASHINGTON. the Anthropological Society and listen to an address by its president, Major J. W. PowEL. " The Chair announced the election to membership of Messrs. Car- Los ALBERT KernastTon, RoLAnD Durr Irvine and ARTEMAS MARTIN. Mr. T. C. CHAMBERLIN completed his communication ON THE VARYING ATTITUDES OF FORMER LEVEL SURFACES IN THE GREAT LAKE REGION AND THE APPLICABILITY OF PROPOSED EXPLANATIONS. Remarks were made by Mr. Dutron. Mr. R. D. Irvine made a communication on THE ENLARGEMENT OF MINERAL FRAGMENTS AS A FACTOR IN ROCK ALTERATION, which was discussed by Messrs. Ippines, DitteR, Durron, and LAWRENCE. 284TH MEETING. Marca 27, 1886. The President in the Chair. Thirty-three members and guests present. Mr. I. C. RusseLt made a communication on THE SUBAERIAL DECAY OF ROCKS AND THE ORIGIN OF THE RED CLAY OF CERTAIN FORMATIONS. This was discussed by Prof. Joun 8. Newserry, of New York city, and by Messrs. Goopr, Darton, IrvinG, and CHAMBERLIN. Mr. Romyn Hircucock made a communication on RECENT IMPROVEMENTS IN MICROSCOPIC OBJECTIVES, WITH DEMON- STRATION OF THE RESOLVING POWER OF A NEW 1#16TH INCH. Remarks were made by the President. GENERAL MEETING. 17 Mr. Henry Farquuar read a communication on 4 A FONETIK LFABET. [Abstreekt.] Ais xlfabet cendertéyks tu reprizént de sawndz av Iyglic spiyte ez ytiwjuwali herd, bai twénti-nain létcerz. Av diyz 6, d, f, 9, h, k, 1, m, n, p, 7, 8, t, v, w, y end z hev der keestomeri sawndz; ¢ hez its sawnd «ez in benificiert [beneficiary ] —a sawnd akéyjcenali given tu s or t or ch, or mower 6fen tu sh; 7 iz kanfdind tu its Frente sawnd — hwite iz ool det iz left tu it hwen kambdind wid d in Iyglie, vez in edjutent [adjutant]; hwail de néyzal ytiwjuwali riten ng, ée th fleet send th carp, ar given bai de léteerz y, 06 end , biérod fram de Griyk wlfabet. Av de vawels, a iz xz in wad or bar, e xz in pet, 7 xz in pit, o ez in on or or, wu ez in put; hwail de ddigrefs @ end @ ar yuwzd for de vawel sawndz heerd in beet [bat] send in bet [but; won, burr, stir, herd, heard, word, ete. ]. Deeblld létcerz indikeyt proléoyd sawndz: Z in dabll [double], m in prizmm [prism], a in stéari [starry], 0 in doon [dawn]. C&dcer loy véwels ar rigdrded sez impytier sawndz; end sloerz bifécer r ar dindwted bai @, téndensi tu klowz wid de lips bai w, zend wid de toy bai y, falowiy a cort vawel; dees wiy heev ew, ta, ow, we in beer, bier, boer, buer [bear, beer, bore, boor], aw, ow, ww in haws, flow, buwt [house, flow, boot], ey, iy, ay in beyt, biyt, bayt [bait, beat, bite]. 2&z egzempllz av dcr kam- binéyccenz, oil, wain, yuwz2, tényur, kyuer [oil, wine, use, tenure, cure] mey biy given. Ztksénted vdwelz ar markt, sékanderi xksents (sez on de foerst silabll ay vériabiliti) heviy de greyv sain, prinsipal weenz oe zekytiwt. Owiy tu de pdweerful influwens av de skuwlz in kiypiy cep zen ek- sésiv réveerens for de kanvénccenal stendard av spéliy, end tu de feekt dset de meedjériti av de weerdz av dweer leeygwedj ar nown tu cs bai der epicrens xz printed or riten redcer dn bai der sawnd xz spowken, der iz litll imifydiet préspekt av sceksés in de “spéliy- riform” mtiwvment, hwite eymz tu divélap d4woer spéliy intu woen mocer nfcrli fonétik. Naveerdelés, der ar praktikal ytiwsez for a 39 18 PHILOSOPHICAL SOCIETY OF WASHINGTON. gud fonétik zlfabet. Feerst, it kud fernic a steendard ay proncensiéy- coen in dikeceneriz av ool sorts —huwz riydoerz wud des biy seyvd de tesk av leerniy a diferent sistem for iyte dikcceneri, xz et préz- ent. Sékand, it kud end cud form a régyular brente av instroek- coon in skuwlz, znd dees eesist in sikytceriy yiwniform proneen- ep te siéyceen. Ocerd, scem scete divdys iz olmowst a nisésiti, if wiy wud briy érdeer intu a biznes naw Oltugédcer keyatik ; treensliteer¢ycceen av neymz fram de Riwean, Brabik znd ceder leygwedjez nat yawziy de Rowman elfabet. Zz wiy filo now méJad kansistentli set préz- ent, der wud peerheps biy now greyt difikelti in estxbliciy ween; espécali if bai it de sayt av a neym kud giv en sepraksimet aidia haw it iz prondwnst bai dowz mowst feemiliar wid it. Mr. Mussry said that the principal difficulty in all phonetic alphabets was not in the alphabets themselves, but in the existing variety of pronunciation and the disagreements as to the true pronunciation of words. Pitman’s phonetic system—little short of an inspiration—was to his mind the best ever devised for practical use, though Bell’s system of visible speech enabled a person familiar with it to correctly pronounce words and sentences in any language whatever. Mr. Mauuery said that he had been connected with the prepa-. ration of a phonetic alphabet by the Bureau of Ethnology, with the object of collecting and recording the vocabularies of the languages of the North American Indians. In addition to the requisite that there should be a distinct character for every sound, it was made a fundamental rule that the characters should be limited to those in an ordinary font of English type, embracing however not only the Roman alphabet but such characters and dia- critical marks as the printers’ cases of average newspapers could furnish. This was accomplished so as to provide for many more sounds than are included in Mr. Farquhar’s scheme, yet without resort to the Greek letters used by him in several instances. It was done by the simple device of reversing the large number of letters in the Roman alphabet which present a markedly different appearance when so reversed, from*their erect position. This is entirely convenient to the printer and does not occasion awkward- ness in the current script to the recorder or writer for the press, as GENERAL MEETING. 19 it is only necessary to mark the letter intended to be reversed, after writing it in the normal manner, and to notify the printer accord- ingly. In practice the letters intended to be reversed are marked by a cross beneath them, though a still more current method of distinction would be by the cedilla in using which the pen or pencil is not removed from the letter as formed. This is however more convenient to the writer than to the printer. The result of this scheme in practice has solved one part of the problem of a universal phonetic alphabet. Vocabularies and chrestomathies of unwritten languages have been recorded and printed, upon which grammars and dictionaries have also been pre- pared and printed, and from them the languages can be learned so as to be spoken intelligibly without oral instruction. The possibility of the use of such an alphabet with only such modification as would increase its simplicity, in the reform of the English literation, is not to be doubted, in view of its success under more difficult conditions. The actual obstacles to phonetic reform of fixed alphabets are, though perhaps insuperable, non-essential in the scientific view of the question. Concerning the gliding sounds mentioned by Mr. Farquhar, Mr. DoouittLE remarked that some of these appeared to be essential, while others were only accidental. 285TH MEETING. APRIL 10, 1886. The President in the Chair. Fifty-nine members and guests present. The Chair announced the election to membership of Messrs. ALEXANDER GEORGE McAptIr and Ropert THomas HI ut. Mr. MALLERY read a communication on CUSTOMS OF EVERY-DAY LIFE. [Abstract. ] The scope of the paper excluded the more commonly noted cere- monial institutions, such as appear in regal courts, courts of justice, and legislative bodies, and embraced the ordinary modes of behavior among civilized people. These all have history and significance, 20 PHILOSOPHICAL SOCIETY OF WASHINGTON. are not the result of deliberate invention or convention, and in their present shape clearly exhibit the laws of evolution, though not always in the directions set forth in text-books and treatises on sociology, Comment was made upon the topics of social etiquette, precedence, titles, grammatical forms of personalty, the address and signatures of letters, forms and practices relating to written invitations and to social visits, and formularies of oral greeting, with examples or illustrations under each topic. Fashion was distinguished from custom as being imitative and transitory, although in some few instances genuine merit in a fashion led to its permanent adoption under the same law with which the convenient and useful portions of old customs have survived in modifications. Two points on which the paper specially declared disagreement with Herbert Spencer relate to the bow in salutation and to the hand-shake or grasp. The bow Mr. Spencer regards as but modi- fied from the natural expressions of physical fear and bodily subjec- tion noticed among sub-human animals and the lowest tribes of men, originating in actual prostration and groveling to which crawling and kneeling succeed, and the bow is but a simulated and partial prostration. A large class of obeisances doubtless had their origin in the attitudes of fear, and several were adduced in addition to those mentioned by Mr. Spencer, but it was contended that the sub- ject of the bow is much more complex than as presented by him, a separate and independent course of evolution being suggested. Evidence was collected from many sources, and especially from ges- ture speech, relating to the concepts of, and expressions for, higher and lower, superior and inferior, assent, submission and respect, all connected with the forward and downward inclination of the head in salutation. Regarding the uncovering of the head as a part of the masculine bow, the paper offered to Mr. Spencer a new illustra- tion of militancy, too often insisted upon in his Synthetic Philosophy but not definitely in this connection. The voluntary deprivation of removable head gear—once defensive—is often a mark of defeat and subjection. The modern formal military and naval salutes contain the same idea that the saluter is actually or symbolically powerless. Therefore the action of the removal of the hat, the present repre- sentative of the casque, helmet, or morion, is better"adapted to a “surrender” theory than to that of pretended “beggary” advocated by Mr. Spencer. GENERAL MEETING. yA That great writer believes that the hand-shake originated in a struggle, first real, afterwards fictitious, in which each of the per- formers attempted to kiss the hand of the other, which was resisted, thus producing a reciprocating movement of the joined hands. In examining this explanation the antiquity and prevalence of the kiss in salutation was questioned. The mutual kiss of affection or pas- sion by the lips between opposite sexes is not found among the lower tribes and is probably not of great antiquity. It was preceded without reference to sex by patting, stroking or rubbing different parts of the body—smelling and'sniffling being also common. The kiss of the hand is undoubtedly ancient and gestural, and is ap- parently not derived from that of the lips, which is gustatory. In- stances were admitted of the identical friendly contest for priority in kissing hands relied on by Mr. Spencer, but they were consid- ered to be connected with the topic of precedence as secondary, the joining of hands being primary and wholly unconnected with a “shake” or any motion after junction. Evidence was presented that the junction of hands in testimony and in expression of agree- ment and friendship is of too high antiquity and universality to be derived from a pantomimic contest about precedence for the compara. tively modern and limited kiss. Mr. Mason expressed the opinion that not all customs are indi- rectly derived, and cited the innovations of the day as instances of customs deliberately assumed for a definite purpose. Mr. MENDENHALL referred to the numerous ways in which Jap- anese customs are the inverse of ours. In beckoning, the fingers are turned down instead of up, and this is probably explained by the fact that in Japan those who are beckoned—namely, inferiors—are by custom or in theory prostrate. The kitchen of a hotel is placed at the front against the street. A horse is backed into the stable and led out. It is a matter of etiquette, and modesty also, that ladies turn their toes in. The Japanese do not shake hands; the bow is very low, and is begun twenty feet away. There is no kiss of cere- mony or friendship, but the kiss exists as an expression of passion. Japanese children play all the common games of our children in some modified form, except marbles. In reply to a question by Mr. Mason, Mr. MenpDENHALL said that a Japanese does not shake his own hands as a salutation to 22 PHILOSOPHICAL SOCIETY OF WASHINGTON. another, but may join them in bowing as a merely accidental atti- tude. Messrs. E. FarquHar and Mussry spoké of the antiquity of kissing as indicated by Hebrew and Greek literature. Other remarks were made by the President and by Mr. CLARKE. Mr. R. D. Mussey made a communication entitled WHEN I FIRST SAW THE CHOLERA BACILLUS. 286TH MEETING. APRIL 24, 1886. The President in the Chair. Thirty members present. The President communicated an invitation from the American Historical Association to attend its sessions of April 27-29. Mr. G. Brown Goope and Mr. T. H. Bean made a joint com- munication on THE DISTRIBUTION OF FISHES IN THE OCEANIC ABYSSES AND MIDDLE STRATA. Remarks were made by Messrs. Paut, Harkness, BILurnes, DoouitrLeE, GooprE, WELLING, and Taytor, and by Prof. Epwarp D. Cops, of Philadelphia. Mr. GILBERT THOMPSON made a communication on THE PHYSICAL-GEOGRAPHICAL DIVISIONS OF THE SOUTHEASTERN PORTION OF THE UNITED STATES AND THEIR CORRESPONDING TOPOGRAPHICAL TYPES, [Abstract. ] Having charge of the geographical work carried on by the U. S. Geological Survey in that portion of the Appalachian region south of Pennsylvania and the Ohio river, I have had occasion to con- sider the classification of the region from the point of view of the geographer. It has previously been divided by many authors and into numerous sections, the basis of classification being geological botanical, agricultural, or commercial, and usually from a local standpoint. For my purposes the principal basis of classification is the character of the topographic relief, but this is so closely GENERAL MEETING. 23 related to the features controlling other classifications that a large share of the boundaries coincide with lines previously drawn and the selection of appropriate designations is little more than a choice between names previously given. There are some parts of the United States where the drainage basin affords the best unit for the purposes of the physical geo- grapher. This holds for the basin of the Laurentian lakes, the basin of the Red River of the North, and the great Interior basin. But in the Appalachian region the drainage cannot be used. There is how- ever in this region a remarkable line of demarcation, known as the fall line, which finds its manifestation in connection with the drain- age, and is the natural boundary of an important division. If we follow the course of any river in the eastern part of the United States, south of New England, from its source to the sea, we discover that at a certain point it ceases to be rapid and turbulent, and becomes broad and slow-moving, and in many cases an estuary of the sea. At the point where this change occurs there is usually a fall or rapid. The familiar local example is the Potomac at Little Falls. I have traced this fall line from near Troy, N. Y., southward by the interior cities of Washington, Richmond, Colum- bia, and Montgomery, and thence to the Muscle Shoals of the Tennessee river. It is always the lower limit of water power and often the upper limit of navigation, and is therefore marked, and destined to be marked, by cities and towns of importance. In its northern portion it is at the head of tide, and nowhere does it exceed an altitude of 200 feet. It may yet be determined that it crosses the Saint Lawrence at the Lachine rapids and the Missis- sippi above Cairo, although no rapid exists at that point. Whether it may be traced farther and into Mexico remains to be determined. From the fall line to the shore of the sea there is a region having a gentle slope, traversed by slow-moving rivers, and fringed at al- most a dead level by deltas, swamps and everglades. This I have entitled the coastal plains, including as subdivisions the Atlantic plains and the Gulf plains. The area bounded by the fall line and by the Mississippi and Ohio rivers and a part of the drainage divide of the Laurentian lakes, might be taken as a whole as the Appalachian region, but it includes three sections so distinct in topographic type as to warrant separate designations. From the Ohio river southeastward and from the Mississippi 24 PHILOSOPHICAL SOCIETY OF WASHINGTON. eastward the country gradually rises until it reaches an altitude of about 2500 feet above sea level, where it is genexally cut off by an escarpment facing to the southeast and about 1200 feet in height. The composite name of Cumberland- Allegheny - Catskill plateau would serve to define it, but for brevity I have designated the whole as the Cumberland plateau. Its general topographic character is that of a table land deeply cut by a system of ramifying drainage. At the north the surface is somewhat rolling, and the plateau ends at the south in long, finger-like spurs. Its rivers and streams rise generally near the edge of the escarpment and flow toward the northwest. The Potomac however breaks across the edge and flows eastward, while the New and Tennessee rivers enter the plateau from the east and flow westward. 7 From the Cumberland plateau eastward to the eastern foot of the Blue Ridge lies a belt to which the name of Appalachian re- gion is applied in a restricted and definite sense. It is characterized by numerous long, narrow mountain ridges, closely parallel to each other and bending in sympathy with the local curvature of the belt. Through large areas they are approximately uniform in height, but elsewhere they are unequal. Ina notable belt, every- where recognized in the local nomenclature as a valley, and travers- ing the region from north to south, the ridges are so low that they rank only as hills. At the north the principal mountain area lies west of the great valley and only the Blue Ridge on the east. At the south the valley lies close to the Cumberland plateau, and the Blue Ridge is expanded into a broad mountain district, culminating in Mt. Mitchell (6711 feet), the a sii summit east of the Rocky Mountains. The remaining area is the Piedmont region, an undulating plain, diversified by low spurs from the mountain region, and occasional isolated hills of considerable elevation. The streams are rapid, and the topographic relief gradually diminishes toward the fall line. The communication was fully illustrated by maps and topographic sketches, and by a profile from Louisville, Kentucky, to Charleston, South Carolina. Remarks were made by Messrs. GILBERT, HARK- NEss and Cope. GENERAL MEETING. 25 287TH MneEtINnG. May 8, 1886. The President in the Chair. Thirty-five members present. The Chair announced the election to membership of Messrs. JosEPH Hammond Bryan and Merwin MARIE SNELL. Mr. Tuomas RussELu made the following communication on TEMPERATURES AT WHICH DIFFERENCES BETWEEN MERCURIAL AND AIR THERMOMETERS ARE GREATEST. Glass and mercury do not expand uniformly. An increase in temperature of one degree at one hundred degrees causes greater changes of volume than the same increase at zero. (In all refer- ences here to degrees and temperatures the centigrade scale is to be understood.) Normal mercurial thermometers, when corrected for their various ‘errors of construction, differ among themselves and also from the air-thermometer. At 40° the mercurial thermometer reads about 0.°2 higher than the air-thermometer. At— 38.°8, the melting point of mercury, it reads about 0.°2 lower. The quality of mercury in a thermometer has an influence on its reading. A thermometer containing roo00 of lead in the mercury will read 0.°5 lower at 50° than if the mercury is pure. [H. J. Green.] Comparisons have been made at the Signal Office between an air- thermometer and a number of mercurials. Some deductions have been made from the results of this work as to the temperatures at which the differences between the two thermometers are greatest. From the same results there have also been derived values of the coefficients of expansion of glass dependent on the second and third powers of the temperatures. It is to these I wish to call your at- tention. The air-thermometer used was of the kind that measures tem- peratures by the varying pressure of a quantity of air kept at a constant volume. Five Tounelot mercurial thermometers were compared with this air-thermometer at temperatures from 0° to 55°. Two Baudin thermometers were compared with it from 0° to — 38.°8. The freezing points of mercurial thermometers rise with age. A few days after a thermometer is filled this rise may amount to a 26 PHILOSOPHICAL SOCIETY OF WASHINGTON. whole degree. In a year after that it may rise an additional five- tenths of a degree; with succeeding years the *change is less and less. When a thermometer is raised to a high temperature its freezing point is depressed. The average depression for 100° is about 0.°2. On raising to a temperature lower than 100° the freezing point is also depressed, but not so much. For 50° the depression is about 0.°05. For temperatures as high as 100° the depressions are about proportional to the squares of the temperatures by which they are produced. The cause of these changes of freezing point is in the nature of the glass. The mercury in the thermometer has nothing to do with them; neither has the atmospherig pressure. The amount of the changes depends on the composition of the glass in the thermometer-bulb. It has been recently ascertained by H. F. Wiebe that the change is greatest for glass containing equal quantities of potash and soda. A thermometer made of a variety of glass containing 14 per cent. of potash, 14 per cent. of soda, the remainder silica and oxide of lead, was found to have its freezing point depressed 0.°84 on raising it to 100°. Thermometers in which the potash or soda in the glass was replaced by lime were found to have the freezing points depressed only 0.°07 for the tempera- ture of 100°. To produce the maximum depression of freezing point peculiar to any temperature requires that the thermometer be kept at that temperature for a certain length of time. For a temperature of 100° a half hour suffices; for 50° two hours are required. If the thermometer is kept at 100° longer than half an hour the depressed freezing point after that time begins to rise. If con- tinued at the higher temperature for two weeks the freezing point at the end of that time will be found to have risen about one degree. This fact is taken advantage of by some makers of thermometers to produce an instrument whose freezing point will vary but little in years subsequent to its manufacture. The depression of freezing point produced by high temperature is only temporary. ‘The thermometer in the course of time regains the reading of its freezing point corresponding to ordinary tempera- tures. The more quickly the depression is produced the more slowly the reading is regained. After a thermometer has been subjected to a temperature of 100° GENERAL MEETING. 27 it will regain its ordinary freezing point reading in one month. The change in the first part of this period is much more rapid than towards the end. To recover the depression caused by 50° re- quires only two days. The older a thermometer the more quickly it gains its freezing point corresponding to ordinary temperatures. An instrument forty years old will regain its freezing point after exposure to 100° in one week while an instrument three years old requires a month. The more alternations of temperature a thermometer is subjected to the more quickly its freezing point rises. A thermometer subjected to a very high temperature, as 350°, will will have its freezing point raised from 12° to 20°. This rise is © not due to softness of the glass at the high temperature and a con- sequent diminution in the volume of the bulb by the atmospheric pressure. This is shown by experiments with weight-thermometers. In these the tubes are open to the pressure of the air and there is as much pressure inside as outside the bulb. As heating to 100° depresses the freezing point while heating to 350° raises it there must be some intermediate temperature for which there is no change. This point is usually at the tempera- ture of about 160° to 180°, but varies widely with thermometers made of different kinds of glass. When a thermometer is subjected to a very low temperature a temporary rise in its freezing point is produced. To produce an appreciable rise requires a long-continued exposure. After being kept twenty-four hours at — 30° the freezing point is found to be about 0.05° higher than at first. One hundred degrees on the centigrade scale is taken as the tem- perature of steam from pure water boiling under a normal barometric pressure equal to 760 mm. of mercury. A variation of 1 mm. in the pressure will change the temperature 0.04°. Zero is taken as the temperature at which pure ice melts when subject to an atmosphere of pressure. An increase of a whole at- mosphere lowers the temperature of the melting point of ice 0.008°. This is to be distinguished from the effect of an atmosphere of pressure on the reading of a thermometer ; by compressing the bulb it causes the thermometer to read about 0.°2 higher than if there was no pressure. The fundamental distance on a normal thermometer is taken as the reading it would have at a true temperature of exactly 100° 28 PHILOSOPHICAL SOCIETY OF WASHINGTON. minus the reading of its depressed freezing point. This, which should be exactly one hundred degrees, rarely isso. When the fun- damental distance is taken in this way it is invariable with age. It is the same forty years after the thermometer is made as four hours after, provided the thermometer is kept at ordinary temperatures. The fundamental distance is not invariable when the raised freez- ing point is used in forming it instead of the depressed freezing point. In this case there is a constant diminution with age as the raised freezing point rises more rapidly than the boiling point. There is not uniformity of practice in the matter of forming the fun- damental distance, but it is greatly to be desired. Heating a thermometer to 350° causes a permanent increase in its fundamental distance between depressed freezing point and boil- ing, varying from 0.°4 to 0.°9. An increase of 0.°4 in the funda- mental distance corresponds to a decrease of sc part in the coefii- cient of expansion of the glass. The total correction of a mercurial normal thermometer for errors in its construction is composed of three parts: 1st. The correction for erroneous fundamental distance. For any temperature this is a proportional part of the differ- ence between the fundamental distance and 100°. 2nd. The calibration correction. This is the correction to the scale marks considered as subdividing the capacity of the tube from 0° to 100° into one hundred equal parts. It involves variations in the bore of the tube as well as irreg- ularities in the placing of the marks. 3rd. The correction at freezing point. This is the amount the thermometer reads in melting ice above or below 0°. At any time it is the observed reading of the thermometer in melting ice immediately after exposure to the temperature measured. Sometimes it is impossible and it is almost always inconvenient to observe the freezing point of the thermometer immediately after observing a temperature. In such a case the position of the depressed freezing point for that temperature must be computed from the law of the variation of the freezing point. It is always prefera- ble however when the highest accuracy is required to ac- tually observe the freezing point. . When a thermometer is put in ice this is what happens: The column falls rapidly at first, then more slowly. Presently it be- GENERAL MEETING. 29 comes stationary ; finally it begins to rise. Fifteen minutes after the thermometer reaches its lowest reading this rise is about 0.°01. It is best-in observing the freezing point of a thermometer to put it in ice thoroughly saturated with water. The ice should be con- tained in a vessel from which the water cannot flow off. A ther- mometer put in ice in this condition takes on the temperature of 0° more quickly than if put in dry ice containing a good deal of air. This method of siicartlaa the freezing point was introduced by Baudin of Paris. There is another correction to a normal thermometer which is little known and rarely applied. Let: V = volume of bulb at 0°. v = volume of tube from 0° to 100° at temperature 0°. = coefficient of cubical expansion of glass. 7 = coefficient of expansion of mercury. T = thermometer-reading corrected for calibration, ete. = true temperature. A consideration of the construction of the thermometer leads to this equation : Vd+)+ed+M 2 -va+y. (1) The volume of the bulb at ¢°, plus the volume of that part of the tube corresponding to the thermometer reading, is equal to the volume of the mercury at ¢°. For ¢= 100 the equation becomes: V+ £100) + + £100) = V1 + 100). (2) Eliminating 7 from (2) by means of its value found from (1) we have: Way T=. par gg (3) Taking as the coefficient of cubical expansion of glass, 2, the quantity 0.000026, the following values are found for 7'— ¢, for the various readings of the thermometer from — 40° to + 100°. fl T—t oC. (a 6 — 40 — 0.145 — 20 — 0.062 0 0.000 + 20 + 0.042 40 + 0.062 50. + 0.065 60. + 0.062 80. + 0.042 30 PHILOSOPHICAL SOCIETY OF WASHINGTON. These are known as the Poggendorf corrections. They are due to the capacity of the tube from the zero to the ome-hundred degree mark, being different at different temperatures. In the following table are shown the results of the comparisons of a certain mercurial thermometer, Tounelot No. 4207, with the air-thermometer : Tounelot No. 4207. Correction . Correction to Scale reading. | as a normal ther- | reduce to the air Differences. mometer. thermometer. °c. ec, °c. oc. 0.0 0.00 0.00 0.00 5.6 + 0.05 + 0.01 + 0.04 11.1 + 0.08 0.00 -- 0.08 16.1 + 0.10 + 0.02 + 0.08 22.2 + 0.15 + 0.05 + 0.10 25.2 + 0.16 + 0.07 + 0.09 30.1 +. 0.20 + 0.09 + 0.11 35.4 + 0.22 + 0.10 + 0.12 40.4 + 0.25 + 0.12 + 0.13 45.1 + 0.25 + 0.16 + 0.09 50.1 + 0.24 + 0.15 -+ 0.09 52.7 + 0.24 + 0.16 + 0.08 55.8 + 0.24 + 0.18 + 0.06 If it be supposed that these differences are due to sensible terms in the expansion of glass and mercury dependent on the squares of the temperatures, an equation can be derived which will show that the maximum difference must be at 50°. But this is not so; the greatest difference is at about 40°. This agrees with what has been found by others. Rowland at Baltimore found the greatest difference at 40° to 45°; Mills in England found it at 35°, and Grunmach in Berlin at 30°. Forming a theory of the differences on the supposition that they depend on the third powers of the temperatures as well as the squares, equation (4) is obtained, which gives the relation between the thermometer reading, 7, and the true temperature, ¢. ee A, ) Sine B, 2 — 4,144,100 baerrneny ta ane y 1+ 4, 1 4%? 100 + Ys — Bs (100)° n— n—?, This is only approximate. The effects of the second and third (4) GENERAL MEETING. 31 powers of the temperatures in changing the capacity of the tube from 0° to 100° are neglected. The capacity of the tube is only 4 part of that of the bulb. f,, 2 2, are the coefficients of expansion for glass for the first, second, and third powers of the temperature. 7,, 7,, 7; are the same for mercury. To make an adjustment of the differences between the mercurial and air-thermometers equation (4) can be put in the form (100¢ — #) x + (10000¢ — #) y + 0.000026?— 0.0026¢+4=0 (5) i Ps ier 8 a proximate than (4) but still sufficiently rigorous for the purpose intended. Forming observation-equations on this model with the observed differences A, as the absolute terms, and solving by the method of least squares, the values of x and y are found to be 2 = — 0.0001391 y = + 0.000000863 Substituting these in (5) it becomes — 0.00788¢ + 0.000165 — 0.000000863# + a = 0. (6) : Ba ‘ he Me Differentiating (6) with respect to ¢ and A, and putting 7, = 0, in which « = anda = T—t. This is less ap- the following quadratic-equation is found 0.0000025897 — 0.000330¢ + 0.00788 = 0, (7) the solution of which gives for the temperatures at which the differ- ences between the mercurial and air-thermometer are greatest t = 31.8 and t= 95.8. To find the temperatures at which the mercurial and air-thermometer agree, put A = 0 in (6); the values of ¢ that then satisfy the equation are t = 0, t= 100, and ¢ = 91. At 32° the mercurial thermometer reads higher than the air- thermometer, at 96°, it reads lower. A curve representing the differences has the following form: 25° 73" z00° Fig. 1.—T 4207 minus Air-thermometer. Abscissas = Temperatures. Centigrade. Ordinates = Differences. 50° 82 PHILOSOPHICAL SOCIETY OF WASHINGTON. This agrees with what has been observed by Dr. Grunmach of the Berlin Aichungs Commission. He found the maximum differ- ence on a certain thermometer to be + 0.°12 at 29.°8, and another secondary maximum of — 0.°04 at 82°. A slight change in the values of « and y will make a large change in the position of the secondary maximum, For another thermometer investigated at the Signal Office this point was found to be at 130°. The values of « and y can be analyzed still further to ascertain whether consistent with known physical properties of glass and mercury. | Taking Broch’s values for the expansion of mercury, which are based on a re-reduction of Regnault’s observations, it is found, adapting the figures to the notation used here, that: y, = + 0.000181792 y, = + 0.000000000175 yg = + 0.000000000035116 Substituting these values of y, and 7, in the equations and aking 3 = 0.000026 we get 8, = + 0.000000021859 2, = + 0.000000000099512 The linear coefficient of expansion of a specimen of glass, such as is used in barometer-tubes and thermometers, has been very care- fully determined by Dr. Benoit of the International Bureau of Weights and Measures. Deriving from this the cubical coefficient,, in the notation used here, we have Dr. Benoit’s values 2, = -+ 0.0000252 8, = + 0.0000000144 It will thus be seen that there is a good agreement between the two values of , found by the two different processes. Remarks were made by Messrs. Gippert, Harkness, and PAUL. GENERAL MEETING. 33 Mr. J. H. Kipper made a communication on THE GILDING OF THERMOMETER BULBS, and was followed by Mr. H. ALLEN Hazen on EFFECTS OF SOLAR RADIATION UPON THERMOMETER BULBS HAVING DIFFERENT METALLIC COVERINGS. [Abstract. ] After showing the importance of shielding from or measuring the effects of solar radiation upon thermometer bulbs used in determin- ing the air temperature and indicating the attempts that have been made in obtaining satisfactory results in the past, Mr. Hazen explained the most recent work of Prof. Wild, of St. Petersburg. Prof. Wild had a bulb coated with copper by the galvanoplastic method, then the copper with gold, which latter was highly polished. From theoretical considerations he established a formula as follows : ~=t,—c¢c(,—4,), in which t, = temperature of air sought; ¢, = that of the metallic- covered bulb; ¢, = that of a black bulb; and ¢ is a constant which he assumed at .15. The published observations indicated a very high reading of the metal-covered bulb, even higher than would have been obtained with a bare glass bulb. Mr. Hazen’s own experiments consisted in comparisons between bulbs as follows:- (1) black, (2) bright, (3, 4) with silver and gold deposited in an exceedingly thin layer and giving a most admirable surface, and (5, 6) with silver and gold deposited on copper as nearly as possible as suggested by Prof. Witp. These thermometers were exposed in sunshine in the open air as well as indoors. It was very difficult to shield from other radiations, dark heat, etc., but it was found that an exposure of two feet from a window pane gave fairly good results. The results are given in the accompanying table. In computing the actual value of ¢, from the formula it was found necessary to take the readings of the black and bright bulbs at each set and compute the ¢, by using .6 as the constant. It was found that the black and bright bulbs were the only ones that did not de- teriorate from day to day. All the metal-covered bulbs were carefully polished each day. 40 84 PHILOSOPHICAL SOCIETY OF WASHINGTON. Comparison of various coverings of thermometer bulbs (out of doors). 7 Bright i lower than Silver Gold Silver Gold Date. Black. black. deposit. deposit. plated. plated. 