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fl. 73. 







TORONTO— 1924 

AUGUST 6-13 







Officers and Council, 1924-25 v 

Local Officers, Toronto, 1924 vii 

Sections and Sectional Officers, Toronto, 1924 viii 

Annual Meetings : Places and Dates, Presidents, Attendances, 
Receipts, Sums paid on account of Grants for Scientific 
Purposes (1831-1924) x 

Report of the Council to the General Committee (1923-24) xiv 

British Association Exhibitions xviii 

General Meetings, Public Lectures, etc., at Toronto xviii 

General Treasurer's Account (1923-24) xxi 

Research Committees (1924-25) xxvi 

Cairo Fund xxxi 

Resolutions and Recommendations (Toronto Meeting) xxxii 

The Presidential Address : 

Prevention of Disease. By Major-Gen. Sir D. Bruce 1 

Sectional Presidents' Addresses : 

A. — The Analysis of Crystal Structure by X-Rays. By Prof. SirW. H. 

Bragg 34 

B. — Chemistry and the State. By Sir Robert Robertson 53 

C. — Geology in the Service of Man. By Prof. W. W. Watts 89 

D. — Construction and Control in Animal Life. By Prof. F. W. Gamble 109 

E. — Liter-racial Problems and White Colonization in the Tropics. 

By Prof. J. W. Gregory 125 

F. — A Retrospect of Free Trade Doctrine. By Sir W. Ashley .... 148 

G. — A Hundred Years of Electrical Engineering. By Prof. G. W. 0. 

Howe 178 

H. — Health and Physique through the Centuries. By Dr. F. C. 

Shrubsall 190 

I.-^Progress and Prospects in Chemotherapy. By Dr. H. H. Dale . . 211 

A 'J 



J. — Purposive Striving. By Prof. W. McDougall 226 

K. — Physiological Aspects of Parasitism. By Prof. V. H. Blackman 233 
L. — Academic Freedom in Universities. By Principal E. Bakker . . 247 
M. — Present-day Problems in Crop Production. By Sir J. Russell 256 

Reports on the State of Science, etc 270 

Sectional Transactions 358 

References to Publication of Communications to the Sections .... 464 

Official Journeys 470 

Conference of Delegates op Corresponding Societies 490 

List of Papers, 1923, on Zoology, Botany, and Prehistoric 

Archeology of the British Isles. By T. Sheppard 494 

Index 555 

§ritislj l^ssariation for l^t |.bbanctnicnt 

0f Sri^na, 




Major Gen. Sir David Bruce, A.M.S., K.C.B., D.Sc, LL.D., F.R.S. 

Professor Horace Lamb, D.Sc, LL.D., F.R.S. 


H.E. the Governor-General op 
Canada (Rt. Hon. Lord Byng of 
~ ~ , G.C.M.G.). 

(Col. Henry Cock- 

ViMY, G.C.B 
His Hon.' the 

of Ontario 

Rt. Hon. the Prime Minister of 

Canada (W. L. Mackenzie King, 

C.M.G., LL.D.). 
The Hon. the Speaker of the House 

OF Commons (Hon. Rodolphe 

The Hon. the High Commissioner for 

Canada (P. C. Larkin). 
The Hon. the Prime Minister and 

Minister of Education, Ontario 

(G. Howard Ferguson, LL.B.). 
The Chancei.lor of the University 

OF Toronto (Hon. Sir William 

MuLOCK, K.C.M.G., K.C., LL.D.). 


H.R.H. Princess Beatrice (Governor 
and Captain-General of the Isle of 

The Lord-Lieutenant of the County 
OF Hants (Major-Gen. the Rt. Hon. 
J. E. B. Seely, C.B., C.M.G., 
D.S.O., T.D., M.P.). 

His Worship the Mayor of South- 

The Lord Bishop or Winchester (the 
Rt. Rev. F. T. Woods, D.D.). 

The Lord Bishop of Portsmouth (the 
Rt. Rev. W. T. Cotter). 

The Rt. Hon. Lord Swaythling. 

Lord Apsley, D.S.O., M.C., M.P. 

Brig. -Gen. the Rt. Hon. Lord Mon- 
tagu of Beaulieu, K.C.I.E., C.S.I., 
F.Z.S., V.D., D.L. 

His Worship the Mayor of Toronto 

(W. W. HILTZ). 

The Chairman of the Board of 

Governors, University of Toronto 

(Rev. Canon H. J. Cody, B.D., 

The President of the University 

OF Toronto (Sir Robert Falconer, 

K.C.M.G., D.Litt., LL.D.). 
The President of the Royal Canadian 

Institute (Prof. J. C. Fields, 

Ph.D., F.R.S.). 
The President of the Canadian 

National Railways (Sir Henry W. 

Thornton, K.B.E.). 
The President of the Canadian 

Pacific Railway (E. W. Beatty). 
The Chairman of the Local General 

and Executive Committee (Prof. 

J. C. McLennan, O.B.E., Ph.D., 

D.Sc, LL.D., F.R.S.). 

Col. E. K. Perkins, C.B.E., V.D., 

Cooper, Bart., V.D., 
W. Ashley, 

M.P., D.L. 

Sir George A. 

Lieut. -Col. Wilfrid 

M.P., D.L. 
Sir Wyndham Portal, Bart., F.S.A., 

The President of the University 

College of Southampton (C. G. 

Montefiore, M.A., D.D.). 
The Principal of the University 

College of Southampton (Kenneth 

H. Vickers, M.A.). 
The Director-General of the 

Ordnance Survey (Col. E. M. Jack, 

C.M.G., D.S.O.). 
Col. Sir C. F. Close, K.B.E., C.M.G., 




E. H. Ghiffiths, Sc.D., D.Sc, LL.D., F.R.S. 


Professor J. L. Myres, O.B.E., M.A., 
D.Sc, F.S.A., F.B.A. 

F. E. Smith, C.B.E., F.R.S. 


0. J. R. HowAETH, O.B.E., M.A., Burlington House, London, W. 1. 


R. C. Anderson, F.S.A. ; Prof. W. R. Sherriffs, D.Sc. ; F. Woolley. 


J. Reynolds Hole. 


Prof. W. H. Ashworth, F.R.S. 

Dr. F. W. Aston, F.R.S. 

J. Barcroft, F.R.S. 

Principal E. Barker. 

Sir W. H. Beveridge, K.C.B., F.R.S. 

Rt. Hon. Lord Bledisloe, K.B.E. 

Prof. E. G. CoKEE, F.R.S. 

Professor W. Dalby, F.R.S. 

Professor C. H. Desch, F.R.S. 

E. N. Fallaize. 

Dr. J. S. Flett, O.B.E., F.R.S. 

Professor H. J. Fleure. 

Professor A. Fowler, F.R.S. 


Sir Daniel Hall, K.C.B., F.R.S. 
C. T. Heycock, F.R.S. 
Sir T. H. Holland, K.C.M.G., F.R.S. 
Sir J. Scott Keltib. 
Professor A. W. Kirkaldy. 
Dr. P. Chalmers Mitchell, C.B.E., 
F T? S 

Dr.'c! S. Myers, F.R.S. 
Professor A. W. Porter, F.R.S. 
Professor A. 0. Seward, F.R.S. 
Dr. F. C. Sheubsall. 
Prof. A. Smithells, C.M.G., F.R.S. 
A. G. Tansley, F.R.S. 


The Trustees, 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, past Assistant General 
Secretaries, and the Local Treasurers and Local Secretaries for the Annual 
Meetings immediately past and ensuing. 

Major P. A. MacMahon, D.Sc, 
LL.D., F.R.S. 

Hon. Sir Charles A 


Sir Arthur Evans, 
F.R.S., F.S.A. 
Parsons,' K.C.B., LL.D., D.Sc, F.R.S. 

M.A., LL.D., 


Rt. Hon. the Earl of Balfour, O.M., 

Sir E. Ray Lankester, K.C.B., F.R.S. 
Sir Francis Darwin, F.R.S. 
Sir J. J. Thompson, O.M., F.R.S. 
Sir E. Sharpey Schafee, F.R.S. 
Sir Oliver Lodge, F.R.S. 
Professor W. Batesox, F.R.S. 

Sir Arthue Schuster, F.R.S. 

Sir Aethue Evans, F.R.S. 

Hon. Sir C. A. Parsons, K.C.B., 

Sir T. Edwaed Thoepe, C.B., F.R.S. 
Prof. Sir C. S. Sherrington, G.B.E., 



Sir E. Sharpey Schafer, F.R.S. 
Dr. D. H. Scott, F.R.S. 
Dr. J. G. Garson. 

Major P, A. MacMahon, F.R.S. 
Professor H. H. Turner, F.R.S. 

Professor A. Bowley. 



I Professor A. 

W. Kirkaldy. 





Professor J. C. McLennan, F.R.S. 
(ill whose absence Prof. H. Wasteneys was Acting Chairman). 


Professor J. C. Fields, F.R.S. 
Professor J. J. R. Macleod, M.B., Ch.B., D.P.H. 

Major J. M. Mood, O.B.E., M.C. 


F. A. Moure, Mus.Doc. 


The following were Chairmen of Associate Committees for arrange- 
ments in Toronto : — 






Meeting Rooms 

Signs and Messengers 

Finance and Transportation 

Exhibition of Scientific Apparatus 

Printing ..... 

Prof. W. A. Parks. 
H. V. F. Jones. 
Sir Robert Falconer. 
Dr. W. G. Miller. 
Prof. H. Wasteneys. 

Prof. J. R. COCKBURN. 

Prof. Allcut. 
D. B. Hanna. 
Prof. E. F. Burton. 
R. J. Hamilton. 


District Committees were formed to collaborate with the Executive 
in Toronto in making local arrangements in connection with the Meeting. 
The Chairmen of these Committees were as follows : — 

Halifax . . Pres. A. Stanley Mackenzie, Ph.D., D.C.L., Dalhousie 

Quebec . . Hon. Cyrille Delage. 

