EERE Pep ech en tee Genie te ru pans Pie : Saar Nae: ane? Sede it = atone Sa ires pre tis ar coe a ite, eS vss em Sim Vs Nw 7 t 7 Pid a Ai ch Ph! ot hy: 4, Mish’ U2 aioe Sua - : n ' . i r | Arty an \ a3 Ma ‘ ee eye we | i‘ j hay ie r A .\e o hs ts 5 # il abd ’ va] if) ‘ ! t ; i” i] ee ri ug j t ‘ 4 : . * 4 yw Aa F 4 ry i ee M's} : ay rhe " ' ay) ” “ vane th Cait ln at \ f if TE ht ‘ih : | Ue WM iid \ ne BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE x & a “S CO Sse SS my REPORT OF THE ANNUAL MEETING, 1938 (108rH YEAR) CAMBRIDGE AUGUST 17-24 LONDON OFFICE OF THE BRITISH ASSOCIATION BURLINGTON HOUSE, LONDON, W.1 1938 iii CONTENTS. PAGE OEEICERS AND COUNCIL, 1938-30). wi. Stee ee eee ete eee cee Vv SECTIONAL OFFICERS, CAMBRIDGE MEETING, 1938 .............-+- Vili ANNUAL MEETINGS: PLACES AND DATES, PRESIDENTS, ATTENDANCES, RECEIPTS, SUMS PAID ON ACCOUNT OF GRANTS FOR SCIENTIFIC RURP OSES (OST — LOGS) ee aie: as ocs oerereranh ere seyshore agi a ereretelene wiesvede x NARRATIVE OF THE CAMBRIDGE MEETING ..........-.00ee eee eees Xiv REPORT OF THE COUNCIL TO THE GENERAL COMMITTEE (1937-38) .. Xvi GENERAL 'TREASURER’S REPORT AND ACCOUNT (1937-38).......-.- XXXVili RESEARCH COMMITTEES (1937-38) ........--- irotoacleye sala ce Maree aie hii RESOLUTIONS AND RECOMMENDATIONS (CAMBRIDGE MEETING) ..... Iviti THE PRESIDENTIAL ADDRESS : I. Vision in Nature and Vision aided by Science. II. Science and Warfare. By the Rt. Hon. Lord Ray eicuH, Sc.D., IPAUCID PARE RRO cyte cm wh ener saree ties eee oere tole « cheue: dreeeminalaeie I SECTIONAL PRESIDENTS’ ADDRESSES : Logic and Probability in Physics. By Dr. C.G. Darwin, F.R.S. 21 Recent Investigations in the Chemistry of Gold. By Prof. C.S. GIBSON NOUBA GbR a. bac otis cette e Meera te alot Onis iain cher 35 Development and Evolution. By Prof. H. H. SwINNERTON.... 57 Oceanography and the Fluctuations in the Abundance of Marine Animals. By Dr. STANLEY Kemp, F.R.S. ............... 85 Correlations and Culture. By Prof. GrirFITH TAYLOR........ 103 Scope and Method of Economics. By R. F. Harrop ........ 139 The Changing Outlook of Engineering Science. By Prof. R. V. SS OMMUEM WY BIT SUE SER 5 ca aie’ car eyavsep ener e btthes «aie chlsntutes iaemans a 163 The Orient and Europe. By Prof. V. G. CHILDE ............ 181 Eye and Brain as Factors in Visual Perception. By Dr. R. H. PIBETOUIEESS eet ceres tances es oers elo trove Gk aac ie Gi a Pe elle a connate 197 The General Physiology of the Plant Cell and its Importance in Pure and Applied Botany. By Prof. W. StiLes, F.R.S. ... 213 The Function of Administration in Public Education. By PSVRIRGEINT: cis ciounicle «i atsie giercial ove/'eiuere aioe Giaeenen ase tietcbaas Shak 235 Ley-Farming and a long-term Agricultural Policy. By Prof. RAGS OTAPLEDONS C2B. Es co cccciels satis cis « sere sean wens 245 iv CONTENTS PAGE REPORTS ON THE STATE OF SCIENCE ............---5 airditat'y Sheree 263 SECTIONAL TRANSACTIONS .....--.eeeeeeeeeeees Bic | ones KOT CONFERENCE OF DELEGATES OF CORRESPONDING SOCIETIES ......-.. 523 EVENING DISCOURSES ........--.. HES Pde ot ae es RR EENOI IIA hos 0G ic 535 REFERENCES TO PUBLICATION OF COMMUNICATIONS TO THE SECTIONS 537 ALEXANDER PEDLER LecTuRE. By Prof. H. L. Hawkins, F.R.S... 546 Norman Lockyer Lecture. By Dr. H. SpENcEeR JoNsES, F.R.S. .. 557 APPENDIX. A ScIeNnTIFIC SURVEY OF CAMBRIDGE AND DISTRICT ....... AAS I MERIDIEN dee char ese yeusl sicvencve si SEUNG hr DAR tuere ete saehetie day 6 at Otte eae 2ou PUBLICATIONS OF THE BRITISH ASSOCIATION .............2.++25- At end EE EE BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. OFFICERS & COUNCIL, 1938-39. PATRON: HIS MAJESTY THE KING. PRESIDENT, 1938 : Rr. Hon. Lorp Ray teicH, D.Sc., LL.D., F.R.S. PRESIDENT, 1939: Str ALBERT SEWARD, F.R.S., Sc.D., LL.D. VICE-PRESIDENTS FOR THE CAMBRIDGE MEETING. The CHANCELLOR OF THE UNIVERSITY (Rt. Hon. the Eart BALDWIN OF | BEWDLEY, P.C., F.R.S.). The VicE-CHANCELLOR OF THE UNIVER- | sity (Professor H. R. Dean, M.D., | Master of Trinity Hall). The Lorp-LIEUTENANT OF CAMBRIDGE- SHIRE (C. R. W. ADEANE, C.B., aR). The HicH SHERIFF FOR CAMBRIDGE- SHIRE AND HUNTINGDONSHIRE PEAKE, J.P.). THE Mayor OF CAMBRIDGE (E. SAVILLE Peck, M.A.). Alderman W. L. Briacs, J.P. | The CHAIRMAN OF THE CAMBRIDGE- (T. | SHIRE County Councit (Councillor A. R. ForpuHam, J.P.). The Rt. Rev. the Lorp BisHoPp oF ELy (Rt. Rev. B. O. F. HEywoop, D.D.). The Rt. Hon. Lord FarrHAvEN, D.L. Alderman H, FRANKLIN. W. A. H. Harpine, M.A. W. W. PEMBERTON, M.B., B.Ch., J.P. Sir J. J. THomson, O.M., F.R.S. Prof. Sir F. GoWLAND Hopkins, O.M., F.R.S. Sir ALBERT SEWARD, F.R.S. | The Very Rey. the DEAN oF ELy (Very Rev. LionEL E. BLACKBURNE, M.A.). Rev. Prof. C. E. Raven, D.D. VICE-PRESIDENTS ELECT FOR THE DUNDEE MEETING. (To be appointed.) Vi OFFICERS AND COUNCIL GENERAL TREASURER. Prof. P. G. H. BoswE Lt, O.B.E., D.Sc., F.R.S. GENERAL SECRETARIES. Prof. F. T. Brooxs, M.A., F.R.S. | Prof. ALLAN FerGuson, D.Sc. SECRETARY. O. J. R. Howartn, O.B.E., Ph.D. ASSISTANT SECRETARY. D. N. Lowe, M.A., B.Sc. ORDINARY MEMBERS OF THE COUNCIL. R. W. Aten, C.B.E. Dr. F. W. Aston, F.R.S. Prof. F. AVELING. Prof. F. BALFOUR-BROWNE. Sir T. Hupson BEARE. Rt. Hon. Viscount BLEDISLOE, P.C., G.C.M.G., G.B.E. Dr. W. T. Carman, C.B., F.R.S. Prof. F. DEBENHAM, O.B.E. Wren Gankxen EVAN Prof. W. G. FEARNSIDES, F.R.S. Prof. H. J. FLEuRE, F.R.S. Prof. F. E. Fritscu, F.R.S. Sir RicHARD GREGORY, F.R.S. Prof. A. V. Hitt, O.B.E., Sec.R.S. Prof. T. G. HI. Prof. T. S. Moore. Prof. J. C. Puiir, O.B.E., F.RS. Prof. J. G. SMITH. Lt.-Col. W. CAMPBELL SMITH. Prof. C. SPEARMAN, F.R.S. Dr. C. TIERNEY. Dr. J. A. VENN. Prof. Sir GILBERTWALKER,C.S.I.,F.R.S. R. S. WHIPPLE. J. S. WILson. EX-OFFICIO MEMBERS OF THE COUNCIL. Past Presidents of the Association, the President for the year, the President and Vice-Presidents for the ensuing Annual Meeting, past and present General Treasurers and General Secretaries, and the Local Treasurers and Local Secretaries for the Annual Meetings immediately past and ensuing. PAST PRESIDENTS OF THE ASSOCIATION. Sir J. J. THomson, O.M., F.R.S. (1909). Sir OLIVER LoD3E, F.R.S. (1913). Sir ARTHUR Evans, F.R.S. (1916-18). Prof. Sir C. S. SHERRINGTON, O.M., G.B.E., F.R.S. (1922). H.R.H. The PrRiNcE oF WALES, K.G., D.C.L., F.R.S. (1926). Prof. Sir ARTHUR KEITH, F.R.S. (1927). Prof. Sir Wit~t1am H. Brace, O.M., K.B.E., Pres.R.S. (1928). Sir THomas H. Horranp, K.C.I.E., K.C.S.I., F.R.S. (1929). Prof. F. O.. Bower, F.R.S. (1930). Gen. The Rt. Hon. J. C. Smuts, P.C., C.H.,-F.R:S. (1931). Sir F. GowLanpb Hopkins, O.M., F.R.S. (1933). Sir JamEs H. Jrans, F.R.S. (1934). Prof. W. W. Watts, LEZD3 Sc.D: F.R.S. (1935). : Rt. Hon. Lord Stamp, G.C.B., G.B.E., D.Sc. (1936). Prof. Sir EpwarD PouLtTon, F.R.S. (1937). PAST GENERAL OFFICERS OF THE ASSOCIATION. Prof. J. L. Myrss, O.B.E., F.B.A. Prof. EF. Jj. M:; Stratton, D.S:0., O.B.E., M.A. Sir FRANK SMITH, K.C.B., C.B.E., Sec.R.S. OFFICERS AND COUNCIL Vii HON. AUDITORS. Dr. Ezer GRIFFITHS, F.R.S. | R. S. WHIPPLE. HON. CURATOR OF DOWN HOUSE. Sir BucKstoN Browne, F.R.C.S. LOCAL OFFICERS FOR THE CAMBRIDGE MEETING. LOCAL HON. SECRETARIES. C. H. Kemp, Town Clerk of Cambridge. A. Tasrum, O.B.E., M.A., LL.M., Clerk to the Cambridgeshire County Council. F. P. Wuite, M.A., St. John’s College, Cambridge. E. N. Wittmer, M.A., Physiological Laboratory, Cambridge. LOCAL HON. TREASURERS. R. Epx, M.A., School of Agriculture, Cambridge. R. H. Parker, M.A., D.L., M.C., Barclays Bank, Cambridge. LOCAL OFFICERS FOR THE DUNDEE MEETING. (AUGUST 30 TO SEPTEMBER 6, 1939.) CHAIRMAN OF THE LOCAL GENERAL COMMITTEE. THE Lorp Provost OF DUNDEE Joun Puin, LL.D. LOCAL HON. SECRETARIES. W. A. R. ALLarpicE, Lord Provost’s Secretary, Dundee. Prof. E. T. Copson, University College, Dundee. Davip Latto, Town Clerk, Dundee. LOCAL HON. TREASURERS. Wo. AITKEN, City Chamberlain, Dundee. Quintin B. Grant, Royal Bank of Scotland, Dundee. viii OFFICERS OF SECTIONS, 1938 SECTIONAL OFFICERS. A.—_MATHEMATICAL AND PHYSICAL SCIENCES. President.—Dr. C. G. Darwin, F.R.S. Vice-Presidents—Prof. W. L. Brace, O.B.E., F.R.S., Sir ARTHUR EDDINGTON, O.M., F.R.S., Prof. R. H. Fowrer, O.B.E., F.R.S., Dr. G. W. C. Kaye, O.B.E., Prof. F. J. M. Stratton, O.B.E. Recovdey.—Dr. EzER GRIFFITHS, F.R.S. Secretavies.—]. H. AWBERY, Prof. W. H. McCrea, Dr. D. M. WrincH. Local Secretaries —Dr. N. FEATHER, Dr. J. WISHART. B.—CHEMISTRY. President.—Prof. C. S. GiBson, O.B.E., F.R.S. Vice-Presidents—Sir F. GowLanpD Hopkins, O.M., F.R.S., Dr. W. H. MILts, F.R.S., Sir Wm. Pops, K.B.E., F.R.S., Dr. F. L. Pyman, F.R.S., Prof. E. K. RIDEAL, M.B.E., F.R.S. Recorder.—Prof. J. E. Coates. Secretaries —Dr. H. J. T. ELL1INGHAM, T. W. J. TAYLOR. Local Secretary.—Dr. A. E. MOELWyN-HUGHEs. C.—GEOLOGY. Pyresident.—Prof. H. H. SwINNERTON. Vice-Presidents—Dr. H. voN ECKERMANN, Dr. A. HARKER, F.R.S., Prof. O. T. Jones, F.R.S., Sir ALBERT SEWARD, F.R.S., Prof. C. E. Tittry, F.R.S., Prof. L. J. WILts. Recordev.—l. S. DOUBLE. Secretavies.—Dr. O. M. B. Burman, W. H. WILcockson. Local Secretary.—M. BLAck. D.—ZOOLOGY. President.—Dr. S. W. Kemp, F.R.S. Vice-Presidents.—Prof. L. F. DE BEAuForRT, Prof. H. Boscuma, Prof. F. A. E. Crew, Prof. J. STANLEY GARDINER, F.R.S., Prof. J. Gray, F.R.S., Dr. A. D. Imns, F.R.S., Dr. TH. MORTENSEN. Recorder.—Prof. W. M. TATTERSALL. Secretavies.—Dr. G. S. CARTER, H. R. HEWER. Local Secretavy.—Dr. F. S. J. HoLricx. E.—GEOGRAPHY. President.—Prof. GRIFFITH TAYLOR. Vice-Presidents.—Prof. F. DEBENHAM, O.B.E., B. B. Dickinson, Prof. C. B. Fawcett, Lt.-Col. L. TEBBuTT. Recordey.—J]. N. L. BAKER. Secretavies.—Dr. R. O. BucHANAN, D. L. LINTON. - Local Secretavy—J. A. STEERS. F.—ECONOMICS. President.—R. F. Harrop. Vice-Presidents.—Sir W. BEVERIDGE, K.C.B., Dr. C. R. Fay, Prof. P. SARGANT FLORENCE, Dr. J. N. Keynes, Mrs. M. MARSHALL. Recordey.—Dr. P. Forp. Secretavies.—S. R. DENNISON, E. D. McCatium. Local Secretary.—D. G. CHAMPERNOWNE. OFFICERS OF SECTIONS, 1938 ix G.—ENGINEERING. President.—Prof. R. V. SOUTHWELL, F.R.S. Vice-Presidents—O. Borer, Sir ALEXANDER GipB, G.B.E., C.B., F.RS., Prof. C. E. Incuis, O.B.E., F.R.S., C. C. Mason. Recordey.—Wing-Commander T. R. CavE-BROWNE-CavVE, C.B.E. Secretavies—H. M. Crarke, Prof. W. J. Joun. Local Secretary.—Dr. R. D. Davigs. H.—ANTHROPOLOGY. President.—Prof. V. GORDON CHILDE. Vice-Presidents—L. C. G. CLARKE, Dr. A. C. Happon, F.R.S., Prof. J. H. Hutton, C.I.E., Prof. E. H. Minns, F.B.A. Recorder.—R. U. SayYce. Secretaries.—Miss C, FELL, K. H. Jackson. Local Secretary.—Dr. G. E. DANIEL. J.—PSYCHOLOGY. President.—Dr. R. H. THOULEss. Vice-Presidents.—Prof. F. C. BartLett, F.R.S., R. J. Bartrett, Dr. Mary Coxuins, E. FARMER, Prof. H. S. LANGFELD, Prof. A. MIcHoTTE. Recordey.—Dr. S. J. F. PHILport. Secretarvies.—Dr. HitpA OLpDuaM, Dr. P. E. VERNON. Local Secretary.—Miss M. D. VERNON. K.—BOTANY. President.—Prof. W. STILEs, F.R.S. Vice-Presidents.—G. E. Brices, F.R.S., Prof. F. T. Brooxs, F.R.S., Sir Roy Rosinson (Chairman, Dept. of Forestry, K*), Prof. E. J. Sarispury, F.R.S., Sir ALBERT SEWARD, F.R.S., W. L. Taytor, Dr. H. H. Tuomas, F.R.S. Recordey.—Dr. B. Barnes. Secretaries.—Prof. T. M. Harris, C. H. THompson, T. THomson, Dr. S. WILLIAMS. Local Secretary.—G. C. Evans. L.—EDUCATIONAL SCIENCE. President.—J. SARGENT. Vice-Presidents—Prof. E. BARKER, A. R. ForpHam, G. F. Hicxson, Prof. G. R. Owst, H. G. WELLs, D.Litt. Recordery.—A. GRAY JONES. Secretaries —S. R. Humpy, N. F. SHEPPARD. Local Secvetary.—J. O. Roacu. M.—AGRICULTURE. President.—Prof. R. G. STaPLEDON, C.B.E. Vice-Presidents.—J. M. Catz, J.S. CH1vEers, Sir Wm. DAMPIER, BOR: S) erot hod. ENGLEDOW. Recordey.—W. GODDEN. Secretary.—G. V. Jacks. Local Secretary —F. HaNLEy. CONFERENCE OF DELEGATES OF CORRESPONDING SOCIETIES. President.—Rt. Hon. the EARL oF OnsLow, C.B.E., P.C., F.S.A. Secretary.—Dr. C. TIERNEY. ANNUAL MEETINGS TABLE OF Date of Meeting 1831, Sept. 27...... 1832, June ig ... 1833, June 25 1834, Sept. 8 1836, Aug. 22 F 1837, Sept. II...... (838, Aug. Io...... 1839, Aug. 26...... | 1840, Sept. 17 .... 1841, July 20 1842, June 23 1843, Aug. 17 1844, Sept. 26...... 1845, Junerg .. | 1846, Sept. Io...... 1847, June 23. .| Dublin... .| Cambridge bel Oxfords. i cces Where held Presidents Mark: nevastvaccersp ieee Viscount Milton, D.C.L., F.R.S. ...... Oxtord ... ..| The Rev. W. Buckland, F.R.S. ...... Cambridge .. .| The Rev. A. Sedgwick, F.R\S. ......... Edinburgh .. Bristol... Liverpool Newcastle-on-Tyne Birmingham Glasgow Plymouth .. Manchester.. Southampton ... "| The Rev. Provost Lloyd, LL.D.,F.R.S .| The Marquis of Lansdowne, F.R.S. "| The Earl of Rosse, F.R.S. .| The Rev. G. Peacock, D.D., F.R. Sir T. M. Brisbane, D.C.L., F.R.S. The Earl of Burlington, F.R.S.......... ‘The Duke of Northumberland, F.R.S. The Rev. W. Vernon Harcourt, F.R.S. The Marquis of Breadalbane, F.RS. The Rev. W. Whewell, F.R. s. The Lord Francis Egerton, F.G.S Chrue Sir John F. W. Herschel, Bart., F.RS. Sir Roderick I. Murchison, Bart. ay Re | Sir Robert H. Inglis, Bart., F.R.S. S The Marquisof Northampton, Pres.R.S. 1848, Aug. 9 ...... Swansea ..... ce | 1849, Sept. 12..... Birmingham .| The Rev. T. R. Robinson, D.D., F.R.S. | 1850, July 2r...... Edinburgh .. ..| Sir David Brewster, K. He ERGte = PeESS aL ULY 2.0.03. Ipswich .| G. B. Airy, Astronomer Royal, F.R.S. eiS52, cept. X ...... Belfast .| Lieut.-General Sabine, F.R.S. | 1853, Sept. 3 ...... TEI ES aes ..| William Hopkins, F.R.S... 1854, Sept. 20...... Liverpool .| The Earl of Harrowby, F.R.S. / 1855, Sept. 12 .| Glasgow .. The Duke of Argyll, F.R.S. ............ | 1856, Aug. 6 ‘| Cheltenham .., Prof.C.G.B.Daubeney, M.D.,F.R.S. . | 1857, Aug. 26...... Dublin........ .| The Rev. H. Lloyd, D.D., F. Rise | 1858, Sept. 22...... Leeds ...... Richard Owen, M.D., D. Cr , F.R.S. | 1859, Sept. 14...... Aberdeen H.R.H. The Prince Consort .......++0+- | (860, June 27 ...| Oxford ..... The Lord Wrottesley, M.A., F.R.S. | 1861, Sept. 4 ......| Manchester... .| William Fairbairn, LL.D., F.R.S.... Weeos Oct. eer. Cambridge ............ The Rev. Professor W illis, "M.A. ,F.R.S 1863, Aug. 26...... Newcastle-on-Tyne | Sir William G. Armstrong, C. B., F.R.S 1864, Sept. 13...... DOU Sencancenveacenaese Sir Charles Lyell, Bart., M.A., F.R.S 1865, Sept. 6 ......| Birmingham .. .| Prof. J. Phillips, M.A., LL.D., F.R.S 1866, Aug. 22 Nottingham .. ..| William R. Grove, Q.C., F.R.S. ... 1867, Sept. 4 ...... Dundee ..... .| The Duke of Buccleuch, K.C. B.,F.R.S 1868, Aug. I9...... Norwich Dr. Joseph D. Hooker, F.R.S. ........ 1869, Aug. 18...... Exeter ... Prof. G. G. Stokes, D.C.L., F. 1870, Sept. 14...... Liverpool .. Prof. T. H. Huxley, LL. COP I AUPS 2 Uecenes Edinburgh Prof. Sir W. Thomson, L nis 1872, Aug. 14...... Brighton Dr. W. B. Carpenter, FEURS ees 1873, Sept. 17...... Bradford Prof. A. W. Williamson, F.R.S e. 1874, Aug. 19 Belfast Prof. J. Tyndall, LL.D., F.R.S. 1875, Aug. 25 Bristol Sir John Hawkshaw, F.R.S. 1876, Sept. 6 Glasgow Prof. T. Andrews, M.D. oy R.S. 1877, Aug. I5...... Plymouth ..| Prof. A. Thomson, M.D., F.R.S 1878, Aug. 14...... Dublin...... .| W. Spottiswoode, M.A. ela shee 1879, Aug. 20...... Sheffield ..| Prof. G. J. Allman, M.D., F.R.S. | 1880, Aug. 25...... Swansea .| A. C. Ramsay, LL. Ds ty See meen 1881, Aug. 31...... Niorkiyy cesta. eee Sir John Lubbock, Ba art., F.R.S. 1882, Aug. 23...... Southampton ...... Drews Siemens, Pee rectacesccctsnen | 1883, Sept. r9...... Southport! 228, ..-0.s< Prof. A. Cayley, D. en, A aCe ra 1884, Aug. 27...... Montreal ..| Prof. Lord Rayleighy Bult peusst dees ies 1885, Sept. 9 Aberdeen ..... .| Sir Lyon Playfair, K.C.B., F.R.S. ... 1886, Sept. 1 Birmingham .. Sir J. W. Dawson, C.M.G., S. 1887, Aug. 31 Manchester Sir H. E. Roscoe, D.C.L., F. 1888, Sept. 5 ...... Bathiiecssnascnesececers Sir F. J. Bramwell, IBERES Ss 3, 1889, Sept. I1...... Newcastle-on-Tyne | Prof. W. H. Flower, C.B:, F. 1890, Sept. 3 ...... Leeds Sir F. A. Abel, C.B., F.R.S. 1891, Aug. I9...... Gardifie sce .| Dr. W. Huggins, F. R. Si 3 1892, Aug. 3 ...... Edinburgh ..... Sir A. Geikie, LL.D., F. RS. 1893, Sept. 13 Nottingham ..| Prof. J.S. Burdon Sanderson, F.R.S. 1894, Aug. 8 ...... Oxford .| The Marquis of Salisbury, K. Gs F.R.S. 1895, Sept. 11...... Ipswich . ..| Sir Douglas Galton, K.C.B., F. RSs | 1896, Sept. 16 iverpool .| Sir Joseph Lister, Bart., Pres, RS. . | 1897, Aug. 18 Toronto . Sir John Evans, K.C.B., F.R.S. ..... | 1898, Sept. 7 .| Bristol Sir W. Crookes, F.R.S. ........ 1899, Sept. 13...... Dover .| Sir Michael Foster, K.C.B. | * Ladies were not admitted by purchased tickets until 1843. Old Life | New Life Members | Members er dele Pt tal Hcleal Si ichislinth deste 169 65 303 169 109 28 226 150 313 36 241 10 314 18 149 3 227 12 235 9 172 8 164 10 141 13 238 23 194 33 182 14 236 15 222 42 184 27 286 21 321 113 239 15 203 36 287 40 292 44 207 31 167 25 196 18 204 21 314 39 246 28 245 36 212 27 162 13 239 36 221 35 173 19. 201 18 184 16 144 11 272 28 178 17 203 60 235 20 225 18 314 25 428 86 266 36 277 20 259 21 189 24 280 14 201 57. 327 21 214 13 330 st 120 8 281 19 296 20 + Tickets of Admission to Sections only. [Continued on p. Xii. ANNUAL MEETINGS _ ANNUAL MEETINGS. Old eg Mol an 2 327 324 ; | i j ; New ' Annual | Annual Members Members | bo | } Sums paid Amount P Asso- | yadies | Forei received | 0” account biicintes adies fe ears Total fon of Grants | | Tickets for Scientific | | | Purposes | ral | aa aa | 353 = — } ea — ,; = | 900 a = | — — —_— 1298 _ £20 0 0 | == => | = | _ —_ | 167 0 Oo | = Fel BO} MERSBO == 435 0 0 | = — — 1840 = ig 022/22) V6 | _ II1O*. +} — | 2400 — 932 2 2 = er 34 | 1438 = 1595 II o = = 40 1353 ar 1546 16 4 _ 60* _ 891 — | 1235 I0 11 33t 331* 28 1315 = | 1449 17 8 —_ 160 —_ —_ —_ | 1565 I0 2 | ot |. 260° | —_ _ _— | 981 12 8 | 407 172 35 1079 = 831 9 9 270 196 36 857 — 685 16 o 495 203) jinin’53 1320 Tar 208 5 4 376 197 15 Brg, |, £797" 0410 7275 1 8 | 447 237 22 1071 963 0 0} 15919 6 510 273 44 1241 1085 0 0 345 18 oO 244 | I4I 37 710 620 0 0} 39% 9 7 510 292 | 9 1108 | 1085 0 o 304 6 7 367 236 6 | 876 | 903 0 Oo 205 0 O 765 524 10 | 1802 | 1882 0 o| 38019 7 1094 543 26 hy rae) | 23x0.o oe) 480 16 4 412 346 ores 1098 0 0} 734 13 9 goo 569 26 | 2022 | 2015 0 oO 507 15 4 710 509 13 1698 | 1931 0 0 618 18 2 1206 821 22 | 2564 | 2782 0 oO 684 Ir 1 636 463 47 1689 | 1604 0 oO 766 19 6 1589 791 15 | 3138 3944 0 ©O|} IIII § Io 433 242 25 |} 16x | 1089 O oO} 1293 16 6 1704 1004 25 | 3335 | 3640 0 o| 1608 10 1119 1058 13 | 2802 2965 o o| 1289 15 8 766 508 23 1997 2227 0 0.) 1591 °7 10 60 771 Ir 2303 2469 0 0Oj| 175013 4 1163 771 77 2444 2613 0 o| 1739 4 0 720 682 45t | 2004 2042 0 0| 1940 0 O 678 600 17 ' 1856 I93I O o]| 1622 0 Oo 1103 g10 14 2878 3096 0 oO} 1572 0 0 976 754 21 2463 | 2575 0 O| 1472 2 6 937 giz | 43. 2533 2649 0 O| 1285 0 Oo 796 | 601 II 1983 2120 0 o| 1685 0 o 817 630 12 1951 1979 0 O| II5I 16 0 884 672 17 2248 2397 0 0| 960 0 o 1265 712 25 2774 3023 0 O| 1092 4 2 446 283 Ir 1229 3268. 6 0.) 3126, 9 7 1285 674 17 2578 2615 0 Oo 725 16 6 529 349 13 1404 1425 0 ©| 1080 11 I1 389 147 12 915 899 © O| 731 7 7 1230 514 24 2557 2689 0 Oo 476 8 1 516 189 21 1253 1286 o 6} 1126 ¥ II 952 841 5 _ | 2714 | 3369 © 0 | 1083 3 3 826 74 26&60H.§ 1777 1855 0 o| 1173 4 0 1053 447 6 2203 2256 0 o| 1385 0 Oo 1067 429 II 2453 2532 0 0 995 © 6 1985 493 92 3838 4336 0 oO} 1186 18 o 639 509 12 1984 2107 0 O/] I5II O 5 1024 | 579 21 2437 2441 O O|} 1417 OIL 680 | 334 12 1775 | 1776 0 0} 78916 8 672 | 107 35 1497 1664 © ©O| 1029 10° 0 733 439 50 2070 2007 0 Oo 864 10 o 773 268 17 1661 1653 0 Oo 907 15 6 O4r | 45% 77 2321 2175 0 O 583 15 6 493 261 22 1324 1236 0 0 O77 115, 5 1384 | 873 41 3181 3228 o ©O| rro4 6 1 682 100 41 1362 1398 o oO} 1059 10 8 1051 639 33 2446 2399 0 O/| 1212 0 0 548 1z0 SO 27 1403 1328 0 O| 1430 14 2 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 § Fellows of the American Association were admitted as Hon. Members for this Meeting. [Continued on p. xiii. xii ANNUAL MEETINGS Table of Date of Meeting Where held Presidents id te Ney tie 1900, Sept. 5 .....- Bradford ..........+. Sir William Turner, D.C.L., F.R.S. ...| 267 13 1gor, Sept. 11...... Glasgow .... ...| Prof. A. W. Riicker, D.Sc., Sec. R.S. 310 37 1902, Sept. 10...... Belfast ...| Prof. J. Dewar, LL.D., F.R.S. ......... 243 21 1903, Sept. 9 Southport .... .| Sir Norman Lockyer, K.C.B., F.R.S. 250 2I 1904, Aug. 17 Cambridge .... Rt. Hon. A. J. Balfour, M. P., FURS;.. 419 32 1905, Aug. 15. South Africa Prof. G. H. Darwin, LL.D., F.R.S. ... 115 40 1906, Aug. 1 . Yor .| Prof. E. Ray Lankester, LL.D., F.R.S. 322 Io 1907, July 31 ......| Leicester .| Sir David Gill, K.C.B., F.R.S. 276 19 1908, Sept. 2 ...... Dublin......... ..-| Dr. Francis Darwin, ERS. 294 24 1909, AUg. 25 .....- Winnipeg . ...| Prof. Sir J. J. Thomson, F.R.S. 117 13 1g10, Aug. 31...... Shetfield ...... ....| Rev. Prof. T. G. Bonney, F.R.S. 293 26 Igt1, Aug. 30...... Portsmouth ...| Prof. Sir W. Ramsay, K.C.B., 3. 284 21 1912, Sept. 4 ...... Dundee ......... ...| Prof. E. A. Schafer, F.R.S. ......ee.0ee 288 14 1913, Sept. I0...... Birmingham ....| Sir Oliver J. Lodge, F.R.S. 4 376 40 1914, July-Sept. | Australia......... ...| Prof. W. Bateson, F.R.S. ..... ae 172 13 1915, Sept. 7 ...- Manchester ......... Prof. A. Schuster, F.R.S........ mupedus asialt 242 19 1916, Sept. 5 ...... Newcastle-on-Tyne | ) 164 12 1917 No Meeting) ...... , Sir Arthur Evans, F.R.S. ............ — _— 1918 No Meeting) ...... | — — 1919, Sept. 9...... Bournemouth......... Hon. Sir C. Parsons, K.C.B., F.R.S....) 235 47 1920, Aug. 24...... ...| Prof. W. A. Herdman, C.B.E., F.R.S. 288 II 1921, Sept. 7 ...... .| Sir T. E. Thorpe, C.B., F.R.S. ......... 336 9 1922, Sept. 6 ...... Hull Sir C.S. Sherrington, G.B.E., Pres.R.S.| 228 13 1923, Sept. 12...... Liverpool Sir Ernest Rutherford, F.R.S. ......... 326 12 1924, Aug.6 . Toronto ......... ...| Sir David Bruce, ae ees saeeke 119 7 1925, Aug. 26. Southampton .| Prof. Horace Lamb, F.R ade 4 280 8 1926, Aug. 4 Oxford . H. Spa The Prince of ‘Wales K.G., ose i 358 9 1927, Aug. 31 ...... MCCS jecaccccscnveencans Sir Arthur Keith, ERS. es 249 9 1928, Sept. 5 ...... Glasgow ...... ...| Sir William Bragg, KUB-E.“ ERISA. 260 10 1929, July 22 ...... South Africa Sir Thomas Holland, K.C.S.1., Les Py ha, UE SOS sce eroereecreoneeee 81 I 1930, Sept. 3 ...... MBYIStOMS cacveupsanesvss Prof. F. O. Bower, F.R.S. ............... 221 5 1931, Sept. 23...... London’ <..2:c0.:.05+0. Gen. the Rt. Hon. J. C. Smuts, P.C., } COHISREG i cncensaeaseenccseetpcntesencss 487 xaee 1932, Aug. 31...... NMOL) teecssseperasessnes Sir Alfred Ewing, K.C.B., F.R.S. 206 re 1933, Sept. 6 ...... Leicester ............| Sir F. Gowland Hopkins, Pres. R.S.. 185 37 1934, Sept. 5 «s+. i -eee| Sir James H. Jeans, F.R.S.'4.......... 24 199 21 | 1935, sept. 4 «....- .| Prof. W.W. Watts, F.R.S......... at I9gI II 1936, Sept. 9 ...... : Sir Josiah Stamp, G.C.B., G.B.E....... 188 10 19975 DEDE.L tuwaene Nottingham ....| Sir Edward B. Poulton, F.R.S. ......... 213 6 1938, Aug. 17...... Cambridge .......+..++ Rt. Hon. Lord Rayleigh, F.R.S.......... 263 a5i6 1 Including 848 Members of the South African Association. 2 Including 137 Members of the American Association. e 2 Special arrangements were made for Members and Associates joining locally in Australia, see Report, 1914, p. 686. The numbers include 80 Members who joined in order to attend the Meeting of L’Association Frangaise at Le Havre. « Including Students’ Tickets, ros. * Including Exhibitioners granted tickets without charge. : * Including grants from the Caird Fund in this and subsequent years, ' Including Foreign Guests, Exhibitioners, and others. ANNUAL MEETINGS xiii Annual Meetings—(continued). | Sums paid Old New INR poe on account Annual Annual ine Ladies /|Foreigners} Total z f ay of Grants | Year Members Members| © Tickets for Scientific Purposes ee Se ————_— — —— 207 45 | 801 482 9 1915 |£1801 0 o |f1072 10 0o | 1900 374 131 794 246 20 Igi2 2046 0 0 920 9 II | Igor 314 86 647 305 6 1620 1644 0 0 947 0 O| I902 319 (ole) 688 365 21 1754 1762 0 0 845 13 2 | 1903 449 113 1338) 317 121 2789 2650 0 O 887 18 II | 1904 937! 411 430 | 181 16 2130 2422 0 0 928 2 2] 1905 356 93 SIZe" | 352 22 1972 ISIT +O) 40: 882 0 9g | 1906 339 61 659 251 42 1647 1561 0 0 757 12 10 | 1907 465 112 1166 222 14 2297 2317 0 O| 1157 18 8 | 1908 290? 162 789 go 7 1468 1623 0 O|} 1014 g 9] 1909 379 57 563 123 8 1449 1439 0 0 963 17 0] IgI0 349 61 vi ta 81 31 1241 1176 0 Oo 922 0 OO] I9g1II 368 95 1292 | 359 88 2504 2349 0 O 845 7 6] 1912 480 149 1287 | 291 20 2643 2756 0 O 978 17 I | 1913 129 4160° 539° a 21 5044° | 4873 0 O| 1861 16 4°} 1914 287 116 6284 141 8 1441 1406 0 0} 1569 2 8/ 1915 250 76 251° 73 —_— 826 821 0 0} 985 18 10 | 1916 _ _ _ — _ _ _ 677 17 2 I917 — _ — _— _ _ _ 326 13 3] 1918 254 102 6884 153 3 1482 1736 0 O 410 0 0O| IgI9 Annual Members Old Annual Te ae ona Students’ wResular | Meeting | Meeting | Tickets | Tickets Report only 136 192 571 42 120 20 1380 1272 10 0| 1251 13 0*| 1920 133 410 1394 121 343 22 2768 2599 15 Oo 518 xX 10] 1921 90 294 757 89 235° 24 1730 | 1699 5 O| 722 0 7 | 1922 Compli- mentary? 123 380 1434 163 550 308 3296 | 2735 15 ©} 777 18 6°| 1923 37 520 1866 41 89 139 2818 3165 19 Of! 1197 5 9 | 1924 97 264 878 62 119 74 1782 1630 5 OO] 1231 O O|} 1925 Ior 453 2338 169 225 69 3722 3542 0 0 917 I 6] 1926 84 334 1487 82 264 161 2670 2414 5 0 761 10 O| 1927 76 554 1835 64 201 74 3074 3072 I0 0 | 1259 10 O | 1928 24 177 12274 —_— 161 83 1754 1477 15 O| 2193 2 I | 1929 68 310 1617 97 267 54 2639 2481 15 Oo 631 Ir g | 1930 78 656 2994 157 454 449 5702 | 4792 10 0 | 1319 9 6 | 1931 44 226 1163 45 214 125 2024 1724 5 O|} 1218 13 11 | 1932 39 236 1468 82 147 74 2268 2428 2 0| 562 19 1133} 1933 30 273 1884 181 280 7o 2938 2900 13 6| 1423 4 9 | 1934 29 237 -| 1444 142 107 7o 2321 2218 14 6] 1649 2 4 | 1935 29 257 1184 128 178 93 2067 2006 14 0] 1098 £r 1 | 1936 28 290 1096 102 200 92 2027 1883 12 0 720 15 I | 1937 32 355 1932 53 209 114 2983 3072 I9 O| 1066 6 8 | 1938 * The Bournemouth Fund for Research, initiated by Sir C. Parsons, enabled grants on account of scientific purposes to be maintained. ® Including grants from the Caird Gift for research in radioactivity in this and subsequent years to 1926. 19 Subscriptions paid in Canada were $5 for Meeting only and others prorata; there was some gain on exchange. 11 Including 450 Members of the South African Association. 12 Including 413 tickets for certain meetings, issued at 5s. to London County Council school-teachers. 18 For nine months ending March 31, 1933. 14 Sir William B. Hardy, F.R.S., who became President on January 1, 1934, died on January 23. 15 Including 8 representatives of Corporation Members. NARRATIVE OF THE CAMBRIDGE MEETING. On Wednesday, August 17, at 8.30 p.M., the Inaugural General Meeting was held in the Regal Cinema, when the Vice-Chancellor of the University of Cambridge (Prof. H. R. Dean, M.D.) and His Worship the Mayor of Cambridge (Councillor E. Saville Peck, M.A.) welcomed the Association to Cambridge. ‘The President of the Association, the Rt. Hon. Lord Rayleigh, F.R.S., delivered an address entitled: (Part I) Viston in Nature and Vision aided by Science, (Part 11) Science and Warfare, for which see p. 1. A vote of thanks to the President was proposed by Sir Joseph J. Thomson, O.M., F.R.S., Master of Trinity College, and seconded by Dr. G. D. Birkhoff, Past President of the American Association for the Advancement of Science. Evening Discourses were delivered to the members as follows : (1) Friday, August 19, in the Arts Theatre, Peas Hill, Dr. H. Godwin : The History of the Fens. (See p. 535.) (2) Monday, August 22, in the same theatre, Prof. M. L. Oliphant, F.R.S.: The Contribution of the Electrical Engineer to Modern Physics. (See p. 536.) On Tuesday, August 23, at 8.30 P.M., in the Reception Room (Examina- tion School), members of the Scientific Delegation in India, 1937-38, spoke of the experiences of the Delegation. Sir James Jeans, F.R.S., General President of the Indian Science Congress Association for its Jubilee meeting, was in the chair, and the other speakers were Dr. C. G. Darwin, F.R.S., Dr. J. A. Venn, Prof. Winifred Cullis, C.B.E., Prof. J. H. Fleure, F.R.S., and Prof. W. W. Tattersall. A series of lantern slides from photographs by the late Dr. A. E. H. Tutton, F.R.S., was shown. Photographs by delegates were on exhibition in the Reception room throughout the Cambridge Meeting. For a oie on the proceedings of the Delegation, see p. xxvi. A summary of Sectional Transactions on August 18-24 will be found on pp- 381 and following. On Thursday evening, August 18, a Reception was given by the Vice- Chancellor on behalf of the University of Cambridge, in the Senate House and Old Schools. By kind permission of the Master and Fellows of Gonville and Caius College there was dancing in the hall of that college. NARRATIVE OF THE CAMBRIDGE MEETING XV On Tuesday afternoon, August 23, the Mayor and Mayoress of Cam- bridge (Councillor and Mrs. E. Saville Peck) entertained members at a Sherry Party, held in Emmanuel College by kind permission of the Master and Fellows. Garden Parties were given at the following Colleges: Downing and Sidney Sussex (August 19), Christ’s and Queens’ (August 22); and in- formal evening conversaziones were held at Trinity College (August 19) and St. John’s College (August 22). On Saturday, August 20, general excursions were arranged as follows, with the co-operation of institutions and individuals whose premises were visited : (1) King’s Lynn, Castle Rising, and Sandringham (by gracious per- mission of H.M. The King). (2) Hengrave Hall, Bury St. Edmund’s, Lavenham, Long Melford. (3) Tring Museum, London Gliding Club, and works of Stonehenge Bricks, Ltd. An additional visit was arranged to Whipsnade Zoological Park through the courtesy of the Zoological Society of London. (4) Ely, Sutton, and Earith. (5) Audley End, Saffron Walden, and Thaxted. Visits were arranged to colleges and to many other points of interest in Cambridge, and to the works of the British Portland Cement Manu- facturers, Ltd., the Cambridge Instrument Co., Ltd., Messrs. Chivers & Sons, Ltd., Messrs. Pye Radios, Ltd., and Messrs. Towgood and Sons and Dufay-Chromax, Ltd. Other excursions and visits devoted to the interests of particular sections are mentioned among the Sectional Trans- actions in later pages. _The official sermon was preached by the Rt. Rev. the Lord Bishop of Winchester in Great St. Mary’s Church on Sunday morning, August 21. An exhibition of paintings and other objects of art by members of the Association was on view throughout the period of the Meeting. At the final meeting of the General Committee on Wednesday, August 24, it was resolved : That the British Association places upon record its deep gratitude for the reception ‘afforded to it by the University, the Borough, and the County of Cambridge. The Association wishes to convey its most cordial thanks to the departments and colleges of the University which have so generously provided accommodation for its meetings and hospitality for its members. Its thanks are due also to the Corporation of the Borough and the County authorities, as well as to the many commercial and industrial institutions in Cambridge and the neighbourhood, for co-operation in the arrangements for the meeting, for generous entertainment, and for the facilities which have been provided for excursions and visits. Finally, the congratulations as well as the gratitude of the Association are offered to the local officers and their efficient helpers, to whose unsparing efforts the brilliant success of the meeting has been due. REPORT OF THE COUNCIL, 1937-38. OBITUARY. The Council have had to deplore the loss by death of the following office-bearers and supporters :— Prof. W. A. Bone, F.R.S. Mr. Hugh Ramage Dr. G. A. Boulenger, F.R.S. Dr. A. B. Rendle, F.R.S.1 Prof. E. W. Brown, F.R.S. Lady Robertson Prof. H. B. Fantham Prof. the Rt. Hon. Lord Ruther- Prof. L. N. G. Filon, F.R.S. ford of Nelson, O.M., F.R.S.t Prof. A. Hutchinson, F.R.S. Sir John Snell, G.B.E. Prof. A. Lodge Miss Edith Stoney Prof. Magnus Maclean Dr. A. E. H. Tutton, F.R.S. Prof. G. H. F. Nuttall, F.R.S. Dr. W. W. Vaughan, M.V.O.1 The Association was represented at Lord Rutherford’s funeral by the President, Sir Edward Poulton, F.R.S. (a pall-bearer), Sir James Jeans, F.R.S., and Prof. A. Ferguson, General Secretary, and at the memorial service in Trinity College Chapel, Cambridge, by Prof. F. T. Brooks, F.R.S., General Secretary, and Prof. F. J. M. Stratton. Dr. W. T. Calman, F.R.S., represented the Association at the funeral of Dr. A. B. Rendle, F.R.S. The President, the Rt. Hon. Lord Rayleigh, F.R.S., and the Secretary, Dr. O. J. R. Howarth, on behalf of the General Officers, represented the Association at the memorial service for Dr. W. W. Vaughan, M.V.O. REPRESENTATION. Representatives of the Association have been appointed as follows :— Meeting held at the House of Lords to dis- cuss the desirability of nature reserves in National Parks (by invitation of the Society for the Promotion of Nature Reserves) . ’ : , ; > Dro vj Ste wblexley: : F.R.S., and Prof. E J. Salisbury, F.R.S. Sub-committee of the International Seismo- logical Association, dealing with the Seismological Summary ; Dr. H. Jeffreys, F.R.S. International Congress of Anthropology . and Ethnology, Copenhagen p Mr. H. J. E. Peake. International Union of Chemistry, Rome . Dr. F. W. Aston, F.R.S. 1 See narrative of the Scientific Delegation in India, annexed to this report. REPORT OF THE COUNCIL, 1937-38 xVil RESOLUTIONS AND RECOMMENDATIONS. Resolutions and recommendations, referred by the General Committee to the Council for consideration, and, if desirable, for action, were dealt with as follows. The resolutions will be found in the Report for 1937, p. xlviii. (2) On a resolution from Section A (Mathematical and Physical Sciences), the Council laid before the Corporation of the City of Nottingham a report on the bad condition of the grave of George Green in Sneinton churchyard in that city, and were gratified to learn that the Corporation had undertaken to restore the grave. (6) On a resolution from Section D (Zoology), the Council com- municated to the Trustees of the British Museum an expression of their hope that the custody of the late Lord Rothschild’s museum at Tring would be undertaken by the Trustees. (c) The Council were informed by the Ministry of Agriculture and Fisheries (i) that the resumption of the publication of one-inch Ordnance Survey maps in the ‘ relief’ style will be considered when the publica- tion of the present Fifth Edition in the ordinary style is nearing com- pletion ; (ii) that with regard to maps showing physical features only the Minister is prepared to arrange for an edition, showing water and contours only, when the ordinary edition of each forthcoming sheet is printed. (Resolution of Section E, Geography.) (d) The General Secretaries were authorised to consult the Secretary of the Institution of Civil Engineers on the subject of a resolution from Section G (Engineering) on the desirability of improving the co-ordination of arrangements for publishing and indexing new engineering knowledge and the results of engineering research. (e) The Council received unofficial information from a representative of the India Office to the effect that, while it was admitted that a knowledge of Anthropology would be of advantage to civil servants, the present syllabus, as reviewed recently by an authoritative committee set up by the Secretary of State, would not allow of the introduction of an additional compulsory subject. The Council therefore decided not to transmit the resolution of Section H (Anthropology) officially to the India Office. (f) In reply to the resolution of Section L (Educational Science) on adult education, the officers of the Board of Education have under- taken to consider the resolution when reports are presented of a survey, at present in operation, of existing provisions for adult education in England and Wales. (g) A resolution for the Conference of Delegates of Corresponding Societies, supported by Section D (Zoology), on the necessity for an inquiry into methods of dealing with rodents and other wild mammals which affect agriculture, was communicated to the Ministry of Agri- culture and Fisheries and to the Department of Agriculture for Scotland. Both departments replied to the effect that experiments on the control of rabbits were already in progress. xviii REPORT OF THE COUNCIL, 1937-38 (h) The Council approved a resolution from the Conference of Delegates of Corresponding Societies on the desirability of establishing through the Corresponding Societies Committee a close liaison with the Association for the Study of Systematics in Relation to General Biology, with a view to the Corresponding Societies undertaking work bearing upon systematic problems. FINANCE. The Council have received reports from the General Treasurer throughout the year. His account has been audited and is presented to the General Committee. The Council made the following grants from funds under their control :-— From the Caird Fund. £ Seismological investigations ; , : ; -1) Go Mathematical tables : : : : : . 200 Critical geological sections ; 3 : : . 25 (contingent) Reduction of noise . ‘ , é , : 10 (contingent) Perseveration and its testing : 5 : b j 10 (contingent) Kent’s Cavern, Torquay . : : ; , : 5 From the Bernard Hobson Fund. Critical geological sections rs 3 : _ , 25 Odlite of Stow-on-the-Wold ‘ : , : ‘ 25 From the Leicester and Leicestershire Fund. Archeology of the Fens . : ; ; : ‘ 25 Transplant experiments. : 3 ‘ 5 Organisation of research in Education” : f : 5 Gaps in the informative content of Education : : 10 From the Norwich Fund. It was reported that a grant of £40, made last year from the Norwich Fund to the Norfolk Research Committee for the investigation of the post-glacial deposits of East Norfolk, would not be required, with the exception of a sum of £2 13s. 9d., the payment of which was authorised. The balance of the fund was granted as follows : — (a) To Mr.J.E. Sainty, to continue eee uons: ontheLong £ s. d. Barrow at West Rudham, Norfolk ; PP agmeei*. O (6) To Dr. A. S. Watt, to continue work on rhythmic phenomena of Breckland plants . : ; : < 20O--.0 Corporation Membership.— Messrs. Metropolitan - Vickers Electrical Company, Ltd., and the Educit’onal Institute of Scotland have been admitted to corporation membership of the Association. REPORT OF THE COUNCIL, 1937-38 xix PRESIDENT (1939), GENERAL OFFICERS, GENERAL COMMITTEE, AND COUNCIL. President (1939).—The Council’s nomination to the Presidency of the Association for the year 1939 (Dundee Meeting) is Sir Albert Seward, F.R.S. The General Officers have been nominated by the Council as follows :— General Treasurer, Prof. P. G. H. Boswell, F.R.S. General Secretaries, Prof. F. 'T. Brooks, F.R.S., Prof. Allan Ferguson. General Committee ——The following have been admitted as members of the General Committee, mainly on the nomination of Organising Sectional Committees under Regulation 1 :— Dr. H. B. Cott Mr. A. Rodger Mr. H. R. Hewer Dr. B. Semeonoff Dr. F. S. J. Hollick Mr. W. J. H. Sprott Dr. R. G. S. Hudson Dr. W. Stephenson Dr. M. M. Lewis Dr. E. C. Stoner, F.R.S. Mr. J. A. McMillan Mr. S. H. Straw Miss A. E. Miller Mr. F.C. Thomas Mr. F. Rayns, O.B.E. Council.—The retiring Ordinary Members of the Council are: Prof. R. N. Rudmose Frown, Mr. H. M. Hallsworih, C.B.E., Pref. G. W. O. Hewe, and Prof. F. E. Weiss, F.R.S., and a further vacancy is created by the death of Dr. W. W. Vaughan, M.V.O. The Council have nominated as new members Mr. R. W. Allen, C.B.E., Prof. F. E. Fritsch, F.R.S., and Sir Richard Gregory, Bt., F.R.S.; leaving two vacancies to be filled by the General Committee without nomination by the Council. The full list of Ord'nary Members nom‘nated is as follows :— R. W. Allen, C.B.E. Prof. A. V. Hill, O.B.E., Sec.R.S. Dr. F. W. Aston, F.R.S. Prof. T. G. Hill Prof. F. Aveling Prof. T. S. Mcore Prof. F. Balfour-Browne Prof. J. C. Philip, O.B.E., F.R.S. Sir T. Hudson Beare Prof. J. G. Smith Rt. Hon. Viscount Bledisloe, P.C., Lt.-Col. W. Campbell Smith G.C.M.G., G.B.E. Dr. C. Tierney Dr. W. T. Calman, C.B., F.R.S. Dr. J. A. Venn Prof. F. Dekenham, O.B.E. Prof. Sir Gilbert Walker, C.S.I., Prof. W. G. Fearnsides, F.R.S. FR.S: Piof. H. J. Fleure, F.R.S. R. S. Whirple Piof. F. E. Fritsch, F.R.S. J. S. Wilson Sir Richard Gregory, Bt., F.R.S. Future MEETINGS. Dundee has been already determined by the General Committee as the place of meeting in 1939. The dates now proposed for the Dundee Meeting are August 30 to September 6. There have been received invitations for the Association to meet in xx REPORT OF THE COUNCIL, 1937-38 Newcastle-upon-Tyne in 1940, in Belfast in 1941 or any year nearly following, in 1942 in Birmingham. As previously reported, there is also an invitation to meet in Swansea in any convenient year. In view of informal discussion as to the possibility of an invitation from Australia for the year 1942, the General Committee should be made aware that such an invitation will not be forthcoming. MISCELLANEA. Scientific Delegation in India.—A narrative report of the activities of the Scientific Delegation in India is annexed to this Report of the Council. Proposed Overseas Delegation Fund—The General Committee last year granted a sum not exceeding {£1,000 from the general funds of the Association towards the expenses of the Scientific Delegation in India. In the event, it was necessary to use only £217 of thissum. The Council, recognising the great success of the Indian visit, and believing that similar opportunities may arise to send delegations elsewhere, and that, if arising, advantage should by all means be taken of them, now recommend to the General Committee that the unexpended balance of the above grant should be held as the nucleus of a fund from which to assist expenses of such delegations. British Science Guild Lectures—Prof. H. L. Hawkins was appointed to deliver the Alexander Pedler Lecture for 1939 at the Worthing Congress of the South-Eastern Union of Scientific Societies, and did so on June 24. Dr. H. Spencer Jones, F.R.S., was appointed to deliver the Norman Lockyer Lecture on December 6. British Science Guild: South Australian Handbooks.—Following upon the incorporation of the Guild into the Association, the important Work of the Handbooks Committee of the South Australian branch of the Guild was brought to the notice of the Council, and it was resolved that, while no financial aid could be offered to assist in the production of forth- coming books, an expression of the Council’s ‘ appreciation of the great value of the handbooks of the flora and fauna of South Australia’ should be recorded and conveyed to the Committee. Geology in Schools.—During the past year the Association’s two reports on the teaching of geology in schools have been distributed to appropriate educational authorities, together with an expression of the Council’s hope that careful consideration would be given to the question of in- troducing geology into the school curriculum, either by inclusion in a course of general elementary science or as a separate subject. Discussion on Planning the Land of Britain —Reprints of this discussion, which took place at the Nottingham Meeting last year and appears in the Report of that Meeting, have been widely circulated to planning authorities and organisations interested in this subject. Scientific Advisory Committee of the Trades Union Congress.—The - Trades Union Congress asked for the co-operation of the Association in proposing names of scientific workers who might be invited by the Congress to serve on a Scientific Advisory Committee. The General REPORT OF THE COUNCIL, 1937-38 xxi Officers were authorised to advise the representatives of the Congress informally in this matter. Reports on a Division for Social and International Relations of Sctence, and a Publication —The Countil have approved in principle, and recom- mend, the establishment of a Division of the Association to deal with the social and international relations of science. A Ccmm‘ttee was appointed to formulate a scheme for the working of this Division. The same Ccmmittee was instructed to consider and report upon present methods of publication by the Association, and to suggest alternative methods if thought desirable. The reports of this Committee are appended hereto. Down House. The following report for the year 1937-38 has been received from the Down House Committee :— The number of visitors to Down House during the year ending June 6, 1938, has been 7,185, compared with 6,148 in 1936-37. A number of valued gifts have been added to the collection during the past year. Sir Buckston Browne acquired and presented a portrait of Darwin in oils, by E. Pailthorp, apparently made from a photograph already in the collection, as Darwin is believed to have sat only to Ouless and Collier. Sir Buckston Browne also collected photographs of members of Darwin’s family, which, have been framed together. He received from Mr. Sidney Spokes, M.R.C.S., a copy of the second edition of Lyell’s Elements of Geology, on a flyleaf of which there appears in Lyell’s hand the note: ‘ Darwin recommends a short chap. on metallic veins, giving the present state of our knowledge. He denies seeing a beginning to each crop of species. Jan. 26, 1842.’ With this volume is now shown one of Lyell’s geological hammers, presented by Miss D. Pertz. Darwin’s aneroid barometer now hangs again in the old study, through the generosity of Miss Hooker. Prof. F. W. Oliver, F.R.S., has presented an important series of letters, which his father, Prof. Daniel Oliver, F.R.S., had from Darwin. Mr. T. M. Ragg gave a reproduction of a portrait of Fitzroy, commander of H.M.S. Beagle. Sir Josiah Stamp presented a reproduction of the armorial bearings of the Association in stained glass. The statuette of Darwin, mentioned in last year’s report as by an unknown artist, has been recognised as a studio model by Horace Montford: no statue appears to have been executed from it. A new edition of the Catalogue has been prepared and will be brought into circulation shortly. Rainfall is now read regularly from the standard gauge. The total precipitation last year (1937) was 39°12 in., but as the standard gauge was not in use in the first half of the year, no return was made to the Meteoro- logical Office. By way of contrast, it may be mentioned that the rainfall in January to March, 1937, was over 15 in.; in January to March, 1938, it was 5 in., of which 3:54 in. fell in January, 0°895 in February, and 0-565 in March. The Committee were glad to hear of the visit of a party to the House on May 27 in connection with the celebration of the 150th anniversary of the foundation of the Linnean Society. The following financial statement shows income and expenditure on account of Down House for the years ending March 31, 1937 and 1938 :— xxii REPORT OF THE COUNCIL, 1937-38 Corresponding Income figures, 1936-37 PRRE NK GE eae SS. By Rents receivable : : : ‘ T3005, 70 I4I oO oO ,, Income Tax recovered : : : 077, ROTO 168 I 6 ,, Interest and Dividends 807515, 0 CLF 2" 0 ,, Donations 3789 ler », dale of Catalogues, Postcards and Photo- graphs . : ; 26118254. PAS} ohm! ,, Pilgrim Trust Grant . : : : I50 0 0 I50 0 O », Instalment of Grant from Herbert Spencer Bequest . 366 9 Oo DR ja. ,, Balance, being excess of expenditure over income for the year, transferred to Suspense Account : : : 50 I 2 — £1,720 15 3° Sidgaee 25-8 Corresponding Expenditure figures, 1936-37 To Wages of Staff . : 2 : : 822 8 10 803 19 7 ,, Rates, Insurance, etc. j 3 ; Ti Ones 69 5 6 2 Heating, etc. ‘ 175) 0) 7 138 14 8 ,, Lighting and Drainage (including oil and petrol) . : OI 7 FQ ATL », Water ! : F : 14 Oe ee b Oy) A ois ,, Repairs and Renewals | : ; P AZo 3° AE T5ON aaa ,» Garden and Land: Materials and Maintenance . : : 61 8 5 4519 8 ,, Donations to Village Tnstitutions i : Si SO ian a », Household Requisites, etc. . : ; 12) 15 MrT I5 18 ro ,, Transport and Carriage ; ; 3 14 10 TATO 6 ,, Printing, Postages, Telephone and Stationery . ; BEL BU Le) Bis a Aa | », Sundries (non- recurrent) ; — 915 8 ,, Balance, being excess of income over expenditure for the year, transferred to Suspense Account : F : — 55 15 OT £1,720 15 93)" £1, 4g 1S. Thanks to the grant of £500 by the Council from the Spencer Bequest, it has been possible to carry out important repairs and renovations during the past two years without drawing upon the general funds. This sum has now been expended. As the Council are already aware, the Pilgrim Trustees have made a final grant of £150, payable as to £100 and Us 50 in the two ensuing financial years respectively. The Council desire to commend, and to bring to the notice of Members of the General Committee and others, a proposal which has received the . approval of the Down House Committee that steps should be taken to form a collection of biographies of Darwin and of contemporary literature bearing upon his work, for addition to the library now at Down House. REPORT OF THE COUNCIL, 1937-38 XXiii PROPOSAL FOR THE ESTABLISHMENT OF A DIVISION TO DEAL WITH THE SOCIAL AND INTERNATIONAL RELATIONS OF SCIENCE. The following report, and proposals contained therein, were adopted by the General Committee at its Meeting on August 17, 1938. Ar the present time a strong feeling exists that the social relations of science demand close and objective study. The question has been dealt with recently in the press and elsewhere. At an informal meeting of persons specially interested, it was stated that there is nothing in the constitution of the British Association to prevent the establishment of machinery within that organisation for the purpose desired. A resolution was thereupon addressed from this meeting to the Council of the Association, inviting the Association to establish a special department which would consider the social and international relations of science, by means of enquiry, publication, and the holding of meetings not necessarily confined to the annual meetings of the Association. International relations were specified in this resolution primarily because of the deep interest of the American Association for the Advancement of Science in the subject. Discussion is expected to take place between officers of the two Associations, during the present summer, on the best means for international co-operation. The Council supported the proposal to establish an organisation for these purposes within the Association. They appointed a Committee to formulate a scheme for the working of such an organisation, to be presented to the General Committee at the Cambridge Meeting. It is thought that the organisation should work on lines in some respects different from those of a Section, and should not bear that title. The term Division is therefore recommended. The purpose of the Division would be to further the objective study of the social relations of science. The problems with which it would deal would be concerned with the effects of advances in science on the well-being of the community, and, reciprocally, the effects of social conditions upon advances in science. The Division would be worked by a Committee, nominated annually by the Council and appointed by the General Committee. The Council should have power to appoint additional members of the Committee during the year. The Committee should embody the existing British Science Guild Committee of the Association, inasmuch as the Norman Lockyer, Alexander Pedler, and Radford Mather Lectures, now administered by that Committee, would appropriately come within the purview of the Division. The President of the Association and the General Officers should be ex-officio members of the Committee. A chairman of the Committee should be appointed for a fixed period of office. A fixed proportion of the ordinary members of the Committee should retire annually (as in the case of the Council) and should not be eligible for immediate re-election. XXiv REPORT OF THE COUNCIL, 1937-38 The functions of the Committee would be: (a) To arrange meetings of the Division both at the time and place of the Annual Meetings of the Association, and elsewhere at other times, as invited or otherwise arranged; to appoint speakers, and to accept or reject communications offered to the Division. (6) To furnish material for the information of the public. (c) To co-ordinate work dealing with the social relations of science, both at home and abroad. (d) To be prepared to act in a consultative capacity and to supply information, and to that end to establish relations with organisations and persons engaged in practical administration. (For the furtherance of the above objects, the Committee, immediately upon the establishment of the Division, should issue an announcement | thereof, together with a reasoned statement of its aims, to institutions and other organisations and individuals known or likely to be interested in its work.) (e) To set up sub-committees for executive purposes, or for research, enquiry, or co-ordination. If any such sub-committee should require a grant of money for its work, the Committee should be empowered to apply for such grant to the General Committee or the Council in accord- ance with the usual procedure relating to research committees. (f) To maintain close relations with the Sections of the Association and their Organising Committees. In particular, there may be imagined subjects which two or more Sections might be disposed to recommend to the Division for discussion, in lieu of arranging joint meetings of the Sections. ‘The Committee of the Division, on its part, should be enabled to invite the advice of the sectional organisations on all appropriate questions. The Organising Sectional Committees should be kept regularly informed of the activities of the Division. The Committee should meet regularly throughout the year, at intervals determined by itself, and in particular it should hold a meeting at or near the time of the joint meetings of Organising Sectional Committees in Jan- uary, in order to assure the relations with the Sections referred to above. The Committee should report to the Council as and when necessary, and annually through the Council to the General Committee. PROPOSAL FOR A QUARTERLY REPORT IN PLACE OF THE ANNUAL VOLUME PUBLISHED BY THE ASSOCIATION. The following report was adopted by the General Committee at its Meeting on August 24, 1938, excepting the portion enclosed in [brackets] and dealing with the Journal, which was amended so as to admit of the retention of abstracts, more strictly limited as to length, for use at the Annual Meeting and subsequently for record if necessary. _In November 1937 the Council directed the General Officers to con- sider and report upon the format and printing of the Report of the Association. Subsequently, the Committee which was appointed to REPORT OF THE COUNCIL, 1937-38 XXV formulate a scheme for the new Division referred to above was instructed also to consider and report upon the whole question of publication by the Association. The Committee, after considering various schemes in detail, recommend that as from the year 1939-40 the Annual Volume should be superseded by a Quarterly Report. The annual volume following the Cambridge Meeting would thus be the last of its series. The principal considerations which have led the Committee to make this recommendation are as follows : Quarterly publication should go far to overcome the widespread belief that the British Association is inactive except during its annual meeting. The fact that it now administers the Norman Lockyer, Alexander Pedler, and Radford Mather lectures (which are given at times and places other than those of the annual meetings) points to the desirability of publication at less than annual intervals ; and the establishment of the new Division on the lines recommended would strongly reinforce this argument. Quarterly publication would provide the means of keeping members and the public informed as to the activities of the Association, as an annual volume cannot. Quarterly publication should achieve a wider circulation than the annual volume does for individual communications which call for a wider publicity than they receive by inclusion in an annual volume. It is recommended that the Quarterly should appear in October, January, April and July. The size proposed is royal octavo (approxi- mately 10 x 64 in.). It is suggested that the title The Advancement of Science should be transferred to the Quarterly from the present publica- tion which bears that name and contains the presidential addresses given at the annual meeting. In substitution for the publication of all these addresses together, it is proposed to issue individual addresses separately, at the time of the meeting. The bulk of the material made available from the annual meeting would appear in the October and January numbers. There should, however, be the fullest possible measure of elasticity. This consideration might be expected to apply especially to the reports of research committees, for which delayed publication is sometimes found desirable ; or on the other hand publication in advance of the meeting at which a particular research is to be discussed might be allowed at the discretion of the appropriate Organising Sectional Committee. [It is considered that the Journal of Sectional Transactions, as at present issued at the annual meeting and subsequently incorporated in the Annual Report, is of little value as a permanent record. It is proposed that the present Programme and Timetable should include the programme of each Section separately (as the Journal does now), with abstracts of the briefest possible nature, or none where titles of communications would suffice alone. The transactions of the Sections should be reported in the Quarterly in narrative form, and] so far as finance would allow there should be additional opportunity for publication in extenso or full abstract, and for the reporting of discussions. No changes in the terms of membership subscription are recom- mended ; life members and annual members now entitled to receive the XXVI REPORT OF THE COUNCIL, 1937-38 Annual Report would receive the Quarterly. The price of 3s. 6d. per part is recommended for non-subscribers. The Quarterly should be marketed by arrangement with a publishing firm. The division into quarterly parts would in itself cost little more than the annual volume, even allowing for improvement of the format. Additional matter for publication, however, would be expected from the new Division and from more effective reporting of the work of the Sections. The establishment of the new Division would increase clerical work in the office. On these considerations it has been estimated that the proposals here made might involve the Association in an additional annual ex- penditure of £400-{£500 in a few years’ time; and in this event a temporary draft upon capital would be necessary. It is hoped, however, that such additional expenditure would be offset by increased sales of the Quarterly and reports of Presidential Addresses, as against those of the Annual Volume and the present Advancement of Science, and also by receipts from advertisements in the Quarterly. More- over, the establishment of the new Division and the publication of a Quarterly are both measures which should help to increase the membership of the Association. THE SCIENTIFIC DELEGATION IN INDIA, 1937-38. At the Norwich Meeting of the British Association in 1935, the General Committee of the British Association received Professor J. N. Mukherjee, one of the General Secretaries of the Indian Science Congress Association, who announced that that body would celebrate its jubilee at a meeting in Calcutta in the winter of 1937-38. The Indian Association was founded in 1912-13, and the first meeting took place at Calcutta in the following year. Professor Mukherjee, with Professor S. P. Agharkar, had been appointed to negotiate with the British Association for the purpose of securing the organisation of a.representative scientific delegation to participate in the jubilee meeting. ‘The proposal was new in the sense that the British Association had never before received a definite invitation to co-operate in this manner with a kindred association overseas—that is to say apart from, and in addition to, its own overseas meetings. The General Committee recognised the far-reaching importance of the proposal, and directed the Council to carry on negotiations with the Indian Science Congress Associa- tion. This was done, and the Council were able to report in the following year that the formal invitation of the Indian Association had been received and accepted. The Calcutta Congress was appointed to be held from January 3 to 9, 1938. The Indian Association appointed Professor the Rt. Hon. Lord Rutherford, O.M., F.R.S., to be its President for the jubilee year. He died on October 19, 1937; he had intended to leave England for India on November 26. His loss, deplored by the whole scientific world, was very specially grievous to the delegation and to the Congress. The Indian Association, through the British Association, invited Sir James REPORT OF THE COUNCIL, 1937-38 XXVii e Lahore Pree s 2 ra DIAGRAM OF ROUTE = MUSSOORIE ™., OF DEHRA DUD ES THE SCIENTIFIC DELEGATION IN INDIA Showing places visited by the Delegation (in CAPITALS) and by individual delegates ae d 3 ec ws ae iia pee # DARJEELING toni Tatanagar Jamshedpur Norbade R Eb Tapti'R BOMBAY & Ernakulam Trivandrum Scale of miles ———k—————— =] Colombo 100 50 0 100 200 300 XXVIli REPORT OF THE COUNCIL, 1937-38 Jeans, F.R.S., to take Lord Rutherford’s place in the chair, and fortunately for both bodies he was able to do so at short notice. The Indian Association presented to the British Association lists of scientific representatives whose presence was specially desired. The Council of the British Association appointed a Committee to supervise invitations and arrangements generally, and under the direction of that Committee the General Secretaries issued invitations to persons named as above by the Indian ‘Association, to members of the British Association who had occupied sectional chairs or other high offices, and to certain others whose attendance was desirable in order to assure proper repre- sentation of departments of Science specially appropriate to India. The Indian Association itself issued direct a limited number of invitations, principally to representatives from European countries. ‘The number of invited delegates who accepted invitations was 65, and with the addition of relatives of some of these and certain other members the total number of the visiting party was Ior. The Indian Science Congress Association placed at the disposal of the British Association a sum of £3,125, including a grant from the Govern- ment of India and contributions from other sources. ‘The British Associa- tion collected from institutions, firms, and individuals in Great Britain a sum of £1,356 11s., and made a contribution from its own funds. Grants in aid of travelling expenses were made to invited delegates (with some few exceptions), amounting in total to £4,590. Particulars of the Delegation Account are included in the General Treasurer’s Report for 1937-38. The President travelled as the guest of the Indian Science Congress Association. ‘The same Association appointed at its own charge a tour manager for the official journey of the visiting party in India. Of the party of 101 members, all except eleven either left England by the P. & O. Company’s steamer Cathay on November 26, 1937, or joined her at Marseilles after leaving England at the beginning of December and travelling overland. ‘They reached Bombay early on December 17. Here one of the delegates, Dr. A. B. Rendle, F.R.S., who had been in poor health, was advised not to continue the journey. He remained in hospital at Bombay for a short time, and then returned to England, but died shortly after reaching home (Jan. 12), to the deep regret of his colleagues in the delegation. On landing at Bombay the party was received on the lawn adjacent to Ballard Pier by Mr. V. N. Chandavarkar, Vice-Chancellor of the Univer- sity, Rao Bahadur T. S. Venkataraman, retiring President of the Indian Science Congress Association, Professor J. N. Mukherjee and other representatives. ‘The local reception committee entertained the party to dinner on December 17 at the Willingdon Club, and to luncheon on December 18 at the Taj Mahal Hotel. Opportunities were afforded for visiting departments of the University, St. Xavier’s College, the Royal Insititute of Science, the Grant Medical College, the Haffkine Institute, and other institutions, and also. for seeing something of the many points of interest in the city and its neighbourhood. Lectures or short addresses were given by Sir James Jeans, F.R.S., Prof. F. A. E. Crew (two), Dr. F. W. Aston, F.R.S., Dr. C. S. Myers, C.B.E., F.R.S. (two), Dr. C. G. Darwin, F.R.S., Prof. R. A. Fisher, F.R.S., Mr. H. J. E. Peake, and Prof. H. J. REPORT OF THE COUNCIL, 1937-38 Xxix Fleure, F.R.S.; and Mr. H. M. Hallsworth, C.B.E., had a discussion with advanced students in the Department of Economics in the Univer- sity. Prof. Winifred Cullis, C.B.E., addressed Bombay University Women at the Cama Hospital. It may be stated here, and taken as apply- ing at all points throughout India where general or public lectures were given by delegates, that the numbers and enthusiasm of the audiences were such as to gratify and even astonish the visitors. Broadcasts were given from the Bombay station of All-India Radio by Prof. Winifred Cullis, C.B.E., and Prof. F. A. E. Crew. The party left Bombay in the afternoon of December 18, in the special train which was to be their headquarters during the tour through northern India until January 2, and again for those of them who joined the southern tour after the Congress in Calcutta. The train consisted of the Punjab Limited rolling-stock of the Great Indian Peninsula Railway, and for the outward tour included seven corridor coaches with compartments affording very comfortable living and sleeping accommodation for two persons each, two dining cars, a brake, a servants’ car, and a commissariat car. The travel arrangements were made by the Indian Science Congress Associa- tion in collaboration with the railway companies concerned and with Messrs. Thos. Cook & Son as agents. Mr. W. D. West, one of the General Secretaries of the Indian Association, had principally dealt with the details of organisation of the tours in advance, and Prof. J. N. Mukherjee, the other General Secretary, accompanied the tour preceding the Congress, and dealt with all the arrangements therefor excepting those at Agra and Dehra Dun and those of the geologists’ visit to Dhanbad, etc. In the morning of December 19 the party reached Hyderabad, the capital of the Deccan State of that name, and during their sojourn within its frontiers they were guests of the State in respect not only of entertainment, but also of accommodation and travel. They visited the site of the Osmania University, which was established in 1918, and were shown the buildings and departments already erected and in operation. The medical college and Osmania hospital, the museum, the Nizamiah Observatory, and the Cottage Industries Institute were seen by individual members. Sir James Jeans, F.R.S., addressed the University staff and students, and various members of the party were enabled to meet professors and students in the departments in which they were specially interested, and to discuss their work. The whole party was entertained to lunch in the University hostel. Afterwards Golconda, an immense hill-fort and the capital of the Kutb Shahi Kingdom of the sixteenth and seventeenth centuries, was visited, and also tombs of the kings of this dynasty. Sir Arthur Eddington, F.R.S., gave a lecture in the Town Hall, and a banquet was held in the Address Hall of the University. The party left at night for Aurangabad in a narrow-gauge train provided by the State, and next day (December 20) visited the rock-hewn temples at Ellora, which range in dates from the third to the ninth century a.D., and in which the Buddhist, Brahmanic, and Jain religions are represented. The hill-fortress of Daulatabad, founded probably in the twelfth century, and other historic sites were also seen. On December 21 the party was taken by road to Ajanta, the site of another great series of rock-temples, where the architecture, sculpture, XXX REPORT OF THE COUNCIL, 1937-38 and painting ‘ represent every stage of Buddhist art from the first century B.C. to the middle of the seventh century a.p.’1_ From Ajanta the party proceeded by road to Jalgaon, where the broad-gauge train was rejoined at night. rie morning of December 22 a halt was made at Sanchi, in Bhopal State, where the Buddhist stupas and other remains, dating from the third century B.c. to the twelfth century A.D., were visited. In the evening the train arrived at Agra. Some of the delegates visited the Taj Mahal the same night, and it was here that Dr. W. W. Vaughan met with the lamentable accident which resulted in his death. In the darkness he fell from a terrace which is unprotected by any parapet. One of his legs was broken, and after a long illness he died in the Thomason Hospital at Agra on February 4, 1938, to the keen distress of all his colleagues in the delegation. On December 23 the Fort and the Taj Mahal, superb monuments of the Mogul Emperors Akbar, Shah Jahan, and Aurangzeb (1556-1707), were visited, and some of the party were able to see the fort of Fatehpur Sikri and also the Latitude Variation Observatory of the Survey of India, and the Upper Air Observatory of the Meteorological Department. Sir James Jeans, F.R.S., gave an address to students at the University. The main party left Agra in the evening of December 23, and arrived at Delhi in the morning of December 24. Some members, however, diverged in order to visit Aligarh, where, at the University, short addresses were given by Prof. Ernest Barker, Sir Arthur Eddington, F.R.S., Prof. W. T. Gordon, Dr. W. G. Ogg, and Dr. Dudley Stamp. At Delhi on Christmas Eve and Christmas Day the great modern group of Government buildings—the Viceroy’s House, the Secretariat, and the Council House—and the new Imperial Institute of Agricultural Research were visited, as well as many historical monuments, such as the fort, the palace, and Juma Masjid (mosque) of Shah Jahan (c. 1640), the ruined old fort of the fifteenth century, the mosque of Sher Shah, and the twelfth-century Tower of Victory known as the Kutb Minar, with its adjacent Jain and Hindu temples and mosque and the famous iron pillar to which is assigned an age of fifteen centuries or more. The Government of India entertained the party to luncheon on Christmas Eve, and on Christmas Day most generous entertainment was extended to individual members by many residents, Indian and British, in New Delhi. Broadcasts were given on Christmas Eve by Sir James Jeans, F.R.S., and Dr. O. J. R. Howarth. Leaving Delhi on Christmas night, the party reached Dehra Dun in the morning of December 26. Here members visited the Forest Research Institute and the Geodetic Branch of the Survey of India. The Forestry Research Institute, established in 1906, occupies an estate of 1,400 acres, and its fine buildings, besides administrative and residential quarters, include a chemical branch, insectary, saw mill, pulp and paper plant, wood workshops, and timber testing, seasoning and preservation labora- tories, while there are also an arboretum and botanical and experimental ? This quotation, and much of the information throughout this report, are taken with grateful acknowledgment from the guide-book specially prepared for the delegation by the Indian Science Congress Association. REPORT OF THE COUNCIL, 1937-38 Xxx gardens. The work of the Geodetic Branch includes, among other activities, precise levelling for the determination of heights, tidal pre- dictions and the publication of tide tables for ports between Suez and Singapore, the magnetic survey, astronomical observations for the determination of latitude, longitude, and time, seismographical and meteorological observations, and topographical survey and map reproduc- tions. Most of the party found time to drive up to Mussoorie (6,500 feet), from which the view of Himalayan snow-mountains is restricted, but that over the foothills and the plains to the south is of impressive extent. The party left Dehra Dun late on December 26, and reached Benares in the afternoon of December 27. Sir Arthur Eddington, F.R.S., visited Allahabad, and presided over a colloquium on astrophysics. On arrival at Benares the party was conveyed to Sarnath, where, about five centuries before Christ, Buddha first preached after his enlightenment, and where Asoka set up the great Dhamekh stupa in the third century B.c., and a column of which broken remains are seen on the ground, while the richly sculptured capital is in the adjacent museum. On December 28 the party viewed from boats the famous river-frontage of Benares with its temples, ghats, and steps. Afterwards members were entertained in the Benares Hindu University, and attended its twentieth Convocation, at which, among others, the following delegates received honorary degrees: Sir James Jeans, F.R.S., Sir Arthur Eddington, F.RS., ir. F. W. Aston, F.R.S., Prof. E. C. C. Baly, C.B.E., F.R.S., Prof. V. H. Blackman, F.R.S., Prof. C. G. Jung, and Prof. F. A.E. Crew. Sir _ James Jeans addressed the Convocation, and lectures or short addresses to students were subsequently given by Dr. F. W. Aston, F.R.S., Prof. mc. C. Baly, C.BE., F.RS., Prof. Ernest Barker, Prof. V. H. Blackman, F.R.S., Prof. F. A. E. Crew, Sir Arthur Eddington, F.R.S., and Prof. C. G. Jung. From Benares, which was quitted on the night of December 28, the special train proceeded to Calcutta, which was reached in the afternoon of December 29. It crossed the great Chinsurah bridge over the Hooghly above the city, in order to enter Sealdah station, where it remained for little more than an hour, and then proceeded through the night to Siliguri, taking the great majority of the members for a visit to Darjeeling. It will be apparent from the preceding narrative that much of the railway-travelling was done at night, but sufficient took place in daylight to afford, together with the long road-journeys in Hyderabad and shorter drives elsewhere, at least a cursory view of the main geographical regions of central and northern India which were traversed. After the departure from Bombay in the late afternoon, there remained just sufficient light to reveal the transition from the flat lowland of the Konkan country to the flat-topped hills of the Western Ghats with their isolated pinnacles and bold escarpments of basaltic lavas, deeply eroded. The plateau of peninsular India, wherever it was traversed, whether in Hyderabad or during the tour after the Congress, farther south, was seen in dry condi- tions ; occasionally even a semi-desert type of vegetation was apparent. If the scenery of the plateau left a general sense of monotony, it was at any rate possible to distinguish some of its different physical character- istics. The vast tracts of red laterite soil gave a peculiar impression of XXXil REPORT OF THE COUNCIL, 1937-38 aridity, by contrast, especially, with the alternating areas of black cotton soil. Again, during the traverse of Hyderabad State it was possible to observe the distinctions of form between the volcanic region of the Deccan trap and the undulating plains and rounded hills of the Archaean crystal- line rocks with their irregularly weathered tors of granite boulders, One of the escarpments of the trap country was finely seen on the descent to the gorge in which the caves of Ajanta are excavated, and here, as well as at Ellora and in the moat and scarp of Daulatabad fort, the manner in which the basalt on the one hand had lent itself to artificial working, and on the other its resistance to the influences of weathering, was wonderful to see. ‘The area of Pre-Cambrian sandstones which ‘ have furnished a great wealth of building stone to the architects of ancient India and stimulated their art’ were crossed in the vicinity of Sanchi, and the rough and rather barren quartzites and metamorphic rocks of the Delhi system offered a further contrast both to the Sanchi country and to the rich alluvial plains of the Gangetic rivers, which were traversed northward towards Dehra Dun and eastward to Calcutta. ‘ The plains rise in gentle undulations away from the river banks, and for miles there is an unbroken succession of fields, orchards, and mango groves, surround- ing clusters of mud villages.’ The scenery thus described was un- interrupted during December 29, save where the Rajmahal hills in Bihar rise as outliers of the Chota Nagpur plateaux to the south. This last district was visited by a small geological party, which left the special train at Kodarma on December 29, and proceeding by way of Ranchi, Gua, Jamshedpur, and Dhanbad, arrived in Calcutta early on January 3. At two points the route of the special train traversed the rich sub- montane tracts bordering the plains on the north-east, and afforded views of the impressive approaches to the wall-like foothills of the Himalayan mountain-system. ‘The first of these occasions was at Dehra Dun as already indicated ; the second at Siliguri on December 30. Here the railway was left for the ascent by road to Darjeeling, where, at a height of some 7,000 feet above sea-level, the party had the extreme good fortune to enjoy two-and-a-half days (December 30-January 1) of perfect weather, in unclouded view of the Himalayan range which culminates in Kangchenjunga (28,146 feet). The party returned to Calcutta in the morning of January 2. From Calcutta the President, Sir James Jeans, F.R.S., conveyed thanks on behalf of the party to the following gentlemen who had been instru- mental in arranging for the hospitality and facilities afforded at the various places visited :— Bombay : Rao Bahadur V. N. Chandavarkar, Vice-Chancellor of the University. Hyderabad : 'The Rt. Hon. Sir Akbar Hydari, President of the Executive Council and Chancellor of the Osmania University; the Hon. Nawab Mehdi Yar Jung, political and education member and Vice-Chancellor of the University ; Prof. Kasi Mohamed Husain, Pro-Vice-Chancellor of the University. Agra: Mr. Zafar Hasan, Superintendent, Archeological Survey of India, Northern Circle ; Mr. G. Chatterjee, Meteorological Office ; Prof. K. C. Mehta, Department of Botany, Agra University. REPORT OF THE COUNCIL, 1937-38 XXXIil Delhi: Sir Girja Sunkar Bagpai; the Hon. Sir Shah Sulaiman ; Mr. Lala Sri Ram. Dehra Dun: Mr. L. Mason, C.I.E., Inspector-General of Forests ; Col. C. M. Thompson, Director of the Geodetic Branch, Survey of India. Benares : Pundit M.M. Malaviya, Vice-Chancellor of the Benares Hindu University ; Raja Juala Prasad, Pro-Vice-Chancellor of the University. The Silver Jubilee Session of the Indian Science Congress Association was opened by H.E. the Viceroy of India (the Marquess of Linlithgow), in the University College of Science, Calcutta, on January 3, 1938. Sir James Jeans, F.R.S., after his own short prefatory address, com- municated to the Congress the presidential address which had been prepared by Lord Rutherford. The reception room, offices, and section meeting rooms of the Congress were in the Presidency College, the University Buildings, the All-India Institute of Hygiene and Public Health, and the School of Tropical Medicine. The transactions of the Congress were continued daily until January 9, with the exception of January 6, a day devoted to excursions. The transactions are fully reported by the Indian Science Congress Association, but it may be mentioned here that occasion was taken during the week to hold also the annual meetings of the National Institute of Sciences of India, the Indian Chemical Society, the Indian Physical Society, the Indian Section of the Institute of Chemistry of Great Britain and Ireland, the Indian Botanical Society, the Society of Biological Chemists of India, the Indian Psychological Association, the Indian Society of Soil Science, the Physiological Society of India, and the Indian Anthropological Institute. Diplomas of honorary Silver Jubilee membership were presented to Sir James Jeans, F.R.S., Dr. F. W. Aston, F.R.S., Prof. L. F. de Beaufort, Prof. A. H. R. Buller, F.R.S., Prof. Sir Arthur Eddington, F.R.S., Sir Frederick Hobday, C.M.G., Prof. C. G. Jung, and Prof. J. L. Simonsen, F.R.S., of the delegation, and also to Sir Venkata Raman, F.R.S., Sir Prafulla Ray, Prof. M. N. Saha, F.R.S., and Sir M. Visbesbaraya. Public lectures were given by Sir James Jeans, F.R.S., and other members of the delegation, including Dr. F. W. Aston, F.R.S., Prof. Ernest Barker (two), Prof. F. A. E. Crew, Dr. C. G. Darwin, F.R.S., Prof. Sir Arthur Eddington, F.R.S., Prof. H. J. Fleure, F.R.S., and Dr. J. A. Venn. Among other lectures given by the delegates to various bodies in Calcutta were the following. The Indian Association for the Cultivation of Science conferred upon Sir James Jeans, F.R.S., and Dr. F. W. Aston, F.R.S., the Joy Kissen Mookerjee Medal for 1937 and 1938 respectively, and each delivered an address to this Association on the occasion of the award of the medals. The same Association heard three lectures by Prof. J. E. Lennard-Jones, F.R.S., as Coochbehar Professor, and three by Sir Arthur Hill, K.C.M.G., F.R.S., as Ripon Professor ; while Dr. A. E. H. Tutton, F.R.S., devoted much time to discussion in the laboratory of the Association. Sir Henry Tizard, K.C.B., F.R.S., and Prof. J. L. Simonsen, F.R.S., addressed the Institute of Chemists ; Sir Arthur Eddington, F.R.S., the Indian Physical Society and also the Rotary Club ; Prof. F. A. E. Crew the local branch of the Indian Medical Association. ‘The Institution of Engineers received XXXIV REPORT OF THE COUNCIL, 1937-38 lectures by Prof. R. V. Southwell, F.R.S., and Prof. G. W. O. Howe ; and Prof. Howe also addressed the Association of Engineers. Four lectures in the University and one to industrialists were given by Dr. C. S. Myers, C.B.E., F.R.S., and two in the College of Science by Prof. C. G. Jung. Prof. Winifred Cullis, C.B.E., and Dr. E. P. Poulton addressed the Physiological Society of India, Dr. Poulton the Indian Medical Association, and Prof. R. Ruggles Gates, F.R.S., the Botanical Society of Bengal and the Bose Institute. Prof. P. G. H. Boswell, F.R.S., addressed University students. Broadcasts were given by Dr. W. G. Ogg, Sir Arthur Hill, K.C.M.G., F.R.S., Prof. P. G. H. Boswell, F.R.S., Dr. C. S. Myers, C.B.E., F.R.S., Sir Arthur Eddington, F.R.S., and Prof. H. J. Fleure. F.R.S. Sir James Jeans, Sir Arthur Hill, and other delegates took part in the celebration of the 150th an- niversary of the Botanical Gardens on January 6. A number of the delegates attended a Vice-regal garden party at Belvidere on January 4, and H.E. the Governor of Bengal (Lord Brabourne) and Lady Brabourne gave a garden party for the Congress on January 7, which was followed at, Government House by a special Convocation of the University of Calcutta, at which honorary degrees were conferred upon Sir James Jeans, F.R.S., Dr. F. W. Aston, F.R.S., Prof. Ernest Barker, Sir Arthur Eddington, F.R.S., Prof. A. H. R. Buller, F.R.S., Prof. R. A. Fisher, F.R.S., Prof. C. G. Jung, Dr. C. S. Myers, C.B.E., F.R.S., and Prof. W. Straub. The Corporation of the City of Calcutta gave a civic reception on January 4; a Science Congress dinner was held on January 8; the University of Calcutta gave a farewell party in the afternoon of January 9, and the hospitality of other official and non-official bodies and private residents was lavish and extensive. The Indian Science Congress Association, at the conclusion of the Congress, embodied their thanks to all concerned in a series of resolutions, and on behalf of the delegation Sir James Jeans, F.R.S., issued the following message to the Press : ‘At the moment of leaving Calcutta, the visiting scientific delegation tender their most sincere thanks to all the kind hosts who have helped to make their stay in Calcutta so enjoyable. ‘The Scientific Congress which we have been privileged to attend has impressed us all with its extraordinary vitality, with the widespread and generous attention accorded to our own contributions, and with the keen public interest which the transactions of the meeting have aroused. The huge audiences at the public lectures have been specially gratifying. “I must reiterate our appreciation of the compliment paid by the Indian Science Congress Association to the British Association for the Advancement of Science in inviting its co-operation in the arrangement of the delegation ; that invitation has forged a powerful new bond-between Indian and British Science, to the great advantage of both, and we all hope that the effects of that bond may prove wider even than the bounds of science. “We offer our thanks to the Indian Science Congress Association, to its kindred scientific institutions, to the many organisations which have contributed to the success of the Congress, to the City and University of - Calcutta and to the province of Bengal. “The women of the party owe special gratitude to the ladies, resident in Calcutta, who have afforded them such ample opportunities for learning of the manifold interests of the City.’ REPORT OF THE COUNCIL, 1937-38 XXXV On the conclusion of the Congress some of the delegates proceeded to various points in India in pursuance of personal scientific interests and engagements. A party of over fifty of the visitors, however, left Calcutta for the south in the special train on the night of January 9g. On the following day they saw something of the picturesque scenery of the maritime plain bordering the Eastern Ghats, and they reached Madras in the forenoon of January 11. Here they were entertained by the University of Madras at a luncheon, visited the museum, the aquarium, and other points of interest, and on the invitation of the Sheriff of Madras attended a garden party arranged by the city in honour of the Viceroy. The thanks of the party were subsequently conveyed by the President to the Vice-Chancellor of the University and to the Sheriff of the city. Lectures were given by Prof. Ernest Barker, by Prof. F. J. M. Stratton at the Christian College, Tambaram, and by Prof. J. L. Simonsen, F.R.S., at the Presidency College Chemical Society. The special train left Madras at night, and the next morning (January 12) the party changed at Bangalore into a narrow-gauge train for Mysore City. At Bangalore and Mysore, and for the intervening journey, they were the guests of the State of Mysore. At Mysore City they were accommodated in Government House and in a camp (a term of more elaborate connotation in India than at home). Lectures were given by Sir James Jeans, F.R.S., Dr. F. W. Aston, F.R.S., Prof. Ernest Barker, Sir Arthur Eddington, F.R.S., and Prof. C. E. Spearman, F.R.S. The Maharaja’s palace, the University, the Technical Institute, the Zoological Gardens, and various institutions were visited by members, and after nightfall they viewed with wonder the illuminated fountains at the great dam on the river Cauvery, and the city, brilliantly lit up, from Chamundi Hill. On the morning of January 13 the fort at Seringapatam and the tombs of Hyder Ali and Tippu Sultan were inspected, and the party entrained for Banga- lore. Here again a number of institutions were visited, including the Indian Institute of Science and the College of Science. Sir James Jeans, F.R.S., addressed students at both the college and the institution, and the following also spoke: Dr. F. W. Aston, F.R.S., Prof. Ernest Barker, Prof. P. G. H. Boswell, F.R.S., Prof. F. A. E. Crew, Dr. C. G. Darwin, F.R.S., Prof. W. T. Gordon, and Prof. J. L. Simonsen, F.R.S. The thanks of the members were subsequently conveyed by the President to His Highness the Maharaja of Mysore, to Sir Mirza M. Ismail, Dewan Sahib of Mysore, and to Sir Charles Todhunter, K.C.S.I., private secretary to the Maharaja. The party entrained at Bangalore on the night of January 13, and travelled direct to Bombay, where on January 15 they embarked on the S.S. Strathaird for the voyage home. Before doing so, Prof. Ernest Barker and Dr. R. N. Salaman, F.R.S., gave lectures, and Prof. Winifred Cullis, C.B.E., addressed the Association of British Women Graduates in India. The members who took both the tours described above, before and after the meeting, travelled close upon six thousand miles in India. The weather was beautiful throughout the visit, except for a storm of short duration at Calcutta in the afternoon of January 9. b2 XXXVI REPORT OF THE COUNCIL, 1937-38 Before leaving Bombay, the President, on behalf of the Delegation, issued the following message through the Press :— ‘In taking leave of India, we of the Scientific Delegation desire again to express our thanks for the overwhelming kindness with which we have been received in all parts. A month ago we landed here, eagerly expectant of what we were to see and learn. We are now returning home after a journey of more than five thousand miles through the country, during which we have been able to visit many monuments of ancient civilisations, and have admired the care with which the legacies of the past are preserved. But more of our time has been devoted to the present, and we have realised to the full the scientific and cultural developments which are in progress both in the universities and in the field of practical applications throughout the country. : ‘Nothing has more deeply impressed us than the interest shown in Science by the community at large and the eagerness with which students are following and practising the most recent advances in research. India has achieved self-sufficiency in many directions, but there is an acknowledged need for influences which shall further bind together her varied races. Her achievements in the realm of thought and her progress in the develop- ments of industry lead us to hope that Science, which transcends all national and racial frontiers, may provide such a unifying influence. Long may Science continue to help in maintaining and advancing the position of India in the community of civilised nations.’ The activities of delegates were not confined to Calcutta and to the places visited during the tours. ‘Thus, Prof. R. A. Fisher, F.R.S., following from Bombay an itinerary independently of the main party, lectured at Hyderabad (twice), Lucknow (twice), Aligarh, and Benares, and again at Bombay on his homeward journey, besides giving a course at Calcutta University. Before the Congress at Calcutta, Sir Henry Tizard, K.C.B., F.R.S., visited the Tata Iron & Steel Works at Jam- shedpur, and lectured there. Sir Frederick Hobday addressed students in the Indian Veterinary Colleges at Bombay, Calcutta, Lahore, Madras, and Patna. At Madras, at times other than that of the visit described above, Prof. C. B. Fawcett gave lectures in the University and to the Madras Geographical Association ; Prof. F. E. Fritsch, F.R.S., gave four post-graduate lectures, and Lt.-Col. R. B. S. Sewell, C.I.E., F.R.S., three lectures in the University ; and Prof. R. Ruggles Gates, F.R.S., also lectured there. Prof. C. B. Fawcett, Prof. R. Ruggles Gates, F.R.S., Prof. C. G. Jung, and Prof. W. M. Tattersall visited and spoke at the University of Travancore in Trivandrum; Sir Arthur Hill, K.C.M.G., F.R.S., and Dr. E. M. Crowther, the Agricultural College and Research Institute in Coimbatore ; Prof. J. E. Lennard-Jones, F.R.S., the University of Lahore; Mr. J. McFarlane that of Patna; Dr. C. S. Myers, C.B.E., F.R.S., that of Allahabad. Prof. R. Ruggles Gates, in addition to lectures already mentioned, spoke at Bombay (Royal Institute of Science), Banga- lore (Central College), Coimbatore (Association of Economic Biologists), and Ernakulam (University College). Prof. H. H. Read fectured to the Indian School of Mines Scientific Society at Dhanbad. Prof. A. G. Ogilvie lectured to the Bombay Geographical Association, and informally addressed students at Wilson College in that city and at Hislop College, Nagpur. Prof. P. A. Buxton, visiting Ceylon, addressed the Colombo REPORT OF THE COUNCIL, 1937-38 XXXVil branch of the British Medical Association. Dr. W. G. Ogg advised the State authorities in Hyderabad on the Tungabadhra irrigation project, and other delegates were called into conference at many points for advice on matters connected with their special interests. After the return of the delegation to England, the Council adopted the following resolution :— The Council of the British Association have learned with gratification of the complete success that attended the visit of the Scientific Delegation to India, the members of which, through the invitation of the Indian Science Congress Association, were enabled to co-operate in its Jubilee Meeting in Calcutta, to visit many places of scientific and historical interest in India, to become acquainted with the work of many universities and other institutions, and to make or renew personal contacts with large numbers of Indian scientific workers and leaders of thought. ‘The Council are glad to hear of the opinion, widely expressed in India, that much good would result from the visit, and this belief the Council heartily reciprocate. The Council desire to endorse the expressions of gratitude which have already been transmitted, on behalf of the Delegation, to the Government of India, to all other participant authorities and individuals, and very specially to the executive of the Indian Science Congress Association. The Executive Committee of the Indian Science Congress Association at its meeting on September 20, 1938, returned the following reply to the above resolution :— The Executive Committee of the Indian Science Congress Association have received with sincere pleasure and gratification the resolution of the Council of the British Association stating that the visit of their Scientific Delegation to India has been a complete success and has enabled the Members of the Delegation to make or renew personal contacts with Indian scientific workers and leaders of thought. They share with the Council of the British Association the belief that much good would result from the visit. "The Executive Committee very much appreciate the friendly feelings expressed by the Council of the British Association on behalf of the Delegation to the authorities and individuals who contributed towards the success of the Silver Jubilee Session and expressed in par- ticular their appreciation of the reference to the Executive Committee of the Indian Science Congress Association. The Executive Committee convey to the Council of the British Association their warmest appreciation of the manner in which the British Association have responded to their invitation to join the Indian Science Congress Association in joint session to celebrate the Silver Jubilee Session. GENERAL TREASURER’S ACCOUNT Balance Sheet, XXXVili Corresponding LIABILITIES irae GENERAL PURPOSES :— 1937. Sundry Creditors . : : 2 £ os. d. Hon. Sir Charles Parsons’ gift (£10,000) and legacy (£2,000) The late Sir Alfred Ewing’s legacy British Science Guild : Capital Fund Bequest of Jaakoff Prelooker . = Yarrow Fund As per last Account £4,744 16 1 Less Transferred to In- come and Expendi- ture Account under terms of the gift . 383 9 8 Life and Corporate Compositions As per last Account 3,138 12 2 Add Received gunng Wear) ov. . iS) A730 3014 92 Less Transferred to In- come and Expendi- ture Account ° 55 10 Contingency Fund ““ A” As per last Account 1,940 17 1 Add Amount trans- ferred from Income and Expenditure Account 3 59 2 il Contingency Fund “B’”’ Amount transferred from Income and Expenditure Account Accumulated Fund As per last Account 16,488 9 0 Less'‘Transfer to Indian Science Congress Delegation Fund . 21615 6 42,702 0 11 | SPECIAL PURPOSES :— Caird Fund Balance at Ist April, 1937 Less Excess of Expenditure over In- come for the year . 9,791 15 10 Mathematical Tables Fund Balance at Ist April, 1937 . Receipts from Sales . Less Payment to Cambridge Uni- versity Press, re Vol. VI - 144 6 3 Cunningham Bequest Fund Balance at Ist April, 1937 . Add Excess of Income over Expendi- ture for the year 1,395 9 10 fe ts: red: 785 2 9 12,000 0 0 500 0 0 3,431 9 1 10 0 O 4,361 6 5 3,258 19 2 2,000 0 0 29 16 3 16,271 13 6 9,791 15 10 41 1 144 6 3 29° 294 173i gu) ad 150 0 0 1,395 9 10 12 Carried forward Leese de 42,648 7 2 9,750 14 2 1,407 18 6 53,830 8 5 GENERAL TREASURER’S ACCOUNT xxxix 31st March, 1938 Corresponding ASSETS igure 31st March, eS a Eis rd, 1937. GENERAL PURPOSES :— Investments as scheduled with Income and Expenditure Account, No.1 . 41,979 7 7 Sundry debtors and Borns in ad- vance . i % 528 10 9 Cash at bank . 3 ; . ‘ 96 9 7 ‘ Cash in hand . : : $ ‘ 43 19 42,702 0 11 ———_ 42,648 7 2 SPECIAL PURPOSES :— Caird Fund Account Investments (see Income and Ex- penditure Account, No. 2) . 3 O,582el6~ 3 Cash at bank : : : - Like be 0 9,791 15 10 OU ere Mathematical Tables Fund (ae Cash at bank ; : 23. Sid Sundry debtors . ce - - -— 144 6 3 ae 23 8 7 Cunningham Bequest Fund Account Investments (see Income and Ex- penditure Account, No. a 5 a, 1300 baa Cash at bank . : - 102 11 1,395 9 10 Se Ae 186 & DO Carried forward . 7 953,930 8 5 xl GENERAL TREASURER’S ACCOUNT Balance Sheet, nee penaing LIABILITIES (continued) 3ist March, Lees. de 9G Tai Tee 1937. Brought forward = - 53,830 8 5 £ 8. d.| Toronto University Presentation Fund Capital . 0 5 : 178 11 4 Revenue . : : A : 4 7 6 182 18 10 182 18 10 Bernard Hobson Fund Capital . 1,000 0 0 Revenue—Balance per last Account . oe ooorel=.3 Less Excess of Expendi- ture over Income for the year SAPs —__. SHUNT pe 1,058 1 3 tre Ae? 1,031 7 9 Leicester and Leicestershire Fund, 1933 Capital - - 1,000 0 0 Revenue— Balance per last Account . 42 2 6 Less Excess of Expendi- ture over Income for the year . = “ 15 10 — 41 6 8 1,042 2 6 ok APSE 1,041 6 8 Herbert Spencer Bequest Fund “ 1107 9 0 Less Excess of Expenditure over Income for year : y - 384 4 6 1,107 9 O 723).4'i6 Norwich Fund, 1935 Balance per last Account . : 105° 30, 0 Less Expenditure for year . : 50 18 0 105 0 0 Amora Radford Mather Lecture Fund Capital . : 2 250: 00 Sundry Creditor . < : : 30 AG 250 0 0 ——<———— 289 4 6 Down House Endowment Fund : -. 20,000 0 O Sundry Creditors and Credit Balances : 5 < : LZ M2576 Suspense Account BalanceperlastAccount 80 13 9 Less Excess of Expendi- ture over Income for the year. - emo hihi a 30 12 7 20,093 5 5 pe 20,043 5 1 NOTE,—There are contingent Liabilities in respect of grants voted to Research Committees at Nottingham and by Council in 1937 but not claimed at 31st March, 1938, amounting to £416 17s. 9d. 77,872 9 10 £77,195 17 9 I have examined the foregoing Account with the Books and Vouchers and certify” and the Investments, and the Bank have certified to me that they hold the Approved. EZER ret) Auditors. R. S. WHIPPLE OE —————————— rl CC ee —— EEE oe i GENERAL TREASURER’S ACCOUNT xli 31st March, 1938 (continued) See roncing ASSETS (continued) 31st March, eae nS aC if ism, fda ak ‘ Brought forward : : : 53,830 8 5 $s. Toronto University Presentation Fund Account Investments (see Income and Ex- penditure Account, No. 4) . é 178 11 4 Cash at bank - : ; ‘A 400 6 182 18 10 a 182 18 10 Bernard Hobson Fund Account Investments (see Income and Ex- penditure Account, No. 5) = 1,000) 505 3G Cash at bank . : Z : Sy e7ee9 1,058 1 3 oe ees) 103i 7 9 Leicester and Leicestershire Fund, 1933 Account Investments (see Income and Ex- penditure Account, No. 6) 15000" 00 Cash at bank - $ c 3 41 6 1,042 2 6 don oe 1,041 6 8 Herbert Spencer Bequest Fund Account Investments (see Income and Ex- penditure nia image No. 7) 2 123° 4. 16 Cash atbank . = é ae 1,107 9 O ae TOBe CAG Norwich Fund, 1935 Account (Income and Expenditure Account, 105 0 0 No.8) . a < 3 3 54552) 10 Cash at bank ; —- Radford Mather Lecture Fund Micaat Investments (see Income and Ex- penditure Account, No. 9) . 250 0; 40 Add Excess of Expenditure over Income for the year . r 5 39 4 6 250 0 0 —_——_—— 289 4 6 Down House Account Endowment Fund Investments (see Income and Expenditure Account, No. 10). 5 : 2 . 20,000 0 0 Cash at bank : 4 - 3113 4 Cash in hand - F -- Sundry debtors and payments in advance . Hil >9 20,093 5 5 ——— 20,043 5 1 77,872 9 10 £77,195 17 9 the same to be correct. I have also verified the Balance at the Bankers Deeds of Down House. W. B. Keen, Chartered Accountant. 23 Queen Victoria St., London, E.C. 4. and June, 1938. GENERAL TREASURER’S ACCOUNT xii *9f61 ‘HOUVIN IsIef GyaNa AVaAA AHL YOHX SLNNOOOV FAAYNLIGNAdXA GNV AWOONI 0s I6 : ‘ s a * sloquisur yuopnyg ‘* | 0 OL 68 0 O° +8 * Anuejunoosy pue upny ‘ | 0 #1 g¢ O SIOTT * *° * * St9ROEL eqeseysuery, ‘| 0 9 9sT OI 91 9S ‘+ + srouoniqryxg “* | 6 £1 79 9 ZI zEs . 2 qaoday yim ‘sroquisuitenuuy ‘** | 9 OL 69% Il I 6UI . * sosuodxe Sumoavry, ** | 2 & IE Oo. eliat + ATUO Suysay~J IOJ staquiour jenuuy ‘* | o ¢ ees'T OI LI €Fl < ‘ * saBeysog “ | OF FI 8ST 0 0 +L : : siaquiay| Iepnsoy yenuuy pio Ag | 0 0 a 00 J : e : s qyuoy “ | 00T pe F peg OI SI L8 : ‘ * — Arouonwig “* | 6 sr 9Z 0 6 OF Jomog pue sunysry ‘yeozy OF, | OL or se “L861 ack Sf paces AWOONI Taam AUNLIGNaAdXa Surpuodse1109 "PS “Sg BSI F ‘puey ur pue yueq ye yse_D Ee ee (P6 ‘Sh beeHHFL L GLO IHF (‘por ‘spr Fog PEF ‘LE/E[1E |r er 196'TF iSc/ehigd?. Cu(Ag)I], as shown by their molecular weights and, are systematically named by the authors as ¢etrakis[iodotrialkylphosphine (or arsine) copper (or silver)]. Crystallographic investigations strikingly revealed the existence of these four-fold macro molecules in the solid state and the tetrahedral configurations of the 4-covalent cuprous and argentous silver complexes and, in addition, and for the first time, the aa ee eS B.—CHEMISTRY 37 tetrahedral configuration of 3-covalent iodine. The trialkylphosphine and trialkylarsine derivatives of aurous chloride and aurous iodide have, however, the general molecular formula R,P(As)—>AuCl(I) and the mole- cule has probably a linear configuration. ‘The trialkylphosphine-gold compounds are remarkably stable and can be distilled at low pressures without decomposition. On the other hand, Mann and his co-workers have suggested that in the non-electrolytes, Et,P(NH ;),AuCl and (EtO),P(NH;),AuCl prepared by Levi-Malvano (1908), the aurous gold atom is 4-covalent, acquiring seven electrons and having an Effective Atomic Number of 86, the atomic weight of radon, the next inert gas. If this is the case these compounds are unique in the chemistry of gold ; but it would appear that the determination of co-ordination numbers from ammonia derivatives is not always satisfactory. Aurous com- pounds having the compositions NH,AuCl, (NH;),AuCl, (NH;),AuCl and even (NH;),;,AuCl have been described. Of these monoammino- chlorogold and diamminoaurous chloride having the respective con- stitutions : H,N-—-Au—Cl and [H,N—Au<-NH,]Cl are by far the most stable and in these compounds the aurous gold atom is 2-covalent. The well-authenticated salts (NH;),HCl (Joannis 1902), (NH,;),HBr (Bakhuis-Roozeboom 1885) and (NH;)4HNO, (Kuriloff 1898) may be compared with Levi-Malvano’s compounds and with triamminochlorogold. It would appear more doubtful that such com- pounds afford evidence of the 4-covalency of hydrogen or aurous gold rather than that they indicate the existence of chain formation of ammonia molecules with links of co-ordinated hydrogen. If, however, by using a more suitable co-ordinating compound than ammonia, it could be established definitely that aurous gold may be 4-covalent as well as 2- covalent, it would be interesting to determine whether such quadri- covalent aurous compounds like the quadricovalent cuprous and argentous compounds have a tetrahedral distribution of valencies. In this con- nexion, the use of thioacetamide by Cox, Wardlaw and Webster (1936) for the successful preparation of tetrakisthioacetamidocuprous and tetrakisthioacetamidoargentous chlorides : CH, | C=S }J—Cu(Ag) |Cl INE Zig does not appear to give an analogous aurous gold compound. The only aurous derivative of thioacetamide which Dr. F. H. Brain and I have been able to isolate is the somewhat unstable bdzsthioacetamidoaurous bromide (1937) : CH, CH, | C=S—Au Au—R h R was prepared from di-n-propylmonobromogold (R = Pr*) and no ana- logous compound was obtained from diethylmonobromogold ; but analogous cyanogen compounds are easily obtained both in the ethyl and propyl series. Monoethylenediaminotetra-7-propyldibromodigold (Burawoy and Gibson 1934) is a fairly stable colourless crystalline, 4-covalent auric compound soluble in certain organic solvents. On le. eee ee ee ee B.—CHEMISTRY 43 standing at the ordinary temperature, its solutions in chloroform or benzene slowly become cloudy due to the following change : Br Br Pre NH, 7 | NeeG 9 2 Pre—Au <- en > Au—Pr* . — = 2 Au C,H, |Br-+- | JOUR Fe Ret iPr? NH, P aa r Br P PSI GENES Au Au YE ERGB POW Pre Br Pr The salt, ethylenediaminodi-n-propylgold bromide, is insoluble in such solvents as chloroform and benzene. By repeatedly washing the com- pound with water the above change goes to completion from left to right, the di-n-propylmonobromogold being insoluble in water. The de- composition of the monoethylenetetraalkyldicyanodigold compounds follows a different course (see below). On being heated to its melting point, monoethylenediaminotetra-n-propyldibromodigold undergoes the following change : Br Br a | Pre—Au <- NH,—C,H,—H,N —> Au—Pr" | Pr2 Pre Br = a < NH,—C,H,—H,N —> Au—Br + 2 Pr’ | (CHy.) Pre The solid product of the reaction is monoethylenediaminodi-n-propyl- dibromodigold and this reaction indicated that suitable organic gold compounds may be the potential source of free radicals (see below) and that it is possible to prepare mixed auric-aurous compounds containing 4-covalent auric gold and 2-covalent aurous gold in the same molecule. While the analogous ethyl compound has not been prepared, Dr. F. H. Brain and I (1938) have recently prepared the following compounds : Br Br | Et—Au < NH,—CH,—CH, -O—CH,—CH, —H,N -> Au—Et | Et Et mono-(3’-diaminodiethylethertetraethyldibromodigold, m.p. 87°, Br Br | Et—Au < NH,—CH,—CH,—NEt, — Au—Et | Et Et mono-asym.-N-diethylethylenediaminotetraethyldibromodigold, m.p. 84°, 44 SECTIONAL ADDRESSES and both these compounds exhibit the same evolution or gas as does monoethylenediaminotetra-n-propyldibromodigold on being heated to their melting points. Other cases of the initial production of free radicals will be mentioned and their production from compounds containing two 4-covalent auric gold atoms in the molecule always results in the simultaneous production of a mixed auric-aurous compound in which the gold atoms are 4-covalent and 2-covalent respectively. Such decompositions as those just described raises the question of the possibility of establishing the existence of chlorine and bromine derivatives of gold having the formula Au,X, (formerly written as AuX, and given as examples of bivalent gold). Such halides would be mixed auric and aurous com- pounds having the constitution : oe es \ Au ot i and they may be produced as intermediate products in the decomposi- tion—not completely reversible—of the trihalides to the monohalides. The first stable salt to be isolated in this series of organic gold com- pounds was the colourless highly crystalline auric compound ethylene- diaminodiethylgold bromide, mene NH, 7 x which with its homologues has proved of utility in the preparation of the dialkyl and diaryl compounds. Although evidence of the formation of the analogous ammonia and pyridine compounds ‘Cale ts NH, Cite NC Hea x Dea (ee Au Br Au Br GEIS 1 nS OY ia b= NH, (Or 31 NCEE has been obtained they are too unstable (owing to loss of one molecule of the volatile base resulting in the formation of the non-electrolytes already mentioned) to be isolated. ‘The corresponding co-ordination compound of diethylmonobromogold with the asymmetrical N-diethyl- ethylenediamine is of special interest (Brain and Gibson 1938). The . interaction of these two substances in molecular proportions results in the production of a colourless crystalline compound soluble in water and also soluble in benzene. The compound therefore appears to be both a salt and a non-electrolyte. Bearing in mind that the co-ordinating power of tertiary amines is less than that of primary amines it might be B.