6 a ¢e. > A ber e. ° Ge] 9 c. ANAT LAs OUsseriace 87.5 7.2 .60 9.0 -29 | 7.0 +65 "| 7.7 49 | 5.8 1.00 PESTO! wi reaxasens 76.3 6.5 -60 8.2 -28 | 6.3 -65 | 6.9 -50 | 5.1 1.04 ek et Watesivas 89.0 4.9 -60 6.3 -24 | 4.7 -67 | 5.5 42 | 3.7 1.11 P20) eee ee 76.8 6.0 -60 Neo 32 | 5.6 -71 | 6.3 52 | 5.1 88 Oe Cees ay 83.9 1.3 60 | 9.2 -27 | 6.7 -75 | T.4 -50 | 5.8 1.02 Se \ Visvtesant 89.3 5.6 .60 7.6 -18 | 5.8 55 | 6.1 48 | 5.0 .80 May = tc. vent 76.9 7.3 .60 9.4 .24 | 6.9 Bs (00) lake Gi 6 52 | 6.3 86 a) Pc aeen 82.8 6.9 -60 8.8 -25 | 6.6 -67 | 7.7 43 | 5.8 ° .89 el Ch 92.1 8.3 -60 | 10.3 27 | 7.9 -66 | 8.2 -60 | 7.6 Py 6’ Meant s tacmece 83.8 6.7 60 | 8.5 -26 | 6.4 Ai Gn | ge i 50 | 5.6 81 The results in this table may be taken as relatively accurate, though the absolute values cannot be relied on. We find the constant in the case of the silver-deposited bulb less than one-half that of the bright or bare glass bulb; the gold-deposited runs a little higher; the silver-plated somewhat lower, while the gold- plated is the. highest of all. In the gold-deposited thermometer the covering was so thin that it showed a green light through. It has been shown that under these circumstances gold transmits a little heat. The gold-plated thermometer gives a remarkable result due partly to the thickness of the metal and partly to a slight roughness, it having been found impossible to deposit a perfectly smooth copper surface as a base. Incidentally these plated bulbs have furnished corroboration of a point presented to the Society some time ago, namely, the effect of a layer of ice upon a bulb in contracting it-at low tempera- tures. It is plain that at the temperature of deposition there would be no effect, but as the temperature was lowered, since the metal contracts faster than glass, the tendency would be to a too high reading of the thermometer—e. g., Thermometer No. 840 gave too high readings at different temperatures as follows: at 12°, 3.6; 30°, 1.4; 40°, 1.0; 50°, .7; 60°, .4, and 70°, .1. Remarks on these communications were made by Messrs. PAut, MENDENHALL, BILLiInes, and WoopWARD. GENERAL MEETING. 35 288TH MEETING. May 22, 1886. Vice-President HarKNEss in the Chair. Forty-eight members and visitors present. Mr. Newton L. Bares read a communication entitled ORGANIC CELLS OF UNKNOWN ORIGIN AND FORM FOUND IN HUMAN FACES (TWO CASES),”* illustrating his remarks by specimens exhibited under the microscope. Referring to the composition of these cells, reported to contain four per cent. of silica, Mr. CLARKE called attention to the desirability of testing for other inorganic substances. In reply to a question as to where in the intestinal canal the cells had been found, Mr. Barrs replied that the evidence in the case indicated the lower part of the canal. ' Mr. J. S. Brnuines made a communication ON MUSEUM SPECIMENS ILLUSTRATING BIOLOGY. [Abstract. ] After referring to the increasing interest on the part of the pub- lic in Biology and Natural History, as theories of evolution, natural selection, etc., are becoming better understood, and to the conse- quent increasing importance of museums or parts of museums in- tended to illustrate the structure and functions of animals, several types of museums were briefly described, including the collection at Florence, the Hunterian Museum, the average Medical School Mu- seum, the museums proposed by Drs. Roberts, Wilder, and Shu. feldt, etc. The special scope and purposes of the Army Medical Museum were stated to be to illustrate: 1. The effects, immediate and remote, of wounds and of those diseases most prevalent in the army, 2. ¢., * These cells are now believed to have come from the banana. If a trans- verse slice of banana is placed in a watch glass and covered with strong nitric acid, two rows of cells become colored and are apparent to the naked eye. A note on the subject may be found in the Boston Medical and Surgi- cal Journal, March 10th, 1883, p. 446. Similar changes doubtless take place by prolonged stay in the intestine, and when found clean and free from vegetable fiber these cells are likely to deceive expert microscopists. 36 PHILOSOPHICAL SOCIETY OF WASHINGTON. the diseases and injuries of adult males. 2. The work of the medical department of an army, modes of transporting sick and wounded, hospitals, medical supplies, instruments, ete. 3. Human anatomy and pathology of both sexes and all ages. This requires many specimens in comparative anatomy and pathology, which are indispensable for a correct understanding of the structure, develop- ment, abnormalities and diseases of man. It is not however proposed to form a museum of comparative anatomy—that belongs to the functions of the National Museum. 4. To show the morphologi- cal basis, or want of such basis, for ethnological classification, more especially: of the native races of America. This includes anthro- pometry and craniology. 5. To illustrate for medical investiga- tors and teachers the latest methods, the newest apparatus, etc., for biological investigation, and various modes of preparing and mount- ing specimens. In connection with this it is hoped to induce origi- nal workers to deposit in the museum type specimens or series of specimens illustrating their discoveries and methods. The classification and arrangement of specimens which it is pro- posed to carry out in the new Museum building were then briefly described. Various modes of preparing specimens were shown, including dissections under spirit, frozen and tinted sections, injections by cor- rosion, ete., and the difficulties in making and preserving such specimens were explained. A second communication on the same subject was made by Mr. G. Brown Goong, and a third, by request, by Mr. FRepERICK A. Lucas, of the National Museum, who spoke more especially of osteological specimens. The papers were all fully illustrated by specimens from the Medical and National Museums. Mr. Grorce P. MrerRILL made a communication ON GEOLOGICAL MUSEUMS. Remarks were made on the general subject of museums and their management by Prof. Epwarp Morsg, of Salem, Mass. GENERAL MEETING. 37 289TH MEETING. OcToBER 9, 1886. The President in the Chair. Seventy-eight members and guests present. The Chair announced the election to membership of Messrs. Coorer CurticE, Henry MitrcHeLtt, Henry Gustav Bryer, and Newton LEMUEL Bares. The subject for the evening was THE CHARLESTON EARTHQUAKE, which was discussed by Messrs. T. C. MenpENHALL and W J Mc- GEE and Prof. CHarLEes G. Rockwoop of Princeton, N. J. Mr. MENDENHALL spoke of the odor observed on Sullivan’s Island previous to the shock, of the time of the clock-stopping shock in Charleston, of the detonations accompanying the various shocks and heard in Charleston, Summerville, and elsewhere, of the torsional movements of monuments, and of the directions in which various structures were thrown down. He exhibited an isoseismal map compiled from data gathered by the U.S. Signal Service. He also stated at second hand a novel theory for the origin of the earth- quake, and spoke of the convergence of opinion of geologists and physicists in regard to the condition of the interior of the earth. He accepted as the time of the clock-stopping shock in Charleston 9h. 51’ 20” Pp. M. Mr. McGee described the geological relations of Charleston, showing that a depth of 2,000 feet of clastic rocks had been demon- strated beneath the city, and that the total depth to the crystalline rocks might be as much as one mile. He described the pheno- mena of deformation of rails and other railway structures, gave in detail an observation of a severe shock at Summerville, described the detonations, and exhibited numerous photographs illustrating the destructive work of the earthquake and the formation of craterlets and sinks. Prof. Rockwoop exhibited an isoseismal map compiled from data gathered by the Earthquake Commission, and characterized by far greater irregularities in the form of contours than were shown by Mr. Mendenhall’s map. He called attention to the fact that nearly all the isoseismal curves show salient angles toward the northwest. He dwelt upon the exceptional nature of this opportunity for earth- quake investigation, and urged that the utmost advantage be taken 38 PHILOSOPHICAL SOCIETY OF WASHINGTON. \ of it. He spoke also of the complexity of earthquake movements, and the difficulties to be overcome in analysing them. He thought that the conspicious inequality in the violence of the shocks at lo- calities not widely separated was to be ascribed to the intersection and combination of rock waves deflected by reflection and refrac- tion. Two intersecting waves would be especially destructive at their nodal points, and comparatively harmless at their points of interference. It was announced by the President that the discussion would be continued at the next meeting. 290TH MEETING. | OcToBER 23, 1886. The President in the Chair. Sixty-seven members and guests present. The discussion of THE CHARLESTON EARTHQUAKE was resumed, the principal speakers being Mr. Everrerr HayDEN and Mr. H. M. Paut. Remarks were made by Messrs. McGeEg, Bruuines, Rosinson, Durron, BELL, CLARKE, and GILBERT, and by Dr. E. P. Howxanp, who was present by invitation. Mr. Haypen first discussed a chart on which were plotted the areas disturbed by earthquakes in the southeastern United States from 1874 to 1885, compiled from Rockwood’s Notes in the Ameri- can Journal of Science. This indicated two earthquake belts, one along the Appalachians, the other along the coast. In the former 28 shocks are recorded, in only 3 of which the area is as great as 1,000 square miles (2 in central Virginia, and 1 in western North Carolina and northern Georgia); in the latter 5 are recorded, only 1 of which (that of 1879 in Florida and Georgia) was at all severe. So far as this evidence goes, therefore, we should have ex- pected a severe shock like that of August 31st to have originated in the Appalachians and to have been orogenic in character, an accompaniment of the gradual elevation of the range. He then proceeded to give a summary of the information which had reached the Geological Survey up to date, illustrating by charts of isoseismal and coseismal lines. The geologic and physical phe- nomena in the region of greatest intensity having been already dis- , iF THE \ CHARLESTON EARTHQUAKE \ from data in the hands of the U. Ss. GEOLOGICAL SURVEY Oct. 23, 1886. Everett Hayden, Asst. Geol., GENERAL MEETING. 39 cussed at the last meeting were not touched upon. The data used came for the most part from correspondence with private parties, although some valuable information had been received from the Signal Service, Light-House Board, and Hydrographic Office—only a small portion, however, of what they would eventually furnish. The State Department had reported that the shock was felt very slightly in Bermuda, and would report later as to Cuba and the Bahamas. The isosetsmals were plotted on an enlarged photograph of the relief model of the eastern United States in the Coast Survey Office, which illustrated the general topographic features more graphically than an ordinary map. In the discussion special attention was paid to explaining their irregular shapes by reference to the surface con- figuration as well as the geologic structure of the country. The inclosed area, marked 4, in West Virginia and Kentucky, well illustrates the fact that a shock may be felt with greater severity beyond a mountain range than in its midst. The similar isolated areas of less intensity in Indiana and Illinois are also typical of variations due to local conformations ; were it possible to plot inten- sities in still greater detail there would doubtless be hundreds of such isolated districts all through the disturbed area. Other points dwelt upon were the unobstructed transmission of the vibrations along the parallel ridges of the range and up the valleys of the Connecticut and Hudson rivers; the obstruction offered by ridges, valleys, and strike of strata transverse to the direction of propaga- tion; and the rapid loss of energy in the sands and alluvial deposits of the northeast coast and lower Mississippi valley. The total land area included within the outer isoseismal is 774,000 square miles, and if we add only half as much more for ocean area it closely approximates to that given by Reclus for the great Lisbon earthquake. Special acknowledgement was made for valuable positive and negative reports received from members of the New England Meteorological Society through their secretary, Prof. W. M. Davis; they accurately fixed the limits of the disturbed area in New England. ' The coseismals were plotted from the most reliable and consist- ent among a hundred or more good time observations, and special care was taken to make them conform to the actual facts, unin- fluenced by any preconceived theoretical ideas. Attention was called to certain peculiarities of these lines, such as their noticeable 3 pS \ 5 CHARLESTON EARTHQUAKE \ from data in the hands of the U. S. GEOLOGICAL SURVBY Oct. 23, 1886. oF Byerett Hayden, Asst. Geol. THE ra ea | aS Tsoseismals baer 5 Bpicentrun *& Coseismals ——— = Note.—Euartiest time 3.51 P. M. (75th Meridian) August 31. 40 PHILOSOPHICAL SOCIETY OF WASHINGTON. prolongation to the northward and southwestward ; the narrow inter- vals where they run along the western flanks of, the Appalachians and across the Florida peninsula; and the wide intervals in the Ohio and upper Mississippi valleys. The following considerations were offered as helping to explain these apparently anomalous fea- tures: The crystalline Archean rocks and parallel ridges of the mountain chain favor a rapid axial transmission of the vibrations, The first tremors spreading to the northwestward, however, are cut. off and deadened by the mountains, so that it isa later phase of the wave which is felt and recorded beyond; having passed the range it then spreads with little obstruction and high velocity through comparatively level strata. Similarly in the littoral and alluvial deposits to the northeast, south, and southwest the earlier tremors are lost and later phases of the wave are successively recorded. It is especially to be remembered that all these times are from non- instrumental observations ; an exact instrumental observation made at Toronto, Ontario, by Prof. Chas. Carpmael (9: 54: 50 P. m.), could not be used here because so early as to be wholly inconsistent with all other reliable but non-instrumental observations. The epicentrum, or point on the surface directly above that part of the deep-lying fissure where the earliest vibrations originated, is placed by these coseismals about a hundred miles north of Charles- ton, which is not at all inconsistent with the fact that the greatest damage was caused in that city. In fact, it is to be expected that the destruction of buildings should be greater at a distance, where the angle of emergence is less. Moreover,'most of the evidence seems to point to a very deep-lying origin, in which case one can- not but attribute much of the local damage, as well as the continu- ance of shocks of considerable intensity but small area, to the character of the recent geologic formations in that region. Borings for artesian wells at Charleston indicate that the Tertiary and Cretaceous strata are very heterogeneous in character—sands, clays, limestone-marls, and imperfectly consolidated beds of con- glomerate, with occasional cavities containing running water—and much of the city is built upon made land. Such considerations may explain the extremely local character of many of the shocks which have been felt at various points in the State of South Carolina since August 31st, as well as the great intensity of the shock at Charleston on that date. Local sinks in the ground are re- ported even in northern Florida, far from the origin of the disturb- GENERAL MEETING. Al ance. An analogous case is seen in the fact that the great destruc- tion of life and property at Lisbon, in 1755, occurred in those por- tions of the city built on weak Tertiary formations, while houses on the firmly consolidated Secondary rocks suffered little damage. The following velocities of wave transmission are indicated : To— Feet per second. Miles per minute. MOMoOMtOe ONtAriO @ see os ee Coe 15,000 170 Wreebington, D.C. 522s Lc) 18,000 148 Prarie dur@hien,, Wise: 224 222-825 . 93800 106 OURO a Soe eee cece Le eOU 141 By way of comparison the following recorded velocities are of interest: Lisbon, 1755, 2,000 feet per second; Naples, 1857, 1775; St. Lawrence valley, 1870, 12,000; England, 1884, 9,200. Reported directions of transmission, while very often what we should expect, are yet generally so contradictory as to be of little value. Similarly the number of shocks felt is recorded so differently by different observers as to be very confusing ; the occurrence of two shocks at a point at some distance from the origin is explained by the hypothesis that the first traveled rapidly through the hard under-lying rocks, and the second more slowly through the softer and more recent strata above. The shock is reported as accom- panied by sounds of greater or less intensity all along the extent of Archean rocks from northern Alabama to Connecticut, and at points on the coastal plain within a radius of about 300 miles from the origin. The coincidence of an unusually high tide is worthy of remark ; the moon was near perigee, and there had been an eclipse of the sun only three days previously. The fact that no sea-wave was caused by the shock confirms the conclusion that the origin was in- land. The weather is generally reported to have been very still and: sultry, although there were no unusual barometric conditions. The summer had been an unusually dry one. Only two other recorded earthquakes in North America can be compared with this in either area or intensity: that at New Madrid, Missouri, in 1811, which was probably fully its equal, and that in the St. Lawrence valley in 1870, equal possibly in area but not in intensity. Mr. Paut explained the generally received classification of earth- quake waves, described some of the results of the Tokio earthquake 42 PHILOSOPHICAL SOCIETY OF WASHINGTON. studies, discussed the relation of destructiveness to amplitude of vibration and to rate of acceleration, and requested Mr. McGee to describe more specifically than at the last meeting the phenomena observed by him in connection with a severe shock in Summerville. Mr. McGee said that during the tremor the bedstead upon which he lay left the floor from fifteen to thirty times, the departures being roughly estimated at three per second. The clear ascent, as judged from the force of the return blow, ranged from one-fourth inch to two or three inches. The bed stood on the ground floor of a wooden house, supported on piers. Earlier shocks had crushed or driven down the piers under the heavier parts of the house, so that the weight was borne in large part by piers under verandas, etc. Mr. Paut said that if the floor in descending separated from the | legs of the bedstead its acceleration of motion must exceed that due to gravitation. The fall of the earth manifestly could not be faster than that of the bedstead. Assuming the accuracy of the observa- tion the only possible explanation would seem to be that the floor had behaved as an elastic spring. Dr. How.anp described a shock observed by himself, and said that of some hundreds of chimneys observed by him in Charleston 75 per cent. had fallen to the west. The PrestpEnt spoke of the bearing of the earthquake upon sani- tary matters. The water mains. in Charleston had been run in some places through sewers, and there is no assurance that these mains are now in such condition as to render contamination im- possible. Mr. Durron inferred from the magnitude of the area through which the shock was felt, as compared with its moderate destruc- tiveness in the central region, that the centrum lay at great depth. Mr. Breit was much interested in the statement that, even at considerable distances from the centre of disturbance, the noise ac- companying the earthquake either preceded the shock or was per- ceived simultaneously with it. This, he thought, indicated that the sound was of local origin. The great velocity with which the earthquake disturbance had been propagated seemed to him to pre- clude the idea of a sound-wave from the centre of disturbance as the cause of the noise perceived. Any sound due to this cause should, he thought, at considerable distances, have been observed after the experience of the shock. He also spoke of the worthlessness of testimony regarding the GENERAL MEETING. 43 direction of sounds proceeding from points below the observer. In this connection he directed attention to experiments relating to Binaural Audition which he had communicated to the American Association for the Advancement of Science in 1879;* and he recommended any one who placed reliance on the testimony that had been adduced relating to the direction of the earthquake noises to try the following experiment: To one end of a long pole attach an ordinary electric call-bell, and at the other end place a push-knob, by means of which the ex- perimenter can at will ring the bell. Let the person whose credi- bility as a witness is to be tested stand with his feet considerably apart, with his eyes closed and head still. The experimenter can then silently move the call-bell into any desired position before ringing, and the observer can indicate his appreciation of the direc- tion of the sound by pointing to the place from whence he conceives it to have emanated, Such being the disposition of the parties the experiment Mr. Bell would recommend is the following: Carefully and silently intro- duce the end of the pole between the legs of the observer so that the bell is directly underneath him. Now ring and ask your wit- ness to indicate by pointing the position of the bell. He had tried the experiment many times, and had been surprised, and even startled, by the result. The observer usually formed a distinct judgment as to the direction of the sound, but the one feature that was common to all the experiments was that the indicated direction was wrong. Mr. GitBert remarked that the simultaneous occurrence of deto- nations and tremors indicated that the sound waves were identical with some at least of the waves constituting the earthquake. It was therefore legitimate to compare the velocity of transmission of the earthquake waves with the velocity of transmission of sound in vari- ous media, and such comparison indicates that the portion of the crust traversed by the earthquake waves was characterized by an elasticity between that of gold and that of iron. Mr. Bex thought that deductions based upon the assumption that the disturbance had been propagated with the velocity of * The paper was published in extenso in the American Journal of Otology for July, 1880, vol. II, p. 169. See also Nature, vol. X XI, p. 310, and vol. XXII, pp. 586-7. 44 PHILOSOPHICAL SOCIETY OF WASHINGTON. sound should be received with caution; for it is well known that very great and sudden disturbances may be propagated through a medium with a greater velocity than the normal velocity of sound in that medium. In Captain Parry’s Arctic expedition it was noticed that distant observers heard the report of cannon before hearing the command to fire. The PRESIDENT announced that Mr. T. C. MENDENHALL, having removed from the city, had resigned his position on the General Committee of the Society, and that the committee had filled the vacancy by the election of Mr. Wiiu14Mm B. Tayxor. 291st Meerrina. NovEeMBER 6, 1886. Vice-President MALLERY in the Chair. Twenty-three members and guests present. Mr. O. T. Mason made a communication on BOWYERS AND FLETCHERS. [Abstract. ] Whatever may be our theory of creation, the arts of mankind proceed from the same sources as the genera and species of natural objects. The design ‘of this paper is to demonstrate, by means of an art almost universally dispersed in time and place, that we may regard the implements and products of human industry in the light of biological specimens. They may be divided into families, genera, and species. They may be studied in their several ontogenies (that is, we may watch the unfolding of each individual thing from its raw material to its finished production). ‘They may be regarded as the products of specific evolution out of natural objects serving human wants and up to the most delicate machine performing the same function. They may be modified by their relationship, one to another, in sets, outfits, apparatus, just as the insect and flower are co-ordinately transformed. They observe the law of change under environment and geographical distribution. The bow, at first, was only an elastic limb or branch transformed little or none at all. From this parent form have developed three GENERAL MEETING. 45 types under the control of the material, namely, the perfect, simple how, in lands where elastic woods abound; the compound bow, in localities where, by choice or necessity, horn, bone, and antler are preferred as material; and the sinew-backed bow, with its two sub- types of the corded back and the solid back. Each one of these types may be subdivided indefinitely by ethnic marks. The arrow, at first a reed or twig unmodified, was only a shaft with merely an indication of a head as in some of the lower forms. From this, by a normal evolution, have come the feather, fore-shaft, head, and barbs, differentiating into endless varieties under the stress of material, definite functions, and the thousand and one forces which together we may call its environment. A large collection of bows and arrows varying in material, form, and origin was exhibited to exemplify the theory set forth. The communication was discussed by Messrs. Taytor, E. Far- QUHAR, RitEy, Harkness, Dati, and Exxiorr. Mr. Taylor called attention to the break in the evolutionary history of the bow at its very beginning. The stride from the elastic throwing-stick to the bow is immense. The discussion turned chiefly upon the proper basis for museum classification of ethnological material, Messrs. Riley, Dall, and Elliott advocating a classification primarily by peoples or races, and Mr. Mason defending the evolutionary system, where classification by races is supplemented and traversed by a classification in which articles of a kind are placed together. Mr. G. K. Gitprrt began a communication on CERTAIN NEW AND SMALL MOUNTAIN RANGES, which was unfinished when the hour for adjournment arrived. 292p MEETING. NovemMBER 20, 1886. The President in the Chair. Forty-two members and guests present. Mr. G. K. GILBERT completed his communication ON CERTAIN NEW AND SMALL MOUNTAIN RANGES, and remarks were made by Messrs. Brntines and Hazen. 46 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. Tuomas Russevu presented a communication on NORMAL BAROMETERS, which was discussed by Messrs. Brturncs and HARKNEss. Mr. N. H. Darron read a paper ON THE OCCURRENCE OF COPPER ORE IN THE TRIAS OF THE EASTERN UNITED STATES, and Mr. J. S. DitueEr followed with a communication on THE LATEST VOLCANIC ERUPTION IN NORTHERN CALIFORNIA AND ITS PECULIAR LAVA. [Published in Am. Jour. Sci., 3d series, vol. xxxiii.] Remarks on the last paper were made by Mr. Ipp1nes. 2938p MEETING. DrcEeMBER 4, 1886. By courtesy of the trustees of the Columbian University the meet- ing was held in the law lecture-room of the University building. Invitation to attend the meeting was extended to the members of the Anthropological, Biological, and Chemical societies and of the Cusmos Club. ‘Two hundred and two persons were present. Vice-President MALLERY presided. The Chair read a letter from the secretary of the Chemical Society inviting the members of the Philosophical Society to listen, on the evening of Dec. 9, to an address by Prof. H. W. WILEY, retiring president of the Chemical Society, on “ Our Sugar Supply.” President Brituines then presented his annual address, the sub- ject being SCIENTIFIC MEN AND THEIR DUTIES. [Printed in full on pp. Xxxv-Lvi of this volume.] , A vote of thanks for the address was passed by the audience. GENERAL MEETING. 47 2940H MEETING. DECEMBER 18, 1886. THE SIXTEENTH ANNUAL MEETING. The President in the Chair. The minutes of the 292d and 293d meetings were read and ap- proved. . The Chair read the order of business as prescribed by the Stand- ing Rules. The Secretary read the minutes of the fifteenth annual meeting. ' The Chair announced the election to membership of Messrs. JosEePpH CLAYBAUGH GorDon, NeLtson Horatio Darton, MAr- SHALL McDonaup, Witi14mM LEE TRENHOLM, and WILLIAM Francis HILLEBRAND. The annual report of the Secretaries was read. [See page xxrx.] The annual report of the Treasurer was read [see page xxx] and referred to an Auditing Committee, consisting of Messrs. R. 8. Woodward, 8S. M. Burnett, and J. H. Kidder. The Treasurer read the list of members entitled, under Standing Rule 14, to vote for officers. After a recess of five minutes, the Society proceeded to the elec- tion of officers for the year 1887. [The result of the election ap- pears on page Xv. | The following amendment to the Constitution was offered by Mr. W. H. Dall, and laid on the table, as required by Article VI of the Constitution. In Article III insert, after “ consisting of,” the words the ex-prest- dents of the Society. In Article IV insert, before “other members,” the word nine. [The effect of the amendment is to make ex-presidents of the Society permanent members of the General Committee. ] The rough minutes of the meeting were then read, and the Society adjourned. ai Ne ead th yaite ioe iD), \" ta Pe LSE omy te Mae y; ait ye tircantene a 1s f opr re ni re F a ittoed OUT ku! ‘ ; ea Phu wm a aria titgs t ‘7 man é tLaodi hh ¢ ee ncn) Rite Ch fh ; + Neer mkt ak cA vg | f be i pe \ ih An, * t { , 3 ni i} * b * oy = i BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. MATHEMATICAL SECTION. 41 49 STANDING RULES OF THE MATHEMATICAL SECTION. 1. The object of this Section is the consideration and discussion of papers relating to pure or applied mathematics. 2. The special officers of the Section shall be a Chairman and a Secretary, who shall be elected at the first meeting of the Section in each year, and discharge the duties usually attaching to those offices. 3. To bring a paper regularly before the Section it must be sub- mitted to the Standing Committee on Communications for the stated meetings of the Society, with the statement that it is for the Mathematical Section. 4, Meetings shall be called by the Standing Committee on Com- munications whenever the extent or importance of the papers sub- mitted and approved appear to justify it. 5. All members of the Philosophical Society who wish to do so may take part in the meetings of this Section. 6. To every member who shall have notified the Secretary of the General Committee of his desire to receive them, announcements of the meetings of the Sections shall be sent by mail. 7. The Section shall have power to adopt such rules of procedure as it may find expedient. 51 OFFICERS OF THE MATHEMATICAL SECTION FOR 4886. Chairman, Wn. B. Taytor. Secretary, Marcus BAKER. LIST OF MEMBERS WHO RECEIVE ANNOUNCEMENT OF THE ABBE, C. Avery, R.S8. BAKER, M. Bates, H. H. Bixiines, J. S. Burasss, H. §. CurisTiz, A. 8. CorFin, J. H.C. Curtis, G. E. DrLanp, T. L. Doouitrie, M. H. HASTMAN, J. R. EIMBECK, W. ExiottT, E. B. FARQUHAR, H. Fuint, A. S. GILBERT, G. K. Gore, J. H. Green, B. R. Hatt, A. MEETINGS. HArxKNEss, W. Hazpn, H. A. Hit, G. W. Hopextins, H. L. Kine, A. F. A. KumMEL, C. H. Leravour, H. B. McGerz, W J Martin, A. NEWcoB, §. PAUL, El. cite Ritter, W. F. M’K. Ropinson, T. SmiILeEy, C. W. Stone, O. Tayior, W. B. Urton, W. W. Wintock, W. C. Woopwarp, R. 8. ~ ZIWET, A. 52 BULLETIN OF THE MATHEMATICAL SECTION. 22p MEETING. Marcu 24, 1886. The Chairman, Mr. G. W. H1u1, presided. Present, fourteen members and one invited guest. Election of officers of the section for the year 1886 was conducted by ballot, and resulted in the choice of Mr. W. B. Taytor as chair- man and Mr. Marcus BAKER as secretary. Mr. Henry FAarRQuHaAr made a communication on A COMPARISON OF THE BOSS AND AUWERS DECLINATION STANDARDS, in which the systematic difference between the standard of Dr. Auwers’ “ Fundamental-Catalog” and the “ Normal System of Prof. Boss was considered as a function of declination, and shown to be almost completely explained by the supposition of a tube-flexure inadequately allowed for, in the observations on which one or other standard depends. [A paper covering the same ground was afterward read by Mr. FarquuHar before the American Association for the Advancement of Science, and an abstract of it will appear in the proceedings of that body for the Buffalo meeting, 1886. ] . The paper was briefly discussed by Messrs. Hany, Hiuu, and Woopwarp. Mr. R. 8. Woopwarp then read a paper entitled ON THE POSITION AND SHAPE OF THE GEOID AS DEPENDENT ON LOCAL MASSES. [This will be published as a Bulletin of the United States Geo- logical Survey.] na v0 54 PHILOSOPHICAL SOCIETY OF WASHINGTON. 23p MEETING. ApRIL 14, 1886. The Chairman, Mr. Wiii1aAm B. Taytor, elected at the last meeting, presided, and upon taking the chair offered a few remarks expressive of his appreciation of the honor conferred upon him and of his desire for the prosperity of the Section. Present, seventeen members and one guest. Mr. R. S. Woopwarp recited, in abstract, the principal points of his paper of the preceding meeting, and there ensued a general dis- cussion of the subject, in which Messrs. BAKER, DooxiTrie, HILL, Pau, THomAs RussELL, STONE, TAYLOR, aND WOODWARD par- ticipated. Mr. C. H. KumME t then presented a paper ON THE USE OF SOMOFF’S THEOREM FOR EVALUATION OF THE ELLIPTIC INTEGRAL OF THE THIRD SPECIES. [This paper will appear in full in Annals of Mathematics, vol. 2, Nos. 4 and 5.] Remarks were made by Mr. Hu. INDEX. Address of the President...........sssecsseee Administration of research......... Amendment to the constitution............. Nesaaiee American Historical Association, Invitation from the............. 22 Annual Meeting.......cccccccrrseeeeers aedaoswasaitandes Chali; Anthropological Society, Invitation from the 15 Appalachian region, Physical divisions of BUG esac acesses ness “precpenncosnamaeet aicestcneseaseaccnneas 22 Arctic exploration..........ccee+ eoicn 1S Arrow, Development of the 44 Auditing committee, Appointment of... 47 — — Report Off........seseeeesesercnescnssenecrersecseceeees 3 Bates, Newton L.: communication on or- ganic cells of unknown origin and form found in human f@CES..........0sseceeceeeeeceeees 35 — election to membership 37 Bean, T. H.: communication on the sitsets bution of fishes in the oceanic abysses and middle strata (Title).........cssseeceeceeres 22 Bell, A. Graham : remarks on aural determi- nation of the direction of sound........... . 42 — remarks on identity of sound and earth- QUAKC- WAVES... .ccesceesceceesececessens: cneesenenanes 43 Beyer, H. G., Election to membership of...... 37 Bibliography of faults of the Great Basin... 6 Billings, J. S.: annual address as Presi- OM Giovcassscaccecssestvcvsncvecsccercuccensosccsesnee XXxv, 46 — communication on museum specimens PUTS GAGS DIGIOLY.-cne.ccestuacdesccccceesscacecose 35 — remarks on the Charleston earthquake... 42 Bowyers and fletchers........... EOE CRORES ELESCCELULO 44 Bryan, J. H., Election to membership of...... 25 Bulletin, Rules for publication of............ Costas) LAE AGALON OAT ieccecccsecseccnen sre SAacereecbiaccehedtee preeenctes XXViii California, Notes on geology of northern...... + Pols PRODIEMABLIC..s..c.ccccvsvccccccnssessceecccscn sscecs 35 Ceremonial institutiONS.............ceseeeeecseeeeees See) Chamberlin, T. C.: communication on the varying attitudes of former level sur- faces in the Great Lake region and the applicability of proposed explanations \ GILTRE) Vas eR Re ery Beak sccacuvscetes snerenvaqueswccactees 15, 16 Charleston earthquake.........ccsseeeseeee seasserenos OS Chemical Society of Washington, Invitation FLOM THO see eieee ccacsnonevee sesssessessssvecssssssrese 46 | Page. Clarke, F. W.: cited on the relations of Goy- ero i ernment to chemistry... — remarks on problematic cells Committee on communications — — PUDLIcAtiONS..........eeseeceeeeeeeenes peas kVp, == Report) Of AUGITIN GE etic sc:cccsapsccscacsccccenccosses, G —~ Rules of the Peneralwiccvccesccenccnceserasesreven so) XA Comparison of the Boss and Auwers decllna- TION ALANOALOS seccsnceostasersssecesrsrencarmscessve aw, Oe CONS PLGIUGEON oe ccpennteonseutospanenereeestexectdee Constitution, Proposed amendment to........ Se LE Cummings, G. J., Election to membership of 15 Curtice, Cooper, Election to membership of. 87 Curtis, George E.: communication on Lieut. Lockwood’s expedition to farthest north 8 Customs of every day life.............sccsseese esses 19 Dall, W. H.: offers amendment to the con- stitution of the Society......... caaunpapacenenes - 47 — remarks on museum Classification............ 45 Darton, N. H.: communication on the oc- eurrence of copper ore in the Trias of the eastern United States (Title)............ 46 — Election to membership Of..............sssseeeeee 47 Deceased members.......... Declination standards Diller, J. S.: communication on the geology Of Northern! CalifOrnis.. ....1..-ceceecesstwacccene 4,8 — — — — latest volcanic eruption in north- ern California and its peculiar lava (Title) 46 Doolittle, M. H.: remarks on a phonetic alphabet.......... aessnnre Gercase.vcsicensase saaveaner sone 19 Duties of scientific men XXXV Barth Quakes... ..scccecesuccnescas anaes 37, 38 Effects of solar radiation upon iietaneten bulbs having different metallic coverings. 33 HMlection Of OffGOrs..: inc. scccseccscsaccseccustacucsens 47 Elliott, E. B.: communication on the annual profit to banks of national bank note cir- culation (Title)......... Rorbeoteoceetrorseosorbonsin 14 — —— — quantity of United States tanec iary silver coin existing and in circula- TION GD ULLE) scr cvececuscersuresveenancanse Giadaashcnn worse 14 — remarks on museum classification.......... 45 Farquhar, Henry: communication on acom- parison of the Boss and Auwers declina- PLON SEAN ALAS apeasiuscepesteevonsseaensnosaxcsastisy . 63 (55) 56 Page. Farquhar, Henry: communication on a pho- MOC BINED OC cpavecscscacstvavcacvevatecsetersdassns 17 Faults of the Great Basin and Sierra Nevada 65 Fletchers and DOW YeTS...........cssscescssescnecessess General committee, Rules of. — meeting, Minutes Of.....2..ccccccereeeees Sedeneen’ 3 Geology of northern California..........ceceeeeee 4 Gilbert, G. K.: communication on certain new and small mountain ranges (Title)... 45 — — — the observed changes of level sur- faces in the Bonneville area, and their explanation (TZitle)......0. s..ss00 Bedsseches edtee 15 — — — recent changes of level in the basin Of Lake Ontario (Title) ........ ncccsssccecesseen 8 — remarks on geology of Sierra Nevada...... 7 — — — the Charleston earthquake.............. 43 Goode, G. Brown: communication on the dis- tribution of fishes in the oceanic abysses and middle strata (Zitle)......ccessesestssesones 22 ——-— museum specimens illustrating bi- OLO LYS (DRE) ivcckspasenessncssasesnsscatescebanaadeune 36 Gordon, J. C., Election to membership Of...... 4T Governmental administration of research... xlii Great Basin, Faults of the.............sscccssscceees 5 Hall, Asaph: communication on the images Of CHO/StAIS) (CP UL1e) (vesanseurcs exe sossosdsexeesseusn 15 — — — — new Star of Andromeda ( Title)...... 14 Hayden, Everett: communication en the Charleston earthquake............cssssesscsseres 38 Hazen, H. Allen: communication on effects of solar radiation upon thermometer bulbs having different metalliccoverings 33 Hill, R. T., Election to membership of......... 19 Hillebrand, W. F.,Electiontomembershipof 47 Hitchcock, Romyn: communication on re- cent improvements in microscopic ob- jectives, with demonstration of the re- solving power of a new 1-16 inch (Title).. 16 Howland, Dr. E. P.: remarks on the Charles- TOM GALCHQUAKO... se. ccsecessesserencstsscdestrenee 38 Irving, R. D.: communication on the en- largement of mineral fragments as a factor in rock alteration (Title) ............0. 16 — election to Membership.............ceeseeeeeeeeree 16 Institutions, Ceremonial.....,..ccscosseseccrrsssccees 19 Kenaston, C. A., Election to membership of. 16 Kidder, J. H.: communication entitled, his- torical sketch of deep sea temperature QUSOLVALIONS) (CL ULLE) scsscessccicansannaces=ieusadoeer 14 — — — the gilding of thermometer bulbs Kummell, C. H.: communication on the use of Somoff’s theorem for the evaluation of the elliptic integral of the third BDGCIOB ee sccssseceeccers sadetuesseutiandtunseues ‘ - . x a Peli p ql wl i ; * 7 4 \ f 1 A 1 ' r] { : ts N b ‘ yy z ni y " % > sf & t Ni yar 4 ‘ , i“ e* \ 4 ’ ms’ 3 af & < My y a v \ ; iw 4 ‘ f sy ee, pix ‘ i ; : r a 2 4 7 veh r , ‘ ¢ F 4 ot! ; ‘ j ‘ ; ' p ‘ ; i o ‘ + ‘ a \ * a ; : . a ‘i ) f i — é } e. _ i is ' * { U P ‘ + , P | T t ; a iy 7 7 AM: it vr BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. VOL,’ x. 1S87. Containing the Minutes of the Society and of the Mathematical Section for the year 1887; together with the pro- ceedings of the Baird Memorial Meeting AND AN INDEX TO THE FIRST TEN VOLUMES. PUBLISHED BY THE CO-OPERATION OF THE SMITHSONIAN INSTITUTION. WASHINGTON: 1888. ‘ Pm y +) - UD 9 Tew i ate rr a i y ‘i heey + yao’ i oi ih, OEE EE Se ae ae Sn ene) iD BN ES. Page. SEEPS HUCIED IONIC = ees eee Sa erie. eee een ent Oe SAS VILE Branding isles Of the MOGlIeLy ooo aes see ne en oes eee co auee 1 Standing Rules of the/General Committee =—-==- «22 -2eaas 222. XII iulesstor the eublication of the? Bulletins => 2y2 2 ews te see XIII Oficers elected) December 18) 1886 22s Vas OSs eee re see eee XIV Officers elected December 21, DOG hae Ae Os ee a RE EEO | OOK EN estre Cai IVT Fiat Gg A i ee AS ok eh ele ee a Ae XVII Pistiat Wecessed: Members’: 2- 2 ooo 2 5)s- Seis AP Ae eee Ds XXVIII prgmrninry one benship <1 5000 Se 2 ee ek Oe Se ee eo TE RUE NONE Aap Og canes Bees ON ge Cl) oe A ADEN CRE RAMONE DELILE SSR tye. 0 VAN cb Gat AHOUp A ReNOrt.or whetpecretariesues = Lis CEUs Se) Se eee OOLT PeannualsReportior the (reasuren2o2) ete 5 sr ces oe OO ey: Annual Address of the President, William Harkness ---__ -_~_ ___. ORE Bulletin of the General Meetings.____..---___ phe iste SE See 1 Report.of the Auditing Committee 2A ts a 3 Graphic methods in research, G. K. Gilberts-_-. -=__--4-_-— 4 Geologic age of the lowest formation of Emmon’s Taconic sys- tem, C. D. Waleott, (Title only) _....-_.-. ie Ds 5 Present status of mineralogy, F. W. Clarke, (Title ‘only 6 Topography and geology of the cross timbers of Texas, R. T: Hill; (Title onty) =.= =2--_= See oe ea 6 Sky elows of 1883, H. A. Hazen, ‘(Title OTL) eee Ee ek) BN 6 Topography and structure in the Bays Mountains, Tennessee, Bailey Willis, (Pile ory) oS oe eee ee oe fi Geographical distribution of scientific men and institutions in the United States, G. Brown Goode, (Title only) _------ .--- 7 Our city shade trees, their foes and their future, C. V. Riley, (Title COVA) Nae eee DB CE LESS AEDS eka A eM eR a eee 7 Frequency of coincidences, Lester F. Ward_-_-- ---.-----..-- 8 Theory of the wind-vane, G. E. Curtis, (Tvtle only)__-_----_- 9 Electrometer as used in observations of atmospheric electricity, Cale Marvin. (Lecle Oni) eo SaaS oe ae ee ee ete a Development of perspective map from contour map, Bailey Vai ses svt PneLerernbyy 22055 Ste oe ie ee hk ee a a 9 Plane table exhibited and explained, W. D. Johnson -___ -__. 9 Relation between wind velocity and pressure, H. A. Hazen, Tce ratay Meenas Se Rn Eee eee ie ee ee Or ee SA EL 10) Mt. Rainier and its glaciers; Bailey Willis —-..~-...___. 10 What is a topographic map? Marcus Baker ____ ___. 1. 11 Counting-out rhymes of children, H. C. Bolton, (Title only)_- 13 On a device for viewing the sun by light of any desired wave length, William HVarineus 0 tei). eeu) pati fa SA as 13 What is topography? by M. H. Doolittle, W. D. “Johnson, 138i G. Ocden Gilbert "Thompson sos. ste eee SSS Te, TG The Muir elacier, Alaska, J. W. Chickering, (Title only) Mata 15 Economic phase of the English sparrow questicn, C. Hart Morrionn (Petia eny jt ht Pe Ne 16 The quaternary deposits and the great displacement of the middle Atlantic slope, W J McGee, (Pichetordyy ois Se 16 Visit to scene of Charleston earthquake and resulting conclu- sions, ©.) Ey Dution, (tile only) 22-2. ss ee 16 iii IV CONTENTS. South Florida notes, W. H. Dall, (Title only) -------.------- Depth of earthquake foci, C. E. Dutton --__-.--#_--_.---- Manchester meeting of the British Association for the advance- ment of Science, 1887, F. W. Clarke, (Title only) --------- Signal Service bibliography of meteorology, C. Abbe-__-_.-- Geographical distribution of fossil plants, L. F. Ward, (Title OVC) so a ree Re ae a ree Speed * propagation of the Charleston earthquake, C. E. Dutton and Simon Newcomb, (Title only) ----- -----. ---- Representation of comet orbits by models, William Harkness, (Witla ONY) onrn ass Hoan Se) 1 ae eee Statistics of the Philosophical Society, G. K. Gilbert ----___- Newton’s vis, M. H. Doolittle, (Title only) ----- ----------..- Reference indexing, B: Pickman Mann-_-_------. -__ -__- Presentation of the annual. address -.....-.._ _. = se Annual meeting 2.28 cise 22 oe ee Proceedings at the Baird memorial meeting -_-- -_-- -----_ ---. ---.- Introduction 255 2-2-2 oJ es oe he a a Relation of Professor Baird to participating societies, Garrick Mallery s2 222. s)o2/s225 Soa oa ee ee Professor Baird as administrator, Wm. B. Taylor___-__ -_-- Ps Professor Baird in science; Wi. H.. Dall -222 222s eae Personal characteristics of Professor Baird, J. W. Powell-_-- Bulletin‘of ‘the Mathematical Section, 22-223). ee eee Standing rules of the section— .._. —__. . =o eee List of officers and members of the section ..-.-.---. ---___- Association” ratios, MSE. Doolittles-.2 2-22) =o eee The rotten apple problem, a question in probabilities, Marcus Baker, M. H. Doolittle, G.W. Hill, G. E. Curtis, E. B. Elliott, Henry Farquhar, Artemas Martin, Alex. S. Christie, Ormond Stone 2.2. pio ae ee Free cooling of a homogeneous sphere, R. 8. Woodward, (Title Only) q22- 5 tte ee Brachisthode on the helicoid, C. H. Kummell_-_-- ---.---__- Motion of Hyperion, G.. We Hill 22.6.2. co eee Parallax of ¢)'Tauri, Asaph Halls = Most probable value of latitude from entangled observations in use}of Taleott’s method. sAl Ss. Klint 222 eee Mutual action of elements of electric currents, E. B. Elliott__ Association ratios, M.JH.’ Doolittle:22=~ £2. ee eee Solution of a problem in Science, Henry Farquhar, (Title only) Solutions of the trisection problem, Marcus Baker, G. E. Curtis_ Integration of differential equations admitting periodic inte- erals, Gi W.. Hill 2-22 cee oe So oa as cil eo Euler’s theorem (generally called Lambert’s), Asaph Hall.__- New form of computing machine, E. B. Elliott _----. ---__._ The constant P in observations of terrestrial magnetism, Wm, Harkness 25 22s Sees Sans oe ee Conditioned cooling of a homogeneous sphere, R. 8. Woodward- The orbit of Hyperion, Ormond Stone____ -_____ __-- -_...e Quotients of space-directed lines, HE. B. Elliott---__ -___ -__- Methods of finding n** power numbers whose sum is an nth power, Artemas Martin oto.) 22... 5.35 Committees on mathematical communications__-_-__-------- Note on the publications of the Society_-__- .-...-- o_o mr Index to Veluumes IX At 29254 en et eee 96 96, 98 100 101 102 102 103 104 105 107 111 113 117 BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. CONSTITUTION, RULES, LISTS OF OFFICERS AND MEMBERS, CALENDAR, AND REPORTS OF SECRETARIES AND TREASURER. Anite} sine yo wig 4 ae ea ~S CONSTITUTION OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. ArticLE I. The name of this Society shall be Tor PHILOSOPHI- CAL Socrery oF WASHINGTON. ArticuE II. The officers of the Society shall be a President, four Vice-Presidents, a Treasurer, and two Secretaries. ArticuE III. There shall be a General Committee, consisting of the ex-Presidents of the Society, the officers of the Society, and nine other members.* ArticLe IV. The officers of the Society and the nine other mem- bers of the General Committee shall be elected annually by ballot; they shall hold office until their successors are elected, and shall have power to fill vacancies.* ArticLe V. It shall be the duty of the General Committee to make rules for the government of the Society, and to transact all its business. ArticLe VI. This constitution shall not be amended except by a three-fourths vcte of those present at an annual meeting for. the election of officers, and after notice of the proposed change shall have been given in writing at a stated meeting of the Society at least four weeks previously. . * Amended December 21, 1887. : wou Harite i" oy fe ay HOPMAN 8 iv vTating te H Ona ie 21 plein eee my T ad thats ergot aie Re ene nh py RE ab ro ‘55 elie Mf Ass ve. ve » 1 ; b ‘ A ‘ m i * é ‘ ‘Cea igebinw bow ae | Tine elon ates Ne via y Hs a f ‘Abii fir fay ome ans Hays ae Le mie . 2G) ACS aie ; ct ay : bea ante DEOL Kt icp etek honed gtie dk: VOR ah, 8 : Bis bre y ay 3G fs hy EG AMT h Heh ct Laakietirnt abt toons ighG Vit whe pawns iyi) Cab feet ahem Pau y ern eee, Ti Fay er . ed Loar | La eee b poy ¢ z rings cous aay J bs} Kook Bae ¥ OATS Hh. Ae bo Pitt SEATS FS ’ t¥ > Teta 43 te ay a ; 5 fila Po STANDING RULES FOR THE GOVERNMENT OF THE os PHILOSOPHICAL SOCIETY OF WASHINGTON. 1. The Stated Meetings of the Society shall be held at 8 o’clock P. M. on every alternate Saturday; the place of meeting to be designated by the General Committee. 2. Notice of the time and place of meeting shall be sent to each member by one of the Secretaries. When necessary Special Meetings may be called by the President. 3. The Annual Meeting for the election of officers shall be the last stated meeting in the month of December. The order of proceedings (which shall be announced by the Chair) shall be as follows: First, the reading of the minutes of the last Annual Meeting. Second, the presentation of the annual reports of the Secretaries, including the announcement of the names of members elected since the last Annual Meeting. Third, the presentation of the annual report of the Treasurer. Fourth, the announcement of the names of members who, having complied with section 14 of the Standing Rules, are entitled to vote on the election of officers. Fifth, the election of President. Sixth, the election of four Vice-Presidents. Seventh, the election of Treasurer. Eighth, the election of two Secretaries. Ninth, the election of nine members of the General Committee. Tenth, the consideration of Amendments to the Constitution of the Society, if any such shall have been proposed in accordance with Article VI of the Constitution. Eleventh, the reading of the rough minutes of the meeting. 4, * Elections of officers are to be held as follows: In each case nominations shall be made by means of an informal * Amended May 7, 1887. x PHILOSOPHICAL SOCIETY OF WASHINGTON. ballot, the result of which shall be announced by the. Secretary ; after which the first formal ballot shall be taken, In the ballot for Vice-Presidents, Secretaries, and members of the General Committee, each voter shall write on one ballot as many names as there are officers to be elected, viz., four on the first ballot for Vice-Presidents, two on the first for Secretaries, and nine on the first for members of the General. Committee; and on each subse- quent ballot as many names as there are persons yet to be elected ; and those persons who receive a majority of the votes cast shall be declared elected; Provided that the number of persons receiving a majority does not exceed the number of persons to be elected, in which case the vacancies shall be filled by the candidates receiving the highest majorities. If in any case the informal ballot result in giving a majority for any of the candidates, it may be declared formal by a majority vote. 5. The Stated Meetings, with the exception of the Annual Meet- ing, shall be devoted to the consideration and discussion of scientific subjects. The Stated Meeting next preceding the Annual Meeting shall be set apart for the delivery of the President’s Annual Address. 6. Sections representing special branches of science may be formed by the General Committee upon the written recommenda- tion of: twenty members of the Society. 7. Persons interested in science, who are not residents of the Dis- trict of Columbia, may be present at any meeting of the Society, except the Annual Meeting, upon invitation of a member. 8. On request of a member, the President or either uf the Secre- taries may, at his discretion, issue to any person a card of invitation to attend a specified meeting. Five cards of invitation to attend a meeting may be issued in blank to the reader of a paper at that meeting. 9. Invitations to attend during three months the meetings of the Society and participate in the discussion of papers, may, by a vote of nine members of the General Committee, be issued to persons nominated by two members. 10. Communications intended for publication under the auspices of the Society shall be submitted in writing to the General Com- mittee for approval. STANDING RULES. xI 11. Any paper read before a Section may be repeated, either entire or by abstract, before a general meeting of the Society, if such repetition is recommended by the General Committee of the Society. . 12. It is not permitted to report the proceedings of the Society or its Sections for publication, except by authority of the General Committee. 13. *New members may be proposed in writing by three mem- bers of the Society for election by the General Committee ; but no person shall be admitted to the privileges of membership unless he signifies his acceptance thereof in writing, and pays his dues to the Treasurer, within two months after notification of his election. 14. Each member shall pay annually to the Treasurer the sum of five dollars, and no member whose dues are unpaid shall vote at the Annual Meeting for the election of officers, or be entitled to a copy of the Bulletin. In the absence of the Treasurer, the Secretary is authorized to receive the dues of members. The names of those two years in arrears shall be dropped from the list of members. Notice of resignation of membership shall be given in writing to the General Committee through the President or one of the Secre- taries. 15. The fiscal year shall terminate with the Annual Meeting. 16. Any member who is absent from the District of Columbia - for more than twelve consecutive months may be excused from payment of dues during the period of his absence, in which case he will not be entitled to receive announcements of meetings or current numbers ‘of the Bulletin. 17. Any member not in arrears may, by the payment of one hundred dollars at any one time, become a life member, and be relieved from all further annual dues and other assessments. All moneys received in payment of life membership shall be in- vested as portions of a permanent fund, which shall be directed solely to the furtherance of such special scientific work as may be ordered by the General Committee. *Amended Oct. 9, 1886. STANDING: RULES OF THE GENERAL COMMITTEE OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. 1. The President, Vice-Presidents, and Secretaries of the Society shall hold like offices in the General Committee. 2. The President shall have power to call special meetings of the Committee, and to appoint Sub-Committees. 3. The Sub-Committees shall prepare business for the General Committee, and perform such other duties as may be entrusted to them. 4, There shall be two Standing Sub-Committees ; one on Com- munications for the Stated Meetings of the Society, and another on Publications. 5. The General Committee shall meet at half-past seven o’clock on the evening of each Stated Meeting, and by adjournment at other times. 6. For all purposes, except for the amendment of the Standing Rules of the Committee or of the Society, and the election of mem- bers, six members of the Committee shall constitute a quorum. 7. The names of proposed new members recommended in con. formity with Section13 of the Standing Rules of the Society, may be presented at any meeting of the General Committee, but shall lie over for at least four weeks before final action, and the concur- rence of twelve members of the Committee shall be necessary to election. The Secretary of the General Committee shall keep a chronologi- cal register of the elections and acceptances of members. 8. These Standing Rules, and those for the government of the Society, shall be modified only with the consent*of a majority of the members of the General Committee. xii RU OES FOR THE FUBLICATION. OF THE BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. 1. The President’s Annual address shall be published in full. 2. The annual reports of the Secretaries and of the Treasurer shall be published in full. 3. When directed by the General Committee, any communication may be published in full. 4, Abstracts of papers and remarks on the same will be pub- lished, when presented to the Secretary by the author in writing within two weeks of the evening of their delivery, and approved by the Committee on Publications. Brief abstracts prepared by one of the Secretaries and approved by the Committee on Publications may also be published. 5. If the author of any paper read before a Section of the Society desires its publication, either in full or by abstract, it shall be referred to a committee to be appointed as the Section may determine. The report of this committee shall be forwarded to the Publica- tion Committee by the Secretary of the Section, together with any action of the Section taken thereon. 6. Communications which have been published elsewhere, so as to be generally accessible, will appear in the Bulletin by title only, but with a reference to the place of publication, if made known in season to the Committee on Publications. X111 OFRrICHRS OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON ELECTED DECEMBER 18, 1886. President _____ -_-__. WILLIAM HARKNESS. Vice-Presidents __..._.GARRICK MALLERY. C. E. Durron. J. R. EASTMAN. G. K. GILBERT. Treasurer .--- ohatih _ROBERT FLETCHER. Secretaries -.-~ -— ___.Marcus BAKER. J. H. KippeEr. MEMBERS AT LARGE OF THE GENERAL COMMITTEE. H. H. Bartzs. F. W. Ciarxke. W. H. Dat. E. B. Evxiorr. G. B. GoopE. C. V. RILEY. H. M. Pavt. W. C. WINLOCK. R. S. WoopwaRbD. STANDING COMMITTEES. On Communications : J. R. Eastman, Chairman. Marcus BAKER, J. H. Kipper. On Publications: Marcus Baker, Chairman. RoBERT FLETCHER. J. H. Kipper, S. F. Barrp. XIV OP Rt hikes OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON ELECTED DECEMBER 21, 1887. President ..___- --._..GARRICK MALLERY. Vice-Presidents ____J. R. HASTMAN. C. KE. Durron. G. K. GILBERT. G. Brown Goons. Treasurer ....------- ROBERT FLETCHER. Secretaries ....-____.MARCUS BAKER. W. C. WINLOCE. MEMBERS AT LARGE OF THE GENERAL COMMITTEE. H. H. Batzs. F. W. CLarkKE. W. iH. Datu. EK. B. ELwiorr. J. H. K1ipDER. S. P. Lanaiey. He M.PApE: C. V. RILEY: R. S. WooDWARD. PAST PRESIDENTS OF THE SOCIETY AND ex-Orricio MEM- BERS OF THE GENERAL COMMITTEE. J.S. Briirneas, 1886. Simon NeEewcoms, 1879, 1880. AsapH HALL, 1885. J. W. PowE Lt, 1883. Ws. Harxnszss, 1887. W. B. Tayrtor, 1882. J. C. WELLING, 1884. STANDING COMMITTEES. On Communications : G. K. GILBERT, Chairman. J. R. EASTMAN. G. Brown Goopz. On Publications: Marcus Baker, Chairman. RoBERT FLETCHER. W. C. WINLOCK. 5. P. LANGLEY. xv TOO ae erin + . 4 he # y ; 4 Fi J , i. y ‘ wey LP PL retcie ery Fi ‘ f = i ‘ b ? zs Pal : 4 We ° + vi ’ at = ¥ J F ty ] .. N ° : 4 ' ‘ —< ‘ ? 4 Jee é is ey FLAT! PARA Pe : “ lat ae fe ' porte ied Aes : LET 8 ’ "iy ahh WG APS LSet t ~ 5 S ae wh fie hat) Pain, Wel OA a q , r y ig Hig : JASE, ‘ wets } "¥e 4 é é rade “th * pat sy Bae) ake Daret es) yd 4 ® re be ite! } rate ~ ye : < : . y el m7 ah . : ; rae hae nea gd ; 1S» ae ie CE RAAB TE). ru us, - a 4 ri 7 uy “oh Uae &Y is Bes os 8 ‘ i } o otis i ; wt ‘See ilya ee # elo ween ares Z Shape | race dati lath ie wen ; ‘y F ws analvaeek nN | ! © ah Date - ‘ ) " w 5 i hee he << i < * i " ‘ y \ r F i a bail ‘ ral 4 a te 1 Pet 2 nh a mers . on . re Nt my ae a ae Ww PoP en i elie; ith ae RAE Wo ean i Py eS 9 Aa +e tik 5 i , n ~ a ( ft ® ha . * he i ‘ “ ar ae ; ° : 1 : i. k : e : in a Yr 1 f ‘ , ‘ fe } } Y hy ES ol ulin St ast ‘ fe Ne tare. ON » ee LIST OF MEMBERS OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON; TOGETHER WITH YEAR OF ADMISSION TO THE SOCIETY, POST-OFFICE 1871. 1875. 1881. 1873. 1871. 1879. 1887. 1881. 1876. 1875. 1885. 1871. 1886. 1884, ADDRESS, AND RESIDENCE. Corrected to December 31, 1887. ABBE, Prof. Cleveland, Signal Office, War Department. 2017 I street. AseErt, Mr. 8. T. (Sylvanus Thayer) 810 19th street. Apams, Mr. Henry, Auxpis, Hon. A. O. (Asa Owen), 1603 H street. 1765 Mass. avenue. ANTISELL, Dr. Thomas (Founder), Patent Office. 1311 Q street. Avery, Mr. Robert S. (Robert Stanton), BasBcock, ie Wm. H. (William Henry), P. O. Box 220. Baker, Prof. Frank, 320 A street se. 1315 Corcoran street. Baker, Mr. Marcus, Geological Survey. 1125 17th street. Bancrort, George, 1623 H street; in summer, Newport, R. I. Barus, Dr. Carl, Geological Survey. 2750 Q street. Bates, Mr. H. H. (Henry Hobart,) Patent Office. The Portland. Bates, Dr. N. L. (Newton Lemuel), U.S. N., 283 Henry street, Brooklyn, EY Bray, Dr. T. H. (Tarleton Hoffman), National Museum. 1616 19th street XVII XVIII 1875. 1879. 1881. 1871. 1875. 1886. 1871. 1876. 1883. 1884. 1884. 1884. 1883. 1836. 1883. 1879. 1874. 1871. 1882. 1883. 1885. 1874. 1880. PHILOSOPHICAL SOCIETY OF WASHINGTON. BEARDSLEE, Capt. L. A. (Lester Anthony), U.S. N. (At Little Falls, N. Y Betz, Mr. A. Graham (Alexander Graham), 1336 19th street. Bex, Dr. C. A. (Chichester Alexander) (Absent), University College. London, England. Benet, Gen. S. V. (Stephen Vincent), U. 8. A. (Founder), Ordnance Office, War Dept. 1717 I street. BessExs, Dr. Emil, Glenn Dale, Md. Bryer, Dr. H. G. (Henry Gustav) (Absent), Navy Department. Bruines, Dr. John §. (John Shaw), U.S. A. (Founder), Army Medical Museum. 3027 N street. Brrnig, Capt. Rogers, Jr., U. S. A Office Chief of Ordnance, u; S.A. 1341 N. H. avenue. Boprisy, Mr. 8. H. (Sumner Homer), Geological Survey. 807 H street. BouTE..E, Capt. C. O. (Charles Otis), ‘Coast and Geodetic Survey. Bow tes, Asst. Nav. Constr. Francis T. (Francis Tiffany), U.S. N. (Absent), Navy Department. Brown, Prof. S. J. (Stimson Joseph), U.S. N. (Absa Washburn Observatory. Madison, Wis. Browne, Dr. J. Mills (John Mills), U.S. N., Navy Department. The Portland. Bryan, Dr. J. H. (Joseph Hammond), 1644 Connecticut avenue. Bureess, Mr. E. S. (Edward Sandford), High School. 1120 18th street. Burnett, Dr. Swan M. (Swan Moses), 1734 K street. Busey, Dr. Samuel C. (Samuel Clagett), 901 16th street, Casey, Col. Thomas Lincoln, U. 8. A. (Founder, absent), Army Building, cor. Green and Houston Sts., New York city. Cazrarc, Lieut. L. V. (Louis Vasmer), U.S. A. (Absent), Fortress Monroe, Va. CHAMBERLIN, Pres. T. C. (Thomas Crowder) (Absent), Madison, Wis. CuararD, Dr. Thomas M. (Thomas Marean), Geological Survey. Cosmos Club. CuicKERING, Prof. J. W., Jr. (John White), Deaf Mute College, Kendall Green. Curistiz, Mr. Alex. S. (Alexander Smyth), Coast and Geodetic Survey. 204 4th street se. ~ 1877. 1874. 1871. 1880. 1874. 1873. 1879. 1886. 1886. 1884. 1871. 1886. 1880. 1872. 1881. 1884. 1884. 1876. 1873. 1872. 1884. 1871. 1884. LIST OF MEMBERS. XIX CuarK, Mr. Edward, Architect’s Office, Capitol. 417 4th street. CLARKE, Prof. F. W. (Frank Wigglesworth), Geological Survey. 1425 Q street. CorFin, Prof. J. H. C. (John Huntington Crane), U.S. N. (Founder), 1901 I street. Comstock, Prof. J. H. (John Henry) (Absent), Cornell University, Ithaca, N. Y. Cougs, Prof. Elliott, Smithsonian Institution. 1726 N street. Crate, Lieut. Robert, U. 8. A. (Absent), ar Department. Craic, Dr. Thomas (Absent), Johns Hopkins University, Baltimore, Md. CUMMINGS, Prof. G. J. (George Jotham), Howard University. Curticg, Dr. Cooper, Agricultural Department. Curtis, Mr. Geo. E. (George Edward) (Absent), Washburn College, Topeka, Kansas. Datu, Mr. Wm. H. (William Healey) (Founder), Smithsonian Institution. 1119 12th street. Darton, Mr. N. H. (Nelson Horatio), Geological Survey. 1412 N street. Davis, Commander C. H. (Charles Henry), U.S. N., Navy Department. Dean, Dr. R. C. (Richard Crain), U.S. N. (Absent), Navy Department. 45 Lafayette Place, N. Y. city. De Carnpry, Mr. Wm. A. (William Augustin), War Department. 1014 17th street. Dewey, Mr. Fred. P. (Frederic Perkins), National Museum. Lanier Heights. Ditter, Mr. J. S. (Joseph Silas), Geological Survey. 1804 16th street. Doouittiez, Mr. M. H. (Myrick Hascall), Coast and Geodetic Survey. 1925 I street. Dunwoopy, Lt. H. H. C. (Henry Harrison Chase), U.S. A. (Absent), War Department. Dutton, Capt. C. E. (Clarence Edward), U.S. A Geological Survey. 2119 I street. Ear, Mr. R. Edward (Robert Edward), National Museum. 1536 T street. EASTMAN, Fret J. R. (John Robie), U.S. N., Naval Observatory. 1905 N street. Ermseck, Mr. William, - Coast and Geodetic Survey. xx 1871. 1871. 1885. 1873. 1874. 1876. 1881. 1887. 1872. 1873. 1882. 1881. 1873 1875. 1874. 1875. 1879. 1885. 1874. 1875. 1886. 1880. 1878. 1839. PHILOSOPHICAL SOCIETY OF WASHINGTON. ELpRreEDGE, Dr. Stewart (Absent), Yokohama, Japan. Exxiort, Mr. E. B. (Ezekiel Brown) (Founder), Gov’t Actuary, Treas. Dept. 1210 G street. Emmons, Mr. 8. F. (Samuel Franklin), Geological Survey. 1708 H street. Enputcu, Dr. F. M. (Frederic Miller) (Absent), Reading, Pa. Ewina, Gen. Hugh (Absent), Lancaster, Ohio. Farquuar, Mr. Edward, Patent Office Library. 1915 H street. Farquuar, Mr. Henry, Coast and Geodetic Survey. Brooks Station, D. C. Fernow, Mr. B. E. (Bernhard Eduard), Department of Agriculture. Cor. 8th and B streets sw. FrErRREL, Prof. William, 1641 Broadway, Kansas City, Mo. FLEetTcHeER, Dr. Robert, Army Medical Museum. The Portland. Fuiint, Mr. A. S. (Albert Stowell), Naval Observatory. 1441 Chapin street. Fiint, Dr. J. M. (James Milton), U.S. N., Smithsonian Institution. The Portland. . Friston, Prof. Edward T, Columbian Oniversity, cor. 15th and H streets. GALLAUDET, President E. M. (Edward Miner), Deaf Mute College, Kendall Green. Gannett, Mr. Henry, GeologicalSurvey. 1881 Harewood ave., LeDroit Park. GitBert, Mr. G. K. (Grove Karl), Geological Survey. 1424 Corcoran street. Goppina, Dr. W. W. (William Whitney), Government Hospital for the Insane. Goocnu, Dr. F. A. (Frank Austin) (Absent), Yale College, New Haven, Connecticut. Goops, Mr. G. Brown (George Brown), Smithsonian Institution, 1203 N. H. ave. GoopFreEeLLow, Mr. Edward, Coast and Geodetic Survey. Gorpov, Prof. J. C. (Joseph Claybaugh), Deaf Mute College, Kendall Green. Gore, Prof. J. H. (James Howard), Columbian University. 1305 Q street. Graves, Mr. Walter H. (Walter Hayden) (Adsent), Denver, Colorado. Greevy, Gen. A. W. (Adolphus Washington), U.S. A., Signal Office, War Department. 1914 G street. 1879. 1875. 1871. 1875. 1884. 1879. 1879. 1871. 1884. 1885. 1885. 1871. 1880. 1886. 1882. 1884. 1874. 1879. 1886. 1886. 1884. 1885. LIST OF MEMBERS. XXI GREEN, Mr. Bernard R. (Bernard Richardson), Office of Building for State, War, and Navy Departments. 1788 N street. GREEN, Commander F. M. (Francis Mathews), U. S. N. (Absent), Navy Department. GREENE, Prof. B. F. (Benjamin Franklin), U. 8. N. (Pounder, absent), ‘ West Lebanon, N. H. GREENE, Francis V. Crbaiye ores Vinton) (Absent), No. 1, Broadway, New York city. Grucory, Dr. J. M. (John Milton) (Absent), 45 Albert st., Regent’s Park, London, England. GUNNELL, Surg. Gen’l F. M. (Francis M.), U.S. N.,. Navy Department. 600 20th street. Hains, Lt.-Col. P. C. (Peter Conover), U.S. A., Engineer’s Office, Potomac River Improve- ment, 2136 Pa. ave. 1824 Jefferson place. Hatt, Prof. Asaph, U. 8. N. (Founder), Naval Observatory. 2715 N street. Hatt, Mr. Asaph, Jr. (Absent), Yale Observatory, New Haven, Conn. Hauuock, Dr. William, Geological Survey. 29234 M street. Hampson, Mr. Thomas, Geological Survey. Lanier avenue. Harkness, Prof. William, U. 8. N. (Founder), Naval Observatory. Cosmos Club. Hasster, Dr. F. A. ye Augustus) (Absent), Santa Afia, Los Angeles Co., Cal. Haypen, Lieut. Everett, U. 8S. N., Hydrographic Office. Hazen, Prof. H. A. (Henry ‘Allen), P. O. Box 427. 1416 Corcoran street. Heap, Major D. P. (David Porter), U. 8. A. (Resigned), Engineer 3d and 4th Light House District, Tompkins- ville, N. Y. Hensnaw, Mr. H. W. (Henry Wetherbee), Bureau of Ethnology. 13 Lowa Circle. Hix, Mr. G. W. (George William), Nautical Almanac Office. 314 Indiana ave. Hi, Mr. R. T. (Robert Thomas), Geological Survey. 1626 15th street. HiLLeBranp, Dr. W. F. (William Francis), Geological Survey.’ 506 Maple ave., Le Droit Park. Hirexncock, Mr. Romyn, National Museum. Osaka, Japan. Hopexrns, Prof. H. L. (Howard Lincoln), Columbian University. 1532 19th street. ‘4 XXII 1873. 1887. 1879, i874. 1885. 1886. 1880. 1871. 1878. 1879. 1884. 1873. 1884. 1886. 1884. 1880. 1880. 1875. 1887. 1887. 1874. 1887. 1882. PHILOSOPHICAL SOCIETY OF WASHINGTON, Ho.pen, Prof. E. S. (Edward Singleton) (Absent), Lick Observatory, San José, Cal. Houmes, Mr. J. H. (Jesse Herman), 1811 I street. Ho.mes, Mr. W. H. (William Henry), Geological Survey. 1444 Stoughton street. Howe t, Mr. E. E. (Edwin pres (Absent), 8 Oxford street, Rochester, NUYS Ipprnes, Mr. J. P. (Joseph pany: Geological Survey. 1028 Vermont ave. Irvine, Prof. R. D. (Roland Duer), Geological Survey. Madison, Wis. James, Rev. Owen (Absent), Scranton, Pa. Jenkins, Rear Admiral T. A. (Thornton Alexander),U.S.N. (Founder), 2115 Pennsylvania ave. Jounson, Mr. A. B. (Arnold Burges), Light House Board, Treas. Dept. 501 Maple ave., Le Droit Park. Jounson, Dr. Joseph Taber, Private Hospital, 1728 K street. Jounson, Mr. Willard D. (Willard Drake), Geological Survey. 501 Maple ave., Le Droit Park. Jounston, Dr. W. W. (William Waring), KaurrMany, Mr. 8. H. (Samuel Hay), 1603 K street. 1000 M street. Kewnaston, Prof. C. A. (Carlos Albert), Howard University. Kerr, Mr. Mark B. (Mark Brickell), Geological Survey. 2104 H street. Kipper, Dr. J. H. (Jerome Henry), ; Smithsonian Institution. 1606 N. H. ave. Kiizpourne, Lieut. C. E. (Charles Evans), U.S. A. (Absent), War Department. Kine, Dr. A. F. A. (Albert Freeman Africanus), 726 13th street. Kine, Mr. Harry, Geological Survey. 1319 Q street. Knicur, Mr. Fred J. (Fred Jay), Geological Survey. Knox, Hon. John Jay (Absent), Prest. Nat. Bank Republic, New York city. -19 E. 41st street. Know toy, Mr. F. H. (Frank Hall), National Museum. 202 Sth street se. KumMELL, Mr. C. H. (Charles Hugo), Coast and Geodetic Survey. 608 Q street. 1887. 1884. - 1874. 1882. 1871. 1880. 1886. 1886. 1883. 1879. 1876. 1884. 1875. 1885. 1886. 1885. 1878. 1875. 1884. 1871. 1885. 1886. 1884. 1886. LIST OF MEMBERS. XXIII LaAnGctLey, Prof. S. P. (Samuel Pierpont), Secretary Smithsonian Institution. LAWRENCE, Mr. William, Leg, Dr. William, 2111 Penna. ave. 1821 I street. Leravour, Mr. E. B. (Edward Brown) (Absent), Cambridge, Mass. Lincotn, Dr. N. 8. (Nathan Smith), Loomis, Mr. E. J. (Eben Jenks), Nautical Almanac Office. 1443 Stoughton street. McAprz, Mr. A. G. (Alexander George), U.S. Signal Office, St. Paul, Minn. McDona.p, Col. Marshall, U. 8. Fish Commission. 1515 R street. McGekg, Mr. W J, Geological Survey. McGurrg, Mr. Fred. B. (Frederick Bauders), 1416 F street. 614 E street. McMortrig, Prof. William (Absent), University of Illinois, Champaign, Ill. Mauer, Mr. James A. (James Arran), Bellefontaine, Ohio. 1514 H street. Geological Survey. 15 Grant Place. Ma.uery, Col. Garrick, U.S. A., Bureau of Ethnology. 1323 N street. Many, Mr. B: Pickman (Benjamin Pickman), Patent Office. 1918 Sunderland Place. Martin, Mr. Artemas, Coast and Geodetic Survey. 55 C street se. Marvin, Prof. C. F. (Charles Frederick), Signal Office, War Department. 1786 13th street. Marvin, Mr. Jos. B. (Joseph Badger), Lock Box 379. Mason, Prof. O. T. (Otis Tufton), . National Museum. 1305 Q street. Matruews, Dr. W. (Washington), U.S. A., Army Medical Museum. 1262 New Hampshire ave. Metcs, Gen. M. C. (Montgomery Cunningham), U. S. A. (Founder), 1289 Vermont avenue. MENDENHALL, Prof. T. C. (Thomas Corwin) (Absent), Terre Haute, Ind. Merriam, Dr. C. Hart (Clinton Hart), Department of Agriculture. 1919 16th street. MERRILL, Mr. George P. (George Perkins), National Museum. 1602 19th street. MircHELL, Prof. Henry, 43 Coast and Geodetic Survey. 1331 L street. XXIV. 1883. 1885. 1884. 1881. 1871. 1872. 1871. 1879. 1884. 1885. 1884. 1878. 1871. 1871. 1871. 1877. 1874. 1873. 1884. 1882. 1874. 1880. 1879. PHILOSOPHICAL SOCIETY OF WASHINGTON. Moraan, Dr. E. Carroll (Ethelbert Carroll), : 918 E street. Moser, Lieut. J. F. (Jefferson Franklin), U. 8S. N. (Absent), Navy Department. Murpoca, Mr. John, ; Smithsonian Institution. 1429 Stoughton street. MusseEy, Gen. R. D. (Reuben Delavan), P. O. Box 618. NEwcoMB, Baik Simon, U.S. N. (Founder), Navy Department. Nicwots, Dr. C. H. (Charles Henry) (Absent), Bloomingdale Asylum, Boulevard and 117th street, New York city, N. Y. Nicuotson, Mr. W. L. (Walter Lamb) (Founder), 2222 G street. Norpuorr, Mr. Charles, 1732 H street. Norris, Dr. Basil, U. 8. A. (Absent), Vancouver Barracks, Wash. Ter. Nort, Judge C. C. (Charles Cooper), Court of Claims. 826 Connecticut ave. Oapen, Mr. H. G. (Herbert Gouverneur), Coast and Geodetic Survey. 1324 19th street. OsBoRNE, Mr. J. W. (John Walter), 212 Delaware ave ne. Parke, Gen. John G. (John Grubb), U.S. A. (Founder), West Point, N. Y. ParRKER, Dr. Peter (died Jan. 10, 1888) (Founder), Parry, Dr. C. C. (Charles Christopher) (Absent), Davenport, Iowa. Paut, Mr. H. M. (Henry Martyn), Naval Observatory. 1915 G street. PEALE, Dr. A. C. (Albert Charles), Geological Survey. 1446 Stoughton street. Por, Gen. O. M. (Orlando Metcalfe), U.S. A. (Absent), West Congress street, Detroit, Mick. PorInDEXTER, Mr. W. M. (William Mundy), 1505 Pennsylvania ave. 1227 15th street. Pope, Dr. B. F. (Benjamin Beare a S. A. (Absent), Surg. General’s Office, U. Powe tL, Major J. W. (John Walley), Geological Survey. 910 M street. Prentiss, Dr. D. W. (Daniel Webster), 1101 14th street. PritcHert, Prof. H. 8. (Henry Smith) (Absent), Director of Observatory, Washington University, St. Louis, Mo. 1882. 1884. 1883. 1884. 1878. 1879. 1884, 1872. 1882. 1883. 1883. 1883. 1871. 1871. 1887. 1875. 1874, 1881. 1879. 1883. 1882. 1876. LIST OF MEMBERS. XXV RatuBuy, Mr. Richard, National Museum.. 1622 Massachusetts ave. Ray, Lieut. P. H, (Patrick Henry), U.S. A., Fort Gaston, Cal. RensHAWE, Mr. Jno. H. (John Henry), Geological Survey. 1215 L street. RicKsEcKER, Mr. Eugene, Geological Survey. 904 14th street. Riuey, Dr. C. V. (Charles Valentine), Department of Agriculture. 1700 13th street. Ritter, Mr. W. F. McK. (William Francis McKnight) (Absent), P. O. Box 50, Milton, Pa. Rosrnson, Mr. Thomas, U.S. Engineer Service. * Vienna, Va. Rogers, Mr. Joseph A. (Joseph Addison) (Absent), Naval Observatory. Russet, Mr. Israel C. (Israel Cook), Geological Survey. 42 B street ne. RussEtuL, Mr. Thomas, Sigual Office, War Department. 1344 Wallach Place. Saumon, Dr. D. E. (Daniel Elmer), Agricultural Department. 1716 13th street. Sampson, Commander W. T. (William Thomas), U.S. N. (Absent), Naval Academy, Annapolis, Md. Saviuue, Mr. J. H. (James Hamilton), 1419 F street. 1315 M street. Scnort, Mr. Charles A. (Charles Anthony) (Founder), Coast and Geodetic Survey. 212 Ist street se. Srety, Col. F. A. (Franklin Austin), Patent Office. SHELLABARGER, Hon. Samuel, Room 31 Kellogg Building. 812 17th street. SHERMAN, Hon. John, U.S. Senate. 1319 K street. SHUFELDT, Dr. R. W. (Robert Wilson), U. S. A. (Adsent), Care Smithsonian Institution. SiasBEE, Commander C. D. (Charles Dwight), U. S. N (Absent), Naval Academy, Annapolis, Md. Sxrinner, Dr. J. O. (John Oscar), Ue S. A. (Absent), Surg. General’s Office, U. S. Smitey, Mr. Chas. W. (Charles Weales), U.S. Fish Commission. 943 Massachusets ave. Smiru, Chf. Eng. David, U.S. N., Navy Department. XXVI 1880. 1887. 1886. 1887. 1872. 1884. 1874. 1887. 1881. 1871. 1875. 1884. 1878. 1873. 1886. 1882. 1882. 1880. 1883. 1881. 1872. 1883. 1876. PHILOSOPHICAL SOCIETY OF WASHINGTON. Samira, Mr. Edwin, Coast and Geodetic Survey. 2024 Hillyer Place. Smytu, Mr. H. L. (Henry Lloyd), Geological Survey. Sneux, Mr. Merwin M. (Merwin-Marie), National Museum. 732 6th street. Spencer, Dr. J. W. (Joseph William), 1012 17th street. Sporrorp, Mr. A. R. (Ainsworth Rand), Library of Congress. 1621 Massachusetts ave. Srrarns, Mr. R. E. C. (Robert Edwards Carter), Geol. Survey; Smithsonian Institution. 