Montreal . . PrincipalSirARTHURCuRRiE,G.C.M.G.,K.C.B.,LL.D.,McGill 

Ottawa . . . Dr. W. H. Collins, Director, Canadian Geological Survey. 

Kingston . . Prof. A. L. Clark, Ph.D., Queen's University. 

Guelph . . . Pres. J. B. Reynolds, M.A., Ontario Agricultural College. 

London, Ont. . . W. S. Fox, Ph.D., Dean of the Faculty of Arts, Western 

Port Arthur and Fort William F. H. Keefer, M.P.P. 
Winnipeg . . Prof. C. H. O'Donoghue, University of Manitoba. 
Regina . . . Hon. Sir Frederick Haultain, Chief Justice of Saskatchewan. 
Saskatoon . . Pres. Walter C. Murray, LL.D., University of Saskatchewan. 
Edmonton . . Pres. Henry Marshall Tory, D.Sc, LL.D., University of 

Calgary . . . Dr. J. M. Scott. 

Vancouver . . Pres. L. S. Klinck, D.Sc, University of British Columbia. 
Victoria . . Prof. P. H. Elliott, M.Sc, Victoria College. 



P^^sident.^SiT William Bragg, K.B.E., F.R.S. 
Vice-President^.—Vroi. A. S. Eve, C.B.E., F.R.S. ; Prof. J. C. Fields, F.R.S. ; 

Prof. J. C. McLennan, O.B.E., F.R.S.; Prof. J. S. Plaskett, F.R.S.; 

Sir F. Stupart. 
Recorder. — Prof, A. 0. Rankine. 
Secretaries.- — M. A. Giblett, Prof. H. R. Hasse, J. Jackson, Prof. A. M. 


President. — ^Sir Robert Robertson, K.B.E., F.R.S. 
Vice-Presidents.— Proi. F. G. Donnan, C.B.E., F.R.S.; Prof. Lash Miller; 

Dr. N. V. SiDGwicK, O.B.E., F.R.S. 
Recorder.— Froi. C. H. Desch, F.R.S. 
Secretary. — Dr. E. K. Rideal. 


President.— Fi'oi. W. W. W.\tts, F.R.S. 

Vice-Presidents.— 'Proi. C. Camsall ; Prof. A. P. Coleman, F.R.S.; W. H. 
Collins; Dr. Gertrude Elles ; Sir T. H. Holland, K.C.S.I., F.R.S.; 
J. McLeish; Dr. W. G. Miller; Prof. W. A. Parks; J. B. Tyrrell; 
Prof. T. L. Walker ; Dr. David White ; the Deputy Ministers, Depts. of 
Mines, Canada and Ontario; the Presidents of the Geological Section, 
Royal Society of Canada, and of the Canadian Institute of Mining and 

Reaorder.—PToi. W. T. Gordon. 

Secretary. — Prof. G. Hickling. 

President.— Proi. F. W. Gamble, F.R.S. 
Vice-Presidents. — Prof. J. H. Ashworth, F.R.S.; Prof. B. A. Bensley ; Prof, 

A. G. Huntsman ; Prof. A. Willet. 
Recorder. — F. Balfour Browne. 
Secretary. — Prof. W. J. Dakin. 

President.— Proi. J. W. Gregory, F.R.S. 
Vice-Presidents. — Dr. H. M. Ami; Dr. Vaughan Cornish; Dr. E. G. Deville; 

Dr. Marion I. Newbigin/ James White. 
Recorder. — ^Dr. R. N. Rudmose Brown. 
Secretaries.— W. H. Barker, J. Bartholomew. 

President. — Sir William Ashley. 

Vice-Presidents. — Sir John Aird ; Sir William Beveridge, K.C.B. ; Prof. 
Edwin Cannan ; Prof. R. M. MacIver ; Prof. James Mavor ; J. Staples. 
Recorder.- — Prof. H. M. Hallsworth. 
Secretary. — R. B. Forrester. 

President. — Prof. G. W. 0. Howe. 

Vice-Presidents. — Sir Henry Fowler, K.B.E. ; Dean C. H. Mitchell. 
Recorder. — Prof. F. C. Lea. 
Secretaries. — Prof. A. Robertson, J. S. Wilson. 



President. — Dr. F. C. Shrubsall. 
Vice-Presidents.— U. Balfour, F.R.S. ; Dr. A. C. Haddon, F.R.S. ; Dr. Alis 

Hedlicka; Prof. J. P. McMurrich; Sir Bertram Windle, F.R.S. 
Recorder. — E. N. Fallaize. 
Secretaries. — Miss R. M. Fleming, Dr. A. Low. 

President.— Br. H. H. Dale, C.B.E., F.R.S. 
Vice-Presidents.— Proi. J. J. R. Macleod, F.R.S. ; Prof. G. H. F. Nuttall, 

Recorder. — ^Prof. C. Lovatt Evans. 
Secretaries.— Br. J. H. Burn, Prof. E. P. Cathcart, C.B.E., F.R.S. 

Preside?! «.— Prof. W. McDougall, F.R.S. 
Vice-Presidents. — Prof. E. A. Bott ; Prof. G. S. Brett; Dr. 0. Burt; Prof. 

Cattell ; Dr. 0. S. Myers. 
Recorder. — Dr. Ll. Wynn Jones. 
Secretaries. — R. J. Bartlett, Dr. Shepherd Dawson. 

President.— Proi. V. H. Blackman, F.R.S. 
Vice-Presidents. — Prof. H. H. Dixon; frof. J. H. Faull; Prof. R. Ruggles 

Gates; Dr. C. D. Howe; Prof. F. J. Lewis; Prof. F. E. Lloyd; Prof. 

J. H. Priestley; Dr. A. B. Rendle, F.R.S.; Miss E. R. Saunders. 
Recorder. — Prof. J. McLean Thompson. 
Secretary. — Dr. W. Robinson. 

President. — Principal Ernest Barker. 

Vice-Presidents. — Sir Robert Falconer, K.C.M.G. ; Dean W. Pakenham. 
Recorder. — C. E. Browne. 
Secretary. — Dr. Lilian Clarke. 


President. — Sir John Russell, F.R.S. 

Vice-Presidents. — Dr. C. Crowther; Dr. F. C. Harrison; Hon. J. S. Martin; 

Pres. J. B. Reynolds; Dr. F. T. Shutt. 
Recorder. — Dr. G. Scott Robertson. 
Secretary. — T. S. Dymond. 

Sort ion. 




























J. C. McLennan. 
Lash Miller 

A. P. Coleman 

B. A. Bensley 
White . 

R. M. MacIver 

C. H. Mitchell 
J. P. McMurrich 
J. J. R. Macleod 
G. S. Brett . 
J. H. Faull . 
W. Pakenham 
J. B. Reynolds 



. Prof. E. F. Burton. 

. Prof. E. G. R. Ardagh. 

. Prof. E. S. Moore. 

. Prof. E. M. Walker. 

. R. Douglas. 

. Prof. C. R. Fay. 

. Prof. T. R. Loudon. 

. Dr. Edward Sapir. 

. Prof. H. Wasteneys. 

. Prof. E. A. Bott. 

. Prof. R. B. Thomson, 

. Prof. P. Sandifoed. 

. A. M. Porter. 



Date of Meeting 

Where held 


Old Life 

New Life 

1831, Sept. 27 

1832, June 19 

1833, June 25 

1834, Sept. 8 

1835, Aug. 10 

1836, Aug. 22 

1837, Sept. 11 

1838, Aug. 10 

1839, Aug. 26 

1840, Sept. 17 

1841, July 20 

1842, June 23 

1843, Aug. 17 

1844, Sept. 26 

1845, June 19 

1848, Sept. 10 

1847, June 23 

1848, Aug. 9 

1849, Sept. 12 

1860, July 21 

1861, July 2 .. . 


Viscount Milton, D.O.L., F.R.S 

The Rev. W. Buckland, F.R.S 

The Rev. A. Sedgwick, F.R.S 

Sir T. M. Brisbane, D.O.L., F.R.S. ... 
The Rev. Provost Lloyd,LL.D., F.R.S. 
The Marquis of Lansdowne, 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.R.S. 

The Rev. W. Whewell, F.R.S 

The Lord Francis Egerton, F.G.S. ... 

The Earl of Rosse, F.R.S 

The Rev. G. Peacock, D.D., F.R.S. ... 
Sir John F. W. Herschel, Bart., F.R.S. 
Sir Roderick I.Murchison,Bart.,F.R.S. 
Sir Robert H. Inglis, Bart., F.R.S. ... 
TheMarquis of Northampton,Pres.R.S. 
The Rev. T. R. Robinson, D.D., F.R.S. 

Sir David Brewster, K.H., F.R.S 

G. B. Airy, Astronomer Royal, F.R.S. 

Lieut.-General Sabine, F.R.S 

William Hopkins, F.R.S 

The Earl of Harrowby, F.R.S 

The Duke of Argyll, F.R.S 

Prof. 0. G. B.Daubeny, M.D., F.R.S.... 

The Rev. H. Lloyd, D.D., F.R.S 

Richard Owen, M.D., D.O.L., F.R.S.... 
H.R.H. The Prince Consort 








I 20 







Newcastle-on-Tyne. . . 













1862, Sept. 1 . . 
1853, Sept. 3 . 

1864, Sept. 20 

1865, Sept. 12 

1856, Aug. 6 

1867, Aug. 26 

1868, Sept. 22 

1859, Sept. 14 

1860, June 27 

1861, Sept. 4 

1862, Oct. 1 

1863, AU2. 26 

1864, Sept. 13 

1865, Sept. 6 

1866, Aug. 22 

1867, Sept. 4 

1868, Aug. 19 

1869, Aug. 18 

1870, Sept. 14 

1871, Aug. 2 

1872, Aug. 14 

1873, Sept. 17 

1874, Aug. 19 

1875, Aug. 25 

1876, Sept. 6 

1877, Aug. 15 

1878, Aug. 14 

1879, Aug. 20 

1880, Aug. 25 ... 