—CHEMISTRY 45 suggested that its constitution should be represented in some such way as : C,H, NH, af C,H; Br rd Au C,H, 1 ia Au Mins Hla C,H; N(C,H5)» CH; NH,—C,H,—N(C,H5), This appears to be an unique case of tautomerism, of course, not reson- ance. ‘The compound, with others, is still under investigation and another anomaly remains to be explained. The compound is dissociated in aqueous solution, but shows considerable association in organic solvents (approximately bimolecular in bromoform and quadrimolecular in ben- zene), and it is suggested that the association may be explained thus : NEt, NEt, NEt, | | NH, NH, NH, | eA A ee ee | x Me AE 2 8 Ne Et Bie hte ht Et the auric gold atoms, (2), (3), etc., being 5-covalent—probably not a stable covalency—their Effective Atomic Numbers becoming 86 (the atomic number of radon) whereas the auric gold atom (1), as in a normal auric compound, is 4-covalent and has an Effective Atomic Number of 84. (4) Monoalkyldibromo compounds (Pope and Gibson 1907, Burawoy and Gibson 1934 and 1935). The monoethyl and mono-n-propyldibromo compounds have been studied in some detail. ‘They are easily prepared by the action of the calculated quantity of bromine on the dialkylmonobromogold compounds in chloroform or carbon tetrachloride solution. They are highly crystalline and deep red in colour; they are soluble in solvents which are not readily brominated or oxidised and therefore unstable in such solvents as ether, alcohol, acetone, benzene, ligroin, etc. ‘Their molecular weights (determined in freezing bromoform) show that their general formula is (RAuBr,), and the high dipole moment in carbon tetrachloride solution of the -propyl compound (u. = 6 D) affords proof that the con- stitution of these auric compounds is correctly represented thus : R Br Br Ped ioe oh” Au Au ade ook wi< R Br Br 46 SECTIONAL ADDRESSES This is in keeping with their formation from equimolecular quantities of dialkylmonobromogold compounds and tribromogold and with their physical and chemical properties. Slowly, on standing, more rapidly, in a current of an inert gas at the ordinary temperature, and still more rapidly, when heated at a temperature just above the boiling point of the alkyl bromide, they decompose quantitatively into alkyl bromide and gold monobromide, thus : Br Br << i \ oe Koes = 2 RBr+ Au Au Ye Bis This decomposition also seems to afford chemical evidence concerning the constitution of the aurous halides to which reference has already been made. ‘The aurous bromide (monobromogold) is left in a state of purity as highly crystalline apparently pseudomorphs of the monoalkyldibromo compound, and, prepared in this way, it is suitable for X-ray investigation to which such an aurous compound does not yet appear to have been submitted. Chemically, the monoalkyldibromogold compounds behave as equi- molecular mixtures of gold tribromide and the dialkylmonobromogold. For example, in contact with the many solvents which decompose them they yield dialkylmonobromogold compounds and the solvents are either brominated or oxidised and aurous bromide is left as a yellow precipitate. With hydrobromic acid, they yield hydrobromoauric acid and the dialkyl monobromogold compound and with aqueous solutions of alkali halides the reaction is similar. With ethylenediamine, they yield equimolecular quantities of the ethylenediaminodialkylgold bromide, [R,Au en]Br, and diethylenediaminogold tribromide (Gibson and Simonsen 1930, Gibson and Colles 1931), having the constitution : j~CH,—H,N NH,—CH,] | Wtsinws Au | Br, | | | Moca | | CH,—H,N NH,—CH, This is a crystalline yellow salt which is highly soluble in water and insoluble in ethanol. It is readily prepared by the action of ethylene- diamine on gold tribromide or on a suitable salt of hydrobromoauric acid. It constitutes one of the few examples known in which the 4-covalent auric gold complex is a tervalent cation in halide salts. It is analogous to tetraamminoauric nitrate, [Au(NH3;),](NO;)3, the corresponding phos- ° phate, RPO,.H,O, the oxalonitrate, R(NO,)(C,0,), the chlorate, R(C1O3)3, the perchlorate, R(ClO,)3, the oxaloperchlorate, R(ClO,)(C,O,), the sulphonitrate, R(NO,)(SO,), and the chromate R,(CrO,),; where R = [Au(NH,),]*+* (Weitz 1915). Like the above diethylenediamino com- pound, these are very stable salts ; they retain their ammonia even in the B.—CHEMISTRY 47 presence of concentrated acids. ‘The corresponding salts with the halogen acids, hydrocyanic acid and thiocyanic acid have, however, not been obtained. (c) Cyano derivatives of organic gold compounds (Gibson, Burawoy and Holt 1935, Burawoy, Gibson, Hampson and Powell 1937). By the direct action of silver cyanide on the dialkylmonobromogold compounds, the corresponding cyano derivatives are easily prepared. These compounds have unique properties and the detailed investigation of the ethyl and n-propyl compounds have revealed a number of interesting features in connexion with the general chemistry of gold. The dialkylmonocyanogold compounds are colourless highly crystalline non-electrolytes, soluble in hydrocarbon solvents, and their molecular weights in freezing bromoform are four times those required by their empirical formula. These compounds, therefore, unlike any other gold compounds so far described contain four atoms of tervalent gold in the molecule. In the molecule of such compounds, the gold atoms must be attached to the carbon atoms of the cyanogen groups and the nitrogen atoms must be co-ordinated to neighbouring gold atoms. Constitution (I) (R = Et, Pr*) indicating a symmetrical twelve atom planar ring structure is the only possible one in keeping with the stereo- chemical configuration of the cyanogen group, with the small dipole moment—y = 1°47 D in carbon-tetrachloride at 25° for the n-propyl compound—with the 4-covalency of auric gold atoms and, as will be pointed out later, with the results of X-ray crystallographic investigation. R R | R—Au—C=N-> Au—R t | CN CN N Cc | | II II R—AuAu—R R R R—Au Au—R R—Au—C=N-> fe | + if C N C II [II == 4! P ||| {|| 3 ——> 4R’ + N R—Au Ai R R t N I IV {|| 8 o. Au<+N=C—A CN CN 7 R NEG a | | Nea : R—AuAu—R —>2R’+ Au WCE, Au(CN), | | ye EON R R LR NH, II VI The dialkyldicyanodigold compounds (IV) are non-electrolytes like the dialkyImonocyano-gold compounds (I), but unlike the latter they are very sparingly soluble in organic solvents and they decompose without melting. ‘They constitute further examples of mixed 4-covalent auric and 2-covalent aurous compounds. The decompositions I > IV + V afford chemical evidence regarding the constitution of monocyanogold (gold monocyanide, aurous cyanide), indicating that it is a non-electrolyte, that it is a 2-covalent aurous compound and that there are four such gold atoms in the molecule which like that of a compound of type (I) is planar. Pure gold monocyanide prepared in such a way should be suitable for X-ray crystallographic investigation. The ethylenediaminodialkylgold B.—CHEMISTRY 49 aurocyanides (VI) are electrolytes and mixed 4-covalent auric and 2-co- valent aurous compounds, a type of compound of which the first example appears to have been described by Sir William Pope in 1929. It will be appreciated that the conversion of compounds of type VI into those of type IV by means of acid, which goes quite smoothly, is somewhat complicated involving changes of electrovalencies into covalent and coordinate linkages. The free radicals were not identified as such although there is evidence for believing that they are initially evolved. ‘The decompositions are of either solid or liquid compounds and so far free radicals have only been identified as such when they have produced by decompositions in the vapour phase. Actually the free radicals were identified as the paraffin hydrocarbons to which they should give rise, m-butane from the ethyl derivatives and n-hexane from the m-propyl derivatives. This was the first time that n-hexane had been obtained from the decomposition of a n-propyl compound. Previously, when n-propyl radicals had been anticipated as likely to be produced a mixture of ethane, butane and ethylene (Frankland 1877) or a mixture of only ethane and ethylene (Paneth and Lautsch 1931) had been obtained. (d) The structure of gold compounds. During the past two years, our knowledge of the structure of various types of gold compounds has developed considerably as a result of X-ray crystallographic investigations. ‘Those on the organic compounds are being carried out at Oxford by Powell (1937) and his collaborators, those on Mann’s co-ordination compounds of aurous gold at Cambridge by Wells (1936) while Cox and Webster (1936) have carried out their investi- gations on potassium bromoaurate at Birmingham. ‘These investigations have established the planar configuration of the four valencies of tervalent gold and the linear configuration of the two valencies of aurous gold. The X-ray investigation of the simplest organic gold compound, diethylmonobromogold, is attended with difficulties arising from the instability of the crystals to X-rays and even to light. In spite of these, Powell has been able to carry out his analysis satisfactorily. The results, are summarised in figures (1) and (2), reproduced by permission of the Chemical Society. The orientation of the molecule in the unit cell is indicated in the perspective diagram (Fig. 1) where, for convenience, the origin has been moved to } $ 4. The molecule, projected on the plane of the gold and bromine atoms, is shown in Fig. 2. ‘The carbon atoms marked @ and © are, respectively, above and below the plane of the other atoms. The distances marked on Fig. 2 are subject to a probable error of +0-1 aA. The results show that two gold atoms and two bromine atoms lie close together near the origin and that the mole- cule is Au,(C.H;),Br,. These four atoms form a rough square in a plane somewhat inclined to (oor). In order that the molecule may fit into the unit cell, all the atoms must lie approximately in one plane as is shown by the very small c dimension, and the four gold valencies must accordingly lie in one plane and will be approximately at right angles to one another. The suggested structure is in agreement with the needle habit of the crystals 50 SECTIONAL ADDRESSES and the very high negative double refraction with the smallest refractive index roughly along the needle direction. ‘The molecule thus has a centre of symmetry and the structure deduced from molecular weight determina- tion and electronic structure is fully confirmed, although the substance has a small but definite dipole moment. The planar and symmetrical distribution of the four valencies of tervalent gold in a non-electrolyte thus confirmed the same results obtained by Cox and Webster in the case of the salt, potassium bromoaurate, KAuBr,.2H,O. The crystallographic investigation of the much more complicated com- pound, di-z-propylmonocyanogold, (Pr*,AuCN),, has only recently been completed by H. M. Powell and R. F. Phillips and the results, which will be published in detail later, strikingly confirm the constitution deduced from the chemical and especially the physical properties of the substance. Cc t M4 Eire. re Biel 2. Di-n-propylmonocyanogold crystallises in the polar class of the ortho- rhombic system: ‘The unit cell contains sixteen Pr,AuCN units. Oscil- lation photographs and Weissenberg photographs about the three principal axes show the absences characteristic of the space group, Pca. The photo- graphs were obtained with copper radiation and intensities estimated visually with the aid of a photographic intensity scale. A two dimen- sional Patterson analysis on the (hkO) spectra gave approximate a and b axis coordinates for the gold atoms and signs of the F(,,0)’s could there- fore be determined and the corresponding two dimensional Fourier synthesis carried out. Two successive approximations led to the final Fourier projection, Fig. 3. This shows the association of four gold atoms” in one molecule, the peaks corresponding to the gold atoms lying at the corners of parallelograms in the projection suggesting that the plane of the molecule is considerably inclined to the plane of projection (oor). The lighter carbon and nitrogen atoms are not resolved being, in any case, largely overlapping. Ridges of electron density indicate the 51 B.— CHEMISTRY ‘wo1qoalfoid jo ourjd oy} 0} oArTZeTeI VINOITOUI 9Yy} JO 4 2YY 0} SUIMO potez1oyser0y sreadde orenbs oy], ‘“papeys A[IAvoy JOU Siay}ZO eAOqe SutAT sojnosjour s}usseid ‘soul, UexoIq Aq UMOYS IN0jU09 jsaMo] -o1 Suipeys Aaeofzy *(100) wo sinzonIys Jo ux[G—'hb “O17 ay} ‘(100) uo pozoford Azsuap uos0a9[9 VATZeJaY—"E “OT H ) @-N @-9 52 SECTIONAL ADDRESSES Au—C=N -+ Au group of atoms and the positions of the propyl groups are shown to be : Pre | — (CSS) = A SS Ie | C (|| N The projections on (100) and (oro) are non-centrosymmetric, but owing to the overwhelming influence of the gold atoms, whose ¢ co- ordinates can be estimated, the arbitrary phase constants corresponding to the Foyy’s and Fooy’s can be calculated for the completion of the projection on (o10) and (100). ‘The three projections so obtained give the coordinates of all the gold atoms and indicate approximately the positions of the carbon and nitrogen atoms. Consideration of these projections and of the space available permit the assignment of coordinates to all atoms. Between atoms in different molecules there is no approach less than the usual 3-6 A. The Fourier analysis shows clearly the general positions of the n-propyl groups and the ‘ square’ character of the gold valencies, but it must be understood that the details concerning the terminal parts of the n-propyl groups is only suggested to be as indicated, alternatively tilted above and below the plane of the square, in order to leave sufficient space between molecules (Fig. 4). The shape of the molecule approximates to a real square and the distance, Au—C=N-—>Au, is the same for each side and equal to 5-18 a, thus confirming the suggested formulation, Au—-C=N — Au, which, from available data on bond lengths, should require 5-28 a. (e) Among the studies of gold derivatives of organic sulphur com- pounds being carried out in my laboratory, I will only refer to one which presents certain unusual features. My collaborators and I have studied the reactions which may be briefly outlined, thus : ; Bz,S — Au—Br A I nN Jf 4 \ o/ / | Ne S lz |e ey, “%, Rely / Rey ne) 3 LZ aS %, oS | ® is %, . By | 2 “i ‘ / yi | , 2 th ane | ABE SA uBio es aes a Aue LBs (Bz,SAuBrl), IV NBs Ul Analogous substances have been previously prepared by different authors. Substance (IV), for example, was described by McPhail —— Oe ———— — — —— — — LL B.—CHEMISTRY 53 Smith (1922) as ‘ dibromogolddibenzylsulphide,’ an addition compound of ‘gold bromide’ ‘to which was assigned the formula, Br,Au.SBz,. On the other hand, Ray and Sen (1930) described the chlorine analogue of the same substance as auroaurichloride dibenzyl sulphide having the constitution, AuCl,Bz,S.AuCIBz,S. Ray and Sen, however, stated that the molecular weight of their substance agreed with the molecular formula they assigned to it. This does not agree with the results obtained. by previous workers nor by Dr. Tyabji and myself for the bromine analogue (1937). There is nothing unusual concerning the structure and properties of the colourless 2-covalent aurous compound (I), (dibenzylsulphidomono- bromogold), or of the structure and properties of the deep red 4-covalent auric compound (II), (dibenzylsulphidotribromogold) ; but the structure and properties of the substances (III) and (IV), which, as compounds, would be termed bis(dibenzylsulphidobromoiodogold) and bis(dibenzyl- sulphidodibromogold) respectively, present interesting features. Of these, only (IV) in which the halogen atoms are the same needs to be con- sidered in detail. All these substances are non-electrolytes and (IV), in addition to the method already indicated, can be prepared by mixing equimolecular quantities of compounds (I) and (II) in a suitable solvent, for example chloroform. The molecular formula of (IV) cannot be the same as its empirical formula otherwise it would be a 3-covalent derivative of bivalent gold. The apparent molecular weight of each of the substances (III) and (IV) in freezing bromoform is a little less than that indicated by the empirical formula affording no information as to their constitutions. In this particular case, our knowledge of the chemical and physical properties is inadequate for determining the constitution of the sub- stance in the solid state. All that is possible is for the chemist to suggest reasonable alternatives based on recognised principles of the constitution of co-ordination compounds. None of these alternatives is capable of being confirmed by chemical or physico-chemical methods and the only method of determining the constitution is by careful crystallographic and X-ray analysis. In the solid state the substance is obviously a mixed aurous- auric complex of a new type, since the mixed aurous-auric compounds already encountered are stable both in solution and in the solid condition. For the constitution of the substance in the solid state, two not un- reasonable possibilities immediately suggest themselves. In the linking up of the aurous and auric compounds, (a) the aurous gold atom may become 4-covalent, its four valencies probably assuming a tetrahedral configuration, having now eight electrons in its outer shell and assuming an Effective Atomic Number of 86, or (4) the auric gold atom may become 5-covalent, its five valencies probably assuming a pyramidal con- figuration, having now ten electrons in its outer shell and assuming an Effective Atomic Number of 86. I have put the two alternatives in this order, because there seemed to be a possibility, if crystallographic and X-ray analysis proved it, of obtaining the first incontrovertible evidence of a 4-covalent aurous com- pound which, up to the present, remains a theoretical conception un- supported by experimental evidence to explain the constitution of certain complex compounds (compare p. 37). Arising from suggestion (@) there 54 SECTIONAL ADDRESSES are two ways in which the two compounds may be linked together in the complex. In the one case, the gold atoms may be connected thus: Br ata Au te 4 Br Au the aurous gold atom having four valencies—two co-ordinately attached bromine atoms (shown), a co-ordinately attached sulphur (of dibenzyl- sulphide) atom and a covalently attached bromine atom—tetrahedrally disposed, while the auric gold atom has its four valencies in a plane, three being covalent links attached to bromine atoms and a co-ordinate link from the sulphur atom of dibenzylsulphide. The dissociation of the complex in non-aqueous solvents might then be explained by the particular disposition of the co-ordinate Br —> Au links since, in the stable mixed aurous-auric compounds already known and some of which have been referred to above, such linkages are alternately disposed thus : Br yi Au Au Ress Br In the other case arising from suggestion (a) the solid complex may consist of alternate auric and aurous units linked together by co-ordination of a bromine atom from the former to the latter, each aurous unit being linked to two auric units. ‘The simplest possible molecule would thus be a ring containing two auric and two aurous units thus : Br SBz, | Bz,S->Au—Br->Au—Br Denideraeital Br Br v | Br—Au<-Br—Au8o 1936-7 1,700 56 6 <20 >8o 1937-8 28 I 9°5 The significant point in this Table is, however, the marked change in the composition of the catch which began in 1931-32—that is to say in the winter of the year in which the summer spawning fish larvae showed their first signs of decline. Prior to 1931-32 the younger herring, not more than six years old, always formed at least two-thirds of the catch. In that season the younger fish were only 52 per cent. of the total and from then on there has been a rapid deterioration, until to-day there are less than 20 per cent. of the younger and more than 80 per cent. of the older. 3 E. Ford, ‘ An Account of the Herring Investigations conducted at Plymouth during the years from 1924 to 1933,’ Journ. Marine Biol. Assoc., XIX, p. 373 (1933). 4 Data obtained by E. Ford. go SECTIONAL ADDRESSES This change in the constitution of the herring shoals was not immediately reflected in the size of the catches, which for some years were maintained at a good level by the considerable stocks of older fish. But as these passed out they were not replaced by any adequate numbers of the younger year classes and in recent years the fishery has been profoundly affected. Formerly the number of Lowestoft drifters which visited Plymouth for the herring season rarely fell below 75 and was sometimes well over 100; during the past season only one came. And in similar fashion the weight of fish landed has fallen from a figure which sometimes reached 80,000 cwt. to one of under 30 cwt. It is interesting and perhaps significant to note that as Mr. G. P. Farran has shown ® the stock of herring on the north coast of Donegal has shown a pronounced decline in recent years. ‘The decline began in 1930, some eighteen months before the change in the constitution of the Plymouth shoals was first seen, and the industry based on this fishery has suffered greatly. Conditions at Plymouth and on the Donegal coast are not identical, for the successful spawning seasons in the latter area were 1920, 1924 and 1925, whereas at Plymouth they were in 1920, 1923 and 1925. The annual fluctuations have thus not operated in exactly the same way. Mr. Farran tells me, however, that the shortage of herring in recent years has been accompanied, just as at Plymouth, by a great reduction in the numbers of the earlier year classes, and it is thus possible that the same long period fluctuation is affecting both areas. Since 1931, when the depression in the Plymouth area began, there has been a marked change in the amount of phosphate in the offshore waters. Records made by Dr. W. R. G. Atkins and Dr. L. H. N. Cooper show that the phosphate is at its maximum in the winter, in December and January, and since the phytoplankton crop is limited by the amount of phosphate in the water, the winter records give a good indication of the quantity of food which will be available for fish larvae. The records show a heavy decrease in phosphate beginning in 1931, and, as seen in Table II, there is an evident relation between the amount of phosphate and the abundance six months later of the larvae of summer spawning fish. If the average phosphate values for the two four-year periods 1924-27 and 1934-37 are compared we find that the decrease has been about 35 per cent. ‘The fact that the larvae of summer spawning fish were the first to feel the adverse conditions, and that those of the spring spawn- ing fish were not seriously affected until 1935, can in theory at least be explained in terms of nutrient salts; a reduced crop of phytoplankton will mean a smaller supply of zooplankton, and this will mostly be con- sumed by the spring larvae, leaving little or none for those that come later in the year. : The herring on which the Plymouth fishery depends are mature fish running up Channel to their breeding places on the Cornwall and Devon coasts. On this migration they are not feeding and, presumably, they are unaffected by plankton conditions. It is possible that the disastrous change which has occurred is due to a long series of unproductive spawning * seasons caused by the abnormal conditions of the Channel water and lack 5 G. P. Farran, ‘ The Herring Fisheries off the north coast of Donegal,’ Journ. Dept. Agriculture for Iveland, XXXIV, no. 2 (1937). D.—ZOOLOGY o1 of food for the larvae ; if that is so the herring has failed in exactly the same way as the other fish whose larvae Mr. Russell has studied. There are, however, reasons for believing that this may not be the correct explana- tion, for the herring spawn in winter and thus differ strikingly from the majority of fish we have been considering. ‘They are evidently able to find sufficient food at a time when the plankton is at a minimum and they are not dependent on the rich zooplankton which follows the spring outburst of phytoplankton. It is perhaps more probable that the earlier year classes of herring have responded to the abnormal conditions in the Channel by forsaking their usual line of migration, and that they now go to other spawning grounds. TasB_e II. _ Phosphate axe Ceca) 7 Sagitta in preceding Year winter ¢ % deviation}; Summer Spring Total no.® | S. elegans S. setosa from mean | Spawners Spawners + 1000 % % 1922 | > + 16 1923 | > +27 1924 + 27 696 2,133 1925 +9 140 1,510 1926 | + 36 909 2,051 1927 = 2 170 1,014 1928 | + 23 Ls in 1929 | + 23 321 502 1930 - 403 1,114 g's 9471 5°9 1931 | —7 230 1,395 L728 ical 20°7 83°3 M320. 16 197 1,359 118°3 6:2 93°8 1933 aid 117 1,220 I17"4 4°7 95°3 1934 | — 14 79 1,065 94°5 3°5 96° 5 1935 | — 25 37 393 48-2 3°6 96° 4 1936 | — 16 115 372 24.°0 39°7 60°3 BO37| 114 174 382 26°1 3°8 96-2 #938 | — 16 Renewal of the phosphate in the Channel appears to be largely depend- ent on an inflow of mixed Atlantic water, which is rich in phosphate because it contains water that has upwelled at the edge of the continental 6 For further particulars see L. H. N. Cooper: ‘ Phosphate in the English Channel, 1933-38, with a comparison with earlier years,’ Journ. Marine Biol. Assoc., XXIII, 1938 (in press). 7 The numbers of young fish caught in half-hour oblique hauls of the standard 2-metre net, expressed as the sums of the monthly average catches. Hauls were made weekly, so far as possible, the number varying from 42 to 52 per annum. [Data by F. S. Russell, published in part in Conseil Internat. Mer, Rapp. et Proc.- Verb. des Réunions, C, part 3, p. 9 (1936)]. 8 The total number in the standard hauls referred to above. Data by F. S. Russell. 92 SECTIONAL ADDRESSES shelf ; and from the evidence I have laid before you it seems probable that the normal water movements off the mouth of the Channel have undergone marked alteration in recent years. Direct proof of this is lacking, for we have no observations in the waters to the west of the Channel, but evidence of it is afforded by the very interesting discovery which Mr. Russell has made that certain planktonic species may be used as indicators of water-masses.’ A relation of this kind has been found in a number of plankton species, but it is here only necessary to refer to those belonging to the genus Sagitta, and these owing to their abundance are the most useful. Of the species of Sagitta, S. serratodentata is typical of the open Atlantic, S. elegans of the mixed Atlantic water and S. setosa of the Channel water. _ The first of these is only to be found on rare occasions off Plymouth when the inflow of Atlantic water is exceptional. The importance of the species of Sagitta as indicators of water move- ment was first recognised by Prof. Meek, but Mr. Russell’s data from Plymouth only began in 1930, and the records are therefore not as com- plete as could be desired. It is, however, known that for some years prior to this date the offshore plankton in the neighbourhood of Plymouth was of the kind characteristic of the mixed Atlantic water: it was a very rich plankton with such forms as Meganyctiphanes and Aglantha. It was this type of plankton which was found in 1930, and in the regular series of tow-net hauls made in that year Mr. Russell found that there was 94 % of S. elegans and only 6 % of S. setosa. In the following year, when the deficiency of phosphate and of summer spawning fish larvae first became manifest, there was, as will be seen from Table II, a conspicuous change in the Sagitta population: of S. elegans there was only 17 % while there was 83 % of S. setosa. Since then S. setosa has always greatly preponderated in the catches, with a percentage of 93 or over, with the single exception of 1936, when there was 60 % of S. setosa and 40 % of S. elegans. ‘There is no doubt there was a small incursion of mixed Atlantic water in the Channel in this year, but it was apparently insufficient to alter the trend of events. Attention may be drawn to the high sensitivity of this new method of distinguishing water-masses. Once the distinctions between the species of Sagitta have been mastered it is an easy method to handle, and it will no doubt be widely employed in the future. We thus have evidence from four separate sources of the changed conditions which have prevailed in the Channel since 1930-31. These sources are (i) the winter phosphate maximum; (ii) the numbers of fish larvae ; (iii) the constitution of the spawning herring shoals ; and (iv) the predominance of one or other species of Sagitta. The picture, to my mind at least, is convincing: one gains the impres- sion that if only we had fuller knowledge corroborative data from many biological sources would be forthcoming. The view that the large alteration which has occurred is linked with 9 F. S. Russell, ‘ On the Value of certain Plankton Animals as Indicators of Water Movements in the English Channel and North Sea,’ Journ. Marine Biol. Assoc., XX, p. 309 (1935); ‘Observations on the Distribution of Plankton Animal Indicators . . . in the Mouth of the English Channel, July, 1935, ibid., XX, p. 507 (1936). D.—ZOOLOGY 93 hydrographical changes is corroborated from farther afield. Since 1926 continuous records of the currents in the Straits of Dover have been made from the Varne Lightship with the Carruthers drift indicator. Water can enter the North Sea both from the English Channel and round the north of Scotland and Dr. Carruthers infers that these water-masses are opposed to one another and act in a sort of ‘ buffer relationship.’ At the Varne Lightship the relative strengths of these two forces are indicated by a change in the direction of the current. Dr. Carruthers 1° has calcu- lated the direction of the residual current for each year since 1926 and the figures which he has given show that from 1931 onwards this residual current has swung towards the north and has considerably less of the easterly component which it possessed in the earlier years when high winter values for phosphate were observed at Plymouth. A point worthy of consideration is whether a similar series of adverse years has occurred in the past, but on this unfortunately we have no reliable data. The statistics of the herring industry are almost the only source open to us, for we have no regular observations on fish larvae prior to 1924, and it was not until five years later that the importance of Sagitta was recognised. But before the War, the herring industry was conducted on different lines, from sailing vessels, and we have figures only for the aggregate catch from which it is not possible to draw any conclusions. In 1915 and 1916 Mr. D. J. Matthews first began the determination of phosphate in Channel water. His results, though not obtained by the methods now in use, have a high degree of accuracy, and they suggest that in those years there was a deficiency of phosphate comparable with that in recent times. Unfortunately the Plymouth herring fishery was greatly reduced during the period of the war and we have no reliable statistics for comparison. We may suppose that this long-period fluctuation at the mouth of the Channel will end in due course, but we have no means of knowing when this will happen. When the change comes it will be heralded, we believe, by the return of Sagitta elegans in large numbers, and by a marked increase in the winter phosphate maximum. The fisherman will presumably not find any immediate improvement in the bottom fish. As yet he has perhaps scarcely realised the full extent of the depression which started some years ago, and when there is a return to better conditions he must wait until the increased numbers of larvae grow to fish of marketable size. It is possible, however, that bottom-living fish have been migrating into the area and that he may thus in some measure escape the worst effects of the depression. If the younger herring have forsaken their spawning grounds and gone elsewhere, we may hope that they will at once return in force when conditions improve, and that the Plymouth fishery will rapidly be re-established. If, however, they have throughout held to their former migration routes, and the present dearth is due to lack of suitable conditions for the larvae, they are in the same position as the bottom fish and a number of years must elapse before the fishery can be resumed. 10 J. N. Carruthers, ‘ The Flow of Water through the Straits of Dover,” Part II. Min. Agric. Fisheries, Fishery Invest., ser. ii, XIV, pp. 15, 64, Table VI (1935). 94 SECTIONAL ADDRESSES You will, I think, have noticed that in this outline of recent events I have made no reference to other hydrographical data, such as salinity and temperature, and I must needs do so now lest you suspect me of suppressing evidence which is not in accord with the story I have told you. For the plain fact is that the observations we have of salinity and temperature do not fit into the picture. For many years past Dr. H. W. Harvey has followed the temperature and salinity changes at the western end of the Channel,1! and during the period since 1924 he has found that the most conspicuous movements were large incursions of low salinity water in May 1928 and in March and April 1936, while in 1932, 1933 and 1934 (especially in 1933) patches of water with unusually high salinity moved eastwards up the Channel. So far as can be seen these movements show no correspondence with the marked biological changes which have occurred : it is in the phosphate data only that a correlation can be found. In the year 1921 there was an exceptional influx of Atlantic water, which filled the Channel1 and flooded into the North Sea. Salinity and temperature were much above normal and numbers of unusual planktonic organisms of Atlantic origin were found in the North Sea.1* Recent experience at Plymouth might lead one to think that such an influx as this would bring benefit to the herring fisheries, but actually it was just the reverse, for at Plymouth and in the North Sea, at Lowestoft, Yarmouth, Grimsby and North Shields, the herring fishery was much below normal.14 In recent years also a number of unusual planktonic forms have entered the Channel, brought apparently by incursions of low salinity water flowing round Ushant ; but these movements have had no effect on the depleted phosphate supply. It thus appears that incursions of Atlantic water into the Channel may bring advantage to the biology of the area or may be detrimental, that no obvious connection between the biological data and temperature and salinity is noticeable, and that so far as we can at present see the only correlation that can be established is with phosphate. The ex- planation lies, I believe, in our very considerable ignorance of the constitution and origin of the water-masses which from time to time enter the Channel. There is evidently more than one way in which an influx of Atlantic water may be advantageous. It may, in the first place, bring water with a high content of phosphate and other nutrient salts which will subse- 11H. W. Harvey, ‘ Hydrography of the Mouth of the English Channel, 1925-28 and 1929-32,’ Journ. Marine Biol. Assoc., XVI, p. 791 (1930); XIX, p. 737 (1934). 2 J. R. Lumby, ‘ The Salinity and Temperature of the Southern North Sea and English Channel during the period 1920-21,’ Publications de Circonstance, no. 80 (1923). 18 A, C. Hardy, ‘ Notes on the Atlantic Plankton taken off the east coast of . England in 1921 and 1922,’ zbid., no. 78 (1923). 14 J. R. Lumby, ‘ Salinity and Water Movements in the English Channel during 1920-23,’ Min. Agric. Fisheries, Fish. Invest., ser. 2, VII, no. 7) P- 18, fig. ix (1925). H. W. Harvey, ‘ Hydrography of the English Channel,’ Conseil Internat. Rapp. et Proc.-Verb. des Réunions, XXXVII, Rapp. Atlantique, 1924, pp. 82-84 (1925). D.—ZOOLOGY 95 quently yield an abundant plankton. Or, secondly, though deficient in phosphate, it may bring in large quantities of phytoplankton or zoo- plankton, the product of a former richness in phosphate. This plankton will afford an immediate food-supply for larval fish and other animals, and when it dies down the phosphate will be regenerated and will serve for further plankton production in the future. It is thus what we may call the biological condition of the water that is of importance, and this no doubt is to some extent determined by the season of the year. At times, in summer, the surface water may be largely devoid of both plankton and phosphate and an influx of such water, even though its high salinity may indicate an oceanic origin, will bring no improvement to biological conditions and may indeed be harm- ful. In winter, when the thermocline has broken down and surface phosphate has been renewed by convection and by stormy weather, an influx may prove of advantage. But it is perhaps more probable that upwelled water, rich in the nutrient salts which are always to be found in the lower layers of the ocean, is the potent source of surface enrichment, and of the conditions in which such upwelling occurs we are very largely ignorant. We lack the necessary data and can merely speculate on what may be happening from analogy with what is known in other areas. Some twenty-five or thirty years ago Mr. D. J. Matthews !° published a series of papers on the physical conditions in the English Channel and adjacent waters, and to this day his work remains one of our principal and most valuable sources of information. He showed that to the south of Ireland there is an extensive cyclonic or counter-clockwise circulation, which may at times reach as far south as 484° N., and nearly a quarter of a century ago he suggested that this circulation might prove of consider- able biological importance. ‘ If the strength of the cyclonic system varies from year to year, so will the character of the water at any place within its influence, such as the areas of the drift-net fishing off the mouth of the English Channel and off the south coasts of Ireland.’ There can scarcely be a doubt that the vagaries of this circulation have a profound effect on conditions in the Channel. If we possessed, as unfortunately we do not, a continuous series of observations on the oceanographic conditions to the south of Ireland and on the edge of the continental slope, the variations in this cyclonic system could be traced, and even though it might then appear that the ultimate causes of the present depression are linked with changes in the Atlantic circulation, and thus still out of reach, the information which would be gained would un- doubtedly throw new light on the problem. I have dwelt at some length on these events in the Plymouth area because they afford a good example of a long-period fluctuation and illustrate the way in which observations drawn from widely different lines of inquiry are linked together. From other sources also there is 18 PD. J. Matthews, ‘ Report on the Physical Conditions in the English Channel and adjacent Waters in 1903: in 1904 and 1905: in 1906,’ Internat. Invest. Mar. Biol. Assoc., Rep. I, 1905; Rep. II, part ii, 1909; Rep. III, 1911. ‘ The Surface Waters of the North Atlantic Ocean, South of 60° N. Lat., Sept. 1904 to Dec. 1905, ibid., Rep. II, part i, 1907. ‘ The Salinity and Temperature of the Irish Channel and the waters South of Ireland,’ Fisheries, Ireland, Sci. Invest., 1913, lv, I9I4. 96 SECTIONAL ADDRESSES good evidence of long-period fluctuations in fisheries, and though the hydrographical changes to which they may ultimately be traced are not, as it appears, the same as in the Channel, they show that major alterations extending over a long term of years are by no means unusual. In 1925 the Norwegians discovered great numbers of cod on the banks surrounding Bear Island, and ever since that year, except in 1929 when ice interfered with the operations, the fishery has been maintained, many trawlers visiting the banks annually to take toll of their wealth. Iverson,1¢ from whose paper my information on this fishery is derived, states that there was a former occasion when cod were plentiful in this area. That was from 1873 to 1882. Between 1883 and the time when the present fishery began the grounds were examined on a number of occasions, but very few cod were found and the results were unprofitable. It was so in 1924, the year which preceded the present period of abundance. Another instance is afforded by the cod fishery in West Greenland. At certain times large concentrations of cod appear on this coast and spread as far north as Disko Bay, affording a profitable fishery ; but after a term of years their numbers suddenly decline and a protracted period of scarcity follows. In 1917 cod were found in West Greenland in great abundance and the fishery on this coast has been maintained up to the present day. Prior to that, as Jensen and Hansen show in their interest- ing historical account,!’ the grounds were tested on a number of occasions without finding stocks of cod in marketable quantity ; but early records indicate that there were at least two periods, in 1820 and in 1845-49, when cod were present in great numbers. In recent years it has been found that some of the cod spawn in Greenland waters, while others migrate for this purpose to Iceland. Marking experiments show that there is an interchange of cod across the Denmark Strait, and there is reason to believe that most of the fish found on the Greenland coast during periods of abundance have come from Iceland, either as fry carried in the west- going current or by migration of mature fish.1® To these two instances of large-scale changes in the fish population in northern waters many others could be added and all are apparently due to the same cause—to the fact that in recent years the entire area from Greenland to Bear Island has become appreciably warmer. Berg 1° has collected much information on the effects of this rise in temperature, Saemundsson 2° has given an interesting account of the alterations which have occurred in the fauna of Iceland, while Stephen 24 has shown that marked changes have also taken place in the British marine fauna. Berg, quoting from Schischow, gives figures of the very 16 T. Iverson, Rep. Norwegian Fishery and Marine Invest., IV, no. 8 (1934). 17 S, Jensen and P. M. Hansen, ‘ Investigations on the Greenland Cod,’ Conseil Internat. Rapp. et Proc.-Verb. des Réunions, LX XII, pp. 1-41 (1931). 18 E. S. Russell, ‘ Fish Migrations,’ Biol. Reviews, XII, pp. 324-5 (1937). 19 L. S. Berg, ‘ Rezente Klimaschwankungen und ihr Einfluss auf die geo- graphische Verbreitung der Seefische,’ Zoogeographica, III, Heft 1, pp. 1-15 1935)- as Saemundsson, ‘ Probable influence of change of temperature on the marine fauna of Iceland,’ Conseil Internat. Rapp. et Proc.-Verb. des Réunions; LXXXYI, no. I, pp. 1-6 (1934). 21 A.C. Stephen, ‘ Temperature and the incidence of certain species in Western European Waters,’ Journ. Animal Ecology, VII, p. 125 (1938). D.—ZOOLOGY 97 remarkable increase in the herring taken on the Murman coast since 1931. The quantities taken in that year and in 1932 and 1933 were respectively 23 times, 29 times and 68 times as great as the largest catch in the ten preceding years. It is clear that an increased sea-temperature, probably of the order of 1:0 to 2:0°C., has allowed various species of fish to extend beyond the normal limits of their distribution, with the result that it has been possible to establish productive fisheries in areas which formerly would not have yielded an adequate return. It is evident, I believe, that at some future date conditions will revert to normal and that a time will come when these lucrative fisheries will cease to exist. In the present state of our knowledge we can do little more than guess at the reasons for the increased temperature in these areas ; but the only source from which warm water can come is the Atlantic drift, and it therefore appears that in recent years this drift must either have increased in volume, or, if the volume remains constant, in the temperature of the water it carries. é As you will have seen, I have in this address tried to draw a distinction, which I believe to be a real one, between two kinds of fluctuations, both of which have a pronounced effect on the marine fauna. Normal annual fluctuations are a constant feature. They form the basis of fishery pre- diction and our information, such as it is, is that their incidence is restricted: a fishery for a certain species in a particular place will be affected, while other species in the same place, or the same species in another place will be unaffected. And it is to be assumed that the causes of such annual fluctuations, though of these we know but little, are also restricted both in space and in time. In contrast are what I have called long-period fluctuations, which extend over a term of years and involve much larger areas. Such fluctuations as these are due to a widespread change in one or more of the hydrographic factors in the environment, and large numbers of species, if not all, are affected simultaneously or within a short period. Long- period fluctuations may mask the effects of the annual fluctuations and at times they will render fishery prediction unreliable. In the illustrations I have given you I have spoken chiefly of fish, because it is of fish that we have best knowledge ; but it will I think be evident that invertebrates are influenced in the same way and I believe it may truly be said that all marine animals show great variations in abund- ance. You will also not fail to note that though these fluctuations are of the greatest economic importance they are equally of very high scientific interest. The evidence I have given you indicates that long-period fluctuations may be brought about in entirely different ways. In the Channel, as it appears, the change can be traced to a deficiency in phosphate, while in more northerly areas it is due to an increase in sea-temperature. But, though there is this wide difference, the two sets of circumstances have this in common, that they originate in the open Atlantic, at the edge of the continental slope or farther to the west. It is here, in oceanic waters, that the causes of these large alterations in European fisheries must be sought. E 98 SECTIONAL ADDRESSES Vladivostok, though it is ice-bound each winter, lies in the same latitude as Marseilles. ‘This is only one of many facts which impresses us with the climatic advantages that we derive from the warm water of the Atlantic drift, and it might be thought that an investigation of the causes which underlie this phenomenon would long since have been undertaken by those who reap such great benefit. Yet, to the present day, these problems remain unsolved and, as Dr. Iselin has recently shown,?? three mutually conflicting theories are extant regarding the circulation of water in the North Atlantic. Fortunately there are signs that a period will be set to our ignorance. On the American side of the Atlantic the Woods Hole Oceanographic Institution is making a study of the Gulf Stream and of the effect of wind velocity and direction on the strength of a current. There is to be British co-operation in this programme, based on the Bermuda Biological Station. The Royal Society is administering a Government grant which has been given for the purpose, and additional staff for the Bermuda station and a small research ship have been provided. Data recently obtained by the Woods Hole Institution show that the transport of water in the Gulf Stream has varied by as much as 20 per cent. in fourteen months, and it may well be that this figure is below the normal range of variation. When the observations over the five-year period which is contemplated have been carried out we may hope to know far more than we do at present of the Gulf Stream and its effects on circulation in the North Atlantic. During the present year a German research ship is making a prolonged investigation of the hydrography of the North Atlantic, and only two months ago research ships from Denmark, Norway and Scotland were co-operating with her in studying extensive areas from the Azores to Iceland. From such combined attack we shall learn much and there is every reason to believe that the main features of the circulation in the North Atlantic will shortly be understood. But though we may look for results of the highest importance from these investigations it is evident that they will not solve the biological problems with which we are faced ; for the work in the eastern Atlantic is an isolated set of observations, most valuable as a contribution to our knowledge of the general conditions, but affording little help in solving the problem of long-period faunistic fluctua- tions of which I have spoken. It is the deviations from the normal which are of paramount importance to the biologist, and it is only by repeated observations made over a series of years that they can be detected. To make such observations at sufficiently close intervals of time and space over the whole of the north-east Atlantic is clearly not within the bounds of present possibility; but when we have gained an adequate knowledge of the normal system of circulation it is to be expected that certain critical positions or regions will be discovered, and that regular data from those places will give information from which the variation in the whole system can be deduced. Even such a programme as this is far beyond the resources we now possess ; but I believe that the need for 22 C. O’D. Iselin, ‘ Problems in the Oceanography of the North Atlantic,’ Nature, vol. 141, p. 772 (1938). D.—ZOOLOGY 99 systematic oceanographic work in the eastern Atlantic will be more and more acutely felt as time goes on, and I feel convinced that it is the only way in which we can ever reach an understanding of the reasons for the large fluctuations in our fisheries. There is much work to be done nearer at hand in improving and co-ordinating the collection and publication of data from our own coastal waters—a matter to which the International Council for the Exploration of the Sea is now giving careful attention. It appears, however, that the research ships employed by the maritime countries of Europe are for the most part fully occupied with their own domestic fishery problems and can only occasionally find opportunity for oceanographic survey. Thus, unfortunately, it is not a question of devising a programme which will give the regular data that are needed, but of attempting to obtain the necessary information with resources which will almost inevitably prove to be inadequate. Yet, with the knowledge we now possess and the new methods which have been evolved, it is certain that very valuable results could be achieved by a comprehensive study of the fluctuations in the hydrography and plankton, and the work that is now beginning in the western Atlantic will lose much of its value if we are unable to obtain comparable data in our own waters. Before concluding this address I feel I should call attention to the urgent need throughout a very large part of the British Empire for greater activity in the scientific administration of the fisheries, for to me at least it is apparent that the lessons which long years of experience have taught us in this country are not generally understood elsewhere. The plain fact is that in the Empire as a whole we are deplorably deficient in fisheries administration. To this broad statement there are of course some exceptions. By reason of its situation in Europe the Irish Free State is obviously one of them, and it has taken its full share in the progress that has been made during the present century. Another exception is Canada, where a vigorous fisheries service, with a competent scientific staff, has been at work for many years. Newfoundland, a country whose fisheries are of predominant importance, not long since suffered a shattering blow in the loss of the whole of its laboratory build- ings by fire, but it will recover from this disaster and we may hope that the work which had such a brilliantly successful beginning will shortly be resumed. Australia has now made a fresh start after the tragic loss of the Endeavour and has at last taken the wise step of founding a Common- wealth fishery department. ‘These are the high lights, and there are one or two colonies, such as the Straits Settlements and Ceylon, which give relief to what is otherwise a very sombre picture. In South Africa with its astonishingly rich fishing grounds and vast length of coast-line the fishery staff is utterly inadequate, and in India, where fisheries research has immense possibilities, there is apparently little hope that proper action will ever be taken. In India fisheries are what is known as a trans- ferred subject : that is to say they have been handed over by the central Government to the provincial administrations. The result is that some provinces may have a scientific staff of one, others have none at all, while Madras, which is much the most enterprising and publishes a Fisheries Bulletin, has three. In such conditions fishery work on any adequate 100 SECTIONAL ADDRESSES scale is clearly out of the question and it is not possible even to begin the acquisition of the fundamental knowledge that is essential to future progress. Japanese trawlers, taking advantage of the complete lack of development of the Indian off-shore fisheries, are now visiting the Bay of Bengal in increasing numbers, and there is perhaps a possibility that their activities will cause the Government of India to realise how back- ward they are in fishery administration. It is evident that little or nothing can be expected from one or two men working in isolation and that only an all-India service, with the esprit de corps that such a service would have, can be sufficient for India’s growing needs. It has taken more than a quarter of a century of intensive co-operative effort by most of the leading European nations to build up the information that we now possess of the fisheries round our coasts, and though with existing knowledge and the better methods that have been devised it might be possible to reach the same stage in a shorter time, the accumula- tion of the necessary facts must inevitably be a slow process. Adminis- trators are still prone to expect a rapid solution to any question which they submit to scientific inquiry; but in almost every problem which touches marine biology it is essential to possess a background of funda- mental knowledge which can only be acquired by long years of patient study. If there is one lesson to be learnt from the history of fisheries research—one that cannot be too heavily stressed—it is that the oppor- tunity of dealing effectively with a fishery problem will generally be lost unless this basic knowledge has been obtained in advance and is ready for application. I-ven in our home waters, which have been examined so long and so closely, our information is not within sight of being complete: in almost every branch of fisheries work there are new fields to be explored, new methods to be tried, and many large gaps in the knowledge we possess. But it may at least be said that we have made a beginning, that we are aware of the deficiencies and are trying with the facilities we possess to make improvements. In many other parts of the world, however, not even a beginning has yet been made; ignorance is profound and there is no background of knowledge which can be utilised. It is no great exaggeration to say that in Africa and throughout almost the whole of the vast stretch of the Indo- Pacific region there is scarcely a fish whose life history is fully known and whose various stages from egg to adult can be recognised. Of such matters as age, rate of growth, spawning periods, food and migrations we are equally ignorant, nothing is known of the incidence of fluctuations and nothing of the seasonal or other changes in the environment. It is surely time that the importance of such knowledge was recognised and that early steps were taken to lay the foundations of fishery science throughout the Empire. When speaking of long-range fluctuations I expressed the view that the facilities we at present possess in Europe are insufficient to give us all the data we need: regular observations over a much extended area are required if we are to reap the full advantages of the knowledge we have gained. In the present state of international politics we can expect little ; but when, in God’s good time, the nations begin to turn their armaments D.—ZOOLOGY IOI to better uses, and the mass production of ploughshares begins, let us hope it will not be forgotten that there is also a harvest of the sea. REFERENCES. Berg, L.S. 1935 Zoogeographica, 3, I-15. Carruthers, J. N. 1935 Min. Agric. Fisheries, Fishery Invest., ser. II, XIV, 15, 16, Table VI. Cooper, L.H. N. 1938 Journ. Marine Biol. Assoc. 28 (in press). Farran, G. P. 1937 Journ. Dept. Agriculture for Iveland, 34, no. 2. Ford, E. 1933 Journ. Marine Biol. Assoc., 19, 373. Hardy, A. C. 1923 Publications de Circonstance, no. 78. Harvey, H. W. 1925 Conseil Internat. Rapp. et Proc.-Verb. des Réunions, XXXVII, Rapp. Atlantique, 1924, 82-4. 1930 Journ. Marine Biol. Assoc., 16, 791. —————— __ 1934 Journ. Marine Biol. Assoc., 19, 737. Iselin, C.O’D. 1938 Nature, 141, 772. Iverson, T. 1934 Rep. Norwegian Fishery and Marine Invest., 4, no. 8. Jenson, S.,and Hansen, P.M. 1931 Conseil Internat. Rapp. et Proc.-Verb. des Réunions, 72, 1-41. Lumby, J. R. 1923 Publications de Circonstance, no. 80. ———— 1925 Min. Agric. Fisheries, Fish. Invest., ser. 2, VII, no. 7, 18, fig. ix. Matthews, D. J. 1905 Internat. Invest. Mar. Biol. Assoc., Rep. I. ———————— 1907 Internat. Invest. Mar. Biol. Assoc., Rep. II, part 1. 1909 Internat. Invest. Mar. Biol. Assoc., Rep. II, part 2. tg11_ Internat. Invest. Mar. Biol. Assoc., Rep. III. —————_————— 1914 Fisheries, Ireland, Sci. Invest., 1913, iv. Russell, E.S. 1937 Biol. Reviews, 12, 324-5. Russell, F.S. 1930 Journ. Marine Biol. Assoc., 16, 707. ——— _ 1935a Journ. Marine Biol. Assoc., 20, 147. 1935b Journ. Marine Biol. Assoc., 20, 309. 1936a Journ. Marine Biol. Assoc., 20, 595. 1936b Conseil Internat. Rapp. et Proc.-Verb. des Réunions, 100, pt. 3, 9. 1936c Journ. Marine Biol. Assoc., 20, 507. 1937. Journ. Marine Biol. Assoc., 21, 679. ———— 1938 Journ. Marine Biol. Assoc., 22, 493. en B. 1934 Conseil Internat. Rapp. et Proc.-Verb. des Réunions, , no. I, 1-6. Stephen, A.C. 1938 Journ. Animal Ecology, 7, 125. SECTION E.—GEOGRAPHY. CORRELATIONS AND CULTURE A STUDY IN TECHNIQUE ADDRESS BY Pror. GRIFFITH TAYLOR, PRESIDENT OF THE SECTION. CONTENTS Geography and the Social Sciences. Geography and History. Evolution of Life and Culture. Relations of Culture and Race. General Ecological Approach to Problems in Culture. Correlations in the Distributions of Languages. Ecological Notes on the Aryan Problem. The Race of the Early Aryan-Speakers. Graphs of Culture Growth. Determinism v. Possibilism, in Canada and Europe. Culture in the Twentieth Century. Bibliography. HATH TOM OORD A. GEOGRAPHY AND THE SOCIAL SCIENCES. I mucu appreciate the honour of addressing the Geographical Section in my old Alma Mater, especially in this fine monument to the importance of Geography directed by my former sledge-mate, Prof. Debenham. Many presidential addresses have been devoted to a survey of the pro- gress made in one or another branch of our very varied discipline during the past twenty years. This is a safe and sane programme—but is not, I think, so likely to stimulate research as the unsafe and, as some would say, insane attempt to forecast somewhat of the advancement of Science in our special field during the next twenty years. There seems indeed something incongruous in a scientist from the Antipodes trying to say something new on the subject of culture amid these colleges renowned for their study of arts and letters. How can the experience of a geo- grapher, based on the study of contours, isobars, isotherms and all the other isopleths which adorn modern maps, help us to obtain a more valid interpretation of that elusive concept which we call culture? In my address I propose first of all to consider the field of cultural geography ; then to discuss a technique which I have found invaluable in research in that subject ; and finally to suggest that modern education would do well 104 SECTIONAL ADDRESSES to reduce greatly the study of certain fields of culture which were too strongly emphasised even in the Middle Ages, but which still occupy our young students to the exclusion of other far more important aspects of culture. Our field, fellow geographers, can, I believe, be made the most interest- ing in the realm of a general education. Partly because it deals with the vital facts of our environment ; partly because it is so comprehensive ; and partly because it is so objective. In these days of queer ideologies and freedom from canons, it should be all the more valuable that we, in our discipline, can chart our data and so make clear our problems, and in a sense prove our conclusions. At Chicago, one of the three leading universities in U.S.A., the whole of the various disciplines were grouped into the four divisions of Physical Sciences, Biological Sciences, Social Sciences, and Humanities. But there were a few Jiaison subjects which were too widespread in their interests to fit into any rigid division. Geography was one such subject, so that our large staff (and we had four full professors) was given a place on the Boards of both the Physical and Social Sciences. It is this feature of Geography which helps to give it a special place in a general education. If we look back at the relation of education to these four divisions of knowledge, we see a most interesting evolution. First of all, in the fourteenth century, the protagonists of the new Humanism waged a bitter fight against the Church and the Schoolmen. In the end the modernistic views of the humanists won, and we call this epoch the Renaissance. Next around 1600, the physical sciences were damned by the leaders of reaction, only to emerge triumphant in their turn. Some eighty years ago the biological sciences, in the persons of Darwin and Huxley, advanced truths which were anathema to the orthodox. Few educated folk attempt to oppose these truths now. But to-day the social sciences are challenged by the forces of reaction. I will only instance the perverted use of anthropology and sociology to advance the views of some of the totalitarian nations. We geographers can do yeomen service, as I see it, to clarify some of these issues if we teach tolerantly and scientifically what is becoming known as Cultural Geography. I could talk for half an hour on the question of the field of geography and yet not make my meaning so intelligible as the impression you will gain from the study of Fig. 1 for a few minutes. The diagram suggests that the field of geography (the large circle) contains eight subdivisions which in turn are linked with eight major disciplines (Griffith Taylor 1937). ‘Thus geography links the four ‘ environmental sciences’ of Geology, Physics, Astronomy, Botany, with the four ‘ human sciences ’ of History, Anthropology, Sociology and Economics. There are vast uncharted areas on the borders of regional geography—the core of our discipline—which merge into the eight subjects specified. Among pro- fessional geographers the great majority will always carry on the vital work in the central fields—but we may always hope for Raleighs, Drakes, Hawkins, and Dampiers, who will explore far afield and extend our realms. They will perchance trespass on other empires; and doubtless some conservative historians and anthropologists will call them buccaneers or pirates. Dropping metaphor, I firmly believe that by applying —_—— "> E.—GEOGRAPHY 105 techniques learnt in the realms of geography, biology and geology—and carried across to anthropology, history and sociology—such pioneers will ultimately earn the respect of the leaders in the ‘ purer ’ social sciences, But I must caution any piratical young geographer who cruises in strange waters that his reward, if any, will probably be a posthumous one. It seems advisable to consider for a moment definitions of the fields of geography. Like many other geographers, I have put forth my own definition, and it runs somewhat as follows, ‘ Geography is concerned with description, localisation and explanation of the data which relate man to his material environment.’ As I see it, the essential feature is the Jocalisa- tion (i.e. charting of the data in question) with a view to explaining their distribution. In a word we should make maps not solely as an Fic. 1.—The Liaison Character of Geography, using ‘Environmental’ Sciences to explain Social Sciences. The map of the continents suggests the ecological character of Geography. end in themselves, but with a view to explaining the phenomena in question (Griffith Taylor 1935). Perhaps, before proceeding farther, some apology is necessary for the introduction of so many diagrams into a presidential address. My excuse is that my subject is Geography— and Geography without maps is, to my mind, as little worth while as Hamlet without the Prince. B. GEOGRAPHY AND HIsTory. Let us now consider how the techniques of geography and allied sciences can be usefully employed in helping the social sciences. There are, of course, many ways in which charting data is helpful to the historian or anthropologist, but curiously enough many workers in the sister disciplines are extremely sceptical of the value of such a technique. I cannot do E2 106 SECTIONAL ADDRESSES better than quote a paragraph from a recent paper by my good friend Ellsworth Huntington on this very topic (Huntington 1937). ‘The majority of historians feel that they need a knowledge of geography. ‘Therefore, those among them who belong to what we may call the standard group devote an early chapter to a somewhat elementary but accurate account of the geography of their selected region, and then forget about it. Many historians are conscious that the Alps are really a barrier, and that the climate of Russia as well as of India is different from that of Belgium. Nevertheless, taking their work as a whole, an astonishing number of historians seem to regard a court intrigue as more important than the influence of climate, relief, occupations, and so forth, upon national character, or upon specific historical situations. This is not the fault of the historians. ‘The fault lies simply in the fact that both history and geography are still in a very crude state of development.’ ‘The route to a higher development has been explored a little by the economic historians. According to their view, man’s need of food, clothing, shelter, and the other good things of life, has been the keynote of history. Like the standard historians they have done yeoman service, and no word here said should be interpreted as dis- paragement. Yet many of them seem to have little knowledge of the way in which geographic environment influences not only the available resources, but man’s desires, and the degree of energy with which he works to satisfy them. . . . These differences arise in part from the geographical environment as well as from the historical development of a culture. Their effect on economic conditions and historical events is profound.’ I am reminded of a recent congress of historians in which I heard one of the chief speakers hold up to ridicule the idea that certain historical sequences in Scotland could be correlated with the Old Red Sandstone. From the applause, his fellow-historians agreed with him. ‘To the present speaker nothing is more likely than that such a relation existed; and indeed I propose to show one or two examples of the same type. The first example is taken from the finest collection of diaison studies in English with which I am acquainted. Here the various periods of English history are treated as separate stages of growth ; in each of which the effect of the environment on man is shown to be as important as it is to-day. I refer to the Historical Geography of Britain, edited by H. C. Darby. Here is history of an unusually valuable type; and it is food for thought that the authors are, as far as I know, all geographers. Is it going too far to say that most historians have felt so little need to study physical correlations that such a work could not be presented by them ? No historian would deny the vast importance of the wool trade in the fourteenth century. We owe to Dr. Pelham a map of the Sussex Weald (Fig. 2) which shows clearly how closely this trade depended on a geo- logical condition—the outcrop of the Cretaceous Chalk. I do not assert that this is the most vital feature of the wool trade in this period—but it did determine the site, which no historian can ignore. Another example from America explains a peculiar and characteristic E.—GEOGRAPHY 107 culture-complex in the State of Kentucky. Everyone has heard of the Blue-Grass Country around Lexington, and its association with horses and racing. It is rather sharply marked off from neighbouring areas, and its site is exactly determined by the geological structure (Fig. 3). The Blue Grass Region is an ‘ Eroded Dome’ much like the Weald. Here the fertile Trenton formation (of upper Ordovician age) is surrounded by rather sterile Carboniferous rocks. A similar eroded dome surrounds Fic. 2.—The Wool Industry in Sussex about 1350, determined by the Chalk Cuesta of the South Downs (based on R. A. Pelham). The black squares represent from 500 to 1,000 sheep in a parish. Na y\ a) Fic. 3.—Correlations between Geology (Eroded Domes) and Horse-breeding in U.S.A. Figures indicate approximately ‘ Horses per square mile.’ Nashville to the south. In Fig. 3, I show the close correlation between the Ordovician beds and the density of horses in these regions of Kentucky and Tennessee (Finch and Baker 1917). Such comparisons show how the geographer can help the historian to elucidate culture in almost any district in which he may be interested. Few students seem to have made use of graphical methods in investi- gating their historical problems. ‘These are, of course, the chief charac- teristic of geographical research. Especially is this true in regard to the use of Isopleths (lines of equal abundance), which can be applied to cultural 108 SECTIONAL ADDRESSES facts, almost as readily as to such features as temperature or elevation. In Fig. 4, a number of isopleths illustrating the spread of the Renaissance are charted. In diagram I some of the chief teachers of Renaissance ideas about 1350, such as Petrarch and Boccaccio, are localised. Later writers dealing with the ‘life of the times in living languages’ (a phrase which in part describes the Renaissance) were Wyclif, Froissart and Chaucer. Hence toward the end of the fourteenth century we see the new ideas moving north up the ‘ Way of Light.’ In diagram JJ (Fig. 4) I have stressed the spread of printing as perhaps the most characteristic feature of the second period of the Renaissance (1450 to 1550). Modern research (by J. H. Hessels and others) seems to refer the invention of movable type to Costar of Haarlem about 1446. It has spread to Mainz and the vicinity by 1460, moving along the ‘ Rhine-Way,’ and reached Rome by 1465 and Fic. 4.—The spread of Renaissance ideas in three stages, showing the effect of the ‘ Way of Light ’ and the ‘ Rhine Way.’ Paris by 1470. We have here an interesting example of a culture spread- ing along a new route, far removed from the familiar ‘ Way of Light.’ Other isopleths showing the rapid spread of printing throughout western Europe by 1480 are also charted. In the third diagram of Fig. 4, I have plotted the ‘ schools’ of the famous teachers in the third period of the Renaissance (1550 to 1650). Here I have not attempted to draw isopleths. But when I labelled each teacher as concerned either with science or letters, it was surprising to find that practically all the former were to be found in the eastern portion of the map, and all the latter in the western part. This is an interesting distribution which is in part no doubt associated with the leading religions of the two areas. The conservative west held by the old Catholic faith for the most part, while the eastern region was that where the reformed religion had the chief control. This distinction in turn is of course bound up with the deep-seated inheritance of Roman culture in France and Italy, which was wanting east of the Rhine. The votaries of mediaeval science were not encouraged by the orthodox Roman Catholic Church, so that naturally they were not numerous in the western part of diagram JJI. In the social sciences, we are dealing with disciplines of an intermediate character. In much of their content, they are not so susceptible to rigorous proof as are many of the problems in the physical sciences, and in this they resemble the humanities. But like the latter they have the E.—GEOGRAPHY 109 great educational advantage that they deal definitely with man rather than with lower forms of life or with physical phenomena. A disadvantage inherent in geography and allied subjects is the immense number of facts whose assimilation would seem to be necessary in the study. This is wearisome in a scheme making for an all-round education, and in my opinion memorising facts should never be the vital factor in geography. You may have heard of the despondent negro preacher who complained that his flock was either so ignorant that they believed too much in ‘ de deuce,’ or so sophisticated that they doubted everything. Students of cultural geography should also learn to ‘ doubt and deduce,’ rather than to memorise the innumerable facts often presented without coordination. It is this training in deduction, accompanied by a healthy scepticism of orthodox dogmas until they have been tested and confirmed, which should be our aim. C1. Evo.LuTion or LIFE AND CULTURE. To the geographer interested in culture-spreads, it seems likely that the one outstanding fact has often been neglected by sociologists. It should be clear that as long as man was controlled primarily by the same factors as the higher mammals his evolution is likely to proceed along somewhat similar lines. We shall find in many fields of research that we are dealing with the same phenomena, i.e. with progressive stages of evolution developing in the Old World ‘ cradle.’ This concept can be illustrated in Mammals, Human Race and Human Culture alike. Matthew has shown that the cradleland and stages of evolution for various related groups of the higher mammals can be deduced wholly from their distribution in time and space (Matthew 1915). In Fig. 5 at B, I have summarised his conclusions in a block diagram, which shows that we are dealing with a typical example of what I describe later as the ‘Zones and Strata’ phenomena. Here is illustrated the problem of the vast biological changes involved in changing something like an antelope into a sheep. Needless to say millions of years have elapsed while this occurred. But the salient control was the marked environmental stimulus centred in south-central Asia. There is no reason to doubt that these special conditions continued to operate in this region from early Tertiary times up to the development of the first stable civilised communities of man—say, around 10,000 B.C. If we grant this postulate, then it would seem obvious that the variations in the Auman species (i.e. racial groups) would almost inevitably arise in the same region of great stimulus. ‘These might be expected to develop in a much shorter period, say of the order of half a million years. The writer has demonstrated this thesis in many books and papers. Finally, major culture-changes are also essentially responses to environ- ment—though far more rapid than biological changes. There is, to the writer, no region more likely than south central Asia where the tremendous development from the nomadic hunter to settled village- dweller was so likely to occur. I pointed out this inherent geographical advantage nearly twenty years ago; and since that time I have watched the students of culture driven from Egypt to Mesopotamia, and finally to IIo SECTIONAL ADDRESSES some, still indefinite, region to the north in their efforts to find the cradle of civilisation. (I shall return to this aspect of the subject later.) Thus we arrive at the interesting result that major racial evolution and major cultural evolution occurred in much the same region; in spite of the fact—often pointed out—that there is no inherent connection between a given race and a culture associated with it. The time-factor is very different in the two phenomena. In the field of Race, during the short period of the recent centuries, we have only seen the origin of a few hybrid groups, all unimportant except perhaps for the Mestizos of Latin America. But we have observed new cultures travel all over the world ; their speed of expansion increasing with every passing year. Thus tobacco spread far and wide within a century after Raleigh brought it to Europe. Nowadays the son of the head-hunting Papuan delights to drive a motor launch, and the second generation from the cannibal Fijian is filling the medical services in those tropic isles. C 2. GENERAL DiscussION OF THE ZONES AND STRATA THEORY. It was his use (on world maps) of the isopleth method in charting the criteria of race, in conjunction with the findings in W. D. Matthew’s memoir ‘ Climate and Evolution,’ which led the writer to publish the “ Zones and Strata Classification of Races’ in 1919. The general principles of this concept are illustrated in Fig. 5. Here three parallel cases of Fic. 5.—Block Diagrams illustrating the ‘Zones and Strata’ Concept applied to Culture (Evolution of Transport); Mammals (Artio-dactyls); and Major Races. In each case the centre of evolution is in the centre of the zones, and the most primitive types have been thrust to the margins. The strata appear on the vertical edges (at right). All much generalised. evolution are considered. All anthropologists-will agree as to the explana- tion of the block diagram on the left. Here we see zones of Methods of Transport (ox-team, horse-bus, motor-car and aeroplane) arranged round the city of Sydney—the only settlement of note for sixty years in Australia, The “ strata ’ resulting from this evolution in Sydney and gradual migration | to margin, are indicated on the vertical edge of the block diagram. Clearly there is a common cradleland, where commercial activity is greatest in the centre of the zones—and the primitive types now occur precisely where they did not originate. E—GEOGRAPHY Ill Turning to Fig. 5 B, we find the same process illustrated in the evolu- tion of the Artio-dactyls (or even-toed mammals) based on data given by Matthew (1915). The antelopes are earliest and are displaced farthest from the centre. The sheep are latest and still characterise the common cradleland. The fossil strata are in accord, using the palzontologist’s ‘ Law of Superposition.’ No biologist doubts that the zones and strata in the case of these mammals indicate the order of migration and of evolution for the Artio-dactyls. The writer believes that primitive man was differentiated into the five major races long before the later races reached Western Europe. This evolution almost certainly took place in Asia and occurred before the last Ice Age. It certainly far antedated early Neolithic times.‘ Hence early man of such a primitive type can surely be considered as obeying the same laws of migration as the higher mammals. If now the pre-Columbian distribution of the major races (Negro, Mediterranean and Alpine) be plotted in a block diagram (Fig. 5 C), we find a series of zones and strata closely resembling the two already charted. It is difficult to escape from the conclusion that the centre of Asia is the common cradleland where evolution progressed most actively in the case of primitive man—just as Matthew has shown it progressed most actively here to produce new types of the earlier mammals. Indeed, we can almost exactly parallel the spread of the rhinoceros from Asia with the spread of the negroes, while the spread of the Pleistocene Equidae is the same as that of Alpine man (Matthew, Figs. 20 and 17). The centre of stimulus in Fig. 5 A was the commercial progress in the city. In the case of the mammals and man it was the stimulating climate of south central Asia. I have shown in a number of books and papers (see bibliography) that this region in the past has been characterised to a marked degree by such climatic features, but lack of space prevents my covering this ground again. C 3. CORRIDORS INTO THE CONTINENT. It is of considerable interest to use our knowledge of the relative accessibility of the other continents from Central Asia, and to see how the consequent migrations agree with the ‘ Zones and Strata ’ hypothesis. Most anthropologists accept Asia as the cradleland of the later, i.e. the Alpine, Mediterranean and Australoid, Races. If we are to assume that the earlier negroes or negritoes evolved in Africa, then we are faced with several cumbrous inconsistencies. Where did the negroes (and negritoes) of Melanesia and thereabouts come from? If Africa is suggested, the obvious reply is that it is far simpler to assume that both African and Melanesian negroes come from south Asia, i.e. the same centre of racial evolution as did the other races. Moreover, the ‘ Zones and Strata’ hypo- thesis leads us to believe (even if this be not actually proven) that primitive races persist in the marginal lands, precisely where they did mot evolve. 1 It is probable that the first Alpine peoples reached France (Solutré, etc.) in Aurignacian times (vide A. Keith) ; and Koeppen dates this as far back as 74,000 years ago. Neolithic times in France were only 8,000 years ago (Keith 1931 and Koeppen 1932). 112 SECTIONAL ADDRESSES The same arguments apply to the negritoes, and lead us to accept an Asiatic cradleland. What was the relation of Africa, Australasia, and America to the Eurasian land-mass during the later Ice Ages—when we may surely picture these earlier racial migrations as occurring? Surely something like this. The easiest of access was Africa, for only the Red Sea— probably much less of a barrier then—separated that region of deserts and savannas from the South Asiatic cradleland. Australasia was the next most accessible. During the Ice Ages no doubt the broad low area of Sunda Land with the almost dry Bali-Timor ridge led man to the large low ‘ Sahul Land’ and so to Australia (Griffith Taylor 1937). Inthe Interglacial period both Sunda Land and Sahul Land were drowned as the result of the filling of the oceans by the melting ice caps. Hence we may postulate that Australia and Melanesia were, on the whole, much harder to reach than was Africa in those early days. As regards America, all migrations must pass va north-east Siberia. In the Ice Ages this was covered with an ice cap (Griffith Taylor 1930) which would definitely discourage migrations. During inter-glacials the Behring route might be quite feasible—and doubtless during such a period a few tribes of Australoids or kindred folks reached America. Possibly during the close of the Wurm Ice Age the Eskimo reached America while their congeners, late Paleolithic man, were reaching Western Europe. The main migrations into America seem to have occurred in the warmer periods (say of the Achen retreat of the ice, or between the Buhl and Gschnitz minor advances of the ice in Europe) some ten to twenty thousand years ago. Now, assuming these geographical relations, what should we expect to find? Primitive man was thrust out of south central Asia (primarily by climatic changes leading to greater cold or aridity) and would know nothing of the outlying areas. He would, no doubt, move off in several directions (to south, south-west or south-east) more or less equally. Thus the greater proportion of the earliest (Negro) migrations would inevitably reach Africa (the easiest outlet, on the whole), while a smaller number would reach Melanesia by circumventing the very difficult tangle of mountains in south-east Asia and crossing the ‘ stepping stones’ of the East Indies ; and, if fortunate enough, making use of the alternately open and drowned corridors of Sunda and Sahul Lands. This ‘ paired ’ dispersion to west and east is illustrated in Fig. 7. As millennia passed the more accessible lands of Africa would fill up, and Australia would receive a much larger proportion of later (Australoid) migrations. Finally as the latest migrants were thrust from Asia, the American corridor became available—and this is why we find so large a proportion of the last or Alpine-Mongolian Race in the New World. A glance at the arrangement of the zones (Fig. 7) will show that this series of migrations is fully corroborated. C 4. SCANDINAVIAN CLIMATE. Let us now consider the environmental conditions somewhat more in detail. In the first place the migrations were probably extremely slow, E.—GEOGRAPHY 113 and were made quite unwittingly by the primitive peoples concerned. They would all be hunters, preying on wild animals or upon wild fruits and grains. With the onset of any Ice Age, the forests, steppes, and tundras move slowly but en masse to the south. A fall of temperature of 12° F. is the maximum effect. This temperature range (by the ordinary ratio explained in any text-book of climatology) ? is normally equivalent to a journey of some 800 miles toward the Pole. Such a migration of vegetation would perhaps change half the Siberian forest into tundra, and change the whole central Asiatic desert belt into steppe, while much of the southern forest belt would gradually turn into desert. Research in Scandinavia has made it much easier for us to reconstruct Fic. 6.—Correlations of Climate and Culture, showing the Northward March of the Ice-Cap, the Vegetation Zones and Primitive Man in Scandinavia since the close of the Wurm Ice Age. The front of each diagram shows the Strata in section. the movement of ice-caps, vegetation-zones, and of man himself (Griffith Taylor 1934). De Geer and others working on the Varve-clays have dated the moraine of the waning Wurm Ice Age as it developed in South Sweden. They place it about 18,500 B.c. This is shown in Fig. 6, at A, where Sweden is shown buried under the great ice-cap. Peat bogs in North Germany and Denmark show that tundra plants were growing south of the ice-cap at this time. Man had apparently not yet appeared in Sweden. In block-diagram B (Fig. 6) we see that the ice-front has retreated northward half-way along the Swedish Peninsula. This is dated about gooo B.c. At that time the peat bogs in Germany show remains of fir-trees, and here also we find the artefacts of Neolithic man. Apparently Palaeolithic man found the tundra and steppe very unattractive and so never settled on the Baltic. The next diagram C shows us a further retreat during 5,000 years. The fir now covers Southern Scandinavia 2 Off China the world isotherms change 1° F. for about 1 degree of latitude. SECTIONAL ADDRESSES 114 (‘LE61 ‘p10}xy ‘UONDASLIY PUY BIDY “JUcemuUoALAUT WoOIy dewl pPastAdy) ‘WoOlyNJOAD JO JepioO pue PU[E]peIO UOWMIOD INEY} 07 anjo ay} sears AZo[Ooy = ~py1om oy 39A0 Te peoids pey o ‘a'v jnoqe seovi JofeuI say oY, oJ ‘Tey ‘xepul peoy . uo se [Jam se sodioutid yeorsojooa pue A10}sTY ]VIORI UO posed ‘URI JO S9DEY OY} JO UOI}EOUIsse]O [eoIso] oy. —ZL “DIT Pei ae SE Te OLIN NEW SO SIDYAY A Yl ll) ——O2°3N Hit 10 ERE re NOILYASWSSY 7D 5 Wer IMIS TY ATH ANOZ —NOlLE ODN GLEALS SO FICHO E.—_GEOGRAPHY 115 and oak-trees cover North Germany. Bronze tools are found in the bogs in the oak stratum—showing that a higher culture has moved north with the ice-retreat. Finally, at the dawn of history, conditions were like those to-day. The beech is now the dominant tree on the Baltic— and its advent was marked by the coming of Iron Age man. Here, then, we have a dated set of zones and strata, and we can be sure that similar movements of vegetation and man, northward and southward, accom- panied every one of the Ice Ages throughout the Pleistocene. The general distribution of Races over the World, before the period of modern marine migrations, is given in Fig. 7. I have devoted nearly twenty years to this ‘ Migration-Zone’ theory of racial evolution and classification, the main features of human ecology. I mention it here primarily because it demonstrates that all the progressive nations of the world are built up of the same three stocks, ‘Alpine, Nordic and Mediter- ranean.’ When this thesis is accepted, then much of the evil structure based on ‘ race-prejudice ’ must fall to the ground. In my opinion, race prejudice is but another name for ethnological ignorance. This is a very encouraging idea, for cultural differences of language, education and religion can be entirely changed in a generation, whereas a real racial barrier is much more difficult to overcome. ‘Thus the world must wait a long while for the negro problem (based on a real racial difference) to be solved. But racial differences exactly like those separat- ing Europeans, Japanese, Chinese, Indian, Polynesians and Amerinds have all been smoothed away in Europe itself; where (in my opinion) their component stocks came into contact with each other long ago in Neolithic times. D. RELATIONS OF CULTURE AND RACE. One of the main results of a knowledge of cultural geography is a much clearer conception of the distinctions between race, nation, language and religion than most educated people possess. It can be well illustrated, as we shall see, by maps in connection with the spread of the Jewish people. Moreover, this study clearly defines the danger resulting from powerful political groups dabbling in sciences of which they are ignorant. We are surely all agreed that the term Aryan can only be applied to speech; and that Nordic indicates a ‘breed’ and can only be applied to race. But few folk realise that the term ‘ Jew’ should only be used in connection with religion. It is much too common an experience to have to argue with folk, however influential, who insist on talking of a ‘ Jewish Race.’ We need a new term to express a group linked by purely cultural characters such as language or religion. For such groups I have been extending the use of the word ‘ cult.’ For instance, in Canada, we have in reality no ‘ French Race’ (since Frenchmen may belong to one of three distinct races), but only a ‘ French cult ’ linked by common language and religion. So also we should learn to speak of a ‘ Jewish cult,’ since this large group is linked closely by religion and to a lesser degree by language. The Jews, like the Germans, are of two different races. If they come from Poland they belong to the Alpine race; if from Spain they are of Mediterranean race, like all the original Jews of Palestine. 116 SECTIONAL ADDRESSES Since this problem illustrates very concretely the way in which the social sciences are vitally concerned in world politics, I will dwell on it briefly. It is illustrated in the two maps in Fig. 8. On the left we see the logical linguistic divisions in Europe, which are undoubtedly Aryan and Altaic. Here also is shown in black the realm of the German nation. In the right-hand map (Fig. 8) are the race divisions in Europe, i.e. Nordic, Alpine and Mediterranean. The German nation is half Nordic and half Alpine. The Jew belongs to a ‘ cult,’ but the dominant Jews in Europe, including about three-quarters of the whole body, are broad- headed Alpines like the rest of the mid-European peoples. The most logical explanation is that the Polish Jews are the result of the widespread conversions carried on by the Jews in eastern Europe. For instance, in A.D. 740 the Khan of the Khazars (who lived north of the Black Sea) was converted, and many of this large nation of medieval traders ZZBOvER 15°F 1-15 % Fic. 8.—(a) Map of Europe showing the distribution of Aryan and non-Aryan (i.e. Altaic) Languages. The area of the German Nation is also charted. (b) Map of Europe showing the distribution of the Nordic Race (dotted), and of the folk who profess the Jewish Religion. The Alpine and Mediter- ranean Races (M) are also indicated. followed his lead (Griffith Taylor 1936b). Racially the Khazars were akin to the Turks, i.e. they were Alpines; and they are also known as the Royal Scythians. Indeed the Polish Jews still call themselves Ashkenazim, which is a Hebrew word meaning ‘ Scythian.’ A year or two ago the German authorities were specifically excluding the German Jews as of ‘non-Aryan race.’ Of course racially they are Alpines like the south Germans, and their language is best called Judeo- German. Anyone with a slight knowledge of German can understand the following sentence ‘ Es ist gar alles kein Neues nicht unter der Sunn.’ Yet this is Yiddish, which is mostly a medieval German dialect learnt in the Rhineland (Wiener 1899). It has a considerable addition of Hebrew words, in the same way that English includes much Latin, but English does not thereby become a Romance language.. Nor does English change its Saxon character when it is written in Pitman’s short- hand. The Semitic script used in Jewish newspapers disguises, but does not change, the essentially Aryan basis of Yiddish. Thus the accurate student of social science would describe the Jews as a composite’ culture-group (‘cult’) with a specific religion, most of whom are Alpine in race, and speak an Aryan language (a dialect of German) which is written in a peculiar script. E.—_GEOGRAPHY 117 E. GENERAL EcoLocicaL APPROACH TO PROBLEMS IN CULTURE. Let us see how ecology can help the study of the evolution of languages. The early settlers of New England came mainly from Suffolk and the adjacent south-east of England. They carried to America the pro- nunciations of early Stuart times, and some of these have changed con- siderably in England since their departure. In the fifteenth century words like dark, far, farm, star, etc. were spelled and sounded derk, fer, ster, etc. So also clerk and new were pronounced clerk and noo in this part of England. About the time of Elizabeth the pronunciations clark and nico were growing in favour, and have since become universal in England. The older forms were carried to America and survive in rustic New England. So also certain Elizabethan and Stuart ballads are perhaps better preserved in the isolated mountain hamlets of the Appalachians than in most of England. Many old words have become archaic in England which are still in common use in much of America (Wyld 1920). MMM ST sii 1 aS Com PRON: ,¢ 00 COOMA) avo avec ner sens Oo ARCHRISMS Fic. 9.—Linguistic Evolution indicated by the distribution of early pronuncia- tions and folk-lore, which survive in marginal regions. An illustration of the ‘Zones and Strata Concept.’ Three ‘strata’ are suggested on the front edge. Examples are fall (autumn), guess (think), sidewalk, whittle, greenhorn, cordwood, gotten, cracker (biscuit), shoat, etc. Here again, as we saw in race, the primitive is ‘ pushed to the wall’ far from the cradleland. No one imagines that Shakespeare lived in the Appalachians because some of his language is now perhaps more common there than at Stratford ! But many philologists have thought that Sanskrit originated in Lithuania ; whereas Lithuanian is a marginal survival of an early Aryan akin to Sanskrit, thrust out from the common cradleland in south central Asia. These stages in the evolution of the details of a language are charted in Fig. 9 which illustrates the principle of the ‘ Zones and Strata Concept ’ fairly clearly. As before, we see that the primitive type is pushed to the margin, while the later types appear first in the central cradleland. Of course conditions have changed so greatly in America in the last fifty years that it is now an independent centre of stimulus—possibly the greatest in the world in regard to modern culture—and Britain is borrow- ing new terms from the U.S.A. There is, however, not much difficulty in detecting such new centres of culture in dealing with problems of the evolution of early culture in the Eur-Asian world. For the most part they progressed fairly regularly from south-east to north-west. This is indicated in the following graph dealing in a general fashion with certain phases of progress in the last 6,000 years. 118 SECTIONAL ADDRESSES This diagram (Fig. 10) illustrates the necessity for defining the amount of correlation involved in a given comparison. It is, of course, obvious that the shift of power is not wholly determined by the lower temperature of high latitudes. There is, however, no doubt that physical vigour is somewhat higher at lower temperatures, though Huntington is convinced that the optimum occurs at 63° F.; while the best mental work is done in regions with an average temperature near 45° F. (Huntington 1938). These facts must have a bearing on the evolution of all forms of culture. Probably of equal importance in the shift of empire are other factors such as ‘ freedom from invasions.’ Invaders attacked Europe from Asia and Africa at first; and later, Britain was saved by her insular position from many continental attacks. Command of the Atlantic seaboard, and, chief of all, readily accessible coal supplies also contributed to this shift to the north-west. We may use as an illustration of the value of the ‘ Zones and Strata Concept’ that complex of races and cultures which characterises the Sane ( Macedonian ee ay Le le man oe a PR X sD as Fic. 10.—Correlations of Temperature and Empire. Other factors are discussed in the text. Indian and Pacific areas. ‘The writer has had the advantage of travelling widely in Eastern Asia and in the Pacific, and this has focused his atten- tion on the general principles underlying dispersion in this area. It is quite obvious that every widespread characteristic in Polynesia has migrated from west to east—and that any cultural contacts with America can be completely ignored in a general study. Let us examine the data in Easter Island—the farthest of these isolated groups from Asia (Fig. 11). It is almost 14,000 miles from the Caspian area to Easter Island, yet I hope to demonstrate a culture sequence stretching across all this vast expanse. Two remarkable features in Easter Island are the well-known stone statues and the undeciphered script incised on wooden tablets. There is no reasonable doubt (as the Routledges (1919) have shown) that the statues, with their bird-man decorations, are of the same culture-complex as is common in the Solomon Islands, some six thousand miles to the west (Fig. 11). Hevesy (1933) and Hunter (1934) are satisfied that the script, the only one used by Polynesians, is connected with the remarkable Mohenjo Culture which flourished in the Indus region about 3000 B.c. It is true that objections have been raised by Métraux (1938) that the script was not understood by any living Polynesian, and that the tablets of mimosa wood, etc., are not likely to be many centuries old, some indeed being E.—_GEOGRAPHY 119 modern in origin. The present writer thinks that these objections are not very relevant. Our own alphabet is said to originate from not very similar signs used by miners in Sinai, though all the links are not yet clear. The question surely is to determine the origins of the remarkable Easter script—and to my mind, the Mohenjo theory is plausible and indeed probable. Moreover it offers a good illustration of clues which may be furnished by an ecological approach. Let us consider some of the major culture changes in the Indus region. Gordon Childe (1934) gives data as to the races which have been discovered at Mohenjo. Australoids, Mediterranean, Armenoids and Mongoloids were all present. There can be little doubt that the first settlers (before 3000 B.C.) were the aboriginal ‘ Australoids’ who spoke a Munda language. Many members of this zone of peoples are now found ‘ pushed to the margin’ in the East Indies and in Australia. It is represented by =aoomans oS ee Balj | SO oH ENIO age coee + EE 5 |Bc soo |. Boo MAIN CRADLE oF CULTURE S| 5 tbeey “2 25° Fic. 11.—The spread of cultures from India eastward; showing the Munda, Australoid culture at the bottom, covered by Dravidian, Polynesian, Aryan- Buddhist and Moslem ‘strata.’ In the Inset are compared some signs from the Mohenjo and Easter Island scripts. All much generalised. Stratum 1 in Fig. 11. The general belief is that the Mohenjo culture was due to the later ‘ Mediterranean’ races who spoke Dravidian lan- guages. ‘This constitutes Stratum 2, and in the writer’s opinion is to be linked with Dixon’s ‘ Caspian Race’ in the Polynesian area (Dixon 1923). We have little knowledge of the period from 2500 B.C. to 1500 B.C. in India, when the great Aryan migrations overwhelmed North India. But it is significant that the earliest stone monuments in India, which are found at Rajagrha (Rajgir) near Patna,® are of a cyclopean character quite unlike the work of the later Aryan builders, and rather resemble the mysterious early stone monuments of the Pacific (Fergusson and Burgess 1880). I have suggested that this culture-complex spread out as Stratum 3. The Aryan-Sanskrit complex (Stratum 4) never reached Polynesia, but was carried to Java and dominated that region for several centuries after 200 B.c. In North India Buddhism (Stratum 5) flourished after 500 B.c. 3 The Jarasandha monument (of unknown date) is a square truncated pyramid 85 ft. wide and 28 ft. high. It is built of large uncemented blocks of stone 5 or 6 ft. across. It resembles the truncated pyramids and Mare of Polynesia. 120 SECTIONAL ADDRESSES and was carried to Java about the eighth or ninth century of our era. It did not displace the older Hindu pantheism—but flourished alongside. Around A.D. 1400 the Moslems (Stratum 6) conquered Java, and the Indian religions found a refuge in the island of Bali further east, where they still flourish. It is not, of course, suggested that the Polynesians migrated from India, for they probably lived originally in south-east Asia. But their culture probably followed the same route as that used by the Buddhist and Moslem teachers in historic times. We may dwell for a few minutes on the recent discoveries in the vicinity of Persia. In Mesopotamia the earliest culture of Sumer is known as “al Ubaid ’ (Childe 1934), and this contained copper tools and is younger than cultures from Susa and the adjacent Persian Plateau. To the north near Nineveh is the ‘ Tell Halaff Culture ’ with wheeled vehicles, but with no metal. This is much older than anything dis- covered in Sumer near the Persian Gulf. Still older are the lowest cultures of Samarra in the same region, where they occur in debris seventy feet below a temple dated about 2450 B.c. Childe corroborates my statement (of 1919) as to the cradleland of man, with his comment that the early cultures of China resemble those of Anau in Turkestan (Fig. 11). It is significant that Zoroaster, the first great religious teacher, lived in this same vital region. ‘Thus we see that the centre of the zones of the races of man in Turkestan (as charted in Fig. 7) is also likely to be near the cradle of civilisation. F. CORRELATIONS IN THE DISTRIBUTIONS OF LANGUAGES. The evolution of nations is one of the most interesting and important problems engaging the attention of the social scientist. A common language is often the chief ‘ cement’ which links the various races and ‘cults’ to form a nation. Hence languages merit our careful study. Few problems in Science are so difficult as those concerning the inter- relations of the main language-groups. Since here we have to do with an evolving complex arising in something like a cradleland and affected by wide migrations, it seems likely that some light on the subject may be obtained by charting the data in the form of the ‘ Zones and Strata’ technique. The distribution of the main groups of languages is given in a generalised fashion in Fig. 12. The ecology of language indicates that the order of evolution in the Occidental area is in the following sense, the marginal languages being the earliest :—Bantu, Hamitic, Semitic, Basque, Su- merian, ‘K’ Aryan, ‘P’ Aryan, and latest or ‘Satem’ Aryan. The problem is, of course, complicated (as in -Biology) by the fact that independent evolution takes place after the branching of the parent languages. Thus it seems likely that Proto-Gothic branched off from the Aryan stock before Sanskrit. Yet English (a descendant of Proto- Gothic) is a more advanced language (i.e. more analytic, simpler and easier to learn) than is Sanskrit. E The following summary (Worrell 1927) gives simple definitions of the language classes. In primitive languages like Bantu, parts of speech were differentiated by the attachment of different relationship-words—which, 12! E.—_ GEOGRAPHY (‘1z61I ‘HIOX MON ‘mataaaz a1yGvasoay ay Woy) ‘souoz UoT}eIsTU [eIOAES ay} JO [eoIdA} sosensur] SUIZSIXO UMOYS 91e BOeFINS 9Y} UD ~WOT}eS UT Uses are ‘sonSuo} Suystxe apun poring ‘se8ensury qissoy ‘Aroydised ay} 0} yno sear] Snorasid 9y3 Jo ysour soysnd ‘mop snotaoid 943 Jo worjz10d aos SurTI9A09 aTTYM ‘pue 91}U90 oY} Wo sastie UoTWdnie Mou YORY “SUOTOOITP [Je Ul VAT JO SUTeOI}s Y}10F Surpues _uorjdnie oinssy , JO 10s & se painyord st eisy [e1}zUeD UT [TesiodsIp Jo oIyUE0 OY, “SOT}SINSUT] Pure WOTNJOAD Jo SaIpNyzs 07 poydde ASoyeue MOP-eAP] YL ‘“poestesoues ATYSty sty] ‘onbruyoa3 , e}e13S pue seuOZ , oy} Jo ‘Iz6I ut poysyqnd ‘uorzersnyt wy—zI “O17 ‘ anosba 122 SECTIONAL ADDRESSES however, did not fuse with them. Vowel harmony of all the syllables of such a compound often developed as a means of marking off the group. This is Agglutinative speech. It survives in the Bantu tongues (prefixing type) and in the Altaic (e.g. Turkish) as a suffix type. The Hamitic-Semitic group carried agglutination so far that the re- lationship-words fused at last with the chief words to which they were affixed or prefixed, and speech became amalgamating. Words were also systematically modified by internal vowel-change to give regular altera- tions of meaning. Dravidian speech is agglutinative—affixing and in- fixing, so that it is rather generalised and may be the ancestor of several of the other main languages. The Aryan group developed external suffixes to indicate variations, and so produced inflectional language. The three groups Hamitic, Semitic and Aryan also tend to rely on relationship-words and on word- order, and increasingly to neglect the word-forms. ‘Thus they become analytic. ‘There is little doubt in the writer’s mind that this sequence (e.g. from Bantu to such an Aryan language as Persian) represents lin- guistic evolution, in much the same sense as the sequence ‘ amoeba to man’ represents zoological evolution. In both cases many groups branch off from the main stem producing minor independent evolutionary groups. In both cases some descendants stagnate, while others advance rapidly, as stated earlier. Before Aryan scholars yield to despair because the foundations of Aryan are ‘wrop in mystery,’ a promising field would be to explore Dravidian or Altaic for the ancestors of the Aryan. For instance, there are three possible explanations for the accepted resemblances of Finn to Teutonic. The one usually accepted is that Finn has borrowed from Teutonic. But it is also possible that Teutonic has borrowed its ‘ pecu- liarities’ from Finn. A third view worth considering is that border (e.g. primitive) languages like Keltic or Teutonic, still retain speech characteristics which have been carried over from the more primitive speech (now preserved as a marginal language-zone) from which the Aryan group as a whole evolved. On this view the features common to German and Finn may be an inheritance from the common mother-tongue of Aryan and Altaic. The lesson to be derived from the ‘ Zones and Strata’ technique is that marginal languages should be compared with each other. This means that far-distant speeches may be very well worth comparing. From this point of view, we should actually expect that Basque would resemble some Amerind language ; that Gaelic would resemble Pharaoh’s tongue ; and that early Sinitic, early Altaic and early Dravidian (i.e. marginal languages) should be studied to learn something about Proto-Aryan. Thus the writer by no means despairs of the solution of the Aryan problem. These ideas have long been engaging the writer’s attention. In 1921 he published a generalised diagram, which was probably the first utilising _ the ‘ Zones and Strata Concept’ as applied to Linguistics. With a few minor alterations it is reproduced as Fig. 12. Here the concept of a central cradleland of culture is adopted. But we must ever bear in mind that we are primarily concerned with events which occurred before E.