1213 12th St. Srong, Prof. Ormond (Absent), Leander McCormick Observatory, Univ. of Virginia. Symons, Capt. T. W. (Thomas William), U. S. A., District Building. 1727 De Sales street. Tay or, Mr. F. W. (Frederick William) (Absent), Smithsonian Institution. Tay or, Mr. William B. (William Bower) (Founder), Smithsonian Institution. 306 C street. Tuompson, Prof. A. H. (Almon Harris), Geological Survey. Tuompson, Mr. Gilbert, Geological Survey. 1448 Q street. Topp, Prof. David P. (David Peck) (Absent), Amherst College Observatory, Amherst, Mass. Toner, Dr. J. M, (Joseph Meredith), 615 Louisiana ave. Trenuoim, Hon. W. L. (William Lee), Comptroller of the Currency. 1815 M street. True, Mr. F. W. (Frederick William), National Museum. 1101 14th street. Upton, Mr. Wm. W. (William Wirt), 1416 F street. 1746 M street. Upton, Prof. Winslow (Absent), Brown University, Providence, R. I. Wat corr, Mr. C. D. (Charles Doolittle), Geological Survey ; National Museum. Wa.po, Prof. Frank (Absent), Forest ave., Cincinnati, Ohio. WALKER, Mr. F. A. (Francis Amasa) (Atsoay Massachusetts Institute of Technology, Boston, Mass. Wane, Mr. H. F. (Henry Francis) (Absent), Mass. Trigonometrical Survey, Cambridge, Mass. Warp, Mr. Lester F. (Lester Frank), . Geological Survey. 1464 Rhode Island ave. — ee 1882. 1885. 1882. 1873. 1876. 1884. 1887. 1885. 1887. 1885. 1875. 1880. 1875. 1871. 1883. 1885. 1885. 1887. 1874, 1884. 1885. LIST OF MEMBERS. XXVII Wesster, Mr. A. L. (Albert Lowry) (Absent), 107 Drexel Building, Broad street, New York city; West New Brighton, Staten Island, N. Y. WEED, Mr. W. H. (Walter Harvey), Geological Survey. 825 Vermont ave. Wetting, Mr. J. C. (James Clarke), 1302 Connecticut ave. WHEELER, Capt. Geo. M. (George Montague), U.S. A., Lock Box 93. 930 16th street. Wuirte, Dr. C. A. (Charles Abiathar), Geological Survey. 3812 Maple ave., Le Droit Park. Wuirte, Dr. C. H. (Charles Henry), U.S. N., Museum of Hygiene. Wairine, Mr. H. L. (Henry Laurens), Coast and Geodetic Survey. West Tisbury, Mass. Wixuis, Mr. Bailey, Geological Survey. 1739 G street. Wixson, Mr. H. C. (Herbert Couper) (Absent), Carleton College Observatory, Northfield, Minn. Witson, Mr, H. M. (Herbert Michael), Geological Survey. 1715 G street. Witson, Mr. J. Ormond (James Ormond), 1439 Massachusetts ave. Wintock, Mr. W. C. (William Crawford), Naval Observatory. 1923 H street. Woop, Mr. Joseph (Absent), Pittsburgh, Penn. Woop, Lieut. W. M. (William Maxwell), U.S. N. (Adsent), Navy Department. Woopwarp, Mr. R. S. (Robert Simpson), Geological Survey. 1804 Columbia road. WortmMan, Dr. J. L. (Jacob Lawson), Army Medical Museum. 1711 13th street. Wricut, Mr. Geo. M. (George Mitchell) (Absent), Akron, Ohio. Woirvemany, Mr. H. V. (Harry Vanderbilt), Geological Survey. 12353 5th street. Yarrow, Dr. H. C. (Harry Crécy), Army Medical Museum. 814 17th street. Yeates, Mr. W.S. (William Smith), Smithsonian Institution. 631 T street. ZiwEt, Mr. Alexander, 64 Sibley street, Detroit, Mich. XXVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. LIST OF DECEASED MEMBERS. Name. Benjamin Alvord Orville Elias Babcock Theodorus Bailey Spencer Fullerton Baird Joseph K. Barnes Henry Wayne Blair Horace Capron Salmon Portland Chase . Frederick Collins Benjamin Faneuil Craig Charles Henry Crane Josiah Curtis Richard Dominicus Cutts Charles Henry Davis Frederick William Dorr Alexander B. Dyer Amos Beebe Eaton . Charles Ewing Elisha Foote . John Gray Foster Leonard Dunnell Gale Isaiah Hanscom . William Babcock Hecani Joseph Henry Franklin Benjamin wee! Andrew Atkinson Humphreys . Ferdinand Kampf : Washington Caruthers Kerr Jonathan Homer Lane Edward Phelps Lull Oscar A. Mack Archibald Robertson Mavving 4 Fielding Bradford Meek James William Milner . Albert James Myer George Alexander Otis . Peter Parker. Carlile Pollock Patterson Titian Ramsay Peale Benjamin Peirce John Campbell Riley John Rodgers Admitted. « P1872 1871 F 1873 Founder Founder 1884 Founder Founder 1879 Founder Founder 1874 1871 1874 1874 Founder Founder 1874 Founder 18738 1874 1873 : 1881 Founder ‘ 1879 Founder 1875 1883 Founder 1875 1872 1874 Founder 1874 Founder Founder Founder 1871 Founder Founder 1877 1872 LIST OF MEMBERS. XXIX Name. Admitted, Benjamin Franklin Sands . : : . . . Founder George Christian Shaeffer ‘ : ‘ : : Founder Henry Robinson Searle ‘ ; : : : Pl guna 8 2 G4 William J. Twining . F : : : : 1878 Joseph Janvier Woodward . : ‘ . ° . Founder John Maynard Woodworth . : m . 1874 Mordecai Yarnall_ . A : , a diy ato l SUMMARY. Active members 4 : : x : 182 Absent members . : : : : : 58 Total . : : - “ ° 240 Deceased members. : : . . - 49 mi. Great Neat AS ie LS een ‘ vi ay Me Gia onan? NG Mn elas ks Rf dp uv dere hoayys bing ‘ fe ; t pr FES SNe ee, Ps ax Ck Ply eR “Wt taetar ae . MLA Ricoto Baal ge rs | ada Diane ' J Ny a fs { ny * . yt 1 oki ‘ 1 Pua t A “ } are ; ' 7 a: : . 7 . ! ir y : ‘ ! ‘ ( / ' j : } ‘ tH ; ' j } é@ : e it Me > i ’ wal . \ ; . mh R : 4 7 ' i ve \ F ‘ i if : 4 Ay fs Pa " ' , , A ‘ \ J 1 i ee Ko y ‘ i . . 4) Pa ‘3 . = \ i r 15 {8,4 ‘ , “ T ’ y a f i a) \ aay \ Pa aX 1 4 Pari x jilaal , ay . > , ( * r ‘ i) < i it : i. i i ee) a # t he / LK ‘ ii rs ; j tee me t; fa : i \ WS } : i < ¥ x . ¢ ¥ 8) hi . ‘ “ Tihs i i * in wo XXXI PHILOSOPHICAL SOCIETY OF WASHINGTON. 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See eee LOGT: Soar = sH an sereeeeeeeeeogoy raeewossneeeg coy - - O2rowo = 1 i~] N eon ae get nag) = Coods R =x = “LOQUIQAON | *19q0}00 “sIGIA “poystiqnd porzspso pur “bggr ‘4 aunf aaywu0g yerauax) ay) 0} peyiuqns “LLOITIY "g “G ‘YU Ad aauvaaug *aaesiniz ‘90, -Lobr 03 $9 -t 931 Ulf ., SUOSDAS 5, JDAARAIS ay Stttanp ssuroayy Sumpjoy 4of SA VALOLVS %wvusayo yz Suummys ‘ALYIOOS IVOIHdOSOTIHA HHL FO USN AHL YOL UVGNATVO XXXII PHILOSOPHICAL SOCIETY OF WASHINGTON. ANNUAL REPORT OF THE SECRETARIES. WasuHinoton, D. C., December 21, 1887. To the Philosophical Society of Washington : We have the honor to present the following statistical data for “paper: The last Annual Report brought the record of membership down to December 18, 1886. The number of active mem- bers was then . . ; , ° ‘ , . « 283 shis number has been increased by the addition of 14 new members, by the return of 1 absent member, and by the reinstatement of 2 members previously dropped. It has been diminished by the departure of 7 members, by the resignation of 1, and by the death of 3 members. The net increase of active members has thus been : é ‘ 6 And the active membership is now. : : : Be The roll of new members is: W. H. Bascocr. F. H. Know.rTon. T. W. Symons EvEerReTr HAYDEN. S. P. Lanaury. H. L. WHITING J. H. Hotmzs. F. A. SEELY. H. C. WiLson Harry Kina. H. L. Smyru. H. V. WtUrDEMAN. F. J. Knieur. J. W. SPENCER. The roll of deceased members is: S. F. Barrp. W. B. Hazen. E. P. Luu. There have been 16 meetings, of which 14 have been for the pre- sentation and discussion of papers, 1 for the President’s Annual Address, and 1 for the Annual Reports and election of officers ; the average attendance (at the 14 meetings for presentation of papers), has been 49. There have been 12 meetings of the Mathe- matical Section; average attendance 17. The first 5 meetings of the year were held in the library of the Surgeon General’s Office, at which meetings the average attendance was 40; the 9 remaining meetings were held in the Assembly Hall of the Cosmos Club, at which the average attendance was 54. In the general meetings 37 communications have been presented ; in the Mathematical Section 20. Altogether 57 communications SECRETARIES’ REPORT. XXXIII have been made by 37 members and 1 guest. The number of members and guests who have participated in the discussions is 40. The total number who have contributed to the scientific proceed- ings is 47, or 25 per cent. of the present active membership. The General Committee has held 16 meetings; average attend- ance 13, the smallest attendance at any meeting being 11 and the largest 15. Of the present active membership 146, or 77 per cent., are em- ployed in the service of the Government, and 44, or 23 per cent., are not so employed. Marcus BAKER, J. H. Kipper, Secretaries. XXXIV PHILOSOPHICAL SOCIETY OF WASHINGTON. REPORT OF THE TREASURER. Mr. President and Gentlemen: The report which I shall presently have the honor to submit to you exhibits the total receipts and disbursements for the fiscal year ending with this meeting. The receipts, however, include amounts received for outstanding dues of previous years, and it is, therefore, proper to say that the income belonging to the year 1887 was $1,035.75, and the expendi- ture $568.22, leaving a net surplus for the year of $467.53. The unpaid dues of former years which have been collected in 1887 amount to $120. The assets of the Society consist of: 2 Government bonds, $1,000 and $500, at 4 per cent., $1,500 00 1 : bond, 1,000, ab hay 1,000 00 6 Cosmos Club mortgage bonds, cae ae 600 00 Cash with Riggs & Co. : ; : : : : 942 05 Wapaid dues. oa ie) Oia tea ee a 265 00 Total . : : ; : : J . $4,307 05 The removal of the Society from its old place of meeting at the Army Medical Museum made it nececessary to provide certain articles of furniture and equipment for use in its new quarters. The ninth volume of the Bulletin was duly issued in January to all members entitled to receive it, and to the societies and scientific journals with which it is customary for the Philosophical Society to exchange publications. XXXV TREASURER’S REPORT. ‘wainsna4y, “THHOLATA LAIAAOW ee ee ee, oe 1% 1ea‘T$ IF peed paint ea ee aonmaas === -=== or 99 SSSIYT [IM OOUBleg ere aIn}UINJ 19q}0 pus ‘ysop sul -pvor ‘9[qe} ‘pavoq-yov[q 10; pred yseo Ag (Sie a ae es *-oyo ‘ort yaoro ‘Arou0ry -vys ‘osvysod 10f solieja100g puB JdINSBOL, jo sosuedxe snosuvyjoosiu roy pred yseo Ag Sea ‘oqo ‘srvpnoi1o ‘sprvo [eysod —Suryurd snoouspeostut soy pred ysvo Ag =a ee “Saou .[Molteuie -YIV]T oY} Jo pus ‘Ayo100g oy} Jo ssutyoour uo sourpusyze sof sdoytuvl pred yseo Ag "1% ‘00d Adee apa ae Bees pee: urjolIng oy} JO XT ‘OA Suiddeim pur ‘Surpurq ‘sur -yurd s0j JoplomMyoq ® ppne pred yseo Ag -g ‘qoq “L881 "1881 ‘IZ vaquacagq ‘NOLONIHSV MA 1% 129't 00-S81.= = oS GS OO GP mi » FIV 000'T » 00 09$ ~~~777 "~~" "yueo sod F 48 OOG‘TS UO : Spuoq UO 4so19JUL IOJ * i 00 006 00 GI ~"888T ” ” ” 00 G9L ~~ L881 ” ” ” 00 OOT ~"988T ” ” ” 00 02% ~~G881 JO sonp tos ” ” G) -"-Uuljo|[Ng JO Sa[Vs UIOIJ POAIODAL YSBVO 4, “TZ “09d 39 G8Fk ~~~988T ‘GT “oq ‘puvy Uo Ysvo oouLleq OF, ; “188 "a0 ‘uopburysn yy fo hyaroog yoorydosopyg ay) yp yUnOIP UL JadnsDasy, 94, "aq ¥ { \ . + | ; ey ren BULLETIN OF THE PHILOSOPHICAL SOCIETY OF WASHINGTON. ANNUAL ADDRESS OF THE PRESIDENT. XXXVii ‘ ‘ r co 4 WVER ANNUAL ADDRESS OF THE PRESIDENT, WILLIAM HARKNESS. Delivered December 10, 1887. THE PROGRESS OF SCIENCE AS EXEMPLIFIED IN THE ART OF WEIGHING AND MEASURING. Two centuries ago the world was just beginning to awaken from an intellectual lethargy which had lasted a thousand years. During all that time the children had lived as their parents before them, the mechanical arts had been at a standstill, and the dicta of Aristotle had been the highest authority in science. But now the night of medievalism was approaching its end, and the dawn of modern progress was at hand. Galileo had laid the foundation for accurate clocks by discovering the isochronism of the simple pendulum; had proved that under the action of gravity light bodies fall as rapidly as heavy ones; had invented the telescope and with it dis- covered the spots on the sun, the mountains on the moon, the sat- ellites of Jupiter, and the so-called triple character of Saturn; and after rendering himself immortal by his advocacy of the Copernican system, had gone to his grave, aged, blind, and full of sorrows. His contemporary, Kepler, had discovered the laws which, while history endures, will associate his name with the theory of planetary motion, and he also had passed away. The first Cassini was still a young man, his son was a little child, and his grandson and great-grand- son, all of whom were destined to be directors of the Paris Observa- | tory, were yet unborn. The illustrious Huyghens, the discoverer of Saturn’s rings and the father of the undulatory theory of light, was in the zenith of his powers. The ingenious Hooke was a little younger, and Newton, towering above them all, had recently in- vented fluxions, and on the 28th of April, 1686, had presented his Principia to the Royal Society of London and given the theory of gravitation to the world. Bradley, who discovered nutation and 44 Xxxix XL PHILOSOPHICAL SOCIETY OF WASHINGTON. the aberration of light; Franklin, the statesman and philosopher, who first drew the lightning from the clouds ; Dollond, the inventor of the achromatic telescope; Euler, the mathematician who was destined to accomplish so much in perfecting algebra, the calculus, and the lunar theory; Laplace, the author of the Mécanique Céleste; Rumford, who laid the foundation of the mechanical theory of heat; Dalton, the author of the atomic theory upon which all chemistry rests; and Bessel, the greatest of modern astrono- mers—these and others almost as illustrious, whom we cannot even name to-night, were still in the womb of time. Pure science first felt the effects of the new intellectual life and it was more than a century later before the arts yielded to its influ- ence. Then came Hargreaves, the inventor of the spinning-jenny; Arkwright, the inventor of the cotton-spinning frame; Watt, who gave us the condensing steam engine; Jacquard, the inventor of the loom for weaving figured stuffs ; Murdock, the originator of gas lighting; Evans, the inventor of the high-pressure steam engine; Fulton, the father of steam navigation; Trevithick, who ranks very near Watt and Evans in perfecting the steam engine; and Stephenson, the father of railroads. If now we add the names of those who have given us the telegraph, to wit: Gauss, the emi- nent physicist and the greatest mathematician of the present cen- tury ; Weber, Wheatstone, and Henry—all famous physicists—and — Morse, the inventor and engineer; we have before us the demi-gods who have transformed the ancient into the modern world, given us machinery which has multiplied the productive power of the human race many fold, annihilated time and space, and bestowed upon toiling millions a degree of comfort and luxury which was unknown to kings and emperors of old. The discoveries and inventions of the last two centuries have so far exceeded all others within historic times that we are amply jus- tified in calling this an age of phenomenal progress, and under the circumstances a little self-glorification is pardonable—perhaps even natural. The weekly and monthly records of scientific events which appear in so many newspapers and magazines are the imme- diate result of this, and the great increase of ephemeral scientific literature has led multitudes of educated people to believe that such records represent actual progress. The multiplication of bricks facilitates the building of houses, but does not necessarily ANNUAL ADDRESS OF THE PRESIDENT. XLI improve architecture. Similarly, the multiplication of minor inves- tigations improves our knowledge of details, but rarely affects the great philosophic theories upon which science is founded. The im- portance of human actions is measured by the degree in which they affect human thought, and the only way of permanently affecting scientific thought is by modifying or extending scientific theories. The men who do that are neither numerous, nor do they require weekly paragraphs to record their deeds; but their names are hon- ored by posterity. Even in this golden age the advance of science is not steady, but is made by spasmodic leaps and bounds. Mere scientific brick making, commonly called progress, is always the order of the day until some genius startles the world by a discovery affecting accepted theories. Then every effort is directed in the new line of thought until it is measurably worked out, and after that brick making again resumes its place. While the progress in two centuries has been immense, the progress in a week or a month is usually almost nil. Optimism has its uses in many departments of human affairs, but science should be cool and dispassionate, having regard only for the truth. To make a trustworthy estimate of the actual state of the whole vast realm of science would be a task beyond the powers of any one man; but perhaps it will not be amiss to spend the time at our disposal this evening in briefly reviewing the recent progress and present condition of the funda- mental processes upon which the exact sciences rest—I allude to the methods of weighing and measuring. Physical science deals with many quantities, but they are all so related to each other that almost every one of them can be ex- pressed in terms of three fundamental units. As several systems of such units are possible, it is important to select the most con- venient, and the considerations which guide us in that respect are the following: 1. The quantities selected should admit of very accurate com- parison with other quantities of the same kind. 2. Such comparisons should be possible at all times, and in all places. 3. The processes necessary for making such comparisons should be easy and direct. XLII PHILOSOPHICAL SOCIETY OF WASHINGTON. 4, The fundamental units should be such as to admit of easy defi- nitions and simple dimensions for the various derived units. Scientific men have long agreed that these requirements are best fulfilled by adopting as the fundamental units, a definite length, a definite mass, and a definite interval of time. Length is an element which can be very accurately measured and copied, but it must be defined by reference to some concrete material standard, as for example, a bar of metal, and as all substances expand and contract with changes of temperature, it is necessary to state the temperature at which the standard is correct. A standard of mass, consisting of a piece of platinum, quartz, or other material not easily affected by atmospheric influences, probably fulfills the conditions set forth above better than any other kind of magnitude. Its comparison with other bodies of approximately equal mass is effected by weigh- ing, and as that is among the most exact of all laboratory operations, very accurate copies of the standard can be made, and they can be carried from place to place with little risk of injury. Time is also an element which can be measured with extreme precision. The immediate instruments of measurement are clocks and chronometers, ‘but their running is checked by astronomical observations and the ultimate standard is the rotation of the earth itself. It is important to note that the use of three fundamental units is simply a matter of convenience and not a theoretical necessity, for the unit of mass might be defined as that which at unit distance would generate in a material point unit velocity in unit time; and thus we should have a perfectly general system of measurement based upon only two fundamental units—namely, those of space and time. Such a system is quite practicable in astronomy, but cannot yet be applied with accuracy to ordinary terrestrial purposes. Ac- cording to the law of gravitation Mass = Acceleration X (Distance)? and as in the case of the earth we can measure the quantities on the right-hand side of that equation with considerable accuracy, we can satisfactorily determine the earth’s mass in terms of the supposed unit. That suffices for the needs of astronomy, but for other scien- tific and commercial purposes a standard of mass having a magni- tude of about a pound is necessary, and as two such,masses can be compared with each other from five to ten thousand times more ANNUAL ADDRESS OF THE PRESIDENT. XLIII accurately than either of them can be determined in terms of the supposed unit, three fundamental units are preferable to two. The Chaldeans, Babylonians, Persians, Greeks, and Romans all seem to have had systems of weights and measures based upon toler- ably definite standards, but after the decline of the Roman Empire these standards seem to have been forgotten, and in the beginning of the sixteenth century the human body had so far become the standard of measurement that the units in common use, as for ex- ample, the foot, palm, etc., were frequently taken directly from it. The complete table of measures of length was then as follows: the breadth (not the length) of four barley corns make a digit, or finger breadth; four digits make a palm, (measured across the middle joints of the fingers;) four palms are one foot; a foot and a half is a cubit; ten palms, or two feet and a half, are a step; two steps, or five feet, are a pace; ten feet are a perch; one hundred and twenty-five paces are an Italic stadium ; eight stadia, or one thousand paces, are an Italic mile; four Italic miles, area German mile; and five Italic miles are a Swiss mile. It was then the practice to fur- nish standards of length in books by printing in them lines a foot or a palm long, according to the size of the page, and from these and other data it appears that the foot then used on the continent of Europe had a length of about ten English inches. In England the first attempts at scientific accuracy in matters of measurement date from the beginning of the seventeenth century, when John Greaves, who must be considered as the earliest of the scientific metrologists, directed attention to the difference between the Roman and English foot by tolerably accurate determinations of the former, and also attempted the investigation of the Roman weights. He was followed by Dr. Edward Bernard, who wrote a treatise on ancient weights and measures about 1685, and towards the end of the century the measurements of the length of a degree by Picard and J. D. Cassini awakened the attention of the French to the importance of rigorously exact standards. In considering the progress of science with respect to standards of length we may safely confine our inquiries to the English yard and the French toise and meter, for during the last two hundred years they have been almost the only standards adopted in scientific operations. The English measures of length have come down from the Saxons, but the oldest standards now existing are the Exchequer yards of XLIV PHILOSOPHICAL SOCIETY OF WASHINGTON. Henry VII(1490)' and Elizabeth (1588).? These are both brass end measures, the former being an octagonal rod about half an inch in diameter, very coarsely made, and as rudely divided into inches on the right hand end and intg sixteenths of a yard on the left hand end; the latter a square rod with sides about half an inch wide, also divided into sixteenths of a yard and provided with a brass bed having end pieces between which the yard fits. One end of the bed is divided into inches and half inches. Francis Baily, who saw this Elizabethan standard in 1856, speaks of it as ‘this curious instru- ment, of which it is impossible, at the present day, to speak too much in derision or contempt. A common kitchen poker, filed at the ends in the rudest manner by the most bungling workman, would make as goodastandard. It has been broken asunder; and the two pieces have been dove-tailed together: but so badly that the joint is nearly as loose as that of a pair of tongs. The date of this fracture I could not ascertain, it having occurred beyond the memory or knowledge of any of the officers at the Exchequer. And yet, till within the last 10 years, to the disgrace of this country, copies of this measure have been circulated all over Europe and America, with a parch- ment document accompanying them (charged with a stamp that costs £3. 10s. exclusive of official fees) certifying that they are true copies of the English standard.”* in the year 1742 certain members of the Royal Society of Lon- don, and of the Royal Academy of Sciences of Paris, proposed that, in order to facilitate a comparison of the scientific operations car- ried on in the two countries, accurate standards of the measures and weights of both should be prepared and preserved in the ar- chives of each of these societies. This proposition having been approved, Mr. George Graham at the instance of the Royal Society had two substantial brass rods made, upon which he laid off, with the greatest care, the length of three English feet from the stap- dard yard kept at the Tower of London. These two rods, together with a set of troy weights, were then sent over to the Paris Acad- emy, which body, in like manner, had the measure of a French half toise set off upon the rods, and keeping one, as previously agreed, returned the other, together with a standard weight of two mares, to the Royal Society. In 1835, Baily declared this copy of the half 143, p. 34, and 44, pp. 51-2. (See Bibliography on page xxix.) 243, p. 25. 334, p. 146. ANNUAL ADDRESS OF THE PRESIDENT. XLV toise to be of little value because the original toise-¢talon was of iron, and the standard temperature in France differed from that in England.’ In his opinion the French should have sent over an iron half toise in exchange for the English brass yard; but this criticism loses much of its force when it is remembered that in 1742 neither England nor France had fixed upon a temperature at which their standards were to be regarded as of the true length. On the return of the rod from Paris Mr. Graham caused Jonathan Sisson to divide the English yard and the French half toise each into three equal parts, after which the rod was deposited in the archives of the Royal Society, where it still remains.” Objection having been made that the original and legal standard yard of England was not the one at the Tower, but the Elizabethian standard at the Ex- chequer, the Royal Society requested Mr. Graham to compare his newly-made scale with the latter standard, and on Friday, April 22, 1748, he did so in the presence of a committee of seven mem- bers of the Royal Society. In the following week the same gentle- men compared the Royal Society’s scale with the standards at Guildhall and the Tower, and also with the standard of the Clock- makers’ Company. These comparisons having shown that the copy of the Tower yard upon the Royal Society’s scale was about 0°0075 of an inch longer than the standard at the Exchequer, Mr. Graham inscribed upon the Royal Society’s scale a copy of the latter stand- ard also, marking it with the letters Exch., to distinguish it from the former, which was marked E. (English), and from the half toise which was marked F. (French).’ In the year 1758 the House of Commons appointed a committee to inquire into the original standards of weights and measures of England; and, under instructions from that committee, the cele- brated instrument maker, John Bird, prepared two brass rods, respecting which the committee speak as follows in their report: “And having those rods, together with that of the Royal Society laid in the same place, at the receipt of the Exchequer, all night with the standards of length kept there, to prevent the variation which the difference of air might make upon them, they the next morning compared them all, and, by the means of beam compasses brought by Mr. Bird, found them to agree as near as it was possible.” * One of these rods was arranged as a matrix for testing end meas- 134, p.87. 76, pp. 185-8. 97, pp. 541-556. #11, p. 434. XLVI PHILOSOPHICAL SOCIETY OF WASHINGTON. ures, and the other was a line measure which the committee recom- mended should be made the legal standard of Erfgland, and which has since been known as Bird’s standard of 1758. Respecting the statement that after lying together all night the rods were a// found to agree as near as it was possible, Baily says: “This is somewhat remarkable, and requires further explanation, which unfortunately cannot now be accurately obtained. For it is notorious that the meas- ure of the yard of the Royal Society’s scale differs very considerably from the standard yard at the Exchequer: * * * Owing to this singular confusion of the lengths of the measures, which does not appear to have been unraveled by any subsequent Committee, it has happened that the Imperial standard yard * * * has been assumed nearly 1 + 140 of an inch longer than the ancient measure of the kingdom.”* There is little difficulty in surmising what Bird did. The Exchequer standard consisted of a rod and its matrix. The Royal Society’s committee assumed the rod to be the true standard of 36 inches, and upon that assumption Graham’s measurements gave for the length of the matrix 36°0102 inches, and for the length of the Royal Society’s yard 36:0075 inches. The Parliamentary committee of 1758 probably assumed the standard to consist of the rod and matrix together, which seems the better view; and by laying the rod in its matrix and measuring to the joint between them, Bird would have got a length of about 36-0051 inches. The mean between that and 36°0075 would be 36:0063, which differs very little from the length of Bird’s standard result- ing from Sir George Shuckburgh’s measurements. Thus the com- mittee’s statement is justified, and there has been no falsification of the ancient standards. On December 1, 1758, Parliament created another committee on weights and measures which in April, 1759, repeated the reeommen- dation that Bird’s standard of 1758 should be legalized, and further recommended that a copy of it should be made and deposited in some public office, to be used only on special occasions.” The copy was made by Bird in 1760, but owing to circumstances entirely un- connected with the subject, no legislation followed for sixty-four years. The Royal Commission appointed during the reign of George III, to consider the subject of weights and measures, madevits first report 134, p. 43. 212, p. 463. ANNUAL ADDRESS OF THE PRESIDENT. XLVII on June 24, 1819, and therein recommended the adoption of the standard of length which had been used by General Roy in measur- ing the base on Hounslow Heath ;* but in a second report made July 13, 1820, they wrote,“We * * * have examined, since our last report, the relation of the best authenticated standards of length at present in existence, to the instruments employed for measuring the base on Hounslow Heath, and in the late trigonome- trical operations—But we have very unexpectedly discovered, that an error has been committed in the construction of some of these instruments:? We aretherefore obliged to recur to the originals which they were intended to represent, and we have found reason to prefer the Parliamentary standard executed by Bird in 1760, which we had not before received, both as being laid down in the most ac- curate manner, and as the best agreeing with the most extensive comparisons, which have been hitherto executed by various observers, and circulated through Europe; and in particular with the scale employed by the late Sir George Shuckburgh.”* Accordingly, when in 1824 Parliament at length took action, Bird’s standard of 1760 was adopted instead of that of 1758. The former being a copy of a copy, its selection as a national standard of length seems so singular that the circumstances which brought about that result should scarcely be passed over in silence. Bird had a very accurate brass scale 90 inches long, which he used in all his dividing operations, whether upon circles or straight lines, and which Dr. Maskelyne said was 0°001 of an inch shorter on three feet than Graham’s Royal Society yard E.* In the year 1792, or 1793, the celebrated Edward Troughton made for himself a five _ foot scale, which conformed to Bird’s, and which he afterwards used in laying down the divisions of the various instruments that passed through his hands. This was the original of all the standard scales he ever made, and at the beginning of the present century he be- lieved these copies, which were made by the aid of micrometer microscopes, to be so exact that no variations could possibly be de- tected in them, either from the original or from each other. Among the earliest of the scales so made by Troughton was the one used by Sir George Shuckburgh in 1796-8 in his important scientific opera- tions for the improvement of the standards. Subsequently, the length of the meter was determined by comparison with this scale 123, p. 4. 327, p. 92. $24, p. 3; also, 25 and 26. #13, p. 326. XLVIII PHILOSOPHICAL SOCIETY OF WASHINGTON. and with the supposed fac-simile of it made by Troughton for Pro- fessor Pictet, of Geneva, and thus it happened “that on the conti- nent of Europe all measures were converted into English units by a reference to Sir George Shuckburgh’s scale. The Royal Commis- sion of 1819, believed Bird’s standard of 1760 to be identical with Shuckburgh’s scale, and they legalized it rather than the standard of 1758, in order to avoid disturbing the value of the English yard which was then generally accepted for scientific purposes. There are yet four other scales of importance in the history of English standards—namely, the brass five-foot scale made for Sir George Shuckburgh by Troughton in 1796; two iron standard yards, marked 1A and 2A, made for the English Ordnance Survey department by Messrs. Troughton and Simms in 1826-’7, and the Royal Society’s standard yard constructed by Mr. George Dollond, under the direction of Captain Henry Kater, in 1851. Bearing in mind the preceding history, the genesis of the present English standard yard may be thus summarized: In 1742 Graham transferred to a bar made for the Royal Society a length which he intended should be that of the Tower yard, but which was really inter- mediate between the Exchequer standard yard of Elizabeth and its matrix. That length he marked with the letter E, and, although destitute of legal authority, it was immediately accepted as the scientific standard and was copied by the famous instrument makers of the time with all the accuracy then attainable. Thus itis in fact the prototype to which all the accurate scales made in Eng- land between 1742 and 1850 can be traced. Bird’s standard of 1758 was compared with the Exchequer standard and with the Royal Society’s yard E, and was of a length between the two. Bird’s standard of 1760, legalized as the Imperial standard in June, 1824, was copied from his standard of 1758. After becoming the Im- perial standard, Bird’s standard of 1760 was compared with Sir George Shuckburgh’s scale by Captain Kater in 1830 and by Mr. Francis Baily in 1834; with the Ordnance yards 1A and 2A in 1834 by Lieutenant Murphy, R. E., Lieutenant Johnson, R. N., and Messrs. F. Baily and Donkin; and with Kater’s Royal Society yard by Captain Kater in 1831. On October 16th, 1834, the Im- perial standard (Bird’s standard of 1760) was destroyed by the burning of the Houses of Parliament, in which it was lodged, and very soon thereafter the Lords of the Treasury took measures to ANNUAL ADDRESS OF THE PRESIDENT. XLIX recover its length. Preliminary inquiries were begun on May 11, 1838, and on June 20, 1843, they resulted in the appointment of a Commission to superintend the construction of new Parliamentary standards of length and weight, among whose members the Astron- omer Royal (now Sir George B. Airy), Messrs. F. Baily, R. Sheep- shanks, and Prof. W. H. Miller, were prominent. The laborious investigations and experiments carried out by that Commission can- not be described here, but it will suffice to say that for determining the true length of the new standard Mr. Sheepshanks employed a provisional yard, marked upon a new brass bar designated “ Brass 2,” which he compared as accurately as possible with Sir George Shuckburgh’s scale, the two Ordnance yards, and Kater’s Royal Society yard. The results in terms of the lost Imperial standard were as follows: Brass bar 2 = 36:000084 from comparison with Shuckburgh’s scale, 0-36 in. 36-000280 ” - bs «10-46 in. 36000303 from comparison with the Ordnance yard, 1A. 36:000275 “cc ce ce ce cc DA? 36-000229 from Capt. Kater’s Royal Society yard. Mean — 86:000284 Respecting this mean Mr. Sheepshanks wrote: “This should be pretty near the truth; but I prefer 36:00025, if in such a matter such a difference be worth notice. I propose, therefore, in con- structing the new standard to assume that— Brass bar 2 = 36:00025 inches of lost Imperial standard at 62° Fah.”’ And upon that basis the standard now in use was constructed.’ Turning now to the French standards of length, it is known that the ancient toise de macons of Paris was probably the toise of Charlemagne (A. D. 742 to 814), or at least of some Emperor Charles, and that its étalon was situated in the court yard of the old Chatelet, on the outside of one of the pillars of the building. It still existed in 1714, but entirely falsified by the bending of the upper part of the pillar. In 1668 the ancient toise of the masons was reformed by shortening it five lines; but whether this reforma- tion was an arbitrary change, or merely a change to remedy the 141, p. 664. L PHILOSOPHICAL SOCIETY OF WASHINGTON. effects of long use and restore the étalon to conformity with some more carefully preserved standard, is not quite clear." These old étalons were iron bars having their two ends turned up at right angles so as to form talons, and the standardizing of end measures was effected by fitting them between the talons. Being placed on the outside of some public building, they were exposed to wear from constant use, to rust, and even to intentional injury by malicious persons. Under such conditions every étalon would, sooner or later, become too long and require shortening. Respecting the ancient toise of the masons there are two contra- dictory stories. On December 1, 1714, La Hire showed to the French Academy what he characterized as “a very ancient instru- ment of mathematics, which has been made by one of our most ac- complished workmen with very great care, where the foot is marked, and which has served to re-establish the toise of the Chatelet, as I have been informed by our old mathematicians.”” Forty-four years later, on July 29, 1758, La Condamine stated to the Academy that “We know only by tradition that to adjust the length of the new standard, the width of the arcade or interior gate of the grand pa- vilion, which served as an entrance to the old Louvre, on the side of the rue Fromenteau was used. This opening, according to the plan, should have been twelve feet wide. Half of it was taken to fix the length of the new toise, which thus became five lines shorter than the old one.”