1881, Aug. 31 ... 

1882, Aug. 23 . 

1883, Sept. 19 ... 

1884, Aug. 27 . 

1885, Sept. 9 

1886, Sept. 1 ... . 

1887, Aug. 31... 

1888, Sept. 5 .... 

1889, Sept. 11 

1890, Sept. 3 

1891, Aug. 19...];: 

1892, Aug. 3 

1893, Sept. 13 

1894, Aug. 8 ... 

1895, Sept. 11 
189S,Sept. ]6 . 

1897, Aug. 18 

1898, Sept. 7 

1899, Sept. 13.!!!" 










The Lord Wrottesley, M.A., F.R.S. ... 

William Fairbairn, LL.D., F.R.S 

The Rev. Professor WiUis,M.A.,F.R.S. 
Sir William G. Armstrong.O.B., F.R.S. 
Sir Charles Lyell, Bart., M.A., F.R.S. 
Prof. J. Phillips, M.A., LL.D., F.R.S. 

Waiiam R. Grove, Q.O., F.R.S 

The Duke of Buocleuch, K.O.B.,F.R.S. 

Dr. Joseph D. Hooker, F.R.S 

Prof. G. G. Stokes, D.O.L., F.R.S 

Prof. T. H. Huxley, LL.D., F.R.S. ... 
Prof. Sir W. Thomson, LL.D., F.R.S. 

Dr. W. B. Carpenter, F.R.S 

Prof. A. W. Williamson, F.R.S 

Prof. J. Tyndall, LL.D.,F.R.S 

Sir John Hawkshaw, F.R.S 

Prof. T. Andrews, M.D., F.R.S 

Prof. A. Thomson, M.D., F.R.S 

W. Spottiswoode, M.A., F.R.S 

Prof. G. J. AUman, M.D., F.R.S. ... 

A. 0. Ramsay, LL.D., F.R.S 

Sir John Lubbock, Bart., FJl.S. ... 

Dr. 0. W. Siemens, F.R.S 

Prof. A. Cayley, D.O.L., F.R.S 

Prof. Lord Raylei gh, F.R.S 

Sir Lyon Playfair, K.C.B.,F.R.S.... 

Sir J. W. Dawson, C.M.G., FJl.S. .. 

1 Sir H. B. Roscoe, D.O.L., F.R.S. ... 

Sir F. J. Bramwell, F.R.S 

Prof. W. H. Flower, C.B., FJl.S 

Sir F. A. Abel, C.B., F.R.S 

Dr. W. Huggins, F.R.S 

Sir A. GeiMe, LL.D., F.R.S 

Prof. J. S. Burden Sanderson, F.R.S 
The Marquis of SaIisbury,K.G.,FJl.S 
Sir Douglas Galton, K.O.B., FJl.S. ... 
Sir Joseph Lister, Bart., Pres. R.S. .. 

Sir John Evans, K.C.B., F.R.S 

Sir W. Orookes, F.R.S 

Sir Michael Foster, K.C.B., Sec.R.S... 



Newcastle-on-Tyne. . . 



































* Ladies were not admitted by purchased tickets until 1843. f Tickets of Admission to Sections only. 

[Continued onp.xn. 












Sums paid 
on account 
of Grants 




for Scientific 






















































922 12 6 









932 2 2 









1595 11 








1546 16 4 








1235 10 11 








1449 17 8 








1665 10 2 








981 12 8 








831 9 9 








685 16 








208 6 4 









276 1 8 









169 19 6 









345 18 









391 9 7 









304 6 7 


















380 19 7 









480 16 4 









734 13 9 









507 15 4 









618 18 2 









684 11 1 









766 19 6 









nil 6 10 









1293 16 6 









1608 3 10 









1289 15 8 









1691 7 10 









1750 13 4 









1739 4 




































1472 2 6 



























1151 16 


















1092 4 2 









1128 9 7 









725 16 6 









1080 11 11 









731 7 7 









476 8 1 









1126 1 11 









1083 3 3 









1173 4 


















995 6 









1186 18 









1511 5 









1417 11 









789 16 8 









1029 10 









864 10 









907 15 6 









583 15 6 









977 16 5 









1104 6 1 









1059 10 8 


















1430 14 2 


X Including Ladies. § Fellowsofthe American Association wereadmitted as Hon. Members for this Meeting 

\_Contimted on p. xiii. 



TahU of 

Date of Meeting 

1900, Sept. 6 .... 

1901, Sept. 11.... 
1903, Sept. 10.... 

1903, Sept. 9 .... 

1904, Aug. 17.... 

1905, Aug. 15.... 

1906, Aug. I .... 

1907, July 31 .... 

1908, Sept. 2 .... 

1909, Aug. 25.... 

1910, Aug. 31 .... 

1911, Aug. 30.... 

1912, Sept. 4 .. 

1913, Sept. 10 .... 

1914, July-Sept. 

1915, Sept. 7 

1916, Sept. 5 


1919, Sept. 9 ... 

1920, Aug. 24 

1921, Sept. 7 .. 

1 922, Sept. 6 

Where held 






South Africa 











Newcastle-on Tyne... 

(No Meeting) 

(No Meeting) 




1923, Sept. 12 Liverpool 

1924, Aug. 6 Toronto. 


Sir William Turner, D.O.L., F.R.S 
Prof. A. W. Rucker, D.Sc, SeoJl.S 

Prof. J. Dewar, LL.D., F.R.S 

Sir Norman Lockyer, K.C.B., F.R.S 
Rt. Hon. A. J. Balfour, M.P., F.R.S. 
Prof. G. H. Darwin, LL.D., F.R.S. 
Prof. E. Ray Lankester, LL.D., F.R.S 

Sir David Gill, K.O.B., F.R.S 

Dr. Francis Darwin, F.R.S. 

Prof . Sir J. J. Thomson, F.R.S 

Rev. Prof. T. G. Bonney, F.R.S 

Prof. Sir W. Ramsay, K.C.B., F.R.S, 
Prof. E. A. Schafer. F.R.S. 
Sir Oliver J. Lodge, F.R.S. 
Prof. W. Batesou, F.R.S. 
Prof. A. Schuster, F.R.S. 

Sir Arthur Evans, F.R.S. 

Hon. Sir 0. Parsons, K.C.B.,F.R S.. 

Old Life i New Life 
Members ! Members 

Prof. W. A. Herdman, C.B.E., F.R.S. 

?ir T. B. Thorpe, C.B., F.K.S ! 

Sir C. S. Sherrington, G.B.E.,! 
Pres. R.S i 

Sir Ernest Rutherford, F.R.S. ... 
Sir David Bruce, K.C.B., F R.S. 













Annual Meetings — (continued). 






■ 1 


for 1 


Sums paid 

on account 

of Grants 





:or Scientific 

61072 10 





482 1 










920 9 11 






6 ; 












845 13 2 









887 18 11 









928 2 2 









882 9 









757 12 10 









1157 18 8 









1014 9 9 









963 17 


















845 7 6 









978 17 1 









1861 IS 4" 









1669 2 8 









985 18 10 



677 17 2 



326 13 3 











Annual Members 


















1272 10 

1261 13 0' 









2699 15 

618 1 10 










1699 5 

772 7 


1 123 







2735 15 

777 18 6' 


1 37 








3165 19'»1197 5 9 




' Including 848 Members of the South African Association. 

' Including 137 Members of the American Association. 

' Special arrangements were made for Members and Associates joining locally iu Australia, see 
Report, 1914, p. 686. The numbers inclade 80 Members who joined in order to attend the Meeting of 
L'Association Franijaise at Le Havre. 

• Including Students' Tickets, 10,<. 

• Including Exhibitioners granted tickets without charge. 

• Including grants from the Caird Fund in this and subsequent years. 
' Including Foreign Siiests. Exhibitioners, and others. 

■ The Bournemouth Fund for Kesearch, initiated by Sir 0. Parsons, enabed grants on account of 
scientific purposes to be maintiiiued. 

° Including grants from the Caird Gift for r search in radioactivity in this and subsequent years. 
'" Subscriptions paid iu Canada were |5 for Meeting only and others pio rata ; there was some 
pain on excliange. 



I. Professor Horace Lamb, F.R.S., has been unanimously nominated 
by the Council to fill the office of President of the Association for the year 
1925-26 (Southampton Meeting). 

II. The Council have passed resolutions of regret at the death of 
Prof. T. G. Bonney, F.R.S. (Secretary, 1881-85 ; President, 1910), Sir 
Edmund Walker, Chancellor of the University of Toronto and Vice-Presi- 
dent elect of the Association for the Toronto Meeting, and Sir William 
Herdman, C.B.E., F.R.S. (General Secretary, 1903-19 ; President, 1920). 

III. The General Officers, a Committee of the Council, and the Council 
themselves, have been fully occupied with arrangements for the Toronto 
Meeting. They acknowledge gratefully the unsparing labours of the 
executive in Toronto, with which the Secretary of the Association was 
enabled to acquaint himself during a visit, on the invitation of the 
executive, to Toronto in January. They have also to acknowledge the 
generosity of the American Association for the Advancement of Science in 
undertaking to distribute circulars relating to the Meeting to all its 

IV. Representatives of the Association have been appointed as follows : 

Physical Society of France, Fiftieth 

Anniversary ..... Professor F. Lindemann. 

Royal Colonial Institute, Committee dealing 

with conference on questions of imperial 

education at the British Empire Exhibition Professor T. P. Nunn. 
American Association for the Advancement 

of Science, Cincinnati Meeting . . Professor J. P. MacMurrich. 

Kelvin Centenary, Committee of Honour . Sir Ernest Rutherford. 
British Academy, Committee on reparation 

of losses to Imperial University Library, 

Tokyo, through earthquakef . . Professor J. L. Myres. 