—GEOGRAPHY 123 5000 B.C., for all the major language families had differentiated before that period. The cradleland is represented as sending forth successive flows of lava from a centre of eruption. These form concentric zones about south central Asia, and each flow pushes its predecessor to the margin. The effect of one flow on its neighbour—involving some contact and assimila- tion—is also rather usefully indicated. The flows reach the four ‘ pen- insulas ’ of Asia (i.e. Europe, Africa, America and Australasia) according to the relative advantages of the connecting corridors. I have elaborated this concept in several essays already published (Griffith Taylor 1936c). G. EcoLocicaL NoTes ON THE ARYAN PROBLEM. We may use the stage-diagram to correlate our scanty knowledge as to the early wave-fronts of the Aryan languages. There are three fairly definite subdivisions of Aryan: (1) the early Kentum or ‘ K’ speeches like Gaelic and Latin, (2) the Intermediate ‘ P’ languages like Welsh (with which we may associate Teutonic and Greek for convenience), (3) the later Satem languages like Slav and Indian. _ Turning to Fig. 13, some idea of our knowledge of the language dis- tribution in Sumerian times is given in the lowest map of the series. At this time Hamitic languages were used by the Pharaohs in Egypt, akin to those still spoken by the Berbers in the Atlas Mountains. Semitic languages characterised Arabia and Syria, as they still do. Sumerian itself has some resemblances to the Altaic, though its affinities are not yet clearly understood. In Europe at this early date there were racial allies of the present-day Hamitic-speakers—all of Mediterranean race—living in the western regions, who probably spoke Hamitic according to Rhys and Jones (Griffith Taylor 1936a). Central Europe was occupied by early migration of Alpine ‘ Brakephs’ (broadheads), of whose language we know nothing. It was almost certainly not Aryan, and something akin to ‘ Basque’ seems most likely. This problem is taken up later. In view of the important corridor linking Turkestan with China by way of the Tarim Basin, I have ventured to suggest that a linguistic kinship between early Chinese (Sinitic) and Sumerian or early Aryan is only to be expected. In the second map (Fig. 13 at B), for the period around 1200 B.c., we are on surer ground. Vast migrations of ‘ Satem ’-speakers had poured into India from Turkestan. The Hittites, who seem to have spoken an Aryan tongue somewhat akin to the Kentum Group, were in control of Anatolia. Semitic was now the chief language of Egypt and Mesopotamia. In central Europe (if we adopt the suggestions of H. Peake) Kentum languages were spoken in the regions east of the Alps, while Brythonic (one of the Intermediate ‘ P ’ type) was that used by the Cimmerians of the Ukraine and Caucasus areas, It seems logical to assume that many Satem-speakers still remained in Turkestan, and were perhaps allied to the Sarmatian tribes. In the next map (for 400 B.C.) we see the first great Aryan conquest in the Near East, that of the Persians. They spoke a Satem language, and it is probable that their Sarmatian kin were occupying the European 124 SECTIONAL ADDRESSES RASSSY ASSALRATY TYAS Sa 9 fewer WAALS VAAN Oe NI LY (TTX i EBaene' SA NSS SSS ———E—E—EEEEE—ee eS C7 Le pea eeamea eRe os g ~ ~\ >>—=. CH; CH, CH, CHy co co COOH | COOH : : =r COOH COOH H.COOH pyruvic diketoadipic succinic malic sh formic Disappearance of malic acid is ascribed to its oxidation to oxalacetic acid, the conversion of this to pyruvic acid, and the breakdown of the latter on removal of the inhibitor of carboxylase. Bennet-Clark has pointed out a number of objections to this theory, among which perhaps the most important are that formic acid does not accumulate in the tissues, while, so far from succulent plants containing a high concentration of acetaldehyde, the concentration of this substance in succulents is very low (o-o1 to 0-001 %), and is, in fact, too low to have any appreciable inhibiting effect on carboxylase. From his own researches and a critical consideration of the work of others, Bennet-Clark has shown that for each molecule of sugar which disappears from succulents not more than one molecule of malic acid is formed, so that for every molecule of sugar which is lost by glycolysis at least two atoms of carbon must be involved in the formation of some other material. This is not carbon dioxide, and in fact, no carbon compound with one, two, or even three carbon atoms in the molecule accumulates in the tissues, and Bennet-Clark therefore concludes that the carbon compound formed from glycolysis along with malic acid must be built back to polysaccharide. The carbon dioxide evolved by 22 SECTIONAL ADDRESSES succulents does not come from malic acid, for the rate of carbon dioxide evolution is not proportional to the concentration of malic acid. Bennet-Clark’s view of the breakdown of sugar by succulents is thus represented by the scheme : sugar intermediate products of glycolysis —> malic acid — polysaccharide co, and the malic acid is thus an intermediate product of anabolism. Lack of time prevents a further discussion of this interesting subject of the part played by organic acids in plant metabolism: it must suffice to say that in other plants besides succulents evidence is accumulating which indicates that the part played by these acids in oxidative anabolism may be quite a general phenomenon. While then data are accumulating which indicate the linkage of anabolic processes with those of the breakdown of sugar, it is important to note that there is no evidence of the formation of products other than carbohydrates. Is it possible, however, that syntheses of more complex substances are indeed involved, and that we have here a dim glimpse of the mechanism for the production of these substances, and that along with the formation of sugar or some intermediate there may be also the formation of protein or other complex substances ; that, indeed, we have here the mechanism by which the carbohydrate is brought into a suitable form for combination with nitrogenous and other compounds ? If this is so we should expect to find the strongest evidence of oxidative anabolism in actively growing material. It is therefore disappointing that in tissues such as those of germinating seeds the indication of oxidative anabolism is often wanting. In work by Leach on the respiration of germinating seeds of different types it was found that in those seeds storing carbohydrate as their chief food reserve the ratio of anaerobic to aerobic respiration was about I : 3 or less, so that in these the experimental data suggest that the same amount of carbohydrate is broken down to carbon dioxide and water in presence of air as is broken down to carbon dioxide and alcohol in absence of oxygen. In seeds which contain a considerable amount of fat the ratio of the initial rate of anaerobic to the previous rate of aerobic respiration was found to be greater than 0-33, and in these, therefore, some oxidative anabolism might take place. On the other hand, a high rate of anaerobic respiration has been observed in other fruits besides apples, and it is curious that the indications of anabolism should appear in just those materials where it would seem to have least meaning. However, many seeds contain a considerable reserve of protein which suffers break- down, at least in part, during germination. Thus Isaac has shown that in the seeds of the same variety of sweet pea in which Leach found a ratio of anaerobic to aerobic respiration of only about 0-2, there is a continuous breakdown of reserve protein during the first ten days of germination, over a third of the protein disappearing in this period. K.—BOTANY 223 While a synthesis of what may be called protoplasmic proteins and other substances is taking place in the growth centres, this synthesis is much less than the breakdown of protein reserves, and it would therefore appear that in such material there is a source of energy available apart from that provided by the breakdown of carbohydrate. Before we can hope to present a picture of the relations between respiration and vital syntheses in germinating seeds, and perhaps in all other material as well, it seems to me that we need not only many more data regarding respira- tion rates under both aerobic and anaerobic conditions throughout the whole germination period, but also a detailed biochemical analysis of the carbohydrate and various nitrogenous materials present in the seedlings. So expressed, this may sound and look a simple enough matter, but actually, as anyone who has attempted to tackle such problems knows, it is one that abounds in difficulties. As far, then, as the mechanism by which respiration provides the energy for the formation of compounds of higher energy content is concerned, we are still very much in the dark. There is even the possi- bility that we are completely wrong in assuming a connection between aerobic and anaerobic respiration. While there is very strong evidence that anaerobic respiration in plants is often similar to fermentation, in- asmuch as the substrate and the end products are the same, there are so many exceptions, or apparent exceptions, to the production of ethyl alcohol in the correct quantity demanded by the equation for fermenta- tion, that one may well hesitate in accepting this view as of universal applicability. On the other hand, the opinion of Miiller and Lundsgaardh that anaerobic respiration is a process quite distinct from aerobic respi- ration, in which different enzymes function and in which the course of the breakdown is different from the beginning, has found little support from more recent work. The view of anaerobic respiration as the effect of deprivation of oxygen on the normal aerobic process, appears to me by far the more reasonable one. For if the two processes were completely independent we should expect anaerobic respiration to proceed at ail times, in both presence or absence of oxygen, or we should have to assume that oxygen inhibits the breakdown of carbohydrate to carbon dioxide and ethyl alcohol. Now the first hypothesis is untenable because it would mean that in air aerobic respiration took place in addition to anaerobic respiration, so that the output of carbon dioxide under such conditions should always be greater than in absence of oxygen, which is not always the case. Nor do the products of anaerobic respiration normally appear in presence of air. On the other hand, the breakdown of carbohydrate to carbon dioxide and alcohol by the enzyme complex zymase does not appear to be inhibited by oxygen. While it has generally been assumed that respiration is linked in some unknown way with the synthesis of proteins and other substances, its connection with those other processes, the absorption and excretion of materials which are characteristic of cells, has only come to be appreciated more recently. The absorption and excretion of water and dissolved substances was generally more or less tacitly assumed to be determined by the physical laws of osmosis and diffusion. Water was supposed to 224 SECTIONAL ADDRESSES diffuse into or out of the vacuole according to the difference between the osmotic pressure of the cell sap and the sum of the osmotic pressure of the external solution and the inwardly directed pressure of the stretched and elastic cell wall. Dissolved substances were supposed to enter the vacuole according to the laws of diffusion expounded by Graham and Fick more than eighty years ago. The method of measuring the rate of entry of dissolved substances by observing the rate of deplasmolysis of plasmolysed cells placed in a solution of a penetrating substance assumes that this substance diffuses unchanged through the protoplasm into the vacuole, where it still remains unchanged and so increases the osmotic pressure of the vacuole approximately in proportion to the amount of it which has entered the cell. Although Collander’s work on the absorption of a number of non- electrolytes indicates that this assumption may, in the case of such substances, be quite justified, it has been known now for thirty years that the entry of electrolytes into cells cannot be explained as the simple diffusion of a substance through a membrane (cell wall and protoplasm) from a region of higher concentration to one of lower concentration. In the first place it was shown that the two ions of a salt could be absorbed at different rates by living cells as long ago as 1909. In that year obser- vations of this kind were published by Meurer and by Ruhland on the absorption of salts by storage tissue (carrot and beetroot) and by Pantanelli, using a great variety of plant material. ‘These observations have since been extended by many others, and it has been established beyond a doubt that, at any rate under certain conditions, the two ions of a salt are absorbed by living cells at different rates. Since the total of positive and negative electrical charges must remain equal in the external solution, it follows that either some other ion must accompany the excess of the more rapidly absorbed ion into the cells, or that some ion of the same sign as the more absorbed one*must diffuse out into the external solution to balance the excess of the less absorbed ion remaining. If the former is the case and the external solution is one of a single salt, the solution must become acid or alkaline, since an excess absorption of kation would involve some absorption of the hydroxyl ions of water, leaving some of the anion balanced by hydrogen ions; similarly, if there is an excess absorption of anion the solution will become alkaline. It was suggested by Pantanelli that this might be the reason why culture solutions sometimes become acid or alkaline. My own experience has been that all plant tissues absorb hydrogen and hydroxyl ions with considerable rapidity, and that solutions containing plant tissue tend to become less, and not more, acid or alkaline. It would be unwise, however, to assume that such is the case under all conditions, and, as far as I am aware, there is no evidence regarding the range of hydrogen-ion and hydroxyl-ion concentrations over which absorption of these ions takes place. W. J. Rees and I found, however, that organic acids of the formic acid series are absorbed until the pH of the external liquid is as high as 6-55, a value little removed from that of pure water. At any rate, the few experiments I have made myself on this point indicate that the excess of sodium absorbed by carrot tissue from a K.—BOTANY 225 solution of sodium chloride is replaced by ions of calcium, potassium and magnesium which diffuse out of the tissue, Although to be regarded as only preliminary in character, they indicate that an exchange of ions between tissue and external solution can occur in connection with excess absorption of one ion of a salt. Even more strikingly at variance with the earlier view of solute absorption by plant cells is the phenomenon which is now generally described, not altogether happily, I think, as accumulation. In 1919 F. Kidd and I showed that when thin slices of storage tissues, carrot and potato, were placed in solutions of various salts in different concentrations, absorption took place towards a condition of equilibrium which is not that of equality of concentration inside and outside the cell, but which depends on the concentration of the salt. With dilute solutions the concentration attained inside the cell may be many times that of the solution outside, while in concentrated solutions the reverse is the case and the concentration of the salt inside, even after 48 hours’ immersion of the tissue in the solution, may be very much less than that outside. Thus, while more salt is actually absorbed from a stronger solution than from a weaker one, the absorption relative to the concentration is less, both as regards rate and total amount, from a stronger than from a weaker solution. These observations by Kidd and myself, though definitely establishing on broad lines the relationship between concentration of salt and absorp- tion, did not pretend to provide more than approximate quantitative data. Thus we found that the relationship between concentration of salt and absorption was much the same as it would have been if the salt were adsorbed by an adsorbent within the cell. It is easy to suggest that a first stage in the absorption of salts by plant cells is the adsorption of the ions of the salt by some constituent or constituents of the proto- plasm. While I have pointed out the similarity of the absorption of salts by plant cells with an adsorption phenomenon, I have more than once stressed the point that this similarity is in itself not sufficient to justify the advocacy of an adsorption theory of salt absorption. Yet it must be admitted that later work by more exact methods has only served to confirm the approximate similarity of the relationship between salt absorption and adsorption. Reference in this connection may be made to the work of Laine on the absorption of manganese and thallium by roots of Phaseolus multiflorus, as well as to observations of my own on the absorption of sodium chloride by carrot root. Further, if the proto- plasm contains adsorbents of the ions presented to it, then adsorption must take place if conditions demand it. Before leaving this question for the moment I would like to point out that it is obvious that if the similarity between the relationship of salt absorption to concentration and the adsorption equation is more than a coincidence, then adsorption can only be the first stage in this absorption, at any rate by actively growing tissues in which the absorbed ions must be transferred elsewhere. Again, the adsorbing material one would expect to be present in the protoplasm, whereas a number of more recent observations by various investigators indicate that there is actually an I 226 SECTIONAL ADDRESSES increase in concentration of the absorbed ion in the vacuole. The adsorption would then have to be followed by elution of the salt at the surface of the vacuole. In this connection it is interesting to note that S. C. Brooks has obtained some evidence that Valonia, immersed in sea-water containing rubidium chloride, accumulates rubidium in the protoplasm for two days, after which this kation passes from the proto- plasm to both vacuole and external solution. The same worker has also found that when cells of Nitella are placed in 0-o1M. solutions of radio- active potassium chloride there is an accumulation of potassium in the protoplasm after 6 hours before any appreciable amount of potassium appears in the vacuole. Previously M. M. Brooks had found that when Valonia is immersed in a solution of methylene blue the cell wall and protoplasm become deeply stained by the dye before any appreciable coloration of the vacuole is observable. If adsorption is indeed operative in the absorption of salts, one would expect it to be partly mechanical and partly electrical, and the unequal absorption of the two ions of a salt could be related to the electrical charges on adsorbents in the protoplasm. Further, the occurrence of electrical adsorption would render the conformity of salt absorption with the equation for mechanical adsorption only approximate. Another mechanism which has been suggested as possibly operative in the absorption of salts is one of interchange between ions within and without the cell under conditions which give rise to the ionic distribution between the cell interior and exterior characteristic of what is called Donnan equilibrium. If the solution exterior to the cell contains a salt both ions of which can penetrate the cell membranes, while the interior of the cell contains an electrolyte one ion of which can penetrate the membrane while the other is immobile, then at equilibrium there will generally be inequality of concentration of any ion on the two sides of the cell membrane. There are probably in the protoplasm protein salts which provide the necessary conditions for Donnan equilibrium. A difficulty is that in a condition of Donnan equilibrium the products of the concentration of any pair of oppositely charged ions should be the same on the two sides of a membrane, so that if one ion of a salt is absorbed to such an extent that its concentration is higher inside the cell than outside, the other ion can only be absorbed to a concentration inside the cell which is lower than its concentration outside. But actually this is not necessarily the case. Thus I showed in 1924 that storage tissue can absorb both ions of sodium chloride until the concentration of both is higher than that of the same ion outside the tissue, it being assumed that the ion remains active inside, an assumption for which there is good evidence. Briggs has shown that this ddes not present an insuperable difficulty to the view that absorption may be conditioned by Donnan equilibrium if the two ions are absorbed by different phases in the cell, and he shows that actual observations of salt absorption can be so explained if the kation is absorbed by the protoplasm and the anion by the vacuole. And in this connection it must be emphasised that just as adsorption must take place if the cell contains adsorbents of ions capable of reaching the adsorbent, so, if the cell system involves the conditions K.—BOTANY 227 giving rise to Donnan equilibrium, it is inevitable that the movement of ions demanded by these conditions must result. The possibility that respiration has a direct effect in bringing about the absorption of ions has been pointed out by several workers, notably by Briggs and S. C. Brooks. The production of carbon dioxide in the cell leads to the appearance of carbonic acid and hence of its ions hydrogen and bicarbonate, H and HCO;. The interchange of ions required by the Donnan equilibrium will lead to the diffusion out of hydrogen ions which are replaced by kations from the external medium, while the bicarbonate ions will be exchanged for anions from the external medium. As the tissue continually respires the production of hydrogen ions continues to replace those which diffuse into the external solution, and so the absorption of ions continues as part of an interchange between tissue and external medium. An interesting theory of salt absorption which hypothesises some sort of combination of the absorbed ions with constituents of the protoplasm followed by passage of the ions into the vacuole through exchange with hydrogen and bicarbonate ions, has recently been proposed by S. C. Brooks. According to this theory, the substances in the protoplasm responsible for the initial absorption are the proteins. In the protoplasm are proteins of various kinds, which are differently ionised, some with the protein group carrying a positive charge, others with the protein ion carrying a negative charge and thus constituting a proteinate ion. When a salt such as potassium chloride is absorbed the potassium ion unites with a H-proteinate and the chloride ion with a protein-OH. The potassium proteinate and protein chloride thus produced unite with the basic and acidic groups of adjacent molecules and so move through the protoplasm until they reach molecules adjacent to the vacuole. Here exchange with H and HCO, ions produced as a result of respiration is supposed to take place. Against the view of a direct effect of respiration on salt intake by ionic exchange it has been urged by Hoagland and Steward that accumulation of ions is negligible or slight when tissue is deprived of oxygen, although there may be a considerable anaerobic production of carbon dioxide. But as regards this objection it must be noted that under conditions of anaerobiosis the rate of carbon dioxide production usually falls rapidly with time, so that it is doubtful whether a considerable production of carbon dioxide anaerobically generally continues for any length of time. The question is obviously one requiring further experimental investigation. That the absorption of salts by tissues is related to a supply of oxygen, and probably in some way to respiration, there can, however, be no doubt. As long ago as 1913 Hall, Brenchley and Underwood showed that barley and other plants in aqueous culture solutions grew more rapidly in aerated solutions than in non-aerated ones, an observation which was confirmed by Jorgensen and myself in 1917 in regard to barley and balsam and by Knight in 1924 with wallflower, Chenopodium album and Elodea. The conclusion could be drawn that in these experiments the augmenta- tion of the oxygen supply to the roots brings about an increase in the rate of absorption of the nutrients necessary for metabolism and growth, 228 SECTIONAL ADDRESSES but the problem is complex, for the effect of carbon dioxide accumulation in poorly aerated solutions may bea factor, and there is a marked difference in the reaction of different species, for both Free in America and Jorgensen and myself in this country found that buckwheat cultures did not react to differences in the oxygen supply to the roots, while as regards maize, whereas Andrews and Beal found that aeration of the culture solution very greatly increased the yield, Knight found that this was the case with soil cultures, but not with water cultures. Whether this divergence in behaviour is to be related to varietal differences or to some undefined factor in the experiments is not clear. More direct evidence of the effect of oxygen on the salt relations of the cells has been obtained in work with storage tissues. In 1927, as a result of observations on the behaviour of such tissues when placed in water either kept still or agitated, I called attention to the importance of respira- tion in regard to the salt relations of the cells. I pointed out the import- ance of maintaining the supply of oxygen to such tissues for the maintenance of their vitality, and that in the absence of an adequate oxygen supply exosmosis of electrolytes took place, leading to the speedy death of the tissues, whereas with maintenance of a supply of oxygen absorption of electrolytes continued, in the case of beetroot, for example, for periods of about three weeks. Towards the end of this time a condition of equilibrium was reached or approached, in which the content of electrolytes in the external liquid was very low. During this period conditions leading to lower oxygen and higher carbon dioxide concentra- tion led to increase in the electrolyte content of the liquid, while addition of fresh oxygen led to a decrease. In similar experiments carried out by Briggs and Petrie in 1931 in which a continuous stream of air was passed through the liquid, these workers examined the course of respiration along with the changes in electrolyte content of the external solution, and established the fact that there was a general parallelism between the rate of respiration of the tissue and the electrolyte concentration of the external liquid. If the stream of air was replaced by nitrogen the respiration rate increased, and so did the concentration of electrolytes in the solution, while replacement of the nitrogen by air brought back the original dis- tribution of electrolytes between tissue and external liquid. Steward and collaborators have shown that reduction of the oxygen supply to storage tissue of potato, carrot and artichoke below a certain value limits the accumulation of both the ions of potassium bromide by the tissues, while Hoagland and Broyer have obtained a similar result with barley root systems. In attempting to explain this effect of oxygen one must bear in mind that the relationship between respiration and salt accumulation may not be a direct one. The maintenance of an adequate supply of oxygen is necessary to maintain the vitality of the tissue, possibly on account of the deleterious effects of the products of anaerobic respira- tion. Thus the fact that accumulation depends on oxygen supply may be regarded as an expression of the fact that under conditions of partial or complete anaerobiosis the functioning of all or many vital processes dependent on the protoplasm is adversely affected, and along with them that of salt accumulation. From this point of view the effect of conditions K.—BOTANY 229 leading to poor oxygen supply may be related not only to oxygen con- centration but also to accumulation of carbon dioxide and other products of anaerobic respiration. Hoagland’s observations on the absorption of potassium bromide by cells of Nitella may, perhaps, be of significance in regard to the part played by oxygen in salt absorption. He found that absorption of bromide only took place if the cells were exposed to light, or if they have been previously exposed to adequate illumination. If for some time previously they had been growing in weak light no accumulation of the salt or its ions took place. From a consideration of all the data it seems to me that the following conclusion can be drawn regarding the relationship of respiration to the absorption of salts by plant cells, namely, that accumulation of salt depends on the vitality of the cells and that the maintenance of this vitality depends, as has been long recognised, on the presence of oxygen, either because aerobic respiration or some other process requiring oxygen is essential for this maintenance of vitality, or because in the absence of oxygen the accumulation of carbon dioxide and other products of anaerobic respiration adversely affects the function- ing of the protoplasm. ‘This dependence of absorption of salts on the vitality or healthiness of the tissue was clearly shown by my experiments of 1927 and the later ones of Steward in which stress was laid on the effect of aeration of the tissues. I think Hoagland’s observations fall into line with these. Nitella kept for some time in low light is probably somewhat unhealthy, just as is tissue that is deprived of an adequate supply of oxygen. In other words, most of the work published on the relationship between respiration and salt accumulation does no more than show that this accumulation is a vital process, depending on the normal functioning of the protoplasm. Any general relationship between respiration and salt accumulation, as regards the linkage of reactions involved or the transfer of the energy required for the entry of a salt against its own diffusion gradient, may thus be very indirect. This view of the necessity of oxygen for salt accumulation does not rule out the possibilities of adsorption, chemical combination and ionic inter- change as playing a part in salt absorption, and indeed, my experiments of 1927 and those of Briggs and Petrie of 1931, to which I have earlier referred, are most readily explicable in terms of ionic interchange. Apart from the more obvious physico-chemical relationships already mentioned, what is called decline in vitality, health or activity is associated with changes in the protoplasm, which may involve changes in the state of aggregation of the protoplasmic colloids and in the distribution of their various constituents, which will profoundly alter their capacity for ad- sorption or chemical combination and the nature of ionic exchanges. I am certain that in the present state of our knowledge there is no justi- fication for putting aside any of these processes as possibly playing a part in determining the salt relations of cells. What is required for the clari- fication of the problem I have emphasised for many years, namely, the accumulation of experimental data regarding these relations, and it should help greatly if data are obtained for different kinds of cells and with different kinds of solutes. With the development of both chemical and physical methods for the measurement of small quantities, such data can 230 SECTIONAL ADDRESSES now be obtained which were impossible to acquire twenty or even ten years ago. The katharometer, spectrograph and polarograph are three physical instruments which in particular will prove of the greatest aid to such work. One significant fact does, at least, emerge from the information so far acquired, namely, the absorption of dissolved substances by plant cells is as much a vital process as the respiratory function and, like it, depends - on the presence of the living substance. On what does this dependence consist ? On the presence of a protoplasmic membrane, which is broken down when the protoplasm changes in the direction of loss of vitality ? On the state of aggregation of the particles in the colloidal complex which constitutes the system, and which certainly changes as the cell becomes moribund? On the respiratory process itself? On the presence of certain enzymes or other substances which are contained in the proto- plasm? I have indicated how certain suggestions have been made in regard to these various possibilities, but only further research will provide the answer. It is a remarkable fact that with the continued application of the prin- ciples of physical chemistry to the investigation of vital plant activities, it has gradually become more and more evident that simple explanations of these activities in terms of physical chemistry are not forthcoming. Even the usually accepted simple explanation of the water relations of the plant cell is now suspect. Ever since the classical investigations of De Vries and Pfeffer it has been supposed that these relations, at any rate for vacuolated cells, were explained with complete satisfaction on what I have called the ‘ simple osmotic view,’ the assumption being made that the protoplast, or the limiting layers of it, functioned as a semi-permeable membrane permeable to water but impermeable to many solutes. Now Bennet-Clark, Greenwood and Barker have found that this explanation is not always valid. ‘They have measured the osmotic pressure of the cell sap of a number of plant cells by the plasmolytic method, and also cryoscopically after extraction of the sap from the tissues. In some cases (petioles of Caladium and Rheum) the values obtained by the two methods are the same, and hence in these cases the simple osmotic view affords a satisfactory explanation of the observed facts, but in other cases (petioles of Begonia and roots of beet and swede) the osmotic value of the sap determined plasmolytically was found to be markedly greater than the value obtained for the expressed sap by cryoscopic determination. ‘This means that in the latter cases the pressure sending water into the vacuole is greater than can be accounted for by the actual osmotic pressure of the sap as determined physico-chemically, and hence such cells possess a power of active secretion of water analogous to the capacity for accumulat- ing salts which I have already discussed. That this is so is confirmed by the fact that cells of such tissues are not plasmolysed by their own sap, whereas in the case of those tissues which do not exhibit this phenomenon approximately half the cells of the tissue are plasmolysed by sap ex- pressed from the tissue. So here also the vital activity of the protoplasm is operative, and it may be presumed that the energy required for this active secretion of water from the external medium is ultimately provided K.—BOTANY 231 by respiration, but how the transfer of the energy is brought about is as obscure as in the case of salt accumulation. Thirty years ago, when the importance of the principles of chemical dynamics in life processes was coming to be fully realised, it looked as if the solution of many of the problems of plant physiology in terms of physical chemistry was fairly imminent. But with the application of these principles to our investigations into living processes we find that in every one of them the protoplasm introduces a factor which renders these processes not readily explicable in this way. Clearly we must seek an explanation in the apparent divergence of vital processes from physical or chemical laws in the constitution of the protoplasmic system, and hence a fuller analysis of this system now appears to be a requisite for further advance in our understanding of physiological processes in general. There is at present no reason to suppose that with further advance in knowledge of the protoplasmic system we shall not ultimately be able to explain physiological processes in physico-chemical terms, and I would re-affirm what F. F. Blackman emphasised in his Presidential Address to this Section thirty years ago, namely, ‘the inevitableness of physical- chemical principles in the cell.’ It is scarcely necessary to emphasise how the principles of general cell physiology must be of fundamental importance in plant metabolism, for inasmuch as this depends on the activity of specialised cells and tissues, these, wherever they are alive, must also exhibit the normal features characteristic of protoplasmic activity. The process of photosynthesis involves the absorption of substances by the assimilating cells, and, like those more general cell processes we have considered, depends on the protoplasm in some way not clearly understood, although there is a probability that at least an enzyme is concerned. ‘The passage of the products of photosynthesis from the assimilating cells to the phloem must take place according to the laws governing the movement of dissolved substances into and out of living cells in general. ‘The importance of general cell physiology to absorption by roots is obvious, and here it may be pointed out how the relatively rapid absorption of nutrient salts from soils in which the soil solution is known to be very dilute, is explained by the relationship between concentration and rate of absorption of solutes : the diluter the solution the more rapid the uptake of solute in relation to the concentration. Other physiological problems such as winter hardiness of plants and the effects of extreme conditions in general are also problems of general cell physiology. But in spheres of botanical science outside the range of pure physiology the general physiology of the cell is just as important. ‘This applies in particular to ecology. This study, in so far as its aim is the determination of the relationship of plants to their environ- ment, is indeed nothing else than physiology, a fact which was clearly recognised by Clements more than thirty years ago. Of the two groups of factors which determine the distribution of vegetation, the climatic and edaphic, the mode of action of the latter in particular can only be studied with any hope of success by those with an adequately deep know- ledge and appreciation of cell physiology. It does not need a knowledge of physiology, it is true, to determine plant distribution, but such 232 SECTIONAL ADDRESSES knowledge is essential for what Tansley, in a paper read to this Section in this place thirty-four years ago, called ‘the higher branch of ecology, i.e. the detailed investigation of the functional relations of plant associations to their surroundings.’ However desirable and necessary the collation of existing knowledge of plant distribution may be, I am certain that the solution of the fundamental problems of ecology will only be achieved by the use of physiological methods, and particularly by the application of our knowledge of the general physiology of the cell. For edaphic factors must act through the root and by the absorption of materials from the soil, or the exchange of material between the soil and root; in fact the processes of respiration and salt absorption would appear to be of the first importance. Certain aspects of mycology have much in common with physiology ; indeed, that part of mycology which concerns pathogenic organisms is inevitably closely linked with problems of the relation of host and parasite, problems which are, in their very essence, physiological. Years ago it was questioned whether the physiology of the plant physiologists was not half pathology. Certainly the reverse question can be answered with more assurance ; pathology is at least partly physiology, and therefore the principles of general cell physiology must here also be of immense importance, and an intimate acquaintance with these principles should be an important part of the equipment of the experimental plant pathologist. Perhaps no branch of botany has made such spectacular advances in recent years as that of cyto-genetics. At least it has produced a nomen- clature which rivals or excels the early efforts of the descriptive ecologists. And just as descriptive ecology can do little more than correlate certain types of vegetation with certain environments, so cytology can do little more than correlate visible structures in the cell with genetical behaviour. I cannot help thinking that a real insight into these problems also will only come with the interpretation of cytological observations in physiological terms, and that the greatest advance in the study of cytology will come with the linking up of the knowledge of the cell acquired by these two lines of investigation, the cytological and physiological. And it is surely a rather remarkable fact, one indicating how far away we are at present from the achievement of this end, that the physiologist tends to think of the cyto- plasm as the essential factor in determining vital activities, while the cyto- logist almost exclusively concerns himself with the nucleus. Neither the physiologist nor the cytologist appears at present to have anything but the vaguest ideas of the relationship between the two, a relationship which, however, we may feel sure is most intimate and fundamental to life. I would now like to pass on to the economic importance of cell physio- logy and say a few words about its importance in applied botany. We all know, but it cannot be too strongly emphasised, that botany is the pure science of a great part of the most important industry of the world, agri- culture, and that, like every other industry, it can only be carried on wisely if its practice is based on scientific principles. Almost all branches of botany are important for agriculture, but mycology, genetics, and physio- logy are particularly so, and certainly physiology is not the least of these. K.—BOTANY 233 Absorption of water and nutrients from the soil, assimilation of carbon, water relations of the plant, vegetative development, flowering and fruiting are all problems of agriculture which are essentially physiological, and in many of which the principles of general cell physiology are of importance. Similarly in forestry physiology must play as equally important a part. But besides these more obvious economic applications there are numerous industries in which the principles of general cell physiology are no less fundamental. There are all those industries, ever increasing in number and importance, which are based on some particular plant product, such as cotton, linen, jute, rubber, tea, sugar and tobacco, to mention only a few of the more important. Apart from the growing of the plants themselves, which like any other form of agricultural practice should be based on sound physiological principles, a knowledge of these principles may be equally important in the subsequent treatment of the plant material. In par- ticular a knowledge of cell organisation, the action of enzymes contained in the cell, its behaviour towards various reagents, all aspects of general physiology, are essential. Finally the great food storage industry depends greatly on the application of knowledge of cell physiology. As an ex- ample of this I may refer to pioneer work on the scientific principles of cold storage by Jorgensen and myself carried out some twenty years ago. From a consideration of what was then known of the constitution of the cell we concluded that the satisfactory preservation of certain tissues in the frozen condition depended on rapidly freezing the tissues, a method which was subsequently put into practice in certain branches of the food storage industry. It was indeed encouraging to read in the daily press last December of what was described as the scientific discovery of the week, which turned out to be none other than the rapid freezing method for the preservation of fruit, a method that had been examined and ad- vocated by Jorgensen and myself nearly twenty years previously. This is, of course, only one instance of the bearing of general cell physiology on the subject of food preservation. The effect of the conditions of storage on enzymes and other cell constituents, and on the vitality of different kinds of cells, tissues and organisms are among the problems which a knowledge of the facts and methods of general cell physiology will help to solve. With the ever-increasing mass of knowledge in the various branches of botany, an increase which is especially noticeable to-day in those aspects of our subject which are undergoing rapid development, physiology, mycology and genetics with cytology, it is impossible for anyone to be an active worker in more than a relatively very small field of botanical endeavour. We sometimes meet with reference to a mysterious gentleman called the ‘ general botanist ’ who is expert in general botany, as someone distinct from the morphologist, physiologist, mycologist or other worker in a defined field. But in these days, when to make any contribution to knowledge necessitates specialisation, there can indeed be no such person as the expert in ‘ general botany,’ for there is, indeed, no such subject. But in whatever part of our subject our own special interests may lie, we can still appreciate the efforts and aims of workers in other fields, and realise the bearing of work in these fields on our own Iz 234 SECTIONAL ADDRESSES problems, and in this sense we are all general botanists; that is, just botanists. For if ‘general botany’ as something distinct from ‘botany’ is a myth, there is no doubt that the various branches of our subject are related in the whole. In this address I have tried to indicate not only the scope and present position of our knowledge of the general physiology of the cell, but where this particular part of the science of plants comes into contact with other branches of botany, and how the application of a know- ledge of the facts, principles and methods of cell physiology may be expected to lead to an increase in knowledge, not only of the physiology of the plant, but of other aspects of botanical science and of its industrial applications. SECTION L.—EDUCATIONAL SCIENCE. THE FUNCTION OF ADMINISTRATION IN PUBLIG EDUCATION ADDRESS BY J. SARGENT, PRESIDENT OF THE SECTION. Tue British Association in general, and this Section of it in particular, have long been accustomed to Presidential Addresses which, with less than the usual compromise between truth and politeness, have generally been described as brilliant and provocative. Certainly there would be no exaggeration in applying these epithets to those addresses to which I myself have had the privilege of listening. This year I can at any rate promise the Section a change, but it will not be a change for the better. Even if, in my undergraduate days, I occasionally staggered College societies with visions of things to come, I can only say that, after twenty-five years in the service of local government, the instinct of self-preservation if nothing else has taught me to confine myself to things as they are. At the same time I am proud to be old enough, or young enough, to have been at school and college at a period when young men looked for a new book by my immediate predecessor with something of the same spirit of hope and excitement as the Christians of Macedonia may have awaited a communication from St. Paul. There was a memorable evening in our Senior Common Room when I laboured, not with entire success, to persuade our venerable Dean that, in spite of a certain similarity in title, Kipps, the book I was commending to his notice, was not identical with another modern work called Kim, which had earned his disappro- bation and was in fact by quite a different author. I will not at any rate blame my subject, even if at first sight it may appear a dull one, for the shortcomings of this address. ‘The reasons I chose it are twofold ; in the first place it is the only serious topic I know enough about to justify my discussing it in the presence of an audience of such various distinction, and in the second I am rapidly approaching a state of suspended animation so far as my association with local govern- ment is concerned, so that without aspiring to brilliance or even provoca- tion I can air my views with greater freedom and possibly less offence than any of my colleagues who are still bound to the wheel of official discretion. 236 SECTIONAL ADDRESSES At the same time I am not unmindful that this address is being delivered to the Educational Science section of the British Association, and that to some the connection between educational science and practical problems which to a large extent are common to local government as a whole rather than peculiar to educational administration may well appear remote. I am not quite sure what educational science connotes but I imagine it may comprehend not only the philosophical principles upon which educational practice is or ought to be based but also experiment and research into method. The administrative machine, particularly in the public education service, is an instrument which, if improperly employed, may well distort the first and hamper the second. For that reason alone it deserves an occasional inspection by the educational scientist whatever his particular interest may be. Moreover, in recent years the British Association has attached special importance to the impact of science on society. For the great majority of teachers, pupils and parents in this country the medium through which this impact is felt so far as education is concerned is the Local Education Authority, Furthermore this question of local administration, uninspiring as it may appear, may not be without its significance in relation to current issues of world-wide importance. Only the other day I heard a prominent member of a local education authority quoting, or as I believe misquoting, a still more eminent personage to the effect that ‘ local government is the last bulwark of democracy.’ Exactly what he meant by the word ‘ last’ is obscure, and as nautical metaphors are notoriously tricky things there is a possibility that he may have meant bulkhead rather than bulwark. I take it, however, that his meaning was that, if democracy is going to founder, the immediate cause will probably be found not so much in the legislative eccentricities of Parliament as in the inefficiency of local administration. It is when men begin to feel miserable that the value of political liberty begins to slump, and it is when intelligent men feel the pinch worst that revolutions begin to happen. It may be a hasty and in- adequate generalisation, but there seems to me to be much in the view that the totalitarian state has arisen from the economic and spiritual destitution of the professional classes. I must, however, resist the temptation to platitudinise on this popular problem and try to confine myself to certain tendencies in the administration of local government, and of education in particular, which can have at most only an indirect bearing on the much wider question of the relation of the State to the individual. Political thinkers throughout the ages have frequently defined or described the function of administration. Of all their attempts the one which appeals most to an harassed official is the late Lord Fisher’s cynical aphorism that it consists in the intelligent anticipation of agitation. From a somewhat less negative point of view it may be regarded as com- pounded of deliberation and execution, of which the latter should but does not always follow the former. In very simple terms, administration is neither more nor less than a method of transacting business, and particularly public business, as cheaply and as quickly as is compatible with doing it reasonably well. Even this lacks precision and is by no means free from ambiguity. Where for instance is the standard to be L.—EDUCATIONAL SCIENCE 237 found by which from time to time ‘ reasonably well ’ shall be measured ? It may be argued that the practical administrator will in fact know at any given time the standard he has to aim at in order to satisfy public opinion, just as the craftsman may point to contemporary taste as the criterion of production. Whether it is possible or not to find an acceptable definition of adminis- tration, it will probably be agreed that it expresses itself through two functions, the legislative and the executive. Most of the administrative problems which come within the purview of local government fall in the latter category. By a process which is at once historical and natural, the legislative side of administrative activity has remained largely in the hands of the central Government, though it would be to fall into an error which professed experts have not always avoided if the fact were overlooked that in many instances experiments legitimately conducted by local authorities within the powers conferred upon them by Acts of Parliament have often led to new ideas and consequent legislation. Side by side with this distribution of legislative and executive activities, and to a large extent determining it, there has proceeded a fundamental change in the conception of the function of the State in relation to the individual citizen which has marked the last century and, with increasing emphasis, the last quarter of it. The change to which I refer is one from a negative to a positive con- ception of legislative objectives and has profoundly modified the scope and character of local administration. Until a hundred years ago the main interest of government was to restrain men from living evil lives ;_ since then the intention, however mysterious in operation, has been to help them to live good ones. This change has coincided and is’no doubt connected with another conception widely developed if not created during the same period, viz. the idea of human progress or the infinite perfectibility of man. A social order designed by those who believe that every day and in every way men are getting better and better may be expected to exhibit fundamental differences from one the main object of which is to postpone as long as possible the coming of inevitable decay. The obvious result of this evolution from a negative to a positive view of the function of government has been a vastly increased interference by the State in the goings and comings of the ordinary citizen; and the problems which form the subject of this paper arise from the steps which have been and are being taken to make this interference effective. The growth in this business of government, as in other businesses, has forced home the need for administrative devolution, with the consequent rise of local government as the machinery through which much of the will of Parliament must be implemented. It is no part of this paper to try to trace the process of this devolution, but it is relevant to point out that there have been occasions when the need for defining satisfactorily the respective spheres of the central and the local government has presented itself as an extremely urgent problem, at any rate to the minds of many local administrators. ‘There is little, however, for me to say on this point because the rules according to which 238 SECTIONAL ADDRESSES the game is to be played are now generally accepted, and the players, in my experience, are observing them in an increasingly friendly and harmonious spirit. We all think and may even speak unkindly about Whitehall from time to time, but on calm reflection cannot but admit that we are treated on the whole with delicacy and consideration. There is one aspect of this relationship, however, which is important, and that is the financial one. I shall have something to say a little later on the question of the adequacy or otherwise of exchequer grants so far as Local Education Authorities are concerned. On the wider issue we may rest content with the fact that, whatever arguments may be adduced or principles invoked, so long as there are local administrators they will continue to pursue the laudable object of getting as much money and as little interference from the central authority as they possibly can. But if devolution is to remain a necessity, and granted the continuance both of a democratic system and of the parental interest of the State, there seems no alternative. The really disconcerting problems for the future seem to me to arise from the present nature of the local government bodies themselves. The first difficulty would appear to lie in the unit, i.e. in the size and geographical distribution of local government areas. Recognised authorities, who are mostly foreigners and seem to regard our political institutions with greater enthusiasm than we do ourselves, tend to congratulate us on our ingenuity in adjusting them to meet new social and economic needs as they arise. It would be difficult to detect this evolutionary process at work so far as local government boundaries are concerned. It is true that towns have grown and encroached on county areas and that there has been a distinction in the degree of autonomy conferred on authorities of different sizes by successive Acts of Parliament, but substantially it remains true that our local government boundaries derive mainly from Saxon times when the problems of modern administra- tion can hardly have been foreseen. When the present Local Education Authorities were established by the Act of 1902, there was an opportunity to devise areas with regard to administra- tive convenience rather than historical association, but it is significant that there does not appear to have been any serious suggestion to do other than to allocate the new powers and duties among the existing local units. Consequently we find the control of public education, under the benevolent supervision of the Board of Education, distributed among 318 different bodies varying from London with 4,396,821 inhabitants down to Tiverton (Devonshire) with 9,610. These Local Education Authorities inherited the property of the School Boards and Technical Instruction Committees, including a number of buildings in various states of repair, and of officials in much the same condition, together with some strange and embarrassing residuary legacies, like the Cockerton Judgment and Dual Control. It is very much to their credit that within three and a half decades, with a great war intervening, they have not only introduced some kind of order into this confusion but have also built up a great system of secondary education, put the salaries of teachers on a more satisfactory basis, and undertaken the task of reorganising the whole system of so-called L.—EDUCATIONAL SCIENCE 239 elementary education, the full effect of which it is too early to appreciate. It is significant of the success they have achieved that those pioneers in public education, the Scots, should recently have reconstructed their administrative machine on the English model and so driven another nail in the coffin of the ad hoc education authority. And yet we must confess that we are still very far from that adjustment of opportunity to ability which is, I suppose, the fundamental aim of any democratic system of public education. If I appear to be devoting most of my time to pointing out the defects in our local education system, I should like to make it clear that my object is to contribute my mite towards smoothing out the long road which has yet to be travelled and in no way to belittle the efforts of a by no means ignoble army of public servants. Apart from questions of size and population, Local Education Authorities also vary greatly in their financial resources as regards both their own rateable value and the contributions which they receive from the Exchequer towards their net expenditure. Neither the money they raise themselves nor the grants they receive from Government are in any arithmetical proportion to their respective areas or populations, and, although the formula by which the grant is calculated was no doubt intended to take account of local circumstances affecting expenditure, the conditions which it was designed to meet in many cases no longer obtain. The resultant anomalies are a fruitful cause of dissatisfaction in many areas and of acute embarrassment in some; in fact the whole question of the financial relationship between the central government and the local authority is one which calls for an immediate and comprehensive review. Then again Authorities vary very much in character, some being purely rural, many purely urban, while others contain a mixture of the two, or are in process of transition from the former to the latter. A further and ever-present difficulty so far as many of them are concerned is the fact that while some of them are empowered to deal with all forms of education in their area (Counties and County Boroughs, technically known as Part II Authorities), others are only empowered to deal with elementary education (Part III Authorities). Part III Authorities, and particularly the smaller ones, are naturally jealous of their prerogatives and one cannot but admire the courage with which many of them are facing the strain on their resources, financial and otherwise, which the provision of ele- mentary education on reorganised lines must entail. At the same time, when it is realised that ‘ higher ’ education usually starts at the age of 11 or even earlier, while ‘ elementary’ education will shortly extend to 15 or even 16, and that most of the larger Part III Authorities have exercised the right of establishing selective central schools, which in many cases approxi- mate in standard and aim to the other forms of selective post-primary institution provided by the Part II Authority in the same area, the possi- bilities of confusion, overlapping and friction will need no emphasis. It is true that many of these difficulties can be and are in fact being overcome by co-operation between the Authorities concerned, but it should be pointed out that, while co-operation ranks high among the 240 SECTIONAL ADDRESSES blessed words in the educational vocabulary, it usually involves a com- promise and is never the ideal method of administrative procedure. No departmental chief, I imagine, would set two typists to type the same letter or two office boys to lick the same stamp simply in order that they might have the advantage of co-operating. The next problem is concerned with the personnel of the Local Educa- tion Authorities. The personnel is divided into the amateur and the professional elements, or the unpaid and the underpaid as I have heard it expressed. The amateur element is again divided between persons co-opted for their knowledge of and interest in education, and others elected by the people not solely, experience suggests, because they are known to possess either or both of these qualifications. The co-opted members for obvious reasons are generally among the most valuable members of an Education Authority, but the fact that they are not members of the County or Borough Council, and so have no direct re- sponsibility to the electorate, is usually regarded as disqualifying them for occupying really responsible positions, e.g. chairmanships of committees. The most serious aspect of the problem to my mind is the steady and even accelerating deterioration in the amateur personnel which has taken place since the War. ‘This is particularly marked in the case of the elected representatives of the people. The reasons are as plain as the fact. The most obvious of course is the gap caused by the War itself in the ranks of those who, if they had survived, would probably have been the first to offer themselves for public service. But this is by no means the whole or even the main explanation. ‘The vast increase in the responsibilities laid upon local authorities by legislation since the same period makes it necessary that any member who is to become really au fait with the business of education should be able to devote a considerable amount of his weekly time to it, whereas before the War it was possible for a person of average intelligence to grasp not only the general lines of policy but also day-to-day happenings by occasional attendance at committee meetings. Outside tendencies have also been at work during the same period to make such extra attention increasingly onerous and difficult; the business of making a living has also become more strenuous, and people, who might have been able to devote before the War the amount of time which was necessary to grasp the business of administration, now find themselves, so far from being able to give the additional time which the increasing duties demand, in a position to give much less time than before. Consequently local administration is being progressively denuded of persons actively engaged and occupying positions of responsibility in industry and commerce. There seems no sign whatever that either of these tendencies is likely to lose its effect. Everything in fact points in the other direction, and the result is already apparent in the increasing tendency of Education Authorities to consist of people who have retired from work, or have never had work, or who are in fact professionals rather than amateurs because, as Officials of political or other associations, it is expedient for them to become members of Local Education Authorities from the point of view of promoting the objects which their associations have at heart. It is no L.—EDUCATIONAL SCIENCE 241 reflection on the personal integrity of these last to express the opinion that they constitute a serious danger to the system on the ground that if there is a bureaucratic habit of mind, and if as some people believe it is inimical to good government, these people possess it and bring it to bear on their consideration of educational problems without the saving grace of the professional educationist’s training in and knowledge of the particular branch of administration with which he is dealing. There remain, of course, many splendid people who give their services to educational administration, and I must safeguard myself against appearing to suggest by the use of the word deterioration that graft or other forms of dishonesty are on the increase. ‘That, I am glad to say, has not been my experience. There is the risk, however, which is more than theoretical, of intellectual dishonesty creeping into the discussion of educational affairs when the Authority contains any substantial number of members who are pledged to a set of opinions which may have a cross- bearing on purely educational considerations. As I have pointed out the difficulties—I will not say the defects—in our local government system at considerable length, I suppose I am under some obligation to attempt to indicate possible remedies. So far as the numbers, sizes and financial arrangements are concerned, it is not difficult either to indicate the general lines which reform in theory should follow or to envisage the practical difficulties which will confront the reformer when he sets out to tamper with the traditional boundaries of English local government. It would be a bold man who would under- rate the strength of that local feeling which in its nobler aspects is not unworthy of being termed local patriotism, but at other times merely vocalises the parish pump. It is, however, possible for prac- tical experience and even a priori reasoning to suggest certain of the attributes which the ideal local government unit should possess. It should be large enough to be able to provide the variety of services which a modern community requires, but not so large that the day-to-day discharge of routine administration necessitates a rigid or bureaucratic attitude towards the problems presented for solution. In education in particular it is important that the area should contain sufficient children or students to justify the provision of the various types of educational institution which modern needs demand. It is difficult, for instance, for a small area to face the cost of modern schools, particularly of the most expensive form of them, the technical college, and although a solution may be found in co-operation between neigh- bouring Authorities, it does not always follow that Authorities who are contiguous geographically have similar needs, and there is also the risk that the standard of co-operative effort may come to approximate to the lowest common multiple among the Authorities concerned. Another important consideration from the economic point of view is that the Authority should be sufficiently large to be able to obtain good contracts for the supply of the various materials which it requires. Modern methods of mechanisation and rationalisation have been slowly but surely invading the province of local government, but their advocates have not always been ready to recognise the fact that, while centralisation 242 SECTIONAL ADDRESSES under the control of one committee or one officer makes for efficiency and economy up to a point, the stage can easily be reached when the activities and responsibilities both of the committee and the officer become so large that neither they nor he are able to keep the threads comfortably within their grasp. When this stage is reached the question of devolution becomes just as important as that of centralisation at the earlier stage. I have come to the conclusion that for Education Authorities, and I believe for other Authorities also, the minimum size of any local govern- ment unit should be an area with a population of 250,000 ; the ideal size would be between 500,000 and 750,000, and the maximum size 1,000,000. The establishment of areas of this size would, of course, pre-suppose the total abolition of Part III Authorities, by conferring complete autonomy on the largest, or on the amalgamation of others where they are geographically contiguous, and by abolishing the rest. There is one other matter in this connection which is worth some consideration, and that is the question of so redistributing areas that none of them may in future be exclusively rural or exclusively urban. This is a proposition which has commended itself widely to many social reformers who have advocated a regional organisation for local government. I am not sure that it is quite as important as some of its advocates have supposed, partly because with the development of modern transport and of town and country planning the difference in outlook and needs between the town and country dweller is tending to disappear. I would, however, admit that in such matters as technical education a purely rural area tends to be penalised, at any rate where agriculturists have still to realise that their industry is just as much in need of technical instruction as any other. To some extent the establishment of geographical units of a more uniform and rational size would contribute towards the solution of the major difficulty of personnel because, while it is true that some small Authorities enjoy admirable committees and officials whereas some of the larger ones are notoriously below standard in these respects, it will remain true on the basis of probability that within reason the larger the area the wider the choice it will have among people for its members of committees, and the larger salary it will be able to afford and consequently the wider field it will be able to draw upon for its administrative appointments. Larger areas and higher salaries will not, however, by themselves over- come the personnel difficulties which have bulked so largely in this paper. Unless people who are competent to govern can be made to realise that the preservation of liberty must depend on the capacity of those who voluntarily serve the community, that is, unless people are moved in greater numbers to offer themselves for public service by the Socratic urge, namely, fear of being governed by worse people than them- selves, the prospect of arresting the deterioration in the amateur personnel of local authorities is small. Something of course may be done by so easing the burden falling upon committees that members may be freed from the tedium of what are at . present known as ‘ dustbin’ debates and enabled to devote themselves to the wider issues of policy and the supervision of their officials. The L.—EDUCATIONAL SCIENCE 243 trouble is that the present type of member often prefers the ‘ dustbin ’ debate to any other kind because its subject is a matter with which he is familiar ; it is common experience that memoranda embodying recom- mendations of high policy are much easier to get through committees than those which deal with comparatively trivial issues. It may be a pessimistic opinion, but my own view is that local govern- ment will have in future to counteract the deterioration in its amateur element by a corresponding improvement in the professional element ; that is, it will have to look to recruiting better officials in the future than it has recruited in the past. This is not simply a matter of higher salaries, it is more a question of placing the training and status of the local govern- ment officer on a basis at least equal to that of the central civil servant. I am not shutting my eyes to the fact that there has been a steady improve- ment in the conditions of service for local government officers during the last twenty-five years and, as a natural consequence, in the type of officer who is now coming forward. In the education service, for instance, the Associations of Local Authorities have recently approved proposals affecting the status, emoluments and recruitment of entrants to the higher ranks of the service. Other people thinking along other lines have played with the idea of the City or County Manager. There may be possibilities in this idea provided that areas do not exceed the limits to which I have already referred, and provided that the traditional idea that the chief officer of an Authority should be a lawyer can be finally laid to rest. The legal mind has many virtues and administration would become chaotic without its restraining influence, but it is by temperament and training a restraining influence and is consequently unfitted to take quick decisions or give prompt effect to them when taken. But if there is any validity in my contention that the salvation of democracy as exemplified in our local government is to be sought in an improved type of official, I must in conclusion try to give some answer to the question, ‘ Who is the happy warrior?’ The Association of Directors and Secretaries for Education, of which body I am proud to be a member, answered this question more adequately than I can hope to do so a few years ago when they gave evidence to a Royal Commission on Local Government, and I can only refer those interested to a document which is almost lyrical in its fervour. Speaking in more mundane terms, I would say that the educational administrator should have had a university training and some experience as a teacher in one branch or other of the education service. It is essential that he should possess the qualities of a sound administrator, that he should know how to initiate, when to delegate, when and where to advance, how to endure setbacks—above all, how to handle men. If he can retain a genuine enthusiasm for the science of education, it will not be so necessary for him to have a profound knowledge of educational theory. Finally, he must beware of the hardening effects of custom and precedent. The needs of society are changing rapidly and it is the func- tion of all educators to study these needs and to consider how best they can be met. At its highest this demands from him a philosophy of life in which he is compelled to study continually the philosophical basis of 244 SECTIONAL ADDRESSES education and the principles on which this great human science has developed ; at the worst he can fall back on Pope for comfort and inspiration : ‘ Whate’er is best administered is best.’ There is a story that there was once a subaltern in a famous cavalry regiment who was so stupid that his brother officers noticed it. There is an equally apocryphal incident of an educationist who was so platitudinous that an educational conference noticed it. I wonder whether I have emulated him. SECTION M.—AGRICULTURE. LEY-FARMING AND A LONG-TERM AGRICULTURAL POLICY ADDRESS BY PROF. R. G. STAPLEDON, C.B.E., M.A., PRESIDENT OF THE SECTION. My own leaning is towards the word ‘ley,’ although according to the Oxford Dictionary this word is obsolete, but in adopting ley I follow the best agricultural precedent. It is not my intention to talk about farming for laymen, for in my opinion ley-farming properly understood is the most highly scientific farming that it is possible to practise. The ley farmer must be a proficient stock-master and a proficient cultivator, versed alike in the arts of animal and crop husbandry. ‘To be a farmer’ is ‘to till the soil,’ and in ‘till’ is implied the bringing of the soil into a fit condition for the production of crops—the care of the soil. A farmer in the true and proper meaning of the word is a man who has ever before him two pur- poses: the one to put all his fields to optimum use in respect of com- modity production, and the other, and of even greater ultimate importance, to attend to the maximum need of all his fields in respect of soil fertility. Thus judged, my thesis is that the ley farmer is a farmer in excelsis. My address has to do with the most honourable, and what should be the most venerated, aspect of the whole of agriculture—the rotation, for upon the rotation I claim everything depends. So I at least respond to the honour that has been done me in placing me in the position in which I find myself to-day in the selection of my subject. It is a neglected subject. I am the first President of Section M to do homage to the rotation. I have researched amongst the utterances of my distinguished predecessors ; incidentally, although only of interest to myself, I find that the first Presidential Address to Section M was given by Sir Thomas Middleton in the year that I came into Wales and began my researches on grassland—that was in 1912. The only mention of the rotation in the total of twenty-four addresses that have been given was by Sir John Russell, who in 1916 started off promisingly with winter corn: spring corn: fallow, but to my intense disappointment followed the rotation no further. In view of the immense amount that has been published during the present century it is not without significance that the leading agricultural journals contain but few articles dealing primarily, or even remotely, 246 SECTIONAL ADDRESSES with the rotation, and next to nothing relative to the basal philosophy of the rotation. The truth is that agricultural thought in recent decades has turned ever more exclusively towards the narrow, too narrow as I think, path of commodities, each considered as such. Excessive con- centration on commodities leads inevitably towards monoculture, and to what we too lightly please to call specialisation, and leads away from the rotation and ultimately to disaster. Greatly daring, then, I have set myself to combat this modern fetish of over-concentration on commodities, a fetish that has revealed itself not only in the trends of agricultural science, but in a very great deal of what the State has endeavoured to achieve for agriculture and which daily reveals itself in the actions and utterances of the leaders of the agricultural industry. I think that everybody will be agreed that such is the precarious state of the world to-day, and of this country in particular, that there can be only one approach to the problems of agriculture, and that is the national approach. We must not so much consider what is good for the farmer as what is good for the State: then what is good for the State must be made good for the farmer. That is the only possible approach towards a stable and long-term agricultural policy. A long-term agricultural policy, if it is to be enduring and adequate, must envisage both present and future needs of the State. ‘The success of the policy must be judged in the main by one overriding consideration, namely, the sureness and rapidity with which the farmers of the country (all the farmers of the country) in order to meet any emergency prove themselves able either to pass from the production of one series of commodities to the pro- duction of another, or, radically to alter the proportions of the several commodities produced. It so happens, at least it appears to me, that the present needs of the State, and also the more menacing of the foreseeable contingencies, unite to demand one and the same essential contribution from our agriculture. It is not for me to attempt to decide whether war danger, or the danger of our about-rapidly-to-dwindle population is the greater peril; little less disconcerting are the effects of soil erosion and soil depletion in those countries from which we are wont to obtain abundant and cheap supplies of food. I am concerned with a long-term agricultural policy, the kind of policy that would take at least ten years to put into full operation, and consequently we have to consider not so much immediate war danger as war danger as such, a danger that owing to our island position would seem to be something from which it is now hard to see how we shall ever escape. I believe the extent of the influences of soil erosion and depletion are not even yet fully realised. All methods of countering this must in the last resort react against the British housewife, and must tend to in- crease the cost of overseas production, while taking soil erosion, soil depletion and land deterioration together a vaster area of the globe is undoubtedly affected than is generally supposed. Our own rough and hill grazings have manifestly deteriorated : witness the spread of bracken, to quote only the most obvious but by no means’ the most serious example. They have become increasingly depleted of lime and phosphates in recent decades, and the same thing must be happening to a greater or lesser extent—and sometimes accompanied by actual erosion—in all the great ranching areas of the world. In framing M.—AGRICULTURE 247 our own long-term agricultural policy heed must be taken of every shred of evidence on land deterioration that is available all the world over, for it is patent that when the sum is totted up the total will far exceed what is already only glaringly manifest. The immediate, and on all hands generally admitted, need of our peoples is an abundance of fresh food. An abundance of fresh food is not compatible with a superabundance of permanent grass. Since permanent grass flows like the sea right up to the very doors of some of our largest centres of population, such centres of population are auto- matically denied an abundance of really fresh vegetables. I make no apology for this somewhat long, and in a sense non-agri- cultural and at all events non-technical introduction, for it seems to me imperative to stress our national needs, for it is these needs which should govern our whole agricultural outlook and, therefore, should determine all our systems of farming. To sum up so far, and on the strength of the various considerations I have brought forward, I would say this. What is demanded of our agriculture is, firstly, to maintain as large a rural population as possible, for probably on a large and contented rural population depends to a marked degree the increase of our population as awhole. Secondly, to maintain as large an acreage as possible in a highly fertile and always ploughable condition, and thirdly, so to conduct our farming as to allow at all times, and in all places, for the absolute maximum of flexibility in commodity-production. Before further developing my argument I must endeavour to put ley- farming in its proper perspective in relation to other systems of farming. I must therefore, and as a further preliminary, attempt to define the systems of farming as conducted in this country. My concern is to define the systems not in terms of commodity pro- duction, but in terms (a) of their flexibility, (b) of their indebtedness to imported feeding stuffs, (c) of their relation to the maximum needs of the soil in the matter of maintenance and enhancement of soil fertility, and (d) as to the amount of labour demanded. For if my major premises are anything approaching to correct, these are the matters of supreme national importance. My classification is, of course, amenable alike to amplification and simplification, and I put it forward to-day quite tenta- tively, and primarily to illustrate the principles which I consider absolutely basic to any rational consideration of a long-term agricultural policy for this country. Here is my classification. Arable Farming—A small acreage of permanent grass—a few odd corners, a couple of fields—may be conceded to even the arable farmer. For the rest he must be presumed to take the plough around his whole farm, and (a) work on a rotation of crops without any resort to the ley,” or 1] first put forward this classification in an article, ‘Agricultural Policy,’ appearing in The Fortnightly for March 1938. 2 A ley is a field sown down to grass and/or clovers, and is such that it is designed to take a definite place in the rotation of crops. Leys are of two main types: the one-year, or ‘ arable’ ley, and the ley of two or more years’ duration. Implicit in the idea of the ley is, however, the conception of ‘ due date’: after an appropriate, and within fairly narrow limitations, pre-defined, period it becomes due to be ploughed up. 248 SECTIONAL ADDRESSES (6) adopt a rotation which involves the use of the one-year ley only. The arable farmer as thus defined is never a grazier. When the one- year ley is employed this is for the primary purpose of producing hay for horses or stall-fed animals, and contributing to the muck heap, while the clover sod as such contributes to the fertility of the farm. The major function of the ley is here the maintenance of soil fertility. The chief concern of the arable farmer is the production of cash crops. His system is capable of extreme flexibility within the sphere of crop husbandry, it is capable of employing much labour—market gardening, and relatively little labour—mechanised wheat growing. It is a system: which from the point of view of soil fertility is easily abused, and which in some of its forms, e.g. market gardening, makes excessive claims on farm and stable manure (when obtainable) from sources outside the boundaries of the farm. The robbing of ‘ Peter’ (‘ Peter’ in this case being the hay and straw producing fields of other, and often remote, farms) to pay ‘ Paul’ (the truck crop fields) is an aspect of large-scale market gardening which has from the national point of view, I think, never been fully appreciated.® It is likely that the market gardener in his own interest will be driven increasingly to adopt a system of alternate husbandry as presently to be defined—town stable manure being a rapidly waning commodity. Alternate Husbandry, or, as I prefer to call this system, Ley-Farming.— A couple or so fields of permanent grass can be conceded to the ley as to the arable farmer, but for the rest the ley-farmer takes the plough in ordered sequence around the whole farm. Ley-farming is of two main types, but always the majority of the leys employed will be of two or more years’ duration, and always in any particular year the area of the farm in leys (and therefore in grass) will be not less than one-third of the plough- able acreage ; will frequently be over three-quarters of that acreage, and in extreme cases, and at unusual periods, the whole of the farm may be in leys. The main points to be emphasised are these. ‘The ley-farmer is of necessity, and essentially, a grazier and a crop husbandryman; he may also be a feeder. He must, therefore, be equipped for crop and animal husbandry, and, as I have already said, to be successful he must be proficient in both arts of farming. His system, his mental stock-in- trade, and his equipment on the farm all bear the same hall-mark, and the hall-mark above all others of value to the nation, to wit, FLEXIBILITY. The ley to the ley-farmer has two equally important functions to perform: the sward, or animal ration function, and the sod, or soil fertility function; of this duality, which to my mind is at the root of successful farming in all the moderate to high rainfall areas of the temperate regions of the world, I shall in a moment have much more to say. The two main types of ley-farming I will define as follows : The Arable-Grass Rotation.—In the arable-grass rotation most usually the leys are of two or three years’ duration. The area in grass at any time will not exceed 50 per cent. of the farm, and may be somewhat less: 3 A good many acres near London once devoted almost entirely to the produc- tion of hay for the City horse, and therefore also of manure for the market gardener, still show the mal-influence of that type of monoculture. M.—AGRICULTURE 249 Good examples of this system are the arable dairy farming of Denmark, and the rotations practised in Aberdeenshire in connection with beef production. In both cases animal products are the chief concern of the farmers, and the holdings produce at least a good proportion of the winter rations. The mechanised cereal grower may also adopt the arable- grass rotation, primarily with a view to maintaining soil fertility and to making it easier to get on his land during periods of sketchy weather. A typical rotation would be wheat : grass : grass : wheat. Grass-Arable Rotation.—In these rotations the majority of the leys are left down for long periods, from four to as many as twelve, or in some cases even more, years. Most usually as much as three-quarters, or even more, of the farm will be in leys at any one time. Ordinary animal products are the major concern of those following the grass-arable rotation, and it is on these farms that dairy bailing, poultry and pig folding are often such important and telling features of the system. Grass-arable farms at a moment’s notice can be turned over to cereal production on a grand scale and hence, if for no other reason, the enormous importance of the system and of farms conducted on this system to our national welfare. What is achieved by this system properly conducted is to farm without wasting a gallon of urine or a blade of grass; it marries the animal to the soil as can no other system, and ensures that the sod performs its maximum function in respect of soil fertility and crop production, and the sward its maximum function in respect of animal production. The nation is under an incalculable debt to Mr. Hosier and his followers, and this will eventually be realised, for it is not so much what the Hosierites do on their own acres as the principles which underlie their activities. To the credit of ley-farming as a whole is to be placed the fact that it makes heavy, or at least reasonable, demands upon labour; it is less dependent upon imported feeding stuffs than most other systems, and it maintains its acres and its practitioners in a condition of maximum flexibility and ready for anything. Nondescript.—In so far as acres are concerned the nondescript system is the one I should imagine most generally practised in England and Wales. I mean when a man practises ley-farming or arable-farming on one corner of his farm, and maintains the rest in permanent grass. Such a system is not incompatible with reasonably high production, but it is under this system that we see some of the worst examples of slovenly, negligent and deplorable husbandry. Our nondescript farms stand as a token of the fact that a system of farming by which under present condi- tions a farmer may contrive just to keep body and soul together is likely to be a system completely out of harmony with the needs of the nation. Many nondescript farms are family farms, and the amount of tillage is a function of the size of the family, or of the number of sons willing to stay at home—both dwindling in number. Permanent Grass——The permanent grass farms are those upon which there is no cultivation of any kind: on some it is still possible to find a plough, but only as a museum specimen. The number of permanent grass farms has demonstrably increased ; such farms are apt to be run together, when generally fences will be more than ever neglected and the whole (and too large) unit operated as a ranch. In the national interest, 250 SECTIONAL ADDRESSES as I have defined and envisaged that interest, this system suffers from every conceivable defect. In the first place, speaking quite generally, the permanent grass farms contribute nothing more valuable than inferior hay to the winter ration; they afford the minimum of flexibility, and maintain the minimum of acreage in a ploughable condition. Permanent grass farms serve as an excuse for an immense amount of national and private laxity, because’in brief, however bad they are they generally have some slight earning capacity, and that with the minimum of trouble to anybody—landlord, agent or farmer. Thus these farms frequently stand on land in urgent need of drainage and of lime, and so in the main they continue to stand.* It is perhaps the greatest tragedy of British agriculture that even the poorest of poor grass has some earning capacity. Milk production on permanent grass farms, and especially on those deficient in lime and phosphates—and they are many—and particularly where the stationary night paddock figures prominently in the manage- ment, stand as the best example I know of ultra-dependence on imported feeding stuffs and exaggerated waste of the manurial residues from such feeding stuffs: waste as such down the drain, and waste because of extraordinarily inept grassland management (on this latter point I will enlarge in a moment); waste also of the potential fertility tied up in the sods of the night and other more heavily dunged and urinated paddocks. At this point I would urge that unless we know the number of farms and the gross acreage of such farms operating on each of the four systems I have enumerated we know next to nothing as to how this country stands relative to potential food production. Furthermore, schemes for helping the farmer via commodity subsidisation and by planned marketing cannot be assessed in their influence on the maintenance and enhance- ment of soil fertility—and that is what matters above all things—unless we know the systems of farming under which the assisted commodities are being predominantly produced. How much quota wheat, for example, is being produced respectively on arable farms, nondescript farms, or on ley farms? Where is most of the milk being produced—and this is a matter of fundamental national importance in the interest alike of the health of the cattle and of the children of this country—on nondescript farms, permanent grass farms, or on ley farms? Where is most of the permanent grass of the country, and where is the best and where the worst—on nondescript farms, or on permanent grass farms? ‘These are all essential facts to be known in the formulation of a long-term national policy for agriculture. The facts are only on the land, the agricultural statistics cannot give anything approaching a full answer to any one of these questions. ‘The answer to these questions, and to equally important questions connected with facilities at the farmstead and over the fields (watering, drainage, and the condition of fences), can only be given by 4 Rice Williams (see ‘ The Growing Danger of Lime Depletion in Welsh Soils,’ Welsh J. Agric., 1937) has estimated that the permanent grass and arable land of Wales alone require at least 14 million tons of lime to bring the lime status to a satisfactory level. The distribution of lime for England and Wales together under the Land Fertility Scheme has not, up to date, been materially in excess of one million tons. M.—AGRICULTURE 251 ‘a properly conducted survey carried out over the whole country and on a uniform plan. Map also the type or class of all the rough grazings and permanent grass (in a manner broadly similar to the survey of Wales recently undertaken by my department), and map the ploughability of the several fields: then, and only then, should we know where we stand. To conduct such a survey would be a relatively simple matter. To my mind, until such a survey is put in hand, and the lessons of the same— cruel and bitter the lessons will be—duly digested, there is little hope that the country at large will realise either the deplorable condition of our acres or their immense potentialities. The first necessity from all points of view—that of the statesman, the townsman, farmer and countryman, in short, that of the nation—is literally and in fact to put rural Britain on the map. Only when rural Britain is on the map shall we be able amongst other matters to decide where in the national interest it is desirable to extend arable farming, and where ley-farming, and where it may be necessary or permissible to tolerate nondescript and permanent grass farming. Having discussed systems of farming and levelled certain well-founded criticisms against nondescript and permanent grass farming, I am now in a position to unloose a whole barrage of criticism against permanent grass as such: and note this, the case for ley-farming is implicit in almost every word of just criticism that can be levelled against permanent grass. My criticisms of permanent grass are general and particular; here are my general criticisms. The psychological influences of permanent grass go much further than I have already indicated ; of course there are clever managers of permanent grass, but I doubt if even the best practitioners are on a par with the most proficient arable and ley farmers ; while speaking generally, the standard of management of permanent grass, I should say, stands to the management of arable land, taking the country as a whole, as certainly not more than 60 (and probably hardly as much as 40) to 100. Leys as long as they continue to be managed as such are almost invariably managed better than permanent grass; they are both easier to manage properly and the inducement so to manage them is greater. My next general criticism is that of the veterinarians who are telling us with a voice that becomes daily louder and more united that permanent grass harbours many of the organisms of disease. My next, because as I have already said an enormous proportion of our permanent grass is in urgent need of lime, a need that becomes ever more serious in view on the one hand of extended milk production, and on the other of the movement in the direction of rearing and slaughtering increasing numbers of young animals. There is only one correct and entirely satisfactory way to apply lime, and that is under the plough, and I think this fact alone is sufficient to condemn not thousands, but at the very least three million acres of ploughable permanent grass, mostly quondam arable, in England ; in Wales to my own certain knowledge it is enough to condemn something over 700,000 acres. My last general criticism of permanent grass is that good young grass properly conserved can be made of immense value to help out the winter 252 SECTIONAL ADDRESSES ration. Grass silage (and probably dried grass also) is bound eventually to come into its own. Bad grass cannot, however, make good silage or good dried grass, while everything is to extend the season over which it is possible to dry grass and make silage—special purpose leys can help enormously to this end. My particular criticisms of permanent grass, considered as grass, are these. Even the best permanent grass is far too weedy and much more weedy than first-class leys, and the best permanent grass has a shorter growing season than can be arranged for by a sequence of good leys. Exceedingly productive leys can be maintained on soils incapable of holding and incapable of being made to hold good permanent grass. I want first to say a little about weediness, and this will lead naturally to the considerations around which the strongest case for ley-farming on grounds of pure husbandry is to be made. Weediness makes for uneven grazing—witness, for example, the effect of buttercups ; it therefore makes for a waste of valuable material ; it also makes for an uneven spread of urine which cannot be mechanically rectified. Because of this, and for another reason now to be explained, weediness or any tuftedness in a pasture reacts against the enhancement of soil fertility, as well as causing the waste of edible material. My ‘other reason’ is that herbage returned to the soil through the animal, provided the lime and phosphate status of the soil is maintained at a proper level, leads to greater soil enrichment and productivity than when such herbage is allowed to rot back, a fact which has been shown by numerous experiments conducted at Aberystwyth,° and which tends to add emphasis to the teaching of our own and other experiments, as, for example, those of Mr. Martin Jones, on the profound influence of night paddocking and of any even slight robbing of Peter to pay Paul. These experiments, coupled with observations over a great number of years, particularly striking phenomena now presenting themselves on the lands where we are conducting our Cahn Hill experiments, force the conclusion upon me that urine has a virtue greater than is fully appreciated, and a virtue that reveals itself on land no matter how generously manured with what have come to be regarded as standard dressings of CaPKN. Consequently any system of grassland management, or for that matter of farming, that does not make the best use of what Mr. Bruce Levy of New Zealand has so aptly, but possibly one-sidedly, described as stock nitrogen, is open to grave criticism. Because of weediness, tuftedness and uneven grazing, and of herbage never converted, and because of night paddock and quasi-night paddock effects, stock nitrogen is wasted, or uneconomically distributed, to a far greater extent on permanent grass than on leys; it is so wasted, and often to an exaggerated extent, on even the best fatting pastures, and particularly so when watering arrangements are ill arranged. The matter, however, goes much further; the fertility accumulating under the best grassland (permanent grass and leys alike) becomes in excess of what can be cashed from the grass-clover covering. All very old- 5 Experiments now in progress at the Welsh Plant Breeding Station, and see R. G. Stapledon, ‘ The Improvement of Grassland,’ Journal of the Bath and West and Southern Counties Society, 1937-38. M.—AGRICULTURE 253 sods become in effect, and to a greater or lesser extent, pot-bound, with the result that the plant covering is incapable of reacting in full measure to the inherent fertility of the soil, while to plough, aerate and lime (where necessary) is to give life to favourable biochemical changes and further to enhance the productivity of the soil. The best grassland holds within itself an immense store of arable potentiality, while the soil rejuvenated by ploughing and aeration, even after yielding several white straw or other crops, can be put back to ever better and better grass. That is the experience of every competent ley-farmer, and ley-farming is creeping into ever better and better permanent grassland. To plough up an old sod full of white clover, and one that has carried an abundance of stock, and therefore which has been well impregnated with stock nitrogen, and to harrow lime into such upturned sod, is to make and spread a compost at one operation. This, in short, is to mix with the soil three essential ingredients, vegetable and animal residues, and lime, and under conditions most conducive to favourable biochemical activity. It is the arable or crop-producing attributes of sod that I maintain constitute the strongest case for ley-farming, for without the intervention of cropping the full fertility value of superb sods can never be cashed.® At the other extreme—the poorest soils—there is nothing to match the continued ploughing down of sod, accompanied by adequate liming and phosphating, to build up fertility. In my own experiences of land improvement gained on what must be some of the poorest soils in Britain, as well as on soils of great inherent virtue, I have been astonished at the progressive improvement in sward and carrying capacity attained when three or four four-year leys have been ploughed down in succession (each sown on the upturned sod of its predecessor) without the interven- tion of a removed nurse crop or of a hay crop. The sequence here is all grass, all grazing and stock nitrogen the whole way, the plough being called in only to assist in compost-making and to ensure adequate ad- mixture of lime, phosphates, organic residues and soil, and to prepare the way for the sowing of the sequential leys. By the adoption of this pro- cedure over a sufficient run of years it is possible to bring land of a most unpromising character into a condition capable of maintaining a rotation balanced between leys and white straw and other crops. There is nothing new in the idea of sowing down immediately on the upturned sod, just as there is nothing new in the idea of ploughing up grassland as a means of improving it. Marshall as long ago as 1789 remarked, ‘ Old pasture lands overrun with ant-hills and coarser grasses are not easily reclaimed without the powerful assistance of the plough.’ The idea of the all-grass rotation perhaps, however, has an air of novelty about it ; wild white clover as a commercial commodity is comparatively novel; cheap phosphatic manures are comparatively novel; the tractor and modern implements are a recent novelty, and more recent are the ® It is true that it is sometimes difficult to utilise the richest sod to the best arable advantage because of wireworm and the lodging of cereal crops. Much remains, however, to be achieved in the direction of the breeding of short stiff- strawed cereal varieties, while in so far as cereals are concerned wireworm is not so destructive after properly managed leys as after permanent grass. 254 SECTIONAL ADDRESSES improved and leafy strains of grasses—all these taken together, if they are to be used to best advantage, must inevitably spell novel rotations. One of the greatest merits of improved technique based on modern facilities for putting down leys on upturned sods, and without resort to covering crops, is that by the periodic adoption of this method (that is to say, as and when necessary) the farmer is enabled to take his leys around the farm sufficiently quickly and before there is any sward deterioration, and in sympathy with the lime demands of his animals and the lime requirements of his soil. It is somewhat remarkable that so little exact experimental or statistical evidence exists for comparing the yield of leys, either in grass, milk or meat, with permanent pastures on similar soils and under precisely comparable conditions. We have Mr. Roberts’s evidence from Bangor,’ which is in favour of the ley, and not a little evidence from Aberystwyth, also in favour of the ley.8 Evidence from grass less favourable to the ley has also been brought forward by various authors. The most con- vincing evidence, however, is the performance and experiences of competent practitioners in the art of ley-farming, and thus the results of investigations and inquiries conducted by Mr. John Orr, lately of Manchester University, are particularly informative and are wholly in favour of the ley.® At present I am engaged upon collecting the material for writing a book on ley-farming. As a preliminary I sent out a questionnaire and have had a most helpful and gratifying response from farmers. ‘The evidence from the replies received is overwhelmingly in favour of the ley, great stress being laid on the improved quality and stock-carrying capacity of the ley grass compared to the quondam permanent pasture, and the extended grazing season provided by the leys. The leys would seem, however, to have justified themselves not only in an extended grazing season, but by virtue of giving grass at periods within the grazing season proper when owing to weather or other conditions grass is liable to go short. Thus Major Dugdale of Llwyn, Montgomeryshire, who is rapidly and methodically (at the rate of about fifty acres per annum) converting the permanent grass of his farm into a sequence of leys by the methods I have discussed, informs me that during the early and unprecedented drought of this year the leys were invaluable, ‘and thanks to them my ewes and lambs which had a turn at them all have done better than usual and have not suffered from the drought.’ Mr. R. L. Muirhead, of Borsdane Farm, Westhoughton, Lancashire, who is well known for his enterprise in ley-farming, speaks equally highly of the value and performance of his leys during the past critical months, and particularly interesting is his remark that ‘the younger fields stood up to the dry conditions better than the others, and the youngest of all (sown 7 E. J. Roberts, ‘I. The effect of wild white clover on the live weight incre- ments from a temporary pasture. II. A comparison of temporary and permanent pasture,’ Welsh J. Agric., Vol. 8, pp. 84-93 (1932). E. J. Roberts, “Comparison of (a) an old with a temporary pasture and (b) two temporary pastures, from oné of which wild white clover had been omitted at seeding down,’ Welsh J. Agric., Vol. II, pp. 132-9 (1935). ® See R. G. Stapledon, The Hill Lands of Britain, London, 1937. ® See John Orr, ‘ Grass and Money,’ Scot. J. Agric., Vol. 20, pp. 31-40 (1937). va M.—AGRICULTURE : 255 last August) with Italian rye-grass has done best of all.’ 1° Mr. Wilks, of Whartons Park, Bewdley, Worcestershire, who after prolonged attempts at improving the poor permanent grass on his farm is now rapidly getting into the ley system, says that during last back end (1937) the whole of his grazing came from leys and newly grassed areas. The old permanent pastures did not recover from the late summer and early autumn drought of that year, and the leys carried all the stock from July onwards. During the drought of this spring his position was never difficult, the maiden leys providing an abundance of good pasture, and these after being grazed into May will be mown for hay. In a recent letter to me Mr. Wilks concludes with this peculiarly significant statement : ‘An interesting sidelight is that the arable crops on land recently ploughed out have stood the drought much better than those on the stale old arable . . . the whole thing is complementary and balanced.’ The experiences of Colonel Pollitt, of Harnage Grange, Cressage, Shropshire, are in keeping with those of Mr. Muirhead and Mr. Wilks. Colonel Pollitt has also sown out early in May without a nurse crop and has been able to start serious grazing (ewes and lambs) in the first week of July, thus obtaining valuable young grass at what is often a critical time of the year. On a field thus treated Colonel Pollitt also wintered cattle continuously from November 1 to May 1, and he informs me that there was no poaching except at the gate. The ley, furthermore, affords great scope for special treatment with a view to providing grass when it will be most wanted. Ley grass put up for the winter carries green and protein-efficient into February, March and April altogether more effectively than does permanent grass, and this is perhaps one of the greatest merits of the ley, and a merit which by virtue of further research in plant breeding in the direction of producing winter green and winter growing strains is likely to become increasingly pronounced. The employment of different seed mixtures with a view to giving grass more particularly at different and explicit periods of the year affords additional scope to the ley-farmer. Thus at Aberystwyth we have found that a mixture consisting predominantly of Danish meadow fescue and Aberystwyth S. 48 timothy gives exceptionally good grazing during July and August. On this and similar points there is, however, need for greatly extended investigation. I have now made my case for ley-farming, but I am not at present claiming that all permanent grass should be brought under the plough; before that claim could be substantiated we want a proper survey and a great deal more experimenting. Apart from steepness, boulders and such like, low rainfall and heavy clays present their special problems. As to the clays, the fact that it is a perfectly sound procedure to re-grass 10 This performance of Italian rye-grass is on all fours with results obtained for the past four years with Italian rye-grass at the farm of the Cahn Hill Improve- ment Scheme, 1 See R. G. Stapledon, ‘Immature Grass and Young Swards.’ Part I, /. Minist. Agric., Vol. 44, pp. 317-29, July 1937; Part II, J. Minist. Agric., Vol. 44, pp. 442-9, Aug. 1937. 256 SECTIONAL ADDRESSES straight away on an upturned sod makes a lot of difference, as does the soundness and feasibility of the all-ley rotation, while we have the tractor and modern implements. To make it possible to establish leys without undue risk of failure on the heaviest soils is to-day, I feel convinced, only a matter of sufficient experimenting as to ways and means. The same is, I am sure, largely true of establishing leys in regions of low rain- fall. Mr. Mansfield seems to have no difficulty in establishing excellent leys in this district not remarkable for its high rainfall, while everybody who farms on something akin to the four-course rotation after all establishes leys. What is wanted in order to establish a foolproof and almost weather- proof technique is much more experimenting. ‘There is a right date to sow for every district, while in the driest areas I doubt the wisdom of sowing under a nurse crop, for the quicker growing cover crop must compete exaggeratedly with the slower growing seedlings for what little moisture there may be. It may be unwise under such conditions to include even Italian rye-grass in the mixture, for this is always by far the quickest grass seedling to get off the mark, while it would seem to be of supreme importance to obtain a scrupulously clean seed bed, and to bring in the mower at the first sign of weeds gaining dominance. The successful grassing of new golf courses in regions of low rainfall, I think, holds valuable lessons for the would-be ley-farmer—‘ put as little as possible to compete with the grasses you ultimately want’ would seem to be the teaching. I would again emphasise that it is not sufficiently realised that a ley sown without a nurse crop very soon starts earning money on its own account, and where 4-6-8-10 year leys are at stake it is poor economy to jeopardise the whole for the sake of a preliminary cash crop. I cannot conclude my address without a little more detailed reference to the ley itself. The chief points at issue are how to establish it, what , to sow and how long to leave it down. Not one of these questions can be answered in general terms, but there are in each case fundamental principles at stake. The fundamental principle relative to duration is the fertility attributes of the sod. From that point of view, and con- sidering alike soil condition and manurial residues, my friend Prof. Robinson (1937) in the informative letters he has so kindly, and if I may say so, attractively, written for my major enlightenment, would seem to agree with me that there is everything to be said for the four-year ley, ending, as I would wish to insist, with at least two years of honest hard grazing, with urination and spread of white clover. ‘The general principle here is ‘to plough down the sod before it has by one jot deteriorated.’ It has, however, to be remembered that grazed swards do not leave behind them a sod with a deep-going root system; hayed swards develop a deep-going root system. In the interest of general fertility and soil condition I hold that it is sound practice, ever and anon, to plough down sod with a deeply penetrating root system. Now from the point of view of hay production, the highest yields are obtained from leys in their first and second harvest year—that is to say, as long as late-flowering red clover lasts. In general my view is this, that the best practice founded on scientific principles would be to employ 1-2 year leys for hay and M.—AGRICULTURE 257 4-6 year leys for grazing only. The three-year ley is rather like the dual- purpose animal. Although it is a brave southerner who would criticise Scottish practice, I am inclined to criticise excessive dependence on dual-purpose (hay-grazing) three-year leys. I would rather have a sequence of 1-2 year deep-rooting-hay leys following after four-year- white-clover-replete-shallow-rooting-grazing leys. ‘This procedure would give more hay, more grazing and more fertility. With apologies to Aberdeenshire, that is my considered opinion. In any event my criticism of the very best practitioners of ley-farming is that they do not use leys of different kinds for different purposes, and do not rotate all the different sorts of leys after each other all round the farm to anything like a sufficient extent, for it is thus, and only thus, that all-the-year-round grazing is to be obtained. ‘This is too large a subject to discuss in detail here, but it is one demanding much thought and much agronomical research. In passing I might say that in my view no problems so much as those of grassland demand prolonged and large-scale agronomical investigation. I would wish to distinguish between, on the one hand, agronomical re- search, and on the other, scientific research as normally understood and conducted. The major aim of agronomical research, which is essentially field research, is to study all the factors which are operative at once and together, and in their natural interplay, for ‘ nature is a theatre for the inter-relations of activities.’ Such a procedure, it may be said, is im- possible, or at least unscientific. It is certainly not impossible, and if it is unscientific it will yet remain agronomical, and many of the problems of agriculture are more likely to be solved, shall I say, by agronomical investigation than by scientific research, while nearly all the results of scientific research have to pass through the sieve of an immense amount of agronomical investigation before they can be made useful, and in some cases perhaps before they can be other than positively dangerous to the practitioner. The technique of agronomical research entails a great deal more than blindly following all the elaborate rules and regulations laid down by the statisticians; indeed, such rules and regulations are of no fundamental significance in the proper planning of an elaborate series of field experiments. They are sometimes, but by no means always, useful in the actual placing of plots on the ground, and they are some- times essential, but are by no means always necessary, in the examination of quantitative data. One effect of the modern glorification of statistical methods has undoubtedly been a tendency to obscure the wood for the trees, to concentrate on the part, often an isolated part (yield, for example), instead of the whole ; and, worse still, to fill the agronomist with a medley of complexes and inhibitions which have reacted adversely on the develop- ment of a technique adequate to solve a large number of the problems that can only be solved by highly complicated field experiments. Many agronomists are almost too frightened to set up the sort of experiments their experiences teach should be set up, because they are timorous lest the data could be made amenable to statistical analyses. Agriculture would have been the gainer if the agronomist had never been taught to be timorous, and if he had plodded away undeterred and undismayed at the details of his own technique, when by now perhaps he would have K 258 SECTIONAL ADDRESSES been able to justify his claim that what is primarily wanted to-day is enormously increased facilities for the conduct of field experiments in contra-distinction to field trials and demonstrations. That at least is my claim, for I claim to be an agronomist, and in that capacity one who has been responsible for the setting up of hundreds of weird little field experiments involving in all literally thousands of plots. As always, however, the greatest and the final hope is the farmer him- self, for he at least is untrammelled by the technique of science, and is not a slave to the fashions current in science, while his major training is not in collecting data, but in the gentle art of unadulterated observation. Just because, therefore, of the immense accumulation of scientific know- ledge, so much of it but half digested in the practical sphere, never so urgently as at present has there been such a necessity for an abundance of well-informed, originally-minded and affluent pioneers, men willing and eager to transgress against every canon of good husbandry, and to explore, and almost de novo, the whole field of rotation of crops, and the whole idea of rotation of pastures of different types and of stock over the surface of the farm. This has been a long digression ; it has, however, been relevant to my theme, and it has been on a question of undeniable importance and about which I think I am entitled to express opinions. I will now return to the ley. Grazing management affects the permissible duration of the grazing ley to a marked degree. Thus he who bails cattle or folds poultry can keep his leys down much longer than the ordinary farmer who thinks he is grazing intensively, but in fact is doing nothing of the sort; only the close folder, or the tetherer, really grazes intensively, and by intensively I mean without waste of any sort. But even under the cleverest manage- ment sooner or later the sod will begin to become pot-bound, and according to soil type, bent, soft brome, Yorkshire fog, weeds or moss will proclaim the need of the plough and a new start. What to sow and how to establish are in the main twin problems— twin to this extent, that what to sow is determined much more by every shade of after-management that it is proposed to follow than by soil type ; the trouble here is that agricultural chemistry has such a terribly long start of agricultural biology. Grassland, like every crop the farmer handles, is the plaything of soil, climate and the biotic factor ; with grassland the master factor is the biotic—that is to say, what man himself does with his animals. One, and the most obvious, example will suffice— the use and abuse of Italian rye-grass. Italian rye-grass is essentially a grazing grass ; if allowed to grow away in a hay mixture it will smother and depress other and higher yielding hay grasses. It should therefore only be included in hay mixtures when such mixtures will be grazed long into the spring or early summer, and when after a small and herby hay crop aftermath is of prime importance. Italian rye-grass is of its greatest value for sowing with grazing mixtures put down on an upturned sod. The aim here is two-fold ; firstly, to bring treading feet and urine on to the developing sward as soon as possible—this is the function of the Italian rye-grass; and secondly, to encourage the spread of wild M.—AGRICULTURE 259 white clover as rapidly as possible—this is the combined function of light (keeping the Italian rye-grass in reasonable subjection), the treading feet and the urine. The so-called indigenous strains! Badly called, and I am afraid that I have been largely responsible. In the few words I have to say on this subject I will confine myself to the Aberystwyth bred strains, for here at least I am talking about something definite and about which I myself at all events may be supposed to know something. For the sake of brevity I will lump the findings of all our experiments, and of all my own experi- ences, and those of my colleagues, into a single short paragraph. For the ordinary three-year hay-pasture ley on medium-good soil, postulating the inclusion of wild white clover and good urination, the Aberystwyth pasture and pasture-hay strains are by no means an absolute necessity, but in reasonable amount-(say up to about one- fifth to one-third of the rye-grass, cocksfoot and timothy contribution) I recommend their inclusion for the sake of the extra back-end grazing they will give, and to add leafiness to the hay crop. For leys of four years and longer duration, I believe a contribution of Aberystwyth pasture or pasture-hay strains of not less than one-third of the con- tribution of rye-grass, cocksfoot and timothy always to be justified. On really poor soils and for re-grassing derelict grasslands there can be no question as to the absolute necessity of including the pasture and pasture-hay strains. On our Cahn Hill lands, and elsewhere, we have made quite remarkable swards by using such strains wholly, or up to two-thirds of the mixture, where with the non-pedigree bred strains it has been impossible to establish a sward capable of maintaining itself for more than twelve months. You will note I have talked explicitly of the Aberystwyth pasture and pasture-hay strains. We have now early hay strains coming on such as Dr. Jenkin’s S. 24 perennial rye-grass, his S. 51 timothy, and my own somewhat modified S. 37 cocksfoot, which will I think vie with the ordinary seed of commerce in earliness and bulk during the first and second harvest years, and which are much more leafy. The matter here will turn almost wholly on the relative cost of the pedigree and non-pedigree seed, for manifestly an expenditure on seed that would be abundantly justified for a four- to twelve-year ley might not be an economic proposition for a one-, two-, or three-year ley. If, however, the hay strains ultimately prove themselves to have sufficient virtue they are bound in due time to replace the ordinary commercial strains, and in fact by a process of substitution to become in effect the ordinary commercial product. This I think will be the destiny anyway of Dr. Jenkin’s S. 24 rye-grass, for as well as being early and relatively leafy it gives much better July-August grazing than the ordinary Irish and Ayrshire rye-grass. In this matter of the Aberystwyth strains, however—such is the deeply penetrating influence of psychological factors—I can have no cause for complaint if you deem it well to regard me as a prejudiced witness, but if you so regard me, please yourselves be sufficiently broad-minded to come and see our trials, or go and have a look at one of those which with the help of the Royal Agricultural Society we are setting up in various 260 SECTIONAL ADDRESSES English counties; or better still, experiment for yourselves under your own, your very own, scheme of management. It may be that management in some cases is so superbly good that it hardly matters what a man sows, while in others it may be so supremely bad that no proper use can be made of a good thing when a man has got it. I am afraid I have adopted an unusual course in my approach to my subject ; I have not followed normal practice, for instead of reviewing the data and evidence available I have in effect reviewed my own reactions to the implications of the work with which I have been connected for the past twenty-five years and more. Perhaps I need not apologise for this, for after all facts and data are of no practical use until people grapple with the practical implications. Instead of my ‘ facts ’—and scientific ‘facts’ are not always correct—I have put my grapplings before you, that is all, and if justification is necessary I think sufficient justification is the admittedly deplorable condition of a huge acreage of this country, the dilapidated condition of many of our farms and farmsteads, and the therefore necessarily backward state of much of our farming. Two needs seem to me to be crystal clear: first, the conduct of a survey on the land—and I believe every agricultural scientist, though perhaps not every farmer and every economist, would agree to ‘on the land’ somewhat on the lines I have suggested—and then the ways and means of getting the plough into the grasslands that the survey conclusively proves ought to be ripped up. Working capital, and the correct expenditure of that working capital, is in the last resort the only solution for our derelict and quasi-derelict acres. I like the American idea of loans with a working plan; of loans with advice. I do not believe that the history of the years since about 1894 show that the spasmodic periods of agricultural prosperity that have on occasion intervened have been responsible for a great deal of land im- provement, or for a proportionate improvement in the equipment necessary for productive farming. Prosperity as such in agriculture, as in industry, is to a large degree a function of equipment, for without the necessary equipment it is impossible to farm economically, just as it is impossible to manufacture economically. Again, it is unreasonable to expect that a man devoid of working capital, and probably the son of a man similarly devoid, should have all the knowledge of how best to farm, and particularly of how best to improve land (in which art he will necessarily have had no sort of experience), in sympathy with adequate working capital suddenly provided for the purpose. Advice, and some measure of control, must necessarily go with credit facilities, and in so far as breaking up grassland is concerned I like still better the American idea of group loans, and of a ‘ master borrower.’ The ‘ master borrower’ in this case would be set up as a contractor with tractor and necessary equipment to break up the grass- lands, for it is important to remember that ploughing up of this sort is essentially tractor work, that it interferes with the normal routine of an ill-equipped farm, while tractors are to all intents and purposes non- existent in many of the districts where wholesale ploughing up is most necessary. My own experiences are interesting in this connection. We want 9 M.—AGRICULTURE 261 tested the desire for contracting last year, and had three times as many applications as we could fit into the acreage we could do, while now, and because of the demand our work has created locally, a lorry contractor in the neighbouring village has acquired a tractor, and is fully engaged on contract ploughing. I like also the American idea of being boldly eclectic and scheduling particular districts as being eligible for their rehabilitation loans; indeed, I was foolhardy enough to make a suggestion very much on these lines in my book The Land Now and To-morrow. ‘There are innumerable districts that should be similarly scheduled and similarly helped in this country, but always through financial help cum technical advice terminat- ing in an agreed working plan; and here again my own experience comes to support my contention, for in those cases where we contracted we only did so when the farmer agreed to follow all our advice as to subsequent operations, manures and seeds, to the letter, and in all cases the farmer has done so, and demonstrably to his own advantage. The breaking up of derelict grassland is to be helped forward not only by loans, but by a reorientation of such working capital as the farming community possesses, and also, I think, by a reorientation of the monetary and other arrangements existing between landlord and tenant. Ley-farming in my view affords great scope for such reorientation, for it would make possible, and on a general scale, a variety of methods of share farming. For example, one might conceive of a mechanised wheat grower operating over a large number of neighbouring ley farms on a share basis ; another man on a share basis might be running the poultry, the proprietors themselves being primarily interested in the adequacy of the rotation and farming operations, and possibly in one major product— milk, shall we say? By this means farmers should achieve a better return on such working capital as is available, and also the nation should achieve a more balanced specialisation between farming qua farming and com- modity production and disposal. Landlords themselves with advantage could often think out methods of sharing-in with their tenants, and ley- farming opens many avenues of approach to such sharing-in, but in any event it behoves the landlords of many districts to be alive to changing times, and to be ready for the day—not, I think, far distant—when better tenants will be found for farms which are going concerns on the ley-farming basis than for those which are nondescript or permanent grass. It may thus prove to be a wise policy to adjust leases, and even financially to assist purposeful tenants towards that system of farming which will accord best with the trend of national and international events. Let me insist, in conclusion, that the affairs of agriculture, slowly moving as they necessarily must be, are ill adapted to respond to the dictates of any immediate expediency, for expediency is ever shifting, and at the best ‘is the mere shadow of what is right and true.’ To be ever prepared for change in a world that is ever changing can be the only possible basis for a sound agricultural policy for this country, since we are so peculiarly liable to be crucially affected by happenings beyond our own control, beyond our own jurisdiction and beyond our own borders. 262 SECTIONAL ADDRESSES REFERENCES. Orr, John. 1937 Scot. J. Agric., 20, 31-40. Rice Williams. 1937 Welsh J. Agric. Roberts, E. J. 1932 Welsh J. Agric., 8, 84-93. —____———_ 1935_-Welsh J. Agric., 11, 132-9. Robinson, G. W. 1937 Mother Earth, London. Stapledon, R. G. 1937-8 Journal of the Bath and West and Southern Counties Society. —_—__—_—— 1937 The Hill Lands of Britain, London. —_—_—_—_—_———._ 1937a__ J. Minist. Agric., 44, 317-29. ——————— 1937b) Je Mimst. Agric. AS, 442-9. ———__——— 1938 The Fortnightly. REPORTS ON THE STATE OF SCIENCE, ETc. SEISMOLOGICAL INVESTIGATIONS. Forty-third Report of the Committee of Seismological Investigations (Dr. F. J. W. Wuippie, Chairman; Mr. J. J. SHAW, C.B.E., Secretary ; Miss E. F. Bettamy, Prof. P. G. H. Boswett, O.B.E., F.R.S., Dr. E. C. BuLiarp, Dr. A. T. J. Dotyar, Sir FRanK Dyson, K.B.E., F.R.S., Dr. A. E. M. Geppes, O.B.E., Prof. G. R. Gotpssroucu, F.R.S., Dr. WitFreD Hatt, Mr. J. S. Hucues, Dr. H. Jerrreys, F.R.S., Mr. Cosmo Jouns, Dr. A. W. Ler, Prof. E. A. Mine, M.B.E., PRio:, Prof. H. H. Puasxetr, F.RiS:, Prof. H.C. Puumner, F.R.S., Prof. J. Proupman, F.R.S., Prof. A. O. RANKINE, O.B.E., F.R.S., Rev. C. Rey, S.J., Rev. J. P. Rowxanp, S.J., Prof. R. A. SAMPSON, F.R.S., Mr. F. J. Scrasz, Dr. H. Suaw, Sir FRANK SmiTH, K.C.B., C.B.E., Sec.R.S., Dr. R. SroneLzy, F.R.S., Mr. E. TILLoTsON, Sir G. T. Watker, C.S.I., F.R.S.) MEETING OF THE COMMITTEE. THE Committee met once during the year, on October 29. The annual grant of £100 from the Caird Fund was allocated to the University Observatory, Oxford, for work on the International Seismological Summary. Expenditure on various objects from the Gray-Milne Fund was author- ised. Dr. E. C. Bullard gave a short account of the methods adopted in America in the application of seismological methods to the investigation of the thickness of the strata overlying the continental shelf. In view of the fact that research on these lines was likely to be undertaken with the support of the Royal Society, it was decided that no action on the part of the British Association was necessary. Dr. Dollar gave the Committee an account of the British Earthquake Inquiry, which he was organising, and it was decided to give some financial support to the organisation. THe Gray-MILNE FunpD. The accounts for the year are reproduced below. The income of the fund has again improved owing to an increase in the dividend paid by the Canadian Pacific Railway. Expenditure on the Milne Library includes the purchase of Dr. Davison’s book, Great Earthquakes. Gray-Milne Fund. Le MS Sie hele Sees Gi Balance, July 1, 1937. 187 4 2 Milne Library Guo tO Trust Income . - 65 4 10. Insurance . : : 15.0 Bank Interest . é I 110 Printing (Bullen’s Con- version Tables) : ry, ot) 9) Jaggar Shock Recorder 21 0 o British Earthquake In- quiry. : Tou) O Balance, June 30, 1938 204 7 10 £253 10 10 £253 10 10 es See 264 REPORTS ON THE STATE OF SCIENCE, ETC. SEISMOGRAPHS. The six Milne-Shaw seismographs belonging to the British Association have remained on loan to the seismological stations at Oxford (2), Edinburgh, Perth (W. Australia), and Cape Town (2). During the year a Jaggar shock recorder has been made for the Com- mittee at Bristol under the supervision of Dr. C. F. Powell. This instru- ment is to be set up at Dunira, near Comrie, the village in Perthshire which is famous for the prolonged series of minor earthquakes in the last century. It may be recalled that a Committee appointed by the British Association set up seismometers, in Comrie and near by, with which to measure the amplitude of earthquake waves. Eight of the seismometers were inverted pendulums, designed by Prof. J. D. Forbes and ‘ working on the principle of the watchmaker’s noddy.’ These instruments were affected by the local earthquakes on two or three occasions, but they were not sensitive enough to be disturbed by the majority of the shocks. After an interval from 1844 to 1867 the Committee for registering earthquakes in Scotland was reappointed. Only one of the original seismometers was then in use, the ro ft. inverted pendulum in the church tower at Comrie. The Committee decided to adopt a suggestion of Mallet’s and provide a set of small cylinders which were to topple over when an earthquake occurred. A special hut, which still stands in the grounds of ‘ Dunearn,’ was allotted to the cylinders, but it is believed that no earthquake ever bowled them over. As far as is known none of these primitive seismometers survives in Perthshire, but there is in the Royal Scottish Museum at Edinburgh one of Forbes’s inverted pendulums. It is hoped that the new shock recorder will eventually provide some evidence as to the nature of the earth-move- ments in the Comrie region. The Committee is indebted to Mr. W. G. Macbeth of Dunira for allowing the installation of the instrument, and to Mr. White who is undertaking to operate it. GEOCENTRIC CO-ORDINATES. Owing to the progress in the precision of seismological observations, and in the accuracy of the tables with which the observations can be com- pared, it has now become desirable to take into account the ellipticity of the earth, both in locating the epicentres of earthquakes and in discussing the behaviour of seismic waves of different types. It was pointed out by Gutenberg and Richter, in 1933, that this could be done most readily by using geocentric co-ordinates instead of the ordinary geographical co- ordinates. Investigations by Dr. Jeffreys and by Dr. Bullen have confirmed the desirability of this refinement. Tables giving for each observatory rectangular co-ordinates on the new system, or rather the direction cosines of the radius from the centre of the earth, are required. The Committee enlisted the help of Dr. L. J. Comrie, who has had the necessary calculations made and is seeing the resulting tables through the press. These tables will be published in the autumn. 4 Geographical angular distances have been employed hitherto in the International Seismological Summary, as in almost all other work on earthquakes ; 7.e. the angle between the verticals has been regarded as giving the distance between two points on the globe. A method of utilising the data without recomputing the distances ab initio has been devised by Dr. Bullen. Tables computed by Dr. Bullen for use in the application of this method have been published by the Committee, with an Introduction by Dr. Jeffreys. SEISMOLOGICAL INVESTIGATIONS 265 BRITISH EARTHQUAKE INQUIRY. The Organisation for the Collection of Seismic Data. Through the agency of an organisation developed since October 1935 to collect detailed non-instrumental data about earthquakes disturbing the British Isles, twenty-one undoubted earth tremors, thirteen doubtful tremors, six land-subsidences and the seismic effects of three explosions have been investigated to date, and material gathered for a catalogue of quakes noticed between January 1, 1916 and October 1, 1935. At present the personnel of the organisation involves 287 permanent voluntary reporters, recruited from forty-four counties in Great Britain and the Irish Free State, and others in the Channel Islands, each of whom notifies Dr. Dollar at Emmanuel College, Cambridge, immediately any earth tremor disturbs the locality of the reporter concerned. Often these reporters assist in the subsequent distribution and re-collection of question- naires relating to effects of such a tremor. Their number has been in- creased by 221 since July 1, 1937, and additional help has been obtained from officials in Government, University and private seismological ob- servatories, the British Broadcasting Corporation, the Trinity House Corporation, meteorological observatories and schools, as well as from the Press Association and daily newspapers. The greatest part of the information is gathered by questionnaires, more than 95 per cent. of which are dispatched from Emmanuel College. In June 1938 a third and abbreviated edition of the questionnaire was issued; this has proved of greater general utility than previous more elaborate editions. The Seismic Data gathered between Fuly 1, 1937, and Fune 30, 1938. Since July 1, 1937 details have been collected about the following tremors felt in the British Isles : Earthquakes : July 9, 1937 i ‘ . Walsall, Staffordshire. July 20, 1937 i : . Perthshire. September 8, 1937 3 . Horsham, Sussex. December 4, 1937. i . Comrie, Perthshire. March 21,1938 . ‘ . South-East Edinburgh, Edinburgh. June 11, 1938 ‘ é . Ghent, Belgium. Subsidences and Mine-shakes : September 13, 1937 : . Cudworth, Yorkshire. December 14, 1937 ; . Nelson, Glamorganshire. December 30, 1937 : . Norwich, Norfolk. January 1,1938 . : . New Tredegar, Monmouthshire. Explosions : November 20, 1937 : . Thrapston, Northamptonshire. December 1, 1937 : . Waltham Abbey, Essex. Origins not Established : November 21, 1937 : . Worthing, Sussex. December 6, 1937 ‘ . Tenby, Pembrokeshire. January 29, 1938 . ; . Great Missenden, Buckinghamshire. April 13, 1938 : : . Stepney, London. April 20, 1938 : - . Golders Green, Middlesex. June 18, 1938 : ; . Gilfach Goch, Glamorganshire. (Now being investigated.) K 2 266 REPORTS ON THE STATE OF SCIENCE, ETC. THE BELGIAN EARTHQUAKE OF JUNE II, 1938. During the 12-month period the most important earthquakes originating beneath the British Isles were those of Walsall, Horsham and South-East Edinburgh. ‘These were insignificant, however, in comparison with the earthquake that was centered below Belgium and shook more than 20,000 square miles of country in twenty-nine English counties on June 11, 1938. As a result of appeals for information through the daily press, three wireless broadcasts and the distribution of numerous questionnaires, 856 reports have been gathered about this tremor from 278 towns in England, the Channel Islands, France, and Belgium. Eight reports have been obtained from seismological observatories in Britain and North-west Europe. The tremor was noticed mainly by people at rest indoors. Positions in the upper stories of high buildings were especially favourable. Particularly in the east of the disturbed area at least two phases were distinguished, and the motion was described as being a succession of smooth undulations in an approximately east-west direction, conspicuously free from jerks. ‘The numerous accounts of apparent giddiness may be related to the smooth wave-motion experienced. The only damage on this side of the Channel appears to have been a single fall of a few tiles at Herne Bay, Kent. Appropriately-oriented pendu- lum clocks were stopped in some cases, and in others, liquids were agitated or spilled. Dogs, cats, and birds showed signs of alarm, and two reports suggest that bees in open out-apiaries were so disturbed by the shock as to have been unmanageable for a time. The area over which a sound was heard is ill defined, but does not seem to extend far west of the longitude of London. Generally it was likened to a rumble such as might be produced by the passage of a heavily-laden lorry or train. After-shocks of the Belgian earthquake were recorded at Kew Observatory on the same day at 12.10 and 13.9, and a much larger one on the next day, June 12, at 13.26. Only the last of these was felt in England. It was reported by nine observers. Mutually inconsistent reports of supposed foreshocks and aftershocks were received from about a score of corre- spondents. It is understood that Belgian seismologists place the epicentre of the main shock near Ghent. The best precedent for tremors affecting approximately the same area is the earthquake of April 6, 1580, which caused considerable damage in Kent. The epicentre of that earthquake is thought by R. E. Ockendon, the editor of the recent reprint of Thomas Twyne’s Discourse on the Earthquake, to have been near the Straits of Dover. SEISMOLOGY AT Kew OBSERVATORY. During the year the installation of the seismographs in a new under- ground house was completed. The three Galitzin seismographs record on one electrically driven clock drum, the two Wood-Anderson instruments on another. A description of the installation is being published in a Memoir written by Dr. A. W. Lee. It is satisfactory to be able to note that the disturbances which affected so seriously the utility of the Galitzin seismo- grams in windy weather, and which were attributed to the rocking of the observatory, have no counterparts in the records obtained in the new seismological building which is mostly below ground level. A number of technical points with regard to Galitzin seismographs had to be investigated SEISMOLOGICAL INVESTIGATIONS 267 on account of the introduction of a new way of operating these instruments. Details will be found in Lee’s Memoir. The Wood-Anderson seismographs, which are adjusted with a period of 24 seconds, record the horizontal components of the earth’s movement. An instrument with about the same period to record the vertical component is required. An experimental seismograph of this type was constructed in the Observatory workshop and has been in operation for some months. The special feature is the introduction of ‘ viscous coupling ’ (by means of a plunger working in a cup filled with liquid) between pendulum and mirror. Some promising records have been obtained from recent earth- quakes, but modifications to the instrument will be required before operation is entirely satisfactory. A paper by Dr. Lee, ‘ The travel-times of the seismic waves P and S, a study of data from the International Seismological Summary, 1930 and 1931, is being published shortly as a Geophysical Memoir of the Meteoro- logical Office. SEISMOLOGY IN THE WEsT INDIEs. The series of earthquakes which occurred in 1934 and 1935 in Montserrat led to the despatch of an expedition to that island. Valuable reports on the geological structure of the island and on the distribution of the earth- quake centres were written by Mr. A. G. Macgregor and Dr. C. F. Powell. The Wiechert seismograph and eight Jaggar shock recorders are still in operation in the care of Mr. Kelsick, who is making regular reports on the seismic activity in that island and is also collecting information about shocks which are felt in other islands. From August to November 1937 about forty earthquakes were reported by observers in Dominica. The Royal Society has nominated a West Indies Seismological Committee, and this Committee has under consideration the despatch of an expedition to Dominica. The earthquakes in that island have been less frequent, how- ever, in recent months, and the proposal is therefore in abeyance at present. THE INTERNATIONAL SEISMOLOGICAL SUMMARY. A Note by }. S. Hughes. The International Seismological Summary has now been prepared in manuscript as far as July 1933; January, February and March are in the press, while April, May and June are in process of being finally checked through. The number of earthquakes dealt with in a given period of time remains roughly constant but with a fluctuation which is mainly dependent on the presence or absence of cases in which a long sequence of after-shocks to an earthquake of great intensity occurs in a region well equipped with re- cording stations. Such a case was provided by the Sunriku earthquake of March 2, 1933, origin 39°1° N., 144:7° E., off the east coast of Japan. This earthquake, which is notorious for the devastating tunami it produced, was followed by a‘large number of shocks from the same neighbourhood, but apparently not from a single focus. This interesting series of shocks was worked out in as much detail as possible and a number of different epicentres were determined. It is not claimed, however, that finality has been attained, and the observations, extending over many days, would afford a good subject for special study. Of the earthquakes listed for the month of March 1933, 142 were after-shocks of the series in question. 268 REPORTS ON THE STATE OF SCIENCE, ETC. In the portion of the Summary dealt with during the past year, there are many large earthquakes and numerous cases of deep focus. Notable among the latter are the earthquakes of October 14, 1932, 31°6° N., 13'8° E., where distant records are completely absent, and January 9, 1933, 36°5° N., 70°5° E., where there is a wealth of observations over a range varying in epicentral distance from 4° to 80°. In the former case, the epicentre being in the Pacific to the south of Japan, there were excellent observations of P and S at 40 stations, all within a distance of 11°7°, but there were no observations outside Japan. The focal depth (determined at Tokyo) was 300 km. ‘The other epicentre, which is in Kafiristan near the north-west frontier of India, is one to which 10 deep-focus earthquakes were assigned in the years 1921 to 1930. From January 1933 onwards an attempt has been made to distinguish in the Summary between compressional and dilatational longitudinal waves. For a compressional wave, where the initial motion of P, PKP or PKKP is away from the epicentre, the letter ‘a’ (anaseism) is entered after the reading. If the wave is dilatational, or towards the epicentre, the letter “k’ (kataseism) is used. ‘This notation was adopted by the International Seismological Association at Edinburgh in 1936, the use of the adjectives anaseismic and kataseismic having been proposed by the Rev. E. Gherzi, S.J., as long ago as 1924. If the components of displacement in the onset of P are recorded by the observing station, the direction of initial motion is known, and the dis- crimination between ‘a’ and ‘ k’ can be made after the epicentre has been determined. Particularly useful is the Z component, as an upward initial motion always indicates an ‘ anaseism ’ and knowledge of the position of the epicentre is not required. A good many observatories are already providing in their bulletins the necessary information with regard to the initial move- ment of each earthquake. It is hoped that the practice will be adopted generally. WorK ON TRANSMISSION TIMES AND ON PERIODICITY. By Dr. Harold Jeffreys, F.R.S. The work on southern earthquakes and the core waves, which was in progress at the time of the last Report, has been completed. For PKP only readings at the most reliable stations with vertical component instru- ments were used and the result was a symmetrical distribution of residuals with a standard error of about 2 sec., nearly the same as for P. Accordingly there is a high probability that the dangers of systematic error in PKP have been removed. The summaries have a standard error of about 0-4 sec., about the same as for P at most distances. The times of SKS have also been rendered somewhat more accurate. Some of the earthquakes used were found to show signs of multiplicity. There appeared to have been two or three shocks at the same place, separated by intervals up to 10 sec., and P had been read for the first, and S and SKS for a mixture, usually with a preference for the later ones. This explains most of the ‘ Z ’ phenomenon, leaving no more than can be reasonably attributed to variations of focal depth within the upper layers. Cases where the separation is larger have already been considered by Stoneley and Tillotson and appear to provide an explanation of most of the recorded cases of apparent ‘ high focus.’ A study has been made of the frequency of after-shocks of the Tango (Japan) earthquake of March 7, 1927. They were found to agree with a law, such that the chance of an earthquake in an interval dt is pro- portional to dt/(t — a), where a is near the time of the main shock. Apart MATHEMATICAL TABLES 269 from this the after-shocks appeared to be independent. Search was made for periodicities of the solar and lunar days and half-days, a fortnight and a month, and for any evidence that returning waves tend to stimulate a new shock, but no such evidence was found in any case. It appears that, except within an interval very close to the main shock, after-shocks may be con- sidered as related to the main shock and nothing else. It appears, however, that if data used in testing suggested periodicities include after-shocks, the random amplitudes found would be greatly increased by the dependence of the after-shocks on the main shocks of their series. ‘This makes the events occur in batches, and the usual tests for the significance of an amplitude found by Fourier analysis fail. No alleged periodicity can be trusted if it is based on data that include different series of after-shocks. An analysis of deep focus earthquakes is in progress, in the hope of ob- taining a test of the 20° discontinuity and improvements in the estimated thicknesses of the upper layers and in the times of S at short distances. It _ has been found that the times of P, adapted to a discontinuity and to a continuous time curve that would be consistent with the data of normal earthquakes, would differ by a maximum of about 1°6 sec. in deep ones. This is perhaps just within the range of observability if relevant data can be found. REAPPOINTMENT OF THE COMMITTEE. The Committee asks for reappointment and for the renewal of the grant of £100 from the Caird Fund. MATHEMATICAL TABLES. Report of Committee on Calculation of Mathematical Tables (Prof. E. H. NEVILLE, Chairman; Dr. A. J. 'THompson, Vice-Chairman ; Dr. J. WisHarT, Secretary; Dr. W. G. Bicktey, Prof. R. A. Fisuer, F.R.S., Dr. J. HeNperson, Dr. E. L. Ince, Dr. J. O. Irwin, Dr. J.C. P. Mitier, Mr. Frank Rossins, Mr. D. H. Sapier, Mr. W. L. STEVENS and Dr. J. F. Tocuer). General activity.—Eight meetings of the Committee have been held, in London. The grant of £200 has been expended as follows : £ wisiond: Wages and insurance for computer for forty-seven weeks . 142 9 5 Calculations for Bessel functions of order greater thanone . 45 6 9 Calculations for Airy Integral, etc. . : : : FAM SOUS Secretarial and miscellaneous expenses. 4 : BTL aeIO Personnel.—The Committee has been particularly unfortunate this year in losing by death two of its oldest members. Dr. J. R. Airey, who died on 16 September, 1937, joined the Committee in 1907, and remained associated with it until his death. During this period he was indefatigable as a com- puter, and was responsible for the production, single-handed, of a vast amount of tabulating work. He was Secretary from 1920 to 1929, and served as the clearing-house for tabulation work for the British Association until the time when regular meetings in London became the recognised 270 REPORTS ON THE STATE OF SCIENCE, ETC. procedure. The Committee desires to record its appreciation of the valuable work which Dr. Airey performed as a computer, of the generosity which placed his skill and experience at the service of his friends, and of the patience with which as Secretary he conducted the affairs of the Com- mittee during the difficult period of reconstruction after the war. Prof. Alfred Lodge, who died on 1 December, 1937, attended his first meeting of the British Association in 1883. He became a Life Member in 1886 and was a member of Council from 1913 to 1915. In 1888 he joined the first Committee set up by Section A ‘ for the purpose of considering the possibility of calculating certain mathematical functions and, if necessary, of taking steps to carry out the calculations, and to publish the results in an accessible form.’ From that year Prof. Lodge was actively concerned with the tabulation work of the Association until the day of his death, and a very great deal of computation work lies to his credit, particularly in connect- ion with Bessel functions. The Committee records with gratitude its appreciation of the patient and valuable work Prof. Lodge did as a computer, of the services which he rendered to the Committee in many capacities, and of the charm of character which made him the personal friend of every member. Dr. Thompson has succeeded Prof. Lodge as Vice-Chairman. Employment of Computers.—In the last Report mention was made of the employment of a full-time computer, to work mainly on the Committee’s National Accounting Machine at the Galton Laboratory, by kind permission of Prof. Fisher. Mr. F. H. Cleaver, who was appointed to the post in January, 1937, remained fully employed under the personal direction of several members of the Committee, and under the immediate supervision of Mr. Stevens, until he resigned the post on g May, 1938. He has been succeeded by Mr. H. O. Hartley, who took up his duties on 13 June. The Committee has arranged for the demonstration of its machine at the Cambridge meeting, as part of a general demonstration of the possibilities of a number of modern calculating machines in scientific computing work. The other machines belonging to the Committee have been in continuous use, and the Committee records with gratitude the voluntary services rendered in this connection by Mr. C. E. Gwyther. A number of part- time computers have been engaged from time to time under the direction of members of the Committee, and the Committee once more gratefully acknowledges the facilities offered by the Mathematical Laboratory of the University of Liverpool for the carrying out of computation under the supervision of Dr. Miller. Bessel Functions —The Committee’s sixth volume, being the first volume devoted to Bessel functions and containing the four principal functions of orders 0 to 1, was published at the end of 1937. The volume was dedicated to Prof. Lodge, who, however, did not live to see the tables published. The work of the Bessel Function Sub-committee on the preparation of a second volume has been to some extent exploratory, and good progress has been made in the calculations. During the year the following fundamental tables have been completed in readiness for sub-tabulation where necessary : yn(x) = x" Vn(o) n =0(1)20 x =0:'0(0'1)6'0_ 14 figures. Yu(x) nm =0,1,2, x =6:o0(o'1)21‘0 15 figures. in(x) = x-"I,(x) mn =0(1)22 x =0-0(0'1)6'0_ 15 figures. log in(x) n= 20,21 x = 6:0(0'1)20°0 15 figures.. n(x) n=0(1)21 x =—o:0(0'1)6:0 _ 18 figures. log In(x) n= 20,21 x = 6:0(0'1)20°‘0 15 figures. Iy(x) n=0(1)21 x = 6:-0(o0-r)10°0 15 figures. THERMAL CONDUCTIVITIES OF ROCKS 271 The calculation of J;,(x) is being continued to x = 20. The computation of K,(x) has been performed for x = 6:0(0-1)11°5 with ro figure accuracy. The determination of the early zeros of ¥,(x) by inverse interpolation from the 12 decimal values of #,(x) already computed for x = 0-0(0°1)25°5, n = 2(1)20 is in progress. An additional term in the asymptotic series for the zeros of ¥:(x) and Y,(x) has been determined and the coefficients computed. Table of Powers ——The computation for this volume, and the preparation of copy are almost complete, but some checks have still to be applied. Airy Integral—This work, when complete, will form a part-volume of some 46 pages, including introduction. The greater part of the copy has already been prepared, and the remainder will be ready shortly. The Committee proposes to proceed as soon as possible with the separate publication of this table. Legendre Functions—Some delay has occurred in the production of these tables as a part-volume, for which authority for publication was obtained last year (see 1937 Report). The entire material has, however, been set up. Sheppard Tables—Authority has been obtained from Council for the separate publication of the tables handed to the Committee by the family of the late Dr. W. F. Sheppard, and referred to in last year’s Report. The unfinished table, alluded to last year, has been completed. All the tables have now been checked and every entry verified. Sheppard’s table of the common logarithm of the tail area of the normal curve, to 12 places of decimals at interval 0:1, has been sub-tabulated to form an 8 decimal table at interval o-o1. This small extension of the original scope of the volume is in response to a demand for a detailed table of this important function, which is much needed in statistical work. An introduction is being prepared, and the whole should be ready for press shortly. Miscellaneous.—In response to an informal suggestion, the Committee is preparing a card-index of mathematical tables to supplement existing bibliographies. This should form a very valuable source of reference for members of the Committee, and be a means of enabling them to answer outside enquiries. It should be mentioned also that the Committee has been in touch with the Tables Committee of the National Research Council of America, which is engaged under the Works Progress Administration in the calculation of certain tables of mathematical functions. Reappointment.—The Committee desires reappointment, with a grant of £200, which would be expended mainly on calculations for further volumes of Bessel functions. THERMAL CONDUCTIVITIES OF ROCKS. Report of Committee appointed to consider the direct determination of the Thermal Conductivities of Rocks in mines or borings where the tempera- ture gradient has been, or is likely to be, measured (Dr. EZER GRIFFITHS, F.R.S., Chairman; Dr. D. W. Puitutps, Secretary; Dr. E. C. Butvarp, Dr. H. Jerrreys, F.R.S., Dr. E. M. ANDERSON, Prof. W. G. FEARNSIDES, F.R.S., Prof. G. Hickiinc, F.R.S., Prof. A. HoLmgs, Dr. H. J..H. Poote). 1. Introduction —The heat flow at the surface of the earth is a measure of the heat being generated below; a knowledge of its variations from 272 REPORTS ON THE STATE OF SCIENCE, ETC. place to place is therefore of fundamental geophysical interest. To estimate this heat flow it is necessary to know the vertical temperature gradient and the thermal conductivity of the rocks in which the gradient is measured. There exist numerous measurements of temperature in deep bores in various parts of the world, but almost no conductivity data except that collected by the former British Association Committee about fifty years ago. Thus there is no trustworthy data on the variation of heat flow from place to place, though it is believed by many that considerable variations occur. In an attempt to remedy this state of affairs the Committee has pursued investigations along the following lines : (1) An attempt has been made to get the necessary data from shallow holes. This investigation has met with difficulties through dis- turbances of the temperature by percolating water. (2) Temperature measurements have been made in bores whenever they became available. (3) An apparatus has been constructed for the measurement of thermal conductivities of rock specimens. In the past it has been somewhat optimistically assumed that the con- ductivity measured in the laboratory was the proper quantity to use in the heat flow calculations. As the temperature gradient in the laboratory is of the order of 10° c./em. and that in nature 0:0003° c./km., this seems a somewhat unsafe assumption. ‘The investigations on heaters in shallow holes and on the annual temperature wave employ gradients of the order of 0°03° c./em. Comparisons of these with the laboratory determinations therefore provide a most valuable check. 2. Measurements in a Shallow Hole—If the temperature distribution is steady the flow of heat per cm? of the earth’s surface should be independent of depth. It would therefore be supposed that the heat flow could be measured as well in a shallow hole as in a deep one, so long as the hole was deep enough to get below the effect of the annual temperature wave. This would avoid the troubles associated with the use of deep bores (see § 3) and would have the added advantage that the conductivity could be measured 1m situ by the temperature distribution round buried heaters. Experiments briefly described in last year’s report showed that tempera- tures could be measured with thermocouples in a shallow hole with an adequate accuracy. A heater was installed in a 15-ft. hole in gault. When it was turned on the temperature of the thermo-junctions changed in the expected way. Examples are shown in Fig. 1. The change due to the annual temperature wave was subtracted, and expressions of the form A(1 — Erf B/t) fitted to the results. The constants A and B are functions of the conductivity, the specific heat per unit volume and of the positions of the thermo-junctions. ‘The conductivity deduced from them and from laboratory measurements of the specific heat was 0:0027. The heat flow could not be deduced from these measurements since there was a large annual temperature change even at the bottom of the hole. The results, however, were taken as indicating that the method was sufficiently promising to try in a deeper hole. A 100-ft. hole was therefore drilled at a cost of £19 in a field near the Observatory at Cambridge. Three feet of water- bearing gravel were encountered on top of the gault and the top 20 ft. of the bore was cased to exclude this water. In spite of this water continued to enter the bore from lower levels. ‘The casing was therefore continued to 60 ft., still without stopping the water; the water level was different inside and outside the casing, showing that the water was really derived from the gault and not from the surface gravel. As the hole showed signs of caving THERMAL CONDUCTIVITIES OF ROCKS 273 in, three heaters and fifteen thermo-junctions were installed as soon as the drilling was finished. As the casing was not excluding the water it was withdrawn. The presence of water in the hole makes it impossible to make satisfactory thermal conductivity measurements with buried heaters as the water content of the clay around the hole has been completely altered. As specimens of the clay had been taken every 10 ft. with precautions to prevent them being affected by the water, laboratory measurements of conductivity can be made. When attempts were made to measure temperatures with the thermo- junctions completely inconsistent results were obtained. ‘This was traced to the leads having become damp from water condensed in the tube. This dampness caused the copper and constantan wires to act as a small battery. / - O o- 21'4cem °C “ 0 7 3-0 HEATER F TURNED . ON | 1 ¢ | 2-0 | w ] ? [a4 = | = | o- 36-6.cm [- 4 5 0 2 rr] | a | O = : ii Ig 0 1-0 | ] O ; ae O O 0 L 9 O 62-3¢m eee ‘* O Z oO “ 5 6-0-5-0 | 0 2 4 6 8 10 12 14 16 18 20 22 DAYS Fic. 1.—Temperature of junctions above that of the bottom of hole. A 100-ohm copper resistance thermometer was therefore constructed in a water-tight steel case 8 mm. in diameter. Its behaviour was entirely satisfactory. ‘Temperature measurements were made in a #-in. steel pipe at every 10 ft. between the surface and the bottom of the hole (with the hole filled with water) and after it had been filled in with clay. For the lower 30 ft. of the hole the gradient was constant and equal to 33:8 + 1°5° c./km. for the filled hole and 33:2° c./km. for the unfilled hole. Between 30 and 7o ft. from the surface the mean gradient was about the same as in the lower part of the hole but the individual points deviated by up to 0-05° c. from a straight line (see Fig. 2). Above 30 ft. the annual temperature wave obscures the normal gradient. The measurements have been repeated several times and the departures from a straight line are reproducible and are certainly real. ‘They are presumably due to the circulation of water in one or more of the porous bands that are shown to exist by the entry of 274 REPORTS ON THE STATE OF SCIENCE, ETC. water into the hole during the drilling. The presence of these irregularities throws considerable doubt on the value of the gradient derived from the observations. The site for this bore hole was chosen so that the bore would be entirely in gault as this is one of the most homogeneous and least porous formations. ‘Thus if irregularities are found in the temperature curve even in this specially favourable case it is unlikely that useful measure- ments will often be possible in such shallow holes. The consistency of the measurements shows however that reliable measurements would be possible in dry holes if any can be found. Observations of temperature have been made on 10 thermo-junctions in a 15-ft. hole at intervals over a period of a year. These observations should yield an excellent value for the diffusivity of gault. Since they refer to a large mass of undisturbed clay they provide a standard for checking Fr. 40 60 xr = Qa Ww a 80 100 0-0 0-2 0-4 0-6 0-8 °C BELOW TEMPERATURE AT BOTTOM Fic, 2. laboratory measurements, for if an apparatus will measure the conductivity of gault there is little doubt that it would deal satisfactorily with more con- solidated rocks. A rough reduction of the observations suggests a value of 0:0037 cm’sec-! for the diffusivity, which combined with a specific heat of 0°39 cal/°c. grm. and a density of 2-00 gives a conductivity of 00029 cal/em.°c. sec. ‘To make a rigorous reduction involves a great deal of arithmetical labour, but it is hoped eventually to carry out the work. 3. Temperature Measurements in Bore Holes.—The Anglo-Iranian Oil Co. very kindly allowed specimens to be collected and temperatures to be measured in their bore at Kingsclere. As this bore had been made by rotary drilling with a continuous circulation of mud it was necessary to leave it for some days for the lower part to get into temperature equilibrium (see § 4). After the bore had been standing for three days an attempt was made to lower two maximum thermometers in a sealed case. It was found . to be impossible to get the thermometers more than halfway down the hole owing to an obstruction. Attempts were continued for three days without success. As this work caused great delay and inconvenience to the Anglo- THERMAL CONDUCTIVITIES OF ROCKS 275 Iranian Co. the work was then abandoned. Measurements in the higher parts of the hole would have been valueless as they had been cooled for months by the circulation of drilling mud. Similar difficulties were met with in some measurements made by the Anglo-Iranian at Portsdown. This experience shows how difficult it is to obtain satisfactory measure- ments in rotary drilled holes. Even at the bottom of the hole measure- ments cannot be taken till some days after drilling has stopped ; and, since the hole is not lined, it is very likely to become blocked during this time and can only be cleared by lowering a drilling tool for which it is necessary to circulate mud which completely upsets the temperature equilibrium again. Even if the hole should remain clear the measurements cause much expense to the company drilling the hole, since the Mines Dept. insisted that such holes should be plugged with cement at various depths and as the drilling rig cannot be removed till this has been done, it must stand idle during the temperature measurements. Measurements are therefore only possible if the hole is lined and the lining left in for some time after drilling. One such case has occurred. The Anglo-Iranian drilled a hole at Pevensey 842 ft. deep, cased it to 500 ft. and left it for some weeks. Temperature measurements were made at 765 ft. and 772 ft. (the hole was blocked below this). ‘The temperatures found at these depths were 16:2° c. and 16:3° c. There was fluid in the hole only below about 700 ft. and in any case it had not been left long enough for satisfactory measurements to be made in the upper part. The gradient has therefore to be deduced by a comparison of the temperatures at the bottom with the surface temperature. The mean air temperature at Pevensey is stated by the Meteorological Office to be 10°3° c.1_ The mean temperature of the ground a few feet down is normallyo-8° c. above that of the air.2 We therefore deduce a gradient of 5-1° c. in 668 ft. or 25° c./km. In order that it should be possible to make temperature measurements in any bores that became available two inverted maximum thermometers and a winch for lowering them on piano wire have been purchased. As the thermometers used at Kingsclere showed a great tendency to shake down on raising them from the bottom of the hole, an investigation was made of this source of error with the new thermometers. At Pevensey the two thermometers were lowered opposite ways up so that shaking would affect them in opposite directions and their positions in the container were reversed for the second run. The results agreed to less than o-1° c. As a further check a weight thermometer was constructed, but there has so far been no opportunity to use it in a bore hole. Messrs. Negretti and Zambra state that when maximum thermometers have been much used the constric- tion becomes worn and they tend to shake down more easily. The new thermometers are so difficult to shake down that it was necessary to construct a whirling case to do so. 4. Laboratory Measurements of Conductivity—In order to measure the conductivity of specimens of rock from bores an apparatus has been con- structed by Mr. Benfield of the Cambridge Department of Geodesy and Geophysics* with the advice of Dr. Ezer Griffiths. This apparatus con- sists of two brass bars one inch in diameter between the ends of which a disc-like specimen is placed. The top end of the upper brass bar is heated electrically and the bottom end of the lower is cooled by a stream of water. 1 This is deduced from the mean air temperature at Eastbourne from 1888 to 1935: 2°]. Koenigsberger and M. Miihlberg, Neues. Jahrb. f. Min., beilage bd. 31, 115, 1911. Everett, 2nd Rep. Roy. Comm. on Coal Supplies, 2, 292, 1904. 3 Mr. Benfield also made the temperature measurements in the Pevensey bore. 276 REPORTS ON THE STATE OF SCIENCE, ETC. The temperature at seven points along these bars is measured by thermo- junctions. From these the temperature drop across the specimen T and the temperature gradient p in the bars are determined. If there were no loss of heat by convection and the specimens were in perfect thermal contact with the bars, the conductivity of the specimen, k would be given by k = CpS/T where S is the thickness of the specimen and C is a constant that may be determined by measurements on a substance, such as fused silica, whose conductivity is known. The loss of heat by convection may be reduced by enclosing the apparatus in a bell-jar across which run paper discs. The remaining loss may be estimated from the departure of the temperature distribution in the bars from linearity and allowed for. The error from the lack of perfect thermal contact between the bars and the specimen may be eliminated by making measurements on specimens of two different thicknesses. For this elimination to be satisfactory it is de- sirable that the contact should be as good as possible. Experiments on the best method of joining the specimens to the bars are in progress. Painting with a thin layer of very thick cellulose varnish seems the most promising method. If the specimen is pressed on the bars while the varnish is still tacky the minute irregularities in surfaces of the specimen and the bars are filled with celluloid. The preliminary tests of the apparatus are being made with specimens from Kingsclere, when it is working satisfactorily measurements will be made on the Pevensey specimens. A specially careful investigation will be made on the Cambridge Gault for comparison with the values obtained by the methods described in § 1. (5) Theoretical Investigations—If the surface of the earth is not a plane of constant temperature there will be irregularities in heat flow that may mask those due to variations in conductivity and in the generation of heat. Dr. Jeffreys has devised a method of allowing for these ; his investigation, which has been published in Vol. 4 of the Geophysical Supplement to the Monthly Notices of the Royal Astronomical Society, shows that the dis- turbance Sv of the temperature gradient at a depth Z below the surface is given by i ae su = [e tay? dr P . (1) oO where wv is difference between the mean temperature at sea level round a horizontal circle of radius r and that at sea level under the station; that is v is the mean value of (p — p’)h where p and p’ are the temperature gradients in the earth and in the air and h is the difference between the height of the station and the mean height of the circle. From (1) expressions may be derived for the disturbance at the surface and for the mean disturbance down to any depth. Certain special cases may be evaluated analytically, for example the gradient at the bottom of a hemispherical cavity is three times that at a distance from the ~ cavity, and the gradients at the crests and troughs of a series of parallel simple harmonic ridges and valleys of height 2A and wavelength differ QUANTITATIVE ESTIMATES OF SENSORY EVENTS 277 by 47 A/A times the normal gradient. Numerical solutions for a number of actual bores have been made by Dr. Bullard and published in the Geophysical Supplement ; the biggest disturbance found is for the Simplon Tunnel, where the observed gradient requires to be increased by 14 %. Dr. Jeffreys has investigated the disturbance of the temperature gradient produced by the casing ina bore. Ifa long rod of radius a and conductivity K is introduced into a solid of conductivity k with a temperature gradient p in a direction parallel to the rod, the temperature gradient within the rod at a distance s from the end differs from p by an amount 5p given by Sp/p = 1(K — k) a®/k s° If K = rook the error is less than 1 % if a/s = 50, the effect of the casing is therefore always negligible except within a few feet of the end. Future Programme.—Owing to the difficulty of obtaining satisfactory temperature measurements in rotary drilled holes it is desirable to make the best possible use of data obtained when other systems of drilling were in vogue. A great mass of temperature data exists from bores in the U.S.A., in Persia and elsewhere, much of which has been taken with every pre- caution; efforts should therefore be made to obtain specimens of the strata passed through by these bores in order that conductivity determina- tions may be made. Requests for specimens have been sent to various organisations who might be able to assist. It is easy to obtain odd specimens from bores but difficult to get a representative selection. ‘Temperature measurements should be made whenever bores are:available. Any bore over 500 ft. deep is suitable, and any dry bore over 100 ft. is worth testing. No grant will be required for this work. QUANTITATIVE ESTIMATES OF SENSORY EVENTS. Interim Report of the Committee appointed to consider and report upon the possibility of Quantitative Estimates of Sensory Events (Prof. A. Fercuson, Chairman; Dr. C. S. Myers, F.R.S., Vice-Chairman ; Mr. R. J. Bartiert, Secretary; Dr. H. Banister, Prof. F. C. BarTLeTT, F.R.S., Dr. Wm. Brown, Dr. N. R. CampBeELt, Prof. J. Drever, Mr. J. Guitp, Dr. R. A. Housroun, Dr. J. C. Irwin, Poe Gy WC Kaye, OBE. Dr.oS. JF. Parrott, Dr. L. F. RicHarpson, F.R.S., Dr. J. H. SHaxpy, Mr. T. Smitu, F.R.S., Dr. R. H. Tuouxess, Dr. W. S. Tucker, O.B.E.). INTRODUCTION. Tuis Committee, whose title indicates its terms of reference fairly accurately, was appointed at the York meeting in 1932, and has met since at irregular intervals, much of its work having been carried out by corre- spondence between members of different views and the circulation of statements made by members. In the early stages of the Committee’s existence, it seemed impossible to reach an agreement, and it soon became obvious that it was necessary to investigate the general implications of the term measurement and of the processes involved in the making of measurements, and that it would be 278 ‘REPORTS ON THE STATE OF SCIENCE, ETC. profitable to study what was actually ‘measured’ in a number of experi- ments carried out in psycho-physical research. Further, it was evident that some of the experimental conditions under which these researches were carried out must come under review, and that considerable light would be thrown on the problem by a study of the historical order of development of the subject of mental measurement. The Committee has been fortunate in securing the services of specialists who have collected and discussed, in detail, the evidence for the different views, and feels that it can best serve the advancement of this particular branch of knowledge by putting forward the evidence for these views without at present making any attempt to reconcile them. To this end Mr. Guild has prepared a statement of the point of view of those who deny the possibility of quantitative estimates of sensory events, and Prof. Drever has dealt more briefly with the question from the opposite angle. Mr. Guild’s statement has been circulated to the Committee, and notes and criticisms received from members are included in the Report. Prof. Drever, who had waited for Mr. Guild’s paper before completing his own work, feels that a longer time is needed for a full presentation of a reply to Mr. Guild’s position, but has sent in a short statement presenting the case for those who give the affirmative answer to the question whether sensation intensity is measurable. Extensive experimental work has been carried out in the Cambridge Psychological Laboratory, and Mr. Craik has prepared a short summary of this work, to which Prof. Bartlett has added an introductory note. Dr. Semeonoff, of the University of Edinburgh, has collated and studied critically the immense literature connected with the subject of the measure- ment of sensory magnitudes, and he has been kind enough to permit the Committee to include in its Report that portion of his work which refers to the measurement of sound sensation. For consideration of the Sections the Committee therefore present the following : I. An historical statement by Dr. B. Semeonoff. II. A short summary of recent Cambridge experimental work by Prof. F. C. Bartlett, F.R.S., and Mr. K. J. W. Craik, M.A. III. A statement by Mr. J. Guild. IV. Notes thereon by: A. Dr. R.H. Thouless. B. Dr. L. F. Richardson, F.R.S. C. Mr. T. Smith, F.R.S. D. Dr. Wm. Brown. E. Dr. J. H. Shaxby. V. A statement by Professor J. Drever. I. An historical statement by Dr. Semeonoff. ‘THE MEASUREMENT OF SOUND SENSATION. Earty work on the measurement of sound sensation was closely bound up with two other studies: (i) the search for a simple method of measuring sound intensity, and (ii) the experimental verification of the validity of Weber’s law and its derivatives. Reviews of the early work on sound measurement were made in 1905 . by Titchener (57), and in 1910 by Pillsbury (43). These naturally exclude the recent work using electrical methods, the development of which has revolutionised the whole field. A brief survey of these later methods was QUANTITATIVE ESTIMATES OF SENSORY EVENTS 279 made by the present writer (49), who quotes references to fuller and more technical accounts. The pioneer researches were marred both by imperfections and in- adequacies of technique, and by theoretical misapprehensions. Of these drawbacks, those of the second type apply more particularly to methods based on the principle of falling bodies, those of the first both to these methods and to those based on the validity of the inverse square law. The principle that the intensity of a stimulus which reaches the receptor from a distant source varies inversely as the square of the distance of the source from the receptor is still sometimes used, in the form of the ‘ watch test,’ by practising aurists in the determination of hearing loss. This method, while suitable for rough estimates, is not to be recommended for accurate measurement, since reflection of sound waves is inevitable, and practically uncontrollable, even in the open air. The method of falling bodies rests on the principle that the energy of a falling body is proportional to the weight of the body, and to the height of fall. Gravity being constant, it may be said that the product of height and weight gives a measure of the energy. Since, however, not all the energy is effectively transformed into sound, the simple ht. x wt. formula does not hold, and it was found by the early experimenters that in general a fractional power of the height had to be taken in calculating sound in- tensity. These conclusions were often reached as a result of equating for loudness the sounds produced by balls of varying size and weight, and it was usually noticed that differences of quality made such observations extremely difficult. Actually apparent equality of loudness under these conditions is no criterion of equality of intensity, and it is surprising how completely this rather obvious point was overlooked. Studies of the inter-relation of sensory attributes, which for sound may be said to date from the discovery in 1897 of the Broca phenomenon (6), have now established beyond dispute the fact that no point-to-point correspondence can be claimed between the psychological qualities of sensation and their physical correlates. Following Fletcher (13), we may say that while loud- ness is the subjective characteristic that is recognised as the magnitude of the sensation, and which changes most rapidly with changes in intensity, each of the three main subjective characteristics of sound—loudness, pitch and timbre—depend on all three of the physical characteristics—intensity, frequency and overtone structure. Attempts to measure sound intensity were also made using such devices as singing flames, percussion systems with or without tuning-forks, phono- graph records, blowing pressure, and direct microscopic examination of the amplitude of vibrations. Some of these instruments were used in investigations of Weber’s law, and apart from this approach little attempt was made to measure sensation as such, i.e. to express sensation magnitudes in relative or absolute units. At the time of the 1913 symposium in the British Journal of Psychology (40), the general consensus of opinion was that theoretically sensation was not measurable, but that Weber’s law might hold, at least over a limited range, in most sense-departments. Fechner’s ‘ fundamental assumptions,’ first stated in 1860 in the Elemente (12), on which he based his mathematical development of the S (sensation) = k log R (stimulus) relation,! were taken 1 Sometimes stated S = k log R/Ro, to indicate that the stimulus is measured in terms of its absolute threshold (R,) as unit. This is the law quoted in Warren’s Dictionary of Psychology under the heading Fechner’s Law. The definition adds : “Fechner’s law is frequently incorrectly called Weber’s Law, and is now often referred to as the Weber-Fechner law.’ 280 REPORTS ON THE STATE OF SCIENCE, ETC. as the necessary conditions on which depended the measurability of sensation, so that this measurability stood or fell with the constancy of the “ Weber-Fechner fraction.’ This approach to the relation between stimulus and sensation has now been almost wholly superseded by other methods, though interest in the constancy of the difference threshold has not entirely died down. It is, of course, difficult to date this change of attitude with any degree of accuracy, but a useful turning-point may be arbitrarily fixed by the publication in 1920 of a review by Marx (35) of work on die Unterschieds- schwelle bet Schallempfindungen. Before this date work on the stimulus- sensation relation for sound was done exclusively by means of what we may term the ‘ Weber-Fechner approach,’ the value of the just noticeable difference was usually found to be fairly constant, and the sounds studied were for the most part unpitched sounds (usually described as ‘ noises ’). After 1920 developments in electrical apparatus made work with tones progressively easier and more accurate, the difference threshold was found to be much less constant than had previously been supposed, and new methods of investigation were evolved. ‘These new methods may be classified under two main heads : I. Attempts to assign numerical values to actual sensations, or to determine values of a stimulus whose subjective effect should bear a given numerical relation to the subjective effect of another value of the same stimulus; II. Attempts to discover the relationship between measurable physiological events and the physical values of the stimulus. When the former can be shown to bear the same or a similar functional relationship to the stimulus as the subjective effects noted above, the hypothesis is commonly advanced that loudness is determined by some such variable as the rate of change of the physiological process or the number of nerve units activated. These are not discussed in the present summary, since their relevance to the measura- bility of sensation depends entirely on whether one is prepared to accept as valid the hypothesis mentioned. In addition, the period under discussion has seen the development of noise-analysis methods, by which a complex sound can be reduced to a “ frequency spectrum,’ and a better understanding obtained of the apparent anomalies of masking. Table I contains a detailed summary of the principal work on Weber’s law in its application to the intensity of sound ; the following descriptive notes may be of interest as giving a better indication of the actual experi- mental procedures employed. They also contain mention of a few researches not included in the table. The material may be divided into five groups as follows: (i) the earliest work, 1856-79; (ii) work reported in a series of articles in Wundt’s Philosophische Studien, 1883-1900, and performed for the most part in Wundt’s Leipzig laboratory ; (iii) early work on tones, 1888-1905 ; (iv) later work on tones, using electrical apparatus, 1922-35 ; (v) miscellaneous work with a variety of instruments, and usually with some other end in view than a simple examination of the truth of Weber’s law, 1930-37. The succeeding sections are numbered in accordance with this classification. (i) The experiments of the first group gave inconclusive results, and are of interest chiefly for historical reasons. In particular, the work of Renz and Wolf (44) is significant in that it is ‘ pre-Fechner,’ and seems to have anticipated the standardisation of the psychological methods. Renz and Wolf, medical undergraduates at Tiibingen, experimented with a watch, intensity being measured in terms of distance. Various devices used to eliminate accidental errors showed a nice balance between the requirements ~~ 20% QUANTITATIVE ESTIMATES OF SENSORY EVENTS 281 of experimental accuracy and those of the comfort of the subject. Only one standard intensity was investigated, but both time-orders were used. The rather naive conclusion was drawn that certainty of judgment grew with increasing difference of intensities. Individual differences between the results of the two experimenters, who acted as their own subjects, also received comment. Fechner in the Elemente (12) derived his data on sound intensity from results obtained by Volkmann, who carried out two series of experiments. In the first, he used a simple improvised sound-pendulum, consisting of a strong knitting-needle as axis, and a wooden hammer which struck against a four-sided glass flask. "Two heights were found such that in the majority of cases the observer could tell which gave the stronger sound, and observa- tions were made at four distances, varying from 14 to 18 paces. It was found that judgment remained as sure and correct at all distances, and from this it was concluded that the difference threshold was independent of the absolute value of the stimulus. Experiments with freely-falling bodies gave for two subjects out of three a ratio of intensities 3:4 for which a difference could be accurately judged, while with a ratio 6 : 7 considerable uncertainty occurred. A much fuller investigation was reported by Nérr (42), who introduced a number of refinements into his falling-bodies technique. A much wider range of intensities was used, and catch-experiments were introduced, in which the standard was presented with itself. Unfortunately, the numerical results are such as to make the calculation of difference thresholds by any of the ordinary procedures practically impossible. Nérr, however, con- cluded that differential sensitivity remained constant from the weakest to the strongest sounds. (ii) Dissatisfaction with No6rr’s results seems to have been one of the contributing causes of the work of the Leipzig group. ‘This series of researches is of particular interest in that the writers had first-hand contacts with one another, even to the extent of opportunities of working with the same subjects and the same instruments. One of their main interests was the exact measurement of the sounds produced by the falling bodies, discussed above. Tischer (56) and Lorenz (31) used Hipp’s fall-apparatus. Tischer’s results show wide individual differences among his five subjects, and considerable variation over a fairly small range, together with a progressive improvement of discrimination with practice. Nevertheless, the results are described as ‘so gut wie constant.’ Lorenz, on the other hand, was aware that his results were insufficient for generalisation. He characterises the constancy obtained as fairly satisfactory, and states that it might have been better with greater care. Starke (50, 51), Merkel (36), and Mosch (39) used Wundt’s improved fall-apparatus, and introduced further experimental refinements. Mosch laid particular stress on the ‘ error’ aspect of variations in the difference threshold, and introduced further categories of judgment (‘ much greater,’ “much less’). Kampfe (23) and Ament (3) reverted to the use of the sound-pendulum, making considerable improvements on the model used by Volkmann. Ament’s work shows increased recognition of individual differences, and also a decided drop in the value of the difference threshold after the weaker intensities had been passed. In both these respects Ament anticipates the results of later experiments. A slightly different approach to the stimulus-sensation problem is seen in the work of Merkel (37) and Angell (5). Merkel and Angell used the method of ‘ Mean Gradation ’ to find an estimated mid-point between two 282 REPORTS ON THE STATE OF SCIENCE, ETC. TABLE I Date. Authors. 'I 2 B 4 5 6 1856 | Renz and Wolf(44) | W fo) Palen -38 1860 | Volkmann (12) . P 22 C? Rk 1860 - . | FA | wide ? 33 1879 | Norr (42) . .| FA 55 Lad) ee k? 1883 | Tischer (56) aie ys 30 Pel eri; “4 indiv. diffs. 1885 | Lorenz (31) Fol ind DIAN EL 8 VAX) ripe hel 79 Gaile 5) upper dev. 1886 | Starke (50,51) . | FA 10 Zeal ele, 13 1888 | Wien (59) . Pe ek entero L, C| -12,:2} dev. at both ends. 1888 | Merkel (36) . | FA | 40 L 3 1893 | Kampfe (23) d Pi swale snes. pie k 1900 | Ament (3) . ; P 5 in lenle, 3 lower dev. ; indiv. diffs. 1904 | Hoefer (22) . | FA | small C | notk | irreg. var. 1905 | Deenik (11) Seal Pl Pipl i23 L Zag 1905 ae (OP L | -1--2| irreg. var. 1907 | Keller (24) . | FA | small} 9 | *, L I 1922 | Guernsey (19) . | VO 6} L 3 lower dev. 1922 | Knudsen (29) . | VO/| wide/} 4] L i lower dev. 1924 | Halverson (20) . | VO | 23 xi, 1C 2 lower dev 1928 | Riesz (46) . . | VO | 100 12 | L | -1--3] lower dev.;reg. var. 1929 | Kellogg (25) . | AO 5 ? 1? 1929 55 (26) . | AO | wide? C *12 | irreg. var.? 1930 | Macdonald and Allens (32,2) =x) | Vi 10 L | not & | reg. var. 1930 | Kenneth and Thouless (27) VO | wide| 2] L ar lower dey.; reg. var. 1934| Churcher, King and Davies (10) | VO 80 4| C | notk | reg. var. 1935 | Gage (16) . ae peVO) 24 L | not Rk | lower dev. ; reg. var. 1935 | Telford and Denk | VO | 20 | 12| L | notk | lower dev. ; (55) reg. var. 1935 | Montgomery (38) | VO 70 4| C |notk | reg. var. 1936 | Semeonoff (49) . | W 12 4 | L | not Rk} irreg. var. 1936 33 . | FA I 3 C "2? 1936 A ied Be Se 80 4 | L | not k| reg. var. 1937 Upton and Holway| VO 28 I not k function of (58) time. Notes to columns : : I. Sources: W, watch; P, sound-pendulum; FA, fall-apparatus; TF, tuning-fork(s) ; OP, organ-pipes; VO, vacuum-tube oscillator; AO, audio- oscillator ; V, variator. 2. Approximate range in db. 3. No. of subjects (when stated). 4. Methods: C, Constant method, or some variety thereof: L, method of - Limits; *, see text. 5. Modal value of threshold; when constant (). 6. Deviations from a constant value at low or high intensities ; course of the threshold over range studied, etc. QUANTITATIVE ESTIMATES OF SENSORY EVENTS 283 ‘terminal stimuli.’ Merkel’s results suggested that this mid-point lay nearer the arithmetic than the geometric mean of the terminal values, while Angell found the opposite to be true. Angell’s result is in accordance with the requirements of Weber’s law and Fechner’s derivatives ; Merkel’s, on the other hand, would seem to support Plateau’s ‘ quotient-hypothesis ’ described by Brown and Thomson (7) as the ‘ one-time chief rival of the Weber-Fechner law.’ This theory postulated direct proportionality between the just noticeable difference of sensation and that of stimulus, and at one time had many supporters, though later Plateau himself repudiated it. The Merkel-Angell controversy attracted a good deal of attention, e.g., from Ament (3), who showed that the values of the mid-stimulus were a function of both the ratio between and the absolute values of the terminal stimuli. The work of the Leipzig group was summed up by Wundt himself (60), who believed that hearing was the sense-department in which Weber’s law was of the widest application. At the same time he admitted that the method of mean gradation seemed to yield mean values closer to the arithmetic than to the geometric mean. Though not strictly belonging to the same group, the work of Hoefer (22) and Keller (24) may conveniently be included in the present section. Hoefer studied auditory differential sensitivity among individuals suffering from psychoses and functional neuroses. Subnormal sensitivity was found only in a few cases, though flagging of attention was often evident. Keller, using a modification of Mosch’s method, found that Weber’s law held good, with a mean value of about ;},, as against the figure of } usually found by previous investigators. Keller also believed that the Gaussian law of error did not hold in psycho-physical experiments, so that methods involving its application were to be avoided. (iii) All the work discussed so far was concerned with unpitched sounds. Wien (59) was the first, by nearly twenty years, to work with tones. These were produced by electrically-driven tuning-forks of three frequencies, and the intensity range was much the greatest of any in the early researches. A resonator, covered with the membrane of an aneroid barometer, served as an artificial ear-drum, by means of which the relative amplitudes of vibrations could be measured with great accuracy. Wien’s work is remark- able not only in respect of its pioneer use of tones, but also in that on the basis of his results he drew up an empirical equation for the difference threshold, which, in its integrated form, gave a curve for the relation between stimulus and sensation surprisingly similar to that recently adopted as a standard by the American Standards Association (4). Deenik (11) extended Wien’s frequency range, and experimented with organ-pipes as well as with electrically-driven tuning-forks. In the case of the former the subject himself adjusted the intensity of the variable until a difference was noticeable. Unfortunately Deenik’s intensities were not so conveniently graded as Wien’s, and in general his interest was con- centrated rather on differences of sensitivity as a function of frequency. It is worth mentioning, however, that Deenik found that the finest thresholds were in the region of 2,000 cycles; this corresponds quite well with the point at which recent work has shown that the widest range exists between the upper and lower thresholds of hearing. (iv) The present section marks the beginning of work with vacuum-tube oscillators. Unless otherwise stated, it is to be assumed in sections (iv) and (v) that some form of oscillator was used in all the studies reported. Like Deenik, Guernsey (19) was chiefly interested in the variation of the intensity threshold with pitch. Her point of maximum sensitivity, how- 284 REPORTS ON THE STATE OF SCIENCE, ETC. ever, was located somewhat higher—between 3,000 and 7,000 cycles, results varying for different observers. Mackenzie (33) made use of a principle similar to that of optical flicker. Mackenzie found that if two frequencies alternated in the ear at a fairly rapid rate, the interruptions of the louder were more conspicuous than those of the weaker. It was possible to adjust the intensities until the two tones appeared equally interrupted ; at this point the respective loudnesses were taken as equal. A comparison of the physical values of the tones thus balanced showed that except at weak intensities, where room-noise was held to have an interfering effect, the relative sensitivity of the ear was invariable over the whole hearing range. Knudsen (29) also used an alternation method, whereby two intensities of the same tone were alternated at the rate of about fifty changes per minute, the difference between them being decreased or increased until the ‘ flutter * ceased or began to be apparent. ‘The value of the difference threshold was shown to decrease continuously with rise in intensity, until a constant value was reached. ‘The point at which the curve flattened in this way was shown to vary for different frequencies, but on the whole the value of the threshold seemed to be independent of frequency. Knudsen also drew up a generalised equation intended to serve as a truer expression of differential sensitivity, and showed that computed values of the threshold based on this formula agreed fairly well with his experimental results. Knudsen’s results share with those of Riesz (46) the distinction of having been used by subsequent investigators as the basis of theoretical considera- tions and calculations. Riesz measured differential intensity sensitivity by determining for a tone of given frequency and intensity the minimal intensity to which a second tone, differing from the first by 3 cycles per second, had to be raised to make the beats just perceptible. ‘Twelve observers each worked with seven tones ranging from 35 to 10,000 cycles; the whole range of intensities, from the absolute threshold to near the threshold of feeling, was covered. ‘The general conclusion as regards Weber’s law was that it held at all frequencies for intensities above 10° times the absolute threshold value. Curves showing the difference threshold plotted against a logarithmic intensity scale seem to confirm this, unless the threshold axis is itself logarithmic, in which case the curves do not seem to flatten per- ceptibly at any point of the intensity scale. ‘This observation, however, is based on replotting some of the data of smoothed curves, and as such is no doubt open to question. 7 Telford and Denk (55) confirmed Riesz’s results rather closely for one frequency (800 cycles). The form of the curve obtained was almost identical with those of Riesz, but the apparatus used was such as to make measurement of intensities in terms of db level impossible. Further, for some reason not very apparent, thresholds were calculated from the formula (I,2 — I,?)/I2, where I, and I, were the lower and higher intensities respectively. (v) The work of Macdonald and Allen (32, 2) shows a departure from recent practice in that the sounds studied were variator tones, of which the intensities were measured in terms of blowing pressure. The authors follow Merkel and others in their recommendation that the reciprocal of the threshold be used as a measure of sensitivity, so that a higher numerical value would indicate heightened sensitivity. The main finding was that Weber’s law did not hold, since a plot of the reciprocal of the threshold, against intensity fell into two distinct parts. A new empirical equation was suggested as holding good (with appropriate changes of constants) for hearing not only under normal conditions, but also under conditions of QUANTITATIVE ESTIMATES OF SENSORY EVENTS 285 depressed and enhanced sensitivity, obtained by previously stimulating the ear to be tested, or the other, with tones of the same frequency as the test tone and about 15 to 20 times its intensity. Gage (16) investigated the variation of the uniaural difference threshold with simultaneous stimulation of the other ear by tones of the same fre- quency. Gage’s detailed results are not relevant to the present purpose, but his general results suggest the occurrence of high values of the threshold at low intensities to a very marked degree. An unusual approach to the continuity of the value of the difference threshold is seen in the work of Kenneth and Thouless (27), who claimed to show that this continuity extended to the absolute threshold. By start- ing at zero intensity and taking several intermediate values of the stimulus between this and the absolute threshold of hearing, they demonstrated that the just noticeable difference varied continuously until a point was reached at which it so happened that the requirements of Weber’s law were fulfilled over a certain range. The work of Churcher, King and Davies (10) is interesting (a) for its stress on the continuity of variation of the difference threshold, and (b) for the fact that the just noticeable increments and decrements of intensity found were not such as would occur if Weber’s law held good. This suggests the importance of ‘set,’ a point more fully dealt with by Montgomery (38, see below). Differential sensitivity to cyclical changes of intensity was also studied, though the discrepancy noted under (b) above made this method, in the authors’ opinion, not strictly valid. If this objection is a real one, it would seem to apply also to all the ‘ alternation ’ methods used in other investigations. In addition to a direct investigation of differential sensitivity at four intensity levels, Montgomery (38) made a systematic survey of the effect of ‘ set’ as determined by variations in experimental conditions. ‘Table II shows thresholds, expressed in both db and fractional form, for the thermal noise from a high-gain amplifier at an intensity level of 40 db. These figures stress the difficulty, noted also in connection with loudness estima- tion, of comparing results obtained by different experimenters using different methods. TaBie II. (Montgomery.) Threshold Method. db AR/R Switch not controlled by subject; 1 comparison ; 4-sec. between tones ; 0:8 0:20 Same, but no interval between tones 0°6 orl5s Repeated comparisons ; no interval 0'4 0096 As above, but switch controlled by subject o°2 0*047 Sinusoidal (cyclical) variation : o's oun A further point was made by Upton and Holway (58), whose chief interest was to demonstrate that differential sensitivity to sound intensity was a specific reproducible function of exposure-time. Interpreted from the point of view of Weber’s law, the results indicate that while relative constancy of the threshold was obtained with long exposure-times, with 286 REPORTS ON THE STATE OF SCIENCE, ETC. times less than 10 seconds considerable fluctuations (of an irregular character) were found within the range represented. The present writer (49) carried out short series of experiments with various instruments. (a) Since watch-tick experiments had apparently not been performed since the time of Renz and Wolf, it was decided to see what improvements could be made on their procedure. Four in- tensities were studied, upper and lower binaural thresholds being obtained for each of four subjects. A stop-watch which could be operated noise- lessly was used. Marked individual differences were found, and.only a very crude approximation to constancy over a limited range. (b) Three subjects participated in some experiments with Wundt’s fall-phonometer ; a lower threshold was found for two heights, using both time-orders. Individual differences were again noted, but an overall average of about o:2 seemed to be indicated, this value falling between those obtained by the Leipzig group on the one hand, and Keller (24) on the other. (c) Lower thresholds for four subjects were found by the method of Limits, using a valve-maintained tuning-fork (frequency 512 cycles), devised by K. J. W. Craik. ‘The sound was suitably amplified, and heard in a moving-coil loudspeaker. The following are some of the conclusions reached : (1) Weber’s law did not hold, even for a limited stimulus-range ; the value of the threshold increased at both extremes, and varied continuously throughout ; (2) Individual differences with respect both to fineness of discrimination and to shape of curve were found; (3) Although curves for each subject remained fairly constant in shape, marked day-to-day variations in sensitivity seemed to occur. The psycho-physical method commonly known as ‘ Mean Gradation ’ acts as a convenient link between the Weber’s law investigations and the recent work on the construction of sensation scales, since it can conveniently be used in either connection. The present writer carried out a series of experiments with this method, the purpose being to repeat, with variations, the work of Merkel and Angell. The instrument used was the tuning-fork described above. The stimulus ratios were 1:10 and 1 : 1oo—rather higher than those studied by Merkel and Angell. Each ratio was judged by two subjects at three intensity levels, spaced at intervals of 20 db. Some difficulty was experienced in finding a criterion of ‘nearness’ to either mean, but taken all over, the results seemed to favour a closer correspon- dence of the estimated with the geometric mean. More systematic work using the same method was carried out by Gage (17), who was interested in the following problem: If a mid-stimulus value X, be found between extremes X, and X;, and further mid-values X, and X, be then found between X, and X, and X, and X;, then a mid- value X,’ between X, and X, should, if a sensation scale is to mean anything, coincide with X,;. (This would hold irrespective of whether the mid-values coincided with the geometric or the arithmetic mean.) Gage found that the required correspondence did not occur, discrepancies of 5 and 6 db being obtained over a range of 40 db. Newman, Volkmann and Stevens (41), on the other hand, repeated Gage’s work, introducing certain refine- ments in the procedure, and reduced the discrepancies between X 3 and X,/ to 0-18 to 0:36 db over a range of 20 db, which actually, in terms of loudness values, was a greater interval than Gage’s. ‘The authors therefore concluded that the method of ‘ bisection’ (as it is now generally called) could after all be used as the basis of a loudness scale. f Other work on loudness scales has been done by a variety of methods, which, grouped together, may be said to constitute the most satisfactory and satisfying approach to the stimulus-sensation relationship. In the QUANTITATIVE ESTIMATES OF SENSORY EVENTS 287 following paragraphs the work is discussed in chronological order, but a classification may be attempted as follows : (a) The observer matches for loudness sounds of different frequencies or frequency spectra, and the results are compared with those of physical measurement methods. (6) The observer selects from a given range a sound which he believes to bear a given numerical relation to a standard sound. (c) The observer estimates in numerical terms the ‘ loudness-value’ of a given sound, as compared with a standard sound to which the value unity is assigned. The pioneer work, apart from that of Wien (59), was that of Sabine (48), who performed an experiment in which organ notes of different frequencies at octave intervals were balanced for loudness. ‘The results, described as “surprisingly concordant,’ can be expressed in the form of a ‘ loudness contour,’ which, except for a sharp drop at the two upper frequencies, is not unlike those of Fletcher and Munson (14, see below). Fletcher and Steinberg (15, 52), investigating the estimation of overall loudness of a complex sound, showed that a total loudness could be obtained by summing a fractional power of the weighted energy of each frequency region. Calculated and observed values were found to be in good agree- ment, and a rather complicated empirical equation determined. This formula has not found universal acceptance. Kingsbury (28) made a direct comparison of the loudness of eleven pure tones within a frequency range of 60 to 4,000 cycles, with a 700-cycle tone as reference. A series of curves relating sensation-level and loudness has been much quoted by subsequent investigators. Richardson and Ross (45) were the first to use what have sometimes been called ‘ intuited’’ loudness units. A tone of pleasant loudness was chosen as standard, and assigned the value 1:00. This (8S) was presented along with variables (V) in the form SVSV, and the observer wrote down his estimates of the numerical value of the variable. Of the eleven observers, all were able to perform the task with some measure of success, although many found it difficult, or complained that they were only guessing. Different forms of relation were obtained for different subjects, but in no case was it found that the estimates conformed to the formula S = k log R. Marvin (34) applied the loudness-balance method to the measurement - of ‘noises’ of various kinds, these being matched against a 1,000-cycle reference tone. It is not quite clear whether Marvin was testing aural balancing or the meter which he used, but good agreement between the two was obtained. Laird, Taylor and Wille (30) were the first to study ‘ fractional’ and ‘multiple’ loudness. An audiometer buzz was presented along with another of lower intensity, and the observer was asked to say whether the latter was half the previous loudness, or whether it had to be raised or lowered to give half the loudness of the original. The same procedure was carried out for reductions of one-fourth and three-fourths. ‘The estimates of half loudness were checked by ‘ doubling,’ i.e. asking for a loudness judged to be twice that of a standard. Curves drawn on the basis of the results show a fair degree of consistency, and the authors drew up a ‘ tentative law’ to express the results. No marked individual differences were revealed. Ham and Parkinson (21) carried out experiments similar to those both of Richardson and Ross, and of Laird, Taylor and Wille. In the first 288 REPORTS ON THE STATE OF SCIENCE, ETC. group the observer was asked what percentage of an original (i.e. reference) loudness was ‘ left in’ a comparison loudness. In the second, the observer was required to select from a range of seven or eight variables a value which appeared nearest to a given fraction (4, +, +) or a given multiple (2, 3, 5) of the standard. The stimuli used consisted of warble tones, single frequency tones, and room noise recordings, all reproduced on special records. The frequencies covered were 250 to 2,500 cycles, and the intensity levels varied from 34 to 84 db. Plotting multiple increase of original loudness or re- ciprocal of remaining fraction of original loudness (y) against energy change in db, it was found that an equation of the form y =a + be” gave the best fit to the data. The best results were obtained with the second of the methods noted. In all, 175 subjects were tested. Each individual’s judgments were consistent over a wide range, though they might differ from those of other observers. The authors proposed a noise measurement scale on the basis of their results—a straight line relation between multiple loudness units on a logarithmic scale and db above threshold. Geiger and Firestone (18) worked on rather similar lines to those of the researches just described. In this experiment the observer himself set the variable loudness to a value bearing the required relation to the standard. The fractions required were }, +, 45,745; the multiples were 2, 4, 10, 100. Tones of 60 and 1,000 cycles, and a complex noise of over forty components were studied at three intensity levels: 30, 35, and 80 db. Results similar in some respects to those of Kingsbury (28), and showing a good degree of self-consistency were obtained ; on the other hand, they seemed to be at variance with those of more recent experimenters. The general conclusion was that loudness judgments are made on the basis of actual sensation. Riesz (47) advanced the hypothesis that two tones of different frequencies would sound equally loud when their intensities were such that the ratios of the number of distinguishable steps above the absolute threshold to the number of such steps above the threshold for a reference tone of the same frequency were the same for both tones. ‘This was put to the test using as reference one of Munson’s equal loudness contours, and a good corre- spondence between observed and theoretical values was obtained, except at the two highest intensities, at which the influence of the threshold of feeling was probably operative. The most authoritative work to date on the measurement of loudness is that of Fletcher and Munson (14), whose results have been adopted by the American Standards Association (4). The intensity levels at which pure tones of frequencies from 62 to 16,000 cycles sound equally loud was determined by comparison with a 1,000-cycle reference tone. Both ears of eleven observers were tested, at all intensities. The results are sum- marised in two sets of curves. The first set shows equal loudness contours relating frequency to sensation level (i.e. db:above the threshold for that frequency). ‘The second shows a similar set of contours, but with intensity levels (i.e. db above a uniform reference level) as ordinates. The greater part of the authors’ paper is devoted to the calculation of the loudness level of a steady complex tone; the empirical formula derived is of rather a complicated character. A new loudness scale designed for free-space listening, was devised BY Churcher, King and Davies (9). To begin with, a scale based on a number of just perceptible increments above the absolute threshold of an 800-cycle QUANTITATIVE ESTIMATES OF SENSORY EVENTS 289 reference tone was constructed. This relation was found to be more satisfactory than simply adopting the decibel scale as a loudness scale, but it still conflicted with introspectional evidence as regards loudness. A method whereby observers adjusted tones to half an original loudness was therefore substituted; the procedure was progressively repeated six times, and estimates of quarter loudness gave a fairly good check ; thirty-four subjects took part. The authors go on to describe the applica- tion of their scale to the assessment of total noise by an aural balance method. This was held to give better estimates of loudness than methods of frequency analysis, the use of which, it was said, might give discrepancies of anything up to 40 per cent. when compared with direct noise-meter readings. At the discussion following the original reading of the paper just discussed, various numerical relations approximating to the authors’ scale were pro- posed. A friend of the present writer, however, has suggested an ex- ponential equation: JZ (loudness) = 100 e°°5*-5 (where x stands for sensation level in db); this, though not accurate, especially at the lower end, corresponds as well as any of the other suggested formule, and is more in line with the results of Ham and Parkinson, and of the present writer (49), who experimented on loudness estimation with the tuning-fork apparatus already referred to in two places. The procedure most closely resembled that of Richardson and Ross. Estimates of fractional and multiple loudness were made separately. For the former the unit intensities were — 30 and — 20 db attenuation on the instrument; for the latter — 30 and —4o db. Three subjects took part, and while considerable fluctuations were seen in the results of all three, those of each individual always showed more resemblance to his other estimates than to those of the others. Accordingly it was possible and necessary to draw distinct smoothed curves for each observer, so that real individual differences seemed to have been established. A full mathematical analysis of the curves was not attempted, but it was apparent that some at least were of exponential form. Checks by the ‘ (b)’ method (see p. 286) gave rather mconclusive results. One further point, however, is of greater interest, namely, that fractional estimation or judgment did not seem to give curves of the same form as multiple estimation. This may have been due to the limited number of estimations made, but it bears out the remarks on the non- comparability of results of different methods stressed by Riesz (47), Abbott (1), and others. The fullest single study of the effects of subjective condi- tions on loudness judgments is that of Steinberg and Munson (53), whose general conclusion was that ‘ when sounds of different tonal character are compared by small groups of observers, we must expect appreciable differences of judgment to occur.’ Stevens (54) states the same point in still more general terms when he says that ‘ we do not measure the magnitude of a sensation, but only of a particular dimension or aspect of sensation within a single sensory modality.’ Any auditory attribute is a function of both dimensions of the stimulus (frequency and intensity), and ‘ loudness is a name which we give to a class of discriminatory responses on the part of an organism under certain conditions of “set” and stimulation.’ Stevens goes on to propose a new unit of loudness, the sone—the loudness of a 1,000-cycle tone listened to with both ears at an intensity level of 40 db. This corresponds closely to Churcher’s (8) value 1, and is also said to be of the order of magnitude of just noticeable differences of moderately intense tones of the musical scale. The sone has not as yet been at all widely accepted, but it must be recognised as the first real unit of psychological magnitude. The phon L 290 REPORTS ON THE STATE OF SCIENCE, ETC. (B.S.)2 is defined as a unit of equivalent loudness, a sound being said to have a loudness of 2 phons when it is judged to be equally loud with a 1,000- cycle reference tone at a level of n db above a reference pressure level of 0:0002 dynes per sq. cm. Thus, on the basis of phon values one can arrange sounds in order of loudness, but it does not follow that a sound of mn phons is m times as loud as one of m phons. On the other hand, loudness values expressed in sones will presumably be true numerical magnitudes which will conform to mathematical requirements such as that just stated. Stevens also formulates an equation relating loudness to a power of the number of just noticeable differences above threshold, and derives a method of determining the subjective magnitude of a difference threshold. The claims of the various loudness scales described above, and those of certain ‘ physical’ scales, were examined by Abbott (1), who concluded that both were necessary, for different purposes. That of Fletcher and Munson was recommended for psychological purposes, as using the best available data for high and low levels, for which accurate information is often more important than at intermediate levels. BIBLIOGRAPHY. zr. Apsortt, E. J.: J. Acous. Soc. Amer., 6, 137-49 (1935). 2. ALLEN, J. F.: Philos. Mag., VII, 9, 834-42 (1930). 3. AMENT, W.: Philos. Stud., 16, 135-96 (1900). 4. AMERICAN STANDARDS ASSOCIATION, Z.24.2—1936. J. Acous. Soc. Amer., 8, 143-6 (1936). 5. ANGELL, I.: Philos. Stud., 7, 302-26 (1892). 6. Broca, A.: C. R. Acad. Sci., 124, 1512-5 (1897). 7. Brown, W., and Tuomson, G. H.: Essentials of Mental Measurement (1924). 8. CHURCHER, B. G.: J. Acous. Soc. Amer., 6, 216-26 (1935). 9. —— Kinz, A. J., and Davies, H.: J. Inst. Elect. Engnrs., 15, 401-46 (1934). IO. Philos. Mag. VII, 18, 927-39 (1934). 11. (DEENIK, A.), ZWAARDEMAKER, H.: Pyoc. Konink. Akad. Wetensch., 8, 421-6 (1905). 12. FECHNER, G. T.: Elemente der Psychophysik (1860). 13. FLETCHER, H.: J. Acous. Soc. Amer., 6, 59-69 (1934). and Munson, W. A.: J. Acous. Amer., 5, 82-108 (1933). and STEINBERG, J. C.: Phys. Rev., 24, 306-17 (1924). 16. Gace, F. H.: Brit. J. Psychol., 25, 458-64 (1935). Proc. Roy. Soc., B.116, 103-22 (1935). 18. GricER, P. H., and FirEsTongE, F. A.: Elect. Engineering, 52, 809-13 (1933). 19. GuERNSEY, M.: Amer. J. Psychol., 33, 554-69 (1922). 20. Hatverson, H. M.: Amer. J. Psychol., 33, 526-34 (1922). 21. Ham, L. B., and Parkinson, J. B.: J. Acous. Soc. Amer., 3, 511-34 (1932). 22. Horerer, G. A.: Zschr. f. Psychol., 36, 209-93 (1904). 23. KAmpFE, B.: Philos. Stud., 8, 511-59 (1893). 24. KELLER, H.: Psychol. Stud., 3, 49-89 (1907). 25. KELLocG, W.N.: J. Exper. Psychol., 12, 240-8 (1929). Arch. Psychol., 106 (1929). 27. KENNETH, J. H., and THoutess, R.H.: Amer. J. Psychol., 42, 389-98 (1931). 28. KinesBury, B. A.: Phys. Rev., 29, 588-600 (1927): 29. KNUDSEN, V. O.: Phys. Rev., 21, 84-102 (4923). 30. Larrp, D. A., Taytor, E., and Wirtz, H. H., jun.: J. Acous. Soc. Amer., 3, 393-401 (1932). 31. Lorenz, G.: Philos. Stud., 2, 394-474 (1885). 32. Macpona_p, P. A., and ALLEN, J. F.: Philos. Mag., 9, VII, 827-34 (1930). 2 Ie. British Standard, as stated in Publication No. 661—1936 of the British Standards Institution. The qualification is necessary since the term phon has already been used in Germany in the same sense, but with different defining conditions. QUANTITATIVE ESTIMATES OF SENSORY EVENTS 291 33. MackenziE, D.: Phys. Rev., 20, 331-48 (1922). 34. Marvin, H. B.: J. Acous. Soc. Amer., 3, 388-92 (1932). 35. Marx, H.: Int. Zntblatt, f. Ohrhk. u. Rhino-Lar., 18, 49-60; 113-26; 185-96 (1920). 36. MERKEL, J.: Philos. Stud., 4, 117-60 ; 251-91 (1888). Philos. Stud., 5, 449-557 (1889). 38. Montcomery, H.C.: J. Acous. Soc. Amer., 7, 39-43 (1935). 39. Moscu, E.: Philos. Stud., 14, 491-549 (1898). 40. Myers, C. S., Hicks, G. D., Wart, H. J., Brown, W.: Brit. J. Psychol., 6, 137-89 (1913). 41. NEwMan, E. B., VOLKMANN, J., and STEVENS, S.S.: Amer. J. Psychol., 49, 134-7 (1937): 42. Norr, C.: Zschr. f. Biol., 15, 297-318 (1879). 43. Pittspury, W. B.: Psychol. Monog., 13, No. I, 5-20 (1910). 44. Renz, T., and Wo tr, A.: Ann. dey Physik., 98, 596-604 (1856). 45. RicHarpson, L. F., and Ross, J. S.: J. General Psychol., 3, 288-306 (1930). 46. Riesz, R. R.: Phys. Rev., 31, 867-75 (1928). 4 J. Acous. Soc. Amer., 4, 211-6 (1933). 48. SABINE, W. C.: Collected Papers on Acoustics, 129-30 (1910). 49. SEMEONOFF, B.: Thesis lodged with the University of Edinburgh (1936). 50. STARKE, P.: Philos. Stud., 3, 264-304 (1886). Philos. Stud., 5, 157-69 (1889). 52. STEINBERG, J. C.: Phys. Rev., 26, 507-23 (1925). and Munson, W. A.: J. Acous. Soc. Amer., 8, 71-80 (1936). 54. STEVENS, S.S.: Psychol. Rev., 43, 405-16 (1936). 55. TELFORD, C. W., and DENK, W. E.: J. Exper. Psychol., 18, 106-12 (1935). 56. TiscHER, E.: Philos. Stud., 1, 495-542 (1883). 57. TITCHENER, E. B.: ‘ Experimental Psychology: a manual of laboratory practice ’ (1905). 58. Upton, M., and Hotway, A. H.: Proc. Nat. Acad. Sci. Wash., 23, 29-34 (1937): 59. Wwisy? M.: Ann. dey Physik., N.F. 36, 834-57 (1889). 60. Wunpt, W.: ‘Grundziige der physiologische Psychologie.’ 5e aufl. (1902). II. Short summary of recent Cambridge experimental work. INTRODUCTION BY Pror. F. C. BARTLETT, F.R.S. The following is a brief memorandum written by Mr. Craik on work relevant to problems of sensory measurement done mainly in the Psycho- logical Laboratory, Cambridge, during the last few years. Nearly all the methods involved rest on a use of the principle, or method, of just percept- ible differences. They are consequently subject to whatever assumptions as to measurability may be involved in that method. A considerable amount of work on supraliminal differences has also been carried out, but the difficulties encountered have not been satisfactorily surmounted, and in consequence this work is not dealt with in the present report. The general upshot of the whole of the work has been to show as clearly and definitely as possible that all the formule which have ever been pro- posed correlating physical measurements of intensity of stimuli with just perceptible difference series are valid only within wide limits. Some of the limits have now been thoroughly studied : these are, (a) rate of application of the stimulus ; (b) degree of practice of the subject ; (c) knowledge by the subject of the accuracy or inaccuracy of his reactions ; (d) state of adaptation (i) of the peripheral organs, (ii) of the central nervous system mechanism concerned. 292 REPORTS ON THE STATE OF SCIENCE, ETC. The experiments also show, though at present less thoroughly, where and how inhibitions, in the strict and proper sense, are likely to be set up, and how they can be dispelled and lead to sudden anomalous results. It still looks as if, given control of all of the determinants indicated above, and very likely of some others which we have not yet investigated in detail, human judgments, or perceptions, of equality or of difference in the case of sensory reactions set up by stimuli of constant physical magnitude do remain remarkably constant also. But it is certain that these constancies of reaction cannot be stated in terms of general laws which refer only to the physical magnitudes compared. Given, for instance, differential adaptation between the two eyes, it is the case that two simultaneously presented visual fields, one of which is 500 times as intense as the other—in terms of physical magnitude—may regularly and constantly be equated. But that amount of physical difference of intensities will, under other circumstances, produce reactions which vary widely from one another. It seems as if, provided the leading groups of physiological and psychological determining conditions are stabilised, human sensory reactions can be equated and differentiated (at least so far as liminal differences are concerned) with a high degree of constancy, and further that under these conditions the equations and differentiations remain relatively remarkably constant for constant values of physical magnitude. We conclude that probably within the human sensory reaction itself there is, or there are, some quality or qualities which enable remarkably consistent comparisons to be made in terms of equality and liminal difference. But what that quality is or those qualities are we cannot at present say. Factors AFFECTING SENSORY 'THRESHOLDS. By Mr. K. #. W. Craik. A considerable amount of work has been done in Cambridge, during the last four years, on the influence of various factors on the absolute and differential thresholds of the visual, auditory and tactile senses. It has had two purposes—the discovery of the various conditions which must be controlled, in perceptual experiments, in order that reliable results may be obtained, and the investigation of the mechanism of sensory processes, by finding the variables on which they depend. These factors are of various kinds. First, there are such as the subject’s state of health, the amount of sleep he has had, the criteria used, the number of readings taken, and the amount of practice allowed. These may be considered as extrinsic and non-specific influences, though they introduce possible sources of error and misinterpretation, if insufficiently controlled. Secondly, there are factors such as inhibition, the organisation or gestalt of the field presented, mutual interaction between two similar or dissimilar sense organs, time error, incentives, and knowledge of results, which presumably originate centrally or at some high level. In some cases these have been investigated on their own account,.in the hope that their mode of operation might be discovered ; in other cases, they have been kept constant, so far as possible, in order that the elementary responses of the sense organs to simple forms of stimulation might be studied. Thirdly, there are factors which affect either the stimulus presented or the sensitivity of the action of the sense organ itself. The spatial accom-. paniments and temporal precursors of the stimulus, and its rate of applica- tion, fall under this category ; they may have direct influence on the stimulus, or on the state of adaptation, and therefore on the sensitivity, of the sense QUANTITATIVE ESTIMATES OF SENSORY EVENTS 293 organ. It is important to be familiar with these influences, so as to avoid erroneous or anomalous results in sensory experiments ; they also supply many interesting ways of observing the behaviour of the senses in unusual situations or under slightly abnormal conditions. It is principally the last two classes of factors which have been studied in Cambridge; the results, and their theoretical implications, will be briefly summarised, and reference will be made to some of the relevant work done elsewhere. Rawdon-Smith (1934, 1) found that the absolute threshold for a pure tone of 1,000 cycles might be raised as much as 30 db. by exposing the ear for some minutes to a similar tone at 100 db. above threshold. A similar rise, though less marked, was found in the ear which had not been stimulated; this could not be explained as direct fatigue by bone conducted or air conducted sound, and appeared therefore to be due to central inhibition. The rise of threshold in the stimulated ear was apparently in great part central, since it could be ‘ disinhibited ’ by unexpectedly turning off the light in the room where the subject was seated. A considerable degree of variability and irregularity in the rise of threshold also suggested its central nature, as did the absence of any known peripheral mechanism which could produce so marked an effect. (The tensor tympani and stapedius muscles were shown in the cat to produce a fall of responses not exceeding 6 db. (Rawdon-Smith and Hallpike, 1934, 1).) Here, then, there appeared to be two central processes which could affect the auditory threshold— inhibition following exposure to a loud tone, and disinhibition by changing the stimulation of a different sense organ, the eye. A similar rise of the differential threshold, using a loud ‘ adapting’ tone and a much softer testing one, has been found by Rawdon-Smith and Sturdy (unpublished). There was a tendency for the differential threshold to be lowest when the adapting and testing tones were of equal loudness. Thus, after several minutes’ exposure to a tone at 100 db. above threshold, the differential threshold at this intensity was often lower than after a period of silence. Zangwill, and after him Jones (unpublished), measured the differential brightness threshold for a small patch within a field, and subsequently gave large numbers of exposures in which the patch might or might not be present ; the subject was required to state whether or not it was there. The number of correct judgments was markedly increased day by day if the subject was informed after each judgment whether he was right or wrong, in comparison with a control group who were not given this information. It was found by Gelb and Granit (1923) that the differential brightness threshold was raised inside a figure drawn on a background ; they concluded that the threshold is affected by factors of configuration and organisation in the visual field. As certain simpler effects of contrast and adaptation did not seem to have been fully controlled, some experiments were under- taken in Cambridge by Craik and Zangwill (1938, in press) which showed a similar rise for figures having the same degree of contrast but much less strong ‘ figural character.’ Certain other results, to be mentioned below, suggest that visual brightness discrimination is very largely peripheral, and in this case higher processes might be expected to have little influence on it. It is probable, however, that central factors are at work in visual localisation, after-effect of seen movement, and binocular fusion. An ingenious proof of the peripheral nature of flicker-fusion was given by Sherrington (1906), who showed that the critical flicker frequency is practi- cally the same for both eyes as for one, though the phase relations of the flicker to the two eyes might be so arranged that one or other was illuminated 294 REPORTS ON THE STATE OF SCIENCE, ETC. all the time. It seemed, then, that the basis of the judgment ‘ flickering ’ or ‘ steady ’ was given by each eye independently, and was not subsequent to central fusion of the two fields. Vernon (1934) found the critical flicker frequency to be affected by conditions which caused binocular rivalry. There remains the third group of factors—those which affect the sense organ itself, by changing either the nature of the stimulus or the sensitivity of the sense organ. It was found that the absolute threshold for touch and the differential threshold for tactile pressure (Grindley, 1936, 1 and 2) and for light in- tensity (Drew, 1936) were raised if the increase was made more slowly ; no rise was found for tactile pain, however. Experiments by Rawdon- Smith (1935) showed indirectly that the differential loudness threshold is higher for slow than for rapid change. Thus a sound which was made alternately to increase slowly and decrease rapidly appeared to become steadily less loud, as the slower increases were not noticed. Direct proof of the same effect is given by Sturdy’s work, at present in progress here. The interpretation of these results is uncertain, and the mechanism may not be peripheral. Explanations might be proposed in terms of a trace- theory or of adaptation ; at least it seemed desirable to consider these factors here, since they are more specific and more closely connected with the stimulus than those considered previously. The peripheral aspects of auditory adaptation—the action of the tensor tympani and stapedius—have been investigated by Hallpike and Rawdon- Smith (1934, 1). The masking of one sound by another is a further example of the interaction of stimuli, and was studied by Lane and Wegel (1929) in the Bell Telephone Laboratories. In visual perception, the presence of black masses or surrounds, or of glare spots, can affect the absolute and differential thresholds, critical flicker frequency, and acuity, in neighbouring areas, as shown by Lythgoe (1935), Vernon (1934) and Stiles (1929). Though similar in its effects to the ‘ masking ’ of one sound by another, the mechanism is probably different. Unlike hearing, visual perception is multi-dimensional, so that simul- taneously presented stimuli are not necessarily superimposed in sensation. It appears more likely that interaction, and contrast effects between different stimuli presented together, are mainly due to the power of these stimuli to change the state of adaptation of the retina in neighbouring areas (Lythgoe and Tansley, 1929). This conclusion is supported by the results of Craik (1938), showing a close similarity between the effects of previous dark or bright adaptation upon intensity discrimination or acuity (unpublished) and those of dark surrounds or glare spots as studied by Lythgoe and Stiles. There is evidence of other interactive processes in the retina; Adrian has facilitated neural summation by strychnine (1928). But whether or not all cases of mutual influence between two simultaneous visual stimuli can be explained in terms of adaptation, spatially regarded, it is certain that previous adaptation of the eye to an illumination different from that at which its brightness discrimination is measured, can cause a marked deterioration in such discrimination (Rawdon-Smith and Mellone, 1935, unpublished ; Craik, 1938). The regularity of these effects, their restric- tion to the stimulated eye, and the failure of attempts to disinhibit them, suggest a retinal origin. Throughout these experiments on hearing and vision, an endeavour has been made to find the main processes at work, to attribute them to their correct ‘ levels,’ peripheral or central, and to correlate those events which appear to be peripheral with anatomical and electrophysiological findings. QUANTITATIVE ESTIMATES OF SENSORY EVENTS 295 Following Sherrington, interaction between two similar or dissimilar sense organs has been employed as a diagnostic sign of the level at which any perceptual process was taking place. Irregularity and disinhibition also provide clues, as noted above. Peripheral factors influencing the frequency and intensity range of the ear have also been investigated by electrical recording of auditory nerve-impulses (Hallpike and Rawdon-Smith, 1934, 1; Pumphrey and Rawdon-Smith, 1936 ; Hallpike, Hartridge and Rawdon- Smith, 1937; Adrian, Craik and Sturdy, 1938), and localisation of pitch discrimination in the cochlea assisted by the same method (Hallpike and Rawdon-Smith, 1934, 2). In the eye, the effects of adaptation are so marked and regular as to give ground for analysing the behaviour of the eye (in regard to brightness discrimination and acuity) into two parts—its behaviour at different test illuminations when maintained in a constant state of adaptation throughout, and its power of adaptation to different illuminations. To borrow an analogy from Lythgoe (1935), the eye behaves rather like an ammeter which can be set to various ranges (adaptation to different intensities) and gives readings over a certain scale of currents when set to any one range (the brightness sensitivity of the eye at various test intensities when adapted to a fixed illumination throughout). It then appears that the eye sets itself automatically to its most efficient range, for any given illumination, if allowed sufficient time to adapt; for it is found that the differential threshold is lowest when the adapting and test illuminations are equal. It has further proved possible, in some work at present in progress, to make monocular comparisons between fields simultaneously exposed to the two eyes, when one eye is bright adapted and the other adapted to some lower illumination or to darkness. Under these conditions, judgment of equality to within a scatter of plus or minus 10 % may be obtained although, owing to the two eyes being differently adapted, the physical intensities may differ five hundred-fold. That so constant a judgment of equality can be made between sensations whose physical stimuli are very widely different indeed, raises once again the problem as to whether sensa- tions may not be in some sense measurable, that is to say whether there may not be some quality of the sensory responses themselves that enables them to be equated, or differentiated in equal appearing steps. It is, at any rate, clear that what value of physical intensity will be constantly equated to another, or just differentiated from another, depends upon many other conditions than the physical intensities themselves. REFERENCES. ApRIAN, E. D.: J. Physiol., 65, 273. 1928. Aprian, E. D., Craik, K. J. W., and Sturpy, R. S.: Proc. Roy. Soc. B., 125, 435. 1938. Craik, K. J. W.: J. Physiol., 92, 406. 1938. and ZANGWILL, O. L.: Brit. J. Psych. (in press). 1938. Drew, G.: Brit. J. Psych., 27, 279. 1936. Ges, A., and Granit, A. R.: Zits. f. Psych., 12,1. 1923. GRINDLEY, G. C.: Brit. J. Psych., 27, 189. 1936, I. Brit. J. Psych., 27, 86. 1936, 2. HA.tpike, C. S., HARTRIDGE, H., and Rawpon-SmiTH, A. F.: Proc. Roy. Soc. B., 122,175. 1937. and RAwDON-SMITH, A. F.: J. Physiol., 81, Pr. 25. 1934, I. Nature, 133, 614. 1934, 2. Lane, C. E., and WeceEt, R. L.: In H. Fletcher—‘ Speech and Hearing,’ 176. London, Macmillan & Co. 1929. LytuHcoE, R. J.: Trans. Ill. Eng.1,3. 1935. ~— and TAnsLEy, K.: Proc. Roy. Soc. B., 105, 73. 1929. 296 REPORTS ON THE STATE OF SCIENCE, ETC. PuMPHREY, R. J.,and Rawpon-Smitu, A. F.: Proc. Roy. Soc. B., 121, 18. 1936. Rawpon-SmitH, A. F.: Brit. J. Psych., 25, 77- 1934. —— Brit. J. Psych., 26, 233. 1936. SHERRINGTON, C. S.: ‘ The Integrative Action of the Nervous System.’ London, A. Constable & Co. 1906. StiLEs, W.S.: Proc. Roy. Soc. B., 104, 322. 1929. VERNON, M. D.: Brit. J. Psych., 24, 23. 1934. III. Statement by Mr. F. Guild. ARE SENSATION INTENSITIES MEASURABLE ? I have been invited to present the case of those members of this Com- mittee whose answer to the question: Are sensation intensities measurable ? is in the negative. ‘To write a report truly representative of the views and outlook of those members would have involved an amount of collaboration which for geographical and other reasons has been quite impracticable. I have therefore made no attempt at such collaboration and this section of the Report is simply an exposition of my own views. But though I am aware that some of my colleagues would approach the problem from quite different angles I am not aware of any significant respect in which their main con- clusions would differ from mine. In respect of these main conclusions I am confident that this section of the Report is representative of the con- sidered opinions of the majority of the physicists on the Committee. It is necessary in dealing with a subject of this kind to discuss not only physical but psychological matters. I cannot claim that in dealing with the latter the terminology is always employed in exactly the same sense as it would be used in the literature of psychology. I must plead with psycho- logists for the same tolerance in this respect that physicists have to extend to them when perusing their writings on psycho-physical problems. I have tried as far as possible to ensure that my meaning shall be clear from the context despite probable inaccuracies in psychological terminology. I am also dealing with broad principles, and to avoid confusion it has been necessary to abstain from frequent digressions to mention and explain away minor matters of detail which may not be in exact accord with some general statement. There are practically no physical or psycho-physical phenomena which are accurately described by any general statement. For example, I describe a ‘ permanent object’ as a relation structure in which all the rela- tions are found to be the same at all times. Of course there is not, strictly speaking, any such thing : temperature variations and other causes produce minor variations of relation-structure in any so-called permanent object. Points of this kind have no relevance to our present discussion and it would merely cloud the issue to bother about them. I trust this will be borne in mind by anyone who may consider that any statement or definition made hereafter is not quite right. I have also been confronted with the difficulty, in writing for readers whose experience is mainly derived from two different fields of study, of deciding what may be taken for granted. I trust this will be sufficient justification if I appear to any reader, or section of readers, to indulge in over-elaboration of obvious points. The same points may not be familiar to all. Measurement. Before proceeding to consider the problem of measurement as applied to psycho-physical problems it is desirable to consider some of the general principles of measurement. Measurement is primarily a device which enables us to use the laws of arithmetic to solve problems relating to phenomenal events. The laws of QUANTITATIVE ESTIMATES OF SENSORY EVENTS 297 arithmetic pertain to numbers and to nothing else: there is nothing inherently numerical in the structure of the phenomenal world. We are, however, so familiar with the description of phenomena in numerical terms (or their formal mathematical equivalents) that the association has become instinctive, and we are apt to imagine that we directly perceive the metrical aspects of nature as inherent constituents of phenomena, existing in their own right, so to speak, and merely observed by us. This induces us to overlook the essentially arbitrary and man-made nature of the association. When this is of an unfamiliar character, as, for instance, when we associate the arith- metical operation X 1/ — 1 with the physical events constituting a phase change of x/2 in alternating current problems and others of a like nature, we recognise it at once as a mere device of the mathematician. In principle it is no more artificial than the more familiar associations of events with arithmetical concepts which underlie all metrical processes. The phenomenal world presents itself to us as a complex relation structure. We need not here enter into metaphysical questions concerning the parts played by our sense organs and by things external to us in determining the kind of relations exhibited by phenomena. We will take the phenomenal world as we find it: a structure of related events, which we find it con- venient to describe and classify in terms of various concepts. We have discovered—and this discovery is the foundation stone of physical science—that by employing a simple but ingenious device some aspects of phenomena can be classified so that certain phenomenal relations existing between members of any such class are ‘ similar’ to the relations ‘between members of the class of numbers on which the laws of arithmetic are based. In arithmetic, these relations are implicit in the meaning assigned by two important symbols, namely =, the symbol of numerical equality, and +, the symbol of the operation of adding one number to another. All other arithmetical operations, subtraction, multiplication or division, involution or evolution, etc., ultimately derive their significance from the operation of addition. In any class of phenomenal aspects of the kind we are considering we can perceive various relations. Further, by performing experimental operations on the things which exhibit the aspects in question we can change the actual relations exhibited. But there is nothing inherently numerical in these phenomenal relations : in order to establish a connection we must arbitrarily associate some unique symmetrical transitive phenomenal relation from among those which may have perceptual significance with the arithmetical relation of equality ; and, further, we must associate some suitable experi- mental operation with the arithmetical operation of addition. If, now, we base our phenomenal classification entirely in terms of this symmetrical relation and this experimental operation we obtain a phenomenal series whose members are related to each other in a similar manner to the members of the series of numbers. We must not confuse ‘ similarity’ as here used with identity. Relations are themselves things which can be classified in virtue of certain characteristics irrespective of the kind of things related by them. A relation may be symmetrical or unsymmetrical, transitive or intransitive, etc., and it is these properties of relations themselves, and not any specific properties of the things related by them, which confer relational similarity or dissimilarity on classes defined by relations. However, it is not here necessary to discuss the theory of similar relations, or go into the conditions which must be imposed on our selected criteria of ‘ equality’ and ‘ addition’ in order that phenomenal and numerical relations may be similar. The important point to be noted is simply that there is no a priori connection between phenomenal structure and number, and that to make L2 298 REPORTS ON THE STATE OF SCIENCE, ETC. a connection we must artificially associate a phenomenal criterion with numerical equality and a phenomenal operation with numerical addition. When we have done this, but not before, we can predict by arithmetical calculation those phenomenal relations which involve only the stipulated practical criteria of equality and addition. A phenomenal class defined by two such practical criteria constitutes a measurable magnitude of the type which Dr. Norman Campbell, in his well-known text-book on the principles of measurement, has termed an A magnitude. Any such magnitude can be measured by processes which do not imply the measurability of any other magnitude. It is true that the practical criterion of equality for any A magnitude will always involve the observation of some phenomenal state or condition which may (and usually does) involve other magnitudes ; but the observational criterion is always of the null type—no difference, or no observable change, in the prescribed state or condition: no numerical relations have to be determined or even be assumed to exist for these other magnitudes. Familiar examples of A magnitudes are length, volume, mass, electrical resistance, and many others which need not be detailed. The practical criteria of equality and addition which define these magnitudes for purposes of measurement are sufficiently familiar to require no description. It is their significance which is not so widely recognised as it might be. It is probably usual to regard the experimental processes of determining equality and of adding as something which we have just found to be a con- venient method of determining quantitative relations inherent in the nature of the magnitudes, whereas these processes are the necessary connecting links between phenomena and number without which there would be no. basis of comparison between the laws of the former and those of the latter. The experimental criteria do not merely enable us to measure a magnitude, they create the magnitude by defining the fundamental relations which are to be the basis of classification. In Physics the general term measurement is not confined to A magnitudes. By suitable experimental processes we affix numerals to many aspects of phenomena to which no operation can be performed having any similarity in relation structure to the operation of addition. Familiar examples are density, specific heat, electrical resistivity, etc. All those things which we ordinarily regard as properties of substances are magnitudes of this type. They are the B magnitudes of Campbell’s classification. We can usually formulate a practical criterion of equality for a B magnitude, but not of addition. Nevertheless the numerals affixed to these magnitudes by our experimental processes associate the members of the magnitude series with the members of the series of numbers in such a way that predictions based on arithmetic will always come out right. This does not, however, mean that measurement without a practical criterion of addition is possible. It results from the fact that B magnitudes aré evaluated simply as a function of the measured quantities of two or more A magnitudes. The density of a substance, for example, is nothing more nor less than the ratio of the numbers which measure the two A magnitudes, volume and mass, associated with any lump of the substance. Its importance is simply that this ratio is found to be approximately constant for all lumps of what we call the “same ’ substance and so is worth noting as a property of the substance. But it would be impossible to do what, for brevity, we call measuring density unless we were already able to measure volume and mass. ‘The associations between phenomena and number required for the measurement of density are supplied, not in practical criteria applicable to density as such, but in™ the practical criteria of equality and addition on which the scales of volume and mass are based. QUANTITATIVE ESTIMATES OF SENSORY EVENTS 299 Strictly speaking, therefore, the only measurable magnitudes are A magni- tudes. Density is only ‘ measurable ’ in the sense that we can arrive at an evaluation of it by processes of measurement—measurement of the A magni- tudes volume and mass ; and any relation involving density is primarily a relation involving volume and mass. Similarly what we call the ‘ measure- ment’ of any other B magnitude is really only the measurement of two or more A magnitudes and the combination of the results by some appropriate formula to give a single number which we term the ‘ value ’ of the B magni- tude in question. Confusion is sometimes caused by the fact that in practice we frequently evaluate A magnitudes by processes which are more appro- priate to B magnitudes. After scales of measurement have been established for many magnitudes, and instruments of various kinds developed for their practical evaluation, it is often easier with the apparatus at one’s disposal to evaluate an A magnitude indirectly from measured amounts of other magnitudes than to measure it directly. For example, electrical resistance, which is an A magnitude, can be measured as such with a Wheatstone bridge system which does not involve measurement of any other magnitude. It can also be determined indirectly from measurement of the potential difference required to drive a measured current through it, and this quite often is the most convenient method. Similarly length, which is pre-eminently an A magnitude, is often measured indirectly by methods involving measurements of the angles of a triangle. But these indirect methods are only possible because we have previously established the scales of measurement of the A magnitudes by direct methods involving only the criteria of equality and addition appropriate to each, and have, then, from measurements made possible by the existence of these scales, deter- mined the various quantitative relations among phenomena which we must know before we can deduce the value of an A magnitude from measurements of other magnitudes. We must clearly distinguish between indirect methods of measuring A magnitudes which we may adopt as a matter of choice after we have accumu- lated various experimental data involving previous direct measurement of the magnitudes, and the indirect methods that are inevitable in the case of B magnitudes, which, because there is no criterion of addition applicable to them, cannot be measured except as the numerical constants in laws relating the quantities of two or more A magnitudes which are found to be associated together in some important class of circumstances. Density, for example, is simply the constant in the experimental law that for any lump of a given substance under specified conditions if we determine the number which is the measure of its mass on the scale appropriate to mass and the number which is the measure of its volume on the scale appropriate to volume the ratio of the former number to the latter is constant. The significance of all measurement is therefore derived from the principles of measurement of A magnitudes. These, very briefly, are as follows : We prepare a large number of samples of some physical entity which exhibits the magnitude in question. In the case of length or mass, for ex- ample, these samples will be material rods or lumps. In the case of a magnitude like intensity of radiant energy the samples of the physical entity exhibiting the magnitude may consist of lamps or other sources of radiation operating under constant conditions. By some method appropriate to the particular case we adjust these samples until they fulfil our experimental criterion of equality. In this way we obtain any required number of ‘ equal’ quantities of the magnitude. We attach the same numeral to each of these quantities, thereby associating them with one number. We then produce other quantities in increasing 300 REPORTS ON THE STATE OF SCIENCE, ETC. order of magnitude by the successive performance of our practical operation of addition on the equal quantities at our disposal. In this way we obtain a series of discrete samples of the magnitude having a relation structure similar to that of an arithmetical progression. ‘Though not essential, it is convenient for identification purposes that the same numerals should be used as names for the corresponding members of the phenomenal and numerical series. ‘The particular arithmetical progression which fulfils this condition is that in which the first term and constant difference is the number which we have arbitrarily associated with each of the equal samples used to build up the series of magnitudes. If for convenience we take unity for this number, our series of magnitudes consists of members, associated by virtue of our practical criteria of equality and addition, with the cardinal numbers I, 2, 3, 4, . . . etc., the number associated with each member being simply the number of our original equal samples of the magnitude which have been added together to obtain it. ‘This series constitutes a scale of measurement of the magnitude in terms of the original quantity as the ‘ unit.’ A scale of measurement would, however, be of little use if its significance were confined to the members of the initial series built up in this way. We want to be able to use the scale to ‘ measure ’ any sample of the magnitude which we chance to encounter. We do this by comparing the unknown sample with the various members of our built-up series to find if it fulfils our practical criterion of equality with any one of them. If we find it to be equal to the member associated with the number 1, we say that 7 is the measure of the unknown sample. There is an obvious difficulty if we cannot find a member in our standard series to which the unknown magni- tude is equal, for we have not defined a practical criterion for any numerical relation other than equality. All we can say in such a case is that the sample measures more than 7 and less than » + 1. In principle no scale of measurement can be continuous because it involves an association with number, which is essentially discontinuous. A scale of measurement can only define and identify a discrete series of quantities. In practice of course we can reduce the gap between successive members of the measurable series by taking smaller samples of the magnitude for our initial collection of equal quantities. If we take them so small that the gaps in our scale are of the same order of magnitude as the uncertainty in determining whether or not our practical test of equality is fulfilled we shall always be able to find some member which seems to be equal to any given sample of the magnitude. In other words we can measure any sample to within the accuracy of our practical tests, though in principle any scale we can construct, however fine-grained, has exactly the same kind of discontinuity as one constructed with large steps. It would clearly be tedious to build up a complete scale of any magnitude from very small samples of the magnitude, and in practice various short cuts based on the numerical relations imposed by our initial definitions of equality and addition are employed, but the fundamental principle is not affected. It is obvious that to state the number which measures any given sample of a magnitude tells us nothing unless we know what quantity has been taken as the ‘ unit.’ This is not necessarily the quantity of the members of the initial collection of equal samples used to build up the scale: as already mentioned we are free to associate any number we like with this quantity, though in the absence of any reason to the contrary it would be natural to associate it with the number 1. Usually, however, there are reasons to the contrary, but these are extraneous to the principles of measurement and are mere reasons of convenience which we need not go into here. ‘There is no QUANTITATIVE ESTIMATES OF SENSORY EVENTS 301 reason inherent in the nature of things why the number 1 should be associ- ated with any particular quantity of any magnitude. What is essential to measurement is that this number shall be uniquely associated with some quantity, and that standard samples shall be available by means of which we can reproduce this association at any time. These standard samples need not be, though they often are, of the exact quantity constituting the unit. They may have any value on the scale defined by the unit. Their function is to make possible the co-ordination of the scales of the various measuring instruments which have to be used in practice. Every measuring instrument has a scale of its own. [If it is constructed on.correct principles its scale will be similar to the standard scale but will not in general be identical with it. By measurement on the scale of the instrument of a standard sample whose value on the standard scale is specified we ‘ calibrate ’ the instrument so that values on the standard scale can be deduced from its readings. It is clear that standards are only necessary for A magnitudes. No standards are required for B magnitudes, whose numerical values are entirely determined by the scales used for measuring A magnitudes. It is obvious that the practical criterion of equality and the practical operation of addition which together define an A magnitude must be applicable at all parts of the scale of the magnitude. In arithmetic it is not only true that 1+ 1+ 1-+1-+1=5, but also that 1+ 4=5 and that 2 + 3 = 5 and also that 5 + 5 = 10,5 + 8 = 13, andsoon. Once we set up a scale of measurement for a magnitude, and begin to apply arithmetic to the results of measurement, the laws of arithmetic will predict that phenomenal relations ‘ similar’ to the numerical relations just quoted will exist among the members of the magnitude series, and these predictions are meaningless unless the practical criteria of equality and addition are applicable irrespective of the ‘size’ of the samples to be compared or combined. ‘Thus it is not enough to have a practical criterion of equality for, say, length which can only be applied to samples of 1 mm., or a criterion of addition of lengths which can only be applied to samples 1 mm. long. From such limited criteria we could construct any number of equal samples 1 mm. long and could add them to form a series in ascending order of magni- tude, but the process would be of no use whatever for measurement. The laws of arithmetic would predict that one group of five of our equal samples, added by our criterion of addition, should be equal to any other group of five similarly added ; but this arithmetical prediction has no phenomenal equivalent if the practical criterion of equality by which our 1 mm. samples are selected is for some reason inapplicable to the comparison of 5 mm. samples. Further, arithmetic predicts that one 5 mm. sample added to another 5 mm. sample is equal to a sample obtained by adding ten of our I mm. samples. This prediction is again meaningless if our process for adding the 1 mm. samples is not also available for adding 5 mm. samples. There is, in fact, an important principle of measurement, which as far as I am aware has never been explicitly stated because it is so obviously ful- filled in most of the measurements carried out by physicists that to state it seems superfluous. This principle is that the phenomenal significance of equality and addition as applied to any magnitude must remain the same to whatever samples of the magnitude they are applied. If this principle is violated by changing the significance either of addition or equality as we ascend the series of magnitudes, we destroy the cross- relation between the series of magnitudes and the series of numbers on which their ‘ similarity ’ depends, and the result, whatever it may be, is not measurement. 302 REPORTS ON THE STATE OF SCIENCE, ETC. The foregoing considerations obviously apply to the majority of the magnitudes measured by physicists. There are some cases in which the application is less obvious, for example the measurement of intervals of time and the measurement of temperature. To discuss satisfactorily the measurement of time would, at the present stage in the development of physical theory, involve a long excursion into Relativity problems ; so as no one has tried to base sensory measurements on any analogy with time measure- ments, there is no justification for devoting space to it here. Suffice it to say that there is no method of measuring time which is not in accordance with the general.principles already laid down. More consideration must be given to the measurement of temperature, for attempts are frequently made to justify the use of certain so-called scales of sensation intensity by analogy with arbitrary scales of temperature. There is no real analogy ; but before this can be demonstrated we must examine the case of temperature. When we observe physical objects by the sense of touch the sensations produced contain various constituents which we interpret as indicating distinctive properties of the objects. Objects may be rough or smooth, hard or soft, hot or cold, etc. ‘The condition of an object in virtue of which it may feel hot or cold to the touch is called its temperature. Experiment has shown many observable relations of a general kind between the tempera- tures of bodies and their measuable properties. The length and electrical resistance of a given rod, for example, are usually greater when the rod feels hot than when it feels cold. In fact, nearly all the properties of a sample of any substance are appreciably different in these two conditions, and in particular, what is called the amount of heat in the sample, which has been identified with the energy of the relative movements of the ultra-microscopic particles of which bodies are known to be composed, is greater when the body feels hot than when it feels cold. When two bodies, of which one is hotter than the other, are brought into close contact, there is a transfer of energy from the hotter body to the cooler, which goes on until the molecular movements in each body are (on the average) equally energetic. We are entitled to use the term ‘ equally energetic’ here, because kinetic energy is measurable quite apart from this property of hotness or coldness of bodies, so that equality, as applied to quantities of energy, has a definite significance. When the transfer is complete, the hotter body has been cooled and the cooler body warmed until neither is hotter than the other. The bodies are then said to be in thermal equilibrium. ‘This is a symmetrical transitive relation between bodies, and so provides a practical criterion of equality for the condition called temperature. But there is no practical operation similar to addition which can be applied to temperature. Obviously there is no method of combining bodies of equal temperature which will provide a series of different temperatures. In this respect temperature is analogous to density : any combination of bodies of equal density results in no change in the value of density. Similarly, any combination of bodies of equal temperature results in no change of temperature. Temperature must therefore be treated as a B magnitude. Our scale of temperature must depend on the measurement of something else.for which a scale of measure- ment is already established. Since the temperature of a body depends on the energy of molecular movement, we may produce our arbitrary association between a series of temperatures and the series of numbers by considering the temperature of a body to increase by equal amounts for equal increments of the energy of molecular movement. If we assume a scale of temperature to be established on this basis it can be shown theoretically that certain physical relations—called thermodynamical relations—are of a very simple form. This is of great convenience to the mathematician, but is of no wisest QUANTITATIVE ESTIMATES OF SENSORY EVENTS 303 special importance to anybody else. We must not make the mistake of assuming that the simplicity of thermodynamic formule on this scale of temperature indicates that we have hit upon a ‘ true’ measure of tempera- ture. The thermodynamic relations will obviously be simple since nothing but dynamical quantities are taken into account in establishing our scale of temperature, which is purely conventional and made to give the simplest possible relation between temperature and energy. Unfortunately this scale is of little use to the practical physicist as there is no practicable method of measuring molecular energies, which have to be deduced from measure- ments of still other things, such, for example, as the properties which would be exhibited by a so-called perfect gas or an ideally perfect heat engine. But as there is no perfect gas and no ideally perfect heat engine practical measurements can only be made with imperfect gases or imperfect heat engines, and corrections which are difficult to determine and in some cases involve assumptions of doubtful validity have to be made. The thermo- dynamic basis does not, therefore, afford a practical means of measuring temperature. It cannot be over-emphasised that measurement is a practical process for obtaining experimental information, and it is not sufficient to be able to formulate the necessary kind of association between a series of magnitudes and numbers; it must also be possible to carry out all the operations involved in defining the basis of the association. Otherwise we have a theoretical scale of measurement with which we cannot measure anything. The thermodynamic scale of temperature is in this category. For the practical measurement of temperature we must seek some other basis. We seek it in some measurable physical property of substances or bodies which varies continuously with temperature. We have an em- barrassing choice of such properties: the length of a rod, the volume of a given mass of a gas or liquid, the electrical resistance of a wire, the e.m.f. _ of a ‘thermocouple’ of two wires of dissimilar metals, the intensity of radiation from a ‘black body,’ etc., etc. All these are measurable by practical processes and all vary with temperature. We may choose any one of them to provide a scale of temperature by deeming to be equal those steps in temperature which accompany equal increments in the measurable pro- perty, or by postulating any other convenient law relating the property with temperature. The mercury thermometer scale is based on this principle, the practically measurable property utilised being the apparent volume of mercury in a glass container. It is as ‘ true’ a scale of temperature as any other, that is to say, there is nothing either true or false about it. Physicists, however, soon wanted to pursue their investigations of thermal phenomena to temperatures both higher and lower than those for which mercury thermometers can be used, and various forms of gas thermometer were evolved. Each of these involves a new definition of a temperature scale based on deeming to be equal the increments of temperature associated with equal increments in the pressure, at constant volume, or the volume at constant pressure, of a constant mass of whichever gas is used, usually hydrogen or nitrogen. When the pressure is low, and the temperature high, the properties of hydrogen approximate very closely to those of the mathematician’s idea of a perfect gas. ‘The scale of the hydrogen thermo- meter, except at low temperatures, therefore agrees closely with the thermo- dynamic scale. But there are disadvantages in using a gas thermometer for everyday thermometry, and in practice other types of thermometer are used. Con- spicuous among these are the platinum resistance thermometer and various types of thermocouple. All of these provide scales of temperature which are essentially independent of each other, though they may, of course, be 304 REPORTS ON THE STATE OF SCIENCE, ETC. empirically related by intercomparison of thermometers of the various types. There is not, however, any a priori formal relation between the scales, and it is necessary to make an arbitrary choice of some one of them as a standard scale for defining the magnitude temperature. Unfortunately, no single type of thermometer can be used over the whole range of temperature in which physicists are interested, and the international temperature scale, adopted in 1927, is a patchwork arrangement involving three essentially different scales. From — 190°C. to 660° c. the standard scale is defined by the variation of resistance of pure platinum wire ; from 660° Cc. to 1063° c. by the variation of the e.m.f. of a thermocouple of platinum and a specified alloy of platinum and rhodium ; and above 1063° c. by the variation in intensity of monochromatic radiation emitted by a ‘ black body ’ radiator. In each of these ranges the temperature scale is defined by postulating a formal law relating the measurable variable (resistance of platinum thermo- meter ; e.m.f. of platinum, platinum-rhodium thermocouple, or intensity of monochromatic radiation) with temperature. The constants in these laws are determined by means of appropriate ‘ fixed points,’ e.g. the temperatures of melting ice, boiling water, boiling sulphur, melting gold, etc. In order to preserve the simplicity of thermodynamic equations and the gas laws, the various scales are brought as closely into accordance with the thermodynamic scale as possible by suitable choice of the values to be assigned to the ‘ fixed point ’ temperatures and by suitable choice of the law of variation postulated for the standard type of thermometer applicable to each range. This does not mean that we succeed in setting up a thermo- dynamic scale. The scale is still in fact made up of several independent parts, each of which is completely defined by the law of variation postulated for the prescribed type of thermometer together with the values assigned to those of the fixed points utilised in determining the constants of the law. All we can succeed in doing by suitable choice of laws and constants is to get a scale which is sufficiently close to the theoretical thermodynamic scale that the laws of thermodynamics based on the theoretical scale are approximately true for measurements made on the real scale. It is of great convenience to do this ; but it is not an essential require- ment of measurement that it should be done, and the scale arrived at in this way is not in any fundamental respect a ‘ truer’ scale of temperature than one based on the postulation of simple proportionality of, say, the resistance of a platinum thermometer and temperature. The fact that there is no operation of addition applicable to temperature qua temperature, prevents it from being measurable in the true sense of the term. All we are able to do, however we may disguise it by theoretical considerations, is to assign numerals to temperatures in accordance with an arbitrary postulated relation to some measurable property of some specified substance or piece of apparatus. When once we have defined some such scale of temperature, temperature becomes ‘ measurable’ in the broad sense in which this word is generally used ; and the laws relating other physical variables with temperature as so defined become open to empirical investigation. It will be clear that the measurement of - temperature is only possible because the relations between temperature and those properties of sub- stances or bodies which we utilise in defining the scale are constant. But how do we know they are constant? It may be thought that con- firmation of the constancy of the relations defining our scale is to be sought in the constancy of the various other relations between phenomena and temperature which we determine by means of our scale once we have established it. This is not so, for such a principle is based on an a priori QUANTITATIVE ESTIMATES OF SENSORY EVENTS 305 assumption of the constancy of natural laws. Any such assumption belongs to metaphysics and has no place in physical science, in which no statement about the behaviour of the universe can be made except on the basis of experimentally determined facts ; and no facts about the relations between phenomena and temperature can be determined until a metrologically sound method of measuring temperature is available. We must therefore be satisfied that our method of measurement is sound without reference to any natural laws involving temperature. The point is that the constancy of the law defining our scale does not require confirmation. It is not an assumption, which may or may not be true, it is a postulate forming part of the conventional framework of physical measurement. ‘The postulated law is necessarily always true for the simple reason that it serves the purpose of defining temperature as ‘ the thing for which this law is true.’ There is no criterion of the magnitude of a temperature (nor of any B magnitude) other than the law by which we choose to define it. It would therefore be meaningless to ask whether the temperature to which our scale assigns the numeral 7 is in fact the same temperature at all times and places. _ Temperature only enters into the physicist’s experience indirectly, in virtue of its effect on the measurable properties of bodies. He is therefore never concerned with it as a thing having existence in its own right which may on occasion assert that existence in ways which are inconsistent with his arbitrary definitions. He is perfectly free to define it by any postulated relation to some one physical property, and so long as he keeps to this definition and makes his measurements in accordance with it no contra- diction between the results of measurement and any other kind of experience can ever arise. Psycho-physical Measurements. With the foregoing introduction in mind, the application of measurement to psycho-physical problems may now be considered. The title of this Committee is wide enough and vague enough to include many matters which are not in dispute, and some misapprehension has been evident during the deliberations of the Committee as to precisely what is in dispute. Those who have contended that methods hitherto supposed by some to lead to quantitative scales of sensation intensity are invalid have been supposed to contend that no quantitative experiments bearing on ‘ sensory events’ are possible. Such a contention would of course be absurd, and I will first consider some important types of psycho-physical measurement which can be, and have been, effected. These may briefly be classed as measurements of relative stimulus efficiencies. An important and well-known example of this kind of measurement is found in the so-called relative visibility function of the eye, which tells us the relative visual efficiency of unit intensity of monochromatic radiant energy of different wavelengths. Briefly, these measurements consist in determining the relative amounts, measured in physical units, of two samples of monochromatic radiation of different wavelengths which are required to make the two sides of a photometric field appear equal with respect to the attribute of brightness. By repeating this for different pairs of stimuli we obtain measures of the relative physical intensities of stimuli of various wavelengths throughout the spectrum which are required to produce equal intensities of the sensation of brightness. The relative efficiencies of radiation of different wavelengths for exciting the sensation of brightness are inversely proportional to the amounts required to produce the same brightness, and it is these relative efficiencies which are usually tabulated or plotted as the ‘ relative visibility function ’ of the eye. 306 REPORTS ON THE STATE OF SCIENCE, ETC. Now what is meant by the physical intensity of a stimulus in these experiments ? We should usually define it as the rate at which radiant energy is incident on unit area of the photometer screen. This is what we intend our physical intensities to mean, but there is a difficulty. Intensity of radiation can be measured as an A magnitude for all samples of radiation of the same spectral quality, because in comparing such samples the pro- perties of the measuring instrument are completely eliminated and equality in its response implies equality of radiation intensity. It is a different matter when we wish to measure samples of radiation of different spectral qualities ; for example, monochromatic samples of different wavelengths. A physical detector of radiation operates in virtue of some interaction between radiation and matter, and in general the efficiency of radiation in producing the response characteristic of the detector varies with wavelength. In other words the sensitivity of the detector is a function of wavelength. It is evident that when we compare samples of radiation of different wave- lengths 4, and A, for which our detecting apparatus gives equal response we have not necessarily got equality in the rates of energy flow Fy, and Fo, but in the products o,,F,, and 6,2#,2, where ca, and o,, are the sensi- tivities of the detector for these wavelengths. Our experimental criterion of equality is not equality of E, but equality of FE, o,, where oa is some function of wavelength. ‘This is true whatever type of detector we use to provide a practical criterion of equality in radiation measurements. In principle we cannot get beyond it. We cannot formulate a practical criterion of equality for FE, alone, but only for the product of £, and another function of wavelength characteristic of the particular instrument used to provide the criterion of equality. Now we have seen that in the measurement of an A magnitude quantitative knowledge of the properties of the instrument used to establish equality must not be assumed. This requirement is fulfilled in the present case if we regard as our measureable magnitude not the quantity HE, but the quantity E, o,. This is, in fact, the quantity measured by any radiometric operation, and it is evident that different types of detecting instrument for which o, is not the same function of wavelength will measure different magnitudes. It so happens that some types of detector can be constructed for which oc, is nearly independent of wavelength. Thermopiles and other instruments with lamp-black receiving surfaces or with nearly-closed radia- tion traps are of this class. In a well-blackened thermopile, for example, o, is so nearly constant over large ranges of wavelength that for practical purposes it may be regarded as constant. With such an instrument the magnitude E, c, may, to a close approximation, be written k E, and it is usual to leave the constant out altogether and regard the magnitude as Fy). For practical purposes this is quite legitimate. Our results are the same to within the errors of observation as they would be if we really did measure Ey; but for an understanding of the significance of a criterion of equality in any metrical process, it is fatal to ignore the factor o, even when it is constant. ‘This is the same kind of philosophical error as we make when we regard the arithmetical ratio n/1 as identical with n, ignoring the division by unity because it does not affect numerical results. The two zs are, however, quite different things ; one may be the cardinal number 2, the kind of number used for counting eggs, whereas the other denotes a relation between two numbers, one of which just happens to be unity. In the same way there is a fundamental difference in significance between the magnitude- E, and a magnitude consisting of the product of Ey, with a function of wavelength, and this difference in significance is not eliminated because in some particular case the function of wavelength is a constant and may be QUANTITATIVE ESTIMATES OF SENSORY EVENTS 307 assigned the value unity. The essential point is that whatever apparatus we use in an attempt to measure radiation intensity we in fact measure a magnitude of which radiation intensity is only one factor, the other factor being a property of the particular kind of physical system on which radiation produces the detectable effect utilised in our measuring apparatus. In the case of a thermopile or similar instrument this second factor is practically independent of wavelength, and for practical purposes we treat the magnitude as though it were Ey alone. With detectors of the photo- electric or photo-chemical type, the instrumental factor varies considerably withwavelength, but any such detectorfurnishes a practical criterion of equality for a magnitude EF, o, where oj is its sensitivity factor at wavelength 4. Now this is exactly what the human eye does in photometric measure- ments involving differences in spectral composition. ‘The part of the eye which interacts with radiation is, of course, a physical instrument which converts some of the radiant energy into other forms, photo-chemical and photo-electric effects being produced which in turn cause stimulation of the optic nerve. We are not at this stage of events concerned with the physics or physiology of the nerve system or with how the physical pheno- mena occurring in the nerves ultimately produce the sensation of light. The peripheral organ is simply a physical detector of radiation, and when used in conjunction with a photometer provides a criterion of equality for a magnitude FE) ca where oa has the same kind of significance as in the other cases referred to above. Now in the case of the eye o, is the efficiency of radiation of wavelength A in stimulating the sensation of brightness, so the magnitude EH, o, has the dimensions of sensation intensity, as of course it must have since it is equality of sensation intensity which provides our criterion of equality for Ex ox. If we could measure EL, 6, we should be measuring sensation intensities ; but while we have a practical criterion of equality for this magnitude we have no operation of addition. All the means employed to vary the intensity of the light reaching the eye from the photometer are applied solely to the beams of radiation and depend ultimately on the operation of addition applicable to E, alone. There is no operation we can perform which would correspond to the addition of quantities of the product £&, o,. It is therefore impossible to deduce any quantitative information about unequal intensities of sensation from photometric measurements such as those embodied in the visibility curve. We can predict that certain relative quantities of energy of different wavelengths will produce equal sensation intensities under prescribed conditions, but that is all, and the whole science of heterochromatic photometry is devoted to establishing this kind of equivalence between stimuli of different physical qualities. The variation of relative sensitivity with wavelength as exhibited by the visibility curve is of course an important constituent of ‘ sensory events ’ and can, as we have seen, be quantitatively described by the results of measurements. The kind of measurement denoted by the term ‘ Colorimetry ’ involves only an extension of the same principle. To discuss colorimetry would carry us beyond the limits of available space. Suffice it to say that in all such measurements the only criterion provided by the eye is one of equality, in this case not only equality in the one attribute of brightness but simultaneous equality in colour and bright- ness. As in ordinary photometry all quantitative operations performed in the measurements are performed on beams of radiation, and do not provide any experimental operation which can be identified with addition of sensa- tions. The results of colorimetric measurements can therefore only be 308 REPORTS ON THE STATE OF SCIENCE, ETC. used to predict equality of colour (under conditions of equality of bright- ness) for various combinations of stimuli. They cannot be used to obtain a quantitative measure of the difference between two different colour sensations. The sets of numerals assigned to any stimulus as a measure of its colour are in no sense a measure of the colour sensation evoked by that stimulus: they are simply a measure of the relative quantities of three standard stimuli which, if combined, would evoke the same colour sensation. The sensory properties which can be quantitatively described by the results of photometric or colorimetric measurements are typical of all those in which controllable stimuli are compared with respect to the relative amounts of them which evoke the same intensity or quality of sensation, or which, more generally, produce the same psychological effect. "The psycho- logical criterion of equality which we impose defines, qualitatively, some psycho-physical magnitude, a B magnitude, defined completely by the ratio of two or more stimulus quantities which fulfil the psycho-physical criterion of equality under prescribed conditions. Such magnitudes can be measured, and their measurement gives important information about ‘ sensory events,’ but such measurements do not serve to place dissimilar sensations on a quantitative scale either of intensity or quality. This of course has always been recognised by leading psychologists. Thus Fechner, as quoted by Titchener (Experimental Psychology, Vol. II, 1905, p. Xxili) says, “. . . the measure of sensitivity, as a measure of mere capacity of sensation, is not to be confused with a measure of sensation itself. Nor does it presuppose any such measure, but only the observation of instances of equal sensations, under like or different conditions of stimulation.’ A type of measurement which has been supposed to provide a measure of sensation intensity is that based on the determination of just noticeable differences of stimulus intensity, usually designated j.n.ds. for brevity. The principle of such measurements is sufficiently familiar to anyone who can be interested in this Report that it is needless to describe it here. The relation between j.n.ds. and stimulus intensity has been determined for various senses and in itself provides valuable information about the opera- tion of the various sensory mechanisms. The ratio of the j.n.ds. at any intensity to the intensity tells us the minimum fractional change in that intensity which is perceptible. We may term it the fractional sensitivity, and its determination under properly specified conditions is not only of interest to the psycho-physicist, but is of great practical importance. Fractional sensitivity is a B magnitude defined as the ratio of two stimulus quantities associated in a specified manner—namely, that the smaller of them is just noticeable when added to the larger. Its evaluation involves only measurement of stimulus intensities, and the association between phenomena and numbers if entirely provided by the scales of measurement established for stimulus intensities. Fechner, however, believed that a scale of sensation intensity could be based on j.n.d. measurements. His contention has received much criticism from the beginning, both from psychologists and physicists, and I find it im- possible to say that psychologists on the whole have been more or less ready to accept its implications than physicists. Despite the criticism which has been lavished on it, however, Fechner’s general principle is still believed by many to afford a basis for measurement of sensation intensities. This. is probably due to the fact that much of the criticism has been on questions of detail or on questions of principle which are not really relevant and the real objections have been lost like a needle in a haystack of discussion. I - QUANTITATIVE ESTIMATES OF SENSORY EVENTS 309 will endeavour to confine attention here to the essential principles of Fechner’s theory and examine these in the light of the general principles of measurement. Let us assume a stimulus to be increased from zero intensity by steps each of which is a j.n.d. Let us denote the j.n.d. at intensity J by AI. The total stimulus intensity at any stage is, of course, the sum of all the ATs which have been added up to that stage. From our experiments we can express AJ as some function of J, say AJ = f(J). When the j.n.d. AJ, is added to the stimulus J, there is an increase in intensity of sensation which we denote by AS;. Similarly when the j.n.d. AI, is added to the stimulus J, there is an increment of sensation AS, and in general, the stimulus increment AJ when added to the stimulus / produces an increment AS in the sensation intensity. Fechner’s first principle is that the total sensation S corresponding to the stimulus J may be regarded as the sum of all the A.\Ss corresponding to all the AJs which have been added to produce the stimulus. If we know the relative magni- tudes of the various As we then, by this principle, have a scale of magni- tude for S. Of course we have no a priori knowledge of the relative magnitudes of the sensation increments corresponding to j.n.ds. at different intensity levels, and Fechner’s second principle is that we are free to postulate an arbitrary quantitative relation between AS, the liminal increment of sensation, and S, the total sensation, say AS = 9(S), where (S) is some arbitrary function. M4 We then have, by postulate, AS = 9(S), and from j.n.d. experiments le Ti(1): Whence eal eS) FQ) treating the small quantities AS and AJ as differentials we get the differential equation d Smeal) eS) =f) and by solving this equation we obtain the relation between S and J, that is to say, the relation between sensation intensity and stimulus intensity. I have put Fechner’s second principle in its most general form. Fechner himself propounded it in the special form in which 9(.S) =k: that is to say, he postulated that all the ASs are equal. Plateau and others have suggested the form o(S) = kS, equivalent to the postulate that AS/S is constant at all parts of the scale. Much discussion has centred round which of these forms of 9(.S) is most in accordance with facts. It does not appear to have been noticed that the very possibility of a factual criterion being applied to discriminate between the two functions is inconsistent with either of them forming a true basis of measurement, for, as we have seen, a scale of measurement is independent of any facts other than those created by the necessary and sufficient conventions postulated in defining the required association between number and magnitude for the scale in question. If Fechner’s second principle is to be accepted it is immaterial what form is given to the arbitrary function 9(.S), and Fechner was quite justified in adopting the simplest one. Now we note that Fechner. aimed at measuring sensation intensity as an A magnitude in terms of units of its own kind: his two principles imply both a criterion of addition and a criterion of equality. In Fechner’s own form of the second principle the criterion of equality is stated explicitly, 310 REPORTS ON THE STATE OF SCIENCE, ETC. but in the general case it is implicitly defined by the form postulated for @(S) taken in conjunction with the criterion of addition. We see at once, without examining either of these criteria in detail, that something must be wrong somewhere. ‘The scale purports to measure an A magnitude, yet its defining relations involve measurable quantities of another magnitude—stimulus intensity. We have already seen that the relations defining the scale of an A magnitude must be independent of any quantitative relation (other than equality) for other magnitudes. Fechner’s principles do not lead to a scale of this kind for sensation, and so do not measure sensation as an A magnitude. Nor do they measure it as a B magnitude. ‘The only way to treat sensation as a B magnitude is to define S by a postulated relation to J. We shall return to this later ; at present we are only concerned to note that Fechner’s principles do not do this. They introduce criteria of equality and of addition of sensation magnitudes, forming the basis of some association of sensation with number independent of the association established for stimulus magnitudes. The S obtained by Fechner’s principles is therefore neither an A magni- tude nor a B magnitude, but has some of the properties of both, which means it has not the necessary and sufficient properties of either. Fechner’s principles do not therefore enable us to measure any magnitude. It may be useful to examine in more detail why this is so. First consider the criterion of equality as applied to some pair of ASs, say AS, and AS,. AS, is the sensation increment associated with a j.n.d. at intensity J,, while A\S, is the sensation increment associated with a j.n.d. at some other intensity J,. These two statements taken together form the only specified relation between AS, and AS,. The relation is not symmetrical: it ceases to be true if AS, and AS, are interchanged. It is therefore not a relation of the kind necessary for providing the practical criterion of equality in a system of measurement. This one consideration alone renders super- fluous all the semi-metaphysical arguments which have centred round the question whether or not equal, in the sense of equally noticeable, necessarily means ‘ really’ equal. A symmetrical transitive relation is essential as a practical criterion of equality in measurement. Further, the proposed criterion of equality, being defined in terms of j.n.ds., has no meaning when applied to quantities of sensation other than those associated with j.n.ds. Thus it is quite meaningless to say that S = AS, + AS, + ...ASy by Fechner’s criterion of equality. We cannot apply the same practical criterion to the comparison of S with AS, + AS, +... ASp as we use to establish the equality of the ASs. Fechner’s definition of equality, in addition to its failure to fulfil the require- ments of symmetry also fails to fulfil the requirement of applicability throughout the scale of magnitude. It is a gross logical error to use ‘ equal ” in one sense for liminal magnitudes and in some quite different sense for supraliminal magnitudes. In regard to sensation intensities we have the ordinary intuitive criterion of equality which we employ whenever we judge that of two stimuli neither is greater than the other. This is the only kind of equality which has any meaning at all sensation intensities, and as we must accept this criterion of equality for sensation intensities in the general field of sensory experience we cannot admit a different one in some special part of the field. We see therefore that Fechner’s second principle, that we may arbitrarily postulate equality (or any other relation which implies an arbitrary definition of equality) for the ASs of aj.n.d. series is wrong. We may not do this because there is already, in our psychological constitution, a criterion of equality which we cannot ignore or modify. Fechner’s postulate is not therefore a postulate but an assumption that the ASs are a mes QUANTITATIVE ESTIMATES OF SENSORY EVENTS 311 equal by this general criterion of equality. We have no right to make this assumption for there is no operation in the determination of a j.n.d. series which corresponds to the operation of judging equality of sensations in the ordinary way. In fact it is really meaningless to enquire if the ASs are equal on any scale applicable to sensation intensities, for the criterion of equality applicable to sensation intensities is not applicable to liminal incre- ments at different intensities. Failure to realise this from the first is doubt- less due to failure to realise that a practical operation for establishing equality is part of the definition of any magnitude. Equality of sensation intensities is established when we compare stimuli neither of which appears greater than the other. But ASs at different parts of the j.n.d. series cannot, from their nature, be experienced under the same degree of stimulation. The operation of establishing equality of sensation intensities is inapplicable, not merely in practice but in principle, to members of the AS series. From the point of view of measurement it is therefore impossible to regard the ASs as samples of the magnitude S. Thus Fechner’s first principle, that we may regard S as the sum of a series of ASs, is invalid, and also, of course, his identification of the ratio A,S/AI with the differential coefficient of S with respect to J; for, of course, the small quantities constituting the numerator and denominator of a differential coefficient must differ in size only, and not in nature, from any other samples of the two variables. They must be measurable on the same scales as other and larger samples, which means that the phenomenal relation defining equality and the phenomenal operation defined as addition must be the same for the differentials as for all other samples of the variables. As this is not true of AS, it cannot be regarded as a small quantity of the magnitude S and A S/AJ has no relation to a differential coefficient. This conclusion, derivable wholly from the principles of measurement, confirms those psychologists who have argued, from quite different premises, that we cannot regard a sensation S as analysable into a series of small quantities added together like the millimetres in a metre stick. A milli- metre and a metre are samples of the same magnitude and differ only in size, but the AS of j.n.d. experiment and S are not: they differ in nature, as they cannot be defined by the same kind of relations. We could go on much longer examining Fechner’s principles in detail, but any one of the objections we have already discussed is sufficient to show that these principles cannot lead to the measurement of any magnitude at all, either of the 4 or B class. Another type of psycho-physical experiment we must consider is that in which a series of three or more stimuli are graded by the method of ‘ mean gradations.’ The principle may be illustrated by an example from vision. The observer is presented with a series of patches of light, all of the same colour, whose intensities are under his control, and is asked to adjust their brightnesses until they form a series so that the ‘ seeming disparity ’ between each one and the next in the series is the same. Brown (The Essentials of Mental Measurement, 1911, 2) calls this ‘seeming disparity’ a ‘ sense- distance.’ When this experiment is performed a relation can be established between the grading so effected and the grading in terms of stimulus intensity (photometric units). The results of experiments of this kind for vision and other senses are usually interpreted as establishing a relation between a psychological magnitude—sense-distance—and stimulus intensities. The grading is supposed to consist of equal sense-distances, and the relation found between these equal sense-distances and the corresponding stimulus intervals is regarded by most psycho-physicists as providing a basis on which a quantitative relation between sensation intensity and stimulus 312 REPORTS ON THE STATE OF SCIENCE, ETC. intensity may be constructed. The underlying assumptions are that a sense-distance is the difference between the sensation intensities corre- sponding to its terminal stimuli, and that the difference between the sensa- tion intensities corresponding to the lowest and highest of a series of unequal stimuli is the sum of the sense-distances between the adjacent pairs of the series. For this to be possible sense-distances must be samples of the same magnitude as sensation intensity. Let us examine the proposed criterion of equality. We define as equal the sense-distances between pairs of unequal stimuli which satisfy a certain subjective criterion. It is un- desirable to attempt to define this criterion at the moment because the words we choose to define it tend to invest it with some one of a number of alterna- tive interpretations. Suffice it to say that there is a condition which the observer attempts to satisfy in experiments of this kind. For our present purpose the nature of this condition is immaterial, the essential point is that the practical operation of producing equal samples of sense-distance neces- sarily involves at least three stimuli of different apparent intensities, whereas the operation of producing equal samples of sensation intensity involves only stimuli of the same apparent intensity. We see therefore that sense- distance, whatever it may be, is not the same kind of magnitude for the purposes of measurement as sensation intensity. The one cannot be expressed on any scale applicable to the other, and it is meaningless to regard them as quantities of the same measurable magnitude. It may be objected that this applies with equal force to the difference of two samples of any magnitude. We cannot produce an example of equal differences of length, for instance, without at least three objects of unequal length while the operation of producing equal lengths involves only objects which appear equal by our criterion of equality for length. The analogy is illusory. Difference of lengths as something expressible on a quantitative scale derives its significance from the association of number and length established by the practical criteria of equality and addition which define length as a magnitude. It merely means the length which must be added to. the smaller of two lengths in order to make a new length equal to the larger of the original pair. We cannot define a process of subtraction independently of a process of addition. We cannot construct a scale of length from units of difference-of-length defined by operations other than those involved in defining equality and addition for length. Similarly we cannot give any quantitative significance to difference-of-sensation-intensity unless we already have practical criteria both of equality and addition for sensation intensity; for all that difference-of-sensation-intensity means, if it means anything, is the sensation intensity which, when added to the smaller of two given sensation intensities, will produce a new intensity equal to the larger. The mean-gradation series as a basis for determining a relation between sensation intensity and stimulus intensity has therefore the same defect as the j.n.d. series. ‘The proposed criterion of equality is not the one applicable to sensation intensities. Thus if sense distance is a magnitude, it must be a different magnitude from sensation intensity. Further, as with the j.n.d. series, the proposed criterion of equality is not a legitimate one for defining amy magnitude. Each sense distance in the series is defined for practical purposes by a pair of dissimilar stimuli, a different pair being applicable in each case. No symmetrical transitive relation can be constructed from such material, therefore no criterion of equality appropriate to measurement can be formulated for sense-distances. So whatever sense-distance may be it is not a measurable magnitude ! Thus if we examine by what right the word equal is applied to the pheno- QUANTITATIVE ESTIMATES OF SENSORY EVENTS 313 menal relations observed in this type of experiment or by what right we assumed that it is differences of sensation intensity which determine the grading, we find that there is no justification whatever in either case. We have here an example of the mental suggestion produced by the repeated use of certain words in a loose and inaccurate manner. The instructions given to observers invariably beg the question of the nature of the operation to be performed. These instructions naturally vary, but they ate certain to contain such phrases as ‘ bisect the interval,’ or ‘ adjust . . . half-way between,’ or ‘ adjust C to be as much brighter than B as B is brighter than A,’ and soon. In all descriptions of the experiment which I have seen, the process is described in terms of this kind which have a definite significance only when applied to magnitudes which we already know how to measure. The observer is in fact instructed to perform a definite quantitative opera- tion, but is not told how to doit. He does the only thing he can do ; that is, adjust the stimuli until he detects some unique character in the relation exhibited by each pair. There is nothing in the operations he actually performs (adjustments of lamps or of sound-emitters, etc.) to tell us what kind of relation it is which he arrives at, and there are no a priori grounds for assuming that differences of sensation intensity, or equality, either of such differences or of any other magnitude, enter directly into that relation. Nevertheless the terms of the usual instructions, by their quantitative implications, suggest the idea of equality and difference as if the operation were exactly analogous to marking off a metre stick into a series of equal parts. If we are instructed to bisect a metre stick, or to arrange three points A, B and C, so that C is as much higher than B as B is higher than A, the instructions have a definite meaning in virtue of the phenomenal rela- tions and operations defining length as a measurable magnitude ; and we can obey the instructions by performing operations in accordance with these definitions ; but if we had not already defined practical criteria for equality and addition of lengths there would be no operation corresponding to ‘ bisection,’ or to the establishment of any other quantitative relation, for lengths. This is the position in the present experiments. Though we have a criterion of equality for sensation intensities we have no operation of addition, and until we have there is no meaning in associating any quanti- tative relation, equality or any other, with differences of sensation intensity. It should be clear, therefore, that the description of this experiment should be couched in language which makes no assumptions about the nature of the relation which the observer is to establish, and that we should avoid all terms like bisect, equal-appearing, sense-distance or others which suggest, by their association with the properties of measurable magnitudes, an unjustifiable interpretation of the operations performed in the experiment. Let us attempt to describe the experiment in terms of the operations performed. We set up three ® similar objects of the type which are perceptible by the sense—vision, hearing or whatever it may be—for which the experiment is to be made. Object is here used in the most general sense to denote anything external to ourselves which is perceptible in virtue of the fact that it is the origin or apparent origin of a stimulus affecting one of our senses. In the case of vision the objects may be lamps, or self-luminous surfaces, or surfaces seen by reflected light. It is necessary to emphasise the fact that the first requisite of the experiment is a set of perceptible objects. If we keep discussing stimuli without reference to their origin we may easily lose sight of the fact that all stimuli reach us from our environ- 3 Three or more, but three is enough to illustrate the principles involved. 314 REPORTS ON THE STATE OF SCIENCE, ETC. ment and that the normal function of perception is to provide information about that environment. So we set up three suitable objects to provide stimuli. We must be able to adjust at least one of the objects with respect to the perceptible property in such a way that the stimulus we receive from it can be varied in magnitude without change of quality. In the visual case, to which I will confine the remainder of the description, we must be able to alter the brightness of the object without changing its colour. There are numerous practical methods of doing this. Let us denote the objects by A, B and C, and suppose that C is brighter than A, and that B is brighter than A but less bright than C. The pair of unequally bright objects A and B present us with a directly perceived phenomenal relation. So also does the pair B and C. We must not confuse these directly perceived phenomenal relations with the quantitative relations between the measured intensities of the stimuli. In order to know anything about the latter relations we have to measure the stimulus values by appropriate methods, but in order to perceive the phenomenal relations we have only to look at the objects. The perceivable phenomenal relations would still be just what they are if we had never formulated a scale of measurement for brightness as a photometric magnitude, in which case there would be no quantitative relations between the stimuli. So we cannot describe phenomenal relations, as intuitively perceived, in terms of quantitative concepts. ‘They are simply those aspects of the objective world, as directly perceived, in virtue of which we differentiate objects and groupings of objects from each other. Returning to our experiment, we perceive the phenomenal relations between objects A and B and between B and C, which we will denote by A.B and B.C, the notation conveying no implications about the nature of either relation. We also notice a relation between these relations. We find that as we vary the brightness of B between those of A and C not merely do the individual relations A.B and B.C change but so also does this cross relation. We are not required to describe (nor indeed are we able to describe) how it changes. To say that the perceived interval AB is greater, equal to, or less than the perceived interval BC is merely to use words before we know what they mean in the particular application. The relation changes in some respect which is directly apprehensible to us: that is all we can say. In general the rela- tion is not one that we recognise as having any special significance, but as we go on adjusting the brightness of B to various values we find that there is one value, and only one, for which the relation we are now speaking of, the relation ‘between the relations A.B and B.C, is such that we recognise those relations as having sameness in some respect which has a unique significance in perceptual experience. This is the criterion we have been trying to satisfy: the experiment is finished except for the measurement of the stimulus values, i.e. the actual brightnesses of A, B and C, by the appropriate photometric methods. The experimental psychologist may object that to look for a recognisable relation between undefined relations A.B and B.C is not what the observer is asked to do, and there is therefore no reason for supposing that this is what he does. It is the only thing he can do. The instructions usually given him, as already stated, are couched in terms of operations for which no meaning has been defined. Whether or not he thinks he understands them and believes himself to be carrying them out is of no consequence. He cannot in fact carry them out. All he really gathers from the instructions is that. there is some unique perceptual criterion by which the stimuli may be arranged, and assumes when he has found such a criterion that it is the one the instructor means. Thus, although in many psycho-physical experi- QUANTITATIVE ESTIMATES OF SENSORY EVENTS 315 ments the instructions are of vital importance because there are several different things the observer may do depending on his interpretation of them, in the present case the nature of the instructions has no influence on the experiment because there is only one thing the observer can do if he performs the experiment at all. The foregoing is, in all essentials, an exact description of how experi- ments of this kind are carried out. The extension of the process to build up a series of stimulus intervals each of which is related to the next in order in the same way as A.B is related to B.C clearly implies no new principle. The application of equivalent processes to hearing or other senses only involves differences in practical details. We observe that the experiment may be described without introducing the concepts of equality, difference, bisection, etc. ‘The only concept required is that of ‘ recognisability ’ as something which confers on some relations a unique significance not possessed by other relations of the same general type. We also note that it has been unnecessary to make specific mention of sensation intensities. In our description sensations remain in the background, as they do in ordinary life, serving their normal purpose of making us aware of phenomenal relations among the objects in the perceptual field. Of course there must be psychological relations corre- sponding in some way to the observed phenomenal relations, but we pay no attention to these in performing the experiment ; we simply accept the information they afford us about the external objects. ‘The mental attitude of the observer during these observations is the normal one of perception, not of apperception. He is observing the objects, not his own sensations : his criterion of the accomplishment of his task is not the deliberate identification of any unique relation among his sensations, but the recog- nition of a unique relation exhibited by the objects. Recognition appears to me to be the key-word for the interpretation of this experiment. What does recognition mean? We may confine atten- tion to the intuitive recognition of phenomena, the kind of thing that happens when I know a friend as soon as I see him, or when I know my own house as soon as [ come within sight of it, or know that a certain sound is the call of the cuckoo as soon as I hear it, or know tea by its taste, or lavender by its smell, and so on. What is my friend, what is my house, what is a cuckoo, or tea, or lavender? Each of these is nothing more (at least as far as I am concerned) than permanent, or quasi-permanent, relation- structures perceivable against a background of ever-changing phenomenal relations. We look out (and hear out, feel out, taste out, and smell out) on a world consisting of a medley of directly perceivable phenomenal relations of a great variety of different kinds. Some of these relations keep changing and attract but fleeting attention. Others remain apparently unchanged for a long time, and these we group into relation structures which constitute enduring phenomena such as people, houses, cuckoos, tea and so on, the ‘ objects’ or ‘ things’ which endure. Now any such relation structure may contain many different types of relation. Not all of these involve magnitudes, but many of them do, and of these some will be extensive, like length, mass, brightness, etc. Of the relations involving such magnitudes, some will involve absolute extension while others will involve only relative extensions. Absolute is here used in the ordinary everyday sense. There is, of course, no criterion for absolute extension of any magnitude in the fundamental sense of absolute. Absolute extension in the ordinary sense is itself relative—relative to some universally applicable standard, such as the length of the standard metre, or the mass of the standard gram, or the brightness of a surface emitting a lumen per sq. cm., 316 REPORTS ON THE STATE OF SCIENCE, ETC. and so on, which is not necessarily a member of the group of phenomena We are perceiving at any given moment; whereas by relative extensions we mean relative not to an external fixed standard but to the other extensions of the same magnitude within the perceived group of phenomena. In a relation structure composed of lengths, those relations involving absolute extension determine what we vaguely call the size of the structure while those involving only relative extensions, in this case the ratios of the various lengths, determine what we call the shape of the structure. Of two such structures it may happen that the relations involving absolute lengths are different but that all the relations involving the ratios of lengths are identical. The two structures are of the same shape but of different sizes. ‘The terms size and shape are so convenient for discriminating between properties depending on absolute extension and those depending on relative extension that it will be useful for our present discussion to extend them to apply to relation structures involving any extensive magnitude. We may use the term relation-shape to signify the sum total of those properties of a relation structure involving any extensive magnitude which depends only on the relative extensions of the samples of the magnitude comprising the structure, and relation-size to signify the sum total of those properties of the structure which depend on the absolute extensions. For instance, consider a‘simple relation structure involving two masses A and B of 20 and 30 gm. As this particular structure does not include the universal standard gram, the relations of the masses A and B to this standard are not part of the structure, so the masses of A and B are absolute extensions of the magnitude mass. Of course the symbols 20 gm. and 30 gm. used to denote these absolute masses are meaningless unless we determine the relation between each mass and the standard gram, but this is determined from the examination of other relation structures of which the standard gram is a part. So long as attention is confined to our present structure the masses are absolute. Relations exhibited by this structure include (1) B—A=r10 gm.; (2) B+ A=50 gm.; (3) B/A =1°5. If we have another structure involving masses C and D of, say, 40 and 60 gm., the corresponding relations are : (1) D— C= 20 gm.; (2) D+ C= 100 gm.; (3) D/C =1°5. Relations (1) and (2) involve absolute masses ; relation (3) only relative masses. These two structures have the same relation-shape but differ in relation-size. In the same way, two relation structures involving, say, brightnesses, may have the same relation-shape provided the ratios of the brightnesses comprising one structure are the same as the corresponding ratios in the other structure, but will differ in relation-size if the absolute brightnesses of the corresponding members of each structure are not equal. Of the physical relations constituting a relation structure of the kind we call an object, the relation-sizes are properties of the body just as much as the relation-shapes ; but they are not of equal importance for intuitive recognition. The complete relation structure of an object can never be perceived on any single occasion. It is a synthesis of many relations observed in different ways at different times, and usually involves several of our senses. We can never see a house; we can only see the visual relations exhibited by the particular bit of the outside or inside of it which comes within the field of view at one instant. In order to become acquainted with all the visible properties of a house we have to perform numerous acts of seeing at different times and in different conditions. Even then we have not apprehended the whole house: we have to feel all over it for such tactile relations as it may exhibit—hardness or softness of its various parts, roughness or smoothness, etc.—and perform all sorts QUANTITATIVE ESTIMATES OF SENSORY EVENTS 317 of measurements on it to obtain the absolute extensions of the various extensive magnitudes which are involved in its relation structure. A relational construct built out of all this material is what we mean by ‘ the house.’ From the moment when we first notice that some of these re- lations are repeated on different occasions of observation, we get the idea of a permanent physical entity firmly rooted in our minds ; and thereafter every sense impression which presents relations that may, without evident contradiction, be regarded as part of a self-consistent relation structure is linked in our minds, by the psychological process known as association, not merely with the other relations comprising the structure but also with this co-ordinating idea of a permanent physical entity—an object. ‘Then, when at any time we perceive any reasonably important group of the relations for which such associative bonds have been established, it at once calls up the idea of the whole object, and we recognise the object as a house, or a cuckoo, or tea, or whatever it may happen to be. Now the strength of an associative bond is reinforced by every repetition of an experience of the relations involved. It is only after many repetitions of similar experiences that the association becomes instantaneous and automatic as is the case with those associations by which we recognise the presence of a well-known object or well-known type of object. It is clear therefore that of all the relations pertaining to a relation structure, those will be most important for recognition which are most often observed, and will be those phenomenal relations of which our sense-impressions are least affected by the variable conditions in which our miscellaneous observations are made. Now if we consider the visual sense, it is at once obvious that those phenomenal relations involving absolute size will apparently vary every time we change our distance from the object. It appears bigger in the perceptual field from one distance than from another and those apparent sizes vary continuously as the distance changes and do not cluster round any norm. Any relation involving absolute size will be but rarely repeated in our miscellaneous observations of the object, and the associative bond will be too feeble for us to recognise the relation as part of the relation structure of the object. On the other hand, those phenomenal relations involving only the relative lengths of different parts of the object are apparently unchanged by distance, and the same relations will be observed every time we view the object from any given direction. Strong associative bonds between these relations and the idea of the permanent objects are established, and we regard the experiencing of any important group of them as ‘ seeing the object.’ In so far, therefore, as its distribution in the dimensions of space is con- cerned, an object is recognised by its apparent shape, not by its apparent size. Apart from possible differences in the relation structure of other magnitudes associated with the object, and which we are not considering at the moment, objects of the same apparent shape observed separately are absolutely indistinguishable from one another by direct perception whatever may be their sizes. A series of objects of the same shape, but in ascending order of size, seen in succession present merely a selection of the appearances which any one of them would present as we approach it from a distance. It is this which makes sameness of shape a uniquely important phenomenal relation for perception. If we are shown a large number of triangles of miscellaneous sizes and shapes, each is a relation structure of the same general character, involving the same number of samples of the same magnitude, length, arranged with respect to each other in the same manner, i.e. end to end and completely enclosing a space. In addition to perceiving the relation structure constituting each triangle we 318 REPORTS ON THE STATE OF SCIENCE, ETC. perceive various relations between these individual structures. Between any pair selected at random there will in general be an obvious difference both in size and shape. If we have a really large and miscellaneous selection to examine, we shall see between various pairs practically every possible kind of phenomenal relation that can exist between triangles. In general there will be nothing unique in any of these relations, nothing to which we can attach more importance in the case of one pair chosen at random than in the case of any other pair. There is only one relation which will strike us as unique: if we find that there are two or more triangles of the same shape we can pick them out at once as a group characterised by the unique relation of having a recognisable property common to all its members. Sameness of relation-shape is a symmetrical and transitive relation between relations or relation structures, and it might seem that it is this property which makes it uniquely important to perception. I don’t think there are grounds for this view. We do not in perceiving phenomenal relations analyse them into their logical classes. The unique significance we attach to a pair of triangles of the same shape when we pick them out from a medley of pairs exhibiting other relations between their shapes is instinctive. It does not depend on a conscious realisation that if (triangle) A is of the same shape as B, B is also of the same shape as A, and further that if B is the same shape as C' then A is also of the same shape as C. It might be sug- gested that we do realise these facts almost simultaneously with the perception of the triangles, but even if this were so only a mathematician would also realise that the facts were of any unique importance as properties of a relation. I can see no reason why any phenomenal relation should have a unique significance for intuitive perception apart from association ; and if we find, as we actually do from experience, that some particular kind of relation has a unique significance it must be because it has become indelibly associated in our minds with some unique type of experience of outstanding frequency of occurrence. Broadly speaking, practically the whole of our perceptual experience consists of the observation of permanent objects and the ever-changing relations which ,these permanent objects, regarded as self-contained unchanging entities, may enter into with each other. The changing relations between permanent objects are ephemeral ; the relations between the moving motor-car and the mile posts are different every time we look: but the relation structures constituting any given aspect of the permanent objects, the motor-cars and mile posts themselves, do not change, and are perceived every time we observe the same aspect of the objects, whatever the circumstances of observation. Any particular relation between different objects is therefore observed very rarely as com- pared with the relations which characterise objects themselves, and which, for a given object, are the same at all times. This is why ‘ sameness’ of relation structure is perceived far more frequently than any other relation between relations. Jt is the relation between the perceived relation structures of any object on different occasions. It may be objected that when we identify the same object on different occasions we are not really concerned with a relation between separate relation structures observed on these occasions, but are merely perceiving the one identical structure every time. This, however, is to confuse the relation structure which constitutes any phenomenon with the abstract relations involved in it. A phenomenal relation structure is not a structure of abstract relations, but of instances of relations. For example, suppose we arrange three billiard balls so that each ball is distant ten feet from each of the others and that we also arrange three other billiard balls in the same way. We have here two phenomenal relation structures in which all the QUANTITATIVE ESTIMATES OF SENSORY EVENTS 319 relations, including those involving absolute length, are the same. But the two relation structures are not identical ; they are separate instances of the same relations. If we regard three balls arranged as above as a phenomenal unit—a ‘ thing "—the two relation structures are not the same thing but two different things, each with its own identity, even if there is no possible test by!which we can distinguish one from the other, as there will not be if all the relations in the two structures are identical. In describing phenomena as relation structures we do not mean a con- glomeration of abstract relations, but a grouping of actual instances of relations. Some modern philosophers are apt to forget this and regard the universe as built up of abstract mathematical material. But we cannot build reality with abstractions: there must be ‘things’ to relate before we can have an example of any relation. It is true that these ‘ things ’ are themselves resolvable into relation structures involving relations between more elementary ‘ things,’ and so on indefinitely, but we never reach a stage at which we find relations without ‘things’ to relate. This is not because methods of physical analysis do not go far enough. If our present ultimate things—electrons, positrons, etc.—were split into a million other things, and each of these into a million others, we should still be in the same position. Any actual instance of a relation must have things in it to be related. All the relations in the relation structures constituting two billiard balls may be identical, but the relation structures are not identical ; the ‘ things’ in them are different: it requires twice as many of them to make two balls as to make one. Therefore when we say that two objects have the same relation structure we do not imply identity. This is clear enough when we are considering two or more objects like billiard balls whose non-identity can be proved by their simultaneous existence in different places. It is not so obvious in the case of the relation structures of which the same object is composed at different times. Here the elementary ‘ things ’ which enter into the various relations in the structure are the same things on all occasions, or at any rate we have no way of knowing that they are not. But we have no way of knowing that they are. Our idea of a permanent object is based on the inter-consistency of an enormous number of acts of perception involving different aspects of the object and different relations to other objects. In any single act of observation only a small part of this material is presented to us, and its perception is a self-contained experience. We perceive a phenomenal relation structure, that is all. On a subsequent occasion we also perceive a phenomenal relation structure. How do we correlate these experiences ? Neither of them in itself contains anything to indicate that it is a repetition of the ‘same’ experience. As far as immediate perception is concerned we must regard the relation structures perceived on separate occasions as separate structures, and we can only correlate them by means of cross relations between these structures. The correlation of successive appear- ances of the same object therefore depends on the same principle as the correlation of the appearances of two or more objects simultaneously observed. In the latter case the relation structures are separated in the dimension of space and in the former in the dimension of time, but for the comparison of perceived relations this difference in the dimension of separation is of no importance. Perceptions separated in time are com- parable in consequence of memory which reproduces the relation structure of a past observation for comparison with the relation structure of a present one. The smaller the gap in time between the observations, the more accurately is the memorised structure reproduced. As a matter of fact the comparison of the relation structures of simultaneously existing objects 320 REPORTS ON THE STATE OF SCIENCE, ETC. also depends, at least to a considerable extent, on memory. We cannot simultaneously apprehend all the material in a complex perceptual field. This is well known to workers in experimental psychology. Our attention fluctuates rapidly to and fro over the field and the composite impression of which we are conscious is really a blend of memories of features perceived at slightly different instants. Thus the difference between what we ordinarily regard as simultaneous perception of phenomenal relations and successive perceptions is only one of degree. The recognition of the successive appearances of an aspect of any permanent object does not depend on any mysterious power of identifying one relation structure on different occasions, but is simply an instance of the relation we call sameness between relation structures which are separate in perception but are brought together, by memory, for simultaneous comparison. We do not give the relation this name because it implies mathematical similarity or for any reason of that kind. It exists among phenomena as directly perceived, and implies no knowledge of quantitative relations which may or may not be establishable by the indirect processes of physical measurement. It is only in relation structures comprised of measurable magnitudes that mathematical relations have any meaning, and when our perceptual criterion of sameness is applied to relation structures of this kind we have to find empirically the mathematical relation to which it corresponds. We call our relation sameness simply because its unique importance in perception is derived from its continual presentation to us in association with the idea of ‘same’ objects; but it will, for the reasons already discussed, retain its unique significance whenever we encounter it, whether in successive appearances of the same object or in the successive or simultaneous appearances of different objects. The appearances of two or more objects which happen to exhibit this unique relation between their perceived relation structures will be recognised as the ‘ same’ appearances just as if they were in fact successive appearances of some one object. An important conclusion follows from these considerations which has a bearing on many problems of sensory experience. This is that any phenomenal relations that may be of special significance in cases of simultaneous perception will also be of special significance when the phenomena are separately observed, and vice versa. We have already seen that in phenomenal relation structures involving lengths, owing to the varied conditions in which our everyday experience is obtained, the only relations in the structure which are significant for recognition of the object are those which determine the relation-shape of the perceived structure, while those which determine the relation-size play no part in recognition ; and that for such structures the recognitive relation of sameness involves only relation-shape. It is easy to see that this must also be the case for structures involving other perceptible extensions. The apparent brightnesses of the various parts of recognisable permanent objects depend on circumstances of observation just as much as their apparent sizes. The illumination by which objects are seen varies over an enormous range, and their perceived brightnesses vary accordingly. Obviously no relations involving absolute brightness will be recognised as uniquely associated with any object. Similarly with sound, any sound pattern, such as a musical chord or a piece of music which we recognise as the ‘same thing’ when we hear it on successive occasions may be heard on different occasions at different distances from the source. Its apparent loudness will vary enormously in our experience of it, and there will be no particular loudness in any way uniquely identified with the pattern. QUANTITATIVE ESTIMATES OF SENSORY EVENTS 321 It is needless to discuss other senses ; in general the varying conditions of perception, coupled also with the variations which take place in our sensory sensitivities, make it impossible to form an associative bond between any perceptible extensive property and the ‘thing’ which possesses it. In all cases our perceptual criterion of sameness must involve only the relation-shape of the perceived relation structure and not its relation-size. This much is obvious; but the psycho-physicist is concerned with establishing relations between our sensory criteria and the measurable physical properties of the world, and we must enquire what sameness of perceived relation structure implies with regard to the corresponding physical relations established by processes of measurement. The arbitrary criteria for associating phenomenal relations with numerial relations which, as we have seen, are the basis of any metrical scale, establish a correlation between phenomena and number of such a kind that whenever a given numerical relation between measured magnitudes is repeated, the corre- sponding phenomenal relation will also be repeated. It follows that if the relation shape of the relation structure comprising the metrical relations is repeated so also will the relation shape of the phenomenal relation structure, and vice versa. Therefore, since the recognitive relation of sameness involves only the relation shape of the phenomenal structure, the measur- able property which is recognised must involve only the relation-shape of the metrical structure, in other words the relative quantities of any measur- able magnitudes associated with objects. When we observe a miscellaneous collection of objects of the same type, those which appear to be characterised by the same ratios of the measurable magnitudes will be instinctively classed together in virtue of our perceptually unique relation of recognisability. Returning now to our experiment on ‘ mean-gradation ’ we see that the criterion is nothing more than the recognition of the sameness of the relation structures consisting respectively of the bright objects A and B and the bright objects B and G, and that owing to the way in which the relation of sameness has come to acquire its unique importance (by asso- ciation with appearances of ‘ same’ objects of constant physical properties under varying conditions of perception) this perceptual criterion should only be satisfied if the measured brightnesses of A and B and of B and C are in the same ratio. Our example, and most of the discussion, has been in terms of visible phenomena, but the conclusions are applicable to all experiments of this kind. The grading of a series of stimuli in such experiments should result in steps such that the ratio of each stimulus to the next in order is constant. The measurement does not depend on equality of any sensory magnitude describable either as difference in sensation intensity, or as intensity difference regarded as a magnitude by itself. The concept of sense distances, assumed to be equal for the steps of such a series, is entirely illusory. Nothing is involved but the recog- nition of a relation between the relations which relate the physical intensities of adjacent pairs of stimuli, a relation which does not imply equality of any magnitude, either objective or subjective, but owes its special significance to association with the perceptible aspects of the various kinds of permanent objects or things in terms of which we are accustomed to interpret our experience. Our perceptions will always result in our assigning properties to objective things, and, as we have seen, should result in our grading these things, as far as extensions are concerned, in terms of relative magnitudes. Magnitudes observed on separate occasions will be graded by perception in the same way as when observed simultaneously, because the only basis of comparison in such cases is memory, and the same relation determines the comparison as in simultaneous observation. ‘The position we assign to M 322 REPORTS ON THE STATE OF SCIENCE, ETC. any stimulus, experienced by itself, against the background of memorised experiences of other stimuli of the same kind will be the same as we would assign to it in a series of stimuli experienced simultaneously. If we mis- takenly estimate sensation intensities on the unjustifiable assumption that the sense distances in a so-called mean-gradation series are equal, we are led to the mistaken conclusion that sensation intensity tends on the whole to increase by equal amounts for equal increments of the ratio of stimulus intensity (or that S varies as log J) ; then when we experience some stimulus by itself, as when we observe a single bright object or hear a single sound, we tend to estimate the sensation intensity on the same false (or rather meaningless) scale by comparison with memories of previous experiences of the sensation intensities corresponding to known stimulus intensities. Actually we are not comparing sensation intensities at all, but are attempting to place the stimulus in a series of its memorised predecessors, graded in terms of the recognitive relation of ‘ sameness ’ of relative intensity ratios. It cannot be over-emphasised, because it is so consistently overlooked, that when we perceive a light or a sound or any other perceptible thing our resulting impression, and the judgment we base on it is not of our sensations but of those features of the environment from which we receive the stimulus. That is the normal function of perception: our judgment is about the objective intensity of the stimulus, and if we say of the members of a group of stimuli graded by the mean-gradation criterion that the intensities “ appear ’ to differ by equal amounts, when in fact they do not differ by equal amounts, we are merely asserting that our senses are misleading us and providing wrong information about the phenomena observed. But our senses do not grossly mislead us (except in unfamiliar circumstances). In general they inform us reasonably correctly of the relations exhibited by the phenomena: that is what they have been evolved for. It is only if we misinterpret these relations that we are led to false conclusions. So, when we are trying to estimate the loudness of a sound, for example, it is not the subjective intensity of our sensation we are estimating on any scale, true or false, but the objective intensity of the sound. Whatever the actual relation may be between sound intensity and sensation intensity it merely serves the purpose of leading to an intuitive judgment about the objective sound, and if we so interpret this judgment as to grade the sound on any scale of magnitude but the right one—the scale of stimulus intensi- ties—we are not discovering any fact about sensation intensities, but are simply making a mistake about the objective intensities. ‘Thus the pre- valent idea that the sensations of brightness, loudness, etc., vary approxi- mately as the logarithm of the stimulus intensity is devoid of any basis and is neither proved by, nor even suggested by, mean-gradation experiments. All these experiments can tell us is whether, on the whole, the operation of our sensory system is such as to provide us with reasonably accurate information about the relation structure of the objective world. If any single act of perception provided us with absolutely accurate information about the relations perceived, all mean-gradation series would consist of intensities each in the same ratio to the next for the reasons we have dis- cussed. But we would scarcely expect any act of perception to provide absolutely accurate information about objective relation structure. As we have already remarked, what we mean by the true objective relation structure is a synthesis of an enormous number of relations observed in different ways at different times. For any individual act of perception to provide information absolutely consistent with this synthetic whole would require a uniqueness of relation between stimulus and response only obtainable QUANTITATIVE ESTIMATES OF SENSORY EVENTS 323 from a mechanism of absolutely constant properties, deliberately designed and constructed for the purpose. We do not look for such machine-like behaviour from sensory mechanisms, made of living material necessarily influenced by changes in our bodily conditions, and not designed, in the usual sense of the term, but simply developed by the gradual processes of evolution to become more and more serviceable to us. Evolution is a gradual process. Our sensory mechanisms are doubtless much better suited for providing us with the kind of information we want from them than were those of our early forefathers, but are just as surely less well suited for that purpose than they might be, and presumably may be some day. Although, as I have tried to emphasise, we do not consciously judge our sensation intensities in an act of perception but judge the objective intensi- ties, the sensation intensities are nevertheless the only basis of the judgment ; and there must be a relation-structure in the psychological content of the sense impression corresponding to the relation structure of the phenomena perceived. We cannot expect from the nature of our sensory machinery that exactly similar psychological relation structures will be produced by the same phenomenal relation structure on every occasion and in all conditions of observation. Repeated experience of the observation of any permanent phenomenal relation structure will, however, establish a norm among the various psychological structures produced by it at different times, and this norm will be the psychological structure which produces in us the reaction which we interpret as perceiving the objective structure. Now if on any individual occasion this same objective structure produces a psychological structure different from the norm we shall ‘ perceive ’ not the actual pheno- menal structure, but another one for which the actual psychological structure is itself the associated norm. In other words our judgment of the external objects- will be in error. Our judgments would, in fact, very frequently be in error from this cause if they depended entirely on the immediate sense impression ; but in the ordinary observation of the world our mistaken impressions are corrected by another effect of association, known to psychologists as regression towards the phenomenon. When we receive a sense impression from a familiar object (or from one which we assume, correctly or otherwise, to be a familiar object) which is not quite consistent with the phenomenal structure that we normally associate with the object, associative reflexes originating in accumulated experience of the relation structure which ought to be perceived, come into operation and correct our impression either to what it ought to be or to something much nearer this than it would be in the absence of such associative reflexes. We are not concerned here with either the physiological or psychological machinery of phenomenal regression, but merely have to note that it is one of the most important agencies in preserving the correspondence between our judgments of phenomenal relation structures and the structures themselves despite a somewhat imperfect correspondence between our immediate sensory re- actions and the objective conditions which evoke them. Now it is evident that the effectiveness of this corrective agency— phenomenal regression—since it depends on correlative associations, will be most strongly developed for the observation of familiar phenomenal group- ings encountered regularly in everyday life. Further, it cannot work miracles. Even a familiar phenomenal grouping, if observed under con- ditions for which the immediate sensory impression differs too much from the norm associated with it, will be misjudged and will seem different from what it really is. From its nature, phenomenal regression will be inoperative in circum- stances which do not call up the correlative associations on which it depends. 324 REPORTS ON THE STATE OF SCIENCE, ETC. This is the case in the majority of experiments of the kind we are considering in which artificial groupings of a few bright objects isolated against a dark background, or a few isolated sounds produced in unfamiliar ways, are perceived. There is nothing in such systems to evoke the correlative associations involved in phenomenal regression, and judgment will depend almost entirely on the immediate sensory reaction. The psychological relation structure due to the direct effect of the stimuli on the sense organ, if for any reason it does not happen to be the norm associated with the particular phenomenal relation exhibited, will not be ‘ corrected’ towards this norm : we shall simply judge, wrongly, that we perceive the phenomenal relation for which the impression we receive is the associated norm. Con- sequently if all the relevant properties of the sensory system are not constant throughout the range of intensity covered by the series of stimuli we shall not judge the stimulus relations correctly. Our criterion will still, however, be the perception of sameness of relation shape in the phenomenal relation structures consisting of adjacent pairs of stimuli, but our judgment when this is achieved will be in error. The extent, therefore, to which any experiments of this kind fail to grade stimuli in a geometrical progression is simply an indication of the extent to which the sense organ under investigation fails to tell us the truth. The particular causes of this failure in any particular circumstances are the business of the physiologist and possibly, also, the psychologist; but neither compliance with the law of geometrical progression, nor the departures from it which may be observed, can lead to the discovery of any quantitative relation between sensation intensities and stimulus intensities. The ‘ apparent ’ phenomenal structure will always be that for which the immediate psychological structure of any instance of perception has been related as a norm by the associative bond of integrated experience. In particular, any two phenomenal structures will be * perceived ’ to have the unique relation of sameness, whether they really have or not, if in a given act of perception the psychological relation structures which they evoke are related to each other by the psychological relation which is the norm associated with sameness of objective relation structure. Thus, any difference which may ever be manifested between the ‘ apparent ’ relations of phenomena and the ‘ true’ relations, do not involve any law of variation of sensation intensity with stimulus intensities, but only arise from the fact that from some cause, either adventitious or systematic, the phenomenal relation structure under observation is not producing the normal psycho- logical relation structure which is associated with these phenomenal relations by the totality of our experience. The reason for it not doing so in any particular case may be physiological or psychological or both. We cannot expect any physiological mechanisms, such as those involved in our receptor organs and neural systems, to exhibit constant properties at all intensities of stimulation. We do know, however, as an empirical fact, that over the range of conditions typical of the bulk of our ordinary experience, our individual perceptions give us a fairly faithful account of phenomenal relations ; so within this range the differences between apparent and true phenomenal relations cannot be great. We should, however, expect to find more important departures at intensities lower or higher than those for which the bulk of our associative experiences are obtained. We should therefore expect in mean-gradation experiments to find stimuli to be graded by perception in the ratio of their intensities, or nearly so, within the range of ordinary comfortable perception, but to exhibit departures from this relation at high and low intensities. This is, in general, what is found when the experiments are carried out. a QUANTITATIVE ESTIMATES OF SENSORY EVENTS 325 As the phenomenal relation involved in the grading is sameness of the relation between adjacent members of the series, it is independent of the size of the intervals, and the same criterion should be operative even if the intervals are made so small that we are just able to distinguish between the members of adjacent pairs. If the intervals are less than this, the perception of pairs, and therefore of any relation at all between pairs, is impossible. Thus so long as the members of a mean-gradation series are distinguishable from each other they are related by our criterion of sameness of interval. But we have now reached what is, in effect, a j.n.d. series, from which we see that the successive stimuli in such a series must be graded in intensity by the same law as the members of a mean-gradation series, i.e. in accord- ance with the apparent ratio of their intensities. Apart from adventitious causes due to difference in the experimental conditions in which the two types of experiment are carried out, the departures from a true grading in terms of objective stimulus ratios should depend on the same physiological (or other) systematic causes, and should be of a similar character. The results of actual experiments of these two types are, in general, as predicted by the foregoing considerations. In the case of vision, both equal-appearing-interval series and j.n.d. series grade stimuli very nearly correctly in accordance with relative intensity over the very large range of intensity associated with normally comfortable seeing, departures from the true grading only becoming serious at low and excessive intensities. ‘The results for sound are less definite, as a perusal of the section of this Report prepared by Dr. Semeonoff will show. This is also to be expected. Owing to the very indefinite clue to direction given by our auditory apparatus, we do not hear a ‘ picture ’ of our environment in which the constituent sound waves reaching us are definitely associated with the sources or reflecting objects from which they come. Hearing is rather like seeing in a thick mist, in which we may perceive the general direction from which light is coming but see no objects. With sound therefore we are usually unaware of the exact origin of the stimulus and feel that we are simply immersed in a nebulous ‘ cloud’ of sound surrounding our heads. But this nebulous cloud is not the sensation ; it is the objective environment which, in virtue of the sensation it evokes, we ‘ hear,’ just as when immersed in a translucent mist the nebulous cloud of luminescence we see is not our sensation, but constitutes the objective environment of whose presence we are made aware by our sensations. What we hear is outside us in exactly the same sense that what we see is outside us, a point that seems to be entirely overlooked by many writers on audition. However, owing to the nebulous nature of the objective world, as perceivable by hearing, it is relatively rare for us to make a definite association between any sound pattern and a unique source. It is only on the occasions when we know, for other reasons, that some object is the origin of the sound, as when we simultaneously see and hear a person speaking or an orchestra playing, and so on, that we make such an association at all. The associative bonds between any psychological relation and a corresponding phenomenal relation are likely, on this account, to be much less strongly developed for audition than for vision, where the bonds are reinforced by almost every experience. Nevertheless, such uniqueness for recognitive purposes as any auditory relation can have must be derived from that fraction of our experience in which associations are established ; and must, for the reasons we have discussed, correspond to sameness of relation-shape depending in audition, as in vision, on the apparent relative intensities of stimuli and not on their absolute magnitudes, and must tend, as in vision, to approximate to a recognition of the true relative intensities within a reasonably wide range of intensity. 326 REPORTS ON THE STATE OF SCIENCE, ETC.’ The data on sound, despite wide differences in the results obtained by different experimenters using different experimental devices, definitely tend to show that stimulus gradings by the j.n.d. and mean-gradation methods are very similar and that in both cases the grading places stimuli approximately in a geometrical progression over a large range of intensity, the two results which we have predicted. The results depend solely on the unique recognitive significance of sameness of relation-shape of apparent relation structures and provide no information whatever about quantitative relations of sensation intensities. All we are able to say about the correspondence which must exist between psychological relation structures and the phenomenal relation structures to which they are linked by association is that the psychological relation between psychological relation structures in virtue of which we are aware that the relation of sameness of relation-shape exists between phenomenal relation structures must, like the phenomenal relation itself, be symmetrical and transitive and so cannot involve absolute extensions of any psychological magnitude : ‘also, that sensation intensities must increase with increase of stimulus intensity. But we cannot deduce the law of variation. The association of sensation intensity and stimulus intensity may be of an elastic kind, as in fact we know it to be from the phenomena of adaptation. Why do we assume that there must be a quantitative relation between stimulus and sensation? Quantitative relations only hold for relation structures composed of measureable magnitudes. Our familiarity with the multitudinous quantitative relations established by the methods of physics, and by the cruder but equivalent methods we employ in estimating measur- able magnitudes in everyday life, induces the feeling that every relation between things for which the relations greater or less are significant must be a quantitative relation expressible by its numerical equivalent. ‘This feeling has apparently led to the universal conviction that sensation intensity, to which the terms greater or less are obviously relevant, has an inherent association with number only awaiting discovery. It is assumed that between two sensation intensities S, and S, there is a ‘ true’ relation, S,/S_. =n, where m is some number, and that the problem we are up against is to find some way of determining 7 in any given case, or of deducing it indirectly from the result of some experiment which depends on it. As I see it this is not the position. There is vo relation S,/S, =m until we have defined S as a measurable magnitude by a practical criterion of equality and a practical operation of addition. Unless this is done—and no one argues that it can be done—there is no basis of association between members of the class of sensation intensities and members of the class of numbers, and no meaning in a numerical relation between sensation intensities. Equality of these intensities presents no difficulty, but no operation analogous to addition is possible. Every psychologist agrees that this is so ; but it is not realised that without it we are not merely unable to discover quantitative laws involving sensation intensity, but that there are not in fact any quanti- tative laws to discover. The theory here advanced to explain the significance of the unique relation which determines the grading of stimuli by the mean-gradation method as derived from associative experience, is put forward solely on the grounds that when one is endeavouring to destroy the foundations of any firmly rooted belief it is desirable, where possible, to lay the foundations of a new one to take its place, and not to confine oneself to purely destructive criticism. ‘The mistake must not, however, be made of regarding the alternative explanation as an integral part of the case against the old one. Whether the explanation here given proves to be acceptable or not, the QUANTITATIVE ESTIMATES OF SENSORY EVENTS 327 case against the prevalent interpretation of these experiments is complete. It depends simply on the fact, demonstrated in the beginning, that they do not provide any practical criteria for associating any sensory magnitude with number in the particular manner which is essential for measurement, so no relation between sensory magnitudes and stimulus magnitudes can possibly be derived from them. If the explanation I have suggested should prove wholly, or in any important aspect, unacceptable, we are simply left for the time being with no explanation of the experiments. The old one will not do; and the sooner writers on psycho-physical problems stop describing and interpreting their experiments in terms of sense distances and sensation scales the sooner will it be possible to seek a true interpretation of their results freed from the tendentious influence of a falsely suggestive terminology. The foregoing general considerations cover all the other types of experi- ment in which the observer associates numerals with perceived stimuli composed in different ways, such for example as the well-known experiments of Dr. L. F. Richardson and his colleagues. This Report is already too long to permit discussion of such methods in detail, but it can be said of all of them that whatever may be the criterion by which the observer assigns a number to an observed stimulus relation, or makes some equivalent decision in connection with it, such as marking a point on a line to correspond to the ‘ position’ of a percept in a series ranging between two extremes, it cannot consist of the intuitive perception of some quantitative relation between psychological magnitudes, for there are none to perceive. In all these experiments, as in those we have con- sidered more fully, the guess, estimate, or judgment, whichever it is, relates to stimulus magnitudes and not to sensations. It may be a guess or estimate based on direct association with known cases of the same type of stimulus relations. ‘This is a process we perform almost every day when we estimate lengths, weights, temperatures, etc., without measuring them. It depends merely on direct association, and in the case of those things with which we are very familiar may often be effected with considerable accuracy. Those experiments which are not explainable on the basis of direct associa- tion must have for their criterion the perception of sameness of relation shape between some elements of two or more relation structures. The foregoing discussion centres round the possibility of measuring sensation intensity as an A magnitude—that is, as something expressible in terms of units of its own kind. A few words must now be devoted to the possibility of treating sensation intensity as a B magnitude, defined by an arbitrary relation to stimulus intensities. In the first place, assuming it can be done, it would serve no purpose whatever. It would merely result in our being able to say that the intensity of sensation corresponding to the stimulus J is the intensity of sensation corresponding to the stimulus J, which would not help us much in any psycho-physical problem. The utility of a temperature scale, which, as we saw earlier, is defined by an arbitrary relation to the properties of a standard thermometer, is that the thermometer can be used to measure the temperatures of other bodies. It would clearly be useless to define the temperature of a resistance thermometer as a function of its resistance, as we do, if it could only be used to measure its own temperature. All the definition would mean is that the temperature of the thermometer when its resistance is R ohms is the temperature corresponding to a resistance of R ohms. This would be the position as regards sensation intensity. We could not use the sensation scale established by the definition in one standard sensorium to measure the sensations in other people’s sensoriums, because our criterion of equality 328 REPORTS ON THE STATE OF SCIENCE, ETC. for sensations is private. We cannot establish sensory equilibrium between people as we can establish thermal equilibrium between bodies. Each person would be a sensationmeter only capable of measuring its own sensa- tion, like a thermometer only capable of measuring its own temperature. It could provide no information about anything. However, we cannot even have whatever satisfaction there might be in establishing this perfectly useless sensation scale. As we saw when con- sidering temperature, in order that a magnitude may be defined in this way it must be possible to postulate a one-one relation between the magnitude to be defined and the measurable magnitude to which it is to be related by the defining relation ; and that we are not free to make any such postulate unless, from the nature of the case, it is certain on a priori grounds that the defined magnitude can never enter experience except as ‘ the thing defined by the adopted relation.’ There is no one-one correspondence between sensation intensity and stimulus intensity. Sensation intensity enters experience directly, in its own right so to speak, and we know that, owing to adaptation, fatigue, or various other causes, the same stimulus may evoke sensations of markedly different intensity on different occasions. So we cannot define a scale of sensation intensity as a postulated function of stimulus intensity even were it of the slightest use to do so. The analogy with temperature advanced by some psychologists is entirely fallacious. But what about the average sensation intensity corresponding to a stimulus J? May not this be treated as a B magnitude? Over how long a period are we to take this average ? Obviously if the whole of an observer’s life is to be included there will be a one-one correspondence between mean S and J, and we are free to postulate any law we like to define a relation between them. But what have we achieved? We cannot use this scale to measure the individual S corresponding to J on any particular occasion. It gives us no information other than that with which we started, that the mean sensation intensity corresponding to any intensity of stimulus is just whatever we have chosen to say it is. We must conclude therefore that sensation intensity is not measurable either as an A magnitude or as a B magnitude. It is not measurable in any sense of the term. IV. Notes on Mr. Guild’s statement by members of the Committee. A. By Dr. R. H. Thouless. (1) This account of what is meant by ‘ measurement’ is excellently clear. I think ‘ measurement’ is primarily the physicist’s term and I am willing to accept what they say as to what the word means, and I do not think it in any way restricts the possibility of quantitative experiment in psychology if it is agreed that it is not ‘ measurement of sensation.’ (2) The account of Fechner seems to make his account of the matter much more clear and rational than it really was. Thus with reference to ‘ Fechner’s second principle’ (p. 309), I cannot find that Fechner formulated any such principle in the Elemente. He assumed it, according to my reading, without realising what he assumed, by stating Weber’s Law in the form: dy = K .d8/8. (3) It is obvious that Fechner thought he could establish measurement of sensation in a sense which is indefensible. I am not sure that Mr. Guild disposes of a possible defence that what is really possible is a B measurement of sensation (for a single individual, under specified conditions of stimulation, QUANTITATIVE ESTIMATES OF SENSORY EVENTS 329 with a single kind of stimulus) using equality of just noticeable differences as a convention of measurement parallel to the use of equality of tempera- ture differences causing equal volume changes of thermometry. Anyway it is obvious that the restrictions are such that measurement in this sense would be of little practical scientific value. (4) I am not convinced by the argument of pp. 317 ff. Surely apparent shapes change with different angles of vision as do apparent sizes at different distances. (5) I think Mr. Guild would agree that most of the quantitative experi- ments psychologists do when they attempt to ‘ measure sensation ’ could be done equally well and equally meaningfully if they gave up that assump- tion. He does say this, but I should like to see it emphasised. It con- siderably narrows the apparent difference between his view and the oppos- ing. For example: ‘ Thus the prevalent idea . . .’ (p. 322) seems to me to exaggerate this difference. I should like to see added that if Mr. Guild’s view is accepted and the mean-gradation experiment is merely a report of sameness of relations, it is nevertheless a real question whether if one arranged, let us say, a series of electric lamps so that each successive pair had the same brightness relation between them, whether this series would be a geometrical or arithmetical series of physical intensities. The phrase ‘ is devoid of any basis’ seems to suggest that there is no real problem, whereas I think Mr. Guild would agree that there is a real problem but that it should be stated in other terms. 23.6.38 B. By Dr. L. F.. Richardson. Mr. Guild has made a logical analysis of the relation between sensation and stimulus. ‘Those whose chief reliance is on logic, take risks of passing over assumptions without noticing them. Mr. Guild’s analysis may be summarised in three steps :— Step I. Is sensation an A-magnitude? No! Step II. Is sensation a B-magnitude? No! Step III. Therefore sensation is not a magnitude of any sort. The tacit assumption is that the A and B magnitudes are the only kinds of magnitudes that can exist. But there is abundant experimental evidence (vide Dr. Semeonoff’s report) from several independent investigators in England and America that intuited magnitudes exist. Of course A-magni- tudes are usually the most reliable ; and A and B magnitudes, taken together, are the only sorts of magnitude which are respectable in practical physics, except for the estimation of tenths of small divisions. It is also evident that intuited magnitudes are subject to variations with the occasion and with the observer ; variations so large that they would not be tolerated in practical physics. But if, as Mr. Guild avers, A and B magnitudes are not available for sensation, then intuited magnitudes are not to be despised. The progress of psychology towards the status of a quantitative science is more likely to be advanced by experimental exploration of the relations of intuited magnitudes than by refusal to allow them to be considered. Some people wish to see the word ‘ measurement ’ restricted to mean the determination of A and B magnitudes only. If that were done it would be necessary to point out that a mere terminological convention must not be allowed to prejudice discussions about the existence of magnitudes other than those called A and B. There is a remark, independent of the foregoing considerations, to be made about Mr. Guild’s Step I. He avers (on p. 310) that the method of M 2 330 REPORTS ON THE STATE OF SCIENCE, ETC. equal appearing intervals does not yield an A magnitude because the rela- tion of ‘ appearing equal’ is not symmetrical ; because the sensations are tied to stimuli which cannot be interchanged. But let us suppose that the experiment is conducted, in the customary manner, by two persons one of whom, called the experimenter, alone knows the stimulus values, while the other person, called the observer, alone judges equality of appearance. In these circumstances the relation of ‘ appearing equal’ is purely intro- spective. Is it not symmetrical ? 25.6.38 C. By Mr. T. Smith. If by measurement we mean the association of numbers and properties by a rational systematic procedure such as the physicist employs (and—to say the least—this restriction appears necessary to avoid misunderstanding), I agree with Mr. Guild that sensations are not measurable. Apart from measurement there may be personal associations of numbers as well as of other concepts with sensations, but this in itself is not of great importance since the associations are peculiar to a single individual, though the fact of association may be of psychological interest. By training, the numbers in these associations can often be modified and controlled so that they correspond more or less to the numbers of some measurable property. In the absence of special training the numbers assigned to the members of any collection will vary notably from one observer to another. Ability to guess fairly accurately what measurement will give is an accomplishment of considerable utility, and this perhaps represents the nearest approach we can get to measurement on a sensory basis. Simple tests I have made on a number of subjects suggest that the ‘ scales,’ if the word is permitted, of untrained observers show marked differences from one another. Consistency only began to show when four objects were presented, and substantial agreement was reached on the magnitude which corresponds to the cross-ratio of four points on a straight line. In these experiments the individual scales were therefore projections of a common scale. While this is consistent with Mr. Guild’s suggestion that likeness in a relation is a recognisable quality, it also suggests that Mr. Guild’s interpretation of this relation in stimulus terms may be too narrow. A constant ratio of the stimuli from similar-appearing pairs is only one of a number of possible cases, and this or any other choice must be justified experimentally, and not by an a priori argument. 27.6.38 D. By Dr. Wm. Brown. While appreciating the excellence of Mr. Guild’s discussion of the question ‘ Are Sensation Intensities Measurable ? ’ and agreeing with most of his arguments directed against Fechner’s position, I am not satisfied that he has demolished the case for the direct measurement of contrastes sensibles (Delboeuf), commonly translated as ‘sense distances.’ ‘ Sense distances ’ can be bisected with some degree of accuracy provided that the subject carries out the experiment a large’ number of times under ap- preciably constant conditions. In other words, the result is a statistical central tendency of statistical constancy as checked by its probable error. I find nothing in Mr. Guild’s argument that would move me to withdraw anything that I have written on this matter in Chapter I of The Essentials of Mental Measurement. On the other hand, I do realise that a very much fuller discussion of the problem is needed, in the light of recent experi- mental work, and I am glad that the Committee is asking for a further year, during which it can deal with the question more fully. 1.7.38 QUANTITATIVE ESTIMATES OF SENSORY EVENTS 331 E. By Dr. }. H. Shaxby. It seems clear that the members of the Committee as a whole come out by that same door as in they went, and that no general complete agree- ment can be reached. The question we have been asked to decide, if not mal posé, at any rate turns to some extent on the definition of the term “ quantitative.’ Mr. Guild’s article confirms this view. With its conclusions I concur on the whole, but I do not feel that his demonstration that sensory magni- tudes are neither of class A nor of class B, disposes of the possibility that they may none the less be magnitudes (of class X say). That they are not magnitudes of practical importance to physicists or physiologists I agree, but this need not in itself consign them to limbo. I suppose we should all agree that the conception of magnitude (like other conceptions) has a sensory basis ; one thing is greater than another because it looks larger or sounds louder or smells stronger. The measurement of the stimuli producing these different sensory effects has been the task of physics, and in the process it has been found that the introspective sensory estimates, while in the main giving a correct grading, are rough and often not even self-consistent; they have therefore been superseded by the “objective ’ physical modes of measurement by: scales, balances and what not. But this very fact indicates the nature of these intuitive estimates ; no less than our balance, etc., they are methods of measuring stimuli. We look at the sensory experience directly, so to speak, instead of looking at the vernier or spot of light or stopwatch. In so doing we perform a measurement of the stimulus and our result is such a measurement, more or less accurate, and nothing more psychologically fundamental than that ; certainly not a measure of the sensation itself. It is true that we use changes of sensation as our indicators of changes of stimulus, and if we have inde- pendent measures of stimuli we are entitled to use these to deduce the laws which our sensory indicators follow, e.g. (if Weber’s Law holds) that our series of just noticeable differences functions as a logarithmic scale of stimulus-intensities. But this in no way justifies us in supposing that we have measured the intensity of our sensations. ‘To do so is merely to lay down a postulate. Postulates may be useful or necessary ; Euclid’s are necessary if we are to cross the pons asinorum. But this sensory postulate is mere lumber, for we make no further use of it. It does not help us to compare stimuli because the intuitive method of doing this does not require it, and it leads to no information about the physiological mechanisms of sense. 2.7.38 (V) Statement by Prof. F. Drever. THE QUANTITATIVE RELATION BETWEEN PHysICAL STIMULUS AND SENSORY EVENT. In my turn I have been invited to present the case for an affirmative answer to the question whether sensation intensity is in any sense measur- able, at the same time dealing with the main objections urged from the opposite point of view. As the arguments on the other side are based on general principles, so must also the answer to these arguments be similarly based. The most fundamental principle of all is the principle that both physicist and psychologist have a common starting-point in the world of sense experience, and a common aim in the fuller and clearer understanding of this world of sense experience. To that we shall return later; in the meantime let us consider Mr. Guild’s arguments. 332 REPORTS ON THE STATE OF SCIENCE, ETC. While Mr, Guild professes to eschew metaphysics his whole description of the phenomenal world as composed of ‘ relation structures,’ and a large part of his discussion of measurement is essentially metaphysical. It is perhaps true that ‘there is nothing inherently numerical in the structure of the phenomenal world,’ but it is true only because numeration is a con- ceptual process involved in our cognition of the phenomenal world. It is our knowledge of the phenomenal world that is really in question, not the phenomenal world as such. At this point let me correct a piece of bad psychology which crops up again and again in Mr. Guild’s statement, especially in its later parts. He says ‘ we are so familiar with the description of phenomena in numerical terms that the association has become instinctive.’ It is not a matter of association at all, except in so far as particular number names are associated with the number concepts—‘ four ’ for the Englishman, ‘quatre’ for the Frenchman, ‘ char’ for the Hindu. This associationism runs riot all through the later parts of the statement, and in so far as it affects the argument the psychologist rejects it iz toto. The thinking of relations is never explicable in terms of association. The exposition of the principles of measurement is based on the distinc- tion drawn by Dr. Norman Campbell between A magnitudes and B magni- tudes, and only A magnitudes—that is magnitudes which can be measured by processes which do not imply the measurability of other magnitudes— are, strictly speaking, measurable. This would appear to mean that, strictly speaking, measurement reduces itself to enumeration, and that spatial magnitudes, or even lines only, are measurable. This is virtually a reduc- tion of measurement to pre-history conditions. 'The important considera- tion from our present point of view is that it leads to the view that in order to establish a quantitative relation between two entities both entities must be measured each in terms of some unit appropriate to itself. Hence in order that we may be able to establish a quantitative relation between the intensity of the physical stimulus and the intensity of the sensation, we must be able to measure not only the physical stimulus in physical units but the sensation in sensation units. This is, I believe, an error, but it is an error which has been made by many psychologists as well as Mr. Guild, and the physicists for whom he speaks. The theoretical possibility of measuring sensation intensity as such measurement was interpreted by Delboeuf, that is as distance on an imagi- nary scale of sensation intensity, as, for example, a loudness scale, must be admitted, even if we accept Mr. Guild’s contention. Greys differ in degree of brightness, sounds differ in degree of loudness. Theoretically at least an individual can construct for himself a scale of brightness of greys, in which each grey appears a definite and equal distance away from the next grey on either side, and any new grey can be assigned its place on the scale. As regards an analogous loudness scale the position is somewhat compli- cated by the fact that loudnesses are not co-presentable in time, as the greys are, for reasons depending on the nature of the phenomena themselves, and here neither the scale itself nor measurement by means of the scale will be so accurate. The scale is an imaged:scale as it were. But the theoretical position is not thereby affected. In the case of the loudness scale the specification of the various points on the scale including the zero will necessarily be in physical terms: to this point and to what it involves return will be made presently. What must be emphasised here is the theoretical possibility of the construction of such scales. The practical consideration upon which the most serious criticism of such scales can be based is that in strictness they are scales for the one individual only who constructs them, and for the time at which and the conditions, subjective a ae QUANTITATIVE ESTIMATES OF SENSORY EVENTS 333 and objective, under which they are constructed. It must, I think, be admitted that the subjectivity of a scale of this sort damns it from a practical point of view. But the subjectivity is a necessary consequence of the ille- gitimate demand that there must be a sensation scale in sensation units as well as a physical scale in physical units before sensation can be related to physical stimuli by way of measurement. The fact is that the demand, and indeed the greater part of Mr. Guild’s argument relevant to the demand, implies a metaphysical theory even when it is not explicitly metaphysical. We can only free ourselves from the incubus of this metaphysic by an entirely new start. First with regard to the evolution of measurement. The concepts of number and of magnitude are the two fundamental, and in part independent, notions from which measurement springs.. Measurement necessarily involves comparison. Nothing is measured in terms of itself, except in the case of mere enumeration, and even that is not measurement, where there is not some comparison explicit or implicit. It is true that we can make the statement that there are twenty individuals in a group, when the number 20 may be taken as a measurement of the group in terms of the individual, but the notion of measurement in any such case only arises when the comparison of one group with another is in question, which means that ‘ greater,’ ‘ less,’ and ‘ equal’ are the basal ideas in all measurement. The questions ‘ how much greater ?’ or ‘ how much less ? ’ are raised later. The first answers to these questions are given in terms of the other, ‘ twice as large,’ ‘ half as large,’ and so on—and the principle at once emerges that everything is measured not in terms of itself, but in terms of something else. The next step in the evolution of measurement is the measurement by means of standards which may be applied to the various magnitudes to be compared, and at this stage there is nothing incongruous in measuring space in terms of time and time in terms of space. Actually, for practical purposes all measurement is ultimately in terms of space. Our only means of measuring time, in fact, would seem to be in terms of space. When time units have been determined in this way, it becomes possible to measure motion—both constant and variable—in terms of time and space. It would appear, therefore, that there is no difficulty whatever in finding analogies to the measurement of sensation intensity in terms of stimulus intensity without the necessity of measuring each in the first instance in terms of its own units. ‘There would rather seem to be difficulty in finding analogies to the kind of measurement Mr. Guild contends for in the initial measurement of any aspect of the phenomenal world. Moreover it would also appear that if B is measurable in terms of A we only seek to devise a scale in terms of B units provided we wish to use B to measure something else. Measurement is not an end in itself. It is merely a means to the more exact representation, and therefore clearer understanding of the various connections and relations in the phenomenal world, which is of course the world of our sense experience. The ‘ relation-structure ’ which Mr. Guild mistakes for the phenomenal world is a conceptual construct, arrived at as a result of, and by way of, measurement of the objects and events in the experienced world of sense. We may take it then that in order to relate quantitatively stimulus intensity and sensation intensity, it is not necessary that we should be able to measure each in units of the same kind, but merely to measure the one—the stimulus intensity—and determine the manner in which the other—sensation intensity—varies in dependence upon the former. That loudness is a function of sound intensity does not admit of any doubt whatever, and a similar statement can be made of brightness, sweetness, and so on, in relation to their respective physical stimuli. The essential problem is the 334 REPORTS ON THE STATE OF SCIENCE, ETC. determination of the functional relationship between the intensity of the stimulus and the intensity of the sensation as an aspect of our experience of the stimulating object. At this point another objection must be urged against Mr. Guild’s argument. He appears to assume that it is our per- ceptual experience of the object that we are attempting to correlate with the intensity of the stimulus, whereas it is merely the sensation aspect of that experience, abstracted from the experience as a whole. CONCLUSION. The Committee feels that the matter presented above is of great interest and value to those whose task it is to make measurements, mental and physical, and of importance sufficient to justify the Committee asking for reappointment to consider whether the views put forward are, or are not, irreconcilable. The Committee therefore asks to be reappointed for one year without grant. PLYMOUTH LABORATORY. Report of the Committee appointed to nominate competent naturalists to perform definite pieces of work at the Marine Laboratory, Plymouth (Dr. W. T. Catman, C.B., F.R.S., Chairman and Secretary; Prof. H. GRAHAM CANNON, F.R.S., Prof. H. Munro Fox, F.R.S., Dr. J. S. Hux.ey, F.R.S., Prof. H. G. Jackson, Prof. C. M. Yonce). THE grant of £50 was paid over to the Marine Biological Association on February 11, 1938. Miss M. J. Dibb, King’s College, London, has been nominated to occupy the Association’s table at the Laboratory from July 12 to 29 ; she proposes to work on Protozoa parasitic on Polychetes. Dr. Margaret W. Jepps, Glasgow, will occupy the table from October 1 to December 31, 1938, and will carry out research on the structure and life- histories of Foraminifera. The Committee asks for reappointment, with renewal of the grant of £50. ZOOLOGICAL RECORD. Report of the Committee appointed to co-operate with other Sections interested, and with the Zoological Society, for the purpose of obtaining support for the ‘ Zoological Record’ (Sir Stoney F. Harmer, K.B.E., F.R.S., Chairman; Dr. W. T. Caiman, C.B., F.R.S., Secretary; Prof. E. S. Goopricu, F.R.S., Prof. D. M. S. Watson, F.R.S.). THE grant of £50 was paid over to the Zoological Society on May 13, 1938, as a contribution towards the cost of preparing and publishing Volume LXXIII of the Zoological Record for 1936. The report of the Council of the Zoological Society for 1937 shows a further depletion of the ‘ Record Reserve Fund ’ due to excess of expenditure . over receipts. The need for help from the contributing societies therefore continues, if the publication is to be carried on. The Committee accord- ingly asks for reappointment, with the renewal of the grant of £50. aN ARTEMIA SALINA 335 ARTEMIA SALINA. Report of the Committee appointed to investigate the progressive adaptation to new conditions in Artemia salina (Prof. R. A. Fisuer, F.R.S., Chairman ; Dr. A. C. FaBErGE, Secretary ; Dr. F. Gross, Mr. A. G. Lownpes, Dr. K. Matuer, Dr. E. S. Russett, O.B.E., Prof. D. M.S. Watson, F.R.S.). AN outline of the programme of these experiments for the year 1937-38 was given in the last report of this Committee, presented at the Nottingham session of the British Association. This programme has been followed in all essentials. A total of 27,440 nauplii have been tested, representing an amount of work considerably in excess of any one previous year. The testing and breeding of the material has been carried out almost entirely by Miss S. B. North. The distribution of the tested nauplii among the six generations and the seven lines used this year is shown in Table I. The data for lines C,, Cz, C,, Cs, and C, are supplementary to those of the previous year. In addition, two new lines have been started, the reciprocal crosses of C, and C,, two lines which had been selected through five generations last year : C, is a line which had shown a particularly strong and steady improvement in resistance. It has been pointed out in the two previous reports that the chief factor vitiating the precision of the results is an excessive discrepancy between different broods of the same mating and generation. ‘The first step taken to overcome this difficulty was the system of testing nauplii in six different grades of poison solution rather than in only one. This device proved inadequate to overcome the trouble, and in the present year untreated controls were used. Each brood is divided into eight approximately equal parts. Six of these batches are tested in six strengths of sodium arsenite, as previously, and the other two batches are placed in medium without poison, but are otherwise treated alike. By this means variations from brood to brood in the natural death-rate during the testing period can be taken into account ; though at the expense of much more complicated calculations. It is clearly apparent from the results that the wide discrepancies between parallel broods mentioned above is not due to differences in natural death rate, but to variation in susceptibility to poison. An example of this, taken from the third selected generation of line C, is given in Table II (for the meaning of the letters designating sodium arsenite solutions strengths see Table III). Thus these controls are not sufficient to eliminate the excessive hetero- geneity, and other means must be sought to improve the precision of the experiment ; variation in temperature has been found to have no appreciable effect. In order to utilise the data made available on natural death an entirely new method of statistical reduction has had to be developed, which involves fitting three parameters to the data. The first is the slope of the probit regression line, i.e. the variability of susceptibility within a brood. This parameter is approximately constant for all broods of one line- 336 REPORTS ON THE STATE OF SCIENCE, ETC. generation. Thesecond is the 50 per cent. point, i.e. the strength of poison at which half the nauplii which have survived natural death, die by poison. The value of this parameter varies from brood to brood, its variation being the measure of heterogeneity among broods. The third parameter is the natural death-rate, which varies only slightly from brood to brood. As was said above, its evaluation does little to eliminate the heterogeneity between broods of the same line-generation. The introduction of this laborious method of statistical treatment has resulted in a considerable time lag between the actual experiments and the interpretation of results. ‘This makes it impossible, at the present time, to give a fuller discussion of the extensive data accumulated during the year. Efforts are being continued to discover the causes of heterogeneity, and to devise other improvements in experimental technique which will increase precision. The data obtained during 1937-38 are given in Tables [V—X. In Table III are given the strengths of sodium arsenite corresponding to the letters used in the other Tables. The Committee asks to be reappointed with a grant of £20. TABLE I. rae : | ~~ Line} C, | Cs er eee | OA ON ag UN Sab. oy Generation. ~~<"~ | | | S - +. «| 99) — | — | — | — |. 269 773 Sy en: . .| 870} 147) — = | = 2,562 3488 Seat : - | 158 |1,314 | 165 | — | — | 2,822 761 Daas é - | — |2,9063 | 609 | 280 | 116 | 1,761 —_— Ste z - | — | 2,402 | 1,741 | 28% hich 1,371 — Ss: . ‘3 — | 307 | 530} 407 | 374 ca: oa | | | | Totals. . raed (7,133 |3,045 | 968 490 | 8,785 | 5,022 | ! | | TaBLe II. Illustrating variation of susceptibility between broods of the same parents. Strength of : Control | Control Solution. H/} I J); K)L/M/N I 2, Brood 1: Tested . | — | 23 | 23 | 23 | 23 | 23 | 23 23 25 Surviving | — | 22 | 23 | 21 | 14/| 10 | 10 2I 23 Brood 2: Tested . | 14| 14 | 14| 14 | 14 | 14 | — 16 14 Surviving| 4| 2| 9] o| o| o/—/ 16 13 ARTEMIA SALINA 337 TasBLe III. Strength of Solution of Letter designating Sodium Arsenite, expressed Poison Solution. as Normality. E A 0*003715 F - 0*004102 G : 0*004529 H : 0*005000 I : ©*005520 J ; 0006095 K 3 0:006729 L i 0*007430 M 0-008203 N 0009057 O 0001000 TasB_eE I1V.—Line Co. So Si S. Tested. | Survived., Tested. | Survived.| Tested. | Survived. I 124 96 37 34 18 14 J 124 87 119 87 18 8 K 126 55 106 72 20 9 L 126 55 134 74 26 5 M 125 43 104 47 II ° N 116 4 124 16 25 ° O a == 65 3 — — Cont. 1 116 105 109 97 24. 20 Cont. 2 112 IoI 72 63 16 13 TaBLe V.—Line C3. S, Se S3 S, S; FE sc keadess,n Reale rs) T s Ab Ses elass G ax}1r} — | — |} — | — J — ] -—- I] ord H ar) ierah east) gor 6g): 33°| “3a: (Soi aes I 21 | 12 | 165 | r19 | 252 | 150 | 367 | 126 | 11 4 J 21 | 9 | 165 | 82 | 399 | 174 | 287 | 122 | 39 | 31 K 18 | o |. 165 | 82] 243 | 89 | 287| 89 | 39 | 23 L 37 | 4| 169 78 | 430| 97 | 267| 57 | 39 | 19 M — |— | 169 | 61 | 393 |. 49 | 209 43 | 39 | 13 N ro | a 9 | 458 | 39 | 2909/| 32/| 39] 8 O Sa |e 46 2° 30),|Pao Cont. 1 8 | 7 | 144 | 137 | 415 | 370 | 285 | 241 | 34 | 30 Cont. 2 — | — | 138 | 109 | 310 | 274 | 233 | 184 | 28 | 22 338 REPORTS ON THE STATE OF SCIENCE, ETC. TaBLe VI.—Line Cy. | Sa Ss S, S; | r ASR Ne Se ae S; FT i rer E —_ — | 23 22 —— _— _ — F — — 23 22 — —_— — — G 13 12 79 58 157 36 aay = H 27 18 100 68 167 67 44° 31 I 27 23 108 87 223 74 59 34 J 27 17 98 80 223 48 67 41 K 28 10 86 43 223 25 74, 35 L 28 3 81 39 261 33 74, | 33 M 15 2 II ° 45 ° 66 19 N = a rr ik 45 fe) 15 3 Cont. 1 — — = == 225 216 74, 66 Cont. 2 = = = — 152 141 68 57 TaBLeE VII.—Line C;,. Ss S, Ss Tt. S Alcs Ss. TR S. lr: 46 41 6 6 22 22 oe: 46 31 36 24 37 26 Kee 46 28 36 19 54 3I Tei 47 27 49 30 61 34 M. 47 18 50 23 60 25 IN: 48 8 51 2 54 2 (6 aed — — 18 ° 22 2 Cont. 1 = ss 21 21 64 62 Cont. 2 i a 14 12 33 33 TasB_e VIII.—Line C,. ar. S. ibe S. H 13 10 37 23 I 13 I 48 41 J 13 3 68 29 K 13 ° 68 22 L 17 2 68 14 M 17 I 66 2 N == = 19 ONO. Cont. 1 17 16 == — Cont. 2 13 8 = — ARTEMIA SALINA 339 TaB_e I[X.—Line Cy, x C. So Si Se ey |e Sue eel S ibe openianss hia koS F ee ee) |e 20 7a ae ee G ET AN |e 4 Lars) | POOR allt ase VIL H | = 4 | 193 | 48 | 204 | 137 | 126] 94/ 119 | 97 I 25 | 24 | 265 | 40] 402 | 99 | 222 | 134 | 199 | 159 a] 25 | 20 | 346 | 71 | 340 | 63 | 222 | 117 | 199 | 132 K cha i 16 | 311 34. | 347 | 28 | 221 80 | 199 | 115 L Si tgyy Eze logan o'g2) 3397) G2) azn | 57 i TQQT Oo 47 M ne) gi5 19 | 182 Selhar7 Be e285 O77 5 N 31 5 | 145 9) 45 °o | 95 peng 2 oO 10 ° 41 ° II ons ate Cont. 1 35 | 34 | 340 | 317 | 341 | 313 | 227 | 223 | 199 | 178 Cont. 2 34 | 32 | 284 | 268 | 343 | 306 | 192 | 174 | 178 | 149 TABLE X.—Line C, x C,. So S; S. Fe Ss: 1. S. EY Si G. 26 2 127 a7 II 5 H. 55 10 302 135 94 61 \ eC 82 20 406 145 94 61 Ts 102 31 440 93 94 47 KGr; 102 29 440 83 IOI 30 L 102 29 440 25 IOI 24 M. 76 15 318 8 83 19 ‘ele 47 9 143 ° ae = O . 20 ° —_ — — — Cont. 1 76 69 434 389 95 83 Cont. 2 85 82 438 375 88 77 340 REPORTS ON THE STATE OF SCIENCE, ETC. FRESHWATER BIOLOGICAL STATION, WINDERMERE. Report of the Committee appointed to aid competent investigators to carry out definite pieces of work at the Freshwater Biological Station, Wray Castle, Westmorland (Prof. F. E. Fritscu, F.R.S., Chairman ; Dr. E. B. WortuinctTon, Secretary; Prof. P. A. Buxton, Miss P. M. JENKIN, Dr. C. H. O’Donocuug, Dr. W. H. PEARSALL). DurING part of the current year the British Association’s table at the laboratory has been occupied by Mr. G. H. Wailes while working on the planktonic Protozoa of Windermere. Mr. Wailes, formerly of Vancouver, British Columbia, resided at Wray Castle in the autumn of 1937, and has since received and examined samples of plankton collected each fortnight by the Association’s staff. During the last part of the year Miss Pennington, of the Botanical Department, Reading University, has been appointed to occupy the table, in order to work on the succession of diatoms and pollen in cores raised from the bottom deposits of Windermere and other lakes. It is yet too early to report on Miss Pennington’s research, but Mr. Wailes has drawn up the following short account of his study. PLANKTON PROTOZOA OF WINDERMERE, During a visit to Wray Castle in September, 1937, collecting was carried out with the object of observing in a living state the planktonic species of Protozoa occurring in Windermere, as a preliminary to tracing throughout a complete year the seasonal changes that take place in the plankton in both the north and south basins of the lake. Commencing on September 22, fortnightly samples of preserved Windermere plankton have been received and have been examined. ‘They were obtained by hauling vertically a fine meshed net from a depth of 40 metres to the surface. As a result of the collecting done in September, chiefly in the north basin, the following species were observed which up to the present (June) have not been recorded in the serial plankton gatherings, namely the Heliozoans Acanthocystis spinifera and Raphidiophrys elegans, a small naked dinoflagellate Gymnodinium pulvisculus, which, like others of that group, disintegrates under the action of preservatives, and a small ciliate belonging to the Tintinnioidae which proved to be an undescribed species and has since been named Tintinnopsis wrayi (Ann. & Mag. Nat. Hist., May, 1938). The Protozoa present in the plankton during the period observed (September to June) comprise two groups; the first, consisting of the Dinoflagellata and Dinobryon divergens, was absent from mid-November to mid-February, whereas the other was persistent during the winter and consisted of species of Rotifera, Vorticella, and an infusorian, Mallomonas acarotdes. Dinoflagellata comprised the species Ceratium hirundinella var. gracile, Peridinium willet and Peridinium kincaidi (the last-named has previously been recorded only from Alaska and British Columbia). Numerous cysts of these species and individuals of P. kincaidi occurred until mid-November ; thereafter no dinoflagellates were observed again until mid-February. By March P. willei and P. kincaidi had become equally plentiful. Rotifera, represented by some seven or eight species, were numerous throughout the winter ; they have been submitted to a specialist for specific determination. The most notable feature of Windermere plankton was its different CYTOLOGY AND GENETICS 341 character at either end of the lake. In the north basin the quantity was comparatively small, and consisted for the most part of crustacea (Cladocera and Copepoda), whereas in the south basin the quantity was large, and consisted for the most part of phytoplankton throughout the period observed. This was due to the abundance of only a few species of Myxophyceae and Diatomaceae. This abnormally abundant production of phytoplankton in the south basin continued without diminution all through the winter, and is apparently due to drainage effluents from towns and villages discharging into this portion of the lake. A similarly large production of marine winter phyto- plankton occurs in the inlets on the west coast of Vancouver Island where fish reduction factories discharge their waste. In Windermere the zoo- plankton does not seem to be directly affected by this condition except in so far as the phytoplankton may afford a more abundant food supply ; but further study of the conditions obtaining on the two basins may have a pertinent bearing on the problems of water supply and the practicability of artificially increasing human food supplies. CYTOLOGY AND GENETICS. Report of Co-ordinating Committee for Cytology and Genetics (Prof. Dame _ Heten Gwynne-Vaucuan, G.B.E., Chairman; Dr. D. G. CATCHE- SIDE, Secretary; Prof. F. T. Brooks, F.R.S., Prof. F. A. E. Crew, Dr. C. D. DarwincTon, Prof. R. A. FISHER, F.R.S., Mr. E. B. Forp, Prof. R. R. Gates, F.R.S., Dr. C. Gorpon, Dr. J. Hammonp, Dr. J. S. Huxiey, F.R.S., Dr. T. J. Jenxrn, Mr. W. J.-C. LAwReENcE, Dr. F. W. Sansome, Dr. W. B. Turritt, Dr. C. H. WADDINGTON, Dr. D. Wrincz). THE Committee have continued to assist and advise Organising Committees and Recorders in arranging for joint sessions and other means for promoting closer co-operation between cytology and genetics and other fields of biology. It was thought that the bearing of recent cytological and genetical dis- coveries on other aspects of the old problem of the Mechanism of Evolution was imperfectly understood by many biologists. The Organising Com- mittees of Sections D and K were approached with the suggestion that a joint symposium occupying a morning and afternoon session should be devoted to this subject. The proposal was approved, and a number of papers dealing with various phases of the problem have been arranged. The Organising Committee of Section M were unable to find space in their programme for a discussion of Genetics in Relation to Agriculture. However, they sought the Committee’s advice in arranging for genetical contributions to their symposia on Crop and Stock problems respectively. The Committee have also felt that a useful service would be rendered to workers in other biological fields by the presentation of demonstrations. They have organised an exhibition illustrating the principles of the Genetics of Colour in Animals and Plants, demonstrating wherever possible the chemistry of the pigments and colour differences concerned. A descriptive brochure is in course of preparation. 342 REPORTS ON THE STATE OF SCIENCE, ETC. MINING SITES IN WALES. Report of the Committee appointed to investigate early mining sites in Wales (Mr. H. J. E. Peake, Chairman; Mr. OLtver Daviess, Secretary ; Prof. V. GorDON CHILDE, Dr. C. H. Descn, F.R.S., Mr. E. Estyn Evans, Prof. H. J. FLeure, F.R.S., Prof. C. DaryLL Forbes, Sir Cyrit Fox, Dr. WILLOUGHBY GARDNER, Dr. F. J. Nort, Mr. V. E. NasH WILLIAMS). THIS spring a survey and excavation of the ancient mining-dumps at Great Orme’s Head, Llandudno, was carried out on behalf of the Committee. Stone hammers, of the type believed to be approximately Roman in date, and cup-marked querns had previously been found there. ‘The examina- tion, however, showed that they occurred in no orderly sequence, and some were found on parts of the dumps which can hardly be more than a century and a half old ; it is therefore probable that they have been thrown out of ancient workings by recent miners. Patient search may yet reveal the ancient dumps not too deeply buried by modern detritus. It will be particularly unfortunate if more copious evidence of the ancient workings is not discovered, as this must have been one of the most important ancient mines in Wales. A few hours were also spent testing a habitation site below Great Orme’s Head, near the Gogarth Hotel, which it was believed might be a mining settlement. The site yielded a considerable depth of stratification arid some pottery, which has not yet been examined. No evidence was found for its association with the mines, so it will not further interest this Com- mittee. Thanks are particularly due to Mr. G. A. Humphreys, on behalf of the Mostyn Estates, for permission to excavate and for help in many small ways, and to the Ecclesiastical Commissioners for permission to dig on their lands. The following specimens have been examined : By Dr. C. Desch, at the National Physical Laboratory: copper bun- ingot, Penmaenmawr, sent by Mr. W. J. Hemp; contained 1:0 % lead, traces of iron and nickel, but no other metals. At Queen’s University, Belfast : (a) Heavy compact slag with few gas-holes ; colour, black with reddish stains; from Forden Camp, Montgomeryshire (Roman), supplied by Welshpool Museum. Contains 52:21 % iron, no copper, lead or zinc. An iron slag, probably derived from smelting and not from a smithy. (6) Specimen of quartz, containing chalcopyrite and some galena, found in the Roman fort at Caersws and supplied by Welshpool Museum. Con- tains 25:45 % copper, 28:8 % iron, some sulphur, no lead, silver, anti- mony, arsenic, bismuth, zinc, nickel or cobalt. Apparently there happened to be no galena in the fragment analysed. (c) Bornite, slightly magnetic and containing specks of native copper, from the Roman fort at Caersws, and supplied by Welshpool Museum. Contains 15:47 % copper, 11:69 % iron, 6:49 % sulphur, 0:02 % lead, no silver, antimony, arsenic, zinc, cobalt or nickel. These last two specimens had presumably been collected in ancient times from one of the Montgomeryshire mines. ‘They indicate the working of. some of these mines under the Romans, and show that the road through central Wales, though primarily military, had also some economic signifi- cance. ‘They afford confirmation of a fact pointed out in a previous report, MINING SITES IN WALES 343 that though lead is the predominant metal in the mineralised area of Plynlimon, the most ancient mines, marked by stone hammers, exist at occurrences of copper-ore. i (d) Fairly light and crumbly ferruginous slag, found with a small piece of metallic lead, Newtown mine (Montgomeryshire). Contains 53°22 % iron, 4°2 % zinc, no lead, arsenic, antimony or copper. ; (e) Galena and pyrites disseminated in quartz, Newtown. Contains 12:08 % lead, 7°89 % iron, 2:3 % copper, no silver, bismuth or zinc. This mine was examined in 1937, and it is hoped shortly to publish a report in the Montgomeryshire Collections. (f)-(k) Specimens from Dinorben hill-fort, supplied by Dr. Willoughby Gardner. ; _(f) 1134, copper bun-ingot, yellow and very malleable ; metallic, with a little malachite on the surface. Contains 96:72 % copper, very slight traces of lead and tin, no antimony, arsenic, silver, iron, zinc, bismuth, nickel or cobalt. (g) 1331, iron slag, black, friable and full of gas-holes, resembling a smithy-slag. Contains 57-61% iron and no copper. (A) 1316, black iron slag with some gas-holes. Contains 52:66 % iron, traces of copper. (z) 584, whitish-grey material of amorphous structure, containing 1:02 % lead, 0-93 % tin, no silver, much insoluble material. Probably earth which has been in contact with one of the numerous tin-lead alloys of Roman date. (j) 1157, ferruginous material, with almost no insoluble residue. Con- tains 79°21 % iron and no copper. Probably rusted iron. (k) Hard and well-fused slag, from the surface. Contains 52:9 % iron, no lead or copper. (1) Heavy black slag, Talargoch, a mine believed to be Roman. The slag is crystalline in structure and without gas-holes, owing to slow cooling. It contains 40-4 % iron, 0:24 % lead, 2:14 % zinc, no copper. DERBYSHIRE CAVES. Sixteenth Interim Report of the Committee appointed to co-operate with a Committee of the Royal Anthropological Institute in the exploration of Caves in the Derbyshire District (Mr. M. C. Burkitt, Chairman ; Mr. A. LesLiz ARMSTRONG, Secretary ; Prof. H. J. FLeure, F.R.S., Miss D. A. E. Garrop, Dr. J. WILFRED JACKSON, Prof. L. S. PALMER, Mr. H. J. E. Peake). Creswell Crags——Mr. Leslie Armstrong, F.S.A., reports as follows : “The Yew Tree Shelter —Excavations were continued on this site during the early autumn of 1937 and yielded further evidence of occupation contemporary with that of the Lower Middle and Middle zones of Mother Grundy’s Parlour and proved this to be the principal period of its occupa- tion during late Palzolithic times. “ A scatter of microlithic flakes and implements on the top of the deposit indicates casual occupation, comparable with that of the final occupation of Mother Grundy’s Parlour, of Azilio-Tardenoisian facies. 344 REPORTS ON THE STATE OF SCIENCE, ETC. ‘ Woolly Rhinoceros and Wolf were added to the list of fauna previously recorded for this site. ‘ Half a perforated axe-hammer, of hard sandstone, was found in the surface soil, but was unaccompanied by any evidence to establish its date. ‘ Boat House Cave.—Since submitting the 1937 report, little progress has been made here, owing to a transference of activities to Whaley, due to the location of a further rock shelter there and the opportunity which arose for its immediate excavation. ‘Work is now proceeding on the removal of the concrete which covers the cave earth in the Boat House Cave, and it is anticipated that this will be completed by the end of July over an area sufficient to permit excavation of the underlying cave deposits during the autumn and winter. ‘Whaley Rock Shelter, No. 2.—This was located by Dr. Arthur Court, in August last, by trial sections which he dug on what appeared to be a most unpromising site. ‘This consists of a talus of limestone rubble and rocks which, on removal, proved to completely mask a cliff at the rear, and appears to have resulted from the collapse of a former over-hang of the cliff which had provided a rock shelter during Pleistocene times. “Above the cliff is a small plateau of limestone, sheltered by a rocky slope at the rear, which has apparently been favoured as a camping ground from Neolithic to Roman times. The successive occupiers of the plateau have thrown their camp debris over the adjoining cliff and this material is now found stratified in the talus. ‘A systematic excavation was commenced here in September and is still progressing. The talus has been removed over a length of 20 ft., in successive layers, down to the Pleistocene horizon and the hidden face of the cliff exposed to a height of 12 ft. Except for a trial section, the Pleisto- cene deposit has not yet been excavated. The trial section has established the presence of Upper Paleolithic artifacts, in association with remains of Reindeer and Hyena in this level, and its excavation will now be proceeded with. ‘'The talus has yielded Neolithic pottery of Peterborough type; also pottery of Bronze Age; Bronze-Iron Age overlap period; Iron Age; Roman and Romano-British wares ; also artifacts of flint and bone, pot- boilers and animal bones in great abundance and a few human bones, including portions of three mandibles. ‘ An exhibition of the whole of the artifacts and a selection of animal remains, obtained in the Pin Hole Cave, was displayed in the Manchester Museum from November 1937 to April 1938, and thanks are extended to Mr. R. U. Sayce, M.A., Keeper of the Museum, for providing the facilities and arranging this exhibition. These exhibits were also included in the exhibition of recent archeological work at the Institute of Archzology, Regent’s Park, London. “A further grant of £25 is earnestly requested by the Committee for the continuation of the work at Creswell Crags and Whaley.’ BLOOD GROUPS 345 BLOOD GROUPS. Report of the Committee appointed to investigate blood groups among primitive peoples (Prof. H. J. FLeure, F.R.S., Chairman ; Prof. R. R. Gates, F.R.S., Secretary; Dr. F. W. Lams, Dr. G. M. Morant). Durinc the past year blood group testing has been going forward in certain areas, of which a preliminary report was made last year. Opportunity was taken by Prof. R. R. Gates, F.R.S., after the meeting of the Indian Science Congress Association in Calcutta, to visit various centres in Southern India, and arrangements have now been made through the official channels for blood grouping various native tribes, particularly in the States of Mysore and Travancore, where numerous different types exist. Further work in Assam has been in abeyance, but is now being taken up again, and results are also expected from other parts of India. A further development begun this year is the testing of local groups of population more or less isolated in different parts of the British Isles, in conjunction with anthropometric studies of the same people. Dr. M. A. MacConaill visited Rachrai Island, on the north coast of Ireland, and blood tests of those available were made. The population appears to show peculiarities in blood groups as well as in other anthropological characters. It is hoped to extend this work to various other population groups which have remained more or less isolated. A survey of such groups will show the effects of local isolation, and will also indicate whether, in such popula- tions, any statistical correlation exists between blood groups and other anthropological or racial characters. SUMERIAN COPPER. Eighth Report of the Committee appointed to report on the probable sources of the supply of Copper used by the Sumerians (Mr. H. J. E. PEAKE, Chair- man; Dr.C.H. Descu, F.R.S., Secretary ; Mr. H. Batrour, F.R.S., Mr. L. H. DupLey Buxton, Prof. V. Gorpon CuHILpE, Mr. O. Davies, Prof. H. J. FLeure, F.R.S., Dr. A. Ratstrick, Dr. R. H. RASTALL). TuE last report was presented in 1936. Since then the work has been continued without a grant, and this has occasioned some delay. Some analyses were reported to the Committee at the Nottingham meeting in 1937, but were not published. The analytical work has been by no means confined to objects of Sumerian age, but many archzologists have taken advantage of the facilities provided to submit specimens of ancient metal. There is undoubtedly a demand for a permanent centre, with a staff accustomed to the analysis of such metals and familiar with the characteristics of ores from various regions. By the use of microchemical methods it is possible to make a complete analysis on 10 miligrammes of metal, so that the natural objection of museum curators to allow drillings to be taken from valuable objects is obviated, as a cavity left by drilling such a quantity is almost imperceptible. Such analyses are comparable in accuracy with those on larger quantities, owing to the special technique employed. The 346 REPORTS ON THE STATE OF SCIENCE, ETC. work is at present carried out in the Metallurgical Department of the National Physical Laboratory, under the direction of the Secretary. The total amount paid to the Department of Scientific and Industrial Research since the 1936 Report is £94 17s. 10d. ‘Towards this contributions were received of £10 from the Copper Development Association and of {10 from Miss Winifred Lamb. A generous gift of £100 from Sir Robert Mond has now enabled this cost to be covered. The analyses made have included a series of fourteen copper specimens from the Anatolian site of Kusura, submitted by Miss Lamb. The results are published in Archeologia, 1937, (ii) 86, 1-64. ‘Two contained tin, in quantities of 2°8 and 1°2% respectively, a few having much smaller quantities. The specimens from period A, however, contained arsenic in appreciable quantities, up to 0°59%, whilst the specimens from the later periods contained no more than traces of that element. Lead was present in only one specimen: that containing the larger quantity of tin. Three iron objects were found in the highest levels. Some copper objects found by Mr. Mackay at Chanha-Daro proved to be free from tin, and to contain only minute quantities of arsenic and nickel, but some of them contained sulphur. Ancient slags, collected in Persia towards Baluchistan by Dr. J. V. Harrison, were examined, but none of them could be identified as being derived from copper-smelting operations. An interesting series of Central Asian bronzes, including several of the Minussinsk type, was submitted by Miss V. C. C. Collum. A preliminary description of them has been published in the Fournal of the Royal Central Asian Society, 1938, 25, 22-23. These were of varying composition, several being notable for their high content of lead. Miss Collum also supplied a series of bronze axes from Brittany, the analyses of which will be published shortly. The excavations which she had carried out for Sir Robert Mond in Guernsey have also led to an investigation of early iron objects, and several iron hammers of known Roman age have been obtained from museums and examined microscopically. A good deal of information about the structure of bloomery iron has now been collected. A very extensive series of copper and bronze fragments from Troy I-IX, submitted by Prof. Blegen, is in course of examination. The series will be most conveniently reported on when complete. It is, however, interesting to note the marked differences between the chemical composition of objects from the earlier and the later levels. Several specimens of electrum found by Sir Flinders Petrie at Tell Ajjul in Palestine were also analysed. The Secretary has been in correspondence with a number of archeologists in other countries, who are now carrying out analyses of copper and bronze from a great variety of sites, so that an extensive mass of material is being accumulated. There are, however, many sites from which objects have been described as copper or bronze from their general appearance only, and detailed analyses are very desirable. There is an advantage in keeping the Committee in being, although with a more general title, as a centre for such information. KENT’S CAVERN, TORQUAY 347 KENT’S CAVERN, TORQUAY. Report of Committee appointed to co-operate with the Torquay Natural History Society in investigating Kent’s Cavern (Sir A. Keitu, F.R.S., Chairman; Prof. J. L. Myres, O.B.E., F.B.A., Secretary; Mr. M. C. Burkitt, Miss D. A. E. Garrop, Mr. A. D. LacalILue). Tue following report has been received from the excavators :— Work was recommenced on October 25, 1937, and continued until March 28, 1938, when, having excavated to a depth of 34 ft. below the datum line (the lowest point ever yet reached in the exploration of the Cavern), it appeared as though, through a distinct falling off in the number of finds, it would not be sufficiently profitable to go deeper considering the difficulty of working between rocks, and the time involved in getting the material brought to the surface. It was decided to close for the season, and next year to make a drive from the ‘ Vestibule ’ to the ‘ Sloping Chamber.’ Flints have been very scarce, nothing worth recording having been found, but fortunately several good bones and teeth were secured, in- cluding an ante-penultimate milk molar of a mammoth in fine condition, a large specimen of the base of a rhinoceros horn, two vertebre of a salmon, which is quite new to Kent’s Cavern, the humerus and furculum of a bird similar to a mallard ; but the most striking finds were a meta- tarsal bone of a bison with two each of the first and second phalanges, all of which articulate perfectly, which, so far as is known, is the first instance of more than three bones being found together capable of arti- culation ; teeth of horse, hyena, deer, rhinoceros, Irish deer, bear, and bison were also fairly numerous ; coprolites were scarce. ArtTHuR H. Ocitviz. B.N. TEsss. The Committee applies for re-appointment, with a further grant of £5 toward the cost of unskilled labour to assist the voluntary excavators. TRANSPLANT EXPERIMENTS. Report of Committee on Transplant Experiments (Sir ARTHUR HILL, K.C.M.G., F.R.S., Chairman; Dr. W. B. TurriLi, Secretary ; Prof. F. W. Otiver, F.R.S., Prof. E. J. Satissury, F.R.S., Prof. A. G. TANSLEY, F.R.S.). . THE experiments are being continued at Potterne, Wiltshire, along the lines suggested by the Committee. Meetings have been held at Kew and at Potterne. A fifth biennial report has been accepted for publication in the Yournal of Ecology, and a summary of results for the first ten years of the experiments has also been prepared and is to be published in the same periodical. A grant of £5 was made at the Nottingham Meeting. Most of this has 348 REPORTS ON THE STATE OF SCIENCE, ETC. been spent on the repairing of instruments and on labour. It is requested that the remainder, if any by the time of the Cambridge Meeting, be allocated for use in the latter part of this year (1938) and that the Committee be kept in being. A full financial statement will be available by the time of the Cambridge Meeting. INFORMATIVE CONTENT OF EDUCATION. Report of the Committee appointed to consider and report on the gaps in the informative content of education, with special reference to the curricula of schools (Sir RicHarD GrecorY, F.R.S., Chairman; Mr. G. D. DUNKERLEY, Vice-Chairman; Mr. A. E. HEnsHati, Secretary ; Prof. C. W. ATTLEE, Miss L. Hicson, Mr. H. G. Wetts, Mr. A. Gray JONES). INTRODUCTION. AT the Nottingham Meeting of the British Association for the Advancement of Science, Mr. H. G. Wells, in his Presidential Address to Section L, took as his subject ‘ The Informative Content of Education,’ and outlined what he considered should be a minimum curriculum for all pupils. Consequent upon what was then said, this Committee was appointed ‘ To consider and report on the gaps in the informative content of education, with special reference to the curricula of schools.’ The Committee had therefore to investigate in what way the actual work of the schools con- formed with the minimum curriculum proposed by Mr. Wells. An Analysis of Mr. Wells’s Proposals. The first step taken was to prepare an analysis of the curriculum suggested by Mr. Wells. For this purpose both his address and its illustrative chart Were examined and an attempt was made to relate the proposals to the actual conditions of school organisation. It will be recalled that Mr. Wells divided his curriculum into Grades, of which A, B and C gave what he regarded as the absolute minimum for all pupils, although he added Grades D,E and F. It was with the first three, therefore, that this Committee was primarily concerned. Fortunately Mr. Wells indicated the time which in his view should be given each week to this aspect of school work and also the total number of hours to be allocated to each grade. From these facts it became obvious that the information included in Grade A was intended for pupils between the ages of 5 and 7, that in Grade B for pupils of the ages 7 to 11, and Grade C for those aged 11 to 14 plus. The grades thus corresponded roughly to the divisions of the English elementary school system, viz. Infants, Juniors and Seniors. : The examination of the speech and chart, therefore, enabled the following analysis to be prepared and the sections to be taken in infants’, junior and senior schools to be indicated. 349 INFORMATIVE CONTENT OF EDUCATION ‘aAT] SeuTue pue sjue[d MOF{ “sTeUIUe 0} UOT}BIAI UT syUeTq ‘aat] Ady MOY pur sjeurTUL ynoge sjowq ‘“sjsvaq pue spiIq IOF pooj pue sowoy ‘ssovjd Surpry se sjueyg | *sommjeoro oneyjeduiAs 0}UT jeliayeur orewyysru wos ‘ade ‘1981} ‘Jom ‘1e9q 94} UIN} YSTUL 9M YUrIYI JT "aqo]s SB P[IOM ‘Aydeis003 jo siseq AydersodAy [eo0'T I9YILVI MA sod pny *sulzoo1j ‘uorerodeAa : pros ‘sed ‘pmbrj—101V A, ‘AydeasorsAhyd jo siseq | “suryioq *spur] 19430 UI 9sOy} puke saTInj}Uue. IawWIIOJ JO VSOy} YIM IAT] UsIpPTTYyS yoryM JepuN suoipuocs surjse1ju0D *spur] Joyj0 pue ysed ay} JO sor10ys 9nI} Surjja3 Aq urldeq 9M ‘AydeisorsAyd Arvjuswi]q *19}}eUI Jo UuOTyISOduI0, | *19}}8UI JO Ssa}e1C | *OIVJIE AA | ‘ajdood Arojepoig *€ | "sdryg | *yiodsuei J, ‘Opel, *Z | *sjeuuruy JO UOT}eOT]sOUIOG | sulpnpour ‘eimjnosy “1 : suoedno99 “SUI OTS ‘syny ‘siajJoys ‘saavo—souIoy sATIUWIIG *suodeam ‘s[oo}—2j1] 9dBABG *9UUT} UT yuowidoysasp i194} pue soin3jno uewiny ynoqe seepr AseyUaWIETy *‘mnoy I “OOM jad ‘utur Sz ‘siy z "yooM Yyoro ‘ulur Sz ‘sy Z : 9uIT} JO o1/F ‘ - sjeunuy pue sjuv[g jo Asojors -Ayg Areyuowely ; Auejog pue Ago[00Z eandrioseq ABOlOIg . * Aydeis0a5 * Jaye JO saqeVI1G A1IOISTFT *qoveds ut 10M Jo adoos *yreyD UT yIOM Jo adoos | | | *paMmoyye Wty *sanoy oob—oof °L-S sad “yy Advuy *yoafqns REPORTS ON THE STATE OF SCIENCE, ETC. 35° *zang pue au0oYy ‘YIOX MIN ‘ony ‘uopuo'y *3°q ‘ale SoIyId uMOUy-]Jem seov[d jo puny 2943 pue uorsod oY} oy uOoseeI oy} ‘uotsod oy} Mouy 0} sjidnd ajqeua 0} Aydeisodo} jo aspaymouyy *suOIdaI 9S9Y} JO YORI UT PaAT] IF] URLUINY FO 410G *pjiom 9y} JO SUOIder UleUL oy} jo seuney pue seIOY 9ATOUTISIG *Aryunod Jo adj Jo seapt astoorg “yy[eeM pue JaMod jo 901nos B sB pue jeiIqey ueUMYy Be se plIoM 94} Jo AdAIns [¥Ioues WY ‘seunesz pue seioy pue Aunoo jo sadfy, ‘sulpeol-dew 9]}u] VW “ASoj0a5) pue Aydeis0e5) : Inoy I * fydeiZ005 ‘20uRI,y pue Ule WIG yeoIgy Jo Arzoystpy AreyUOWETy ‘AyuRTsIIyD JO YIMOID pur osny *$29}81G USIBIVAOG UIOpoyy “WIRIS] JO YZMOID pur asry | JO vouvIeedde sy} pue wopus} ‘sojdoad Sunyeods-uedry jo Sururod | -slyD yo dn-yee1q Jo vapt [erauer) “AyruRNsty) URUOY *UIBIS]T soiiduiq ; ueTuopaoryj[ *BOlIOUIY | uvIsiog JO JUSUIYsST|qeisq *euly ‘sojdoed Suryveds-o1j1Wieg FO ashy *IULOY, *surddrys jo yuauidojaaap ‘speor jo ‘aseyqied) uoljonIjsu0s ‘asioy 24} JO UOT}ONpoOI{UyT "909915 ‘uot ‘1addoo ‘auo}s fo UOIss999NG *BISIOg *IOLIIVM ‘IOUILF : jo AIO\sTY UI BOULOYTUSIS [eIaUE+) ‘gury ‘ysorid jo sajgi sutdojaaep 2eY,J, *SuUOT}eSTTIAIO AjIey ‘uorjest[IAro Areuutid JO YIMOID) “UBUL JO SOB YY ‘ulul Sz -siy Zz “UOTJeSTIAIO A[IVa JO £103G *AIOISIFY [esas :*sIy Qg jo o1/¥ : AIOISIFT “yaeqo “OunTy, *yoofqns *yoveds *sAnoy Ooo‘ ‘1I-L sasp "gq aAdvay ae 351 INFORMATIVE CONTENT OF EDUCATION “IBM JO AIOISIFT “UISTUNUTUIOD ‘9383s 93¥I10d -109 ‘UISI[BENPIAIPUI JO SaTIo0ay} Surpea’y *Ayei] pue Aueursoy jo uonvoyiup *I9MOg YoING JO [ej pue ssny *IaMog ystuedsg jo [ej pue osny ‘oreg jo AroIsIpT “BISSMY JO IsIy “aridwiq ULUI0}IG JO ][eF pue ossny : SB BustUOUsYd Yons Jo Apnis ‘u01}deIIp orm10U -099 JuajaduI0d OJ YoIvss 94} pue Axojstf{ UI sasueyo oruIOU -099 JO 90uRr}IOdUIT SuIseaIOUr 9Y,T, *saliepunog [erieduit pue jeuoneu suljstxa Jo Jusudo[sAsq *AIOoY,T, [BON]Og Ul s}usWIETA "yoo jad ‘sy %z ‘1va0A Jad oor “sik + ul ooF ‘a'r ‘atuT} gjquyreae jo o1/+ AIOISTFT *yoveds "y7eq9 ‘ou, *yoalqng *SANOY OOO I *+41I-11 ssp ‘DQ Tavay *sjusplooY pue sjusWIa[qQsojuq “SaSBaSIp Joly “uoljonpoiday *saIpoq Ino JO SUTAIONM *soul] UJOpour sour uodn Ast -wieyo pue sorsAyd oimd jo uonepunoy *pulyueUul JO 9duasIOWIE [enpeis pue P]toM 9y4} UI UBUI-qns Jo sDUasIOUIY ‘suluUIseq 94} WOIt aI] jo A10IG *soroods Jo JuaUIs0R[da1 pue UOT}OUT} xO ‘guipep ‘Aqyt1edsoid 94} ur sessad0i1d oy, J, *9UIT} UI SSUIY} SUTAT] JO UOISSaD9NG ‘Asojoujed Arejuswe ‘uononpoider jueid pue [ewrue jO svopl ]eioues ‘1va]9 SuUIpNpUyT “Auojyeuy pue AsojorsAyg *AIOAOOSIP pus uoljusAur jo Aro\sty AreiUsWOETA ‘ramod pure wistueyosyy *19}}e8UI jo sjdsou09 uropow oj dn surpea’T “AIjstusyD pue sorsAyg ‘uOINJOAS puke AsojOos ynoqe SvopI [eIousy ‘Sede [BOIsOTOI5) *9UIT} UI UOTS -so00ns II9y} puke SUTIOF 40UT}xa Suipnpur ‘Auejog pue Asojoo7 + Asojorskyg (2) | ‘193 BJA] oye UWUTUe -uy Jo aousI9g (4) ; * ABojorg (2) *20U9T9G 352 REPORTS ON THE STATE OF SCIENCE, ETC. *‘4ajgUl & JO VDIOYD 0} UOT}UA}e yoelIp 0} sodA} [eos YIM pozeIo -osse 9injonijs [eos Jo Apnjs [e1oues *pjIom 943 jo suonejeidieyur jeorydosoyryd pue SnoIsier Joryo Jo suonmtsodoid Aseu1rg ‘9SIOATUL) 9} 03 Jjeseuo Jo UOT}e[9I 94} JO seapr [eIoUey ‘uoTJeYep puke uONeyUr Jo souULOyIUSIG ‘S][TUIPUTA [eIISNpur , qooye AguoUr JO suoTjeNjoNy YoryM ut Aem oy, “yuowAoj;duia pue sasem 0}UI WOpyies pue AIsAR]S pasueyo sey Asguowr yorum ut AeA ‘AuOUT pue Aysodoid Jo suomusAuo0d Jo aspayMouyT ‘O90 S190]eM ‘jor30d ‘jeoo ‘saoImo0s -o1 ][eInjwU JO UOT|sneyxo pue 91SEM ‘uo1lyvAnNo piezeydey Yysno1y} s}1esep pues Aq o1njsed Jo JuswI99R[der‘s}sa10jF S,Pp]0M JO uoNEIseAVq ‘9qOTs 94} Jo sa0Inosei pedoysAspun pure podojaasp oy} puke pjIoM 943 ur uoNefndod jo sodA} JusrayIp yim ‘Aydeisoes pjiom Yat souvjurenboe jor1dxe pue peyiejoq *2]O1 JO voIoYyo 0} SurIpesy sodA} [eros jo Apnig ‘UOISI[aI SAIWBIedwIO0Z "sap! [eiouas Jo AIO}sIYy 410YS VY ‘aJI] OTUOU0D9 ur Asuour pue Aj19do1d jo 9]QI 9, ‘ainjoejnuewl pue uoonp -oid ul suoneaouuy jo AiojsITT V ‘ope1y, pue suonvorunuu0d jo Aro\sIy 4104S BENE IB A A8ojo9y pue Aydeisoay o1rm0u00q ASO[OINOG [euosieg * wWISTUBYSaTAT [BIN0G : * Aydeisoay *qoveds "yaeq9 *‘panuyjuogI—*) AAVAL) ‘ou, “yoafqns INFORMATIVE CONTENT OF EDUCATION 353 The Schools and Mr. Wells’s Suggested Curriculum. The next step was to discover how far the work already taken in the schools coincides with, or falls short of, that included in Mr. Wells’s suggested minimum curriculum, and if possible, the reasons for any differ- ences that might be revealed. Accordingly, the following questions were prepared : ; (1) What part (or parts) of the suggested Informative Content of Educa- tion for children aged are now taken in your school ? (2) Of the remainder, what part (or parts) do you think (a) might be advantageously included in the curriculum ? (b) should not be included ? (3) What obstacles prevent the inclusion in your curriculum of the sections given under (a) above ? (4) Why would you exclude the sections given under (b) above ? (5) What textbooks (if any) have you found of assistance in reference to the sections you include ? (Please give the textbook which has been found of assistance for each section.) Elementary and Preparatory Schools. Copies of both the analysis and the questionnaire were then submitted to a number of head teachers in elementary schools in various parts of the country and they were asked to furnish replies to the questions based upon the actual work taken in their own schools. The following table gives the particulars as to the distribution of the questionnaire and the schools from which replies were received. Kind of Number to Number of replies Towns where schools are School. whom sent. received. situated. Infants’ . 6 3 Birmingham, Rhondda, Sunderland. 3 head mistresses | London, Nottingham, Junior ‘ 9 7 Ealing. 4 head masters Kesteven, Cambridge, London, Cannock. Santor ~ . iT gf 3 head mistresses | Hull, Stafford, Bristol. | 5 head masters Oxfordshire, Darlington, Torquay, Lowestoft. In addition the questionnaire was submitted to the head masters of six preparatory schools or preparatory departments of secondary schools, but only three replies were received and of these one did not supply any information. Secondary Schools. Later the inquiry was extended to secondary schools, and for this purpose the following amended form of questionnaire was used : (1) (a2) What part (or parts) of the suggested informative content of education for children aged 11 to 14 years are taken in your school for pupils between 11 and 14? N 354 REPORTS ON THE STATE OF SCIENCE, ETC. (6) What part (if any) not so included is taken with pupils between the ages of 14 and 16? (2) Of the parts not included, what part (or parts) do you think (a) might be advantageously included in the curriculum for pupils between 11 and 14? (5) might be advantageously included in the curriculum for pupils between 14 and 16? (c) should not be included in the curriculum ? (3) What obstacles prevent the inclusion in your curriculum of the section or sections given under (2a) above ? (4) What obstacles prevent the inclusion in your curriculum of the section or sections given under (2b) above ? (5) Why would you exclude the section, or sections, given under (2c) above ? (6) What textbooks, if any, have you found of assistance in reference to the sections you include in your curriculum ? (Please give the textbook which has been found of assistance for each section.) This revised form, together with the detailed analysis of the curriculum proposed by Mr. Wells, was sent to twenty-one secondary schools, including Rugby, Shrewsbury, and Liverpool Collegiate School; but replies were received from only four boys’ schools and five girls’ schools. Of these one supplied practically no information. THE CURRICULUM IN THE ELEMENTARY SCHOOLS, (1) Replies from Infants’ Schools to Questions on Grade A. The replies revealed a fundamental difference between the method of approach used in the schools and that upon which the inquiry was based. The inquiry had reference to the factual information pupils were expected to acquire ; but the approach commonly adopted in infants’ schools is not by way of definite instruction ; the imparting of knowledge is not regarded as of primary importance, and the division of what is taken into subjects is no longer practised. ‘ Subjects,’ wrote the head mistress of a Sunderland infants’ school, ‘ as set out under separate headings, have largely disappeared from the modern infants’ school and given place to activities and experiences in a prepared environment.’ ‘ There is a fundamental difference of opinion in regard to the treatment of children aged five to seven’ was the reply of a Birmingham head mistress. ‘I feel that children should be provided with opportunities for actual experiences ; any knowledge in the form of facts will be gained through their project work and will be incidental.’ This fundamental difference in the way infants’ schools are regarded is of primary importance in this inquiry and must be borne in mind when the replies are under consideration. Little attention is given to History as such in these schools. It is not taken as a subject, though ‘ much incidental knowledge of people of other lands and primitive people is gained from Bible stories, fairy stories, fables and myths.’ Likewise the information included under the heading of Geography is given only incidentally. In the Rhondda, the basis for information was said to be such simple aspects as ‘ name of home, street, school and town.’ In the Sunderland school the instruction in this subject is based upon the teaching of local topography, following on school visits to such places as the seaside and the farm, and conversations about the district. INFORMATIVE CONTENT OF EDUCATION 355 The suggested Biology is not taken in the Birmingham school, though the head mistress thinks that a little of it might be, ‘to remove the “ nightmare ” reaction.’ Stories of wild animals are told in the Rhondda school, and in Sunderland the head mistress reported that the information is given in the stories of animals connected with such projects as the farm, the circus and the Zoo. In the same way the Descriptive Zoology and Botany are taught in the last-named school, through the care and observation of animals and plants kept at the school. Daily nature and seasonal news of animals, birds, etc., and the daily observations on plants in the various seasons, are a feature of the Rhondda school, and reference was made in the reply to a Nature Table. No reference was made in any of these replies to a school garden, which is known to be a feature of some infants’ schools and which would enable much of the informative content included in this section of Mr. Wells’s proposed curriculum to be adequately taught. There was an indirect reference to it, however, in answer to the question relative to the obstacles in the way of teaching what is considered desirable. ‘School buildings,’ it was said, ‘need to be replanned to give more space for free movement and experimental work for the children. Classrooms should look out to gardens for nature study and care of animals.’ The replies to the question as to the part or parts of the scheme that should be excluded were: (1) From Birmingham : ‘ Any subject matter which is beyond the power of the normal child to assimilate. Children under seven cannot appreciate differences in time.’ (2) From Rhondda: ‘ Detailed study of Geography, Biology, Botany, human cultures and development should be left to later stages of school life. Plants, animals, weather conditions, are dealt with incidentally in ‘daily talks.’ (3) From Sunderland : ‘ History.’ The reasons given for these exclusions were : (1) ‘ Fundamental difference of opinion in regard to treatment of children aged five to seven. I feel that children should be provided with opportuni- ties for actual experiences. Any knowledge in the form of facts will be gained through their project work and will be very incidental. Definite lessons on the animals would not be included. After seven the child is ready for much of this formal teaching. Before seven some children gain much factual knowledge through their reading and their experiences, but there can be no uniformity if the children have progressed freely and individually. I feel that here our great task is social training, and I am putting formal teaching later and later.’ (2) ‘The children’s interest in the people and things in the world immediately around them, with its attendant vocabulary, should first be aroused and satisfied. Analysis of these conditions, and their origin and development, are dealt with in later school life. The two-year course in the infant school does not allow time for detailed study of Botany and Biology, nor does the children’s ability permit it.’ (3) ‘ The children in this school, owing to the poverty of the conditions in which they live and their squalid surroundings, are lacking in many of the ordinary experiences of life when they enter school at five. They do not, therefore, in this department, reach the stage when they are interested in other lands and other times; at any rate, not to the extent of giving a definite course of lessons in such subjects. I consider that the history suggested by the chart belongs, for most children, to the age seven to eight, as does the transition from nursery tales to the true stories of other ages. 356 REPORTS ON THE STATE OF SCIENCE, ETC. The relative value of time particularly has no significance for children up to seven. If their interest in children of other lands is aroused by any incident, then that is followed up and information given, but for the most part their stage of development is such that the “ here ” and the “‘ now ” supply sufficient scope for their curiosity. With children from homes of a wider culture perhaps this ground might be covered by the age of seven, but I do not think so. I would certainly include it in the first year of the junior stage.’ General Observations. This section of the inquiry revealed the method of approach of teachers in infants’ schools rather than the content of the syllabuses of the schools. In modern infants’ schools the emphasis is placed upon the development of the child rather than upon the information taught. The distribution of the questionnaire was necessarily limited to a few representative schools: «a wider distribution might have shown more clearly what information is acquired by the pupils. This is considerable, notwithstanding the fact that neither the time-tables nor the school syllabuses are based upon subjects of instruction. Visits to a number of infants’ schools—if arrange- ments could be made for a sympathetic and skilled teacher to ask questions of the pupils—would enable a more accurate idea to be obtained as to the amount of factual information gained. It might prove to be more extensive than is generally thought, especially in relation to Science. ‘The work in nature study, in the school garden, and with animal pets, quickens observation and prompts innumerable questions ; the information pupils thus acquire is probably greater than has hitherto been appreciated. (2) Replies from Funior Elementary Schools to Questions on Grade B. The replies to questions on Grade B were received from three head mistresses and four head masters of junior schools. Unfortunately the detailed answers desired were seldom given; but in every instance the evidence afforded an illustration of the difference between the present methods of approach and those in common use twenty-five years ago. History. This difference is shown plainly in the information relative to the curricu- lum in History. Thus replies from a London head master and a Nottingham head master stated that all the suggested curriculum is taken; and that from an Ealing head mistress, “ Practically this scheme is taken simply and pictorially, minus Races of Man, references to the Great Empires, and to Islam and Semitic Races.’ Of the others, a London head mistress takes the ‘ Story of Early Civilisation’ and the ‘ Growth of Christianity’; a Cambridge head master includes the ‘ Coming of Aryan-speaking Peoples,’ the ‘ Rise and Growth of Christianity,’ and the ‘ Elementary History of Great Britain’; and a Cannock head master includes the ‘ Story of Early Civilisation,’ the ‘ Growth of Primary Civilisation,’ the ‘ Succession of Stone, Copper, Iron,’ the ‘ Introduction of the Horse,’ the ‘ Construction of Roads,’ the ‘ Development of Shipping,’ the ‘ Establishment of Persian, Macedonian and Roman Empires,’ the ‘Coming of Aryan-speaking Peoples,’ and the ‘ Rise and Growth of Christianity.’ E The time suggested for History by Mr. Wells was approximately 2 hours 25 minutes per week. This was longer than was generally given to the INFORMATIVE CONTENT OF EDUCATION 357 subject. One correspondent stated that only one-sixth of that amount was given, while another allocated one hour. It appears obvious that if the whole of the work indicated in Mr. Wells’s proposals is to be taken— certainly if it is to be taken thoroughly—a longer time is necessary. ‘Thus the reply from Kesteven stated that it is desirable that the whole suggested scheme should be taken, but that only 2 hours 10 minutes are available for both History and Geography. On the other hand, the Cannock head master thought the following parts are superfluous for junior children: “The Developing Réles of Priest, King, Farmer, Warrior’; the ‘ Rise of the Semitic-speaking People’ ; and the ‘ Rise and Growth of Islam.’ Geography. As will also be observed from the replies referring to the other grades, the work actually taken in this subject most nearly approximates to that suggested in Mr. Wells’s curriculum. In every case except one the replies stated that all contained in Mr. Wells’s outline is taken ; and the exception simply stated that no Geology is taken. Here, too, the time devoted to the subject, when reference is made thereto, approximates to that allocated by Mr. Wells. Science. (a) Botany.—In Science, however, the scope of the work attempted in the schools falls far short of what Mr. Wells regards as necessary. Biology is seldom taken, and even when taken it is not on the lines indicated. The only two replies giving any information in relation to this subject stated, one, that ‘ Succession of Living Things in Time’ is taken, and the other, that Zoology and Botany are taught in reference only to creatures and plants familiar to children. (b) Science of Inanimate Matter likewise receives somewhat scant atten- tion. ‘ Very simple principles’ are taught in one of the schools from which information was received ; Physics and Chemistry are taught in another, but not on the lines indicated ; and ‘Elementary History of Inven- tion and Discovery’ is taken in a third. But in the other replies either no mention was made or else it was stated that no part of the syllabus is attempted. (c) Physiology.—Slightly more attention is given to Physiology. ‘The Working of our Bodies’ is taught at one school ; ‘ Some Reproduction of Plant and Animal Life from Direct Observation’ in another. Elementary Hygiene was mentioned in yet another reply, and this is possibly included more commonly in the curriculum of junior schools in connection with “Health Talks,’ a universal feature of school work. The whole of the Science teaching was said in two replies to be given in the form of ‘ Nature Study.’ How much of what is included in Mr. Wells’s proposals is taken in this work was not indicated. Observations on the Proposed Curriculum. Few suggestions were made as to the inclusion of those parts of the curriculum at present omitted Only two correspondents indicated that they would like to include other sections of the work ; one wished to include all the parts of the History and Geography, the ‘ Elementary History of Invention and Discovery,’ and ‘The Working of our Bodies,’ but said that inadequate time and the necessary grouping of classes made that im- 358 REPORTS ON THE STATE OF SCIENCE, ETC. possible ; the other would add ‘ General Ideas of Evolution,’ but the size of classes, 46-48, was said to prevent it. The suggestions as to parts to be excluded were more numerous. They were : ‘ Biology section, Reproduction, Diseases, Enfeeblements and Acci- dents, Developing Réles of Priests, etc,. and Rise of Semitic People,’ © because ‘ subject matter is unsuitable and entirely outside the experience of the child.’ De All the Science except ‘Elementary History of Invention and Dis- covery’ and ‘ Working of our Bodies,’ for the reason that they are ‘ too abstract and too deductive.’ 3. Geology, Pure Physics and Chemistry, because, in the opinion of the writer, ‘ The object in teaching Science in the Junior School should be rather to lay the foundation for a method of approach and orderly thinking. This can best be achieved with the teaching of Nature Study.’ 4. Physiology and Anatomy as well as Physics and Chemistry. ‘The reason given by this correspondent was, ‘The matter under the head Physiology I consider contrary to a junior child’s natural development and requirements, which should be of a constructive character.’ She also considered that the work would be hampered by size of classes, lack of specialist teachers and lack of accommodation and equipment. 5. Sections of History, Biology and Science of Inanimate Matter; the reasons given for exclusion being : ‘(a) History—Too much time spent on early World History leaves no time for modern inventions, great social reformers, and gradual changes in social life. One hour is all that I could allow in the crowded curriculum of a Junior School, with its need for the three R’s and numerous activities. ‘(b) Physics and Chemistry.—Too advanced ; besides, no facilities. ‘(c) Physiology.—Personal hygiene only necessary at this stage. Repro- duction should be taught when quite ‘young by parent, or if at school, at the adolescent stage. ‘(d) Biology—(Theory of Byoletioa’ in Human and Plant Life.) I think these children are more interested in things as they are at present.’ Having regard to the position revealed in relation to the Science syllabus, it would appear that this is a subject calling for detailed consideration by the Research Committee. General Observations. The History and Geography taken in schools, especially the latter, correspond somewhat closely to the recommendations in Mr. Wells’s chart. So far as History is concerned, there are marked differences in the scope of the work attempted in different junior schools. More or less drastic changes are taking place in the method of approach to this subject, and World History is receiving increasingly greater attention. ‘The replies to the questionnaire show that the schools are at present passing through a period of transition in respect to the teaching of History. Similar changes relative to Geography have been taking place for the last thirty years at least, and the syllabuses of. the majority of schools include most of what Mr. Wells advocated. In regard to Science there is much variation in the work taken in junior schools themselves. But even if this is borne in mind, there is, speaking generally, a great difference between what is actually taught and what Mr. Wells advocated should be taken. Possibly in reference to junior schools the INFORMATIVE CONTENT OF EDUCATION 359 same observation might be made as was offered when infants’ schools were under consideration, viz., that much of what is suggested should be learned by pupils is already taught, although not as part of a separate subject. Some of the information included in Botany is taught in Geography, talks of other lands, or Nature Study. The part played by the aquarium (a feature of many schools) in this work was not indicated in the information received. Health talks are included in the syllabus of all junior schools and experi- mental work taken to illustrate them. Some Physiology and Anatomy are doubtless taught in connection therewith. Possibly the modern methods of education adopted in schools, and especially the new approach to the curri- culum, have handicapped the inquiry in its efforts to discover what is the actual information gained by pupils during the years they spend in the junior schools. It is obvious, however, that more money will have to be spent on equipment and books to enable the schools to do justice to the expansion in the curriculum dictated by the needs of to-day. (3) Replies received from Senior and Central Schools working under Elementary School Regulations to Questions on Grade C. The questionnaire on Grade C was submitted to teachers in various types of school working under the Elementary School Regulations. These included selective and non-selective central schools, and rural and urban senior schools. Some were departmental schools either for boys or girls, and others were mixed. ‘The schools to which the inquiry was sent may thus be taken as representative of elementary schools providing for children of the ages 11 to 14 plus. In the selective central schools the majority of the pupils continue in attendance until the age of 15. An examination of the replies indicated that the analysis of Mr. Wells’s proposed curriculum did not convey to all those who received it an ade- quate idea of what the address with its chart conveyed to those who heard it delivered at Nottingham. The aim of Mr. Wells did not always appear to be fully understood ; certainly his reasons for advocating this minimum of informative content of education were not fully appreciated even if they were comprehended. ‘This was unfortunate, since it may have led corre- spondents to regard the inquiry from the wrong angle. The replies revealed a wide divergence between present practice and Mr. Wells’s proposals, and to summarise them briefly is a rather difficult task. In these circumstances possibly the best course will be to indicate the sections of the subjects included in the proposed curriculum which are taken in each school. History. In the Lowestoft school, which is a selective central school, the sections taken are: ‘ National and Imperial Boundaries.’ “Economic Changes in History.’ ‘Rise and Fall of Empires and Powers.’ ‘History of War.’ In regard to the remainder the head master wrote: ‘It is perhaps fair to say that most of the remaining parts might be “‘ advantageously included.” Some of the phrases are rather staggering for a school curriculum, but they probably mean much less than they appear to mean.’ 360 REPORTS ON THE STATE OF SCIENCE, ETC. A Bristol girls’.school includes in its History syllabus : ‘ Development of Imperial and National Boundaries’ ; ‘The Rise and Fall of Countries and Empires’ taken generally ; and no suggestion was made of desirable additions, though the opinion was expressed that ‘ Leading Theories of Individualism, Communism, Corporate State ’ should be excluded. ‘The reasons given for this opinion were that girls in a non-selective central school ‘ are intellectually incapable and of insufficient experience at their age, to benefit by study of these subjects,’ and that ‘the girls come from different homes, where political opinions may be freely expressed at home, and they may be (and probably will be) strongly biassed towards a political party supported by the home.’ A school in Oxfordshire takes : “The Development of Existing National and Imperial Boundaries ’ ; “The Increasing Importance of Economic Changes in History ’; and “The Search for Competent Economic Direction.’ The head master would also like to include ‘Elements of Political Theory’ for pupils during the 14-15 year, but he would exclude the “History of War,’ the ‘ Rise of Russia,’ the ‘ History of the Baltic.’ His reasons are lack of time, and the unsuitability of these subjects for rural children who are more practical than bookish in type. ‘ Theories of Individualism, Corporate State and Communism,’ he wrote, ‘ could not be studied with profit by rural elementary children until 14-15, as they have no background to which to attach such knowledge and are too young to have opinions thereon of their own.’ A Staffordshire head mistress reported that ‘ practically all is taken in one syllabus or another with the exception of ‘‘ Detailed Study of European History ”’ as mentioned in Mr. Wells’s speech. . . . All of it is taken in so far as the sections make contact with English or Imperial History.’ In this school the ‘ special bias is given to (1) Social History and (2) Imperial History.’ This head mistress thought that when 14-15 is established as the last year of school life a fairly comprehensive study of Modern European History might well form the basis of this year’s work in History and Economics. At present the available time does not permit of this being included. It also prevents the inclusion of the ‘ Rise of Russia,’ the ‘ Rise of Dutch Power,’ the ‘ Unification of Germany and Italy,’ and the ‘ Leading Theories of Individualism, Corporate State and Communism.’ Even if time did permit, however, she would not include the ‘ History of War.’ Another head mistress who has charge of a school in Hull includes these sections : * Development of Existing National and Imperial Boundaries.’ “The study of such phenomena as: Rise and Fall of Ottoman Empire, taken baldly as it impinges on the Crusading Era and the Renaissance.’ “History of the Baltic.’ ‘Rise and Fall of Spanish Power.’ She reported that an approach to the ‘ Leading Theories of Individualism, Corporate State and Communism ’” has emerged from the wireless talks on “ History traced Backward ’ and ‘ Topical Talks.’ Of the remaining correspondents one reported that the History taught is not on the lines of the suggested curriculum but more in accord with the section under the heading of ‘ Social Mechanism’; and the other gave the bald answer ‘ None’ to the questions, adding that the whole INFORMATIVE CONTENT OF EDUCATION 361 of the Informative Content of Education ‘is wholly unsuitable for the immature minds of children 14-15 years of age.’ Geography. As was noted when reference was made to the replies to questions on Grade B, the Geography taken in the school corresponds closely to that contained in Mr. Wells’s syllabus in that subject. Thus of the Lowestoft school it was reported : ‘ All parts are taken (using discretion about “ detailed and explicit”’)’; of the school in Torquay, ‘ Broadly speaking, we cover the suggested content, but the statement in the speech has an academic flavour shunned by us, especially when dealing with B and C classes. We probably teach as much as Mr. Wells wants us to teach, but in an easier atmosphere than he creates’; of a girls’ school in Stafford, ‘ Taken almost exactly as indicated, except that the Geology side is only simply touched upon’; and of a Hull girls’ school, ‘ All except the Geology of the World.’ Of the others, it was said of one that Economic Geography, local Geology and World Geography are taken ; and of the other, ‘ Economic Geography and Geology of World are taught generally.’ A note was made in two instances that World Geography is not taken in a detailed and explicit but in a general manner. Social Mechanism. The information under this heading was not given so fully as that included in Geography. Indeed, in one reply it was ignored and in the others only a small part was included. Thus in the selective central school in Lowestoft, ‘Communications and Trade, Production and Manufacture, and Money’ are taught ; in a Bristol girls’ school, ‘ A Short History of Communications and Trade, a History of Innovations in Production and Manufacture, and the Réle of Property and Money in Economic Life’; a rural school in Oxfordshire includes in its syllabus ‘ A Short History of Communications and Trade’ taught as the opportunity offers in the History and Geography lessons ; a girls’ school in Stafford takes ‘ Short History of Communications and Trade, the History of Innovations in Production and Manufacture,’ but admits that they are very inadequately covered, and only deals with the ‘Réle of Property and Money in Economic Life’ as it affects the other sections of the subject ; and a girls’ non-selective school in Hull includes ‘ Short History of Communications and Trade’ and ‘ A History of Innova- tions in Production and Manufacture,’ not as a definite study but as ideas thereon emerge more or less definitely. The head master of the rural school, while wishing to include more detailed study of what he already takes, would definitely exclude ‘ 'The Réle of Property and Money in Economic Life.’ A head mistress said she would never include in a girls’ curriculum any studied course on ‘ The way in which fluctuations of money affect ‘‘ industrial windmills” and Significance of Inflation and Deflation.’ Personal Sociology. Less is taken of the work suggested in this section than of that suggested in any of the other sections. Only very small fragments of it appear to be attempted and the replies were sometimes rather vague. ‘Thus in reply to questions on this part of the suggested curriculum, one stated ‘ General Social Development is taken.’ In other cases the part taught was indicated, e.g. ‘ Man’s relationship and duty to his neighbour, and nationally to other N2 362 REPORTS ON THE STATE OF SCIENCE, ETC. countries’ in one; ‘ General ideas of relation of self to universe,’ taught incidentally in History and Geography, in another, of which the head master wroté, ‘ but details too abstract for rural children of 11 to 14 years of age’; ‘Taken, but on rather different lines. Comparative Religion is dealt with only in Imperial History and Geography. No great emphasis is given to direct attention to the choice of a métier’ in a third. In one girls’ school Comparative Religion is taught, the oldest group taking a short course of study in the main teaching of Buddha and Mohammed at the end of the fourth year. One head master thought that ‘ Incidental mention of other religions and general study of types of civilised life’ might be taken, but regarded the remainder as too abstract for elementary school children. A head mistress, too, commented on this point, stating that she ‘ does not consider children of this age-group are capable of comprehending the ideas contained in the suggestions.’ General Observations. An analysis of the replies reveals a number of interesting facts, the most outstanding being the degree of freedom enjoyed by teachers in elementary schools in arranging the curriculum of the schools for which they have responsibility. As a consequence of this there is a great variety of curricula in English schools catering for children of the same age, a variety which characterises both the subjects taken and the sections of the subjects included. Another noteworthy fact which emerges is that there is a marked tendency to give greater attention to practical subjects, and the time available for giving definite information is therefore more limited than it was in the early days of this century. More germane to the present inquiry is an opinion which in one form or another finds frequent expression. It is, that the curriculum outlined by Mr. Wells, though it may be desirable, is beyond the capacity of the pupils of this age. ‘The opinion is expressed somewhat hesitatingly by these correspondents in elementary schools; indeed, they more often indicate it by the omission of any reference to sections; but it is none the less obvious. It may be that the suggested curriculum is too ambitious and com- prehensive ; that the subjects are beyond the capacity of the pupils. But since many of the sections are taken in the schools—though not all of them in any one school—only actual experiment can afford conclusive evidence of how much could be taught, if adequate conditions were obtained and schools were appropriately staffed. Meanwhile the inquiry itself will without doubt have a stimulating effect. REPLIES FROM PREPARATORY SCHOOLS AND DEPARTMENTS TO QUESTIONS ON GRADE C. Since preparatory schools and preparatory departments of public schools cater for children of the same age-group as those found in the senior schools in the elementary education system, the same questionnaire was submitted to six schools of this type. Only three replies were received. Of these one was in the following terms : ‘I do not think it is possible to give a formal detailed reply to the questionnaire on Mr. Wells’s views of History. It is useless to con- sider Section C, ages 11-14, except on the assumption that the ground INFORMATIVE CONTENT OF EDUCATION 363 suggested for the stages A and B has previously been covered ; the know- ledge and capacity assumed for these ages as possibilities seem to me absurd.’ History. The other two indicated what sections are taken in History and Geography. At Brentwood School, in History ‘ The Rise and Fall of Spanish and Dutch Powers’ come in for 11-14. The rest of the syllabus more in the Sixth Forms ; parts of the 7-11 are given to 11-12 boys.’ At Gadebridge Park the syllabus includes ‘ The Rise and Fall of Spanish and Dutch Powers, Unification of Germany and Italy and the History of War.’ Geography. At Brentwood ‘ Most of this is covered,’ while at Gadebridge Park the parts of the suggested syllabus taken are : “World geography. Different types of population in the world. Developed and undeveloped resources of the globe. Devastation of the world’s forests, dongas and.the like ; natural resources.’ Social Mechanism. At the first-named school this ‘ comes in Lower Sixth’; no mention was made of it in the reply from the second school except that the head master thought that the following might be advantageously included in the curriculum : ‘ Short history of communications and trade’ and ‘ A History of Innovations—perhaps.’ His colleague at Brentwood School observes in reply to the inquiry as to what might be added : “Most of syllabus is taught in different parts of the school ; I should like to include Physiology but at present ‘‘ Reproduction ” is the chief part dealt with ; accidents we deal with only in the Ambulance section of the cadet corps.’ Sections Excluded. The replies to the question on parts that should be excluded were of interest. In one case they included all given under Personal Sociology, which, said the writer, ‘should only be discussed with well-balanced senior boys having other main interests in life; a boy may easily lose his mental balance.’ This he gave as the reason for the exclusion of this section of the curriculum, ‘ because,’ he added, ‘I have had personal experi- ence of undergraduates breaking down mentally.’ In the other case the correspondent would not include : ‘ Geology of the World. Increasing importance of economic changes in History, etc. The Réle of Property in economic life. A short history of general ideas. Comparative Religion. Study of social types leading to choice of réle.’ In explanation of this he stated : “The preparatory schools, owing to the immense importance and time given to Classics and Mathematics and the ignoring by Public Schools of Geography, are only able to devote some 2 hours a week to “Geography ” and Geology can well be left to the Public Schools. Naturally some Geology is necessary to the understanding of even elementary Geography. No Geographer is qualified to teach Geology ; 364 REPORTS ON THE STATE OF SCIENCE, ETC. it is outside their province. Lack of space makes me dogmatic. The other items are outside, or ought to be, the understanding of a normal, healthy boy. Could such subjects be made interesting to the immature ? I doubt it.’ When referring to the obstacles in the way of introducing a ‘ Short History of Communications and Trade’ and possibly ‘A History of Innovations,’ he wrote : “'The fact that our present curriculum takes a normal boy all his time to assimilate, whether he works for the Naval Entrance Examination, the Common Entrance Examination or a Scholarship Examination. We must leave the Public Schools something to teach their boys. Facts, not ideas, come more easily to boys between the ages of 11 to 14, therefore make hay . . . We hate teaching theories and politics to boys, unable to refute what is told them successfully ; it’s unsporting and un-British.’ REPLIES FROM SECONDARY SCHOOLS TO QUESTIONS ON GRADE C. An analysis of the replies presents some difficulty. This arises partly from the variation of schemes and the distribution of the sections taken over a wider age-range and partly from the method of approach to the subject, a method which differs considerably from that indicated by Mr. Wells. The questionnaire referred to the ‘ Informative Content’ of an education which might be—Mr. Wells thinks should be—given to all pupils by the age of 14. ‘ Our educational system is so different from that envisaged by H. G. Wells that it is difficult to comment,’ said Mr. Lyon of Rugby. ‘Mr. Wells is an interesting theorist ; but if the children whose capacities he estimates so glibly were before him in a class he would discover in a very salutary way that their reactions to knowledge he prescribes were rather different from what he imagines them to be,’ wrote Miss Clarke, of Manchester High School for Girls. These observations raise an important question which appears to have been in the minds of many correspondents. This is: ‘ How far are the pupils in schools able, at the ages stipulated, to receive the information included in the outline syllabus of Mr. Wells?’ Possibly the teachers underestimate the capacities of their pupils, as Mr. Wells suggests ; but it is noteworthy that in these returns from secondary schools there is unanimity regarding this point. What was indicated by Mr. Wells as necessary is thought to be beyond the capacity of the pupils at the age at which it is suggested that it should be taken ; but in some cases the informa- tion is included for an older age-group Thus Miss Gwatkin (Streatham Hill Girls’ School) wrote : ‘We keep most of our girls till 18 and nearly all of them until 17, and prefer to deal with many of the matters in your schedule when they are over the age of 16 and more mature.’ Mr. Barton, of the Grammar School, Bristol, expressed the opinion that “Here and there, from the standpoint of a practical teacher, the scheme suggests precociousness, and I dare say the air of an ambitious set-out is partly accounted for by the difficulty of concise indications in other than academic language. The word “ informative ’’ seems to me a little mis- leading ; e.g. our “‘ ideas of the relation of oneself to the Universe ’’ come largely into the realm of speculative opinion and feeling rather than of information in the usual sense. Such doubts however are inevitable, and broadly speaking I think the consideration of the scheme has value, if only INFORMATIVE CONTENT OF EDUCATION 365 to encourage the taking of a wider and more fundamental view of the schoolmaster’s objects.’ It is because the Committee of Section L desire, if possible, to encourage the taking of a wider and more fundamental view that this inquiry was instituted. But it is necessary to know how much is already attempted, in which direction expansion is necessary and how far such alterations are possible and desirable before any conclusions can be formulated. Mr. Evans (Woodhouse Grammar School, Sheffield) indicated another reason why the whole of the Informative Content of Education as contained in Mr. Wells’s suggestions cannot be given : ‘ Our opinion is that the syllabus of work suggested by Mr. Wells is far too ambitious to be tackled in any school with any degree of success with pupils up to the age of 14 plus. . . . So far as History is concerned, most of the work under Grade B is taken here in Grade C. I am sure that any attempt by the average teacher to try to cover the ground suggested by Mr. Wells would end in chaos and confusion in the poor child’s mind, and he would derive very little benefit from the attempt to teach him all that is suggested. It is possible, of course, that a teacher who is a real genius at his work might make a success of this colossal task.’ The last sentence suggests that, given the right teacher, the pupils could be given the information included in the scheme outlined by Mr. Wells. If this were so, then the work of the Committee would include recommenda- tions as to the ways and means of providing the right teachers. History. The opinion that even a teacher who is a genius could teach all that was suggested is not shared, however, by all those who sent replies to the questionnaire, some of whom would not include all sections of the work. For example, the Head Master of Bristol Grammar School said of ‘ Elements of Political Theory,’ ‘Development of Existing National and Imperial Boundaries,’ ‘ Increasing Importance of Economic Changes in History and the Search for Competent Economic Direction,’ that they should not be included, as the problems require a riper mentality than is possessed by the average boy of 16. In this school, consideration of these sections is deferred to an advanced course, and even then the treatment is less formal than incidental to the work in literature, art and general essays. The Head Master of Rugby suggested that pupils should be given a thorough knowledge of the History outlined in Grades A and B (i.e. the parts suggested to be taken by pupils below 11 years of age), and 50 per cent. of Grade C, substituting the further study of British and Imperial affairs for the other half. This is suggested, however, for pupils aged 14 to 16. The Head Mistress of Manchester High School for Girls stated : ‘In our history syllabus, the early civilisations, and much of the attendant matter suggested by Mr. Wells, are taught at the age of fourteen. This year’s course ends with the fall of the Roman Empire; and the history of Great Britain, of her European neighbours, and their overseas expansion, which Mr. Wells suggests should be completed before the age of fourteen, occupy our girls for another four years of their school course.’ Only Sheffield Woodhouse School gave an affirmative reply to the questions on the following parts of the scheme of History: ‘ Development of Existing National and Imperial Boundaries,’ ‘ Increasing Importance 366 REPORTS ON THE STATE OF SCIENCE, ETC. of Economic Changes,’ though the Head Mistress of Clapham Secondary School stated that practically all were included in the instruction for the period ending 14 years of age, except such as are postponed for the ages 14to16. The Head Mistress of Manchester High School reported that such parts are taken as fall within the History syllabus for School Certificate (English History 1783-1914, and European History 1789-1914), while Liverpool Collegiate School said they are taken not as a course but as they arise from the study of Europe. It is noticeable that while the Head Master of Bristol Grammar School does not include the parts to which reference is made in the foregoing paragraph and the Head of Sheffield Woodhouse School does, in relation to ‘ Study of such phenomena as: Rise and Fall of Ottoman Empire; Rise of Russia; History of Baltic; Rise and Fall of Spanish Power and of Dutch Power; Unification of Germany and Italy,’ the former replied ‘Yes’ except in reference to ‘ History of Baltic’; and the latter replied ‘No’ but thought the ‘ Rise and Fall of Spanish and Dutch Powers ’ might be included. Both take the ‘ Unification of Germany and Italy ’ with pupils 14 to 16. ‘These sections are also taken at Streatham High School and were said to be included by Liverpool Collegiate School in the General and World History Course which is given as a preliminary background for English and European History. There is greater unanimity regarding the remaining sections: ‘ Leading Theories of Individualism, Corporate State, Communism,’ and the ‘ History of War.’ Streatham High School reported that the first is taught incidentally, but Bristol Grammar School and Sheffield Woodhouse School both stated definitely that it should not be taught as the pupils have not sufficient knowledge on which to base theories. Liverpool Collegiate School reply expressed the opinion that it should only be taken in the Sixth Form ; since if attempted before, the teaching can only be superficial and may be misleading. In no instance was the ‘ History of War’ taught. After stating that it is unsuitable except with Sixth Form, the Head Mistress of Manchester High School proceeded to suggest that it should not be included at all, its place being taken preferably by the ‘Achievements of Peace.’ Subsequent to writing the above report a further reply was received from Dudley Girls’ High School. This stated that ‘All the suggested subjects are included in the curriculum, although it is not built round these points but differently grouped, i.e. we do not work solely from this angle and include much that is not mentioned. We lay more stress upon British History.’ The periods studied at this school are: To the French Revolution by pupils 11 to 14 years of age; and from the French Revolu- tion to the present day by pupils between the ages of 14 to 16. Geography. . The instruction in Geography given in the schools appears to approximate more nearly to Mr. Wells’s scheme than does that in any other subject. In Bristol Grammar School it was said that Economic Geography and Geology of the World is covered in an elementary and unpretentious way by the pupils aged 11-14, and most of the other sections might be covered if time allowed. Rugby reported that all of it is included in the syllabus ;_ Liver- pool that ‘ all may be included but owing to lack of time some parts of it . may not be reached until the 14-16 stage,’ and added, ‘ This is not on the ground of its unsuitability but simply because time does not allow.’ Some of the correspondents indicated their method of approach. Thus INFORMATIVE CONTENT OF EDUCATION 367 the Streatham Head Mistress recorded that ‘ World Geography is taken at the age of 10 plus in the form of journeys and history of explorations. So there should be knowledge of the (i) Continents; (ii) kinds of religion ; (iii) occupations.’ This is for pupils 11-14. For those 14-16 she said: *Then World Regions are taken as synthesis of previous building up of knowledge of various parts.’ In Manchester High School for Girls this Geography is taught to pupils 11-14 incidentally as the study of the various world regions proceeds, but is not isolated and taken in regard to the world as a whole. ‘Thus most of the ground is covered by the age of 18. In her general remarks the Head Mistress said: ‘'To propose covering the ground by the age of 14 is absurd. The limitations in general knowledge in children of 11 to 13 make the teaching of scattered items of general information purely dog- matic.’ A similar caveat was entered by the Head Master of Sheffield Woodhouse School. After stating that ‘General knowledge of natural resources and their exploitation ’ is taken, he proceeded : ‘ To suggest that children of this age should have detailed and explicit acquaintance with undeveloped resources of the globe seems to me fantastic ; to begin with I find it difficult to understand what is meant by “‘ detailed and explicit acquaintance with world geography, with different types of population, and the developed and undeveloped resources of the globe.” ’ Geology is not, apparently, given so much attention as the other sections. In Sheffield Woodhouse School it was said to be least stressed. At Clapham it is not ‘ taken as a separate study but references to Geology and geological theory are not infrequent in the course of lessons in Geography.’ One correspondent, the Head Mistress of Streatham, expressed the opinion that ‘ Geology as such should not be included. This is a science in itself, and too difficult. Geomorphology would be a better word, but even that could only be taken very generally. Geology should be left to University study.’ Social Mechanism. The replies to questions on Social Mechanism were not helpful. The first two sections : ‘ Short History of Communications and Trade,’ ‘ History of Innovations in Production and Manufacture,’ were said to be taken in Bristol Grammar School and Liverpool Collegiate School, but in each case by pupils 14 to 16 years of age. In relation to the remaining sections : ‘ The Réle of Property and Money in Economic Life,’ ‘ Knowledge of Conventions of Property and Money,’ ‘ Way in which Money has changed Slavery and Serfdom into Wages and Employment,’ Way in which Fluctuations of Money affect ‘“‘ Industrial Windmills,” ’ ‘ Significance of Inflation and Deflation,’ four made no reference and a fifth replied that they should not be taken since they require a riper mentality than is to be expected before the age of 16. From Streatham High School the reply to this section was: “A regular course of economics lasting two years is taken in the Sixth Form (16-18). Usually economic history or a course of modern problems is also taken.’ The Head Mistress of Manchester High School stated: ‘A good deal of what is described as Social Mechanism finds its way into history teaching. 368 REPORTS ON THE STATE OF SCIENCE, ETC. Simple economics and economic history are absolutely essential to a just appreciation of historical development as a whole.’ Again there is the suggestion that the information contained can only be taken with a Sixth Form and that below that stage only very superficial matters can be dealt with. Personal Sociology. The least satisfactory replies had reference to the section on Personal Sociology. Three made no mention of it and with slight exceptions the others were of the opinion that the various subjects should not be taken. The exceptions were in the case of Streatham High School. There “ Comparative Religion ’ was said to be taken in Divinity ; ‘ General Ideas of the Relation of Oneself to the Universe ’ was said by Liverpool Collegiate School to emerge from religious teaching and addresses at Prayers with the whole school ; and ‘ General Study of Social Structure, etc.’ was given by a Bradford head master as a part that might be taken. The Head Mistress of Manchester High School is of the opinion that “The material outlined under Personal Sociology is not suitable before the last year in the Sixth Form (17-18) and can be approached only in the most elementary way even then.’ ‘The Head Master of Bristol Grammar School remarked that ‘ It is questionable whether the detailed consideration of much of the matter under Personal Sociology is proper to the school stage at all.’ General Observations. The replies received from secondary schools demonstrate the influence of examinations upon the syllabuses of work. While the statement that the First School Examination controls the work in secondary schools may be an exaggeration, the fact that it does greatly influence both the scope of the syllabus and the method of approach is obvious. The thorough and sometimes detailed knowledge required to answer examination papers has a limiting effect upon the scope of the work attempted. The practice of taking thoroughly what is attempted may also account for the opinion that some sections should not be taught. On the other hand, the opinion that some parts of what Mr. Wells would include should not be taught to school pupils was definitely expressed by head teachers of experience and of known progressive views. ‘This was especially true of two sections, Social Mechanism and Personal Sociology, and it is only fair that the strong opposition to their inclusion should be noted. SUMMARY OF REPLIES. In summarising the results of the questionnaire, the two features which call for comment are : 1. The consensus of opinion that the informative content of education outlined by Mr. Wells is both too wide in scope to be covered during the present school life of the great majority of children of this country, and too advanced in its demands upon the capacity of the pupils for whom the various sections of the subjects were suggested. 2. The differences of opinion in relation to what can be included in the curriculum ; what some correspondents believe cannot be taken with pupils of a given age-group and cannot be included within the scope of a reasonable curriculum, is actually taken in other schools with pupils of the same age. INFORMATIVE CONTENT OF EDUCATION 369 In reference to the first it should perhaps be observed that the phraseology used by Mr. Wells was that most suitable for the audience on the occasion of the delivery ; but it was not always appropriate for use in schemes of work for elementary or secondary schools. As one correspondent wrote : ‘Some of the phrases are rather staggering for a school curriculum, but they probably mean less than they appear to mean.’ In illustration of this statement reference may be made to some sections named in the outline given by Mr. Wells. ‘Elementary ideas about human cultures and their development in time,’ when suggested for the infants’ schools, sounds formidable. But when the actual stories told to children of this age are recalled, including the Biblical stories, stories of Hiawatha, etc., and when the outlines of History are examined from this angle, the suggestions may not appear quite so alarming. Similarly, ‘ States of Matter,’ for infants, has a terrifying sound. But talks on ice, water and air in some form or other, and in association with some experience or activity, are taken in every school. Biology, Zoology, Botany and Physiology mentioned in any curriculum for very young children would immediately arouse suspicion, if not antagonism ; yet it is doubtful whether the whole of Mr. Wells’s suggestions are not included in Nature talks, Observation Records, Gardening and such-like normal activities of nearly every infants’ school in the country. The differences between what is actually taken and what Mr. Wells suggested in regard to other age-groups may be more marked ; but the contradictory nature of some of the replies appears to emphasise the need for further and fuller inquiry. With regard to some of the work suggested for these groups it may be found that the terminology has been too readily accepted as ambitious and pretentious ; and insufficient attention has been paid to the actual content of the proposed curriculum and to the real scope of the work already included in schemes of work. Such an approach may account for the reply ‘ None’ given to the whole questionnaire, the corre- spondent adding that the whole of the Informative Content of Education “is wholly unsuitable for the immature minds of children of 14-15 years of age.’ An ex cathedra pronouncement of this kind may denote a reluctance to experiment, and a tendency to assume that all is well in our present curriculum. In further illustration reference may be made to the sections of History for Grade C, ‘ The increasing importance of economic changes in History,’ and especially to ‘The search for competent economic direction.’ So expressed, they are, in relation to an elementary school curriculum, almost awe-inspiring ; yet judging by the information received there are some senior schools in which both sections are taught and taught effectively. The Committee are of the opinion, therefore, that further investigation is desirable to discover how far the actual teaching in the schools, regardless of the terminology employed, does cover the various sections of the subjects to which reference is made in the outline of an Informative Content of Education. Possibly there are parts of the curriculum suggested by Mr. Wells which cannot be taught either because they are beyond the capacity of the pupils or because the time factor will not allow them to be included. In relation to the first of these, the following observations of Sir Richard Livingstone, speaking as President of Section L at Blackpool, may be recalled : ‘TI should like to suggest certain principles which we must observe if our efforts are to be successful, and to which little attention has hitherto been paid. . . . The first of these principles is that education must be 370 REPORTS ON THE STATE OF SCIENCE, ETC. adjusted not only to the natural capacities of the pupil but also to the stage of development which his brain has reached ; that certain forms of study are appropriate to certain ages. That is a platitude. What need then to stress a principle which everyone accepts? Yet, if accepted, is it remembered by an age which has acquiesced in the idea that most of the population should leave school at 14, and is now comforted by the thought that in future they may not leave it till a year later? At the ages of 14 or 15 the mind cannot cope with, if it can conceive, the subjects which compose a liberal education and are vital to the citizen. A boy reads literature—‘‘ Hamlet ” or ‘‘ King Lear ’’—and should read them. But what can the profound scepticisms of Hamlet, the passion and agony , of Lear mean to him? He reads history. Can he form a true con- ception of Charles and Cromwell, Bismarck and Napoleon III? At 18 we may scan the surface of history and literature, but we cannot see below it. Still more does this apply to the political questions on which an elector has to express an opinion. Unless you believe that these subjects are not meant for the masses and that the voter needs no further education for his duty than experience of life, the newspapers, and the speeches of political candidates, you are admitting the absurdity of an education which stops at 14 or 15.’ In relation to the second reason—the time factor—further inquiry into the actual curricula of the schools is necessary before a final conclusion can be reached ; such inquiry may even involve consideration of the relative importance of various sections of the curriculum as instruments of learning and as a means for the preparation of pupils for life. In the meanwhile an inspection of the returns received shows, ashas already been indicated, divergence of practice and many contradictions in the opinions expressed. These were so marked that the following list has been prepared. GRADE B.—REPLIES FROM JUNIOR SCHOOLS. History. No. of replies which gave in- formation allowing analysis to be made :— Chart. Speech. ‘ ne, | || oe cluded. | cjuded | cluded. | T°P!Y: Races of man . : : : , ‘ I 2 2 2 Early civilisa- | Story of early civilisation, tions. growth of primary’ . civilisation ; 6 - - I Developing réles of priest, king, farmer, warrior . 3 I 2 I Succession of stone, copper, iron 3 I I I Introduction of horse 3 I I 2 Construction of roads 4 I - 2 Development of shipping 4 I = 2 Rise of a ne peoples I I 4 I INFORMATIVE CONTENT OF EDUCATION 371 Chart. Speech. No. of replies which gave in- formation allowing analysis to be made :— General signifi- cance of : Persia. Greece Carthage Rome China. America Islam . Christianity . General idea of break-up of Christendom and Appearance of modern sovereign states Elem. history of Great Britain Elem. history of | France Types of country Floras and faunas General survey of world as human habi- tat and : | Coming of Aryan- aa ing peoples Establishment of : Persian Empire Macedonian Empire . Roman Empire . Rise and growth of Islam Rise and growth of Christianity Geography. Precise ideas of type of country Distinctive floras and faunas of main regions Sort of human life lived in each region , In. | Might | Should; yy, cluded. | beim- | be ex- | 7) ‘| cluded. | cluded. | 7©P*Y set a ae 4 I = 2 2, I 2 Ps 2 I 2, 2 I I 2 3 I I 4 2 2 I 2 z I I 2 3 I I 2 3 I I Boys nae Ruel y ek tt I I eat lB | 2 I I 3 3 I a 4 1 I - | 5 6 - - I + 4 7 3 = = I 4 = a 3 6 = - I + 7 3 3 372 REPORTS ON THE STATE OF SCIENCE, ETC. No. of replies which gave in- formation allowing analysis to be made :— Chart. Speech. Mee cee In- 18: No | cxided | HE; | BOSE | epty | Knowledge of topography | | to enable pupils to | know the position, | | reason for position, | | and kind of places well- | | known cities are— | | London, Rio, New | York, Rome, Suez 4 - - 3 | A little map-reading eee - - 3 Source of power | and wealth . 6 - - I Biology, Zoology and Botany. Zoology and Botany, in- cluding ex- | tinct forms | and their succession in | | | time . a ae : : : P Id b=) ee Succession of living | things in time I | - 4 ao Geological ages SS A aiiies General ideas | about ecology | | and__ evolu- | | tion : | Processes in prosperity, | decline, extinction and replacement of species ed aa 4 2 Story of life from the beginning : : ~ I 4 2 | Emergence of sub-man ' and gradual emergence | of mankind - te Wee 2) Science of Inanimate Matter (Physics and Chemistry). Leading up | to modern concepts of | é matter I - 5 I Mechanism and power re [Bac : : : wi eo - | 4 2 i as INFORMATIVE CONTENT OF EDUCATION 373 Chart. Speech. No. of replies which gave in- formation allowing analysis to be made :— ’ 23,| Mt | a) xe cluded. | cluded. | cluded | T°P*Y- Elementary his- | tory of in- | vention and | discovery Nemes : : ; 5 2 I a I | Foundation of pure phy- sics and chemistry on modern lines I - 5 I Physiology. Physiology and | Anatomy. Clear, general ideas of : Animal _ re- production | Reproduction - I 6 - Plant repro- duction. P : E : - I 6 - Working of our bodies I I 5 - Elementary pathology : Chief diseases =| "fal lenses Enfeeblements - - 7 - Accidents - - 7 - GRADE C.—REPLIES FROM SENIOR SCHOOLS. History. No. of replies which gave in- formation allowing analysis to be made :— Chart. Speech. fia ne || boca Nene cludec. | cluded. | cluded. Dye Elements in political theory Development of existing national and imperial boundaries 374 REPORTS ON THE STATE OF SCIENCE, ETC. No. of replies which gave in- formation allowing analysis to be made :— Chart. Speech. ees nee In- 18 “a Nolan. cluded.| cided, | cluded, | 7°PIY- Study of such phenomena as: Rise and fall of Otto- man Empire 5 I - 2 Rise of Russia 4 = I 2 History of Baltic : 4 - I 4 Rise and fall of Spanish power 2 - - 5 Rise and fall of Dutch power . 2 - - - Unification of Germany and Italy . : - 2 - 5 Leading theories of : Individualism - I 2 4 Corporate state . - I 2 4 Communism - I 3 3 History of War I - 2 4 Increasing im- portance of economic changes in history 2 = = 5 Search for com- petent econo- mic direction I I - 5 Geography. Detailed and explicit ac- quaintance with world geography Bod oe ri 3 Different types of popula | tion . - As N= = 3 Developed resources of | globe : A ly 2 = - 3 Undeveloped resources of globe ; 4 - I 2 Devastation of forests 4 - - 3 Replacement of pasture by sand deserts through haphazard cultivation . 4 - - 3 Waste and exhaustion of natural resources, coal, petrol, water, etc. 4 - - 3 ST tA ei Fae es — I a INFORMATIVE CONTENT Chart. Economic Geography . Geology : Short history of communi- cations ‘and trade . History of in- novations in production and manu- facture Réle of pro- perty and money in economic life: Short history of general ideas : Comparative Religion Speech. OF EDUCATION 375 | No. of replies which gave in- | formation allowing analysis Social Mechanism. Knowledge of conven- tions of a and money . Way in which money has changed slavery and serfdom into wages and employment Way in which fluctuations of money affect dustrial windmills ’ Significance of inflation and deflation Personal Sociology. General ideas of relation of self to universe | Primary propositions of | chief religious philosophical interpre- tations of the world to be made :— "| Might | Should | ae be in- | be ex- NOs clude’. | cluded. | cluded. EVN | 4 az ai 3 3 7 I 3 6 I — I 6 I - I 2 I 3 I 2 I 3 I ‘in- = = 3 5 = = 3 5 | 2 = I 5 | and | | I I 3 3 376 REPORTS ON THE STATE OF SCIENCE, ETC. No. of replies which gave in- formation allowing analysis to be made :— Chart. Speech. THe | Might | Should luded. | bie hee repl © * | cluded. | cluded. ae Study of social types, . | General study of social structure associated with social types ‘ I I 3 3 to direct attention to | choice of a métier : - | - 2 6 of réle. | | leading to choice | | | | GRADE C.—REPLIES FROM PREPARATORY SCHOOLS. As stated in preceding pages, only three replies were received from preparatory schools and departments. One stated that the knowledge and capacity assumed ‘ seem to me to be absurd,’ and gave no replies to questions. ‘The other two gave answers as follows : 1. History. One included ‘ Rise and Fall of Spanish and Dutch Powers.’ Rest of syllabus taken mostly with over-14’s. The other included the same two sections, but said that ‘ Increasing Importance of Economic Changes in History ’ and ‘ Search for Competent Economic Direction ’ should not be taken. 2. Geography. The first said ‘Most is covered’; the second included all except Geology, which, it was stated, should be excluded. 3. Social Mechanism. The first stated that this was taken with the Lower Sixth Form. The second considered that ‘ Short History of Communications and Trade,’ and possibly ‘ History of Innovations,’ might be included; but he considered that the following should not be taken : “ Réle of Property and Money ’ ; “ Knowledge of Conventions of Property and Money ’ ; “Way in which Money has changed Slavery and Serfdom into Wages and Employment’ ; “Way in which Fluctuations of Money affect mills’ ’ ; and ‘ Significance of Inflation and Deflation.’ “ce industrial wind- 4. Personal Sociology. Both correspondents stated that the whole of this section should be excluded, one adding that it should only be discussed with well-balanced’ senior boys having other main interests in life, as ‘ a boy may easily lose his mental balance.’ INFORMATIVE CONTENT OF EDUCATION 377 GraDE C.—REPLIES FROM SECONDARY SCHOOLS. History. Including Might be Should be section included excluded Chart. Speech. Up to] Over | Up to| Over | Up to | Over 14. 14. 14. 14. 14. 14. Elements in Po- litical Theory I = = = 2 I Development of | existing na- | tional and im- | perial boun- daries : i ; ; I I - - By hl on Study of such phe- nomena as: Rise and fall of Ottoman Em- pire F 2 I - - 2 - Rise of Russia . 2 I - - 2 = History of Baltic | — - - - 2 - Rise and _ fall of Spanish power . ; 2 _ I - I = Rise and fall of Dutch power 2 - I - I - Unification of Ger- many and Italy. | —- 4 - = 3 = Leading theories of : Individualism . - - _ - 3 2 Corporate state. - - - - 3 2 Communism - - — - a 2 History of War - - ~ ~ F pkee Increasing im- | portance of | economic changes in history I I - - 2 I Search for com- petent eco- nomic direc- tion - I - _ 2 I The other replies did not give definite points, but referred to general schemes, information e.g. * Demands School Certificate Exam.’ on the of 378 REPORTS ON THE STATE OF SCIENCE, ETC. Geography. Including Might be Should be section included excluded Chart. Speech. Remarks, Up to|{ Over | Up to| Over | Up to{ Over 14. 14. 14. 14. 14 14. Detailed and 4 said : explicit ac- “Practi- quaintance cally all with world taken geography . I I - - - - with pu- pils be- low 14.’ Different 2 said: types of “Not in population I I - - - - this form.’ Developed resources of 1 said that the globe - - — ~ - - these were Undeveloped taken in- resources of cident- the globe - 2 - - - - ally. Devastation of forests, replacement of pasture by sand de- I stated: serts through ‘Taken haphazard with pu- cultivation. | — 2 ~ - I - pils aged Waste and ex- 16 plus.’ haustion of natural re- sources, coal, petrol,water, etc. - 2 - - I = Economic I wrote : Geogra- ‘Some phy I I = — - - idea of Econ. Geogra- phy.’ Geology . I I - I I - (1 made no reference to this section.) | ee ee i i het a , INFORMATIVE CONTENT OF EDUCATION 379 Social Mechanism. Including Might be Should be section included excluded Chart. » Speech. Up to| Over | Up to| Over | Up to| Over 14. 14. 14. 14. 14. 14. | ‘ Short history of communica- “tions and trade| . ; 2 ; - 2 _ - I — History of inno- vations in pro- duction and manufacture .| . : : : ~ 2 — - I - Réle of property ‘ and money in economic life . - 2 - — 2 I Knowledge of con- ventions of pro- perty and money. | — - ~ - I I Way in which mo- ney has changed slavery and serf- | dom into wages and employment.| 2 - = - I - Way in which fluc- tuations of money affect ‘ industrial windmills ’. J lesd - - - I - Significance of in- flation and defla- tion . : eleek - - - I - | 4 replies made no reference to | | this part of the curriculum. | 1 stated that a good deal of this section was included in the History course. Personal Sociology. Including Might be Should be section included excluded Chart. Speech. Up to; Over | Up to| Over | Up to| Over 14. 14. cay 14. 14. 14. Short history of general ideas . |. : 3 ae = = 7 3 3 General ideas of re- | lation of self to the | | Universe . «.| - I - - | 2 2 380 REPORTS ON THE STATE OF SCIENCE, ETC. Including Might be Should be section included excluded Chart. Speech. Up to; Over | Up to; Over | Up to; Over I4. 14. TA... | Eqs I4. Comparative Re- ligion Primary proposi- tions of chief re- ligious and philo- sophical interpre- tations of the world 0 : Td ~ - 3 3 Study of social types, .| General study of social structure associated with social types, = - - 2 2 leading to choice of réle to direct attention to choice of métier — — I 2 I made no reference to this part of the questionnaire. The one stating that Compara- tive Religion was taken added that it emerged from religious instruction. Another stated that Comparative Religion could only be taken with 17-18 group. The various questions discussed in the foregoing pages require further elucidation, for which more detailed investigation will be necessary. The Research Committee therefore suggest that permission should be given for the work to be continued during the coming year. SECTIONAL TRANSACTIONS. SECTION A. MATHEMATICAL AND PHYSICAL SCIENCES. Thursday, August 18. Symposium on Nuclear physics (10.0). Prof. N. Bonr.—Introduction. Due to the extreme facility of energy exchange between the closely packed particles in atomic nuclei, nuclear reactions show certain typical features which differ strikingly from those of ordinary atomic reactions. In particular nuclear transmutations initiated by collisions with heavy particles take place in two well-separated stages of which the first consists in the formation of a semi-stable compound nucleus, where the excitation energy is distributed among the nuclear particles in a similar way to that in a heated body, and the second in the subsequent disintegration of this system or its de-activation by emission of radiation, exhibiting instructive analogies to evaporation or thermal radiation respectively. Similarly the excitation of nuclei by radiation, resulting in the release of heavy particles, suggests a comparison with the well-known phenomena of selective ab- sorption of infra-red radiation by solid or liquid substances. It is shown how these views combined with simple arguments of quantum theory account in a comprehensive way for the experimental evidence regarding such nuclear phenomena. Prof. W. BorHe.—Some results concerning nuclear levels (10.45). The general outlines of the spectroscopic investigation of atomic nuclei are briefly given. Some new results are communicated and the following cases of special interest are dealt with in detail : (1) Resonance levels occurring with (n, «)-reactions. (2) Connection between the resonance levels in a case of branched reaction. (3) The nuclear photoelectric effect. (4) Nuclear levels occurring with the B-decay. Dr. J. D. CocxcrorT, F.R.S.—The High-Voltage Laboratory and Cyclotron of the Cavendish Laboratory and their application to nuclear research (11.30). The Cavendish Laboratory has recently extended its equipment for nuclear research by the building of a High Voltage Laboratory and a Cyclotron. The High Voltage Laboratory houses a 1:2 million volt D.c.. 382 SECTIONAL TRANSACTIONS.—A. generator, and a 2 million volt generator is being installed. ‘These genera- tors speed up streams of charged particles for use in transmutation experi- ments. The Cyclotron accelerates particles by giving them a succession of im- pulses as they move in the field of a powerful electromagnet. The magnet of the Cavendish equipment has pole pieces 90 cm. in diameter and should make possible the production of deuterons of energy up to 10 million volts. The Cyclotron seems likely to find its most important application in providing very strong sources of the new radioactive substances produced by transmutation. It also makes possible a much wider range of trans- mutations than can be produced by ions of only 2 million volts energy. The pD.c. generator, on the other hand, provides much more homogeneous beams of particles and is more suitable for precision work on the details of nuclear processes. Dr. P. I. Dee.—Excited states of light nuclei (11.45). Recent experimental work which has been carried out in the Cavendish High Voltage Laboratory has given evidence of the existence of many new excited states of certain light nuclei. ‘The bombardment of fluorine with artificially accelerated deuterons, for example, has been shown to result in the production of five homogeneous groups of «-particles, four of which may be associated with the formation of excited states of 17O nuclei. Evidence in support of the existence of these excited states of 17O has also been obtained by Dr. C. W. Gilbert from cloud track photographs of the disintegration of neon by fast neutrons. The energies of excitation of a number of other light nuclei have been determined by the investigation of the excitation functions of the y-rays which result from processes of proton capture. ‘The resonance character of the excitation of the y-radiation which results from the capture of pro- tons by carbon, for example, has been shown to be more complex than had previously been supposed. An intense production of y-rays at a proton energy of 560 K.V. has been proved to be due to the capture of protons by 18C, which results in the formation of excited 44N nuclei having an energy of excitation of about 8:o M.V. Dr. N. FEATHER. Some neutron-produced radioactivities (12.05). The radioactivities of various substances irradiated by the neutrons pro- duced by bombarding lithium by deuterons have been studied by a combina- tion of the absorption and coincidence methods, using tube counters. Information has been obtained regarding certain cases of nuclear isomerism and also regarding the long-lived products formed by bombarding thorium. The 6 and y radiations from a number of other radioelements have also been investigated. Dr. E. Bretscher and Mr. J. V. Dunworth have collaborated in the experi- mental work, and members of the personnel of the Cavendish High Voltage Laboratory have been responsible for carrying out the irradiations. GENERAL DISCUSSION (12.25) (continued on Friday afternoon). AFTERNOON. Wists to (a) Cavendish and Mond Laboratories; (b) Mathematical: Laboratory (for details see under Department A*). Film illustrating solar prominences. SECTIONAL TRANSACTIONS.—A. 383 Friday, August 19. PRESIDENTIAL AppRESS by Dr. C. G. Darwin, F.R.S., on Logic and probability in physics (10.0). (See p. 21.) Prof. H. SHapLtey.—Metagalactic gradients and the expanding universe hypothesis (11.20). The evidence for important metagalactic density gradients, which are of sufficient magnitude to invalidate the assumption of uniformity throughout the regions of space now attainable, is derived from surveys of the popula- tion and distribution of galaxies within a radius of over one hundred million light-years. The surveys cover extensive areas of the sky and display large-scale structural features of the metagalaxy. The character of the inner metagalaxy is demonstrated by the distribution of galaxies brighter than the thirteenth magnitude over the whole sky and by preliminary results on the distribution down to the fifteenth magnitude in the south galactic cap. The extension into southern declinations of the great cluster of bright galaxies in Virgo adds information on large-scale irregularity. Methods are shown of analysing distribution in both high and low galactic latitudes. Regions near the Milky Way plane, in which external galaxies are numerous, are studied for a determination of the extent of absorption within our own galactic system. Surveys involving 200,000 galaxies in the equatorial and galactic polar caps are presented. Density differences between the north and the south sides of the Milky Way are found to be considerable. ‘The radial gradient discussed by Hubble is compared with similar gradients across the sky, especially with that which is found to extend over 125° across the south galactic cap. This gradient presents such conspicuous density changes that it demonstrates the impossibility of using the observed distribution of galaxies to derive a coefficient of expansion of the universe. It is clear that such large-scale irregularities are an important feature of the metagalaxy and must be considered in cosmological theories. Prof. R. W. Woop.—Diffraction gratings for astrophysical purposes (12.0). Recent improvements in the technique of ruling gratings have made possible the concentration of 85 per cent. of the incident light in the first order spectrum, with a ruling of 15,000 lines to the inch. Two plane gratings ruled on 8-inch aluminised pyrex discs, one concentrating in the first, the other in the second order, are now in constant use in the spectro- graph of the 100-inch telescope at Mount Wilson, and have proved superior to prisms, especially in the ultra-violet. Measurements have been made, with a photronic cell and monochromatic light of various wave-lengths, showing the distribution of intensity for the central image and various orders, at different angles of incidence. The central image may contain as low as 1 per cent. of the total light. Large replicas have been made giving equally high concentration and these are being used at the Harvard Observatory for the determination of star colours, the grating, covered by a purple filter, being mounted a few inches in front of the photographic plate. A new attachment to the dividing engine makes possible the ruling of large concave gratings of very short focus with a groove of constant shape over the entire area, thus abolishing what I have called the ‘ target pattern ’ (circular zones of low efficiency). 384 SECTIONAL TRANSACTIONS.—A. Dr. H. E. Ives.—The rate of a moving atomic clock (12.30). According to the theory of Larmor and Lorentz, a moving clock should assume a slower rate than a stationary one. It was pointed out by Einstein in 1907 that the newly discovered Doppler effect in canal-rays offered a means of testing this prediction, but this test has been commonly considered as beyond experimental practicability. This objection has recently been removed, owing to the development by Dempster of a new design of canal- ray tube. The present investigation is an experimental test of the Larmor-Lorentz prediction, using these tubes. The hydrogen line 4861 A.U. has been used, observations being made by means of a plane grating of 15,000 lines to the inch, made by Professor R. W. Wood. The method of observation gave on one plate, the lines due to motion in opposite senses. ‘The experiment gave a positive result, showing shifts which are independent of the orienta- tion of the apparatus, and which agree, within the limits of experimental error, with the theoretical values. On the assumption of a stagnant ether, this experiment, with that of Kennedy and Thorndyke, establishes the reality of the Larmor-Lorentz variation of clock rate, and the Fitzgerald contraction. (CONCURRENTLY WITH ABOVE PAPERS.) Symposium on Magnetic alloys and X-ray structure (11.20). Prof. W. L. Brace, O.B.E., F.R.S.—Introduction. The magnetic properties of materials used for technical purposes have been improved in the most remarkable way in recent years. Better alloys have been discovered with a high permeability for small magnetising forces, or with low hysteresis loss when subjected to magnetic cycles, or with a high coercive force when used for permanent magnets. At the same time, the theory of magnetism has made rapid advances in the hands of the theoretical physicists, and X-ray methods of determining the atomic arrange- ment in these materials have been improved. The present position is very interesting because it is to be hoped that theory may now begin to play a part in technical achievement. In this introduction to the discussion a brief survey is made of the mag- netic properties of materials, and suggestions put forward as to the lines along which improvement may be expected. ; Dr. E. C. Stoner, F.R.S.—The general theory of ferromagnetism (11.40). In the Weiss treatment, which provides a qualitatively satisfactory formal correlation of many properties of ferromagnetics, it is postulated that the elementary magnets are acted on by a molecular field, equivalent in effect to a magnetic field proportional to the intensity of magnetisation. Such a field will give rise to spontaneous magnetisation below a critical tempera- ture, the Curie temperature, and to paramagnetic behaviour above it. The spontaneous magnetisation normally extends unidirectionally over only small regions, domains, and the effect of an external field is to align the directions of magnetisation of the domains. The elementary magnets in ferromagnetic metals are electron spins, and the molecular field has been satisfactorily interpreted as arising from quantum mechanical interchange interaction. The fundamental problems — SECTIONAL TRANSACTIONS.—A. 385 are those of accounting for the number of effective spins per atom, and the magnitude of the interchange interaction in different materials, and of developing a quantitatively satisfactory treatment of the temperature variation of magnetisation and related effects. Of most importance technologically is the behaviour of ferromagnetics in relatively low fields. The determinative factors for the sequence of reversible and irreversible processes occurring during magnetisation include the natural crystal anisotropy, the magnetostrictive properties of the material, and the distribution and magnitude of internal strains. Although a quali- tative interpretation can be given of the main effects, the development of a quantitative treatment for particular materials is as yet at an early stage. Dr. A. J. BRADLEY.—X-ray structure and ferromagnetism (12.10). Ferromagnetic alloys contain iron, cobalt or nickel (in the Heusler alloys, manganese). ‘They have crystal structures of a simple type :—face-centred cubic, body-centred cubic and (rarely) hexagonal close-packed. Of these types the body-centred cubic is the most favourable for the development of magnetic properties. Some non-magnetic alloys become magnetic when the structure is changed to body-centred cubic from another form. The materials used for permanent magnets (known as ‘ hard’ magnetic materials) must be distinguished from ‘ soft’ magnetic materials such as are used for transformer cores. ‘The latter have well-formed crystals, the structures of which are in no way abnormal. The former, though essentially of the same types (body-centred cubic and face-centred cubic), never have perfectly formed crystals. Some kind of strain is essential for the development of high coercive force. For example the alloy may be on the point of breaking up into two phases of different compositions. ‘The mechanism of this process may be such as to produce an intermediate metastable state. The alloy remains a permanent magnet so long as this state persists. Careful heat treatment is required to ensure that decom- position proceeds only to the point where the alloy has the best magnetic propetties. (Continued below). AFTERNOON. Symposium on Nuclear physics (continued from Thursday) (2.15). ' Prof. R. PErERLS.—Resonance in high energy reactions. Mr. S. Devons.—Resonance scattering of « particles. Prof. C. D. ELis, F.R.S.—Resonance levels in slow neutron processes. Dr. P. B. Moon.—A slow neutron velocity spectrometer. Prof. E. J. Witi1ams.—Loss of energy by fast particles in nuclear collisions. Dr. W. E. BurcHam.—Disintegration of fluorine by protons and deu- terons. Dr. M. GoLpHABER.—Radioactivity produced by nuclear excitation. 1e) 386 SECTIONAL TRANSACTIONS.—A. (CONCURRENTLY WITH ABOVE.) Symposium on Magnetic alloys and X-ray structure (continued) (2.15). Dr. W. SucksmitH.—The variation of magnetic saturation intensities with temperature in the iron-nickel-aluminium system. In view of the necessity for making measurements on a large number of alloys of widely varying physical properties, a new method of measuring the saturation intensity (in fields up to 18,000 gauss) from liquid air temperatures up to the Curie temperature, has been developed. The method requires only about 5th gram of the alloy, and is not dependent upon the shape of the specimen. The measurements are equally valid for materials ranging from coarse powders to roughly cut cylinders. Measurements have been made on alloys of which the X-ray structure has been investigated by Bradley and Taylor, the same specimens having been utilised through the collaboration of Dr. Bradley. Some of the multiphase regions have been investigated, and the results show that the phase boundaries as determined by magnetic methods con- form closely to those given by the X-ray data. The different regions usually have characteristic properties, and the effect of heat treatment upon struc- ture changes can be followed quite closely by observation of the magnetic saturation intensity at different temperatures. Mr. D. A. OLiver.—Martensitic permanent magnet steels and dis- persion-hardening alloys (2.45). The structures of martensitic permanent magnet steels and dispersion- hardening alloys are illustrated by a selection of photomicrographs. ‘The necessity for X-ray examination is stressed. A summary of the important magnetic properties is given with special reference to those alloys which are of commercial importance. The effect of impurities on magnetic proper- ties is discussed and recent data on the effect of carbon presented. Mention is also made of the improved magnetic properties which can be obtained when these magnetically hard alloys are cooled in a magnetic field. A few experiments are carried out illustrating either the properties or the applica- tions of the newer permanent magnet alloys. GENERAL DISCUSSION (3.15). Visit to works of Cambridge Instrument Company. Saturday, August 20. Symposium on High-altitude cosmic radiation (10.0). Prof. P. M. S. BLACKETT, F.R.S.—Introduction. Prof. W. H. Furry.—A discussion of some recent experiments on the properties of cosmic ray particles (10.45). It is now realised that most cosmic ray showers can be explained by the assumption that electrons multiply by radiative collisions and pair produc- tion as required by the present radiation theory. The most conclusive evidence comes from cloud chamber photographs obtained by Fussell. —— + o> SECTIONAL TRANSACTIONS.—A. 387 Three layers of lead in the chamber are spaced so that the successive stages of the multiplication process can be seen. Of two thousand showers photo- graphed, three were of a markedly different type, diverging from a point at more or less random angles and containing heavy particles ; these cannot be explained by the multiplication hypothesis. It has been known since the experiments of Bothe and Kolhérster and of Rossi that cosmic rays contain single corpuscles of much greater pene- trating power than the radiation theory allows for electrons. More detailed information about the penetrating power has been obtained by Street and Stevenson. Two cloud chambers are used; in one the momentum is measured by the curvature in a magnetic field, and in the second the pene- tration through layers of lead is observed. A number of particles are found which must be supposed to be neither electrons nor protons. Various observers have obtained tracks from which the mass could be estimated by the density of ionisation ; values obtained are about two hundred times the electron’s mass. Prof. W. BotHe.—New results in cosmic rays (11.30). Dr. E. J. Witt1ams.—The heavy electron (11.45). GENERAL DISCUSSION (12.0). Dr. R. W. Woop.—Crystal growth (film) (12.30). Dr. K. T. FiscHer.—The temperature coefficient of balances (12.45). AFTERNOON. Visit to the Observatory, Solar Physics eg aes Pendulum House, and Cavendish Field Laboratory. Monday, August 22. Discussion on Low-temperature physics, with special reference to Helium II (10.0). Dr. H. B. G. Casimir.—Introduction : Low temperature properties of matter. The problems of low temperature physics can be divided into two groups : those depending exclusively on the motion of atoms and molecules as a whole and those connected with the inner degrees of freedom of the atom. The study of electrons in metals and of paramagnetism are the two most important examples of this second group. In the limit of very low tem- peratures (T < 4° K) the properties of a non-conducting non-paramagnetic solid are comparatively simple. The heat motion can be described as a superposition of sound waves ; the specific heat is proportional to T* and can be calculated from the elastic constants. Also the theory of heat conduction becomes very simple. It is to be expected that at this limit the interaction between the lattice and the inner degrees of freedom will also be simplified. The theory of electrons in metals leads to the result that the resistance due to interaction with lattice vibrations decreases very rapidly (~'T®). In the case of para- magnetism, the lattice vibrations come into play only in so far as they must 388 SECTIONAL TRANSACTIONS.—A. establish the temperature equilibrium between spin and the surroundings ; the mechanism of this process is not completely understood. The case of HelII shows that in problems of the first group there are also interesting difficulties. Dr. J. F. ALLEN.—The properties of liquid Helium II (10.30). Liquid helium is a substance which differs most remarkably from any other liquid. The phase diagram of helium possesses no triple point for equilibrium between gas, liquid, and solid. Instead, as far as one can ascertain, the liquid phase persists down to the Absolute Zero, and the liquidus and solidus curves become parallel at that temperature. The liquid phase consists of two modifications, and the transformation between them occurs at 2:19° K (the A-point). The modifications, called HeI and Hell, are totally different phenomenologically. Hel is a normal liquid, while HelII possesses properties completely different from those of any other known substance. The most striking phenomena exhibited by Hell are as follows :—A negative temperature coefficient of expansion; a very high specific heat which suffers a discontinuity at the A-point ; a thermal conductivity which is approximately five hundred times as great as that of copper at room temperature ; and a mode of heat transport which appears to involve a transfer of momentum. When one measures the viscosity of Hell by means of a rotating disc, one obtains a value of 10-5 CGS units, i.e. comparable to a gas. On the other hand, when measured by the flow method the viscosity becomes immeasurably small and is certainly less than 101° CGS units. So far no comprehensive theory has been developed to explain all of the properties of Hell. Prof. J. H. VAN Vieck.—The molecular field and the determination of very low temperatures (11.15). In experiments on magnetic cooling, it is customary to determine the temperature by assuming that the susceptibility obeys Curie’s law x = C/T. Actually, this law cannot hold because of (a) the Stark splitting of energy levels caused by the crystalline fields from the non-magnetic atoms surround- ing the paramagnetic ion and (b) the dipole-dipole and perhaps exchange forces coupling together paramagnetic ions. The effect (a) is wanting in CsTi(SO,).12H,O, while (b) disappears at infinite magnetic dilution. Before reliable determinations of the temperature can be made from sus- ceptibility (in distinction from thermodynamic) measurements, it is necessary to devise an adequate theory of (a) and (b). Difficulties in the way of doing this, as well as the progress so far made, are summarised. In particular, the usual Lorentz field H + 4xM/3 is only an approximate representation of (b) valid only if the temperature is not too low. It is not even clear whether dipole-dipole forces can ever make a body become ferromagnetic. A discussion is included of the analogous electrical case, where possibly the hypothesis of hindered rotation may not be necessary to prevent spon- taneous polarisation in isotropic dielectrics. Ultimately, magnetic cooling experiments should throw considerable light on inter-molecular forces in the solid state. Dr. F. Simon.—Experiments below 1° abs. (11.45). The experiments carried out by Dr. Kurti, Dr. Lainé, Dr. Squire and the author with the magnet at Bellevue (Paris) are described. SECTIONAL TRANSACTIONS.—A. 389 The experiments were chiefly concerned with the study of the ‘ ferro- magnetic’ properties of iron-ammonium alum at very low temperatures, which were also extended to diluted salts and to an investigation in addi- tional fields. The reasons which may be responsible for this ‘ ferro- magnetism ’ are discussed. A new method for establishing temperatures on the absolute scale is described. DiscussION continued in afternoon (see below). Sir J. J. THomson, O.M., F.R.S.— Some recent experiments on electronic waves (12.15). (CONCURRENTLY WITH ABOVE SESSION.) Joint Discussion with Section G (Engineering) on Fundamental magnetic measurements with special reference to incremental con- ditions (10.0). (See under Section G.) AFTERNOON. Discussion on Low temperature physics (continued) (2.15). Dr. K. MENDELSSOHN.—Recent developments in superconductivtty. Dr. E. T. S. AppLeyarD.—The superconductivity of thin mercury films. Dr. H. Jones.—The superconductivity of alloys. Dr. N. Kurti.—Experiments below 1° absolute. Mr. E. S. Suire.—Paramagnetic relaxation below 1° absolute. Dr. H. B. G. Castmir.—Spin-lattice interaction. Mr. J. AsomEAD.—The production of intense magnetic fields for magnetic cooling experiments. Mr. J. G. Daunt.—New experiments on the transfer effect. Dr. H. Lonpon.—ZJnvestigation of liquid helium II by a Knudsen manometer. Dr. E. Ganz.—The thermal conductivity of liquid helium II under pressure. Mr. A. H. Cooxe.—The attainment of low temperatures by pumping off liquid helium. Mr. PickarD.—The construction of a standard expansion liquefier. Visit to works of British Tabulating Machine Co., Letchworth. 390 SECTIONAL TRANSACTIONS.—A. Tuesday, August 23. SYMPosIUM on Seismology (10.0). Dr. F. J. W. WuippLe.—Report of the Seismological Committee. Mr. J. S. Hucues and Miss E. F. Bettamy.—The International Seismological Summary (10.20). Prof. O. T. Jones, F.R.S.—Introduction to discussion (10.40). The purpose of the remarks is to emphasise the importance of seismo- logical studies in their application to purely geological problems. ‘Two such problems are of particular interest to Cambridge geologists, the depth of the Palzozoic floor and the course and depth of certain deep-buried channels, in particular that which runs through Chesterford and Newport, and has not hitherto been traced further. The Palzozoic floor is known directly only in borings, the nearest of which was about thirty miles from Cambridge. Dr. Bullard took up the determination of its depth by seismic methods, and an account of the results will be given by Mr. Gaskell. It is suggested that explosions made in quarrying may be utilised for similar purposes in many parts of the country. The investigation of the elastic properties of rocks is also of interest both to seismologists and geologists. The author suggested to Dr. Phillips the study of those of Coal Measure strata, and in the course of some brilliant work he obtained much more definite information about elastic after- working than had previously been obtained. The results may have an important bearing on the operation of stresses responsible for earthquakes and their aftershocks. If this is so it gives another illustration of the advantage of mutual co-operation between geologists and seismologists. Miss I, LEHMANN.—Characteristic seismograms at different distances (11.20). Dr. D. W. PuILiies.—Imperfections of elasticity in rocks (11.40). A study of the properties of Coal Measure rocks when subjected to different kinds of forces revealed considerable departure from truly elastic behaviour. Very many examples of sandstones, siltstones, mudstones, shales and coals have been subjected to examination in compression, bending and torsion. Both the longitudinal and lateral deformations were measured simul- taneously on cylinders of these rocks when subjected to compression. For the first two or three cycles of loading and unloading there was a progressively decreasing set, then for each succeeding cycle there was complete recovery of strain though the stress-strain curve always exhibited ‘ hyster- esis loop.’ There was a pronounced increase in both the longitudinal and lateral deformations when the load was maintained constant. At low loads the lateral time strain was small in comparison with the longitudinal time strain, but as the load increased the lateral time strain became equal to, and sometimes exceeded, the longitudinal time strain. Similar time effects were observed during unloading ; the strains removed immediately on the reduction of load were followed by a further gradual recovery. The elastic modulus and Poisson’s ratio usually increased with increase in the load applied. When subjected to bending these rocks required, as in compression, two / SECTIONAL TRANSACTIONS.—A. 391 or three cycles of loading and unloading to remove a set on no load. Further cycles resulted in complete recovery, with a hysteresis loop. Very pro- nounced increase in deformation took place when the load on the rock beams was maintained constant, and in some rocks these time strains increased with an increase of load up to a certain load, the time strain for higher loads progressively decreasing. In a few cases the further deformation with time had been allowed to progress until finally the beams fractured, some under loads which were less than the loads, applied without allowing time effect, necessary to fracture similar beams cut from the same rock samples. When subjected to torsion these rocks exhibited a time effect as in the case of compression and bending. Mr. T. F. GaskELL.—Seismic exploration of eastern England (12.0). The surface rocks of East England consist of Jurassic and Cretaceous clays and chalk. It has long been known that these are underlain by a planed-off surface of Palzozoic rocks, but the depth of this surface was only known at a few isolated points. The refraction methed of seismic pro- specting has been applied to map this surface. Charges of gelignite up to 15 lb. are used to make impulses in the ground, and six electrical seismo- graphs record the arrival of the waves produced. The recording apparatus is transported in a van, and depths of the Palzozoic have been determined at stations distributed over a large area of Eastern England. AFTERNOON. Symposium on Seismology (continued) (2.20). Dr. H. Jerrreys, F.R.S.—Deep foci and aftershocks. The work done by Dr. Phillips throws light on some difficult seismological questions. Two hypotheses concerning the mechanical properties of rocks are that of a finite viscosity at small stresses, or zero strength, and that of an infinite viscosity at small stresses, or finite strength; the former is associated most prominently with the name of Wegener, the latter with that of Barrell. The latter agrees better with the distribution of gravity anomalies, and with the fact that stresses capable of producing major earth- quakes can develop at depths down to about 700 km. It has not, however, been easy to see how the idea of perfect elasticity up to a definite limiting stress can be reconciled with the existence of aftershocks continuing for months after the main shock. Dr. Phillips’s work shows how this can be done, by the recognition of the distinction between the stress that leads to immediate fracture and that which leads to fracture only if it is left on long enough. The intensive study of deep focus earthquakes is likely to lead to solutions of some difficult seismological problems that are almost insoluble from the data of normal shocks, namely the depth of the core, the nature of, the 20° discontinuity, and the times of the transverse wave up to distances of about 25°. Dr. R. STONELEY, F.R.S.—Times of travel of the L phase (2.50). It was found by Prof. H. H. Turner that L readings given by stations have travel times equivalent to 0-48 min./degree, but that sometimes onsets corresponding to 0:41 min./degree predominate. The former correspond 392 SECTIONAL TRANSACTIONS .—A, A*. to the arrival of long Rayleigh waves, the latter to long Love waves. An analysis of a number of earthquakes listed in the J.S.S. shows a marked separation of the L readings into two groups, with travel-times clustering round the above values. The relative proportions of the two types suggest intrinsic differences in the dislocations that initiate the waves. Differences are shown for earthquakes in the same region, so that the effect cannot be attributed entirely to the distribution of stations or of land and sea. To ascertain the dependence on intensity of shock a reliable measure of in- tensity would be needed. Prof. J. D. Bernat, F.R.S.—Crystallographic relations of seismology (3.10). A possible explanation of the 20° discontinuity is to be found in the hypothetical existence at lower levels of the earth’s crust of a denser and more elastic crystal form of olivine (MgFe),SiO,. Such a form has never been observed owing to the impossibility of producing sufficiently high pressure, but it might be expected that the condition of silicates at high pressure should be shown by germanates at ordinary pressures, owing to the greater size of the germanium ion. Magnesium germanate has been observed to exist both in olivine structure and in the cubic spinel type of structure. A calculation based on this structure would seem to be able to account in a rough quantitative way for the properties required for the ' substances at low levels. DEPARTMENT OF MATHEMATICS (A*). Thursday, August 18. SyMposiuM on Newtonian root evaluations (10.0). Chairman: Dr. J. WIsHaRT. Prof. A. OstRowsk1.—On Newton’s method of approximation (10.0). To compare the amount of work in Newton’s method of approximation for a root € of the equation f(z) = o with the effect of the method, a unit of the calculatory work is introduced—a Horner, that is the work of calculating the value of f(z), this unit being assumed as sensibly independent of vy and the number of digits in z. On the other hand, the rate of the approximation of € by y is measured by the order of | y — €], if the initial value x, tends to%, the order of |x, — C| being assumed as 1. Newton’s method gives with 6 Horners an approximation of the order 8. A modification of Newton’s method is proposed allowing to obtain with’ 6 Horners an approximation of the order 16. It consists in using alternately the two formule : I (xo) ‘4 ; F(xy)(%1 = Xo) anita eee ye oe 2iCai= Leas Prof. E. H. NevitLe—Computational labour in modifications of Newton’s method of approximation (10.30). The processes of interpolation have been developed on the assumption that the arguments for which they are to be used may be anywhere in the SECTIONAL TRANSACTIONS.—A*. 393 interval between consecutive tabular entries. Root-extraction, treated otherwise than as inverse interpolation, is a step-by-step determination of a sequence x), X2,%3,... To obtain xn+, from xj, Xs, ... ,Xnand functional values at these points by inverse interpolation of the ordinary kind is to ignore the possibility of profiting from the circumstance that Xy+ , is much nearer to x, than to x;-,; on the other hand, in Newton’s formula and in any slight modification of it, the labour of each step is apt to be considerably greater than the labour of a linear interpolation, and since we determine x» +, from x» only, we are continually abandoning information which we have been at pains to acquire. We need not balance disadvan- tages: Prof. Ostrowski’s method is one compromise which retains some of the advantages of each extreme; another, simpler and in the long run more efficient, is the recurrent use of the one formula (mn, n— — Mn—1,n—2)VnYn—1 Kn. = Xn — Mn, n— 10 + ST TT PT NC (Os pape td gee a | where r,s = (xr — Xs)/(yr — ys). Mr. D. H. SapLer.—The estimation of computational labour (10.40). The difficulties of absolute estimation are summarised, and the care that must be taken in forming relative estimates is stressed. Illustrations are given in the simple case of computing a polynomial expression. Symposium on Combinatorial mathematics in the design of experiments REr10). Chairman: Prof. R. A. FisHer, F.R.S. Dr. C. C. Cratc.—Some remarks on randomisation (11.10). The usefulness and validity from the point of view of fiducial probability of significance tests based on the principle of randomisation is well recog- nised. However, it seems of some interest to the author to illustrate how the effectiveness of such a test may depend on the populations from which, in fact, the samples were drawn. In particular, suppose two samples of N are drawn, one from each of two normal populations with equal variances but unequal means. By sampling methods, the probability that the test based on randomisation will indicate that the population means differ is studied. Mr. H. W. Norton.—The 7 x 7 Latin squares (11.30). A discussion of 7 Xx 7 Latin squares leading to Greco-Latin squares, and of the enumeration of the 7 x 7 Latin squares. Dr. W. J. YoupEN.—Complex square designs in plant physiology and their connection with incomplete randomised blocks (11.50). In recent years the use of experimental designs based on the combina- torial properties of numbers has been developed in plant physiology and pathology as in other fields. The natural structure of experimental plants makes it desirable to eliminate causes of variation due both to the indi- viduality of plants, and to leaf order, using a double elimination as in the Latin Square. In addition the principle of balanced incomplete blocks is 02 394 SECTIONAL TRANSACTIONS.—A*. needed owing to the limited number of leaves. A group of designs com- bining the two qualities, and which have proved useful in practice, is exhibited. ‘The remaining unsolved combinatorial problems are indicated. Mr. F. Yates.—The use of lattice squares in plant improvement (12.10). Efficient methods of comparing, under field conditions, large numbers of new varieties produced by genetical segregation are a vital need in prac- tical plant improvement. ‘The new quasi-factorial and allied designs give methods of considerably increasing the accuracy of the field comparisons, using the same amount of experimental material, and supersede the older methods of arrangement, such as the use of ‘ control’ varieties. Many of these designs depend on the existence of Greco-Latin and higher order orthogonal squares, and the question of the existence of such squares, first investigated by Euler, has therefore become of practical importance. In particular the existence of complete sets of orthogonal squares is necessary for the construction of designs in lattice squares (which enable p? varieties to be arranged in squares of side p, eliminating fertility differences between rows and between columns) and for the construction of certain types of incomplete randomised blocks (i.e. randomised blocks each of which con- tains only a proportion of all the varieties to be compared). Mr. W. L. STEvENs.—Completely orthogonalised squares (12.30). It is known that for certain values of p, (p — 1) Latin squares may be formed such that any two of the squares are mutually orthogonal. Solutions are now known for p = 2, 3, 4, 5, 7, 8, 9, and any prime number. It is believed that a solution exists when p is any power of a prime. The case proved is for the square of any prime, and the theory has been applied to develop a completely orthogonalised square of side 25. AFTERNOON. Visit to the Mathematical Laboratory. Symposium and Demonstration on Mechanical methods of computation (3.0). Prof. J. E. LENNARD-JONES, F.R.S.—Bush differential analyser. Mr. M. V. Witks.—Mallock machine (3.20). Demonstration of Bush and Mallock machines (3.30). Dr. J. WisHart and Mr. D. H. SapLer.—Description and demonstration of Hollerith and National machines (4.45). Friday, August 19. Symposium on From function to printed table : some aspects of the work of preparing a table of a mathematical function (11.30). Chairman: Prof. E. H. NEVILLE. Dr. W. G. BicKLEY.—Computation from series and by recurrence formule. Some elementary considerations concerning computation by power series, especially with regard to labour saving and checking, are discussed. For greater values of the argument, convergence of the power series is SECTIONAL TRANSACTIONS.—A*. 395 delayed, and asymptotic series must be used. In straightforward applica- tion, the accuracy is definitely limited by the size of the smallest term. Two means of increasing the accuracy, the Euler transformation and the convergence factor, are described. Recurrence formulz are very useful, but they usually lose accuracy when used in one direction. This fact can upon occasion be turned to advantage. Two outstanding difficulties, with some slowly convergent series, and with asymptotic series whose terms are all of the same sign, remain. Dr. J. C. P. MILLer.—Step-by-step integration of a differential equation, with some remarks on interpolation (12.0). Expansions in series, whether convergent or divergent, are often incon- venient for the systematic tabulation of a solution of a differential equation for some ranges of the argument, although they are indispensable as checks. Hence, in order to compute pivotal values, i.e. values which form a basis for subsequent subtabulation, we frequently use step-by-step pro- cesses over some part of the range. Two such processes are briefly de- scribed, namely the Double Summation and Taylor Series methods, as applied to certain second order equations. Methods of checking and ways of estimating and minimising cumulative errors, as well as the application of the Taylor Series method to interpolation, are also considered. Dr. A. J. THompson.—The printing of mathematical tables (12.30). The paper describes the several processes that come between the com- pletion of the calculation of a mathematical table and its appearance as a printed volume. Jnter alia, it deals with the preparation of the printer’s copy, with typographic details (such as choice of type, spacing and rules) and with the methods of ensuring accuracy. ‘The standpoint is that of the computer of the table, and technical matter is reduced to a minimum. The paper is illustrated by photographs of a number of tables. Monday, August 22. Prof. G. D. BirkHorr.—Analytic deformations (10.0). Prof. S. LerscHetz.—Fixed points of transformations (11.15). The author first points out by examples the réle of the problem in various mathematical disciplines. If the elements transformed are points of an abstract space R we are dealing with a problem in_ topology. Suppose that we have a transformation T of R into itself. Under certain very general conditions (C) if 'T is a transformation of R into itself there may be given a topological character 9 (T) having the property that when 80 there is at least one fixed point. Conditions (C) embrace con- tinuous single-valued transformations of a polyhedron into itself, and more generally of a very broad class of locally connected spaces (absolute neigh- bourhood retracts when R is compact metric). Special noteworthy case : R is the Hilbert parallelotope. For all these cases an explicit expression of @ may be given in terms of the transformations which T induces on the cycles of the space. 396 SECTIONAL TRANSACTIONS.—A*, Prof. W. V. D. Hopce, F.R.S.—Some applications of harmonic integrals (12.0). On an analytic variety which is an absolute orientable manifold a p-fold integral which is exact has the property that its value taken over a bounding p-cycle is zero, but it may have a non-zero value when taken over a p-cycle which is not homologous to zero; this we call the period of the integral on the cycle. It is known that if Ry» is the pth Betti number of the manifold there exist exact integrals which have arbitrarily assigned periods on Rp independent p-cycles. If the manifold carries a Riemannian metric gigdx'dxi we can associate with a p-fold integral Al Pi... gd... dts (x) an (n — p)-fold integral TG Ci, oss ipfy ee «jap... giro Ph... kpdxhi ... dxivw (2) If the integrals (1) and (2) are both exact we say that (1) is a harmonic integral. It follows that (2) is also harmonic. It is known that there exists exactly one p-fold harmonic integral having assigned periods on Rg in- dependent p-cycles of the manifold. In a mathematical theory in which an analytic manifold appears it is often possible to assign a Riemannian metric to the manifold in such a way that the harmonic integrals prove useful weapons in the development of the theory. Dr. B. KAuFMANN.—Topological methods in the theory of conformal repre- sentation (12.45). In the theory of conformal representation there are two main groups of problems: the ‘inner’ problems concerning mappings of plane regions, and the problems on boundary relations. The most important result in the first group is Riemann’s fundamental theorem, and in the second Fatou’s theorem. The development of the theory in these two directions has led to two well-known topological conceptions : the Riemann surface, and ideal elements (prime ends). Through Hilbert’s work at the beginning of this century it became possible to extend the inner mapping theorems to regions of arbitrary connectivity (Hilbert, Kébe). But the boundary problems in the general case remained unsolved. However, the general theory of ideal elements makes it possible to approach these problems. The existence as well as the nature and the structure of the ideal elements is revealed by a close study of a certain o-dimensional group of limit cycles in an n-dimensional region by methods of an appropriate homology theory. This group can be turned into a certain abstract space in which the ideal elements can be seen and described. With the help of a method of canonical dissections of regions of infinite connectivity (which might be called Souslin dissections) some first results on boundary relations are obtained. These ultimate results can be understood without any knowledge of the theory of ideal elements. AFTERNOON. Visit to works of British Tabulating Machine Co., Letchworth. SECTIONAL TRANSACTIONS.