* Of these two contradictory statements that of La Hire seems altogether most trustworthy, and the ordinary rules of evidence indicate that it should be accepted to the exclusion of the other. In 1668 the étalon of the new toise, since known as the toise-étalon du Chatelet, was fixed against the wall at the foot of the staircase of the grand Chatelet de Paris—by whom or at what season of the year is not known. Strange as it now seems, this standard—very roughly made, exposed in a public place for use or abuse by every- body, liable to rust, and certain to be falsified by constant wear— was actually used for adjusting the toise of Picard, that of Cassini,. the toise of Peru and of the North, that of La Caille, that of Mairan —in short, all the toises employed by the French in their geodetic operations during the seventeenth and eighteenth centuries. The lack of any other recognized standard made the use ofthis one im- 11, p. 536 and 2, p. 395. 22, p. 395. $14, p. 484. ANNUAL ADDRESS OF THE PRESIDENT. LI perative, but the French academicians were well aware of its defects and took precautions to guard against them. The first toise copied from the étalon of the Chatelet for scientific purposes was that used by Picard in his measurement of a degree of the meridian between Paris and Amiens.’ It was made about the year 1668, and would doubtless have become the scientific standard of France had it not unfortunately disappeared before the degree measurements of the eighteenth century were begun. The second toise copied from the étalon of the Chatelet for scientific purposes was that used by Messrs. Godin, Bouguer, and La Condamine for meas- uring the base of their arc of the meridian in Peru. This toise, since known as the toise du Pérou, was made by the artist Langlois under the immediate direction of Godin in 1735, and is still pre- served at the Paris Observatory.’ It is a rectangular bar of polished wrought iron, having a breadth of 1°58 English inches and a thick- ness of 0°30 of an inch. All the other toises used by the Academy in the eighteenth century were compared with it, and, ultimately, it was made the legal standard of France by an order of Louis XV, dated May 16,1766. As the toise of Peru is the oldest authentic copy of the toise of the Chatelet, the effect of this order was simply — to perpetuate the earliest known state of that ancient standard. The metric system originated from a motion made by Talleyrand in the National Assembly of France, in 1790, referring the question of the formation of an improved system of weights and measures, based upon a natural constant, to the French Academy of Sciences ; and the preliminary work was entrusted to five of the most eminent members of that Academy—namely, Lagrange, Laplace, Borda, Monge, and Condorcet. On March 19, 1791, these gentlemen, to- gether with Lalande, presented to the Academy a report contain- ing the complete scheme of the metric system. In pursuance of the recommendations in that report, the law of March 26, 1791, was enacted for the construction of the new system, and the Academy of Sciences was charged with the direction of the necessary opera- tions. Those requisite for the construction of a standard of length were: 1. The determination of the difference of latitude between Dun- kirk and Barcelona. 15, Art. 4, p. 15. 214, p. 487 and 46, p. C.2. LII PHILOSOPHICAL SOCIETY OF WASHINGTON. 2. The remeasurement of the ancient bases which had served for the measurement of a degree at the latitude of Paris, and for mak- ing the map of France. 3. The verification by new observations of the series of triangles employed for measuring the meridian, and the prolongation of them as far as Barcelona. This work was entrusted to Méchain and Delambre, who carried it on during the seven years from 1791 to 1798, notwithstanding many great difficulties and dangers. The unit of length adopted in their operations was the toise of Peru, and from the are of 9° 40’ 45” actually measured, they inferred the length of an arc of the meri- dian extending from the equator to the pole to be 5,130,740 toises. As the meter was to be one ten millionth of that distance, its length was made 0°5130740 of a toise, or, in the language of the committee, 443-296 lines of the toise of Peru at a temperature of 15° Reaumur (162? Mok G12 Ee Before attempting to estimate how accurately the standards we have been considering were intercompared it will be well to describe briefly the methods by which the comparisons were effected. In 1742 Graham used the only instruments then known for the pur- pose—namely, very exact beam compasses of various kinds, one having parallel jaws for taking the lengths of the standard rods, another with rounded ends for taking the lengths of the hollow beds, and still another having fine points in the usual manner. The jaws, or points, of all these instruments were movable by micro- meter screws having heads divided to show the eight hundredth part of an inch directly, and the tenth of that quantity by estima- tion; but Mr. Graham did not consider that the measurements could be depended upon to a greater accuracy than one 1600th of an inch.’ Troughton is generally regarded as the author of the application of micrometer microscopes to the comparison of standards of length, but the earliest record of their use for that purpose is by Sir George Shuckburgh in his work for the improvement of the standards of weight and measure in 1796-8. Since then their use has been general; first, because they are more accurate than beam compasses, 119, pp. 432, 438 and 642. 27, pp. 645-6. 918, p. 187. ANNUAL ADDRESS OF THE PRESIDENT. LIIlI and, second, because they avoid the injury to standard scales which necessarily results from placing the points of beam compasses upon their graduations. As the objective of the microscope forms a mag- nified image of the standard, upon which the micrometer wires are set by the aid of the eye piece, it is evident that in order to reduce the effect of imperfections in the micrometer, the objective should have the largest practicable magnifying power. To show the pro- gress in that direction the optical constants of the microscopes, by means of which some of the most important standards have been compared, are given in the accompanying table. Wan ui be oe 3) oe . A o CWP Cle Cana E Dr Ties wns os Observer. = ES ire cas re alloy Cesk ooo wie | SS Sb sous 3 2 Bu | ce BES 3 3 ao aS) aoO8 a = = cs > Inches. | Inches. 1797 |; Sir Geo. Shuckburgh —.--__=__._ 14 Tat 1.50 | 0-01000 tein peapt. Henry iater 28 oy ke 18 (aro See ee “00428 SHSe ee CAM GIseis wily: =o sl ke la Le 27 (2.0) 3 00500 Bee ree MUL yy. Wy eee ee (Oy fe “00500 Boom) | We. mmcepsianks <5. es ae (2) | See ae 00358 TeGenGens Avr. Clarkes, Heo. otuse 60 4. 0.67 00287 1880 | Prof. W. A. Rogers, 1 in. obj. ---|__-__- LAs 8 ieee ae 00079 ee ebb ODI. pee (Se.6) Po seoee ls 00035 Ks a ae ON 2 PE eS (Bae ie ee 00019 7.5 0.83 | 0:00394 1888 | International Bureau ___________ 90 Norr.—The magnifying power of Sir Geo. Shuckburgh’s microscope seems to be referred to a distance of twelve inches for distinct vision. The powers inclosed in parentheses are estimated upon the assumption that the respective micrometer screws had one hundred threads per inch. In the memoirs of the French Academy nothing is said respect- ing the method adopted by the Academicians for comparing their various toises ; but in his astronomy, Lalande states that the com- parisons were effected partly by beam compasses, and partly by superposing the toises upon each other and examining their ends, both by touch and with magnifying glasses; they being all end standards.’ For the definitive adjustment of the length of their 116, p. 8. LIV PHILOSOPHICAL SOCIETY OF WASHINGTON. meters, which were also end standards, the French Metric Commis- sion used a lever comparator by Lenoir. In 1742 Graham used beam compasses, which he considered trust- worthy to 0°00062 of an inch, in comparing standards of length ; but at that time the French Academicians made their comparisons of toises only to one twentieth, or one thirtieth of a line, say 0:00300 of an inch, and it was not until 1758 that La Condamine declared they should be compared to 0°01 of a line, or 000089 of an English inch “if our senses aided by the most perfect instruments can attain to that.”? Half a century later, ten times that accuracy was attained by the lever comparator of Lenoir, which was regarded as trust- worthy to 0°000077 of an inch.” The heads of micrometer microscopes are usually divided into one hundred equal parts, and if we regard one of these parts as the least reading of a microscope, then in 1797, Sir George Shuckburgh’s microscopes read to one ten thousandth of an inch; and the least reading of microscopes made since that date has varied from one twenty thousandth to one thirty-five thousandth of an inch. . THE ECONOMIC PHASE OF THE ENGLISH SPARROW QUESTION. [This paper appeared in the Report of the Commissioner of Agriculture, 1886, 8°, Washington, Government Printing Office, 1887, pp. 227-246; with map. ] Respecting the law protecting sparrows Mr. Hazen drew atten- tion to the fact that a colored boy had recently been fined two dollars in the Police Court of Washington for throwing stones at sparrows. Mr. W J McGer made an oral communication entitled THE QUATERNARY DEPOSITS AND THE GREAT DISPLACEMENT OF THE MIDDLE ATLANTIC SLOPE, embodying the results of investigations set forth in part in a memoir on the geology of the head of Chesapeake Bay, contained in the Seventh Annual Report of the U.S. Geological Survey, and in part in an article entitled Three Formations of the Middle Atlantic Slope, which is expected to appear in the American Journal of - Science for February and March, 1888. 304TH MEETING. May 21, 1887. The President in the Chair. Forty-five members and guests present. Mr. C. Ek. Durron made a communication on P A RECENT VISIT TO THE SCENE OF THE CHARLESTON EARTH- QUAKE AND RESULTING CONCLUSIONS. Mr. W. H. Dau made a communication entitled SOUTH FLORIDA NOTES. Remarks on this communication were made by Messrs. Bov- TELLE, HEAD, and Toner. Adjourned to October 15. GENERAL MEETINGS. 17 305tH MEETING. OcToBER 15, 1887. The President in the Chair. Fifty-one members and guests present. The President announced the death at Wood’s Holl, Massachu- setts, on August 19, 1887, of Prof. Spencer FuLLertTon Barrp, one of the original members of the Society. Mr. C. E. Durron made a communication ON THE DEPTH OF EARTHQUAKE FOCI. [Abstract. ] Mr. Dutton first referred to the various methods which had been resorted to in order to ascertain the depths of earthquake foci. The method suggested by Mallet and based on the assumption that the lines of fracture in the walls of buildings tended to arrange them- selves transversely to the direction of propagation, he believed to be unavailable and not sustained by observation. The motions of buildings ‘and of the ground itself during an earthquake were highly complex, and, moreover, the lines of fracture, he believed, were influenced far more forcibly by the nature of the structure, the openings in the walls, and the natural directions of vibration than by the directions of the impulses themselves. Seebach’s method, by ascertaining the variation of the speed of the wave along the surface of the ground in the vicinity of the epi- centrum, was regarded as impracticable, though the mathematical considerations upon which it was founded were doubtless correct. The speed of propagation is so high and the difficulty of obtaining time observations of sufficient precision is so great that this mode of solution must fail for want of the requisite data. Seebach seems to have been under the impression that this speed was not more than a very few hundred metres per second. The Charleston earth- quake was transmitted with a speed probably exceeding 5,000 metres per second, and Mr. Dutton was of the opinion that all true earth- quakes were propagated with a speed differing but little from that ; but, even if the speed were no greater than Seebach supposed, it 48 18 PHILOSOPHICAL SOCIETY OF WASHINGTON. would still be expecting too much of human fallibility to suppose that data of sufficient accuracy could ever be obtained. There is, however, a method which is dependent, not upon time data, but upon observations of intensity, which seems to offer the means of computing the desired quantity. It is well known that the intensity or energy per unit area of wave front diminishes as the wave moves outwards from the centrum. Like all radiant energy, it must be subject to the law of variation inversely as the square of the distance. If the elasticity of the medium were perfect and its density uniform the law would be rigorous. As a matter of fact, it is not so; but, on the other hand, we are assured that the elasticity cannot be very imperfect, since if it were so the propaga- tion of impulses to very great distances would be impossible, and the waves would soon be extinguished in work done upon the me- dium itself. Nor is there reason to suppose that the variations of density are extreme. Thus, while the law of inverse squares may be in some measure impaired, it may still be assumed as an approxi- mate expression of the reality. If, then, we were able to form a just estimate of the rate of varia- tion of the intensity along lines radiating from the epicentrum, we should have the means of computing the depth of the focus. Thus, if O be the focus and E the epicentrum and P any point at a dis- tance from the epicentrum, the intensity at P would be inversely proportional to the square of OP. Calling EP = 2,0 P=r, and OE = q, and designating by a the intensity at unit distance and by y the intensity at any other distance x, we have the equation: ~ This equation corresponds to a curve whose figure is approxi- GENERAL MEETINGS. 19 mately represented in the diagram, and the curve will have a point of inflexion at which the decrease in the value of y as EP in- creases will be a maximum. Differentiating the equation twice and equating the value of the second differential coefficient to zero will give us the co-ordinates of this point of inflexion. The value of the abscissa of this point will be | ie V3 Ui yi —— From this value the constant a has disappeared, showing that it is independent of the intensity of the original shock and dependent upon the depth alone. The application of this analysis to the problem is as follows: As we recede from the épicentrum the inten- sity diminishes, but it does not diminish at a uniform rate with the distance. ‘There is some critical distance from the epicentrum at which the rate of decrease of intensity has a maximum yalue. This critical distance depends upon the depth of the focus and upon nothing else, and the magnitude of this distance is equal to the depth divided by 3, and, conversely, the depth of the focus is equal to the critical distance multiplied by 1/3. If, then, we can locate the epicentrum and the points where the intensity diminishes with greatest rapidity, we have at once the means of determining the depth of the focus. In the case of the Charleston earthquake this location has been approximately made and a depth of about twelve miles has been deduced for the focus of the principal shock. After a description of Mallet’s second method of investigation by the observation of the overturning power of earthquakes, the sub- ject was discussed by the President and by Messrs. H. Farquuar, GILBERT, and Dutton. Mr. F. W. CLarkeE made an oral communication on the MANCHESTER MEETING OF THE BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, 1887. Remarks upon this communication were made by Mr. ABBE. 20 PHILOSOPHICAL SOCIETY OF WASHINGTON. 306TH MEETING. OcToBER 29, 1887. > The President in the Chair. Forty-one members and guests present. Announcement was made by the President of the election to and acceptance of membership of Mr. Jrsss Herman Homes. The President also referred to the loss sustained by the scientific world in the death of Prof. Spencer F. Barrp, and announced that the General Committee had taken the preliminary steps for arranging a memorial meeting in commemoration of his life and scientific work. Mr. CLEvELAND ABBE read the following paper entitled THE SIGNAL SERVICE BIBLIOGRAPHY OF METEOROLOGY. Mr. ABBE stated that in 1872 he began, at his own expense and for personal use, a more systematic collection of the titles of works bearing upon all subjects that he was interested in, especially meteorology. After corresponding in 1874 with the committee of the Royal Society as to the probability of the publication of their proposed subject-index to their Catalogue of scientific papers, and being officially informed that this work would not be under- taken, he decided to complete his systematic examination of all the titles in that great work and copy the appropriate ones for his own use. In 1878, when this work was nearly completed, so far as regards the first six volumes, he addressed a note to Prof. Hann, of Vienna, stating what he had done and inquiring whether any one in Europe was similarly engaged. Almost simultaneously with this Prof. Hann received and published’ a letter from Dr. Hell- mann, of Berlin, dated January 10, 1879, urging the importance of a general index to the literature of meteorology. This letter had evidently been suggested by a circular issued in October, 1878, by the permanent committee of the first meteorological congress at Vienna, proposing a programme for the second congress about to be held at Rome in the approaching month of April, 1879. In this circular the committee asked that the delegates prepare catalogues 1Ztschr. Met., Wien, 1879, xiv, 96. GENERAL MEETINGS. 21 of the meteorological observations, published or unpublished, for their respective countries. At the Rome conference Dr. Hellmann’s letter was presented on April 21 and by the congress referred to the newly-appointed Inter- national meteorological committee. The congress also adopted resolutions’ asking the delegates to prepare lists of the observations for their respective countries, and the directors of meteorological libraries to add lists of the works not found in the published library catalogues of the Meteorological society of London and the observ- atory at Brussels, or in Mr. Abbe’s cards. After the meeting at Rome Mr. Abbe received a letter from Dr. Hellmann, to which he replied August 22, 1879, offering to co- operate in the preparation of a general bibliography and to transfer his cards either to the International meteorological committee or to Dr. Hellmann personally, on the repayment of his expenses. At the same time a similar offer was made to General Myer, Chief signal officer, under the impression that the latter would be pleased to complete the work as an official matter. At the first or Berne meeting of the International meteorological committee in August, 1880, letters of Dr. Hellmann were read dated January 20 and July 20, 1880, giving a detailed scheme for combining the various works and for the preparation of a catalogue, and embodying Mr. Abbe’s proposal of August, 1879, as well as a similar one from Mr. G. J. Symons of London’. The committee, however, resolved that each country be requested to furnish lists of observations and that Messrs. Scott and Hellmann be a sub- committee to consider the means of carrying out Dr. Hellmann’s scheme.* In the fall of 1881, Mr. Abbe wrote to Mr. Symons for more de- tails as to his work. Mr. Symons’ reply and Mr. Abbe’s renewal of his previous offer were then laid before General Hazen, Chief signal officer, who decided to purchase the catalogues of both these gentlemen with a view to their combination and completion by the Signal office in case the International committee did not do this. In November, 1881, Mr. Symons was authorized to prepare at the expense of the Signal office, a copy of all meteorological titles in his ?Rep. pr. internat. meteoral. cong. Rome 1879, Lond., 1879, p. 21, 75. 3 Rep. pr. internat, meteoral. comm. Berne 1880, eee , 1881, p. 38, 40. 4Thid., p. 8-9. 22 PHILOSOPHICAL SOCIETY OF WASHINGTON. collection, and in December, 1881, M- Abbe’s cards were pur- chased. Mr. Symons’ catalogue was received in October, 1883, and on March 4, 1884, Mr. C. J. Sawyer, librarian of the Signal office, was relieved from the care of the library, and, as bibliographer, ordered to devote his whole time to the completion of this work, which was then transferred from the library to the study room division of the Signal office. At the second meeting of the International meteorological com- mittee, at Copenhagen, in August, 1882, Messrs. Scott and Hell- | mann reported that the Meteorological office could not print the proposed catalogue and that subscriptions were not practicable. They therefore recommended each meteorological service to publish a national bibliography, for which Hellmann’s Repertorium der deutschen Meteorologie, prepared in accordance with the ideas of the committee and now just about to be published, should serve as a model. It need only be added that since 1882 the International meteorological committee have, with other meteorologists, acqui- esced in the arrangement by which the Signal service has under- taken to complete and, if possible, publish for its own and for gen- eral use a general index to the literature of meteorology. The importance of this work is especially endorsed by General Greely, who, in his current annual report, October, 1887, as Chief signal officer, says: The practical value of such a bibliography has been fully shown by its constant use in current office work, and, in addition to the official demands, almost daily calls for information have been re- ceived from parties not connected with the service. The result of this work is the collection of special bibliographies, which ensures those consulting it a complete index of what has been accomplished in each special line of meteorology. As has been well said, the progress of meteorology is retarded and labor therein wasted owing to the impossibility of ascertaining what has been done in its various branches—an experience which, as scientific men well know, is by no means confined to this science. The cost of time and labor to the Government for the preparation of this work cannot be less than $12,000 to $15,000, and the result of these labors has been the com- pletion of a work which is of great value, both practically and sci- entifically, to the entire world. The catalogue in its present condi- tion is valuable, and sufficient for the pressing needs of this service, but to view it in this light would evince a narrow and selfish dispo- sition not in keeping with the scientific spirit of the age. At a cost GENERAL MEETINGS. 93 of probably $8,000 or $19,000 this work can be printed and dis- tributed to the world as a monument and evidence of the growing scientific tendency of this nation. If such action is taken by Con- gress, the Chief Signal Officer has no doubt, from the willing spirit and hearty co-operation shown by leading scientists of other coun- tries, that future international co-operation will secure, by a system of rotation, from the various European governments the publication of a series of supplements which will keep the world abreast of the steadily increasing volume of meteorological publications. A large number of American and foreign meteorologists and librarians have given largely of their time and energy in the compilation of this bibliography, as is shown by the fact that over one-half of the mate- rial has been contributed from foreign countries, so that the bibli- ography represents not only a large expenditure on the part of the United States, but also many years of additional gratuitous labor. The material could not be duplicated, and it would seem but a re- spectable reciprocity of exchange that the Government should print the catalogue, so as to enable the voluntary contributors to avail themselves of the complete work. This fulfilment of obligations to contributors by a public catalogue is an act of justice; but, in addi- tion, it should be considered that this bibliography will be of great practical value to the agricultural, commercial, engineering, and medical interests not only of the United States, but of the world. Mr. ABBE stated that he had asked Mr. Sawyer to present to the Philosophical society some account of his work, now nearing com- pletion, but, as he could not be present, Mr. Abbe read the following memorandum prepared by Mr. Sawyer: MEMORANDUM ON THE SIGNAL SERVICE BIBLIOGRAPHY OF METEOROLOGY AND TERRESTRIAL MAGNETISM. The bibliographical work of the Signal office dates from 1881, and officially originated in correspondence begun by Prof. Abbe with Prof. G. J. Symons, of London, Dr. G. Hellmann, of Berlin, and Dr. A. Lancaster, of Brussels, who all manifested the greatest interest in the proposed catalogue and have been the most impor- tant contributors to it. The meteorological titles in the Catalogue of scientific papers. Compiled by the Royal society of London, vols. i-vi (z800-1863), had already been selected and extracted by Prof. Abbe and were trans- ferred to the Signal office in December, 1881, on the repayment of the expenses incurred by him in the work. At the request of the Signal office. Prof. Symons undertook to furnish copies of all titles on meteorology and terrestrial magnetism contained in his extensive 24 PHILOSOPHICAL SOCIETY OF WASHINGTON. collection of titles on astronomy, meteorology, and allied sciences, the expense to the office to be only his actual outlay for clerical assistance. Prof. Symons’ catalogue already represented many years of bibliographical research, and to it he now added many titles, securing the co-operation of European meteorologists by per- sonal visits and by correspondence, and including the more impor- tant English libraries. This catalogue was received late in 1883, about two years having been spent in its compilation; it consisted of about 18,000 titles, chiefly of separate works, and may be considered as the foundation of the present bibliography. No further work was done until March, 1884, when an effort to secure the services of Prof. Lancaster having failed, the librarian of the Signal office was assigned to the work of preparing the catalogue for publication. The original intention had been to extend Prof. Symons’ work only by the combination of titles from the Royal Society catalogue, including those in vols. vii and viii (1864-1873), selected but not yet copied by Prof. Abbe, the catalogue to be arranged by authors and to form only a first contribution to the general meteoro- logical bibliography desired. But the large amount of material on hand, and the conviction that some recent contributions to the subject, especially the Reper- torium der deutschen Meteorologie by Dr. Hellmann, should be in- cluded, and that the periodical literature previous to 1800 and subsequent to 1873 should be represented, led to the consideration of an enlargement in the scope of the work. It was foreseen that the necessary delay in securing an appropriation for publication would afford opportunity for still further extension, and it was decided March 15, 1884, to complete the compilation so far as possible without postponing publication for this purpose and to issue an approximately complete general bibliography, of such form as to serve as a basis for supplementary volumes. In pursuance of this plan, every effort has been made to secure contributions, especially by indexing periodicals, by examination of printed and manuscript catalogues and bibliographies, and by cor- respondence with meteorologists and librarians. The lacunz in periodical literature have been filled by indexing all periodicals available previous to 1800 and subsequent to 1873, and by the examination of all indexes, bibliographies, &ec., avail- able, such as Reuss, Young, Poggendorff, Kerl, Fortschritte der GENERAL MEETINGS. 25 Physik, and many others. It was found that the general indexing of the Royal society for the period from 1800 to 1878, was not full enough for this special bibliography, and all periodicals rich in meteorological literature were reindexed. The International meteorological committee had already consid- ered the subject of meteorological bibliography, and, unable to secure at once the publication of a general bibliography, had recommended that each country compile a list of its own observations and that special national bibliographies be prepared wherever possible. Some work had been done in accordance with this recommendation, especially in Germany and Russia, and an attempt was made by the Signal office to secure the extension of this work and to obtain from foreign meteorologists and librarians, bibliographies for their respective countries. The great interest in the work was shown by the hearty co-operation from all sections. Among the special bibliographies received the following may be mentioned as among the most complete and valuable: Germany, by Dr. Hellmann; Japan, by Dr. Knipping; Norway, by Prof. Mohn ; Poland, by Prof. Karlinski; Portugal, by J. C. de Brito—Capello ; Roumania, by Dr. Hepites; Russia, by Profs. Wild and Woeikof ; South Africa, by Dr. Gamble; Sweden, by C. G. Fineman and C. Annerstedt ; Victoria, by R. L. J. Ellery. All the meteorological libraries of the world are represented, in- cluding, as worthy of special mention, those of the Meteorological office and Royal Meteorological Society, of London; the Societé météorologique de France, Paris; the large manuscript collection of Prof. Poey, the Ronald’s, Poulkova, and Brussels catalogues, all contained in the catalogue of Prof. Symons; the Deutsche Seewarte, Hamburg (including the library of the late Prof. Dove), and the k. k. Central-Anstalt, of Vienna (with that of Prof. Hann), added by the Signal office. The number of scientific and general libraries represented is very large. Letters, requesting lists of their works, were sent to about 400 writers (exclusive of those in Germany, where this method had been employed by Dr. Hellmann), and the replies received have been of the greatest value in the representation of living authors. The desirability of securing as great completeness as possible, the expectation of an early publication, and the fact that the Symons and Hellmann catalogues ceased with 1881, led to the adoption of this date as the close of the bibliography, and the following state- 26 PHILOSOPHICAL SOCIETY OF WASHINGTON. ment of the titles on hand includes only those of works published before January 1,1882. ee Bee 22S ® o2°0o > a & Bsc Zi A < a us ys eames) it rf ae Se yd se 1872 eco)h) 24 sesh cere ee LST oe 2a 2S ieee ee eee ee 1874 sou hla nesses 1875-2]: 22) 24, Meets 35 .29 Meh (KO) soe Biel ae a oe a Se 37 es 1S 2e =) LO Sif 255 aa 40 ay 1878 ___- Bi a cs Mit Bde pera 40 oh 1879 ...-|, 22 | 185, Apr, 2 -- 40 29 Anth. Soc., Feb. 17. 1880... 19 | 154, July 20__ 41 | Biol. Soc., Dec. 3. 1881...) 18. | 162, dimly 182: 38 25 1882 2...) 16 | 149, May i... 34 .23 1883 42.4), 17 9-149, Dee 31-2 38 26 Math. Sec., Mar. 29. 1884 _.-..| 385 | 178, Dee. 20_+ 42 .26 Chem. Soc., Jan. 31. 1885_---| 22 | 179, Jan.16__| 47 OR PESGet2— |, 718 183, Dec. 18_- 47 AAG VSSieSe a lo aLOle Mec iale ae 49 .26 Meaniues!” 18.6 | seen ayo 40 .265 In a general way there has been a continuous growth of the So- ciety as regards membership, and the rate of growth, whether con- sidered as a geometric ratio or as an arithmetic increment, has progressively diminished. The average attendance has likewise increased, but its law is not evident. The ratio of attendance to membership has ranged in ten recorded years from .23 to .29, the mean being .265. The total active membership passed through a secondary maximum in 1880 and a minimum in 1882-’83. The current attendance exhibits a subsidiary maximum from 1877-’80 and a minimum in 1882. The curve of accessions shows maxima in 1874, 1879, and 1884. While there are many series of contemporaneous events with which these might be compared,,one only will be considered, namely, the formation of other scientific societies in ‘Washington and the formation of the Mathematical Section within our Society. GENERAI MEETINGS. ou The Anthropological Society was organized February 17, 1879, and has now a membership of 154. The Biological Society was organ- ized December 3, 1880, and has a membership of 174. The Mathe- matical Section of the Philosophical Society held its first meeting March 29, 1883. The Chemical Society was organized January 31, 1884, and now numbers 44 members. During the two years fol- lowing the institution of the Anthropological Society our Society witnessed maxima in the accession to membership, in the total membership, in the attendance, and in the ratio of attendance to membership. During the two years following the foundation of the Biological Society each of these quantities reached or passed a minimum. ‘The year of the organization of the Mathematical Sec- tion was characterized by an increase of attendance, but not of membership. In the four years elapsed since the beginning of the Chemical Society our membership and attendance have steadily increased, their ratio remaining constant. If the relation of our record to the Biological Society only were considered, it would be easy to infer that our Society suffered from the formation of another scientific society, but a contrary inference would be drawn from a comparison of our record with the histories of the Anthropological and Chemical Societies, and in view of all the facts it appears proper to conclude that our membership and attendance have not been materially influenced by the organization of the other societies. The data of attendance have been, classified by months likewise and finally by half-months, with the result which appears in Table II. The data cover a period of 12 years, but are somewhat imper- fect. To diminish the error from imperfection of record, a general correction for annual phase was applied to all the observations— that is to say, they were all reduced to consistency with a mean attendance of 40. Only ordinary meetings for the reading of papers were included, and the year 1887 was omitted because the attend- ance appeared to be greatly affected by the change of quarters (March 26) from the Army Medical Museum to the Assembly Hall of the Cosmos Club. on PHILOSOPHICAL SOCIETY OF WASHINGTON. . TABLE II. Average Attendance at Ordinary Meetings for Hach Half-Month, Compiled from Records for 11 Years, 1875-1886. October, first half =... 39:8; March; first half. 22-2222 eee 6 second half._-. ..-. 40.5 Li second half (eee 40.3 November, first half ------ .--- 45.0 | April, first half .--...-._-.-.. 48.0 ve second half____ -__. 43.9 be second half.2_ = saya 40.3 December)~ first half 2-22 222 -"43°2)|\May, “first half 222" 32s see StS second half._-.--__ 40.8 ts second half____ ____ SEB ee January, — first half _...-.__ 61.6,| June, ‘first half 2... 2c 33.7 st second half__.. ..... 45.9 a second half os ss eneee 28.6 February, first half _--..+--_. 41.3 3 second half ._..-.-. 41.0 In compiling the statistics of papers or communications before the Society, everything has been included which was prepared or announced beforehand, whether offered independently or as part of a symposium, but the remarks of one member upon the communica- tion of another have not been included. The impossibility of other- wise making a consistent distinction has led to the inclusion of every exhibition of apparatus and every reading of a letter upon a scien- tific subject. The biographical memoirs of deceased members which have from time to time been read are included, but not the com- memorative resolutions. The Society has listened in 17 years to 713 papers, as thus de- fined, an average of 42 per year. Six hundred and ninety- two of these have been presented before ordinary meetings, an average of 41 per year. There have been in the same period 277 ordinary meetings, and the average number of papers per meeting has been 2.5. The number of ordinary meetings and the total number of meetings per year were both somewhat greater in the earlier history of the Society than in the later, a tendency having developed to omit one or two meetings in June. There were also more papers read in the earlier years than in the later, and the diminution in papers has been slightly greater than the diminution in the number of meetings, so that the average number of papers per meeting has fallen off from 2.8 to 2.4. For the purpose of exhibiting the subjects which have received the attention of the Society, the entire series of papers has been grouped in ten classes, the discrimination being based on the titles and abstracts, and, to some extent, in the absence of abstract, on the memory of the compiler. Papers belonging properly to two or GENERAL MEETINGS. 