Joseph Leidy Commemorative Meeting, 

Philadelphia ...... Professor W. H. Welch. 

International Mathematical Congress, 

Toronto ...... Sir William Ashley, Sir William 

Bragg, Professor G. W. 0. 

Howe, Major P. A. MacMahon. 

Franklin Institute, Centenary Celebration Sir Ernest Rutherford and Hon. 

Sir Charles Parsons. 
Association Fran9aise pour I'Avancement 

des Sciences, Liege Meeting . . . Dr. J. G. Garson. 

Sir R. A. Gregory, who was appointed to represent the Association on 
the Cinematograph Committee of the Board of Education, reports that 
the Committee has been informed of the importance attached to its work 
by the President of the Board, who is publishing its results as jDart of the 
Imperial Education Conference. 

t A set of the Association Reports, so far as available, has been presented to the 


V. Resolutions referred by the General Committee at the Liverpool 
Meeting to the Council for consideration, and, if desirable, for action, were 
dealt with as follows : — 

(a) Following upon resolutions received from all Sections excepting 
Section F, and from the Conference of Delegates of Corresponding Societies, 
regarding the provision of more adequate accommodation for the Science 
Museum, South Kensington, the Council addressed the following on the 
subject: The First Lord of the Treasury, the Lord President of the Council, 
the First Lord of the Admiralty, the Secretary of State for War, the 
Minister for Air, the President of the Board of Education, the First Com- 
missioner of Works, the Minister of Health, the President of the Board of 
Trade, the Secretary for Mines, the Parliamentary Secretary to the Office 
of Works and Transport (Board of Trade), the Postmaster-General, the 
Minister of Agriculture and Fisheries. 

(b) Following upon resolutions from several Sections and the Conference 
of Delegates, dealing with the need for more adequate protection of sites 
of scientific and historical interest, the Council addressed the appropriate 
Government Departments, and summoned a conference at which H.M. 
Office of Works and the following societies and institutions were repre- 
sented : The Royal Anthropological Institute, the Congress of Archaeo- 
logical Societies, the Architectural Association, the Folklore Society, the 
Royal Geographical Society, the Geological Society, the Geologists' 
Association, the Linnean Society, the National Trust, the British Ornitho- 
logists' Union, the Society for the Protection of Ancient Buildings, the 
Society for the Promotion of Roman Studies, and the Zoological Society. 
The chair was taken by the Rt. Hon. the Earl of Crawford and Balcarres. 
No resolution was formulated, but the discussion in general revealed 
cordial agreement with the suggestion contained in the letter summoning 
the conference, that the sole effective remedy appears to be that learned 
societies not immediately concerned in a particular problem of con- 
servation should take concerted steps to promote legislation wider in scope 
and more strictly worded than the Ancient Monuments Act now in force 
for the protection of such sites. 

(c) Following upon resolutions from several Sections and the Con- 
ference of Delegates, a letter dealing with the suspension of the sale of 
quarter-sheets of the 6-in. Ordnance Map was addressed to the Director- 
General of the Ordnance Survey, who courteously informed the Council 
of the reasons which had rendered this step necessary. 

(d) The Council gave effect to resolutions dealing with the publication 
of the reports of Committees on Geographical Teaching and on Complex 
Stress Distribution in Engineering Materials ; and approved proposals as to 
the destination of ' finds ' from the excavations at Avebury. 

(e) The Council approved the following resolutions from the 
ConfercQce of Delegates of Corresponding Societies : — 

To recommend that the publications of scientific societies should conform so far 
as possible to a standard size of page for convenience in dealing with off-prints ; and 
that for octavo publications the size of the British Association's Report be adopted as 
the standard. 


To urge the adoption by scientific societies of the bibliographical recommendations 
contained in the current Report of the Zoological Publications Committee. 

To call the attention of local scientific societies to the need for prompt and 
systematic supervision, in the interests of scientific record, of all sections and other 
excavations which are opened during the construction of new roads or other 
public works. 

A resolution dealing with the metric gallon was referred to the 
Organising Committees of Sections A and G, with a view to further 
discussion at the Annual Meeting. 

(/) A resolution received from the Committee on Marine Biological 
Research in India through the Organising Committee of Section D, dealing 
with further provision for such research in Indian waters and the establish- 
ment of a station in the Andaman Islands, was submitted to H.M. 
Secretary of State for India, with a request for his sympatheticconsideratiou, 
and has been forwarded by him to the Government of India. 

VI. The Council have received reports from the General Treasurer 
throughout the year. His accounts have been audited and are presented 
to the General Committee. 

The Council made the following grants to research committees from the 
Caird Fund :— 

Seismology Committee ... ... ... ... £100 

Naples Table Committee ... ... ... ... 100 

Bronze Implements Committee ... ... ... 60 

Tables of Constants Committee ... ... ... 15 

Zoological Record Committee ... ... ... 50 

Plymouth Marine Laboratory Committee... ... 25 

The third grant of £250 from the Caird Gift for research in radio- 
activity (for the year ending March 24, 1925) has been divided between 
Messrs. C. T. R. Wilson, A. S. Russell, and J. Chadwick. 

The British Association Exhibitions established in connection with 
the Liverpool Meeting were awarded to nineteen students nominated by 
the same number of universities and colleges, while six of these institutions 
made equivalent allowances for thirteen additional students. All were 
entertained by the Local Executive Committee at Liverpool. The fact 
that the forthcoming meeting will be overseas obviously prohibits the full 
maintenance of the scheme for the present year, but the Council are glad 
to report that certain institutions are assisting students or members of 
junior staffs to attend, and it has been found possible to offer some 
assistance from Association funds, while the local executive at Toronto 
has generously promised hospitality. 

At the meeting of the Council in December last the General Treasurer 
made the following statement : — 

It will be within the recollection of the Council that Sir Charles Parsons, when 
President at the Bournemouth Meeting in 1919, initiated a fund to enable the Associa- 
tion to maintain its grants for research. A measure of support for research had been 
given during the two years 1917-18, in spite of the fact that there were no meetings of 
the Association, in consequence of which its resources were seriously depleted. The fund 
was initiated to cover the deficit for those years as well as to assist the Association for 
the future. Ordinary working expenses were at the time exceeding receipts, especially 
in the direction of printing, despite the strict economies put into force by the Council. 

About the same time as the Bournemouth fund was initiated, the Department of 
Scientific and Industrial Research made a grant of £600 to the Association, specifying 
certain researches (within the scope of the Department) to which this sum might be 


specifically devoted, and requiring an annual statement of the expenditure. This 
account has recently been closed, and the moment is therefore opportune to summarise 
the whole position in relation to these generous gifts to the Association. The sum 
expended by the Association on research in the period 1917-2.3, excluding grants made 
at the recent meeting in Liverpool, has been £4,306. The sum received on account of 
the Bournemouth fund was £2,038, and this, together with the grant from the Research 
Department and the gifts of the late Sir James Caird, has enabled the Association still 
to meet the demands of research, while continuing to discharge its ordinary liabilities 
(greatly as these have increased since the war) and even in some measure extending 
them, as notably in the case of the ' exhibitions ' awarded in recent years to selected 
science students toward their expenses in attending annual meetings. 

It is only right to conclude this statement with reiterated thanks to the donors 
of the Bournemouth fund who so generously helped the Association over a critical 
period ; in particular the principal contributors. Sir Charles Parsons (£1,000), Sir 
Alfred Yarrow (£500), Sir R. Hadfield (£250), Sir Hugh Bell (£100), Sir William 
Herdman (£100). Such generosity encourages those responsible for the financial 
affairs of the Association to aim at establishing for it a fuller measure of financial 
independence in relation to its ordinary expenditure, and especially that incurred 
at the annual meetings, and ensuring that a fuller proportion of the sums received 
by way of membership subscription may be available for the direct support of scientific 

VII. The Council have to thank the Museums Association for its 
invitation to hold the Conference of Delegates of Corresponding Societies 
at Wembley in connexion with the Association's meeting there in July. 
Professor J. L. Myres has been nominated as President of the Conference. 

The Corresponding Societies Committee has been nominated as follows : 
The President of the Association {Chairman ex-officio), Mr. T. Sheppard 
(V ice-Chairman), the General Treasurer, the General Secretaries. Dr. 
F. A. Bather, Mr. 0. G. S. Crawford, Prof. P. F. Kendall, Mr. Mark L. 
Sykes, Dr. C. Tierney, Prof. W. W. Watts, Mr. W. Whitaker. 

VIII. The retiring Ordinary Members of the Council are : Sir R. A. 
Gregory, Mr. J. H. Jeans, Sir A. Keith, Mr. W. Whitaker, and Dr. W. E. 

The Council have received with sincere regret the resignation of 
Dr. W E. Hoyle owing to ill-health. 

The Council nominate the following new members : — 

Principal Ernest Barker | Prof. E. G. Coker 

Sir T. H. Holland 

leaving two vacancies to be filled by the General Committee without 
nomination by the Council. 

The full list of nominations of Ordinary Members is as follows : — 

Dr. P. W. Aston. 
Mr. J. Barcroft. 
Principal E. Barker. 
Sir W. H. Beveridge. 
Rt. Hon. Lord Bledisloe. 
Prof. E. G. Coker. 
Prof. W. Dalby. 
Prof. C. H. Desch. 
Mr. E. N. Fallaize. 
Dr. J. S. Flett. 
Prof. H. J. Fleure. 

Prof. A. Fowler. 
Sir Daniel Hall. 
Mr. C. T. Heycock. 
Sir T. H. Holland. 
Sir J. Scott Keltic. 
Prof. A. W. Kirkaldy. 
Dr. P. Chalmers Mitchell. 
Dr. C. S. Myers. 
Prof. A. W. Porter. 
Prof. A. C. Seward. 
Prof. A. Smithells. 
Mr. A. G. Tansley. 