—A*. 397 Tuesday, August 23. Prof. A. SpEIseER.—Elliptic functions from an elementary standpoint (10.0). It is a well-known theorem, that a simply connected Riemann surface may be transformed conformally on the Euclidean plane or on the interior of a circle. With the aid of this fact it is proved that the general theory of elliptic integrals consists ultimately in the possibility of paving the plane with congruent quadrilaterals of any shape. Dr. B. H. NeumMaNN.—General decompositions of groups (10.30). A group G is said to be the general product of its sub-groups A and B whenever (i) A. B=G;; (ii) AQ B= {1}. Aand B are called general factors or complementary sub-groups. In the special case, when both factors are self-conjugate in G, we have the well-known direct product. The following problems have been attacked, the first with a view to applications in geometry : (i) Given G and a sub-group A ; to decide whether A is a general factor of G and to find complementary factors. (ii) To characterise the groups in which certain types of sub-groups (e.g. the Sylow sub-groups, or all sub-groups) are general factors (P. Hall). (iii) Given A and B, to find their general products. However, much,remains to be done, specially as regards the third problem. Mr. P. Hatt.—The verbal classification of groups (11.15). Let f(x,, . . ., Xn) be any word, G any group, V = V;(G) that sub-group of G which is generated by. all elements of the form f(a,, . . ., an), where the a’s are arbitrary elements of G. Let W = W;(G) be the (unique) greatest self-conjugate sub-group of G with the property that f(qhi, ns -» Anbn) = f(a, « « +5 an) for every choice of a’s in G and b’s in W. ‘Then, if V’ and W’ are the corresponding sub-groups of another group G’, the latter is said to be isological with G (in respect of f) if there exists between G/W and G’/W’ an isomorphism, aW-—>a’W’, such that the correspondence f(a, .. +, Qn) >f(a’}, ... a’n) determines an isomorphism between Vand V’. This relation of isologism between groups has the properties of equivalence, and separates all groups into a number of mutually exclusive families in respect of their behaviour as regards the given word f. By choosing a different word in place of f, we obtain (in general) a different classification. ‘The most interesting choice is to take f= x,-1x,.7-1x,x_. This gives the commutatorial classification, which is especially appropriate for the discussion of prime-power groups. In this case, V is the derived group, W the central, and isological groups have many numerical invariants in common. Dr. Otca Taussky.—Dzifferential equations and hypercomplex systems (11.45). It is known that each of a pair of functions satisfying the Cauchy-Riemann equations satisfies the Laplace equation. Similarly for each of a set of four functions satisfying the Dirac equations. It can be shown that the same 398 SECTIONAL TRANSACTIONS.—A*. holds for each of a set of eight functions satisfying a certain set of eight linear differential equations. Let J; = cng ,(@=1,..., ”), bem linear differential forms with con- a stant coefficients such that Su; 82; 5 : Sat to it sa ai gory + ++. + ange ly tS ae where the ajz are constants and the 7% any of the numbers 1,...,”. The numbers n for which such relations exist can be completely determined by properties of (not necessarily associative) hypercomplex systems over the real numbers. The best known non-associative hypercomplex system— the Cayley numbers—is closely connected with the set of eight linear differential equations mentioned above. Laplace’s operators in two and four variables are special cases of a class of differential operators which are connected in the following way with hyper- complex systems over the real numbers. Let S be a hypercomplex system with 2 base elements @, . . ., én and let xje, + ... + Xnén be a general element of SS, where the x; are any real numbers. The norm of x,e, + . + xneén, if defined by means of the regular representation of S, is a homogeneous function f(x,, . . ., Xn) of the mth degree in x1, . . ., Xn. If the co-ordinates are replaced by the differential operators 5x? Sa 2 1 n differential operator i(., hepa dtas s) is obtained. Let S be the system 8x, 8xn of complex numbers or of quaternions. The operator which is so obtained is Laplace’s operator. Mr. GarrETT BIRKHOFF.—Laittice forms (12.15). d Wednesday, August 24. Mr. J. H. C. WuiTEHEAD.—A generalisation of groups (10.0). The starting point is the equivalence of simplicial complexes under three kinds of elementary transformations and their inverses. The first are elementary sub-divisions, giving combinatorial equivalence. The second are of the form K-— K + aA, where aA, but not aA or A, belongs to K, A and aA being k- and (k + 1)- simplexes for an arbitrary value of k, and A being the boundary of A. The third consists of these, together ‘with transformations of the form K—> K + A, where A, but not A, belongs to K, and the dimensionality of the simplex A exceeds some fixed m, which may be arbitrarily chosen in the first place. Complexes which are equiva- lent under the second and third kind are said to have the same nucleus and the same m-group respectively. The justification for the term m-group lies in the theorem that two complexes have the same fundamental group if, and only if, they have the same 2-group. The m-group of a complex is seen to be a topological invariant, for each value of m, and the nucleus is a topo- logical invariant provided the fundamental group satisfies a certain condition, which is stated in terms of the ‘integral group-ring.’ An immediaté application is that certain invariants discovered by K. Reidemeister, and shown by him to be combinatorial invariants, are actually topological SECTIONAL TRANSACTIONS.—A%*, B. 399 invariants of a complex. This completes not only the combinatorial, but also the topological classification of lens spaces. Dr. S. EILENBERG.—On continuous mapping into spheres (11.15). Let MM" be a finite or infinite simplicial, orientable, n-dimensional mani- fold ; XcM" a closed and compact sub-set of M” and P*cM* — Xa closed (finite or infinite) k-dimensional sub-polyhedron of M”. For each k-dimen- sional simplex a? of P?, let s?~*~* be an (mn — k — 1)-dimensional spherical manifold, contained in M* — X — P* and ‘ simply linked ’ with a’. Given a continuous mapping f, of M” — P* into an m-dimensional spherical manifold S”, the mapping f(st* cS determines a unique element «(f) of the (n — k — 1)th homotopy group tn—p—-1(S”"), of S”. We write Y*(f) = Laalfaf, summed for all the k-dimensional simplexes of P*. (I) y*(f) is a k-dimensional (finite or infinite) cycle in P*, with coeffi- cients from the group T——1 (S”). (II) If y*(f) is homologous to zero in M”"— X, there exists a (k — 1)- dimensional closed sub-polyhedron P*—?cM” — X, of M™, and a continuous mapping f*(M” — P*—t)cS” such that f(x) = f*(x) for each xeX. An application: consider in S” two disjunct sets Sy’ and S?~”", homeomorphic with S” and S"—”~—* respectively. S7' is called a retract of S* — S?~”* if there exists a continuous mapping f(S” — S}~-” *)cST such that f(x) = x for each xe ST’. (III) S7 is a retract of S” — S}-”* if, and only if, the linking coefh- cient of S?” and S?~”~* is + 1 (according to the orientations). Prof. M. FrécHet.—Hilbert space (11.45). SECTION B.—CHEMISTRY. Thursday, August 18. INTRODUCTION by Prof. Sir W1LL1aM J. Pore, K.B.E., F.R.S. (10.0). PRESIDENTIAL ApprESss by Prof. C. S. Gipson, O.B.E., F.R.S., on Recent advances in the chemistry of gold. (See p. 35.) Discussion on Recent advances in the organic chemistry of the metals, with special reference to the noble metals. (Exhibition) (11.15). Dr. F. G. Mann.—/Introduction. Prof. L. O. Brockway (12.0). 400 SECTIONAL 'TRANSACTIONS.—B. Prof. N. V. Sipewick, C.B.E., F.R.S. (12.20). GENERAL DISCUSSION. AFTERNOON. Visit to the works of the Cambridge Instrument Company. Prof. C. S. Gipson, O.B.E., F.R.S.; assisted by Dr. F. G. Mann, Mr. H. V. THompson and Dr. F. H. Bratn.—Demonstration in Section B lecture room on the production of gold films by chemical methods (5.15). During 1856, Faraday was occupied in determining the experimental conditions for the production of thin metallic, chiefly gold, films with a view to the investigation of their optical properties. ‘This work had important consequences in other directions and Faraday refers to ‘ this long and as yet nearly fruitless set of experiments on gold ’ probably because he was not successful in producing gold films to his own satisfaction. It is interesting, however, that Faraday appears to foreshadow the modern method of pro- ducing films of gold and other metals by the ‘ sputtering ’ process. The demonstration is concerned with some methods of the production of gold films and their application in the arts. The application of gold films to surfaces of glass and porcelain has long been known and the pro- duction of gold mirrors—having magical properties and being the criteria of excellence—whether of glass to which beaten gold was applied mechani- cally or of polished alloy was known to the early Chinese, Egyptians, Greeks and Romans. A recipe for the production of a golden mirror is given by Geber. The application of gold films to ceramics is described and demon- strated as far as possible by Mr. H. V. Thompson, M.A., with the collabora- tion of Mr. Bernard Moore and Messrs. Colclough China, Ltd., of Stoke- on-Trent. Dr. F. G. Mann shows the production of gold films on glass by the action of heat on the trialkylphosphineaurous halides which he has recently described. Prof. C. 8. Gibson, F.R.S., and Dr. F. H. Brain demonstrate the production of gold films by the decomposition of organic gold compounds at the ordinary temperature and indicate their application in the arts especially as mirrors and for decorative purposes by a number of specimens. Friday, August 19. SyMposiuM on Modern methods of chemical analysis (Exhibition) (10.0). Dr. J. J. Fox, C.B., O.B.E.—Jntroduction. The requirements of analytical chemistry are now so extensive, that the older methods have had to be revised and extended in many directions. Particularly the development of methods of micro- and semi-micro-methods has attracted workers all over the world. It is not too much to state that these methods, and their accuracy, have rendered possible investigations which could not have been carried out without them. An important advance in analytical methods arises from the extending utilisation of physical processes. These have resulted in advance in two directions, namely, accuracy and speed of analysis. For example, the use of spectro- - graphic methods renders it possible to examine alloys of various kinds with speed and sufficient accuracy for many industrial processes. Further, the SECTIONAL TRANSACTIONS.—B. 401 spectrographic method is available especially for the determination of minute quantities of various elements in biochemical, agricultural, and general chemical analysis. More recently we have utilised infra-red spectroscopy in such determinations as the proportions of o- and p-hydroxy- diphenyl sometimes found present in traces in synthetic phenol. For the purposes of demonstration two methods, now much used in our laboratory, have been chosen. The first is the determination of moisture by means of the variation in the dielectric constant. This method is particularly suitable when large numbers of similar products, e.g., cereal powders, have to be examined for moisture. The apparatus must be calibrated for each kind of material and with suitably devised cells deter- minations can be made readily in a few minutes, thus enabling products to be sorted out rapidly. Extension of the method to liquids is obvious and apparatus is on the market for the purpose. It should be noted that the usual form of apparatus fails when the moisture is high and electrolytes are present. A second method is the polarographic method associated with the name of Heyrovsky. An apparatus has been devised whereby the curves are plotted by means of a recording pen, thus dispensing with the necessity for visual or photographic recording. It must be stressed that in work of this kind calibration of the apparatus is essential for the problem in hand. This applies equally to many other physical methods, e.g. colorimetric. and nephelometric determinations. Prof. WALTHER GERLACH.—Spectrochemical analysis with special reference to biological preparations (Demonstration) (10.30). Prof. Fritz Fe1cL.—Inorganic and organic spot-analysis (Demonstra- tion) (11.15). The so-called spot-analysis is a microchemical technique of qualitative analysis ; it consists in the application of highly sensitive reactions to the detection of inorganic and organic compounds in one drop of solution or with traces of the solid substance. Such spot tests are carried out by mixing one drop of the solution and one drop of the reagent on filter paper or in small crucibles or on the so-called spot plates. Filter papers which are impregnated with the particular reagent are very useful. The special apparatus required is very simple. By means of spot analysis it is possible to carry out specific detections on minute amounts of material and to recognise quantities down to fractions of a millionth of a gram. The saving in material, time and work is the predominating characteristic of spot analysis. The right choice of suitable reactions is of importance. Only such reactions as are sensitive and specific are used. Therefore the theory of spot analysis is bound up with the chemistry of so-called specific reactions and with all measures whereby sensitivity can be increased. Of great importance are the application of organic reagents, the employment of catalysis and the use of colloidal and capillary phenomena. The formation of fluorescent compounds is also used. Dr. JANET MatTHEws.—Microanalysis (11.35). Inorganic micro-methods of quantitative analysis are now sufficiently developed to warrant their adoption in both research and technical problems. The filter stick technique has been successfully used already in problems of plant nutrition in growth experiments with barley. Without the use of 402 SECTIONAL TRANSACTIONS.—B. micro-methods the research would have entailed the growth and drying of so much plant material as to render it quite unfeasible; nitrate, potash, phosphate, calcium, magnesium and approximate silica were determined in about 200 samples, which on the macro scale would have involved enormously increased labour. : Another application of micro-methods actively in progress is in the analysis of dust, especially in connection with work on silicosis and allied diseases caused by the inhalation of dangerous dusts. Micro-methods enable a quantitative gravimetric analysis to be carried out on a total of about 50 mgm. of material, the analyses including silica, iron, alumina, calcium, magnesium, sodium, potassium and loss on ignition. The methods are also capable of application in the cement and glass industries, the paper industry and many other industries, and preliminary work on some of these applications is at present in progress. This shows that a trained analyst can learn micro-methods extremely rapidly and in the first week of work attain, for example, figures for silica in glass with errors of less than + o-1 per cent. difference from the calculated value. A brief description is given of methods for the determination of silica, iron, sulphate, phosphate and nitrate which are found to give good results on the micro-scale. _Dr. H. Jackson.—Technique of hydrogenation (Demonstration) (11.55). A short survey is given of various types of apparatus which have been devised during the past few years for the accurate micro-estimation of the degree of unsaturation of organic compounds, together with a more detailed account and demonstration of the technique used in a particular form of apparatus. This is followed by a description and demonstration of the application of the technique to the construction of an all glass, quantitative system functioning at atmospheric pressure, which is designed to cover all ordinary laboratory requirements. Dr. K. K. Nycaarp and Dr. Tu. GutHe.— Application of the photo- electric principle to the determination of ascorbic acid (12.5). By the use of an original, previously described apparatus termed the Photelgraph, the authors have succeeded in automatically recording, by the photo-electric principle, various processes in which a relative change in trans-illumination of the specimen occurs during the process. (Coagula- tion of blood ; The Wassermann reaction.) This principle has been applied to a study of the well-known specific reduction of a solution of methylene-blue under the influence of artificial light in the presence of ascorbic acid. Under standardised conditions this process is quantitative as concerns each of the three main factors participat- ing in this photo-chemical process. The present method records automatically and graphically on photo- sensitive paper the degree of reduction taking place. With constant, known values of the artificial light, exposing methylene- blue solution of known, constant concentration, the geometric appearance of the tracing obtained indicates indirectly the quantity of the third and variable factor, the ascorbic acid. This quantity expressed in micro- grams. per cm® of solution is obtained by comparison of the tracing with that of a solution containing a known concentration of ascorbic acid. By this method it has been possible to determine quantities less than 005 microgram of ascorbic acid per 100 cm? of solution. GENERAL DISCUSSION (12.20). SECTIONAL TRANSACTIONS.—B. 403 AFTERNOON. Visit to the University Departments of Chemistry and Metallurgy. Monday, August 22. Discussion on Clays (10.0). Chairman : Prof. E. K. Rrpeat, M.B.E., F.R.S. Prof. W. L. Brace, F.R.S.—General features of the atomic structure of silicates : inferences to be drawn from them as to the structure of clay minerals. The minerals found in clay are often of very variable chemical constitu- tion, and are imperfectly crystallised. ‘The evidence as to atomic pattern given by X-ray diffraction is meagre and difficult to interpret. It is there- fore necessary to supplement it by making use of all the knowledge we have about the grouping of atoms in silicates in general, which has been obtained by studying well-crystallised types. The silicon-oxygen framework of a silicate, composed of tetrahedral groups linked by their corners, is so rigid and strong that it determines the form of the whole structure. In most, if not all, clay structures, the framework takes the form of sheets of tetrahedra linked by their bases, with free vertices. Such sheets are found in mica, which has been analysed completely. Here they occur in pairs, with vertices opposite each other and linked by aluminium or magnesium atoms, so as to form a strong double sheet. In certain other minerals the sheets are single. Such sheets may either be directly superimposed in the mineral, or be separated by intermediate layers containing ions, or water molecules. The physical chemistry of the clays is bound up with the attachment to the sheets, or detachment from the sheets, of ions and molecules. In making hypotheses about the behaviour of clay, one must bear in mind the general principles concerning atomic situations and replacement which have emerged from the study of silicates of all kinds. These will be briefly summarised. Dr. G. Nacetscumipt.—Structure and properties of imperfectly crystallised clay minerals (10.20). According to their power to diffract X-rays two groups of clay minerals can be distinguished. 'The minerals of the first group show more perfect crystallisation and give better developed powder diagrams than the minerals of the second group. The first group includes kaolinite and pyrophyllite, and the second group halloysite and montmorillonite. The atomic arrangements in the second group are mainly derived by analogies and require further confirmation. Montmorillonite is taken as example of the second, imperfectly crystal- lised group, and its chemical variations are described as isomorphous substitutions within the lattice. These substitutions lead to negative charges, which are compensated by excess cations. The bulk of the excess cations is exchangeable. Montmorillonite shows reversible one-dimen- sional lattice shrinkage and expansion upon variations in water content. The amount of water held in equilibrium depends on the vapour pressure, and, at a given vapour pressure, on the kind of excess cations present. 404 SECTIONAL TRANSACTIONS.—B. The study of the structure and properties of these minerals is important for the understanding and control of many processes in the ceramic and bleaching industries, and in soil management. DISCUSSION (10.40). Dr. R. K, ScHoFIELD.—Origin of the electric charges on clay particles (11.10). ; Clay particles are generally electrically charged and therefore retain an equivalent quantity of ions which can only be removed by exchange with other ions carrying the same charge. Exchange of ions is of great import- ance in the industrial handling of clay and in land reclamation. Some of the charge on clay particles is due to isomorphous substitutions within the crystal lattice and is permanent in the sense that it is not in- fluenced by the hydrogen ion concentration of the medium in which the clay is suspended. ‘There are also ‘ spots’ on the particles which are charged or uncharged according to the reaction of the medium. They are of two kinds: acidic spots where negative charges can develop through the dissociation of hydrogen ions, and basic spots where positive charges can develop through the combination of hydrogen ions. The process in the case of the acidity spots is probably >Si—OH = >Si—O +Ht the silicon atoms being those situated at the edges of the silicon oxygen sheets. The chemical nature of the basic spots is uncertain. ‘They are not found in the clay minerals so far identified but are frequent in the common clays. The equilibrium is possibly + — Al—OH 2 —Al=O+Ht and may be due to an over-crowding in the ‘ gibbsite ’ layer. A study of the variation of the electric charge with pH enables the amounts of permanent charge and of the acidic and basic groups to be determined. Approximate values have also been obtained for the dissocia- tion constants of the groups concerned. In certain clays the number of basic groups exceeds that of the permanent (negative) charges. These exhibit well-defined isoelectric points. Prof. J. D. BERNAL, F.R.S.—The hydroxyl bond in clay minerals (11.30). The essential process that takes place in the formation of clays from rock minerals such as felspar or mica is hydration. In the first stages, however, water does not form part of the clay as such, but as hydroxyl groups bound to magnesium, aluminium, or more rarely silicon ions. A hydroxyl group bound to one of these ions is capable of attaching itself to other hydroxyl or oxygen atoms in neighbouring layers owing to the polarising power of the hydrogen it contains. The strength of the hydroxyl bond thus formed depends on the charge of the ion to which the oxygen atoms are attached. It is strongest for a silicon, weakest for a magnesium ion, and this is also the order of the capacity to lose the hydrogen ion altogether or the order of decreasing acidity of the clay particle. In greater degrees of hydration water molecules are bound to the hydroxyl group, but in a way which resembles the structure of ice more than it does that of free water, owing to the directing effect of the hydroxyls. GENERAL DISCUSSION (11.50). SECTIONAL TRANSACTIONS.—B. 405 AFTERNOON. Visit to the Steel Works of Messrs. Stewarts and Lloyds Ltd., Corby, Northamptonshire. Tuesday, August 23. Discussion on Repercussions of synthetic organic chemistry on biology and medicine (9.45). Prof. Sir F. GowLanp Hopkins, O.M., F.R.S.—Introduction. Prof. E. C. Dopps, M.V.0.—Synthetic estrogenic compounds (10.0).. The demonstration of the cestrogenic activity of simple molecules, bearing little or no relationship to the structure of the natural cestrogenic hormones, indicates that a complete change of view must be made on the question of the specificity of biological action. 'The work described shows that cestrogenic activity can be obtained by a whole series of different molecules without any apparent common physical or chemical property. The high degree of activity of 4 : 4’-dihydroxy-« : B-diethyl stilbene adds considerably more interest to this subject since this substance is several times more potent than the naturally occurring hormone. It would appear, therefore, that biological activity may be imitated by a whole series of substances, possibly quite foreign to the body. The bearing of this on the whole question of hormones and vitamins is of the greatest importance. Prof. L. Ruzicka.—Relationship between chemical constitution and physiological activity of androstane derivatives (10.20). The following androgens have been demonstrated in the human or animal organism: (1) Androsterone and trans-Dehydro-androsterone in human male urine; (2) Testosterone in bull’s testicles ; (3) Adrenosterone in the suprarenal glands of bullocks and cows; (4) Androstadienone in the urine of a man suffering from a tumor of the suprarenal gland. Of con- siderable importance is the quantitative difference in the physiological properties of androsterone and testosterone. Doses of androsterone and testosterone which exert an equal action on the growth of the capon comb show a quantitatively different influence on the growth of the seminal vesicles and prostate in rats, the testosterone being about five times more active in this last test. The difference in activity was the main reason for the preparation of numerous androgenic substances whereby it was hoped to ascertain the characteristic chemical constitution that was associated with typical testosterone activity. Only derivatives of androstane have been found to possess androgene activity ; it has not been possible to prepare androgenic compounds that differ in their constitution from androstane derivatives in the same degree as Dodds has succeeded in obtaining artificial cestrogens having a structure completely different from cestrane derivatives. More than fifty androstane derivatives have been prepared and their growth-promoting action on the capon comb and on the auxiliary sex glands of the castrated rat have been investigated. The majority of these andro- stane derivatives can be classed together in one group, the members of which differ from one another only in the details in positions 3, 5 or 17 of the androstane nucleus. The physiological activity in both tests depends upon the nature of the substituents in these three positions and on their 406 SECTIONAL TRANSACTIONS .—B. steric configuration. One of the possible two steric configurations is in each case more active physiologically and the physiological difference between compounds possessing these two configurations is greatest in the case of compounds differing in the 5-position, whereas position 17 has less influence and position 3 the least influence. With reference to position 5, that configuration is favoured physiologically which consists in a trans configuration of the rings A and B. The corresponding cis isomers are physiologically quite inactive. On carbon atom 17 the trans position of the hydroxyl with respect to the neighbouring methyl group leads to increased activity compared with the corresponding cis compounds, and on carbon atom 3 the isomers showing cis configuration of the hydroxyl with respect to the hydrogen in 5 are physiologically more active. epee OY See, The introduction of a double bond in position 5 leads only to a slight alteration in physiological activity. Moreover the double bond does not appear to be intimately concerned with testosterone-like activity when compared with the corresponding saturated derivatives. Of importance, however, is the presence of a keto group in position 3 which, in respect to the action on the seminal vesicles and prostate, is greatly superior to the corresponding hydroxyl derivative. A reversed relationship appears to exist for carbon atom 17 where a hydroxy group is found to be more active than a keto group. An increased activity of testosterone when it is injected in oil solution can be obtained by esterification, especially the propionate shows remarkably enhanced activity. It is established that a whole series of androstane derivatives show a weak cestrogenic activity.‘ It is not possible to define the details of the chemical structure characteristic for this activity in such an exact way as it is possible to determine the structural details associated with andro- genic activity. It seems, however, that the presence of a double bond in position 5 is of essential importance for the cestrogenic activity of androgens. For progesterone-like activity in androstane derivatives the double bond also appears to be necessary. Dr. A. S. Parxes.—Multiple biological activities of hormones and allied substances (10.40). The gonadal hormones and allied substances fall into three classes: the cestrone group, the progesterone group, and the androsterone-testosterone group. The substances of the first group, of which the better known are cestrone, cestradiol and cestriol, have primarily the power to evoke in the female reproductive tract the changes characteristic of the time of ovulation. In the male, these substances have an effect on the accessory reproductive organs, causing metaplasia of the epithelium or hypertrophy of the fibrous tissue, or both, according to the species of animal and the duration of treatment. No activity which can be called specifically androgenic is shown by these compounds. In both sexes the estrogens depress pituitary. activity, as may be seen by the effects on growth and on the gonads. Progesterone has primarily the power to cause progestational changes in the female reproductive tract. It has little direct effect on the reproductive SECTIONAL TRANSACTIONS .—B. 407 organs of the male or on the atrophic or undeveloped organs of the female— it has no androgenic or estrogenic power. The androsterone-testosterone group comprise three compounds which have been isolated from natural sources and a large number which have been prepared artificially. Most of these are able to stimulate the atrophic accessory organs and secondary sexual characters of castrated animals, i.e. they are androgenic. Many of them are gynzcogenic in that they will stimulate development of the reproductive tract in immature or ovariecto- mised females, while at least one, trans-androstenediol, is cestrogenic in the sense that it will cause cornification of the vagina in mice. ‘Testosterone and several other androgens when methylated in position 17, have the progesterone-like power to cause progestational changes in the uterus. Several of the androgens are able to depress the activity of the pituitary and cause atrophy of the gonads with consequent inhibition of the sexual cycle of the female. A similar indirect effect is also responsible for the depression of adrenal development seen in the male mouse, or in the female or castrated male receiving androgen. Both progesterone and the androgens are able to protect the organism from certain effects of the estrogens, an action which may be partly respon- sible for the effect of androgens on the intact female. Prof. J. W. Coox, F.R.S.—Polycyclic hydrocarbons with cancer- producing action (11.15). There is now a considerable group of polycyclic aromatic hydrocarbons which have the power of causing cancer. The disease so produced is indistinguishable in its characteristics from that which occursinman. The chief classes of cancer-producing hydrocarbons are (a) those derived from 1:2-benzanthracene (I) and (6) 3:4-benzphenanthrene (II) and its derivatives. (I) (IT) The former class has been extensively investigated and it is now possible to state some of the factors of molecular structure which are associated with cancer-producing activity. The twelve monomethyl derivatives of 1 : 2- benzanthracene have been synthesised and tested, and the only ones which have shown definite carcinogenic action are those with the substituent at positions 10, 5, 9, 6 (this represents a decreasing order of efficiency). Further, if simple alkyl substituents are present in two favourable positions of substitution they reinforce one another so that more potent compounds result. Such compounds are the 5 : 6-dimethyl and other 5 : 6-substituted benzanthracenes (Cook), 5 : 9-dimethyl-1 : 2-benzanthracene (Newman) and 5 : 10-dimethyl-1 : 2-benzanthracene (Fieser). The most powerful carcinogenic agent so far known is g : 10-dimethyl- 408 - SECTIONAL TRANSACTIONS.—B. 1: 2-benzanthracene (Bachmann), which gives multiple tumours much more rapidly than any other compound tested. Apart from g : 10-dimethyl-1 : 2-benzanthracene two of the most active cancer-producing compounds are 3: 4-benzpyrene, a constituent of coal tar which is undoubtedly responsible for skin cancer among tar workers, and methylcholanthrene, which may be prepared in the laboratory from cholesterol and the bile acids. Both these hydrocarbons are benzanthracene derivatives with substituents at positions 9 (in the case of 3 : 4-benzpyrene) and 5, 6 and 10 (in the case of methylcholanthrene). 3 :4-Benzphenanthrene has weak cancer-producing activity; its 2- methyl derivative is fairly potent, as is also 1 : 2 : 3 : 4-dibenzphenanthrene. The influence of substituents in other positions is being investigated (Hewett). Carcinogenic chemical compounds other than polycyclic hydrocarbons are also known. Dr. T. ReicHsTe1IN.—Partial synthesis of compounds related to the adrenal cortical hormones (11.35). The suprarenal glands are essential to life and the total removal of these organs leads to death, Each gland consists of two separate parts, the medulla and the cortex, the latter part of the organ being associated with the life-maintaining function. During the years 1929-1930 it was shown that extracts of adrenal tissue could be prepared which on injection into adrenal- ectomised animals maintained life. It seemed therefore that the most important function of the adrenal cortex was the production of one or more hormones. Such extracts are now prepared in large quantities for clinical use, In several laboratories attempts have been made to isolate the ‘ cortical hormone’ in pure form, and as a result of this work more than fifteen different chemically pure substances have been separated all of which appear to be sterol derivatives. Of these compounds only the four following sub- stances possess biological activity in adrenalectomised animals. OH O ——CO-CH,OH N | CO-CH,OH AS AS I Corticosterone II Dehydro-corticosterone OH OH a OH | | CO-CH,0OH ey | CO-CH,OH S 07\Z 07\4 III _17-Hydroxy-corticosterone IV 17-Hydroxy-dehydro- corticosterone Compounds I and II are more active than III and IV. These investiga- tions are made difficult owing to the approximate nature of the biological tests and the very large quantities of material they require. Furthermore SECTIONAL TRANSACTIONS.—B. 409 there is as yet no International Standard Unit of biological activity. It is generally agreed that certain amorphous adrenal cortex concentrates show greater biological activity than the pure corticosterone. It is possible therefore that there is in the whole extract an unidentified substance of greater activity. It is certain, however, that not a single life-maintaining hormone is produced by the adrenal cortex but a group of related substances some of which possess biological activity. Since it is not yet possible to make a complete synthesis of the sterol nucleus, only partial syntheses of compounds related to the adrenal cortical hormones have been achieved. The following scheme shows (steps V to XI) in outline a synthesis of deoxy-corticosterone (XI) from 3-hydroxy- aetio-cholenic acid (V) which can be obtained by degradation of chol- esterol or stigmasterol. “coo ila tN NN eC tCl | VO Ni: | OW eran. 0 WV. HO A ACOA WANK V V I /\|—_-co-cHN, |___co.CcHN; AA) rn YS sae ee v4 A ag VII VIII | CO-CH,OAc CH,COOH | Oar rae —>= CrO HO’ NZ te ic ( \—/-co-cH,0Ac a eer | CO-CH.OH ig — | i O7\4 xX XI Deoxy-corticosterone Deoxy-corticosterone (XI) differs from natural corticosterone (I) in not possessing a hydroxy-group in the 11-position. Biological tests have mostly been carried out with the acetate (X) of deoxy-corticosterone and the results indicate that the activity of this compound is greater than that of natural corticosterone. The acetate eliminates the pathological symptoms resulting from adrenalectomy in the same manner as the natural hormone. It seems probable that deoxy-corticosterone is the simplest compound showing full ‘ cortin-activity.’ Hydrogenation of the double bond prac- tically eliminates the biological activity. Elimination of the hydroxy-group 410 SECTIONAL TRANSACTIONS.—B, C. in the 21-position leads to a compound (XII) which occurs naturally, is known as progesterone, and is the active principle of the corpus luteum. OH CO-CH, ee oy ONT %\4A\/ (XII) Progesterone (XITT) This compound, however, shows no cortin-activity, which proves that the hydroxy-group in the side chain is essential. Compound (XIII) has also been synthesised, and this compound and also compound (IX) show no noticeable activity. More exact knowledge as to the relation between chemical constitution and biological activity must await the syntheses of further closely related compounds and of more detailed biological studies. yr Prof. A. R. Topp.—Vitamin B, and its synthetic analogues (11.55). The existence of an antineuritic factor (vitamin B,, aneurin) has been known for almost forty years, but its isolation in a pure condition from rice _ polishings was only achieved in 1926. The vitamin, usually isolated as its crystalline chloride hydrochloride C,,H,,ON,SCI, has been the subject of much chemical investigation leading to the elucidation of its structure and its complete synthesis, the latter being realised independently by German, American, and British workers. As a result of these syntheses the vitamin is now prepared commercially and has become available for clinical and nutritional purposes. With a view to determining the struc- tural features necessary for vitamin activity a number of synthetic analogues have been prepared. The results of this work indicate a remarkable struc- tural specificity, for, apart from alteration in the nature and position of the alkyl substituent on the pyrimidine nucleus, any change in the vitamin molecule destroys the physiological action almost completely. Although it is not yet possible to state with certainty the exact function of vitamin B, in plants and animals, it is clear that it plays an important réle as part of an enzyme system in carbohydrate metabolism. GENERAL DISCUSSION (12.15). AFTERNOON. Visit to the University Departments of Biochemistry and Parasitology. SECTION C.—GEOLOGY. Thursday, August 18. Prof. O. T. Jones, F.R.S.—The geology of the Cambridge district (10.0). Joint Discussion with Section K (Botany) on The post-glacial history of the Fenlands (11.15). Dr. H. Gopwin.—Introduction. The post-glacial deposits of the Fenland consist chiefly of peat beds on the landward side and brackish water or marine silts and clays on the SECTIONAL TRANSACTIONS.—C. 411 seaward side. These interdigitate as a result of former conditions of marine transgression and regression. ‘The work of the Fenland Research Com- mittee since its foundation in 1932 under the Presidency of Prof. Sir A. C. Seward, F.R.S., has been the correlation of the history of formation of these deposits with the evidence of geologists, archeologists, botanists and other specialists with as many as possible other events of local post-glacial history. For the outlines of the conclusions of this Committee see articles in the Scientific Survey, by Godwin, Clark, Phillips and others. Dr. W. A. MacrapyeN.—Foraminifera from the post-glacial Fenland deposits. The Foraminifera include an indigenous fauna, and derived specimens from the Cretaceous and Jurassic. Derived Jurassic specimens are only occasional, and seem to originate close to where they are now found. ‘The Chalk forms are a constant feature of the silts, and are considered to have been brought up the water channels from the sea coast, from outcrops of Chalk or Chalky Boulder Clay. Inthe buttery clay they are correlated with the subsidiary silt content. The indigenous Foraminifera include no extinct forms, and indicate no difference in climate from that of the present day. "They may be used as a scale of the salinity, which varied from estuarine to practically fresh water. The silts were characteristic of estuarine conditions, while the clays. were apparently deposited in lagoons, into which estuarine water occasionally overflowed. Different species of a genus of Foraminifera exhibit varying tolerance of admixed fresh water, and this is here most clearly exemplified in the genera Quinqueloculina, Trochammina,, Bolivina, Laggna, Discorbis, Nonion and Elphidium. Nonion depressulus and Rotalia beccarii can flourish in water that is practically fresh, and the species of Trochammina appear definitely to prefer a somewhat brackish habitat. \ Mr. H. L. P. Jotty.—Levels and bench marks. The bench marks of the Ordnance Survey are habitually placed upon structures which bid fair to be the most stable. Hence the great sub- sidences in the fen levels due to drainage are not recorded by any of the re-levellings which have been carried out. For much of the area there exist records of three levellings dated approximately 60, 30 and Io years ago. In general, these show no appreciable changes wherever the bench marks are on buildings situated more than 20 ft. above mean sea level ; situated, that is, on outcrops of Cretaceous or older rock and not on the alluvium. Some bench marks have of necessity been placed in the drained districts and these, being generally on houses or other brick structures placed on or near an artificial bank, have shown subsidences of from nothing to 1 ft. or even nearly 2 ft. Such measurements serve, however, only to give precision to what is otherwise very patent to the eye, for the houses bear much evidence of subsidence in the shape of cracks, tilting or even collapse. This is especially the case where, as often, the house is built as close to the bank as possible, so that one end of it rests on the bank and the other on or near the fen. The Middle Fen Bank at Prickwillow has a colony of houses, all of which show distortion of some kind. The maximum subsidence shown there by Ordnance Survey bench marks is 0°74 ft. between the years 1870 and 1go1 and a further r:o ft. between 1go1 and 1925. Evidence of soil subsidence beyond that recorded by the 412 SECTIONAL TRANSACTIONS.—C. bench marks may occasionally be seen where an unused front door to a cottage is now seen to be 24 ft. above ground level and yet unprovided with any step. A line of special levels has been completed quite recently in the vicinity of the famous iron column at Holme Fen with a view to finding out what subsidence has taken place since the year 1885. At that date there were already spot (i.e. ground) heights on a drift in the vicinity a foot or two below mean sea level, a not uncommon thing in the Fens. At the foot of the column the ground level is now found to be 7 ft. below mean sea level. Dr. J. G. D. CLarx.— Archeological correlation. Archeological-geological correlations have been effected in the Cambridge- shire Fens by sectioning post-glacial deposits formed in close proximity to and contemporaneously with sites inhabited by prehistoric man. By recording accurately in the section the ‘ scatters’ (bones, flints and sherds) from successive settlements their stratigraphical relationships have been established and their contexts in the natural sequence of events accurately fixed. Correlations effected by this method are considered more reliable than those obtained by means of chance finds of stray objects or hoards, many of which have been inserted from higher levels. By utilising a “scatter ’ of objects of varying weights the factor of sinkage is also brought under control. Sections cut on either side of the channel of the extinct course of the Little Ouse on Peacock’s ! and Plantation Farms, Shippea Hill, near Ely, gave three archzological levels in the post-glacial sequence, viz : Early Bronze Age in the base of the Upper Peat. — 6 ft. O.D. N.B.—Fen clay sterile. Neolithic ‘ A’ near the top of the Lower Peat. — 15 ft. O.D. Late Mesolithic in a black band at a ‘lower depth in the Lower Peat. — 17 ft. O.D. The subsidence revealed by the O.D. levels reached its climax during the Early Iron Age, when the Fens were virtually evacuated. This is well illustrated by comparing maps ? showing the distribution of finds dating from the Bronze and Early Iron Ages respectively : areas densely settled during the former period appear to have been abandoned completely during the latter. Mr. C. W. PHILLies.—Conditions in Roman times. At the opening of the Roman period the Fens were deserted, but by A.D. 100 an extensive agricultural occupation of native type had set in, chiefly on the silt lands. It is probable that the area was an Imperial domain. Work at Welney has shown that by the end of the second century sea-floods began, but the wealth and activity of the region continued with little abatement, so far as we know, till late in the fourth century. In Anglo-Saxon times the region was again a wilderness. The particular interest of the occupation is its size, intensive character, and the various types of native agriculture displayed. The suggestion is that the population was drawn from more than one part of Britain and that 1 It is hoped to re-open this key section on the occasion of the Cambridge Meeting of the Association. 2 See the Scientific Survey prepared for the present meeting of the Association. SECTIONAL TRANSACTIONS.—C. 413 it was entirely peasant in character. No administrative centre is known, but this may have been at Durobrive (Castor-Water Newton) on the western fringe of the region. There is no positive evidence of Roman drainage works on any scale, and the occupation and abandonment of the region appears to have depended in the main on the operation of natural causes. Prof. H. H. SWINNERTON.—The marshland of east Lincolnshire. The Lincolnshire marshland is the northerly continuation of the Fenland. As its coastal margin is undergoing marine erosion many natural exposures of the underlying deposits are available. These show that the general history of the area is one of recurrent alteration in the relative level of land and sea, accompanied by the laying down of alternating deposits of estuarine clays and fen peats. The youngest deposits consist of silty clay containing cockles, oysters and Scrobicularia, which show that it was laid down in the low tide zone. This clay rests upon a surface well defined by a thin peat, the presence of a Roman site and the debris of many early Iron Age salt- workings. ‘These facts suggest a stationary condition for the area from the close of the Bronze Age to the last century of the Roman occupation, fol- lowed by a rapid subsidence of nearly 20 feet. Underlying this surface the following deposits occur from above downwards: thin freshwater clay ; 8 feet of marine silts, crowded with the remains of salt marsh plants; and 2 feet of peats, enclosing the ruins of a forest. The last named have yielded one implement of neolithic type, and the composition of the peat points to the climatic conditions of the latter part of the Atlantic Period. The clays with salt marsh plants thus represent a subsidence, during the Bronze Age, which took place so slowly that the area was always situated within the limits of the high tide zone. AFTERNOON. Excursion to Barnwell, Cherryhinton, and Barrington. ‘ Friday, August 19. Discussion on The distribution and migration of certain animal groups in the British Lower Paleozoic Fauna (10.0). Dr. C. J. STUBBLEFIELD.—1. The Trilobites. * Larval ’ trilobites were presumably planktonic, adults neritic or nektonic. Some genera are more usually found in mudstones, others in calcareous or sandy deposits, many are independent of facies; trilobites are notably absent from truly planktonic deposits—radiolarian cherts, graptolite shales (s.s.). The geographical affinities, changes and distribution of successive faunas are discussed. The contrast between the faunas of the Scots-Irish area and the Anglo-Welsh area persists from Lower Cambrian to Balclatchie times with possible intermigration in the south about the time of Nema- graptus gracilis. ‘These Scots-Irish faunas have affinities with the Appalachian and Baltic regions. In Arenig times, in the Anglo-Welsh area the earlier faunal affinity with Scandinavia is lost ; new genera appear in South Wales ; the arenaceous Synhomalonotid fauna spreads to North Wales and Shrop- shire but the Cyclopygid-Trinucleid fauna also reaches the Lake District. Llanvirn faunas of South Wales and Shropshire have Bohemian relation- ships ; Llandeilo, and early Caradoc of East Shropshire also show southern 414 SECTIONAL TRANSACTIONS.—C. elements. The Caradoc Homalonotid-Acaste fauna (in part of southern origin) spreads from East Shropshire across North Wales and to north and east fringes of Lake District ; it later receives Chasmopids (of Baltic origin) probably from the west. A foreign fauna invades mudstones in Scotland and Central Wales about the time of the Caradoc/Ashgillian junction and the Welsh and Lake District limestones take on a Scots-Irish faunal aspect. Later Ashgillian faunas discussed. Llandovery faunas less differentiated geographically than Ordovician, some genera appear or re- appear earlier in north than in south, ancestral Wenlock elements evident. Wenlock faunas most luxuriantly developed in south-east. Ludlow trilobites (in Anglo-Welsh area only) waning in importance. Dr. G. L. ELLEs.—2. The Graptolites. Graptolites (Graptoloidea) essentially planktonic, distribution intimately connected with mode of life ; effected by currents, whether (a) attached to host, (6) as free swimming germs or (c) as free swimming maturer in- dividuals ; time taken in migration negligible compared with rate of deposit of rocks in which they occur. Factors affecting completeness of succession : (a) quietness of waters ; (b) facies ; (c) structural considerations. Complete succession at any one time may be: (1) Condensed (perhaps planktonic) ; (2) Spread out (drifted) ; (1) is richer fauna, (2) gives relative ages more accurately. Remarkable continuity in faunas where succession complete and fundamental world-wide assemblages at corresponding horizons, some difference in detail in different regions possibly due to migration. Analysis of successive Graptolite Faunas of the British Lower Palzozoic Geosyncline in relation to those of extra British areas. Possible interpreta- tion of certain features. Dr. A. LamMont.—3. The Brachiopods. Shallow water, sessile; brief drifting life; wide or deep seas, muddy belts, climate, land, as barriers. Coarse-ribbed Orthis carausii (Arenig) in sands. Large body-spaced _Porambonites intercedens (Llianvirn) in limestone indicating clear water. P. filosa (? horizon) in limestone indicating clear water. Small Leptelloidee in muds of Tramore limestone ; higher beds reaching a Mesograptus foliaceus- Nemagraptus gracilis horizon. Common source of Scots, Irish, Welsh faunas about this time. American comparisons. Dinorthis flabellulum, Nicolella actonie, Orthis calligramma, coarse-ribbed, large volume, in sandy limestone or sand ; poor horizon-markers. Com- pressed or diminutive individuals in shales. (?) H,S poisoning. Adaptation to poverty of oxygen in water above mud. ~Sowerbyella, narrow body uses minimum oxygen, extended margin collects from wide area. Individuality of Anglo-Welsh Caradocian fauna, Wattsella, Kjzrina, not accounted for by sea-floor. (?) Land barrier through Saltees. Scots-Irish conquest (Ashgillian) of Anglo-Welsh area; Schizophorella fallax in Dolhir beds Glyn Ceinog ; Fardenia cf. scotica in Cyrn-y-brain beds, Llangollen. Percé (Quebec) comparisons. Llandovery—cosmopolitan. Distribution of Pentamerus oblongus. Maroon shales, Walsall boring, current-bedded, large Brachyprion, Schucher- tella, Stricklandia lirata forma typica ; the last in length of apertural margin/ ~ body volume ratio exceeds S. lirata var. « from coastal sands. Considerable oxygen available due to (1) small organic content of muds, (2) little volcanic a 1 SECTIONAL TRANSACTIONS.—C. 415 material, (3) large surface area of sea in relation to depth, (4) disturbance by wind. Other problems. Dr. W. K. Spencer, F.R.S.—4. The Starfishes and Cystids. These are not homogeneous faunas developing in their own areas, but migratory faunas brought in at various times by various floodings. History then can only be followed in relationship to larger considerations. 1. Cambrian.—Only fragmentary ‘ Cystid’ remains are recorded from Britain. Stromatocystis is found in Newfoundland and Bohemia suggesting a trough connecting these areas. The Carpoids (a stock near akin to ancestral starfish) are confined to Bohemia and Languedoc. 2. Tremadoc—New cystids and first starfish in Languedoc fauna, Macrocystella (cystid) in Shropshire. 3. Arenig.—Ramsay Island fauna. 4. Llanvirn—A rich and varied development from fauna (2) in Bohemia (D,y) ; greater part of starfish fauna still archaic, also brittle stars with true starfish; carpoids and cystids. Only British echinoderm belonging to the Bohemian-Languedoc fauna is a species of Paleura found in the zone of Didymograptus bifidus (Upper Hope Shales of Shropshire). 5. Caradoc-Bala Fauna.—Middle Ordovician of Chinese Turkestan has the three species of Spy Wood Grit (early Caradoc) of West Shropshire fauna and Stenaster also found in Wales. ‘The Bala Cystids are also related to those found in Asia. The genus Siluraster found in the Bala beds in Wales and Shropshire has distinct relationships with the Bohemian D,y and D, faunas. The Bala fauna also has relationships with the Canadian and Kentucky Trenton faunas. 6. Starfish Bed, Girvan—Rich Echinoderm fauna; (a) Starfish are related to those of Richmondian of Ohio Basin (and some Trenton forms) together with a new fauna. This combination later dominates the Silurian and Devonian. The faunas are quite different from Welsh-Bohemian fauna (5), the only Welsh-Bohemian-Central Asiatic elements are those also found in the Trenton. (b) Cystid fauna has same two constituents, i.e. American and a new fauna which is really an old fauna (2) as developed in Languedoc. The number of peculiar genera common to both is very remarkable. An explanation might be an Eastern reservoir sending migrants by an Arctic route to Girvan. Starfish are not known from the con- temporary Welsh, Irish or Baltic beds. Cystids in these three areas are as a whole different from those of Girvan and have a common element, apparently Baltic in origin. 7. Wenlock of Pentland Hills shows fauna of affinities with Girvan (6) together with new species from the north-east. Wenlock of Central England brings in new forms related to contemporaneous American faunas, differing from Scottish fauna. 8. Ludlow of Leintwardine and Lake District has derivatives of Girvan (6), suggesting that that fauna had moved southward, plus some elements related to Languedoc (2). AFTERNOON. Excursion to Upware and Warboys. Saturday, August 20. Excursion to Thrapston and Stamford. 416 SECTIONAL TRANSACTIONS.—C. Sunday, August 21. Excursion to the Brecklands. Monday, August 22. PRESIDENTIAL AppRESS by Prof. H. H. SwINNERTON on Development and evolution (10.0). (See p. 57.) Discussion on The origin of carbonate rocks associated with alkali-rich intrusions (11.15). Dr. H. voN ECKERMANN. Daly mentions the Alné alkaline area as clear evidence of carbonate- syntexis. A new survey, however, has proved the existence of a confocal stereometrical distribution both of the carbonatites and the alkaline rocks in general. The emplacement of the rocks is similar to that of Julianehaab and Umptek, as emphasised by Backlund. The carbonatites of Alné, consequently, are not metamorphic limestone-xenoliths. Nor is such a syntexis supported by mineralogical and chemical evidence or by our present knowledge of the Fennoscandian rock-ground. Surrounding the Alné-neck, carbonatitic (calcitic or dolomitic) cone- sheets, converging towards the apex of a diatreme, are cut by vertical, radiating alnditic dykes corresponding to the damkjernites of Fen and representing iron-rich magma risen from below on the blowing out of the diatreme. A gravitational magmatic differentiation accompanied by rising CO,-concentration is suggested. The CO, seems to have greatly affected the normal equilibria of the rock components. The discovery of carbonate-bearing differentiates of alkaline character, associated with basic Jotnian magmas, suggests a differential relationship between the latter and the alkaline rocks of Fennoscandia. The incongruent melting of orthoclase, previously emphasised by Bowen, may be reconsidered from a new angle, involving the Jotnian tensional earthcrust-stresses and the presence of CO . The Fennoscandian alkaline intrusions—except the post-Caledonian Seiland dykes—are all of the same pre-Cambrian and late- or post-Jotnian age. Whether they are associated with carbonatites or not, they owe their birth to the same fundamental principles. The accumulated evidence of the last few years justifies the draft of a tentative common petrogenetic scheme, which may serve as a basis of further discussion. Lt.-Col. W. CAMPBELL Sm1TH.—Alkali-rocks associated with limestones of apparently intrusive nature in southern Nyasaland. In the neighbourhood of Lake Chilwa and elsewhere in southern Nyasa- land some alkali-rocks occur in and about a number of vents of supposedly volcanic origin filled with brecciated feldspar-rock intimately associated with crystalline limestones. The field-occurrence of these rocks has been fully described by Dr. F. Dixey of the Geological Survey of Nyasaland. The crystalline limestones of the Basement Complex in the district are of negligible bulk as compared with those of the volcanic vents and are different in composition. The feldspathic breccias of many of the vents consist of angular fragments of orthoclase-rock with unusually high potash content, SECTIONAL TRANSACTIONS.—C. 417 up to 13%. The gneisses and other rocks around the vents are intensely altered, the end-product being a feldspar-pyroxene rock in which the pyroxenes are egirine and egirine-augite. These rocks correspond to the fenites and tveitasites of the Fen district in Norway. The fenitisation seems here to be due to emanations accompanying the emplacement of the limestones and feldspathic breccias rather than to the small intrusions of alkali-rocks (foyaite, ijolite, and nephelinite) which cut the vents and are clearly later. It does not seem possible to explain the crystalline limestones in these vents as due to carbonate replacement. They seem to be of magmatic origin and to be comparable to the magmatic limestones or carbonatites of Alné in Sweden and the Fen district. Their origin and their mode of emplacement are problems which still await solution, and these problems may be related to the problem of the origin of the associated alkali-rocks. Mr. S. I. TomKererr.—The réle of carbon dioxide in igneous magma. All igneous rocks are known to contain CO, in varying quantities, but it is probable that the greater part of the CO, originally present in any magma escaped during the consolidation. Certain rocks and rock-series are especi- ally rich in COz, and given suitable conditions during the last magmatic stages, not only did the carbonates crystallise out, but they formed an independent carbonatite magma-fraction. Many occurrences of such igneous carbonatite rocks are known, the one best studied being the Fen district of Norway. The circular outcrop of alkaline and carbonatite rocks of Fen probably represents the stoped head of a pipe infilled with a basic alkaline differentiate of essexitic magma (Oslo district type). One may postulate that the upper zone in the pipe was originally composed of an alkali-pyroxenite magma rich in CO,. Crystallisation-differentiation, combined with diffusion of alkalies and volatiles, gave rise to three main rock-series : (1) Urtite—Jacupirangite series. (2) Iron-ore series (R6dberg—Hematite ore). (3) Ca-Carbonate series (Kasenite—S6vite). The magma of the principal series (Urtite—Jacupirangite) assimilating the country rock (Granite) gave rise to a hybrid alkali-syenite magma (Juvite-Tveitasite series). The bordering gneiss-granite transfused by alkali-alumina emanations derived from the main magma was transformed into a pulaskite rock (Fenite). The residual liquid of differentiating magma, rich in CO, and iron oxides, gave rise to the late consolidated fractions of iron ore and carbonatites. The evidence both of its field occurrence and of its petrographical characters of Damkjernite suggests that this rock had been derived from a lower zone of the pipe composed of alkali-peridotite rich in CO,. The shattering of the consolidated portion of this magma by the residual volatiles and its subsequent eruption through the rocks belonging to the earlier stage, gave rise to the Damkjernite—Rauhaugite series rich in Mg and K. The réle of CO, in magma is not limited to the formation of magmatic calcite and carbonatites. It is quite obvious that the presence of CO, affects the equilibrium between other components in the magma and in this way determines the formation of minerals. One may suppose that the spilite-keratophyre series, and probably the lamprophyre series as well, owe their peculiar character to the presence in them of a relatively large amount of CO,. The spilite-keratophyre series in its chemical composition P 418 SECTIONAL TRANSACTIONS.—C. does not differ much from a typical alkalic series, such as the rocks of Oslo district or the British Carboniferous-Permian igneous rocks, except for its considerable larger amount of CO,. Prof. C. E. TiLuey, F.R.S. AFTERNOON. Excursion to Wood Ditton and Underwood Hall. Tuesday, August 23. Dr. S. BucHan.—Pollution and exhaustion of London’s underground water supply (10.0). A general progressive lowering of the level of water in the underground reservoir of London has been taking place over a long period, but during the past few years the fall has become more marked and it is now evident that, unless the fall is checked, parts of the reservoir will be exhausted in 35 years or so. ‘The truly artesian conditions of a century ago are gone, and in one area the surface of the water stands 300 ft. lower than it did 60 years ago. Water is being extracted from the centre of the London Basin more rapidly than it is replenished. Locally, the sands above the Chalk have been drained and dry areas are spreading as the water-level falls, while, in the Chalk, areas are developing from which only a poor supply is likely to be obtained. The importance of the geological structures in controlling the distribution of water is becoming apparent now that it is possible to define the principal areas from which the supply is flowing to London. Owing to the geological structure the lowering of the water-level has caused brackish water to flow from the tidal reaches of the river Thames into the Chalk and to pollute the supply in an area of high-yielding wells. As the fall in level continues, pollution will become more intense and will affect a greater area of London as well as an increased depth of Chalk. The large number of abandoned wells create another potential danger to the water supply. Deterioration of their seal or lining tubes will allow the entry of contaminated water from the superficial deposits to the Chalk. Mr. S. I. TOMKEIEFF.—Zonal olivines and their petrogenetic significance (10.35). The measurement of the optic axial angle. of olivines from various igneous rocks shows that nearly all olivines are zonal. The only exceptions are olivines from ultra-basic rocks and olivines from alkaline acid and inter- mediate rocks. As a rule the zoning is continuous and it shows a pro- gressive enrichment of the mineral in iron towards the periphery. The difference in composition between the centre and the outer rim can reach 40 % fayalite, but such cases are rare. In the British Carboniferous dolerites, for example, olivine on the average shows 31 % fayalite in the centre and 39 % in the outer zone, while the olivine from the British Tertiary dolerites shows 18 % fayalite in the centre and 40 % in the outer zone. A progressive variation in the average composition of olivine occurring in the different phases of a single intrusive mass is demonstrated by the SECTIONAL TRANSACTIONS.—C. 419 study of the dolerite sill of Fair Head, Co. Antrim. In this sill olivine has the following average composition: (1) from the glomeroporphyritic aggregates (allivalite) representing an early phase of crystallisation— 24 % fayalite ; ; (2) from the dolerite—43 % fayalite ; (3) from the dolerite- pegmatite schlieren, a late phase—71 % fayalite. There seems also to be some relation between the variation in the composition of olivine and that in the composition of the rock in which it occurs, an increase in the iron content of the olivine being usually accom- panied by a similar increase in the alkalies and silica content of the rock. The parallelism between the zonality of olivine crystals, the variability of the composition of olivine in the successive magmatic phases and the relation between the composition of the olivine and the magma, has a definite bearing on the question of petrogenesis. The recorded observa- tions—which are in perfect agreement with the recently published study on the forsterite-fayalite binary system by Bowen and Schairer—show the possible control exercised by olivine on magma and the relation between the composition of the olivine and that of the magma. Dr. F. Watxer.—The differentiation of the Palisade diabase sill, New Jersey (11.10). A detailed quantitative examination of the best exposed sections through the famous Palisade Diabase Sill leads to the following conclusions : (i) It is doubtful whether the ‘ olivine layer’ in the lower part accum- lated by gravitational settling of olivine. (ii) There is a definite gradational concentration of pyroxene above the “ olivine layer,’ indicating sinking of pyroxene. (iii) Assimilation of arkose on a large scale is improbable. (iv) The proportion of free silica in the sill as a whole is very small, but there is a marked concentration just below the upper chilled phase. (v) The magmatic history of the sill ended with pronounced hydro- thermal activity. Dr. A. Wave and Dr. R. T. Priper.—The geology and petrology of the leucite rocks of the Kimberley district, Western Australia (11.45). Nineteen occurrences of post-Permian volcanic rocks have been found in the West Kimberley area. Plugs, partly eroded craters and fissure intrusions have been recognised. ‘The structure and distribution of these occurrences indicate that the intrusions have ascended along fault planes which are connected with the structure of the underlying pre-Cambrian rocks. The rocks are made up of varying proportions of leucite, phlagopies diopside, simpsonite (a new K-Mg. amphibole related to katophorite), wadeite (a new K-Zr silicate), rutile, chlorite and indeterminable ground- mass. Four new rock types (fitzroyite, cedricite, mamilite and wolgidite) are described. Although leucite is developed to the complete exclusion of sanidine, the rocks contain more than sufficient silica to have formed orthoclase instead of leucite. 2The magma, from which these rocks crystallised, was of peculiar character—its main features being high potash dominant over alumina, high magnesia and titania and very low soda content. The minor constituents are comparatively abundant. This magma was probably derived from a potassic mica-peridotite magma 420 SECTIONAL TRANSACTIONS.—C. by the early crystallisation and removal of olivine. The siliceous and potassic residuum crystallised at temperatures above the leucite-orthoclase reaction temperature and was extruded as a crystal mush which has effected little change in the intruded sediments. Chilling of the acid residuum has inhibited ‘the leucite to orthoclase reaction. The only comparable rocks are the wyomingites and orendites of the Leucite Hills, Wyoming. Dr. F. Cotes Puitiies.—The fabric of some ‘Tarskavaig Moines’ (12.20). The ‘ Tarskavaig Moines,’ a series of phyllites and schistose grits, occur in the Sleat district, Skye, to the north-west of the Moine Thrust, above a subsidiary dislocation, the Tarskavaig Thrust. On the Geological Map of Scotland issued in 1892 they were coloured as Torridonian. They were later regarded by C. T. Clough (mainly because of supposed similarities in stratigraphical sequence) as less-altered representatives of the same great formation as the Moine rocks on the other side of the Moine Thrust. This view has recently been questioned by H. H. Read, who considers the Tarskavaig rocks to be Torridonian affected by the post-Cambrian disloca- tions, and regards apparent transitions from unaltered Torridonian to true Moine rocks as a result of metamorphic convergence. The fabric has therefore been examined in an attempt to determine the direction or directions of movements to which these rocks have been subjected, and comparisons are instituted between the grain-fabric of the Tarskavaig rocks and of Torridonian and Moine rocks from adjacent districts. These are believed to show that true Moine rocks have been affected by regional movements along a south-west and north-east direction, no trace of which can be found in the grain-fabric of the Tarskavaig rocks. AFTERNOON. Excursion to Barley and Barkway. Dr. S. R. Nockotps and Dr. J. E. Ricuey, F.R.S.—Replacement veins in the Mourne Mountains granites (2.15). All the Tertiary granite masses of the Mourne Mountains are traversed. here and there by narrow replacement veins which belong, in general, to the greisen class ; the prevalent variety being dark-green in colour. ‘They are either steeply inclined or vertical, are found in greatest number at places: close to a granite margin, and can be shown in several instances to be parallel to the plane of contact. Their position in the igneous history of the granites is indicated by the fact that they cut the later aplite veins but are themselves traversed by well-developed joint planes. The dominant type of vein is composed of aggregates of topaz and a peculiar blue-green mica together with quartz. Other constituents include some independent topaz, fluorite, stilbite, chlorite and sometimes a little biotite. Subordinate types are represented by white mica-chlorite-quartz veins with minor fluorite and stilbite, grey quartz-magnetite veins and black veins rich in manganese ores. There occur, in addition, certain fissure veins which follow, and are later than, the joints. "The dominant variety is composed of iron rich chlorite, associated with colourless granular fluorite, albite and very subordinate orthite. SECTIONAL TRANSACTIONS.—C. 421 Mr. S. O. AGRELL.—Adinoles of Dinas Head, Cornwall (2.45). Adinoles associated with spilosites and spotted slates occur at the contact of an albite-dolerite intrusion with black limestone-bearing slates of Upper Devonian age. They consist of albite and quartz with accessory leucoxene, and with or without chlorite, dravite, ankerite and calcite. Four main types are recognised : 1. Normal adinoles—structureless albite-quartz rocks showing sedi- mentary banding and grading into rocks composed essentially of dravite. i 2. Adinoles with pseudomorphs probably after andalusite. 3. Adinoles with globular masses of ankerite showing concentric structures. 4. Polygonal and spherulitic adinoles. Chemically, the adinoles resemble quartz-keratophyres and their tufts, but the evidence at Dinas Head shows that they are due to the effect of the intrusion on the sedimentary rocks. ‘The first change was purely thermal and was followed by albitisation and then by carbonatisation, the meta- somatising fluids coming from the dolerite. The adinolisation is a volume for volume replacement and calculation on analyses shows that soda, silica and sometimes boric oxide have been fixed in the slates. As a result of faulting and of the ramifications of the intrusion the adinoles appear up to eighty feet thick, but actually, they form a veneer over the headland and never extend more than thirty feet from an igneous contact. Mr. G. ANDREW.—Some granitic intrusions in the Central Eastern Desert of Egypt (3.15). The intrusive granites may be divided into groups on the basis of the nature of the contact. 1. Abu Ziran type.—Injection-gneiss, strongly banded, generally foliated, protoclastic or cataclastic structures common. Xenoliths within mass granoblastic, near margin foliated. Injection zone in pelitic rocks accom- panied by kyanite, staurolite and almandine as contact minerals. Re- crystallisation falls off away from granite-margin, but is still of regional type. Intrusion of syntectonic type. 2. Belih type—Porphyritic, often foliated locally. Contact irregular, either steeply plunging discordant, or approximately horizontal discordant in bathyliths. Country-rock thoroughly recrystallised, normal hornfels- structures and contact-minerals, veined. Assimilation considerable, with . xenoliths common and remote from margin, traceable in granite in the form of ‘ basic clots.’ Margin usually granite-porphyry. 3. Um Disi type—Even grained, often fine-grained, non-porphyritic, unfoliated. Contact sharp, steeply plunging discordant. Country-rock affected to a notably less degree in comparison with Belih type. Normal hornfels-structure and minerals. Veining rare, assimilation negligible, and xenoliths are rare, and sharply bounded. Margin often coarse, pegmatitic. 4. El Atrash type—Almost entirely a quartz-feldspar rock, in small masses, frequently with a dyke form (W.N.W. to N.W. strike). Coarse varieties granitic, finer grained type is spherulitic or micrographic. Contact metamorphism very slight, confined to a few metres width, even in masses of 4.sq. km. area. Rarely xenolithic. Type 1 is only known in the regionally metamorphosed paraschists south of G. Me‘atiq. The remainder intrude the Dokhan series and’ other 422 SECTIONAL TRANSACTIONS.—C. unmetamorphosed sediments, and are arranged in order of age. The riebeckite granites are not included in this table and form a still younger group than 4. Mr. G. ANDREW.—On the upper pre-Cambrian of the Eastern Desert of Egypt (3.30). Between latitude 26° N. and 28° N. the stratified rocks forming the hill region west of the Red Sea are largely unmetamorphosed. Three series may be distinguished : 3. The Hammamat series, consisting of purple (lie-de-vin) and green mudstones, greywackes and conglomerates. 2. The Dokhan series, consisting of similar sediments, with intercalated pyroclastic rocks and lavas. 1. The Atalla-Rubshi series: grey mudstones, often phyllitic, some greywackes, and rhyolites with tuffs. The stratigraphical relations of the three series to one another are not known, since all contacts seen are faults. Dips are high, strikes variable : north-north-west in the Atalla-Rubshi series, north-west to north-north- west in the Hammamat, and north-east to north in the Dokhan series. The lithological types of the Hammamat series may be recognised over a wide area in an unmetamorphosed state, e.g. Bir Kareim, Dungash, Wadi Khashab, Wadi Hamata, and north of Um Garaiart. In the same way the Dokhan type occurs in Wadi Hamish (Wadi Shait), Wadi Sheikh Shadli— G. Abu Hammamid, Wadi Huluz, and in the Wadi Allagi region. The Atalla-Rubshi series is less distinctive, and not recognisable elsewhere at present. These series may be classed as Algonkian, and include the Eparchzan and part of the Metarchzean of Hume (1934). ‘The rocks are typically non-schistose, except in narrow zones of movement, and in the contact-zone of some granites. Dr. A. G. MacGrecor.—Characteristics of West Indian tridymite and cristobalite (3.45). Exhibit of microphotographs (lantern slides) illustrating the mode of occurrence and diagnostic features of the tridymite and cristobalite of the porphyritic bandaites (labradorite-phyric dacites) of Montserrat, B.W.lI. Tridymite is an abundant primary groundmass-constituent ; cristobalite is also very prevalent and can, in some cases, be shown to replace original tridymite. The cristobalite exhibits certain features recalling those often described as characteristic of tridymite. Wednesday, August 24. Dr. E. B. BatLey, F.R.S.—Caledonian tectonics and metamorphism in Skye (10.0). The geology of the Kishorn Nappe is reviewed from Loch Kishorn on the mainland through the greater part of Sleat in Skye. The fundamental facts are taken from Peach, Horne and Clough. The latter’s magnificent work in Skye has been amended in certain details, and this has tended to clarify the general situation. The Kishorn Nappe consists mainly of Torridonian, with Lewisian north of Loch Alsh (Sheets 81, 71), and Cambro-Ordovician west of Ord on Loth Eishort (Sheet 71). The nappe is underlain through much of its SECTIONAL TRANSACTIONS.—C. 423 extent by a complex of moved Cambro-Ordovician, which is exposed at the head of Loch Kishorn and again in the Suardal Anticlines of Skye and in a window east of Ord. The top of the Kishorn Nappe is furnished by the base of the Moine Nappe, except near the Point of Sleat, where the Tarskavaig Nappes intervene (Sheets 71, 61). A great inversion, called the Loch Alsh Inversion, is the main structural feature within the Kishorn Nappe. It is part of a recumbent fold that runs obliquely to the course of the Kishorn and Moine thrusts, that truncate it from below and above. Thus at Loch Kishorn, only the upper inverted limb of the recumbent fold is preserved ; at Loch Alsh, both limbs occur ; while in most of Sleat, only the lower normal limb is found. The upper limb shows a cleavage, or foliation, that scarcely penetrates at all into the lower limb, and with this foliation there is in places mineral development leading to a production of minute micas, including brown biotite. The generally normal lower limb of the Loch Alsh Fold develops an additional local recumbent fold exposed west of Ord, near the window already mentioned. The inversion connected with this Ord Fold is un- accompanied by cleavage or metamorphism. Moreover, it does not extend up to the base of the overlying Tarskavaig Nappes. The Tarskavaig Nappes emerge from under the Moine Thrust, and agree in structural position with the Loch Alsh Inversion, except that they have travelled forward by thrusting rather than inversion (cf., however, the Balmacara Thrust of the Loch Alsh district). ‘Their metamorphic grade is closely comparable with that of parts of the Loch Alsh Inversion. It is true that in addition to a widespread development of minute biotite, in part brown, Clough found 1 mm. garnets at one locality; but these latter, after separation by A. F. Hallimond, have been analysed by C. O. Harvey; and proved to contain sufficient manganese to be natural associates of biotite in its early stages of formation. The writer feels that the correlation of the Tarskavaig ‘ Moines ’ with the Torridonian, a view favoured by Peach, Read and others, is distinctly strengthened. He welcomes the altogether new evidence furnished by F. C. Phillips during the current session of the B.A. It is hoped to expand this account in a forthcoming Geological Survey Bulletin. Dr. E. B. BatLey, F.R.S.—Tectonics, erosion and deposition (10.30). (1) Antecedent Drainage.—In maturity antecedent drainage often looks wellnigh unbelievable, for it seems like special pleading to speak of a barrier of hard rock raised so slowly as not to divert a river of soft water. One is apt to forget that during early stages of mountain elevation a river may have to cope with nothing more resistant than sand and clay. By the time it reaches hard core rocks it may already be entrenched in a valley thousands of feet deep, and therefore able to defy intermittent attacks by earth movement, however strong the material that is employed. This sort of relation is illustrated in some of the anticlines associated with the Caucasus. (2) Cross-mountain Contrasts Sometimes the two sides of a mountain chain, great as the Urals or small as the Malverns, show a wonderful con- trast. On the one side the junction between the mountain-rocks and those of the adjacent plain may be tectonic, and on the other side, erosional. As a broad generalisation this is illustrated at the junction of the Urals, west- wards with the Palzozoics of the Russian Platform and eastwards with the Tertiaries and Quaternaries of Asia; or at the junction of the Malverns, westwards with the Old Red of Hereford and eastwards with the New Red 424 SECTIONAL TRANSACTIONS.—C. of Worcestershire. In either case we are dealing with a mountain chain, or ridge, that to begin with separated a high plateau from a low plain. Until deposition overtook erosion the main tendency was for the low plain to extend ever farther into the mountain territory. What remained of the hard core rocks of the mountain functioned meanwhile as a bulwark, pro- tecting the high plateau from encroachment of the plain. ‘Then came deposition, building up the low plain in relation to the high plateau. Thus the original contrast of level on the two sides of the mountain was eventually replaced by a contrast of material. Mr. J. F. Kirxatpy.—The constituents of the pebble beds of the Lower Cretaceous rocks of England and the light they throw on the palao- geography of the time (10.45). This communication is an interim report of an investigation of the constituents of the pebbly horizons in the Lower Cretaceous beds of South England. More precise evidence than hitherto available, as to the nature of the rocks then undergoing denudation and the directions of the supply of detritus, is accumulating. In the Wealden beds of Dorset there is a highly distinctive suite of pebbles indicating the erosion of the metamorphic aureole of the Dartmoor Granite. This suite, except for one or two doubtful pebbles, has not been found in the Weald. ‘The resemblance between the pebbles from the north-west Weald, which are being examined by Dr. Wells and Mr. Gossling, and those from the Lower Cretaceous sands of Bedfordshire, Oxfordshire, Berkshire and Wiltshire indicates in part, at least, a common derivation from the London Platform. In this connection the distribution of the pebbles of silicified oolitic and dolomitic limestone is particularly significant. In east Kent, however, the pebble suite is of a somewhat different character. The many interesting types of pebbles found are described and inferences made as to their place of origin. Dr. S. M. K. Henperson.—The Dalradian Succession of the Southern Highlands (11.0). A brief account of the results of the study of current and graded bedding in the Leny Grits, Aberfoyle Slates and Ben Ledi Grits. ‘These three groups have generally been adopted as the youngest members of the Perth- shire Succession, and were included thus by Dr. Bailey in his Iltay Nappe. From Loch Lubnaig in the north-east to Loch Lomond in the south-west (Geological Survey, Sheet 38) current and graded bedding has always given the same evidence. The generalised dip is 60° to the north-west. The evidence shows that the Leny Grits to the south-east of the Aber- foyle Slates are upside down, and are younger than the latter, which they underlie. On the north-west side, the Ben Ledi Grits are also younger than the Aberfoyle Slates which they superimpose. On lithological grounds it seems reasonable to correlate the Leny and Ben Ledi Grits as one formation younger than the Aberfoyle Slates, the former being the under limb, and the latter the upper limb of a steeply overturned anticline. This would then be a structure comparable to the Carrick Castle Fold, an anticline closing to the south-east, in the Iltay Nappe of Bailey. The series of dislocations between the Leny Grits and the Highland. Border Rocks may, upon further investigation, prove to be the base of this large overfold of Dalradian rocks. SECTIONAL TRANSACTIONS.—C, 425 Dr. T. S. WestoLL.—The distribution of certain specialised Carboniferous bony fishes (11.15). The small fishes Haplolepis (Eurylepis Newberry) and Pyritocephalus Fritsch have been found to be closely related, and are probably descendants of Canobius; Pyritocephalus is much more specialised. Newberry’s E£. lineatus, from Linton, Ohio, is found to be almost identical with P. sculptus Fritsch from Nyiany, Czecho-Slovakia. This suggested a correlation of the two horizons, which was fully confirmed by palzobotanical evidence ; but it was later found that Teleopterina Berg, from Mazon Creek, Ill., and a fragmentary skull from Newsham, Northumberland, must also be referred to Pyritocephalus. The two genera occur at several horizons in the West- phalian and (?) basal Stephanian, namely : Newsham, Northumberland Flora E. Longton, Staffs Flora F. Mazon Creek, Illinois Flora G or G-H. Linton, Ohio \ Nyrany, Czecho-Slovakia | Flora H or H-I. (Palzobotanical horizons after Dix’s scheme.) These fishes are of great morphological interest as they approach Holo- steans in certain characters. Pyritocephalus has very specialised fenestra- tions in the skull-roof, perhaps due to the large eyeball, and both genera have peculiarities in their dermal bones. The distribution of these highly specialised small freshwater fishes raises important palazogeographical issues, while their recurrence, with cer- tain Amphibia, at different horizons indicates the existence of a well-marked vertebrate facies-fauna. Dr. J. B. Stmpson.—Fossil pollen in Scottish Furassic rocks (11.30). In the Jurassic strata that outcrop on the east coast of Sutherland, Scot- land, coal seams and carbonaceous layers are present at horizons in the Lower Lias, Estuarine Series, and Kimeridge Clay. | Examination of the microspore content of these coals has disclosed the presence in them of pollen of gymnospermous and dicotyledonous types as well as the spores of cryptogamic plants. The gymnosperms are represented by winged pollen grains such as we find in the Abietinez at the present day, and the variety of the forms already indicates a considerable degree of differentiation. The pollen of dicotyledonous types represent at least two living families— Magnoliacee and Nymphzacez.- In both families, too, more than one genus is present. The Magnoliacee are represented by one form similar to Magnolia, and another closely akin to Drimys. ‘The forms placed in the Nymphzacez show close affinities to the living genera Nelumbium and Castalia. The Nelumbium types show the characteristic bisymmetry of this class of pollen in polar view, and in other details also, resemble Tertiary and modern forms of the genus. The types identified as Castalia resemble the pollen of the tropical species of this genus. The presence of pollen of dicotyledons in these rocks is of special interest as being amongst the earliest fossil records of Angiosperms. 426 SECTIONAL TRANSACTIONS.—D. SECTION D.—ZOOLOGY. Thursday, August 18. PRESIDENTIAL ADpRESS by Dr. S. W. Kemp, F.R.S., on Oceanography and the fluctuations in the abundance of marine animals (10.0). (See p. 85.) Mr. C. F. Hicktinc.—Applications of our knowledge of the biology of British food fishes (11.0). The paper first describes the principles of the two most important types of fishing gear—namely, the drift net and the trawl, and points out the limitations of these gears when their results are used as samples of the populations of fish in the sea. But bearing these limitations in mind, the results of the fishing operations of the commercial fishing fleets may be used to keep a watch upon the state of the fish stocks available for capture. Moreover, these results, when interpreted in the light of the biology of the fish, may be used to predict the future course of the fisheries. ‘These points are illustrated by reference to the herring, haddock, cod, and hake. Mr. M. GranaM.—The rational exploitation of the fisheries (11.40). Statistics of trawl fisheries, such as those of haddock and plaice at Iceland, tend to show eventually that the response to increased fishing effort is, if anything, a decreased yield. : This phenomenon can be easily explained in terms of age-composition and growth-rate of stocks, which in many cases are available from investi- gations. The whole theory may be expressed by the ‘ logistic’ curve and its first derivative, which can be derived from the two assumptions (1) that the weight of stock that an area can support is limited, (2) that the rate of natural increase of a stock—reproduction plus growth minus natural mortality—is proportional to the difference of weight of the stock at a given moment and the limiting weight that the area will support. ‘This theory has been applied to the marketable species of the North Sea, taken together, in order to estimate the present waste of fishing effort and the maximum yield. Important implications are that unless the rate of fishing, including the mesh and form of nets and power of vessels, be controlled, the profit of undertakings is kept at a low value. Without control, gambler’s optimism in this industry tends to keep the rate of fishing as high as possible and the profit consequently at an extremely low level. Conversely, however, there is a possibility of a large profit in concerted action to avoid the expenditure entailed in keeping the rate of fishing high. A start has been made, in that most of the European countries concerned have signed a convention agreeing to use the minimum mesh allowed in Great Britain. ‘The investigations which show the efficacy of this provision are briefly described. Dr. J. B. Tair.—Significance of the physico-chemical environment in fisheries research (12.15). , AFTERNOON. Prof. 'T. W. M. CamMeron.—Some fish-carried Trematodes in Canada (2.15). - The great number of fresh-water lakes in Canada, its varied fish fauna and its variety of fish-eating mammals and birds, have made possible a large SECTIONAL 'TRANSACTIONS.—D. 427 variety of fish-carried parasites. Of these, the most varied are the Trema- toda, of which three species are discussed in this paper. Apophallus venustus (Heterophyidz) is a minute intestinal trematode parasitising numerous birds and mammals (including man). It is found in the lower valley of the river Ottawa, where its first host is the pulmonate snail, Goniobasis livescens, and its second hosts are numerous species of fresh-water fish. Cryptocotyle lingua (Heterophyidz), a sécond intestinal form, is confined to the eastern seaboard from the Labrador to the United States and has almost certainly been introduced from Europe. Its first host is Littorina littorea, and its second, various species of salt-water fish ; the adults occur in both birds and mammals and are serious parasites of foxes. Parametorchis nove- boracensis (Opisthorchidz) occurs from northern Quebec to Saskatchewan and is a serious liver-fluke of various mammals (including sledge dogs and man). Its first host appears to be a species of snail of the genus Amnicola ; its second is the fish called the Sucker, Catestomus commersoni. Mr. Homer A. Jack.—The zoological field stations of the United States (2.45). A zoological field station is an institution of approximate unitersity ranking which offers facilities for primarily field instruction and/or research in one or more of the zoological sciences, and is a separate administrative unit located in the field. The first zoological field station in the United States was the Anderson School of Natural History, founded in 1873 by Louis Agassiz. To-day there are almost sixty stations in the United States. These vary considerably in ecological location, administration, equipment, living conditions, type of students, investigators, and professors, and in available opportunities for instruction and research. This study was conducted to record and analyse material on field stations to aid: (1) prospective and actual students and investigators in the bio- logical sciences to select intelligently the stations most adapted to their needs; and (2) directors of stations in showing them how their fellow administrators are solving the problems attendant to the efficient organisa- tion and conduct of a field station. A plan is given for the interchange of students, investigators, and professors between field stations in the United States and other countries. This could not only enrich the zoological sciences, but also strengthen international understanding. Miss G. E. PickForD.—The Vampyromorpha—a new order of Dibranchiate Cephalopods (3.15). Since their discovery by Chun the Vampyroteuthide have been regarded as aberrant if rather primitive Octopoda. Recognised as Octopodan characters were the eight conspicuous arms united by a deep web and the apparently normal union of head with mantle. Outstanding as primitive characters were the fins, the arrangement of suckers and cirri on the arms and the lack of condensation of the central nervous system. Specialised features, such as black pigmentation, phosphorescent organs and peculiar tentacles lodged in pockets of the web, could be regarded as adaptations to a bathypelagic life. Robson first recognised the Vampyromorpha as a sub-order distinct from other cirrate armed Octopoda. Two well-preserved, but unfortunately immature, female specimens in the Bingham Oceanographic Collection of Yale University have provided material for a detailed anatomical study. It is possible now to state definitely that they exhibit no positive characters which would justify retention as a sub-order of the Octopoda. Although similar to that of Octopoda, the 428 SECTIONAL TRANSACTIONS.—D. separate origin of the genital artery and the orientation of the heart must be regarded as characters ancestral to Octopods and Decapods alike. The spacious ccelom, gill structure, funnel valves, and other characters which apparently relate the Vampyromorphs to living Decapods are also ancestral rather than definitively Decapodan in nature. The retractile filaments undoubtedly represent modified arms, but since it is the second rather than the fourth arm pair which is thus modified one cannot postulate relations with living Decapods. The structure of the shell with its broad pro-ostracum resembles that of Liassic teuthoideans and the direct articulation of the fin bases upon the shell is a primitive feature postulated by Naef but not found in any adult living form. It is evident that the Vampyromorpha represent a distinct and ancient type of dibranchiate Cephalopod. ‘They should be treated as a group of equivalent rank with Octopods and Decapods. Mrs. M. D. BrInDLEY.—The succession of Hemiptera-Heteroptera in the afforested areas of Breckland (3.45). Breckland is the name given to a well-defined area in the western parts of Norfolk and Suffolk. It is characterised by tracts of sandy heath with a distinctive vegetation which is conditioned primarily by the soil and the relatively dry climate. During the last sixteen years, about 50,000 acres of this land have been afforested with conifers, and the planting has greatly modified the flora and fauna. This communication, after a short general description of the region, deals with the change as it has affected the insect group Heteroptera in a selected area over a period of seven years, covering the transition from a heath to a conifer-dwelling type of population. At present three elements can be distinguished in the Heteroptera fauna, viz. (i) widely distributed, usually polyphagous forms, (ii) species peculiar to heathlands, and (iii) forms whose host-plants are conifers. By gradual infiltration, as the trees grow up, the third group becomes dominant. The adjustment of the different species to the changing environment, and the influence of the age and size of the plantations on distribution are discussed. Prof. J. STANLEY GARDINER, F.R.S.—Wicken Fen (4.15). EXHIBITION illustrating the Genetics and chemistry of plant and animal pigments. One of the characters of plants and animals most frequently used in genetical investigations is colour. Until recently separation of colour types has depended solely on visual comparisons, which may sometimes be mis- leading and are always inadequate since they represent only a first analysis. Further understanding of the developmental processes involved requires an analysis of the chemical nature and physical state of the pigments responsible. This has become possible in some cases. The exhibit was designed to illustrate various phases in the development of this aspect of physiological genetics from purely descriptive genetics. The analysis has gone farthest in the case of flower pigments, especially the anthocyanins and anthoxanthins. With these gene action can be ex- amined, for the first time, in its fundamental sense, namely as governing simple chemical changes, such as oxidation, reduction, methylation or. glycoside formation. In other cases, as in Drosophila, the budgerigar and the clover chlorophyll deficients, we know something about which pigments are affected but nothing of the nature of the changes. SECTIONAL TRANSACTIONS.—D. 429 Mr. W. J. C. Lawrence and Mr. J. R. Price.—Flower pigments. THe CHEMICAL BASIS OF FLOWER COLOUR. The substances responsible for flower colour may be divided into two classes, sap-soluble and non-sap-soluble. The sap-soluble pigments comprise the anthocyanins, anthoxanthins and certain nitrogenous substances. The Anthocyanins are the most important flower colouring matters, and are responsible for scarlet, red and blue colours. They occur as glycosides, that is, they are compound molecules formed by the union of the true colouring matter with one or more molecules of a sugar. The colour-producing part of the anthocyanin molecule, known as the anthocyanidin, may be derived from one of three main structures—pelar- gonidin, cyanidin and delphinidin—which differ only in the number of hydroxyl groups (—OH) in the phenyl ring : Cl. /OH aan OH =O) 5 sHO!= -OH ‘OH -OH oH Pelargonidin Cyanidin Delphinidin As the formule show, cyanidin has one and delphinidin two more oxygen atoms in the molecule than pelargonidin. These differences represent one of the principal factors upon which variation in flower colour depends, since an increase in the number of oxygen atoms (in the form of hydroxyl groups) results in a marked increase in blueness of tone. This is illustrated in the first part of the exhibit. As mentioned above, the anthocyanins occur as compounds involving one ormore moleculesofasugar. Of these sugar molecules one is always attached at the 3 position ; if there is a second sugar molecule it may be attached either directly to the first one or it may unite with the anthocyanidin in a different position, at 5. Hence there are two classes of glycosides: (a) those with one or two sugar molecules attached at position 3, and (b) those with sugar molecules at both 3 and 5. ‘These two classes are visibly different in colour and constitute another important factor in flower colour variation, the 3 : 5-diglycosides being bluer than the corresponding 3-type. A third variable involving structural difference in the anthocyanins is the existence or otherwise of methylated hydroxyl groups, where the hydrogen atom of a hydroxyl group has been replaced by a methyl (CH;) radicle. This results in an increase in redness. As arule the only hydroxyl groups methylated are those at positions 3’ and 5’; that at 4’ is never methylated. Thus there is one methyl ether of cyanidin and there are two of delphinidin (3’-mono- and 3’ : 5’-di-). So far three factors influencing the colour of anthocyanins have been dealt with, namely : (a) The number of hydroxyl groups in the molecule. (b) The position of attachment of the sugar molecules. (c) The methylation of hydroxyl groups. Combinations of these three give rise to twelve anthocyanins, differing slightly in colour and covering a wide range from scarlet to purple. 430 SECTIONAL TRANSACTIONS.—D. These factors are all dependent upon structural changes in the antho- cyanin molecule, that is, the differences are internal. However, conditions external to the molecule may also affect the colour of the anthocyanins. The most important of these is a phenomenon known as copigmentation, which will be referred to in connection with the anthoxanthins. Secondly, modification of the flower colour can be brought about by variation in the pH of the cell sap, the colour becoming bluer as the pu is increased. The Anthoxanthins—The substances included under this heading are closely related chemically to the anthocyanins, but differ in colour, ranging from pale ivory to deep yellow. Like the anthocyanins, they are sap soluble and usually occur as glycosides. Structural variation is greater than in the case of the anthocyanidins, but the majority are analogous and fall into two classes, the flavones and flavonols, which differ in that the flavones have no hydroxyl group at position 3. /OH HO- -OH HO- -OH -OH 1 “ ' “ , | OHO OH O Apigenin - a flavone. Quercetin - a flavonol. Increase in the number of hydroxyl groups present in an anthocyanidin molecule results in increased blueness. A similar effect is manifest in the flavones and flavonols, which become more yellow. There are four ways in which the anthoxanthins are concerned in flower colour : (a) In flowers which have no anthocyanin they may be directly responsible for some or all of the colour. (b) If a yellow anthoxanthin occurs together with an anthocyanin, the resultant colour is a blend of the two. (c) In the presence of anthocyanins, ivory anthoxanthins, as would be expected, do not contribute directly to the colour ; nevertheless they may be of great importance on account of their ‘ copigmenting ’ action. When present in the same solution as an anthocyanin they combine loosely, in some way as yet unknown, with the anthocyanin, to give a much bluer colour. The effect is very marked, and flowers with a copigmented cyanidin derivative may appear bluer than those containing an uncopigmented delphinidin glycoside. It is probably not an exaggeration to say that upwards of 70% of garden flowers are copigmented, to some. extent at least. The degree of copigmentation varies with the nature of. the anthocyanin, delphinidin being most readily copigmented and pelargonidin derivatives least. It also varies with the nature of the flavone or flavonol. There is no exact information on this point, but observations show tha yellow anthoxanthins do not generally behave as copigments. _ ; (d) It has been’ pointed out that there is a close relationship between anthocyanins and anthoxanthins, as is shown by inspection of their respec- tive formule. Therefore their syntheses in the plant might be expected to follow similar lines. Evidence in favour of this suggests that the anthocyanins and anthoxanthins are formed from the same starting material, which may be limited in quantity. This results in competition between the two, and if most of the source is utilised in the synthesis of one pigment, then of necessity less of the other is produced. For example, the presence of much anthoxanthin may lead to almost complete suppression of antho- cyanin, resulting in delicately flushed flowers. SECTIONAL TRANSACTIONS.—D. 431 Plastid Pigments—The plastid colouring matters comprise a number of yellow or orange substances such as xanthophyll or carotin, which are insoluble in the cell sap and are quite independent of the sap-soluble colouring matters. In the absence of anthocyanins they are either solely responsible for flower colour, or are supplementary to the yellow anthoxanthins. In the presence of anthocyanins their effect is purely that of a background ; thus in the tulip the introduction of yellow plastid pigment changes the colour from pink, crimson or purple to orange, scarlet or brown respectively. The first part of the exhibit includes examples of the various types of pigments and shows the effect on anthocyanin colour of variation in the number of hydroxyl groups, glycosidal type, methylation of hydroxyl groups and copigmentation. Mixture and background effects of antho- cyanins with anthoxanthins and plastids are also shown. In addition there are three of the rarer flower colouring matters. Gesnerin from Gesnera species is unusual in that it has no hydroxyl group in the 3 position. Celosia and Iresine contain nitrogenous pigments similar to that found in beetroot. Flowers of Papaver nudicaule also contain a introgenous colouring matter, but of a different type. THE GENETICS OF FLOWER COLOUR. Flower colour variation has been studied genetically for many years, but until recently, as pointed out earlier, the only possible criterion of colour types was the visual one. The result was a chaotic mass of informa- tion about the inheritance of flower colour, which was only disentangled when the means by which variation is brought about were recognised. The position now is that nearly all of the factors listed in the table are known to be controlled by single genes. TABLE. Variation in flower colour is brought about by one or more of the following factors. Changes are shown in one direction only ; the reverse may be inferred. i. Increase in number of hydroxyl groups | Increased blueness. il tas ii. Alteration from 3- to 3 : 5- sugar types 5 ee. og eee ° S-3 iii. Methylation of one or more hydroxy] | g 3 groups é ; ’ : “| bs redness. 3) iv. Increase in pH f d 3 a 5 blueness. v. Copigmentation ; : : Sol : is Increased yellowness. Alteration of back- vi. Increase in number of hydroxyl groups viii. Interaction of anthocyanins and antho- xanthins ; ' F re) & ground. ee = Change in copigment b:| g effect. a vii. Partial suppression of one or both types. Alteration in nature of plastid pigment Yellow becomes orange. Alteration of back- ground. 432 SECTIONAL 'TRANSACTIONS.—D. In addition there are genes which govern the presence or absence of antho- cyanins, anthoxanthins or plastid pigments, and genes which produce a general or local intensification or dilution of colour. The biochemical value of this work lies in the fact that single genes have been shown to control simple chemical reactions, such as oxidation resulting in the introduction of a hydroxyl group, and glucoside formation. In sweet peas two whites crossed together may give coloured progeny, each parent introducing a different gene necessary for anthocyanin formation. Similarly in maize, thirteen dominant genes are necessary for the production of chlorophyll. It seems then that each stage in the synthesis of any plant product is governed by a single gene, and the geneticist is therefore able to separate the metabolic processes into their different stages. ‘This should make it possible for the biochemist to find out what the reactions are and how genes bring them about. The second part of the exhibit is designed to show that the differences in flower colour are controlled by single genes which conform to the Mendelian laws of inheritance. Examples are given of the inheritance of alternative pairs of gene-controlled characters : (a) Anthocyanin—no anthocyanin. 3:1 ratio |(6) Anthoxanthin copigment—no copigment. in F, |(c) Delphinidin (oxidation)—cyanidin (no oxidation). (d) Higher pH—lower pu. I :1 ratio. idee (e) Diglycoside—monoglycoside. cross These five show complete dominance of the first character, that is, the heterozygote is indistinguishable from the homozygous dominant—one gene is doing the work of two. Incomplete dominance is shown in the cross red X white Antirrhinum; the first generation is intermediate (pink), and in the second generation a ratio 1 red : 2 pinks : 1 white is obtained. The red and white breed true, but the pinks always throw red, pink and white. In the cross purple x scarlet Verbena independent segregation of two pairs of characters is shown, with recombination in the second generation resulting in the production of two new colour types. For example, pelar- gonidin 3: 5-diglycoside is produced by bringing together the gene for diglycoside carried by one plant with that for pelargonidin from the other parent. : In a similar manner it is possible to obtain an anthocyanin different from that of either of the parents. The salmon Streptocarpus carries a gene for methylation, but this gene has no effect when the anthocyanin is derived from pelargonidin. On crossing with a variety containing cyanidin from which the methylation gene is absent, the flowers of the progeny contain a methylated cyanidin derivative. The segregation of three pairs of factors is shown in the second generation from the cross blue