33 more of the selected classes have been entered in each, and such duplicate entries have been treated as integers and not as fractions. To an extent dependent on this treatment the deduced ratios are inaccurate. It should be observed that the selection of classes has depended largely on the nature of the material to classify. As the statistics grew out of the work of indexing the Bulletin, the selection was affected by the needs of the indexer, and as it was desired to learn the influence of the organization of other societies on the scope of our proceedings, the selection was affected by the classification of sub- jects among the other societies. The following is the classification: Group 1, Mathematics ; Group 2, Astronomy, including calendars; Group 3, Physics, including molecular physics, electricity, acous- tics, optics, and microscopy, which last subject happens in the litera- ture of the Society to be almost entirely optical; Group 4, Chemis- try and mineralogy ; Group 5, Meteorology and thermometry ; Group 6, Geology ; Group 7, Geography, including physical geography, surveying, and travel and exploration; Gruup 8, Biology, includ- ing zoology, botany, and human anatomy and physiology ; Group 9, Anthropology, including ethnology, archzology, psychology, an- thropometry, political economy, and social science and statistics; Group 10, Miscellaneous, chiefly technology, but including also biography and general philosophy. It will be seen that chemistry, biology, and anthropology are defined so as to include the scopes of the Chemical, Biological, and Anthropological Societies. For convenience of discussion, the period of 17 years covered by the statistics has been divided into five unequal parts, such that three of the lines of separation correspond with the epochs of commence- ment of the three sister societies. The time divisions begin on the years 1871, 1875, 1879, 1881, and 1884, and contain, respectively, 4, 4, 2,3, and 4 years. At the end of the second the Anthropological Society was established, at the end of the third the Biological, at the end of the fourth the Chemical. The Mathematical Section was organized one year before the Chemical Society. For each time division the number of papers of each class was ascertained, and from these numbers were computed the percentages which appear in Table ITI. 49 34 PHILOSOPHICAL SOCIETY OF WASHINGTON. TABLE III. Percentages of Papers on Different Subjects for Different Periods. Periods. 1871 Subjects. to 1871— | 1875- | 1879- | 1881— | 1884- | 1887. 1874. | 1878. | 1880. | 1883. | 1887. 1. Mathematics.____....|. 6 5 2 9 2 5 2) UAstronomiyge see 23 18 18 7 6 16 é:° Physics 2.202 2s 10 14 12 12 9 it 4D \Chemistryieseeasees=s 4 2 6 1 4 3 5. Meteorology -:_-- ---- Y 5 4 13 11 8 6) Geology: 2-22), 2222 6 8 9 14 27 13 i} Geography jest. ae 15 13 7 7 10 11 8: (Biclogy -= ase ena 9 9 10 9 6 8 9. Anthropology ~~. ---- 6 15 19 11 3 12 10. Miscellaneous -___ -__- 12 11 13 Wi 12 13 100 100 100 100 100 100 It appears from this table that in the two periods previous to the organization of the Anthropological Society the subject of anthro- pology furnished first 6 and then 15 per cent. of our material, and in the following periods it furnished 19,11, and 15 per cents. Biol- ogy furnished in the first three periods 9, 9, and 10 per cents., and after the beginning of the Biological Society 9 per cent. and 6 per cent. The percentages of chemistry for the first four periods are 4, 2, 6, and 1, and for the single period of four years since the organization of the Chemical Society, 4. These figures show that the organiza- tion of scientific societies devoting themselves to the cultivation of special scientific fields has not materially affected the interest of our Society in the same sciences, so far as that interest may be judged by the number of communications presented. The table is not arranged to exhibit the effect upon our general meeting of the institution of the Mathematical Section, but an inde- pendent computation has been made with the following result: In 12 years previous to the Mathematical Section the Society listened to 28 mathematical papers, an average of 2.3 per year, In the five years following the general meeting listened to six mathematical papers, an average of 1.2 per year. While the amount of mathe- GENERAL MEETINGS. 39 matics before the Society in general meeting has been greatly dimin- ished, the subject has not been entirely eliminated. The general fact appears to be that the Philosophical Society, being composed partly of men with a wide interest in scientific matters and partly of specialists in many scientific branches, affords a fitting arena for the discussion of subjects of general scientific interest, but is not equally adapted to the presentation of highly specialized researches. By a process of natural and unconscious selection it has discountenanced those papers which from their nature can interest only the devotees of a single science, and it, therefore, has not fully met the needs of the scientific community of Washington. The natural and proper result has been the institu- tion, without and within the Society, of organizations undertaking the cultivation of narrower fields, and these have found material of their own without detraction of material which natually came to us. In anthropology, in biclogy, in chemistry, and in mathematics we still receive the communications which have a broad interest, and, as such papers are largely written from a philosophic point of view, it may well be that we are gainers by the multiplication of organi- zations. But while the modifications which have occurred in the ratios in which various subjects have been represented on the floor of the Society do not indicate an important yielding of our program to outside influence, they do indicate progressive tendencies in other directions. Astronomy, which during the first period was the lead- ing theme, with a percentage of 23, has fallen, through 18, 18, and 7, to 6 per cent.; geography, with 15 per cent. and 13 per cent. for the first two periods, has 7, 7, and 10 for the last three. Geology, on the other hand, with 6 per cent. at first, has increased steadily, through 8, 9, and 14, to 27 per cent., and anthropology and meteor- ology, while exhibiting fluctuations, have on the whole increased their percentages. During the first period astronomy and geography together gave 5 times as many papers as geology; during the last period their combined volume is only two-thirds that of geology. The general explanation is not far to seek. Geology has gained in importance on the floor of the Society because of the rapid growth of the Geological Survey, which has brought to the city and to the Society a large number of geologists. The increased attention of the Society to meteorology is traceable to the establishment of the Study Room of the Weather Bureau, and the increase in anthro- 36 PHILOSOPHICAL SOCIETY OF WASHINGTON. pology is correlated with the growth of the Bureau of Ethnology. The great modification in the relative attention given to different subjects is due to the large amount of new blood acquired by the Society. The statistics of the Mathematical Section are exhibited in the following table: TaBLeE IV. Statisties of the Mathematical Section from its Establishment to 1887. Wapiti ss aoe gs eS eye 1888. | 1884. | 1885. | 1886. | 1887. - Number ofpmectings == As 0 eek 9 6 6 2 12 Number of communications ___-__. ._-.| ~18 11 14 3 20 Average'attendince ls oO Loe se kee. 15 15 15 16 17 Number-ofmemibers) 008 Jo ee 8b 3 41 40 44 The whole number of papers presented to the Society, including those addressed to ordinary and special meetings and to the Mathe- matical Section, has been 786, and they have been communicated by 184 persons. Fifty-seven guests and correspondents of the So- ciety have furnished 67 papers, and 127 members have furnished 719. The total number of persons who have at various times been elected to the Society is 312, and two-fifths of these have contributed something more than remarks to the proceedings. The following numerical data concerning the membership and common membership of the Philosophical and three other scientific societies were derived from what is known as the “Consolidated List of the Philosophical Society,” a list containing the names of the active members of the four societies and the resident members of the Cosmos Club. The list had been corrected to December 1, 1887. In Table V the Anthropological, Biological, Chemical, and Philo- sophical Societies are indicated by the initial letters of their names. GENERAL MEETINGS. 37 TABLE V. Common Membership of Four Societies. Members of | Members of | Members of | Members of all four___-_-__- 3 one only. two only. | three only. ee three only __--__ 34 ce three or more___ 387 Mees FOAL, Bice ae Bs On yn two only -----_- 78 eee LOU WAR C2 2 as VAC Be P28 ss Ores 22) EAC 28 ACO. Bake ‘f two or more -_-- 115 peer (OL enon 22) Ossie. "oO a oneonly 22.3... 293 DB eed Ben 5) Oba cphecag 0, 293 78 34 Total number of persons__ 408 Total memberships. Overlap, by pairs. Nea eee ce eee ee eee ee A, | WAC BS oie ee el ee ee ee AS eee ten aren ee EAE pe eS UTA PAR IC). Eee | es nie Ea ge a a Al Renee SR ee! VAS Ae ee ee UY os Va GD, SE aL ee San Fae at IS 1 LS il 5a ay Se a rents A ene gs) omc (i Se Se et pe Rae OS Eee ee pe eee RL OO, | Com reat as oe Se ee Bu eG INGt bOta he ee eee 408 Difference (due to overlap). 155 Fifty-two per cent. of the members of the Philosophical Society are likewise in one or more of the other societies. The correspond- ing percentages for the other societies are: Chemical, 50; Anthro- pological, 49; Biological, 42. The Cosmos Club has a resident membership of 227, of whom 128, or 56 per cent., belong to one or more of the four societies. 38 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. M. H. DoouirrLeE read a paper ON NEWTON’S VIS, and was followed by Mr. B: Pickman Mann, who read a paper ON REFERENCE INDEXING. [Abstract. ] The author described in part the systems of indexing the litera- ture of science which he had practised for many years, with illus- trative examples and an argument to show their general mie bility and value. He commented upon the extent and variety of the literature of science as a whole, and the impossibility of obtaining a knowl- edge of the literature relating to special departments of research without the aid of indices prepared for the purpose. He then dwelt upon the multitude of separate, partial indices now in ex- istence, upon the difficulties experienced in making use of these indices, and the waste of labor expended in disconnected attempts to obviate these difficulties. He adverted to the advantages which would accrue to all students through co-operative effort to obviate the difficulties described, and remarked upon the necessity, in case such co-operation were to take place, of determining upon a system of carrying it out. He considered the advantages which would be gained for temporary purposes by the combination of existing in- dices into one index to be the property of the co-operators and accessible either directly or mediately to all persons interested. He then passed to a consideration of systems by which indices have been constructed hitherto, and those which should obtain in the formation of such an index as was contemplated here. 309TH MEETING. DerEcEMBER 10, 1887. By courtesy of the trustees of the Columbian University the meeting was held in the law lecture-room of the University building. Invitations to “yourself and friends” to attend the meeting had been mailed to all members of the Anthropological, Biological, and GENERAL MEETINGS. 39 Chemical Societies, and of the Cosmos Club. About one hundred persons were present. Vice-President MALLERY presided. President HARKNEss then presented his annual address, the sub- ject being THE PROGRESS OF SCIENCE AS EXEMPLIFIED IN THE ART OF WEIGHING AND MEASURING. [Printed in full on page xxxvii of this volume. ] A vote of thanks for the address was passed by the audience. 310TH MEETING. DECEMBER 21, 1887. THE SEVENTEENTH ANNUAL MEETING. The President in the Chair. Thirty-eight members present. The minutes of the 294th, 308th, and 309th meetings were read and approved. The President announced the election to and acceptance of mem- bership of Mr. JosepH WILLIAM SPENCER. The annual report of the Secretaries was read and accepted. [Printed in full on pp. Xxx1I, xxxu1I of this volume. ] The annual report of the Treasurer was read and referred to an auditing committee consisting of Messrs. J. 8. Billings, J. C. Well- ing, and C. O. Boutelle. [Treasurer’s report printed in full on pp. XxxIv, xxxv of this volume. ] The Treasurer read the list of members entitled, under Standing Rule 14, to vote at the annual meeting. The constitutional amendment proposed by Mr. Dau at the last annual meeting was adopted by a vote of 26 for to 3 against it. Election of officers was then held. [The result is printed on page xv of this volume. ] The rough minutes of the meeting were then read and the Society adjourned. 1 Wika ape ‘toying « sa) le : st ind f ¢i STW ee! Fe ae A; 4 ihe ae ees ry vey eee RTT, Coen ; phe ee ; + ae ee ee Ba om ie? tnd f es et ee feoaerts Lt k i vy A‘ ; : Coe oie bs on } ia ; wg, ‘ ‘ KM OAs Pipa Ae fm PROCEEDINGS AT A MEETING COMMEMORATIVE OF THE LIFE AND SCIENTIFIC WORK SeRNCERY FULLERTON BAIRD, HELD JANUARY 11, 1888, ANTHROPOLOGICAL, BIOLOGICAL, AND PHILOSOPHICAL SOCIETIES OF WASHINGTON. (41) INTRODUCTION. On August 19, 1887, Spencer FuLieRTon Bairp, Secretary of the Smithsonian Institution, Director of the U. S. National Museum, and U.S. Commissioner of Fish and Fisheries, died at Wood’s Holl, Massachusetts, his post of duty in the last named office. His death at once excited throughout the world feelings and expressions of profound regret. At that time nearly all of his Washington asso- ciates in scientific pursuits were absent from the city, on field duty or in vacation, and were thus unable to jointly testify to the affec- tion and respect in which he was held by them. And especially the scientific societies of Washington, none of which meet during the summer months, were unable to immediately take any action in the matter or to give organized expression to the sentiments of their members. With the resumption of meetings, however, it was determined that such expression should be given with all ceremonial complete- ness, and as the senior of the Washington scientific societies, and the one with which Professor Baird had been most closely con- nected, the Philosophical Society took the initial steps in arranging a joint meeting with the Anthropological and Biological Societies, a meeting which might enable the members and their friends to testify not only their profound respect for this foremost scientific leader, but also their affectionate regard for the man. The appended invitation and programme, which was mailed to all members of the Philosophical, Anthropological, Biological, and Chemical Societies, and of the Cosmos Club, sets forth the form taken in those arrangements : (48) 44 PHILOSOPHICAL SOCIETY OF WASHINGTON. WASHINGTON, January 4, 1888. Sir: The Philosophical Society in conjunction with the other scientific societies of the city will hold a meeting on Wednesday evening, January the eleventh, in commemoration of the life and services to science of the late Spencer Futierton Barrp, Secretary of the Smithsonian Institution, Director of the National Museum, and United States Commissioner of Fish and Fisheries. Members of the societies, and ladies and gentlemen whom they may desire to invite, will assemble in the lecture-room of the Colum- bian University, on the southeast corner of H and Fifteenth streets, at a quarter past eight o’clock. Your presence on this occasion is earnestly desired. C. E. Dutton, RoBERT FLETCHER, J. H. Kipper, Committee of Management. Opening of the meeting, by the President of the Philosophical Society. Professor Baird as Administrator, Mr. W. B. Tayntor, of the Smithsonian Institution. Professor Baird in Science, Mr. W. H. DAtt, President of the Bio- logical Society. The Personal Characteristics of Professor Baird, Mr. J. W. PowELL, President of the Anthropological Society. Mr. Garrick Mauuery, President of the Philosophical Society, called the meeting to order at the time and place above named. RELATIONS BETWEEN PROFESSOR BAIRD AND PARTICIPATING SOCIETIES. By Mr. Garrick MALLERY, President of the Philosophical Society. Lapies AND GENTLEMEN: During several winters before 1871, a club, with commingled social and scientific purposes, used to meet in this city at the houses or its members. 2z>2", and the chance of a particular apple being both rotten and wormy / is =, When # and” are integral the chance is either of or 4 , that gt 2” a When n, 7, w are all infinite, the case of continuous is : . Tw number, this chance is ar Mr. Stone took the ground that the problem is susceptible of but one interpretation, and gave a geometric solution leading to zs for the probability of the compound event. He also gave some in- stances of allied questions in dependent probabilities. : An animated discussion, extending over the remaining time of - the meeting, then followed. Of those who participated in the dis- . cussion, Messrs. CHRISTIE, Curtis, Doouirrye, Exuiorr, Hr11, KUMMELL, STONE and Zrwer considered the problem determinate, while Messrs. BAKER, Harkness, and Woopwarp considered it indeterminate. 90 PHILOSOPHICAL SOCIETY OF WASHINGTON. 27TH MEETING. Marca 30, 1887. The Chairman presided. Present, twelve members and two guests. Mr. R. S. Woopwarp read a paper on THE FREE COOLING OF A HOMOGENEOUS SPHERE INITIALLY HEATED TO A UNIFORM TEMPERATURE. [This paper appeared in full in the Annals of Mathematics. 4°. Char- lottesville, Va. 1887, June; vol. 8, no. 8, pp. 75-88. Also separately printed. ] Remarks were made on this paper by Messrs. KuMMELL, Hi11, and the Chairman. ad Mr. KuMMELL read a paper on THE BRACHISTHODE ON THE HELICOID. [ Abstract. ] The characteristics of this class of curves and the methods of com- puting their lengths in the several cases were explained and dis- cussed. Accurately constructed stereoscopic diagrams of several of — these curves were exhibited. [This paper is expected to appear in the Mathematical Visitor. ] 28TH MEETING. Aprit 138, 1887 The Chairman presided. Present, nineteen members and one guest. Mr. G. W. Hi read a paper on THE MOTION OF HYPERION. Although designed to meet the special case presented by Hyperion, Mr. Hrx1x’s paper treated the general problem of three bodies under the restrictions that they are all nearly in the same plane and that MATHEMATICAL SECTION. 91 the mass of the one whose motion is sought is negligible in compar- ison with the masses of the other two. The potential function for the disturbed body was put in a general form for the purpose of ascertaining the most advantageous variables for its development, and some of the particular forms were derived and discussed. Mr. Hrxt also indicated the methods which might be most advantage- ously followed in the application of his theory to Hyperion. This paper was discussed by Mr. A. Haut, who alluded to the unique character of the motion of Hyperion, and stated some of the more interesting facts concerning the observations of this satellite and the failure of the theories thus far advanced to represent its motion. Other remarks were made by the Chairman and Mr. Woopwarp. [This paper appeared in full in the Annals of Mathematics. 4°. Char- lottesville, Va. 1887, June; vol. 3, no. 8, pp. 65-78. Also separately printed.] Mr. A. Hau presented a paper’ on THE PARALLAX OF @ TAURI. He gave a historical account of the early attempts at the deter- mination of stellar parallax together with some of the results at- ‘tained. He exhibited in tabular form the principal data on which his value for the parallax of «Tauri depends. In contrasting his result with the larger value for the same star determined by SrRUVE he stated that his values for parallax are generally smaller than those of other observers. The brief discussion which followed was participated in by Messrs. Eastman, Pavt, and others. 29TH MEETING. APRIL 27, 1887. The Chairman presided. Present, thirteen members. Mr. A. S. Furnt read a paper on THE MOST PROBABLE VALUE OF THE LATITUDE AND ITS THEORET- ICAL WEIGHT FROM ENTANGLED OBSERVATIONS OCCURRING IN THE USE OF TALCOTT’S METHOD. In this paper Mr. Fun showed first how to express the weighted 92 PHILOSOPHICAL SOCIETY OF WASHINGTON. mean value of the latitude and its weight in the most general case of entanglemept in terms of the results from individual pairs of stars and their symbolical weights. To find the numerical values of these symbolical weights he made use of the principle that the weights of the individual results must be such as to make the probable error of the weighted mean a minimum. After treating the most general case he considered some of the special.cases occur- ring most commonly, and deduced practical formulas for computing the weights of individual results. In illustration of his methods he gave the details of the numerical operations in one of the more com- plex cases presented in actual work. In the discussion which followed, Mr. HArKNeEss derived, by a different and less complex process, some of the formulas given by Mr. Fuint. Others participating in the discussion were Messrs. Pau, FArRquHAR, STONE, and WoopWARD. Mr. E. B. Ex.iorr began the presentation of a paper on THE MUTUAL ACTION OF ELEMENTS OF ELECTRIC CURRENTS. 30TH MEETING. May 11, 1887. The Chairman presided. Present, ten members and two guests. Mr. E. B. Exxiorr continued his paper on THE MUTUAL ACTION OF ELEMENTS OF ELECTRIC CURRENTS. He stated that Ampére’s theory of such currents involves the assumption that the action between the elements is limited in direc- tion to the line joining them. In conformity with this assumption the result reached by Ampére, and now usually given in text books, is that the action is proportional to 4 cos 0 cos 6 — sin @ sin & cos a, in which 6 and @’ are respectively the angles between the directions of the elements and the line joining them, and » is the angle be- tween the two planes defined by the directions of the elements and the line joining them. MATHEMATICAL SECTION. 93 In his own investigation Mr. Exttortr makes no assumption or restriction with reference to the direction of the action of the ele- ments and finds the action proportional to the following expression : (cos 0+ sin @. 7) (cos 0’ + sin 0’ cosw.i+sin@ sinw.7)= cos 9 cos 0’ — sin 6 sin & cos w + (sin @ cos & + cos 0 sin & cos w) t + cos @sin # sinw.j + sin @sin 6 sin w .77. In this expression 0, 6’ and w have the same signification as stated above, and 2, 7 and 7% (or its equivalent &) are quadrantal versors. The first term of this formula represents action in the line joining the elements; the second term represents action in the plane of the connecting line and one of the elements and perpendicular to the connecting line; the third term represents action in a direction at right angles to the plane just mentioned; and the fourth term rep- resents torsion in a plane perpendicular to the connecting line. The actions resulting in some special cases, as when the elements lie in one plane, etc., were explained and discussed. [This paper was presented to the American Association for the Advance- ment of Science at its New York meeting, August, 1887, and appeared in the Electrical World; a weekly review, ete. fol. New York, 1887, Au- gust 27; vol. 10, no. 9, p. 116. Also separately printed. ] Mr. Hit, following Maxwell, gave some of the principal steps in the process which leads to Ampére’s result, indicating that that process differs from Mr. Exuiort’s in leaving out of account cer- tain couples and in assuming a certain undetermined quantity to be zero. The paper was further discussed by Mr. Harkness, the Chair- man, and others. Mr. Doo.irrLe began the presentation of a paper on ASSOCIATION RATIOS. 94 PHILOSOPHICAL SOCIETY OF WASHINGTON, 3lst MEETING. May 25, 1887. The Chairman presided. Present, sixteen members and one guest. Mr. M. H. Doo.irr.e continued his paper on ASSOCIATION RATIOS, which consisted chiefly in a review and criticism of an article* by Mr. G. K. Ginsert on Finley’s Tornado Predictions. The follow- ing is an abstract of Mr. DooLrrre’s paper: By Mr. GILBeERt’s notation: s = whole number of predictions. p = number of positive predictions. o = number of occurrences. = number of verifications of positive predictions. p' =s8— p= number of negative predictions. o' =s —o = number of non-occcurrences. o —c= “measure of the failure in inclusion.” p—c= “measure of the failure in exclusion.” We should also have for consistency c= measure of success in inclusion. ce =s—o—p-+c= measire of success in exclusion. He says, “If inclusion and exclusion are equally important their measures bear the same weights.” This is as true for success as for failure, but Mr. GILBERT gives to the measure of success in exclusion no weight whatever, and entirely disregards it. He has o + p — 2c = measure of the general failure of prediction. We should also have 3—o—p-+ 2c= measure of the general success in prediction. The latter measure consists of the “favorable cases;” the former * American Meteorological Journal. 8°. Detroit, Mich., 1884, Sep- tember; vol. 1, no. 5, pp. 166-172. MATHEMATICAL SECTION. 95 of the “unfavorable ;” and the “ratio of verification (the favorable cases divided by the sum of the favorable and unfavorable,” becomes Sip On ae —_ 8 v= And this is Mr, Frnuey’s method of computation. Mr. GrLBERT then employs a process to which he gives no name, but which may be called the elimination of hypothetical chance. : ) Pa ie ae sa . He estimates that e verifications of positive predictions might have been expected if the same number of positive predictions had been made at random, and sets these cases aside as ot neither discrimination nor want of it. In effect, he subtracts 22 © from each of the quantities 0, p, and ¢, and proceeds with the wees This portion of his reasoning is regarded as sound, and the process may be applied with great bn to properly formed ratios. The ratio v is c ay vay e+ c a ?p ra pr To eliminate hypothetical chance, “E should be subtracted from each of the quantities ¢ and p, ¢ and ©? Cage é and p’. Denoting the result by @, ee ie a OD. 4 2 (es — op) ~ p(s—0) +0(s—p) When p= 100, o= 51, c= 28, s = 2808; then p = 27038, = 2752, é= 2680 ; and __ 26°18 + 26:18 355. ~ 98:18 + 49° Ag The above formula, like many others, successfully passes all the tests which Mr. Gilbert devised for his own formula, but it fails Ss 96 PHILOSOPHICAL SOCIETY OF WASHINGTON. under others, and it is not maintained that it has any scientific value. . Mr. Gilbert says that he hopes “to show that Mr. Finley’s method involves a serious fallacy. This fallacy consists in the assumption that verifications of a rare event may be classed with verifications of the predictions of frequent events without any system of weight- ing.” It is not perceived that Mr. Gilbert has furnished any such system. The fallacy, perhaps, consists rather in the supposition that any valuable result can be obtained by averaging the percent- ages of verification of heterogeneous classes of predictions. Mr, Finley correctly computed his indiscriminate percentage of verifi- cation, and thereby furnished a striking and, perhaps, much-needed illustration of the’ worthlessness of such computations. The elimi- nation of hypothetical chance from such mixed percentages merely renders their worthlessness less apparent. This paper was briefly discussed by Messrs, Curtis, FARQUHAR Hitt, Baker, and Woopwarp. Mr. H. FarquHar presented a solution and generalization of a problem, proposed in Science,* requiring the division of a rectangle, by asingle step-cut, into two parts which when put together will form a square. Mr. Marcus Baker presented a communication on A COLLECTION OF SOLUTIONS OF THE TRISECTION PROBLEM. [ Abstract. ] The communication consisted of an informal statement from notes and memoranda of progress in the direction of an exhaustive col- lection of real solutions of the problem to trisect an angle. It was pointed out that, though the problem was a very old and very famous one, energy is constantly wasted in its study by those igno- rant of what has been done, and that this misdirected energy might, in large part, be due to the want of any satisfactory digest of results hitherto attained. The author had himself felt the need of such a digest, and, finding none, had some years ago begun a collection of *See Science. 4°. New York, 1887, May 20; vol. 9, no. 224, p. 488, query 5 a MATHEMATICAL SECTION. 97 notes and memoranda, with a view to the preparation of a fairly complete collection of solutions of the problem and the preparation of a bibliography. Progress in the work had been slow, and the results are still very incomplete, especially the bibliographic part, which was deemed the most important. The present collection of notes contained about a dozen different solutions of the problem and a suggested classification for a digest of the subject as follows: . Historical Introduction. . Trisection by the conic sections. . Trisection by special or higher curves. . Trisection by mechanical devices. . Trisection by approximation. . False trisections. . Bibliography. NAnooarh Wh re Of the trisections by the conic sections five were enumerated, viz: 1. By parabola and circle. 2. By parabola and parabola. 3. By parabola and hyperbola. 4, By the equilateral hyperbola. 5. By the hyperbola, whose asymptotes form an angle of 120°. Trisections by the following curves were also enumerated : 1. Conchoid of Nicomedes. 2. Conchoid on circular base = trisectrix = planetary curve of ~ Ptolemy = special case of limagon of Pascal. 3. Cycloid. 4, Epicycloid or trochoid. 5. Quadratrix of Dinostratus or Hippias of Elis, 6. Quadratrix of Tschirnhausen. 7. Spiral of Archimedes. Respecting the cissoid of Diocles, it was remarked that no solu- tion of the trisection problem, by its aid, had been found. Also respecting the cycloid, which Sir Isaac Newton is said to state may be used to trisect an angle, no solution by means of it had been found, but the author had himself made one recently. 53 98 PHILOSOPHICAL SOCIETY OF WASHINGTON. Of the various mechanical devices used for trisection the linkage of Thomas of Ceva was given, others being referredeto only. Of false trisections, the number was stated to be very large and of unequal value, some giving close approximations and others failing ignominiously. Finally, in the bibliography, now containing some fifty references, and believed to be only the beginning of a reason- ably full list, it was proposed to make an authors’ catalogue of en- tries, and to follow each reference with a very brief characterization of the contents of the article. The foregoing scheme had beet laid out but latterly had made no progress, and the opinion of the section was sought as to the desira- bility or advisability of carrying the work on. Mr. Curtis made the following remarks: Six or eight years ago I began a similar collection of trisection methods, in looking over which I find a number of solutions addi- tional to those presented by Mr. Baker. The following six belong to the class in which an angle is trisected by means of curves : (1) y+ ay — azy + bx? =0; the ophiuride of Dietrich Uhlhorn (1764-1837). (2a? — yp)? . (2) Ae 4a? — y 4 the polyode of Dr. Wm. Hillhouse,* Prof. J. W. Nicholson,} J. Bruen Miller.t (3) Ao? + 12y?=(VY1—a? + 9) — 8y V1 — +4. Dr. Wm. Hillhouse. (4) [Curve drawn, but equation not given. ] Ibid. *The Analyst; edited and published by J. E. Hendricks. 8°. Des Moines, Iowa. 1882, November, vol. 9, no. 6, pp. 181-:84. See also same, 1876, September, vol. 3, no. 5, p. 151. ft Same. 1888, March, vol. 10, no. 2, pp. 41-48. See also The Multisector and Polyode. By Prof. J. W. Nicholson, M. A., Professor of Mathematics. Louisiana State University. 8°. New Orleans; published at the Times- Democrat. 14 pp. ${ Van Nostrand’s Engineering Magazine. 8°. New York, D. Van Nos- trand, 1880, March, vol. 22, no. 135, pp. 206-209. MATHEMATICAL SECTION. 99 2 {=A\?2 © av (ot 4) 1 “+ (Vim +¥3—y) Thad. (6) w+ (8y— 4y°)? =r” Ibid. Dr. William Hillhouse, of New Haven, has not only shown that the last five curves may be used for trisecting an angle, but has devised instruments for describing them. This latter step, as I view the problem of trisection, is a necessary part of any real solu- tion by means of curves. The simple determination of the equations that will satisfy the analytical conditions of trisection, without the instrumental means for describing the curves, does not constitute a solution of the problem. It is essentially something to be done, not something merely to be proved, and its fame arises from the im- possibility of making the trisection of an angle by means of a ruler and pair of compasses. Any proposed solution, therefore, must in- dicate a geometrical instrument for accomplishing it, and the nature of the motion applied therein determines the character of the solu- tion. A class of solutions, regarded the most elegant of all, is that in which link machines trisect the angle directly, without the aid of interposed curves. Of this class I have found three instruments, invented respectively by the Marquis de |’Hépital (1661-1704), A. B. Kempe, and Professor Sylvester. That of |’Hépital is a com- bination of link and sliding motion ; those of Kempe and Sylvester are pure linkages. With respect to the two latter, I wish to call attention to the elementary character of the solution. Euclid’s postulates require us to be able to draw a straight line and a circle, and it is frequently assumed that they imply the use of a straight- edge and a pair of compasses. But, manifestly, any other instru- ments that can describe the circle and the straight line satisfy equally the requirements of the postulates. Moreover, the use of a straight edge assumes as accomplished the very thing proposed to be done; whence the straight-edge is not an original instrument for describing a straight line. Such an instrument is given by the linkage of Peaucellier. More originally, therefore, than by the straight-edge, the postulates of Euclid may be assumed to imply the use of pure link motion. Wherefore, if pure link motion be considered as postulated by Euclidian geometry, the trisection of an angle becomes one of the simplest of geometrical problems. 100 PHILOSOPHICAL SOCIETY OF WASHINGTON. Mr. KumMMeE LL remarked that the supposed analogy between the duplication of a cube and the trisection of an angle does not exist, since the latter requires a cubic with three real roots, while the former requires a cubic having one real and two imaginary roots. The subject was further discussed briefly by the Chairman and Mr. Bates. 32D MEETING. OcToBER 19, 1887. The Chairman presided. Present, sixteen members and one guest. Mr. G. W. Hix read a paper on THE INTEGRATION OF DIFFERENTIAL EQUATIONS ADMITTING PE- RIODIC INTEGRALS. [ Abstract. ] The independent variable being conceived as time, a system of ordinary differential equations may be said to admit periodic inte- crals when the values of the dependent variables, either exactly or with an approximate tendency, after a certain lapse of time, repeat their series of values. In the latter case the longer the lapse is made the more nearly is the repetition brought about. Strange as it may seem, this subject, except in the case of simply periodic inte- grals, is, at present, not completely understood. The text-books on differential equations are almost wholly engaged with the cases, which, by certain artifices, can be integrated in finite terms or re- duced to quadratures. In the treatment of physical problems, however, we seldom meet with equations of this class.) Far more frequently it is found that methods of approximation must be re- sorted to. Cauchy appears to be the author who has done the most for the elucidation of this part of the subject. His memoirs are in his later Exercises and in the volumes of the Comptes Rendus for 1856 and 1857. In this paper the mode in which simply periodic integrals arise was discussed, and the theory afterwards illustrated by treating the following problem: Find the conditions of motion of any number of material points mov- MATHEMATICAL SECTION. 101 ing about a centre under the action of central forces whose potential is a function of the sum of the squares of the radii vectores. The differential equations of this problem, in the case where the radii are supposed to describe no areas, were first integrated by Binet.* But the addition to the forces of the terms arising from cen- trifugal action much enhances the interest of the problem. The chief point of interest brought out by the solution was that while the directions of the points, whether as seen from the centre or from each other, all return to the same values after the lapse of a certain time, as do also the ratios of the radii vectores, the absolute values of the latter have all a factor whose period is generally dif- ferent from the former. Thus the movement of the system may be conceived as taking place under the operation of two distinct causes, viz: the first producing a revolution of all the points about the centre in closed curves in the same time, while the second, having a different period, changes the scale of representation of the system in space. [This paper appeared in full in the Annals of Mathematics. 4°. Char- lottesville, Va. 1887, October; vol. 3, no. 5, pp. 145-153. ] Mr, H1w’s paper was briefly discussed by Mr. A. Haru and the Chairman. Mr. A. HAut read a paper on EULER'S THEOREM (GENERALLY CALLED LAMBERT’S). [Abstract. ] This theorem is well known to astronomers and is very useful in computing the orbits of comets. The time of the passage of the comet from one point to another of its orbit is expressed by means of the two radii vectores drawn to the points, and the chord joining these points. For many years, and by miny writers even of the present time, this theorem is attributed to Lambert. Mr. Haru stated that it was first given by Euler about 1743. He gives two proofs for the parabola, and then extends the theorem to the ellipse. For this case Euler gives first an expression for the peri- helion distance in terms of the sum of the two radii vectores and the chord. He then gives an approximate expression for the time of describing the are in terms of the perihelion distance, the radii * Journal de mathématiques; par J. Liouville. 