IX. The General Officers have been nominated by the Council as 
follows : — 

General Treasurer : Dr. E. H. Griffiths. 

General Secretaries : Prof. J. L. Myres, Mr. F. E. Smith. 

X. The following have been admitted as members of the General 
Committee : — 

Prof. E. H. NeviUe. 

Mr. L. L. Belinfante. 
Mr. D. Ward Cutler. 

Mr. H. J. Page. 

Dr. G. H. Vevers. 

XI. The Council have put into operation for the Toronto Meeting 
the following alteration of practice in regard to eligibility for Students' 
Tickets, and recommend the same as a change in the Rules : — 

To substitute for Sections (iii) (iv) of Rule X, 2 : — 

(iii) Persons not exceeding 23 years of age, being students of universities or of any 
educational institution recognised by the Local Executive Committee or the General 
Officers of the Association, may obtain ' students' tickets ' for the meeting on payment 
of 10s. Holders of such tickets shall not be entitled to any privilege beyond attendance 
at the Annual Meeting. 


Owing to distance and expense, it was not possible to assist the usual 
number of selected science students to attend the Meeting from Britain. 
Five students, however, were enabled to do this by the co-operation of 
King's College, London, University College, Cardifi, University College, 
Exeter, and the Local Committee in Toronto, and with assistance from 
the funds of the Association. 


Inaugural General Meeting. 

The Inaugural General Meeting took place in Convocation Hall, Univer- 
sity of Toronto, on Wednesday, August 6, at 8.30 p.m. 

Sir Ernest Rutherford, F.R.S., read the following letter from H.R.H. 
The Prince of Wales, K.G., F.R.S. :— 

St. James's Palace, S.W.I. 
Jidy 3, 1924. 

Dear Mr. President, — Will you be good enough to convey to the members of the 
British Association at their inaugural meeting in Toronto my cordial good wishes for 
a very successful session ? 

My knowledge of Canada assures me that your visit will be warmly welcomed, and 
that nothing but good can come of such a gathering, where the representatives of the 
most advanced thought from the old country will meet in discussion the equally keen 
and active intellects of the younger land. 


My interest has been particularly arrested by one item that is to come up for dis- 
cussion, namely, the educational training of boys and girls in this country for life over- 
seas. The call of the Empire for a wider distribution of the home population, for men 
and women to open up the vast uncultivated areas in the great overseas dominions, is 
more imperative to-day than at any time in its history. 

I congratulate the Association on thus showing in its deliberations such a broad 
interest in these problems, and I trust, and indeed am confident, that the influence 
thus exercised may result in great and extended benefits to the Empire. — Yours 


The President of the British Association. 

To this gracious message the following reply was telegraphed from the 

meeting : — 

H.R.H. The Prince of Wales, St. James's Palace, London. 

British Association for Advancement of Science at inaugural meeting, Toronto, 
August 6, begs leave humbly to thank Your Royal Highness for gracious message, 
which enhances our hope and belief that substantial benefits to cause of science will 
accrue from this meeting of scientific workers from Britain, Canada and America. 
Your Royal Highness's personal interest in educational training of boys and girls for 
life overseas is especially appreciated. 

Ernest Rtttheeford, President. 

The Association was welcomed to Toronto by Sir Robert Falconer, 
K.C.M.G., President of the University of Toronto, on behalf of the Univer- 
sity ; by Prof. J. C. Fields, F.R.S., President of the Royal Canadian Institute, 
on behalf of that body ; and by the Hon. Forbes Godfrey, Minister of 
Health, on behalf of the Government of the Province of Ontario. 

Sir Ernest Rutherford, F.R.S., resigned the office of President of the 
Association to Major-General Sir David Bruce, K.C.B., F.R.S., who 
delivered an address on Prevention of Disease (for which see p. 1). 

Evening Discourses. 

Sir Thomas Holland, K.C.M.G., F.R.S. : ' The Formation and Destruction 

of Mineral Deposits.' 8.30 p.m., August 8, Convocation Hall. 
Professor D'Arcy Wentworth Thompson, C.B., F.R.S. : ' The Shell of the 
. Nautilus.' 8.30 p.m., August 11, Convocation Hall. 

Citizens' Lectures. 

Sir Henry Fowler, K.B.E. : ' Metallurgy and its Influence on Social Life.' 

8 p.m., Thursday, August 7, Assembly Hall, Jarvis Collegiate Institute. 
J. S. Huxley, M.A. : ' Control of Growth.' 8 p.m., Friday, August 8, 

University of Toronto Schools. 
Professor A. S. Eddington, F.R.S. : ' Einstein's Theory of Relativity.' 

8 p.m., Saturday, August 9, Convocation Hall. 
Sir R. Robertson, M.A., F.R.S. : ' Explosives ' (with experiments). 

8 p.m., Monday, August 11, Assembly Hall, Oakwood Collegiate 

Professor E. P. Cathcart, C.B.E. : ' Seeing is BeUeving.' 8 p.m., Tuesday, 

August 12, Assembly Hall, University of Toronto Schools. 



Children's Lectures. 

Sir W. Bragg, K.B.E., D.Sc, F.R.S. : ' Diamond and Black Lead.' 

4 p.m., Friday, August 8, Convocation Hall. 
Professor J. H. Priestley, D.S.O. : ' Plant Waterproofs.' 3.30 p.m., 

Monday, August 11, Lecture Hall, Physics Building, University of 

Captain L. H. Dudley Buxton : ' Beyond the Great Wall of China and the 

People who live there.' 3 p.m., Tuesday, August 12, Assembly 

Hall, Central Technical School. 

Scientific Exhibition. 

An Exhibition of scientific instruments, apparatus, and books was 
opened in the University throughout the Meeting. 

Concluding General Meeting. 

The Concluding General Meeting was held in Convocation Hall on 
Wednesday, August 13, at 5.30 p.m., when the following Resolutions were 
adopted with acclamation ; — 

1. The British Association for the Advancement of Science most warmly thanks the 
University of Toronto and the Royal Canadian Institute for the invitation which has 
led to the brilliant Meeting now concluding ; and in particular to the University for 
placing at the disposal of the Association its meeting-rooms, residences, and other 
resources. Gratitude is also due to the Governments of the Dominion and of the 
Province of Ontario, the City of Toronto, and private donors, for their generous contri- 
bution of funds toward the expenses of the Meeting. Those of the members who are 
about to take part in the Western Excursion have further to express their obligation to 
the Western Provinces which have contributed toward the cost of the excursion. The 
best thanks of the Association are due to members of the University faculty, the staff, 
and others, who have laboured unsparingly in the organisation of the Meeting; and it 
has also to acknowledge the generous hospitality of numerous institutions and indi- 
viduals. The large attendance of citizens, whose presence has so greatly contributed to 
the success of the Meetings, is deeply appreciated ; as also are the able support afforded 
by the Press and the unfailing assistance of transport companies and other authorities. 

2. The best thanks of the British Association are accorded to the American Associa- 
tion for the Advancement of Science for its cordial and effective co-operation.' 

After the above Resolutions had been proposed and answered, the 
President brought the Meeting to a conclusion with an expression of thanks 
to Canada. 

' The American Association distributed some 17,000 of the British Association's 
circulars to its members and those of societies in correspondence with it, and took 
every possible measure to ensure a large and representative attendance of American 
men of science at the Toronto Meeting. It was resolved that Members of the 
American Association taking the $5 ticket for the Meeting should receive the Report, 
if desired, without further charge. 




July 1, 1923, to June 30, 1924. 

(Note. — An increase which will be observed in the cost of printing is accounted 
for by the facts that the Report for 1923 was larger, and the number required 
larger, than in 1922. Preparations for a meeting overseas in 1924 further 
necessitated increased printing of programmes, and larger expenditure on postage 
and stationery.) 



Balance Sheet, 


To Capital Accounts — 

General Fund, as per contra ..... 
(Subject to Depreciation in Value of Investments) 

„ Caird Fund — 

As per contra ....... 

(Subject to Depreciation in Value of Investments) 

,, Caird Fund — 

Revenue Account, Balance as at July 1, 1923 

Add Excess of Income over Expenditure for the year 

„ Caird Gift, Radio -Activity Investigation — ■ 

Balance at July 1, 1923 ...... 

Add Dividends on Treasury Bonds 

Income Tax Recovered .... 

Profit on Sale of Treasury Bonds 

Less Grants Paid ...... 

„ Sir F. Bramwell's Gift for Enquiry into Prime Movers, 1931- 
£50 Consols accumulated to June 30, 1924, as per contra 

,, Sir Charles Parson's Gilt ...... 

„ John Perry Guest Fund — 

For cases of emergency 

„ Life Compositions as at July 1, 1923 
Add Received duriag year 

„ Legacy, T. W. Backhouse . 

„ Sundry Creditors 

„ Income and Expenditure Account — - 
Balance at July 1, 1923 

Add Excess of Income over Expenditure for the year 

£ s. 


£ s. 


10,575 15 


9,582 16 


687 2 
44 7 


731 9 


857 19 
20 16 
10 15 
42 18 



932 9 4 

connected with Guests of the 


81 16 

. 2,958 19 
855 12 


582 9 4 

59 10 



3,896 7 2 

£36,463 7 3 

I have examined the foregoing Account with the Books and Vouchers and certify the same 


ARTHUR L. BOWLEY | ^„^,7„., 
A. W. KIRKALDY I Auaitors. 

July 11, 1924. 



June 30, 1924. 


By Investments on Capital Accounts — General Fund — 

£4,651 10s. 5d. Consolidated 2i per cent. Stocli at cost 

£3,600 India 3 per cent. Stock at cost 

£879 14s. 9d. £43 Great Indian Peninsula Railway " B 

Annuity at cost ....... 

£52 12s. Id. War Stock (Post Office Issue) at cost 

£810 10s. 3d. War Stock converted to £834 16s. 6d. 4* per 

cent. Conversion Loan at cost .... 
£1,400 War Loan Bonds 5 per cent, at cost 

Value at date, £6,321 10s. lOd. 

„ Caird Fund — ^, , ^ 

£2,627 Os. lOd. India 3i per cent. Stock at cost 
£2,100 London Midland and Scottish Railway Consolidated 
4 per cent. Preference Stock at cost .... 
£2,500 Canada 3^ per cent. 1930/50 Registered Stock at cost 

£2,000 Southern Railway Consolidated 5 per cent. Preference 
Stock at cost ........ 

Value at date, £7,502 19s. Id. 

„ Caird Fund Revenue Account — 

Cash at Bank ........ 

„ Caird Gift— 

£400 Registered Treasury Bonds ..... 
Cash at Bank ........ 

,, Sir F. Bramwell's Gift — 

£116 8 6 2J per cent. Self-Accumulating Consolidated 
' Stock as per last Balance Sheet . 
5 2 Add Accumulations to June 30, 1924 

s. d. 











2,400 13 3 


£121 10 6 

Value at date, £69 5s. id. 

Sir Charles Parson's Gift — 

£10,000 5 per cent. War Loan converted to £10,300 4^ per 
cent. Conversion Stock at cost ..... 
Value at date, £10,068 5s. Od. 

John Perry Guest Fund — 

£96 National Savings Certificates at cost .... 
Cash at Bank ........ 

Life Compositions — 

£649 38. id. Local Loans at cost ..... 
Cash at Bank ........ 

Legacy — T. W. Backhouse — 

Cash at Bank ........ 

Revenue Account — 

£2,098 Is. 9d. Consolidated 2i per cent. Stock at cost. 

£1,500 Registered Treasury Bonds at cost 

Sundry Debtors ........ 

Cash at Bank 1,408 11 

Cash on Deposit 1,000 

Cash in Hand ..... 917 

Less as shown above — 

Caird Fund Revenue Account 731 

Caird Gift 

John Perry Guest Fund 

Life Compositions. 

Legacy — T. W. Backhouse 











2,417 2 6 

1.454 10 8 

2,594 17 3 

182 9 


56 11 
2 19 






233 15 

£ s. d. 

10,575 15 2 

9,582 16 3 

731 9 4 

582 9 4 

59 10 





962 11 10 

3,896 7 2 
£36,463 7 3 

to be correct. I have also verified the Balances at the Bankers and the Investments. 

W. B. KEEN, 

Chartered Accountant. 



Income and 



li 12 
47 4 



S. d. 


201 16 10 







257 18 6 

336 19 9 

3,889 12 6 

To Heat and Lighting 
„ Stationery 
„ Rent 
,, Postages 

,, Travelling Expenses 
,, Exhibitioners 
„ General Expenses . 

Salaries and Wages .... 

Pension Contribution .... 
Printing, Binding, etc. .... 

Sir Robert Hadfield's Gift — 

Grants to Universities 
Grants to Research Committees — 

Index Kewensis Committee 

Old Red Sandstone of the Bristol District 
Committee .... 

Corresponding Societies Committee 

Growth of Children Committee 

Parthenogenesis Committee 

Colloid Chemistry Committee 

Sti'ess Distributions Committee 

Overseas Training Committee . 

Pre -Cambrian Rocks Committee 

Marine Algae Committee . 

Muscular Stiffness Committee . 

Auxiliary Language Committee 

Characteristic Fossils Committee 

Lower Carboniferous Committee 

Quaternary Peats Committee 

Cost of Cycling Committee 

Botanical Survey of Sherwood Forest 
Committee .... 

Population Map Committee 

Glacial Deposits Committee 

Derbyshire Caves Committee 

Tertiary Rocks Committee 

Old Red Sandstone Rocks of Kiltorcan, 
Ireland, Committee 

Zoological Bibliography Committee 

Bronze Age Implements Committee 

Balance, being Excess of Income over Expend: 
ture for the year .... 

£ s. d. 

14 7 8 

68 10 10 


225 7 7 

113 14 

27 14 10 

177 9 

s. d. 











3,684 12 5 





























497 5 
855 12 




£5,087 10 4 

£ s. d. 


113 10 4 

£383 10 4 


To Grants Paid — 

Tables of Constants Committee 
Plymouth Station Committee . 
Naples Station Committee 
Bronze Age Implements Committee 
Zoological Record Committee 
Seismological Investigations Committee 

„ Balance, being Excess of Income over Expendi- 
ture for the year . . . . . 

£ s. d. 








s. d. 



£394 7 


Expenditure Account 

Ended June 30, 1924. 














By Annual Members (Including £87 10s. Od., 1924/25) 
,, Annual Members, Temporary (Including 




£327, 1921/25) 

„ Annual Members, with Report (Including 



£133 10s., 1924/25) 





„ Transferable Tickets (Including £2 10s., 1924/25) 





„ Students' Tickets (Including £3 10s., 1924/25) . 
,, Life Members' additional Subscriptions 




,, Donations ....... 







,, Interest on Deposits ..... 







„ Advertisements ...... 






„ Sales of Publications ..... 





„ Sir Robert Hadfleld's Gift .... 





,, Unexpended Balance of Grants returned . 







„ Income Tax Recovered ..... 




,, Dividen 


116 14 4 

Consols ...... 





India 3 per cent. .... 


24 19 4 

Great Indian Peninsula " B " Annuity 




96 10 6 

War Stock 




War Stock, Sir Charles Parson's Gift . 


59 1 3 

Treasury Bonds .... 




1 16 6 

Local Loans ..... 










3,889 12 6 

£5,087 10 4 


s. d. 

270 5 6 
113 4 10 

£383 10 


By Dividends on Investments — 

India 3i per cent. .... 

Canada 34 per cent. 

London Midland aud Scottish Railway Con 
solidated 4 per cent. Preference Stock 

Southern Railway Consolidated 5 per cent- 
Preference Stock .... 

„ Income Tax Recovered .... 

£ s. d. 

91 18 
67 16 


64 11 


7G 17 











Grants of money, if any, from the Association for expenses connected 
with researches are indicated in heavy type. 


Seismological Investigations. — Prof. H. H. Turner (Chairman), Mr. J. J. Shaw 
(Secretary), Mr. C. Vernon Boys, Dr. J. E. Crombie, Dr. C. Davison, 
Sir F. W. Dyson, Sir R. T. Glazebrook, Prof. H. Lamb, Sir J. Larmor, Prof. 
A. E. H. Love, Prof. H. M. Macdonald, Prof. H. C. Plummer, Mr. W. E. 
Plummer, Prof. R. A. Sampson, Sir A. Schuster, Sir Napier Shaw, Dr. G. T. 
Walker. £100 (Caird Fund grant). 

Tides. — Prof. H. Lamb (Chairman), Dr. A. T. Doodson (Secretary), Dr. G. R. 
Goldsbrough, Dr. H. Jeffreys, Prof. J. Proudman, Prof. G. I. Taylor, Prof. 
D'Arcy W. Thompson, Commander H. D. Warburg. 

Annual Tables of Constants and Numerical Data, chemical, physical, and technological. 
— Sir E. Rutherford (Chairman), Prof. A. W. Porter (Secretary), Mr. Alfred 
Egerton. £5 (Caird Fund grant, to be applied for from Council). 

Calculation of Mathematical Tables. — Prof. J. W. Nicholson (Chairman), Dr. J. R. 
Airey (Secretary), Mr. T. W. Chaundy, Prof. L. N. G. Filon, Prof. E. W. Hobson, 
Mr. G. Kennedy, and Profs. Alfred Lodge, A. E. H. Love, H. M. Macdonald, 
G. B. Mathews. £35 (for printing). 

Investigation of the Upper Atmosphere. — Sir Napier Shaw (Chairman), Mr. C. J. P. 
Ca,Ye> .(Secretary), Prof. S. Chapman, Mr. J. S. Dines, Mr. L. H. G. Dines, Mr. 
W. H. Dines, Sir R. T. Glazebrook, Col. E. Gold, Dr. H. Jeffreys, Sir J. Larmor, 
Mr. R. G. K. Lempfert, Prof. F. A. Lindemann, Dr. W. Makower, Mr. J. Patterson, 
Sir J. E. Petavel, Sir A. Schuster, Dr. G. C. Simpson, Mr. F. J. W. Whipple, Prof. 
H. H. Turner. 

To investigate local variations of the Earth's Gravitational Field. — Col. H. G. Lyons 
(Chairman), Capt. H. Shaw (Secretary), Mr. C. Vernon Boys, Dr. C. Chree, Col. 
Sir G. P. Lenox-Conyngham, Dr. J. W. Evans, Mr. E. Lancaster-Jones, the 
Director-General, Ordnance Survey ; the Director, Geological Survey of Great 
Britain. £50. 


Colloid Chemistry and its Industrial Applications. — Prof. F. G. Donnan (Chairman), 
Dr. W. Clayton (Secretary), Mr. E. Hatschek, Prof. W. C. McC. Lewis, Prof. J. W. 
McBain. £5. 

Absorption Spectra and Chemical Constitution of Organic Compounds. ^ — Prof. I. M. 
Heilbron (Chairman), Prof. E. C. C. Baly (Secretary), Prof. A. W. Stewart. £10. 

The Position of the Quantum Theory in its relations to Chemistry. — Prof. W. C. 
McC. Lewis (Chairman), Dr. J. RicR (Secretary), Prof. E. C. C. Baly, Prof. F. G. 
Donnan, Prof. A. Fowler, Dr. E. K. Rideal. £10. 

The Chemistry of Vitamins. — Prof. F. G. Hopkins (Chairman), Prof. J. C. Drummond 
(Secretary), Prof. G. Barger, Prof. A. Harden, Principal J. C. Irvine, Prof. J. W. 
McBain, Prof. Lash Miller, Dr. S. Zilva. 