4°. Paris, 1837. 1st series, vol. 2, p. 457. 102 PHILOSOPHICAL SOCIETY OF WASHINGTON. vectores and the eccentricity of the ellipse, and directs us to sub- stitute the value of the perihelion distance. Euler does not, there- fore, give an explicit expression for the time in terms of the radii vectores and the chord, although he points out how this may be done. Considering the results that he obtained, Mr. HAut thinks that this theorem, with respect to all the conic sections, should be known by the name of Euler. Remarks on this communication’ were made by Messrs. Hr.1, Strong, and WINLOCK. 33D MEETING NOVEMBER 2, 1887. The Chairman presided. Present, fifteen members and one guest. Mr. E. B. Etuiorr gave a brief description of a new form of com- puting machine, which prints and arranges in the usual form for addition any series of numbers and then prints their sum, the work of the operator being merely mechanical as in the use of the type- writer. Although designed especially for performing and printing work in addition, the machine may also be used for multiplication and division. Mr. Wm. HArKNEss presented a paper on THE CONSTANT P IN OBSERVATIONS OF TERRESTRIAL MAGNETISM. It was explained that this paper arose from a correspondence in Nature concerning the modes of computing the constant. In a letter published in the number of that journal for August 18th, 1887, Mr. Harkness referred to an expression for P given in Stewart and Gee’s Practical Physics, and suggested a more convenient form for logarithmic computation. In the number for September 8th, Mr. William Ellis gave another but somewhat less accurate expression for the computation of P; and in the number for September 29th, Prof. Arthur W. Riicker gave what he considered a more accurate expression than either of the others. Starting from the fundamental equations of Gauss, Mr. Harx- NEss derived a formula for P correct to terms of the second order inclusive. He then showed that Riicker’s formula, which pur- MATHEMATICAL SECTION. 103 ported to give terms of the second order, was incorrect, and pointed out that the error in Riicker’s process consisted in expanding to terms of the second order an expression which included only terms of the first order. This paper was briefly discussed by Messrs. Hatt, ABBE, Kum- MELL, and HARKNEsS. This and other related papers appeared in Nature.* Mr. R. 8. Woopwarp read a paper on THE CONDITIONED COOLING OF A HOMOGENEOUS SPHERE. The salient features only of this paper were presented. The funda- mental assumptions and analytical conditions of the problem were indicated, and especial attention was directed to the distinction be- tween the case of “conditioned cooling” and that of “free cooling,” which latter was discussed by the author, at the 27th meeting of the section. It was shown that the solution for the more complex case of “conditioned cooling” is derivable by a comparatively simple process from the solution for “free cooling.” The probable discrep- ancy between the data presented by the earth as a cooling sphere and those assumed in the solution of the problem, and the additional data requisite for a more complete solution were pointed out. The presentation of the paper was followed by an informal dis- cussion participated in by nearly all present. This discussion re- ferred chiefly to the physical features of the earth as a cooling sphere, and served to disclose a diversity of opinion concerning the con- ductive and convective properties of such large masses. [This paper appeared in full in the Annals of Mathematics. 4°. Char- lottesville, Va. 1887, October; vol. 3, no. 5, pp. 129-144.] o * Nature, a weekly illustrated journal of science. 4°. London, 1887-1888. 1887, Aug. 18, vol. 36, no. 929, p. 366. Ontheconstant P; by Wm. Harkness. Sept. 8, vol. 36, no. 932, p. 436. Same; by Wm. Ellis. Sept. 29, vol. 36, no. 935, p. 508. Same; by A. W. Ricker. Dec. 8, vol. 37, no. 945, pp. 127-128. Same; by Harkness and re- joinder by Ricker. 1888, Jan. 19, vol. 37, no. 951, pp. 272-273. Same; by Harkness and re- joinder by Rucker. 104 PHILOSOPHICAL SOCIETY OF WASHINGTON. 34TH MEETING. NoveMBER 16, 1887. The Chairman presided. Present, ten members. Mr. Ormonp STonE read a paper on THE ORBIT OF HYPERION. [Abstract. ] The principal difficulty in the integration of the equations of motion in the case of the problem of three bodies arises in the integration of terms involving the inverse powers of the distances between the dis- turbed and disturbing bodies. When the ratio between the radius vectors is not too near unity, the inverse powers referred to can be developed in rapidly converging series in terms of cosines of multiples of the elongation. When, however, these ratios do not differ greatly from unity the convergence of the series mentioned is very slow. If, in addition, the mean motions of the two bodies are nearly com- mensurate, the ordinary methods of solving the problem become in- applicable. Such a case presents itself in the determination of the perturba- tions of Hyperion produced by Titan. On the other hand the mutual inclination of the orbits of these satellites is so small as to have eluded detection ; the eccentricity of the orbit of Titan is less. than 0.03, and the position of the aposaturnium of Hyperion so nearly coincides, at least at present, with the point of conjunction of the two satellites as to give rise to a suspicion that the eccentricity of its orbit is, in reality, small, and that the apparent eccentricity is principally due to the perturbations produced by Titan. In view of these circumstances, that part of the disturbance has been investigated, which may be determined by neglecfing the mutual inclination and the eccentricities of the orbits of both bodies, reserv- ing a discussion of the remaining portion for another paper. It was accordingly assumed that r=a(1+a,cosd+a, cos20+...), oe = n(n, cos 9-+ n, cos 20+ ...); where r and w are the radius vector and longitude in orbit of Hype- rion, @ is the mean angular distance between the radius vectors of MATHEMATICAL SECTION. 105 Titan and Hyperion, a and n are the mean values of r and w, and a,, n,, etc., are constants to be determined. In the differential equa- tions of motion for r and w, those terms not containing explicitly the mass of Titan were expanded by Taylor’s theorem into series of sums of terms containing cosines of multiples of @ affected with con- stant coefficients; while the terms containing the mass of Titan ex- plicitly were expanded mechanically into a series of cosines of mul- tiples of @ by means of assumed values of the coefficients. Equating the coefficients of the cosines of equal multiples of 0, a number of equations were obtained from which to derive a corresponding num- ber of the quantities a,, ,, etc. With these new values were ob- tained and the process repeated. Instead, however, of considering m’ (the mass of Titan) as known, a, was assumed to be given and m’ was considered as one of the unknowns. [This paper appeared in full in the Annals of Mathematics. 4°. Char- lottesville, Va., 1887. Vol. 8, No. 6, p. 161.] Brief remarks on. Mr. Stonn’s communication were made by the Chairman and by Messrs. Bakrr, H1Lu, and KuMMELL. Mr. E. B. Exxiorr presented a paper on THE QUOTIENTS OF SPACE-DIRECTED LINES. He wrote down some of the fundamental relations of this analy- sis and explained the nature and properties of the special symbols employed. He called attention to the lectures of Hamilton on quaternions, and to his “letters” on the same subject, as they ap- pear in Nichol’s Cyclopedia ;* and commented on the transition from Hamilton’s primary conception of a quarternion as a quotient of two directed right lines in space to his secondary conception of a quaternion as the sum of a directed right line and a number. The presentation of this paper was followed by a discussion, in which Messrs. BAKER, H1Lu, Sronr, Woopwarb, and the Chair- man participated. * See A cyclopedia of the physical sciences, ete., by J. P. Nichol. * * 8°. London and Glasgow, 1857. pp. 625-628. 106 PHILOSOPHICAL SOCIETY OF WASHINGTON. 35TH MEETING. NOVEMBER 30, 1887. The Chairman presided. ry Eleven members present. Mr. E. B. Exxiorr continued his remarks, begun at the last meeting, on THE QUOTIENTS OF SPACE-DIRECTED LINES. [Abstract. ] Mr. Exxiorr said that the quotient of two space-directed lines is not a line, but is abstract. It is a quantity which applied as a mul- tiplier to one of the space-directed lines will produce the other. He then gave as an illustration of this principle its application to the problem of the mutual action of the elements of electric currents. Let » and »’ represent, respectively, in length, current strength, and direction, two elements of electric currents. p and p’ represent, respectively, in length and direction, the lines connecting the centers of the elements. 6 represent the angle made by the element » with the line connecting the elements » and wv’; that is, with p. ¢ represent the angle made by the element /’ with its rectan- gular projection in the primary plane; that is, the plane determined by the element » and the connecting line p. ¢ represent the angle made in the primary plane by the rec- tangular projection of the element »’ and the connecting line p’. The effect of the action of » on yp’ will be as the product of the current strength, the length, and the direction of the elements, and inversely as the square of the distance, and the direction of the ac- tion will be expressed “by the following formula: utxu4 = cos 0 cos / cos gy — sin 0 cos ¥ sin ¢ + [cos @ cos ¢ sin g + sin @ cos ¢ cos g]% + cos@sin¢.9 + sinésing.y; ~ in which the first line denotes action (transference) in the direction of the line connecting the centers of the elements; the second line MATHEMATICAL SECTION. 107 denotes action (transference) in the primary plane, but perpendic- ular to the direction of the connecting line; the third line denotes the actgn (transference) perpendicular to the connecting line in a plane perpendicular to the primary plane; the fourth line denotes action (torsion) in a plane perpendicular to the primary plane. If instead of the angles ¢ and ¢ the angles # and w are used, denoting the angle made by »’, with the line connecting the centers of the elements, that is, with p’; and w denoting the angle which the plane of y’ and p’ makes with the plane of » and p, the direction of the resulting action will be expressed by the following formula: See us = cos cos ’— sin @ sin @ cos w + [sin @ cos &’+ cos @ sin @ cos w]i + cos@ sin sinw .j + sin @ sin sinw . i. The values of the four parts of this formula are identical, respect- ively, with the corresponding parts of the former one. The mutual action of the unit-right- quotients (or quadrantal versors) 2,7 and 77 are such that ? = —1; 7?= —1; and ri (or its substitute k*) = —1, from which it readily appears that 7=h= — ji; jk=i=—ki; and ki=j = — ik. Brief remarks on Mr. Etuiorr’s paper were made by the Chair- man and by Mr. CuristTIE. Mr. ArremMAs Martin presented a paper on METHODS OF FINDING N™-POWER NUMBERS WHOSE SUM IS AN N"™-POWER; WITH EXAMPLES. [ Abstract. ] First method: Let 17+ 27+ 374+ 474+ 1. Le = 8 and assume the auxiliary formula GD. SS Orie ts e1 va Ey also assume d such that whence Seep (pF gee oh 2) 108 PHILOSOPHICAL SOCIETY OF WASHINGTON. The solution now consists in determining by trial whether d can be separated into n”-power numbers, all different.» Second method: r In equation (1) a may sometimes be separated by trial into n*-power numbers, all different. Third method: Assuming b” nearly equal to but less than S, ,, and putting r for the difference, we have Saeed a Me : y (3) In formula (1) p and q may be any numbers chosen at pleasure. In formula (2) x should be chosen equal to or greater than the number of powers sought, and p and q any numbers that will give d positive, provided p be not less than z. In formula (3) 6 must be greater than a. Formulse (1) and (2) are taken from Dr, Hart* who has treated the cases of squares and cubes at some length. Formula (8) is found to be especially serviceable if a large number of powers is sought. Examples.—The values of S., , for n = 2, 3, 4, and 5, respectively, are here set down for reference’ as follows : Sot ee @t) Qe+)); x, S ,=42(@+); S,4= 30% (62*+ 152°+ 102°—1); 8, p= te? w+ 1)? (22*+ 2a —1). 22 Ex. 1. Using formula (2) assume «= 5, p= 6, and q=1. Then d= 42, which by trial is found equal to 1?+ 47+ 5’, whence ?+3?+6=7*. *See The Mathematical Magazine. Edited and published by Artemas Martin. 4°. Erie, Pa. 1882-1884. Vol.1, No.1 seta 1882], pp. 8-9, and No. 11 [July, 1884], pp. 173-176. Ex. 4. II. n=3: Ez. 1. Ex. 2. Ex. 3. Ill. n= 4: Ex. 1. MATHEMATICAL SECTION. 109 . Using formula (1) assume p = 8 and gq = 38; whence a = 57, which is by trial found equal to 17+ 2?-+ 47+. 6? and 1+ 2?+ 47+ 67+ 8? =117, . Using formula (3) assume z = 50 and 6 = 206; then 7 = 489, which by trial is found equal to 1? + 2? + 22 or 5?+ 8?-+ 20, etc.; whence we have two sets of 47 numbers, the sum of whose squares is a square, Using formula (3) assume z= 100 and 6=1750; then r = 2850, which by trial is found to equal 4? 5?-++ 53?; whence V+ 2+ 34+ 6477+... + 52’ 547+... . +100°=1750? Using formula (2) assume «= 5, p= 5, g=1, whence d = 134, which by trial is found equal to 1°+ 2°-+ 5%, whence 3+ 44 53 = 6% Using formula (1) assume p =8, g =1, whence a =217, which by trial is found to equal 1°+ 6°; hence 13+ 33+ 48+ 58+ 8 = 9, Using formula (3) assume «= 100 and b= 294; whence 7 = 90 316, which by trial is found to equal 1°-+ 6+ 11°-+ 21°+ 43°, whence J+ ..5+774+ ..10°4+12%4+ .. 20° + 228+ .. 42?+ 444. . + 100° = 294°. . Using formula (3) assume «=1000 and 6= 6303; whence r= 5 869 873, which by trial is. found to equal 1° + 2° + 10°-+ 16° + 32°+ 180°; hence, a+ ..9+11°5+ ..15+174.. 313+ 33°-+ .. 1797+ 181° + . . 1000°= 6303%. Using formula (2) assume e=10, p=14, and q=1; whence d = 13 124, which by trial is found equal to “144+ 2+ 3+ 5'+ 7+ 10*, whence 4* + 6+ 8*-++ 9+ 14*= 15+, 110 PHILOSOPHICAL SOCIETY OF WASHINGTON. Ex. 2. Using formula (3) assume «= 100 and 6 = 212; whence r = 30370194, which by*trial is found equal to 1*-+ 2+ 3*-+ 44+ 8+ 10*+ 14*+ 24*-+ 4244721; hence if all the natural numbers from 1 to 100, ex- cept the ten above given, be raised to the fourth power and added, their sum equals 212*. Be is) aa / Ex. 1. Using formula (2) assume = 10, p=11, and q=1; whence d = 133 044, which by trial is found to equal 15+ 2°+ 3°+ 8+ 10°, and therefore 445+ 6+7+ 99+ 11? = 12°. Ex. 2. Using formula (1) assume p = 29 and g=1; whence a = 3788851, which by trial is found equal to 5°>+10°+ 11°+ 16°-+ 19°; hence 5+ 10°-+ 11° + 16°+ 19° + 29° = 30°. Ex. 3. Using formula (2) assume «=18, p=31, q=1; whence d= 1 731 920, which by trial is found to equal 1°+2°-+ 4°-++ 5°+ 9°+12°+17°, and therefore 3+6+ 77+ 8+10°+11°+ 13°+ 14° + 15° + 16°+ 18° + 31° = 32°. In finding these numbers, use has been made of Barlow’s tables of fourth and fifth powers. To further facilitate the work the values of Sz,n for n=4 and n= 5 were tabulated. This paper was discussed briefly by the Chairman and by Messrs. DoouirrLe, Hitt, BAKER, and KUMMELL. NOTE. The following members have assisted the Chairman and Secretary in the examination of abstracts of communications to the Mathe- matical Section: Title. Author. Third member. Association ratios. M. H. Doolittle. G. K. Gilbert. A collection of solutions of the Marcus Baker. + a . Asaph Hall. trisection problem. G, E. Curtis. The orbit of Hyperion. Ormond Stone. Asaph Hall. Methods of finding x*b-power Artemas Martin. Marcus Baker. numbers whose sum is an 2th power. (111) NOTE ON THE PUBLICATIONS OF THE SOCIETY. The ten volumes of the bulletin now issued cover the proceedings of the Society from its organization in March, 1871, to the end of December, 1887, a period of 17 years. Volumes 1 to 3 of the Bulletin apply to irregular periods; volume 4 gives the proceedings for a Society’s year, beginning in October of one calendar year and end- ing in June of the next. In 1882, the Society’s year was changed to coincidence with the calendar year, and volume 5 contains the minutes from October, 1881, to December, 1882, inclusive. Volumes 6 to 10 cover, respectively, the calendar years 1883-1887. The pages of all the volumes have been stereotyped at the expense of the Smithsonian Institution, and after the Society’s edition, usually of 500 copies, has been printed, the plates have gone into the cus- tody of the Institution, which has subsequently issued an edition of its own, constituting a paper of its Miscellaneous Collections. In the Smithsonian edition, volumes 1, 2, and 3 of the Bulletin consti- tute volume 20 of the Miscellaneous Collections, and volumes 4 and 5 constitute part of volume 25 of the Miscellaneous Collections, Volumes 6 to 8 have been reprinted by the Institution, but not yet gathered into a Collections volume for binding. Their numbers in the Smithsonian list are as follows: ae. 8 et ee ROP A O48 Ie ge ne. eee ee Oe Oh Go a 6 sw es as cae NO Gao The Smithsonian edition is in the main typographically identical with the Society’s edition, but the following differences are to be noted. Volume 20 of the Smithsoniau Collections contains, in addition, the following title page and contents: Smithsonian Miscellaneous Collections. Vol. XX. (Vignette and motto.) Washington: Published by the Smithsonian Institution. 1881. Contents. Article I. Bulletin of the Philosophical Society of Washington. Vol. I, March, 1871, to June, 1874. Pp. 218. 54 (118) 114 PHILOSOPHICAL SOCIETY OF WASHINGTON. Article II. Bulletin of the Philosophical Society of Washington. Vol. II, October 10, 1874, to November 2, 1878. Pp. 452. Article III. Bulletin of the Philosophical Society of Washington. Vol. III, November 9, 1878, to June 19, 1880. Pp. 169. The plates for this volume were changed by way of correction in a number of details, and the following list of differences may be re- garded as corrigenda for volumes 1, 2, and 3 of the Society’s edition. Page. 51 38 54 57 57 57 DIFFERENCES IN VOLUME I oF BULLETIN. Tine. iT 12 38 Society's edition. Benj. F. Pierce 34, 35 B. F. Taylor erosions particles, is a minimum marl-gravel sufficed, west, water, o. London Glaishen J. K. Gilbert Division Raibal Plateau Sandstones 87 Smithsonian edition. Benj. Pierce 36, 37 W. B. Taylor erosion particles is at a minimum marl, gravel sufficed west water of London Glaisher G. K. Gilbert division Kaibab Plateau Sandstone 89 DIFFERENCES IN VOLUME II or BULLETIN. Line. 31 Society’s edition. Carl Cripsey 00279 among the Esquimaux tribes by A. H. Spofford * Appendix. Smithsonian edition. Karl Crissey 00729 resulting from gram- matical A. R. Spofford MATHEMATICAL SECTION. 115 Line. Society’s edition. 22 Dalton 16 Meyer 2 EK. K. Gilbert 7 September 2 E.K. Gilbert 18 E. K. Gilbert 2 Charles C. Boerner 7 Whyte 15 B.A. Alvord 8 Espey . 30 Whyte 6 M.B. Meek 16 “The Henry Mountains,” 22 ~2B.F. Green 30 Greene 15 Woowdard 27 Henry Parker last great, that 388 Martin 9 Cox 3. J. W. Clark 24 Gallandet 10 La Verrier’s 2 Observations 12 Esquimaux Smithsonian edition. Dutton Mayer G. K. Gilbert September. G. K. Gilbert G. K. Gilbert Charles G. Boerner White B. Alvord Espy White F. B. Meek The Henry Mountains, B. F. Greene Green Woodward Henry, Parker great that Martyn Coues F. W. Clark Gallaudet Le Verrier’s Observatories the extension of DIFFERENCES IN VOLUME III or BULLETIN. Line. Society’s edition. 2 I-XV 4 David B. Todd 8 Icthys 12 Phosphhorescent 387 base 36 G. W. Osborne 56 foot note Smithsonian edition. i-xv David P. Todd Tethys Phosphorescent bases J. W. Osborne In the above diagram, the symbol oc should be a, and oc// 2 should be a// 2. 116 Page. 57 58 58 PHILOSOPHICAL SOCIETY OF WASHINGTON. Line. 17 9 14 59 foot note 117 120 124 195 126 126 127 127 156 159 164 165 168 168 168 168 168 169 169 30 Society’s edition. 0.49788, 15817, 54736. b? Ta m Nevada Michaelson Alfred G. W. Osborne carboniferous to and in consequence of when known miocene Nicholas Instition Hoarlem R. Craig Aztic A. Michelson 119 and 147 G. W. Osborne S. W. Powell C. S. Schott L. L. Woodward Smithsonian edition. 0.49788 15817 54736. 2 i in In this page and the fol- lowing, the symbol 7 (for radius) should read r. Wyoming Michelson Albert J. W. Osborne Carboniferous streams, which result from as far as known Miocene Nichols Institution Haarlem T. Craig Aztec A. A. Michelson 119 and 148 J. W. Osborne J. W. Powell C. A. Schott J. J. Woodward Volume 25 of the Smithsonian Collections has the following title- page and contents. Smithsonian Miscellaneous Collections. Vol. XXV. (Vignette and motto.) Washington: Published by the Smithsonian Institu- tion. 1883. Table of Contents. Article I. (498.) Bulletin of the Philosophical Society of Wash- ington. Vol. IV. October 9, 1880, to June 11,1881. 1883. Pp. 189. Article II. Washington. 1883. Pp. 189. (503.) Bulletin of the Philosophical Society of Vol. V. October 8, 1881, to December 16, 1882. INDEX TO VOLUMES. I-X. Volume, Roman pagination, Arabic pagination, and pagination of appendix are distinguished thus: ix, xvi, 23, (17). The pages of appendices are differently numbered at top and at bottom; the pagination at bottom. the index refers to The titles of all papers read to the Society are entered (with some duplication) under the following words: Acoustics, Anatomy, Anthropology, Archeology, Astronomy, Biography, Biology, Botany, Calendars, Chemistry, Electricity, Geography, Geology, Mathematics, Meteorology, Mi- croscopy, Mineralogy, Miscellaneous, Oceanography, Optics, Physics, Political Economy, Psychol- ogy, Seismology, Social Science, Thermometry, Zoology. Page. Abbe, Cleveland, communication on the aerial currents observed in balloon as- GENSIONS,. ADSt7 ACT ..ccccsecccescesvasssce Rok OS the laws governing the movement of storm centers. ADStract .........ssceccceeee i 99 the position of the planes of certain ne- bulea. Abstract and reference.......0. a0. i 109 report of the committee to collect in- formation relative to the meteor of December 24th, 1873. In full. 2 FIQures....eoee eedesecncassbasbesne res 41 123, 139 the aurora. betract Bec ccivssea saunas sedcctecs iv 21 determining the temperature of the air. Abstract......0+ Saatep acess see iua tas ced sccecesassse wi 24 methods of verifying weather predic- tions. Abstract ........ Bretserieccestaeccess vili 8 Signal Service bibliography of meteor- ology. In full....cceoee frtic Antotees couse eee x TOMALES ON AULOTAS ..cecovee reece eeeeees Stone Mountain patna ane... land and S€a DreeZeS ............cessesees ovens the mean terrestrial ellipsoid, the geoid, and levelling ...... Resehansenneiercnetsasowents whi §=24 MIAROURICALONOATcitstectescdatsusseccncessecsccres ii 93 polarization of light by a narrow slit...dd1 124 Benjamin Peirce.......... monczrarhionereceencheen iv 25 GHOMAINENSOF SOUNG....c.2-cccscers-secseeccoces v 37 deflection Of rivers .............02..ssseeeeeeee vii 23 report as treasurer..v 176, 180, vi xxii, vii xxiv Abbe de l’Epee’s instruction of thedumb..vi 63 Abbe, Prof. E., Apertometer of.................dli 18 Cited ON MICTOSCOPY.........eeeeee Abbey, Westminster S., letter ona ree foun on the Florida coast. Read by C. Abbe. BVGYQUSEN Mel oxecustsatesssacadccceseenesrsnsescrceer ii 202 Abel’s researches in elliptic integrals.....wii 106 _ ACHroMatic ODjeCtiVe......ceccccssccrerersceccreehdd 65 Page. Achromatic objectives, Corrections of....... ili 39 Acoustic investigations by Joseph Henry..4i 344 Acoustics, List of papers on: on phenomena of sound and experiments with tuning forks, J. Henry. Title ONG aaeestinvc tates Uea erento a 22 on sound in relation to fog-signals, from investigations under the direction of the U.S. Light House Board. J. Henry Ti SUL ss ceseuesesvayoutins cocsentedsacceeee Ons AM (45) recent experimental researches in acous- tics, by Prof. A. M. Mayer. J. E. Hil- PAL) “DWE OMe sicssicrcsacsescocesnvceneseeeees i 90 experiments on fog signals during the pastsummer. J. Henry. Title only...t 90 [letter on fog-signals.] J. Tyndall. Com- municated by J. Henry. No abstract...i 91 on audition. J. Henry. Title only......... ii 22 on fog-signals and abnormal conditions of sound. J. Henry. Reference............ di 37 sound in connection with fog signals. J. Henry. Reference........ listeecedcqsaneecendd li 57 acoustic refraction. W. B. Taylor. Ab- BUT GCLsctttesentaneastascevenshavehone erry | leeeiy an account of ropesmtionyt on Bodied! in its application to fog-signals. Annual ad- dress, 1875. J. Henry. Reference......ii 60 exhibition of a telaphon. E. Gray. Ab- SUN ALLaveakssatrecadceagasscuwacninetevake tance inne sete ii 67 [fog-signals.] J. eary, Abstract.........44 85 the telephone. A. G, Bell. Uneaiat aNaven ii 103 commentsonthe telephone. E. B. Elliott. THEME OMA scdaxessascatccaasstacuseces aratevssensaaves di 111 {scientific method and its application to acoustic researches in connection with fog signals.] Annual address, 1877. J. Henry. Jn full........ asehes ebnctedteueccdsseed ii 162 118 Page. Acoustics, List of papers on—Continued. the telephote. E. B. Elliott. Abstract...i& 192 musical intervals. E. B. Elliott. Ab- SEPOCT...000 Mavala ihecsestsNisubsrensesevesessncedened ii 199 binaural audition. A.G. Bell. Abstraet.Adi 68, 69 the spectrophone. A. G. Bell, In full. a upon a modification of Wheatstone’s mi- crophone and its applicability to radio- phonic researches. A.G. Bell. Jn full. recent investigations by the Light House Board on the anomalies of sound from fog-signals. A. B. Johnson. In full. Baap ey Li figuyressevavcstserssavenasacdsuschacncate vi 23 anomalies of sound signals. J.C. Welling. Upiifutllcusavenencsasesdnacteoeacesvaetesse sevens ceeett v 39 the difficulty in determining the direction ofsound. A.B.Johnson. Abstract.-wiii 11, 12 the mechanism of “clicks” and “clucks.” Ay G2» Bell. .Ditle only: ticicestecceseeess vili 18 Action at & GiStaNnCe........cecececsscescccessassssses ~v 156 Adams, Prof. Carl, cited on Malfatti’s prob- lem ...... Dbasbusssnenacsieie eebeewonee sebebnascnentee ii 118 adams, Prof. W. G., cited on electric resist- ANCEvsiasherees shavdeGhabcvsphtssishecroneetesaseabt iv 154 Address of chairman of Mathematical Sec- TION 2.200005 Rusdatemavessines Peschucusenenadeenenerck vi 117 of President Beare VST lisvecesserseacanscceaes iv, 34 Henrys US7TGiecccens-scse se gch Sevaugnsecaadtecnarat ii 60 TOM ys L877 pecvsccstecustasscevasssestpeceveeeecees ii 162 Newcomb, 1879... ..ccceccccoseceeeoee aude cnessaeen did 52 Newcomb, 1880... Woodward, 1881.. Taylor, 1882........ Powell, 1883 ............. Sbskedpeberes WA KRVTI, 10 Welling, 1884... wii xxix, 81 a pA S86 ycesstsweccncrecccstaen eee Wiki x xxiii, 30 IBIS CSGiscssencts ese csseceescnns serene ix xxxv, 46 Harknege: DSSTide. aiicneecsseussesceeneus x xxXvii, 39 of retiring president, Resolution concern- ADs evens Sercesonessos BubavsvcteastadsstwavaxeenueeeT iv 30 on the life and character of Joseph Henry, 44 203, 368, 370 Adhesion and CoheSion............ssessessereeeeneee v 136 Adirondack region, Proposed reservoirs in CBs. cceikevwane spent ecw seetueteccessalaueccersdssnves ii 67, 82 Adjustment of conditioned observations, viii 41 Of tHE CAVED ATs, neq cayentewewewascatssccaesdasnnesra: ii 59 Administration of scientifie work ........... ix xliii Adulteration of food........... Bei avlack dana sehousens iv 39 Aerolite. See Meteor. Agassiz, Louis, Announcement of oath of.i 93 Resolutions on death of....... pavawsuateesenacarnr A 95 Agricola, Georg, cited on mineralogy.........8 77 Ague, Conservative function Of.....ccseeece 5 PHILOSOPHICAL SOCIETY OF WASHINGTON. Air, Contamination Of ccccicsccovsssnessccstseceare iv 37 Alaska, Discoveries in’....... Glaciation in....... Results of envels 3 in.. Value to the United States ofa, iesecsagehneeeaen Alaska-Siberia boundary .......0. cesssseeceeeee iv 123 Albertype process of photo-engraving........l 42 Aleutian Islands, Shell heaps of.............00+ ii 65 Alexander, Stephen, communceation on the zodiacal light. Read by J. E. Hilgard. En: full, 9: fig“ures ics cosssccoeseced ocakeeied 1105, (19) Algebra, Logical Algorithm of the arithmetico-geometric INOS gaanecasbauecacessnaeecsase aspteuprearemraatey vil 102 Alignment curves on any surface............. vi 123 Allard, M. E., cited on the light-house service of the United States................sssssss Alluvial basin of the Mississippi.... Alphabet, PHONG :....stecvaWecectetacccctetansseare ix 35 scientific men and their duties. Presi- dential address. In full......... Ax xxxy, 46 remarks on mosquital inoculation......... vi 10 DiblO Sra ph yn. vesssastacsscescacartatessciees Pe ate $9390 Clove caseeepnccnuakaysessandesusandenany erenassian viii 28 care of pamphlets «.Wiii 29 Charleston earthquake.............sssscseeees ix 42 Bi-metalligmalicscssscancacskeacsess stansyy dii 78, 107, iv 141 Binary arithmetic, Experiments in........ -vi 3, 38 Binaural AUGGION. ...,c0ccncrecsssoncsessserseosacnssdhdee 09 BinOenlar MICLOSCOPES:.c.ccccesecnscesoncscacaenves iv 35 TRIOPOMM ss. saceapescassncescens cocoa svsascsscnecvesvaste eiswenss v 102 Biography, List of papers on: on the life and scientific labors of the late Alexander Dallas Bache. J. Henry. PES OLET CIC C an sosasncca seuss dnonasessanerenecimanacerees i 35 biographical notice of Avebibald Robert- son Marvine. J. W. Powell. Jn full, ii 83, (53) life and character of Joseph Henry. J.C. Welling (27 fult.c:.sssacsssesersecssoeashuee Ad 203 amemoir of Joseph Henry. A sketch of his scientific work. W.B.'Taylor. In PubLUcccrepicare Saectaitnee Sissevbotieaeetarens ii 203, 230 address commemorative of Joseph Henry. PoParkers Cli Sull ccscsessvavessentnccsterse te ik 368 [address commemorative of] Joseph Henry. B. Alvord. In full..............44 370 [remarks commemorative of Jonathan Homer Lane.] J. E. Hilgard. In OPLEUE mses panntatsansesrpeneeseiiieaaeee sreendastaeee iii 1 a biographical sketch of the late Dr. |G. A.] Otis. J. J. Woodward. In full......... iv 171 [eulogy on A. A. Humphreys.] J. C. Well- Ing, -AOSETACE: .cceesccsch cansscrsvecscapasspan vii 4 memorial [to Benjamin Alvord.] M. Baker and E. B. Elliott. In full... epaspelus ane vii 127 126 Page. Biography, List of papers on—Cont’d. relations between Professor Baird and participating societies. G. Mallery. Te JU. sosasacess Petakusncisaescecesee stceeanencsacies x45 Professor Baird as an administrator. W. B. Taylor. In full.........00. praneduadeaacaver’ x 49 Professor Baird in science. W. H. Dall. TUNEL GCsnovcasauetsteepsaseces wovananeastanpcast ere Seas) b the personal characteristics of Professor Baird. J. W. Powell. Jn full............ 2 yi Biological Society, Invitation from....wii 5, wili 4 Biological Society of Washington.............. x 47 Biology, List of papers on. (See also Zoology and Botany :) bacteria and spontaneous generation. J. S. Billings. Abstract........ acsackuae everest 109 principles of morphology. T. Gill. Refer- ONCE. x. SassterencuccctervasheRarvsasoneatbnens aes iv 123 modern philosophical conceptions of life. J. J. Woodward. Presidential address. DTU esecestionnsoncasnest Huea ss aeceeeacoscteen on: v 49 on the organic compounds in their rela- tions to life. L.F. Ward. Title only..w 91 on the building up of organic matter. T. Antiselll.: PORE OMe 22.56, secs -ascevenenscees vi 97 on the possibilities of protoplasm. E. © Coues. Abstract and reference.........6.¥ 102 the three methods of evolution. J. W. Powell. Presidential address. In full. wi xxvii, 110 Abstract. vill organic cells of unknown origin and form found in human feces (two cases). N. germ eultures. J. S. Billings. 30 Li. Bates, Title Only....oc..cccce.sevee-aoene ix 35 on museum specimens illustrating bi- ology. Symposium. Abstract.........AX 35 Black drop... x ...4i 199, wi 23 Black Hills of ‘Dakota: Peowepsedeuseaes parteenesecess iii 125 Blair He We. WD CAbW OT Oe csaersecconeece we Wii 81 PIN GNSSS OOlOT (cacsacscceeeseuncictec cesstes Neaaerns iv 54 Blood corpuscles of man and other animals COMPANOG wresussanscrssussoased selieseeidevesvesneRe 2,4 Blue Ridge, Fault in...... sabe sawanvesces 30 Board of Health, National 37 Boerner, C. G., letter on a shower of the Rocky Mountain grasshoppers. Com- municated by J. Henry. Abstract....... ii 87 BOROslO Crate ecns.cessacencuscresscanen Seeoescnaa vil 34 Bolton, Prof. H. C.,communication on count- ing-out rhymes of children, their an- tiquity, origin, and wide distribution. Reference....... cacy suncechanusanchsenpreeseer ean ese x 13 RON DOVILG, Titie) scc.cccsconeesevcnssverhekscoan i 84, ii 103 Boscovich’s philosophy of matter.....wii xlv, 49 PHILOSOPHICAL SOCIETY OF WASHINGTON. Page Boss’ declination standar@s.........0:..ssecsseee ix 53 Botany, List of papers on. (See also Bi- ology :) on some minute fungi. J.S. Billings. Ab- SEL ACE ca cruespsanvanasyanaste anesnntsaantni Bement i 42 descriptions of new species of fossil plants from Alleghany Co., Virginia; with some remarks on the rock seen along the Chesapeake and Ohio Railroad, near the White Sulphur Springs of Greenbrier County, West Virginia. F. B. Meek. Read by T. Gill. In full. 2 WLQLCS ..sescccene Qeicocaniie ssuctetensdaaaniee 162, ii (26) on the cause and remedy of the potato rot. LL.D. Gale, Ditle O70) ..ccsscsassenscasvaswan i 97 [plants common to Japan and eastern America.] A.Gray. Abstract......... ii 42 the climate of plants. L. D. Gale. Ab- SUP GEE sane the speed of propagation of the Charles- ton earthquake. Reference...,...10....... x 28 remarks on distribution of volcanic ac- ML OTscs oven anebvectuvecusarsivcstspetsccasuceuscetetereets i 102 wind and temperature observations.....ii 18 Fefraction: Of SOUNG..<..csc-veeccascssvoscecenses ii 58 geology of the Colorado region............ ii 76 the earth’s interior..............00 mettsdbercaes ii (77 charcoal in the Crift...........ssccccecessceees iv 122 separation of minerals by density......wi 27 nebular hy pothesis. cack scntsedscssovcerses wi 45 temperature observation...........:c0 see vi 48 outlines of continents 24 SUN! SlOWSsscsesesescesccsveves Wablasvonrsceususeuvy's wii 35 Indian observation of nature...... dendene vil 74 earthquake detonations............0.seee viii 28 Charleston earthquake........... adbcaekee saad ix 42 Dynabraph, (De icccsieecsssetveorses waveastececucrees iii 29 Dynamic hypothesis...............ccccesseseee Peon fie. &.%.< EHHEOTICS OF LOLCOs s2.sicccccesscsscsstsessuvovssvwanct v 126 Eastman, J. R., cited on individual vocabu- JATIOSsecavsocsncscecceetcattnssecasavenceacueerscecse ii (21) communication on a comparison of the thermometers used to determine the correction for atmospheric refraction at the U. S. Naval Observatory. Ab- SETAC ocancscnetansonscvs esi dveaatapmeeeen Saasaupadsnen i 68 154 Page. Eastman, J. R., communication on—Cont’d. the frequency of the occurrence of the zero and the nine digits in the tenths of seconds as obtained from the chro- nographie record of transit observa- MAC SenA ORPRIRCY , ve dccncesossssvscrseeuvaiensacuras i 85 the comparison of rain-gauges at differ- ent elevations. Abstract........ presasesaqel 40) a personal equation instrument. ibe) WON CKGS: CONIBE sa sccccusvancsacaes cxevccteereee sevens 134, 35 Endlich, F. M., communication on mineral systems. In full....... abaeanease anauetere Beater atest electrical phenomena in the Rocky Mountains. Title only....cccscccsscsessessen 95 136 Page. Endlich, F. M., communication on—Cont’d. two bricks from the great wall of China. Title only.....-+ sasetoscsencoonsens maweneseneasecaes i 98 specimens of meteoric iron from Chi- huahua, Mexico, and the structure of meteorites in general. Title only......4 98 the occurrence of pure tellurium in cer- tain gold mines of Colorado. Title ONLY ..reccccccceree dveoceses: ssudunadeneunyos sebaen aaa i 101 the coloring agent of gems. Abstract, li 31 some interesting cases of metamor- phism. Title Only... eeeeeee neenwaaeare iii 27 FEMOV EY ois sevcssccuspossenccesees 5 Conservation and ikstnation OL cSaccesnacsnus a ea Engelman, Dr. G., cited on Quercus......... iv 110 English sparrow question... Entomology. See Zoology. Eotyos, cited on sounds produced by me- . Avesssscebusvenceataness LO WOGOUS sue nscuscnpceussdechesber tassseenencanns SEseeeee di 157 Epicurus cited on philosonky Sonceesras vii xxx Erie, Altitude of Lake........cceeeeeees err ae Erosion as related to displacement............ ii 75 by drifting sand... ........- aceerere renteeascnn: i 57 Errata......... ii p. 4 of cover, iii 148, vi 162, x 114 Errors, Composition of...... Dre vccnaunncaebsersnccesr v 106 respecting the North American Indians..4i 175 BD NGOLY) Olseceacacescsuscetioctnsnsancace niche wi 138, 152 Eruption, Latest, in Northern California, ix 46 Theories of....... Wanasaatise rosasdidesessarvetpcawcccae REO Eskimo shell heaps.......0.-ccccsseesesseeseres eeeees ii 65 Estimation of manganese as pyrophosphate, ii 132 Ether, Hypothesis of an.......... erasaaisehen vi xxix Ethnology. See Anthropology. Eucalyptus on the Roman campagna........ vi 36 Euler ignored by Am. Phil. Soc.......wiii xxxvii Wuler’s theorem. ...cccscccssosessescscccscccesoseceserer XK LOL Eulogy on A. D. Bache... Shera eostees i 35 A. A. Humphreys..... acedsspsocesaadeW By 3h. FLVOlUtOS.....cccescecvccscesessccccneecccece sence covesseess WAR LOT Evolution and phthisis.... sssaccolenesaceveMh, 125 Methods Of.....cs0ssecccseve sscsee connec cdvdscoces WA XX VIL Of the DOW ANd ALLOW... ..eccrscrerececcesseceeee: ix 44 elaments........ suucdspnesendasness poececre tne vii 16 Expansion and beating of ice fields......... ii (22) Experimentation............. dapaspapresecess di 163, wil li Explosion at Flood ROCK. cs..secssessseeeseeees viii 28 ** Explosion” of meteor explained........... -li 143 Exposure of thermometers.........-+.Wi 46, Wii 80 Eye, Optical dofects of........... eArbenssaniaa macneber i 22 Eyes, Apparatus for lesting.......cccccceceeeeddd 53 shining in the dark..,......ccsscccsssrerceereeWhd 13 PHILOSOPHICAL SOCIETY OF WASHINGTON. Page Falconida, Natural r wei Of ....cssse AL Pal LMG ve ssecscunseucee ea cadersaiataes pele Fa: 23 Fallacies AF Se tae: deck. 48 Fallacy as to the theory of gravitation...... v 85 Faraday, cited on Matter..........ccceseescerees vii 48 Farquhar, Edward, cited on personal vocab- TUT Yes. sccnssesteueevanteonvacent PORE ii ii (18) communication on certain remarkable effects of lightning. Read by — Henry. Title only. .cccececeeeeee Feneebopauuend 42 dreams in their relation with aR OBY- ADSEN ACT. :..:c..snssncnecasessnsdvessestte Og TOMALES ON the AULOTLA.......00 sever seceereerees iv 22 FOTNAGOGS ces. dacvecscsosscpebddecuducnscusee een vii 3 thunder storms.......... o sseseaeeduneae sccoses WRAL) TD determining the direction of sound..wili 13 Farquhar, Henry, communication on exper- iments in binary arithmetic. Abstract, v 125, wi3 further experiments in binary arith- metic. hasaésnudespantine v 39 the monochromatic aberration of the human eye in aphakia. Reference, wi 5 flexures of transit instruments. Ab- BUUTCheccccatsespsnesshasbecuntenanen wceeveusessss WOE / 27 146 Page. Harkness, William, communication on—Cont’d. the progress of science as exemplified in the art of weighing and measuring. Presidential address. In full....x xxxvii, 39 a device for viewing the sun by light of any desired wave length. Abstract...x the representation of comet orbits by MOdelS. Reference... sececereescseeee “ete < the constant P in observations of terres- trial MagnetiSM......cecceeeers 13 28 ee se secene scenes x 102 remarks on the black drop.........+ csebabseva ii 199 results from photographs of the transit of Venus..... vital force........ SadRuuEvadsssussoheavsaceseh=s seevaee v 105 temperature observations........ Seceeseevas Wk NYZrOMEtry.....e.eeeee cneevee Rech byauvenssranEnd vi ZIAcCie?S ...... 0000 vision......... PEOPLE problem in probabilities......... Harper’s Ferry, Fault near ......s..ssereeeree avi serene cescs eee 26 36 30 Hart, A. S., cited on Malfatti’s problem..ia 117, 119 Harting, cited on mineral aggregates...... ili Hartley, J., Solution of a geometrical prob- LGYI2) OY sirasccancowasdcnanenevasccaass SakaeEs a veouseREh Hatteras, Geology of Cape...... NonsuetereessersceN& Hausen, C. A., cited on nerve currents...... v 64 28 Hauy, Cited on MineralOgy....ccescerneeeeeeeeed 77, 78 Havana magnetic disturbance and north- Hawaiian geology ...ccccccrseceerseeee paceneunens Pee | Hayden, Everett, communication on the Charleston earthquake. Abstract. AVIOD scasunssseuessues Sitbvsonescaurncsascunvancarennyra ks Hayden, F. V.,cited on base-line methods..4it Hazen, H. A., communication on the retarda- tion of storm centres at elevated sta- tions and high wind as a probable 38 34 cause. In full .......0 ecuaaneemeneuterssene v 108 the coming winter of 188283. Ab- SUPUCE, «cteanansounanese Aton Gnokiceesebscguyeseee v 122 hygrometric observations. Abstract...vi thermometer exposure. Abstract......vi thesun glows. Abstract and reference..wil thermometer exposure. Abstract.....wil thunderstorms of 1884. Abstract......wili the condensing hygrometer and sling psychrometer. s i. 31 the westward movement of the popula- tion of the United States. Reference.i 3 the aurora of February 4th. Abstract...i 47 Hindoo arithmetic. Title only.............- i 53 the recording systems of the trans-At- lantic cables. Title only......s.cccseesseeees bbs the Goldschmidt aneroid barometer. Vo GDSENGCE.......000000 Selaaivancauavaeaceneneeneretncnces i 65 the proceedings of the International Metrological Commission. Title ONLY....000 Mianeaaadanneae Octo oertenseosaenenabc receieros an inquiry into the law of probability. DULG, ORG Sreacvcsstteeyvacsscessoeseseensadteyataen’ i 34 the air thermometer of Prof. Jolly. Title OTe cnvaacmuseunenecarsenace van suscsesa oecasearareenenee i 89 the recent determination of the longi- tude between Paris and Greenwich. Title only .......00.0 Ssecataceacenrsceesanessnaucases i 89 recent experimental researches in acoustics, by Prof. A.M. Mayer. Title OM far ssuseen eertdewccsesasesl witesccsicctnewminatceete i 90 the determination of the personal errors in the observation of astronomical transits. Title only....... eiabbsserssanceuae sek 92 f& new apparatus for the investigation of personal error in astronomical transit Observations. Title o7ly......ssseceeseeees i 106 a proposed reformation of the Gregorian Calendar.) ADStract:.:....ssstscnecscadesce ii 29, 30 the proceedings of the International Metrical Commission. Title only.....di 41 iron facing copper plates. Abstract....ii 42 the measurement of a base-line for the primary triangulation of the United States Coast Survey near Atlanta, Georgia. Abstract and reference........ di 50 standard scales, or measures of length. Abstract....... dazaabeencyenactscedeseteene ee neers ii 136 an optical salinometer. Abstract......... ii 185 Jablokoff’s electric candle. Title ONLY... 00000 ateecne meadadicnaevescetherreuatecsatenG iii 19 phosphorescent clocks. paasasctasuessaucedene ii 111 the conservative influence of disease as illustrated in the phenomena of pul- monary phthisis. 39 Medals, Exhibition Of................06+ mogereoscsese vi 22 Meehan, Thos., cited on the common names of plants........ eabcnscecacesen seston cuadeavenses iv 113 Meek, F. B., communication on new species of fossil plants from Alleghany Co., Virginia; with some remarks on the rock seen along the Chesapeake and Ohio railroad, near the White Sulphur Springs of Greenbrier county, West Virginia. Read by T. Gill. In full. 2 1 62, 44 (26) Death of............ Ryasee coameckansersesces=n bosehebsccdh SLE Meigs, M. C., communication on a map of the head waters of the Yellowstone and Lewis rivers. Wo abstract........ wi 21 the movements caused in large ice-fields by expansion and contraction, as illus- trative of the formation of anticlinal and synclinal axes in geological for- mations. Infull. 4 figures....... ese 33, (22) remarks on glacial period.........csseecerseeedl 37 Members. See List of Members. Membership statistics of scientific socie- LEIS eee cacao eenadavein weeseubssune iesemaecss as vervse x 29 Memoir on the scientific work of Joseph FTGUINV cssasnssnunsnsceassenseee Ruaedapandepasesseucns 4i 203 Memorial to B. AlVOrd ......ssseesssees cesses cosees vii 127 (See also Biography.) Mendenhall, T. C., communication on the measurement of temperature at dis- tant points. Title only.......0.000000..Viik 18 the Charleston earthquake. Abstract, ix 37 remarks on Japanese custom......... Seabnes Mercadier, M., cited on radiophony.......... iv 158 Mercury, Theory Of.....cccccs-cccessseeee-cooveeeeWhdk 941 Transit Of...........0+ oh Meridian, Proposed initial..............seeceeeee vi 106 Meridian transit time determinations...wili 55 Merriam, C. H., communication on the eco- nomic phase of the English sparrow question. Referencé........sseceesseereeeeees x 16 seeneee eens 155 Page. Merrill, G. P., communication on geological museums. Title only........ Exented Goecaetes ix 36 Metaphysic philosophy. MGtAD DIV RIGS Uicvenscdane sadevaesecsanccodssscadeandasc wii xxix Metcalf, Capt. H., cited on theory of target AVA CULCGsgaceresstevanscecsuaueayarsacuessebedaveres vi 145 Meteor, Explanation of explosion of......... ii 143 of December 24, 1873........0++ soeseeh 94, 41 123, 139 (See also Meteors.) Meteoric matter and planetary motions, 11 188, 190 Meteorite, A new........... ehdepuececadanancsveuivees wii 32 Meteorites at Concepcion and San Gregorio, New MeXiIGO.2cossancsipucteciesatunsssveustesace a 24 Meteorological work by Joseph Henry...... ii 236 of the Smithsonian Institution............ ii 295 Meteorology, List of papers on (See also Thermometry) : on the aerial currents observed in fifty balloon ascensions.. S. A. King. Com- municated by C. Abbe. In full........ eo 35 {on aerial currents observed in balloon ascensions.] C. Abbe. Abstract.......1 38 on certain remarkable effects of lightning. E. J. Farquhar. Communicated by Je Henry. Tite OnUY.s.caswsasecedcssencassvons i 42 on the aurora. W.B. Taylor. Abstract... 43 on the aurora of February 4th [1872]. J. E. Hilgard. Abstract.......... Pepsentina React 4 47 on the effects of winds and barometric pressure on the tides of Boston, and on the mean level of the sea. W. Fer- rel. Abstract and reference..........00 Pee wats on the meteorology of Japan. T. Antisell. DULCGs OF efeccanesavcessesoaucessseccsssadonsssoacscess i 70 on the results of astronomical observa- tions at Sherman Station, Wyoming Terr. R. D. Cutts. Abstract and refer- on the laws of condensation of aqueous vapor in the atmosphere. E. Foote. DULUEL OVE Pasecewstsat cucdancusthreueri=tavaicetsececes i 74 on the meteorology of Russia. A. Woeikof. PRET OCEMEG nenacdocustavsecseainetncddcucast ores asenel 00 on atmospheric electricity. (3 papers.) J. RS nryan atte ONY sacs.cesnntsttecsesceecse i 75, 87 on electrical phenomena in the Rocky Mountains. F. M. Endlich. Title only, a 95 on the distribution of temperature over the surface of the globe. W. Hark- MIGSSs , PRES ETENCEseoose socweceesiarcuronestosununen i 96 on some causes that produce rain. E. Foote. Title only...........--- Sonaunenas fewenne i 98 on the laws governing the movement of storm centres. C. Abbe. Abstract... 4 99 156 PHILOSOPHICAL SOCIETY OF WASHINGTON. Page. Meteorology, List of papers on—Cont’d. on the law connecting the velocity and di- rection of the wind with the barometric gradient. W. Ferrel. Abstract.........4 106 on the correlation of the winds and the temperatures of the surface waters of the ocean along the coast of New Hampshire. J. W. Chickering. Ab- BUT ACT. ccccccrscsscesccssccccnescocecconnsssessns scones ii 17 meteorological observations in Peru, and some of the meteorological conditions of that country. A. Woeikof. Title ONLY ..esvscseereeresseeessensecaceens carsesseenesaneens di 35 the glacial theory. J. Henry. Abstract..ii 35 the causes of glacial climate. Symposium. JADSEN ACs act saacsusecsancavaskanesketcesxesaeakn di 43, 45 the comparison of rain-gauges at different elevations. J. R. Eastman. Abstract..ii 49 a new meteorological instrument. J. W. Osborne. ADStracte.....c.scceceecesessesseees ii 63 the hygrometrical condition of the air in high latitudes. E. Bessels. Title only, ii 66 the horary oscillations of the temperature of the atmosphere. G. K. Gilbert. Ab- GUL ACT os sencnnssonnen cssabslsbose-sbecs-remnsndesadenee ii 67 horary oscillations of the atmosphere. G. K. Gilbert. ADStract........ccccceeseeeceeees ii 69 facts relating to the falling of waterspouts in North Carolina, T. L. Clingman. MAD REROCL.esavarskcdavduptdeanetss teas ndaeon ceases’ ii 104 the causes of electrical developments in thunderstorms. E. Foote. Abstract..ii 189 suggestions respecting the study of mete- orology in regard to the causes of yel- low fever. J. W. Osborne. Title only, ili 21, 27 a@ curious manifestation of foree by the wind. J. W. Osborne. Title only....iid 27 air currents on mountain slopes. G. K. Gilbert. ADSstract...........s00sseees PRP erhi | Gest] on the meteorological conditions affect- ing the culture of the sugar beet. W. MeMurtrie. Reference... .....-0 id 142 [the aurora borealis.] C. Abbe. Abstract.iv 21 on the’ conditions determining tempera- ture. W. Ferrel. In full.........0.se00 v 90, 91 on errors of barometric observations pro- duced by wind. G. K. Gilbert. Refer- ENCE... sccceseeree ef fcce ew OL on solar railiation ee pentane Wyoming. W. Ferrel. Title only....... Meatenesosuneare «v 101 on the retardation of storm centres at ele- vated stations, and high wind as a probable cause. H. A. Hazen. In PUL liisinicdvdavssenestiuorseunntsnsectodmesesnetenores Se (LUD Page. Meteorology, List of papers on—Cont’d. [a remarkable halo.] W.B. Taylor. Ab- SEP GEE. scacenscatessnascdeseu 0 svcasoasess BAverin eeW 112 on a graphic table for computation. G. K. Gilbert. ADS¢rGCE...cccscccsssee-consscnnssace ee nkeae on the coming winter of 1882-83. H. A. Hazen. ADStract..:.csccssseccsscscosecsecasssaW Lam the response of terrestrial climate to secu- lar variations in solar radiation. G.K. Gilbert. Abstract......... necandaln eerie. « foul) the thermal belts of North Carolina. J. W. Chickering. Abstract.........0- Perper (geil ( hygrometric observations. H. A. Hazen. Abstract.....c.00 eperesbaappeaetsieareea a=sasgexns aes the Rochester (Minnesota) tornado. J. R. Eastman. Abstract........s-.sces-0e0 ere | as} the sun-glows. H. A. Hazen. Abstract ANd TEfEFeENCe .......0006 ca veopoe suse susucope Rata the relations between northers and mag- netis disturbances at Havana. G. E. Curtis. Reference........ save auaneansaiieed «vii 25 methods of verifying weather predictions. OW Abbe. AUSETACE: scccsccasccassene seoceee Wid 68 thunderstorms of 1884. H.A. Hazen. Ab- SLTACT....0000 pabaveecomnned we :coselaseasennbecieey mE the condensing hygrometer and sling psy- chrometer. H. A. Hazen. Abstract, wili 25 normal barometers. T. Russell. Title OO csactas teres Da yeeeaeeneacniesdeaamaaa Brena baal the sky-glows of 1883. H. A. Hazen. Title OTUG score cstonecopeuncs taasieeyusexy scene Bee the theory of the wind-vane. G. E. Curtis. Reference....... pfeerictae cosceuae ovnsapenwsuasanaseae nine the electrometer as used in observations of atmospheric electricity. C. F. Mar- Vil: Detle O70. ..cscccescsessesvesscaneneneenaee x4 relation between wind velocity and press- ure. H. A. Hazen. Reference........X 10 the Signal Service bibliography of meteor- ology. C. Abbe. Jn full...........+ exnqensa need memorandum on the Signal Service bibli- ography of meteorology and terrestrial magnetism. C. J. Sawyer. Read by C. Abbe. In full........ sgakasdusscuaneeel aati non cou ad Meteors and comets 94 Method of least squares..i 62, 89, vi 150, viii 41 POSOALGD so secccc tadeses «Ai 163, Vi xxxiii, wii li Methods of Cvolution. ..........ccsseccesee serene vi xxvii Modern petrography.....ceccccceceseee ceeee verifying predictions .........0-sesccocccees verifying weather predictions.........vili 8 Metric system.......ccs.ssccccees seeue snaacnpaEnenmeeeae vi 4 advocated by Geodetic Commission....vi 109 for postal purpoSes.........sescrscsecsesssssekl 15, 19 IN MUCTOSCOPY’ cs. ceececccsesedvavaccsedensenataneraanees INDEX TO VOLUMES I-X. Page. VO RICO, GUnIE. Of csecaseusesedssuecottvcassanensaavenesnckWs, OZ Meyer’s atomic VoOlUME CUIVE.......00e0e. WA 15 Mica mines of North Carolina....... CesseseraeWaen 99) Michelson, A. A..communication on the mod- ifications suffered by light in passing throughavery narrowslit. Abstract..iii 119 DICTON A125 c0 “sore ii 16 Progress Of.....csscescoss Savtege ddsuve qiatensuoas deters ii 56 Scientific administrators........ aebahceaatetivy ~Ax xliii OXPCTIMENtAtiON.....cccrrccrseresrreseres fi 163, wil li PHILOSOPHICAL SOCIETY OF WASHINGTON. - Page. Scientific men and their duties............4x xxxv Distribution Of.....ccgie sess .c.-ce20s0ssasseepeeneee nn method.......... sevcccosocee A LOG, Wk XE EI RE and social Progress.........sccseeee soassscaesW "AO societies i vi, viil xxxiii of Washington, and Professor Baird.....m 45 of Washington, Proposed federation of, v 102 of Washington, Statistics of..... 0... x 29 work by state aid.......... doudesycaducoaeeamaaieme vili xli Scrope, G. P., cited on columnar atra peal vili 24 Sea level influenced by winds and haro- MEtTiC PFESSUTEC..-..000-000e e000 vabboaeneseaeee i 53 Seals)Fur-Dearing.,cssssecccsverssenecersrd eosnevienaea Tees bf Secchi, Angelo, cited on elasticity.......... ... v 1380 Saturn’s/ Tings. cxsuscsecetacstensoestee nvens eueiae vi 43 Seconds-pendulum formula Secretaries’ report...wi 111, wii ie “viii xxvii, ix xxix, x xxx Secular change in magnetic declination...i#i 45 perturbations of Polyhymnia by Jupiter, wiii 54 Seebach’s method of determining earth- QUA C LOCI .i0.5 s00esceps pas ly the speed of propagation of the Charleston earthquake. C.E. Dutton and S. New- COMD. BefErenCe.......5s00-coscesesnceorvasuses ie |) 2 Series for determining the ratio of cireum- , ference to diameter......... Porc i 657 Serpent VeNOM...........cceeseeeeee! hips once casenbens wi 38 Sewage in SOils........++ aisyaeuced adv epaga aseaghavensse Sate INDEX TO VOLUMES I-X. Page Sexes, Disparity of, in mollusks............... iii 75 Shade trees and their f0eS.............cceeeeceeees ° aeihy f Shanks, cited on computation of 7.............. i 58 Shasta, Mount........... Srarasantaneene ein tasaenunwsnwarns x Ak0 Shastina, Voleanic sand from................+ 33 Shell heaps of the Aleutian islands.......... 65 Shelters for thermometers........ eiuweaenceseucue vi 46 Sherman, W. T., communication on a visit to Egypt. Wo abstract............100 cesses i 63 travels in Turkey and the Caucasus. No abstract........... eXaeeesbecsecessdauxcpnecusescs ai 65 Sherman, Wyoming, as a site for an astron- (OMICH] "ODSELVALOLY....0-2sabaesenaesesesamed see ii 42 the mortality among army officers. B. AN VOT Cs TeefOnenCercs.tecdcnsneon Sascaven nants ii 49 [proposed governmental insurance.] RB. Alvord NVOGDStr er. swccssscctss cssencsoarss ii 49 [a statistical diagram.] E. B. Elliott. Vo (DUSUL CCE tasscdite sonasanctnspsascaessnaseaneaiwe reais ii 134 animal population of the globe. L. F WES GAGA CE bccnnpsacparones sanasecannacssae iv 27 the relation of scientific method {fo social progress. 8S. Newcomb. Presidentinl MOSES, oLIW PULL cctscce-atncseostseccuasza cases iv 40 the international convention of the teach- ers of the deaf and dumb, at Milan. E. M. Gallaudet. Abstract............... iv 55 mortality statistics of the Tenth Census. J.S. Billings. Abstract............. iv 163, 164 on survivorships, with tables and formulas of construction. E. B. Elliott. Title ONLY ..22000e PCaansereeseassis ceerere maserrero-ce aco ‘v 122 fallacies concerning the deaf, and the in- fluence of such fallacies in preventing the amelioration of their condition. Asi Gre Belly GIGt FUU):; cs sccssessenenccecne comes vi 48 the vital statistics of the Tenth U.S. Cen- sus, J.S. Billings. Reference....... viii 4 a fonetic elfabet. H. Farquhar. Abstract. 1b oa iy the geographical distribution of scientific men and institutions in the United States. G.B.Goode. Reference........X 7 the economic phase of the English spar- row question. C.H. Merriam. Refer- ENCE. .rceccres hab aussnessssdurasihnseess tecesersesccee 16 170 Page. Social Science and Statistics, List of papers on—Cont’d. statistics of the Philosophical Society from its foundation. G. K. Gilbert. Ab- Stract. 00 PisTechantactusscpsess eossuerecthpeaesessseeLeO the progress of science as exemplified in the art of weighing and measuring. W. Harkness. In full.........0+ X XxXvii, 39 association ratios. M. H. Doolittle. Ab- GUVUCUslcascstsvocuenceestace aac Reelaeuannarbnalisievinn x 8&3 association ratios. M. H. Doolittle. Ab- GUITICE. nauavuccsedcustcnciacabassessunrdecanbeann ascents x 94 Societies, American scientific... viii xxxiii ICTON ELGG cc ccssssnccssnacnpevcuiseup aveneveveanecasesekus i vi SUNG PYOLESROL BAIN satsctsaccesssssascnevacessce x 45 SURLISHICS) Of casuscacseclcareestuscrecuses uapauvenabvecess x, 29 OWS ANG SCWALC. avadversnescncsecen secon svcosesssrss iv 38 OMA COLOUG siareccccoscactactsnscusscsceasde 131, 141 116, 121 eclipse, Jan. 11, 1880.........ccc.csccscesescesceses fii 121 Uri 20S TS ce cenesttocssersereee Ad 202, dif 116 heat variations and climate.............s0+ vi 10 parallax derived from transit of Venus, MEthOS.........sesa000s Shasusassateckaacestassetetes v 39 Solid, liquid, and gas defined.............2eee000 v 136 SOMOF ’s THEOTEM........seerccscereccrersscoese Sapecey ix 54 Sondhauss, cited on refraction of sound....4i 57 BOrehi SUA. cts ecerecekcncecncnseasssncscsrevectar iii 140 OU liscenstatravechasacsccbasseasssnsnsedsvassessaccmascnsednsce v 103 Sound, Abnormal phenomena Of......... seers ii 37 and fog man irate ii 57, 60, (45), iw 135, wv 23, 39 DC Aiccsssasevsarsasns Fhoosierenc es neencete Av 143, 183 TUTE eecccnsesveneccunetetens taneuasamtocesececssas faced iv 143 Determination of direction of. li 69, Vili 12 TEOMT CWO SYTOUS: .cccsscescscecccencsnecdsnsese acne Ai 85 Joseph Henry’s researches ON......s00..e0e di 344 Refraction Of...........66 41 57, 167, (48), wv 35, 39, 44 velocity and air temperature.............-00 vi 47 waves and earthquake Waves...........0+ ix 42, 43 (See also Acoustics.) Sounds accompanying and following meteor of December 24, 1873. South! Mountain fhUUtiiessavsasenca-nosxs-cn caensene ECO rececipauncsssesroccacsess ccvessy ates Resisting Medium in..........ccceccseserscsceees Temperature Of.......csscccssee eksahpowananevaeierate ii 73 Space-directed lines......cssecsecseseeseeeeeeeeX 105, 106 Sparrows, 10} ota) ha ee eae aes aah ae ah a x) 16 Specific gravity method.............ccssccseccceee vi 26 SPECULOPNOMO sucess yataadencarccccasavaxcressreas iv 143, 161 Spectrum of Encke's COMEL......ccccessseeecceres i 34 COLON A cr eeacaracencavaneussnencesseecaVarereneseonstst 4i1 117 - Speech, Visible iv 55, vi 60 Speed of propagation of the Charleston earthquake...........+ neent oneonesany Monadaeeess Vl 15/20 PHILOSOPHICAL SOCIETY OF WASHINGTON. Page Spencer, Herbert, cited on ceremonies....4x 20 growth Of crystals.d.........00sscccssseses vaaset ON MIOTION sschesmsssceued semandoanesnauatee NLOTVE CUITEDES, cioccersdcccces ecccpecnscnacusunseus vi 62 THO WIG: sc vear csaseacasaeexs a aacapots «ee W 164, 166 Spheres, Problem concerning capussnas LOT Spheroid, Distances on any............. Spied Spofford, A. R., communication on proposed reforms in spelling the English lan- Title only... ossus sunaadenceNeunncee ii 42 .-Al 109,» 64, 103 score) (22 guage. Spontaneous generation......... Standard for MicrOMEtry......ccccseceeeees Standard time.......scccssesssenssnccess adopted by the society .............. seaman A system of......... Seasasteeeaerere panana Standards of declination...........ccceeee LENS UH iseseneasspoescecs speesecechack psopenssneetneeee Lee VEAL Oi vucenvctucarccouss cedseasdonwace Rercsitecto ili 78, 107 Standing rules of the General Committee, a xvii, if vi, iit vi, 149, iv 11, v 11, vi xii, wii xii, viii xii, ix xii, x xii Standing rules of the Mathematical Section, vi 115, vii 85, vili 35, ix 51,x 81 Standing rules of the Society..4 xvi, if iv, iff iv, 149, iw 7, 30, 38, v 7, vi ix, vil ix, viii ix, ix ix, x ix Star catalogue Sere at U. S. Naval Ob- SOLVALOLY: sc ccscctasss| ce acvecsoncsseaeduessutennnnnt i 74 New..... mateeren aves vaeensave teas yesetpenaeneal ix 14 Stars, Aenean Of ccccssee-sussacevuuspseecsrnanh Am mmrny TMB LES “OL. a cecseonssnssn crnecnetcnet serene veAX 15 Station Crrors....0..seeeee ison Nenany ane esnoscce eekh 82 Statistics. (See Social Science.) Steam as a disinfectant........eceeeee ccc cscassuekRn Oe Steiner, Prof. J., cited on Malfatti’s problem, fi (115 on Feuerbach’s Circle....,....0+++++ sseeeee Wild 46 Stellar photometry.......... agree oqueccce\ssnanseee wane Steno, cited on crystallography................+. 2 ey i Sternberg, Dr. G. M., Researches on Bacillus TUSIATIES seasncccnnseconccenecss ssoasevaeeenae sisause iv 39 Stokes, Professor, cited on refraction of AOUNGs: sseccssncccssns nena desopenennee 41 58, (47), v 40 Stone, Ormond, communication on the de- termination of the errors of a pro- visory catalogue of fundamental stars. TUGLE: OFU1Y aves sessntenenaseusdonsvaunden cane aeeakRtd i 62 the correction of a comet’s orbit. Refer- OTIC .onceannscacéeanedeavasexsleeesaetenneeaaeaeenm Ah 22 a problem in probabilities. Abstract....x 89 the orbit of Hyperion. Abstract and ref- CLENCE, s.gaccocesnesreceseses an scisuookecaseneey asebece x 104 Stoneham, Me., Topaz from.........sececseeeee wili 5 Stoney, cited on the radiometer... ii 81 Storage of electric CNETYY.....MWerereeeeerereeeW 46 Storm centres, Movement of....... ecavagkesaachsnee meet INDEX TO VOLUMES I-X. Page. Storm centres, Retardation of........ ev 108 BSPOLINS ANGAUTOTAS...vccosseceseccseclhucvcesertse csehes a 45 EUW OL vaste Atavus pesakhatencdntuassvecesveucossuncazesces Thunder Storr, Dr. G. C. C., cited on the classification of mammals....... Bosnecartet ap seube cet eeacaathed fi (3) Strata exposed in shaft of water-works ex- HOUIBION sbseticteccsscs ceearedecanteoearstase cect vii 69 Struve, Otto, cited on determination of planet’s mass from observations on RPLDCNI UGGS se ecetcrassscvecses- cer ucaess cesses eterst wi 132 Satellites) of Uranus. ...c....esccsesscocscecescnses SARC OSsantcnsseacaccssnanensvuvaccss wi 133 WL NITCSIMAL SI cs cescdassvervosscasusuenevwsvabssa wi 135 BUN! SLOWS siasctusantouccctecs vebench acevateaveenys vii 35 topoOphone.......ssecseeeeee whsdutusspsseenatceees viii 13 resolutions on the death of G.C. Schaeffer, i 90 Telephone, Exhibition Of...............sses00 ii 67, 103 COMMENES ON Neintsscssdonccsanasnacyueceseasesveees ii 111 Telephonic study of binaural audition......ii% 69 PelopHotescisc!dasvecscdsesacercubsnatecestae'steeys . ki 192 Telescope for Naval Observatory.............. i 62, 63 Wiz PHILOSOPHICAL SOCIETY OF WASHINGTON. Page. Temperature and pressure, Diurnal changes OF, coxecsaowetetaunat wanna? Mebbasbawtdaadaqacsh se cses ii 67, 69 Conditions determining.. .........+ ecucseanse v 91 distribution over the surface of the globe, i 96 Measurement of atmospheric................Wi 46 of sea water as related to winds on the coast of New Hampshire........ aescaatnea ii 17 75 73 the air........ Sikes chennthnnneeionchaanneecaacnne seeWh 24 the human body......... sesso of pores fee ef (See also Meteorology and Thermometry.) Temperatures at which differences between mercurial and air thermometers are ZLEATESE ....ccccrceccncceves soccccscecrossceveeseses ix 25 OL the Pacific OCEAN... ccccssvcsoeessceccevesousssh ii 192 Tenth census mortality statistics.............0w 164 PROTA OG MAVAIS..ccascesgcconsssscocdnkpesseanscecnssetses v 98 Terrestrial magnetism, Bibliography of..x 23, 27 Constant P in observations of............... x 102 Terquem, cited on Feuerbach’s circle...wili 46 TDexns Cross "TIM DETS:,ccssssanecadessencssnccssuer ene <6 Thanhoffer, cited on the pulse............. 0000 vi %7 Theatres, Burning oOf......... namevnaed oeaneeeeeeaenes di 95 WHGOIGLY, sacvscsvasnedasch wadaavepseees ae “pas v 103 of the American Indians........ auaceacsasanecee Lio PRL OO) OLICTYONA. scsdecascucusdsecocucdecnsaccrssescse wi 152 practically tested by RE er ae eR vi 138 Thermal belts of North Carolina..... ....... vi 11 Thermometry, List of papers on: on thermometers. B. F. Craig. Title OTL cavacacuasnsavecasarcehesnpenatana esa savcamawoeners i 42 a method of verifying with exactness the indications of a thermometer. B. F. Craig. Tetle On t....00....0000eceesreesee scevee i 43 a@ comparison of the thermometers used to determine the correction for atmos- pheric refraction at the U. S. Naval Observatory. J. R. Eastman. Ab- BUT ECU senpssncuneasdaannescsaans Geaubeseadsaeneteustssnd i 68 on the air thermometer of Prof. Jolly. J. Bi. Hilgard. Title Onis. sacceesesosessasecess i 89 determining the temperature of the air. iG: Abbe: | ADSiraCis.cccteaetsoecectecneceseae vi 24 hygrometric observations. H. A. Hazen. BAL DAUCEC iauvenmaneneieaneensnsnpsnuasrseensstbaNe set: vi 36 thermometerexposure. H.A. Hazen. Ab- GUNACLcatonesecundatastoxssnaesesadessapeecetssnesenee vi 46 thermometerexposure. H.A. Hazen. Ab- SUPACT...c000 Sibusysade son upstneesannese Deneenn «Whi 80 the measurement of temperature at dis- tant points. T.C. Mendenhall. Title ONLY... 000 So rercestnceec nrerenrtee rater viii 18 the condensing hygrometer and sling psy- chrometer. H. A. Hazen. Abstract..wiii 25 Page, Thermometry, List of papers on—Cont’d. temperatures at which differences between mercurial and air thermometers are greatest. T. Russell. Jn full. 1 fig- MUTE ios avuscoesvancccdenadéuecoscogutasseonnesaaheineeal ix 25 the gilding of thermometer bulbs. J. H. Kidder. Title only ....scccccooscresssooan kX 33 effects of solar radiation upon thermome- ter bulbs having different metallic coverings. H.A.Hazen. Abstract..ix 33 Thompson, Gilbert, communication on the physical-geographical divisions of the southeastern portion of the United States and their corresponding topo- graphical types. ADstract.......006 s+ ix _ 22 What is topography? Abstract remarks On glacicLS.......ssee-seceesceee —_ Indian paintings, io....ccccccscssvancsss sscnen vili 16 | Thompson, Prof.S. P., cited on plecteinieg .v 168 Thomson, Sir William, cited on rigidity of LHC) GATE ti sencctenscesvivey actesesastsopeteaeaenee ii 78 Sumner’s method a wxvoverRy OU; Volt-meter Of....ccccescccdsscccesencreesvencetvane viii 26 Thomson, William, communication on a new method for detecting and measur- ing the optical defects of the eye. RREPETENCE.c...00-eaccccoeseasew éavoucasonaneas aaa” i 22 Three methods of evolution.........00.000 «vi xxvii © Throwing-sticks....... «ix, (18 Thunderstorms in 1884 wil 10 Electrical phenomena of....... sscueeneseaeaeeea ii 189 Tidal retardation and consequent crumpling, viii 19 Tides at Boston influenced by winds and barometric PreSSuUre,........sseccsccsossesennes Tillo, Col.,-cited on levellings in Asia........ Time, A system of standard.........c..-sseceseeeee determination with a meridian transit..wili 55 w Ati 26, 40, x 104 Todd, D. P., communication on solar paral- lax from the velocity of light. Refer- OMUAE thviuhtsxecveusnus Seep ritcccer ee woyeceseanee iii 74 a mechanical attachment for equatorial mountings to facilitate sweeping in right ascension. Abstract and refer- ENCE ...s0000 chen ane sve denen envakseneseassueheaemauee .Aid 142 the solar parallax as derived from the American photographs of the transit of Venus 1874, December 8-9. Abstract GN TEFETENCE. .veccvseccesonaerars ecscseesconceveel WY 168 Todd, J. E., communication onsquaternary deposits of western Iowa and eastern Nebraska. AdStract. .ccosrccsscresscesssenek © 120 ...4 137, 202, wi 106 INDEX TO VOLUMES I-X. Page. Todd, J. E., remarks on charcoal in the drift...... Manqantenarenelcasaeu tena aseecece aeneanas fv 122 Toner, J. M, communication on a method of describing aud locating with ease the approximate positions of geo- graphical regions. Title only........ sooeek 97 the burning of theatresand public halls. PEPOPEM CILGn seessentercssuces are Srecvewecestescxall GO amalformed dog. Wo abstract............ 41185 earth vibrations at Niagara Falls. Ab- RAM a TG ietue ten ab eecstshinsaasnancncssnawdneneeceauae iv 186 coins and medals. Abséract......... scrcnane Wi 2 remarks on care of pamphlets............ viii 29 Tonto Sandstone, Age Of ............c00 ducedsaseuuee i 109 Topaz from Stoneham, Me..... we With 5 Topographic map defined.............. eck) Tt types in the southeastern States......... ix 22 Topography and geology of the Cross Tim- bers of Texas......... eohaeheusel sasaurunes assess > ANA StTUCTULC......000 ceeeee Subsosnene Sense enatuks > ae COANE. serccsseiscessss Baaeakasest! Saseseanthnenaancsse x 14 Topophone.............. avdcaves maseonidanc samedects we Whit 12 Tornado at Rochester, Minn..........0..ses00eWiil Torreya in Southern States and Japan......id 42 Townley, &., cited on transmission of sound, : wv 42 PUPATIS TG LO XELLOS casi scessonsqcosaececacesasse eokeeasgWAlh, (27 Meridian........ CeAerECEELS Reativeeescastuesves verse will 55 of Mercury....... eeaGhinanesucqsidesvcactovessecerceve ii 199 Mercury, May, 1878..... lid 43 WenS) 1874, .0. ot tecccsscvecens i 63, ii 31, 33, iw 168 MS ites arccavcesarxccelescsarcactersuossncnce vi 21 Trap of Orange Mt., N. J........ Rebs sa seseuative -viii 24 Treasurer’s report.....v 176, 180, vi xii, vii xxiv, viii xxviii, ix xxx, x xxxiv Tremors detected by astronomical observa- TIGIS ssn ccesassee peteepenaae toxin snasanscnack basses iii 120 Triangle, Formule for the area of.........wiil 37 Problem concerning...........0+ Biaecteecerspre Rhy 700 Trisection Of angles...........sscecceseesseeseses sesame 90 Trouvelot, L., Drawings of nebule by........ pt eal Tucker, R., Solution of a geometrical prob- PGNEM UD Vraesctsuastenndvucentuaxacevscsnccestesneses iil 65 Tupman, —, letter on solar eclipse. Com- municated by W. Harkness. No ab- Sill Cbreccssecrodseccnatessne Rearenusetsegucdassossacad A 56 winin es |W. diy DAL) Ofsic..cceasresseedeoveesecee's v 102 Tyndall, John, cited on photophonie experi- MENIS...inoces reecceo Sassebalehadtatas ass pedenen iv 152 sound anomalies.......... dechcadesaceceoaccess -v 33, 41 heat absorption by the air..............6 -v 94, 96 Introduction of........ snore toneenn thc ret eer i 65 letter on fog signals. Communicated by ereLenTy. TINO GOSE CCL. .2.-.ccccscesesacseesse i 91 Uinta Mountains, Permian rocks of.........44 106 Uniforniitarianianisss.i.sscsaveteactetecccccccecWiil 6 United States, Centre of population of....... s£) 35 Geographic centre Of............se000 acacecseee i 22 Wrara.:.. a by Page. Waves, molecules and at@ms.........ccceseeseeeees i 66 Weather forecasts......ccsscsssseesescceses ‘v 122, vidi 8 Webb, Capt., cited on phenomena of sound, ii (49), (50) Weiss, Prof., cited on mineralogy............4 78, 79 Welling, J. C., communication on the life and character of Joseph Henry. In fll sasaavaveessadtsoueen acus lat iscnaestesenie otouanepem ii 203 anomalies of sound signals. Jn full.....w 39 the atomic philosophy, physical and metaphysical. Presidential address. Tv full cvercsess Aroorrrtrecort: etoues vii xxix, 81 eulogy on Gen. A. A. Humphreys. Ab- SUPACE cvccassun scdvev veces evauvasesdecudcuves tanner vii 4 remarks On vocabularies. ..........ssscee coos fi 28. Grifting DUOVS..,.ccccevss,sseveesancsssnadeeenen wii 15 Indian observation of nature............. vil 75 Wells, D. A., cited on medium of exchange, hii 101 Wenham, cited on microscope apertures..iii 19 Werner, cited on Mineralogy..........c00 cree i78, 79 Wernich, cited on contamination of air by SOWALO iccacsecaasahev des kaandonawuerati eva ndecane iv 38 Whatiis'a glacier ?t:.2i.c22 Saesseswerncueutensemeat wii 37 Wheatstone’s microphone, Modification of, iv 183 Whewell, Dr. W., cited on attraction..........W 161 Greek philosophy.............0000+ see Whi XXXxVili White, C. A., cited on the loess of Iowa.....iw 121 communication on the evolutional history of the North American Unionidee. Title only...... sodscechsdeadseaasseddtvnaseuceenete ii 181 asymmetry in the form of the human cranium, (Z2tle Onlys..ccacovsscetoners ae ii 190 the fresh-water shell-heaps of the in- terior rivers of North America. Title the subject of the Permian formation in North America. Abstract...........0+ .-did 104 artesian wells on the Great Plains. Ref- CV CUCE a cascacesaencennsessnpawe osececcuncawupausepenes v 101 remarks on the relations of plants to LCOLOLY.....ecseeeeeee dvsesee)ischeust one usesaneash iv 119 loess of the Mississippi valley........... «iv 122 VETOED. ....00..eccee0 enaaie sabe horanedyarsl annie debsecansWp 09) theory of permanence of oceans......... vi 93 drainage system of Iowa........4 oo -decuassewenn oO) White, Prof. I. C., Discovery of Permian fos- sils by........ anacdtecasconeeeee doveocoeveusnastuna ey LOG Whitfield, R. P., Observations on Limnea Diyas sch esectuck bunetes wacutdaleeten ea ants Whitney, Prof, Je Di; cited | on geology of Great Basin.......... edaauedeaenohe doceususssstoneaena Whitney, Prof. W. D., cited on™individual vocabularies....... ined chuaucaneeecasadadaeyeents ii (19) Wiebe, H. F., cited on thermometry......:..4x 26 INDEX TO VOLUMES I-xX. Page. Wild, Prof., cited on thermometry............ ix 33 Williams, G. H., communication on the methods of modern petrography. Ab- BUNCE erspecdesvsscesn=-salaceub> sbraseanesve Stes vii 36 Willis, Bailey, communication on the topog- raphy and structure in the Bays Mountains, Tennessee. Reference....K 7 development of a perspective map from acontour map. Title only..........0.0000 Part!) Mount Rainier and its glaciers. Ab- BUNGE ssusccescess Reatenaeanedtate cadacencancventrestex x 10 remarks on geology of Cascade Mount- HET Gee esr ee Bee eCCRRE ET Serer esnenstracne eeeatee ix 8 Winchell, Alexander, communication on the progressive dispersion of mankind over the surface of the earth. Title ONLY... 2.008 pasmeenasahan cas shakes fackussaceatdsecesten Ail 32 Wind and hygrometry....... AAT, vi 36 TFUERW OVI UEACLION ..5cnsccccseboctascscuscesceneaasne iii 31 retardation of storm centres..............+. v 108 as related to barometric gradient............ i 106 velocity ANd PLreSSULe.....seccceccesesecersees epee Ay Winds and barometric pressure-in relation to tides....... auuansayacnnasccserecdeeeaaeun Be eercss 4 53 as related to ocean temperatures on the coast of New Hampshire........... 17 observed in balloon ascensions 35 ONGMOUNERIN SIOPCS;. 7 re ¥ i » ' ‘ A ‘ores i is a 4 , 4 ‘ i ele pa 4 ; oe { Ne ) p ‘ : ais y ay : seat bat ‘ ‘a3 \ ( P f i Cs Apna va ’ : 4 es ss has FD ‘ Lh thee : i 4 f Ay Te < he ab eh t 7 t : : ’ re te y t ‘ ) * Y , . pete) Ate aS Ar eth Neri . hd ‘ * Naty ed ies i ‘ y , ar P =a : al a ¥ ’ v < 3 ve ? ; ° x : f Se ee . “+ f ine a ‘ Wee I i \ ; ; ‘ 4 s ’ ‘ a+ tar BO Rate — aa ees” ‘eaer DARARARA AN RAP aif : | ny waa > TT ee an nanRannnan nan a aaa saad es aa Psst AAA aye TITRAANY p Pig! vw Naan ARAN AYANAIA RannArnn i we AANA aAAnnd: t . rconas AnAAAA OAR ARRAN AannnnnaNnnaaanAs ananannanes NAR Ate 2 nah a AAA anaanraann A ~ SS NAAT i AAAAA AAAAR Aap AANA ‘na Snndat ga AAA AMA. 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