The Old Red Sandstone Rocks of Kiltorcan, Ireland. — Mr. W. B. Wright {Chairman), 
Prof. T. Johnson (Secretary), Dr. W. A. Bell, Dr. J. W. Evans, Prof. W. H. 
Lang, Sir A. Smith Woodward. £15. 

To excavate Critical Sections in the Palaeozoic Rocks of England and Wales. — Prof. 
W. W. Watts {Chairman), Prof. W. G. Feamsides {Secretary), Prof. W. S. Boulton, 
Mr. E. S. Cobbold, Dr. Gertrude Elles, Prof. E. J. Garwood, Mr. V. C. Illing, Prof. 
0. T. Jones, Dr. J. E. Marr, Dr. W. K. Spencer. £20 (including £5 travelling 

The Collection, Preservation, and Systematic Registration of Photographs of Geo- 
logical Interest. — Prof. E. J. Garwood {Chairman), Prof. S. H. Reynolds {Secretary), 
Mr. G. Bingley, Messrs. C. V. Crook and A. S. Reid, Prof. W. W. Watts, and Messrs. 
R. Welch and W. Whitaker. 

To investigate the Flora of Lower Carboniferous times as exemplified at a newly 
discovered locality at GuUane, Haddingtonshire. — Prof. W. W. Watts (Chairman), 
Prof. W. T. Gordon (Secretary), Dr. J. S. Flett, Prof. E. J. Garwood, Dr. J. Home, 
and Dr. B. N. Peach. 

To investigate the Stratigraphical Sequence and Palseontology of the Old Red Sand- 
stone of the Bristol district. — Dr. H. Bolton (Chairman), Mr. F. S. Wallia 
(Secretary), Miss Edith Bolton, Prof. A. H. Cox, Mr. D. E. I. Innes, Prof. C. Lloyd 
Morgan, Prof. S. H. Reynolds, Mr. H. W. Turner. £20. 

To investigate the Quaternary Peats of the British Isles. — Prof. P. F. Kendall (Chair, 
man), Mr. L. H. Tonks (Secretary), Prof. P. G. H. Boswell, Miss Chandler, Prof. 
H. J. Fleure, Dr. E. Greenly, Prof. J. W. Gregory, Prof. G. Hickling, Mr. J. de W. 
Hinch, Mr. R. Lloyd Praeger, Mrs. Reid, Mr. T. Sheppard, Mr. J. W. Stather, 
Mr. A. W. Stelfox, Mr. C. B. Travis, Mr. A. E. Trupman, Mr. W. B. Wright. £60. 

Comparison of the Rocks of Pre-Cambrian and presumably Pre-Cambrian Inliers of 
England and Wales and the Dublin Area with the Rocks of the Mona Complex 
of Anglesey, with a view to possible correlation. — Dr. Gertrude Elles (Chairman), 
Dr. Edward Greenly (Secretary), Mr. T. C. Nicholas, Prof. S. H. Reynolds, 
Dr. C. E. Tilley. 

To investigate Critical Sections in the Tertiary Rocks of the London Area. To tabulate 
and preserve records of new excavations in that area. — Prof. W. T. Gordon (Chair- 
man), Dr. S. W. Wooldridge (Secretary), Miss M. C. Crosfield, Prof. H. L. Hawkins, 
Prof. G. Hickling, Mr. W. Whitaker. £15 (including £5 travelling fares). 

To attempt to obtain agreement regarding the significance to be attached to Zonal 
Terms used in connection with the Lower Carboniferous. — Prof. P. F. Kendall 
(Chairman), Mr. R. G. Hudson (Secretary), Mr. J. W. Jackson, Mr. W. B. Wright. 


To aid competent Investigators selected by the Committee to carry on definite pieces 
of work at the Zoological Station at Naples. — Prof. E. S. Goodrich (Chairman), 
Prof. J. H. Ash worth (Secretary), Dr. G. P. Bidder, Prof. F. 0. Bower, Dr. W. B. 
Hardy, Sir S. F. Harmer, Prof. S. J. Hickson, Sir E. Ray Lankester. £100 
from Caird Fund, subject to approval of Council. 

Zoological Bibliography and Publication.— Prof. E. B. Poulton (Chairman), Dr. F. A. 
Bather (Secretary), Mr. E. Heron-Allen, Dr. W. T. Caiman, Dr. P. Chalmers 
Mitchell, Mr. W. L. Sclater. £1. 

Parthenogenesis. — Prof. A. Meek (Chairman), Mr. A. D. Peacock (Secretary), Mr 
R. S. Bagnall, Dr. J. W. Heslop-Harrison. £5. 

To nominate competent Naturalists to perform definite pieces of work at the Marine 
Laboratory, Plymouth. — Prof. A. Dendy (Chairman and Secretary), Prof. J. H. 
Ashworth, Prof. W. J. Dakin, Prof. S. J. Hickson, Sir E. Ray Lankester. £25 
(Caird Fund grant, to be applied for from Council). 


To co-operate with other Sections interested, and with the Zoological Society, for 
the purpose of obtaining support for the Zoological Record. — Sir S. Harmer 
(Chairman), Dr. W. T. Caiman (Secretary), Prof. A. Dendy, Prof. E. S. Goodrich, 
Prof. D. M. S. Watson. £50 (Caird Fund grant, to be applied for from 

Pre-natal influence of Anti-sera on the Eye-lens of Rabbits. — Prof. W. J. Dakin (Chair- 
man), Mr. J. T. Cunningham (Secretary), Prof. D. M. S. Watson. £20. 


To consider the advisability of making a provisional Population Map of the British 
Isles, and to make recommendations as to the method of construction and 
reproduction. — Mr. H. O. Beckit (Chairman), Mr. F. Debenham (Secretary), 
Mr. J. Bartholomew, Prof. H. J. Fleure, Mr. R. H. Kinvig, Mr. A. G. Ogilvie, 
Mr. O. H. T. Rishbeth, Prof. P. M. Roxby. £30. 


To formulate suggestions for a S3'llabus for the teaching of Geography both to Matricu- 
lation Standard and in Advanced Courses ; to report upon the present position 
of the geographical training of teachers, and to make recommendations thereon ; 
and to report, as occasion arises, to Council through the Organising Committee 
of Section E, upon the practical working of Regulations issued by the Board of 
Education affecting the position of Geography in Training Colleges and Secondary 
Schools.— Prof. T. P. Nunn (Chairman), Mr. W. H. Barker (Secretary), Mr. L. 
Brooks, Prof. H. J. Fleure, Mr. O. J. R. Howarth, Sir H. J. Mackinder, Prof. 
J. L. Myres, and Prof. J. F. 'Unstead( from Section E) ; Mr. Adlam, Mr. D. Berridge, 
Mr. C. E. Browne, Sir B. Gregory, Mr. E. Sharwood Smith, Mr. E. R. Thomas, Miss 
O. Wright (from Section L). £5. 


To report on certain of the more complex Stress Distributions in Engineering Materials. 
— Prof. E. G. Coker (Chairman), Prof. L. N. G. Filon and Prof. A. Robertson 
(Secretaries), Prof. T. B. Abell, Prof. A. Barr, Mr. Charles Brown, Dr. Gilbert 
Cook, Prof. W. E. Dalby, Sir J. A. Ewing, Sir H. Fowler, Mr. A. R. Fulton, 
Dr. A. A. Griffith, Mr. J. J. Guest, Dr. B. P. Haigh, Profs. Sir J. B. Henderson, 
C. E. Inglis, F. C. Lea, A. E. H. Love, and W. Mason, Sir J. E. Petavel, Dr. F. 
Rogers, Dr. W. A. Scoble, Mr. R. V. Southwell, Dr. T. E. Stanton, Mr. C. E. 
Stromeyer, Mr. G. I. Taylor, Mr. A. T. Wall. Mr. J. S. Wilson. £10. 


To report on the Distribution of Bronze Age Implements. — Prof. J. L. Myres (Chair- 
man), Mr. H. Peake (Secretary), Mr. Leslie Armstrong, Mr. H. Balfour, Prof. T. H. 
Bryce, Mr. L. H. D. Buxton, Mr. O. G. S. Crawford, Prof. H. J. Fleure, Dr. Cyril 
Fox, Mr. G. A. Garfitt, Prof. Sir W. Ridgeway. £100 (Caird Fund grant, to be 
applied for from Council). 

To conduct Archsftological Investigations in Malta. — Prof. J. L. Myres (Chairman), 
Sir A. Keith (Secretary), Dr. T. Ashby, Mr. H. Balfour. 

To conduct Explorations with the object of ascertaining the Age of Stone Circles. — 
Sir C. H. Read (Chairman), Mr. H. Balfour (Secretary), Dr. G. A. Auden, Prof. 
Sir W. Ridgeway, Dr. J. G. Garson, Sir Arthur Evans, Sir W. Boyd Dawkins, 
Prof. J. L. Myres, Mr. H. J. E. Peake. 

Tojexcavate Early Sites in Macedonia. — Prof. Sir W. Ridgeway (Chairman), Mr. 
'S. Casson (Secretary), Prof. R. C. Bosanquet, Dr. W. L. H. Duckworth, Prof. 
J. L. Myres, Mr. M. Thompson. 


To report on the Classification and Distribution of Rude Stone Monuments. — Mr. 
G. A. Garfitt {Chairman), Mr. E. N. Fallaize {Secretary), Mr. O. G. S. Crawford, 
Miss R. M. Fleming, Prof. H. J. Fleure, Dr. C. Fox, Mr. G. Marshall, Prof. J. L. 
Myres, Mr. H. J. E. Peake. £5. 

The Collection, Preservation, and Systematic Registration of Photographs of Anthro- 
pological Interest. — Mr. E. Torday {Chairman), Mr. E. N. Fallaize {Secretary), 
Dr. G. A. Auden, Dr. H. A. Auden, Mr. E. Heawood, Prof. J. L. Myres. 

To report on the probable sources of the supply of Copper used by the Sumerians. — 
Mr. H. J. E. Peake (Chairman), Mr. G. A. Garfitt {Secretary), Mr. H. Balfour, 
Mr. L. H. Dudley Buxton, Prof. C. H. Desch, Sir Flinders Petrie. 

To conduct Archajological and Ethnological Researches in Crete. — Dr. D. G. Hogarth 
{Chairinan), Prof. J. L. Myres (Secretary), Prof. R. C. Bosanquet, Dr. W. L. H. 
Duckworth, Sir A. Evans, Prof. Sir W. Ridgeway, Dr. F. C. Shrubsall. 

To report on the present state of knowledge of the relation of early Paljeolithic 
Implements to Glacial Deposits. — Mr. H. J. E. Peake (Chairman), Mr. E. N. 
Fallaize (Secretary), Mr. H. Balfour, Prof. P. G. H. Boswell, Mr. M. Burkitt, Prof. 
P. F. Kendall, Mr. G. Lamplugh, Prof. J. E. Marr. £30. 

To investigate the Lake Villages in the neighbourhood of Glastonbury in connection 
with a Committee of the Somerset Archaeological and Natural History Society. — 
Sir W. Boyd Dawkins (Chairman), Mr. Willoughby Gardner (Secretary), Mr H. 
Balfour, Mr. A. Bulleid, Mr. F. S. Palmer, Mr. H. J. E. Peake. 

To co-operate with a Committee of the Royal Anthropological Institute in the explor- 
ation of Caves in the Derbyshire district. — Sir W. Boj'd Dawkins (Chairman), 
Mr. G. A. Garfitt (Secretary), Mr. Leslie Armstrong, Mr. M. Burkitt, Mr. E. n! 
Fallaize, Dr. R. V. Favell, Mr. Wilfrid Jackson, Dr. R. R. Marett, Mr. L. S 
Palmer, Mr. H. J. E. Peake. 

To investigate processes of Growth in Children, with a view to discovering Differences 
due to Race and Sex, and further to study Racial Differences in M'omen. — Sir 
A. Keith (Chmrman), Prof. H. J. Fleure (Secretary), Mr. L. H. Dudley Buxton, 
Dr. A. Low, Prof. F. G. Parsons, Dr. F. C. Shrubsall. £20. (A proportion not 
exceeding two-thirds of this grant may be expended on railway fares incurred in 
course of the investigation.) 

To conduct Excavations and prepare a Survey of the Coldrum Megalithic Monument. — 
Sir A. Keith (Chairman), Prof. H. J. Fleure (Secretary), Mr. H. J. E. Peake 

To report on proposals for an Anthropological and Archaeological Bibliography, with 
power to co-operate with other bodies. — Dr. A. C. Haddon (Chairman), Mr. E. N. 
Fallaize (Secretary), Dr. T. Ashby, Mr. W. H. Barker, Mr. O G. S. Crawford! 
Prof. H. J. Fleure, Prof. J. L. Myres, Mr. H. J. E. Peake, Dr. D. Randall-Maclver, 
Mr. T. Sheppard. 

To report on the progress of Anthropological Teaching in the present century. — 
Dr. A. C. Haddon (Chairman), Prof. J. L. Myres (Secretary), Prof. H. J. Fleure, 
Dr. R. R. Marett, Prof. C. G. Seligman. £5. 

To investigate certain Physical Characters and the Family Histories of Triplet Children. 
—Dr. F. C. Shrubsall (Chairman), Mr. R. A. Fisher (Secretary), Miss R. M. Fleming, 
Dr. A. Low. £25. 

To report on the possibility of Physiological Tests of Races, such as the Blood Agglu- 
tination. — Dr. F. C. Shrubsall (Chairman), Mr. L. H. Dudley Buxton (Secretary), 
Dr. Davidson Black, Dr. H. H. Dale, Dr. A. C. Haddon, Prof. G. H. F. Nuttall. 

To conduct Explorations on early Neolithic Sites in Holdemess. — Mr. H. J. E. Peake 
(Chairman), Mr. A. Leslie Armstrong (Secretary), Mr. M. Burkitt, Dr. R. V. 
Favell, Mr. G. A. Garfitt, Mr. Wilfrid Jackson, Mr. L. S. Palmer. 

To conduct Anthropometric Investigations among the Indians of the Canadian Rockies. — 
Dr. A. C. Haddon (Chairman), Mr. H. Balfour (Secretary), Dr. E. Sapir. £100. 



Muscular Stiffness in relation to Respiration. — Prof. A. V. Hill {Chairman), Dr. Ff. 
Roberts (Secretary), Mr. J. Barcroft. 

The Cost of Cycling with varied rate and work. — Prof. J. S. Macdonald (Chairman), 
Dr. F. A. Duffield (Secretary). £30. 

The Investigation of the Medullary Centres. — Prof. C. Lovatt Evans (Chairman), 
Mr. J. M. Duncan Scott (Secretary), Dr. H. H. Dale. £20. 


The Place of Psychology in the Medical Curriculum. — Prof. G. Robertson {Chairman), 
Dr. J. Drever (Secretary), Dr. W. Brown, Dr. R. G. Gordon, Dr. C. S. Myers, Prof. 
T. H. Pear, Dr. F. C. ShrubsaU. 

Vocational Tests. — Dr. C. S. Myers (Chairman), Dr. G. H. Miles (Secretary), Mr. C. 
Burt, Prof. T. H. Pear, Mr. F. Watts, Dr. LI. Wynn-Jones. 

The Character of a first-year University Course in Experimental Psychology. — Dr. J. 
Drever (Chairman), Dr. May Collins (Secretary), Mr. F. C. Bartlett, Mr. R. J. 
Bartlett, Prof, E. A. Bott, Dr. C. Burt, Dr. Shepherd Dawson, Mr. A. E. Heath, 
Dr. LI. Wynn-Jones, Prof. T. H. Pear. 

The uniformity of Terminology and Standards in the Diagnosis of Mental Deficiency. — 
Dr. C. Burt (Chairman), Miss Evelyn Fox (Secretary), Miss L. G. Fildes, Dr. 
Kennedy Fraser, Dr. F. C. ShrubsaU. 


The Physiology and Life-history of Marine Algse at Port Erin.— Prof. J. McLean 
Thompson (Chairman), Dr. M. Knight (Secretary), Prof. F. E. Weiss. £25. 

Index Kewensis. — Sir D. Prain (Chairman), Dr. A. W. Hill (Secretary), Prof. J. B. 
Farmer, Dr. A. B. Rendle, Prof. W. Wright Smith. £100- 

Botanical Survey of Sherwood Forest. — Prof. R. H. Yapp (Chairman), Dr. H. S. Holden 
(Secretary), Mr. A. G. Tansley. (With power to apply unexpended balance of 
last year's grant.) 


To inquire into the Practicability of an International Auxiliary Language. — Dr. H. 
Forster Morley (Chairman), Dr. E. H. Tripp (Secretary), Mr. E. BuUough, Prof. 
J. J. Findlay, Sir Richard Gregory, Mr. W. B. Hardy, Dr. C. W. Kimmins, 
Sir E. Cooper Perry, Mr. Nowell Smith, Mr. A. E. Twentyman. £3. 

To consider the educational training of boys and girls in Secondary Schools for over- 
seas life.— Rev. H. B. Gray (Chairman), Mr. :C. E. Browne (Secretary), Dr. J. 
Vargas Eyre, Sir R. A. Gregory, Sir J. Russell. £20. 


Corresponding Societies Committee. — The President of the Association (Chairman 
ex-officio), Mr. T. Sheppard ( Vice-Chairman), the General Secretaries, the General 
Treasurer, Dr. F. A. Bather, Mr. 0. G. S. Crawford, Prof. P. F. Kendall, Mr. 
Mark L. Sykes, Dr. C. Tiemey, Prof. W. W. Watts, Mr. W. Whitaker ; with 
authority to co-opt representatives of Scientific Societies in the locality of the 
Annual Meeting. £40 for preparation of bibliography and report. 



An unconditional gift of £10,000 for research was made to the 
Association at the Dundee Meeting, 1912, by Mr. (afterwards Sir) 
J. K. Caird, LL.D., of Dundee. 

The Council, in its report to the General Committee at the Birming- 
ham Meeting, made certain recommendations as to the administration 
of this Fund. These recommendations were adopted, with the Eeport, 
by the General Committee at its meeting on September 10, 1918. 

The allocations made from the Fund by the Council to September 
1922 will be found stated in the Report for 1922, p. xxxi. Subsequent 
grants from the fund are incorporated in the lists of Eesearch Committees. 

In 1921-23, the Council authorised expenditure from accumulated 
income of the fund upon grants to Eesearch Committees approved by 
the General Committee by way of supplementing sums available from 
the general funds of the Association, and in addition to grants ordinarily 
made by, or applied for from, the Council. 

Sir J. K. Caird, on September 10, 1913, made a further gift of £1,000 
to the Association, to be devoted to the study of Eadio-activity. In 
1920 the Council decided to devote the principal and interest of this gift 
at the rate of £250 per annum for five years to purposes of tlie research 
intended. The grants for the year ending March 24, 1922 and 1923, 
were made to Sir E. Eutherford, F.E.S. The grant for the year ending 
March 24, 1924, was made to Prof. F. Soddy, F.E.S. The grant for 
the year ending March 24, 1925, was divided between Messrs. C. T. E. 
Wilson (£100), J. Chadwick (£75), and A. S. Eussell (£75). 



The following Resolutions and Recommendations were received and 
approved by the General Committee at Toronto, and, with the exception 
of the first, were referred to the Council for consideration, and, if desirable, 
for action. 

From Section B. 

That the sectional meetings on the Western Excursion be regarded as a part of the 
official programme of the Association. 

From Sections E, F, H and L} 
That the Council be requested to submit to His Majesty's Government and to the 
Universities Bureau that in any scheme for applying funds from the Boxer Indemnity 
to the provision of further facilities for higher education and research in China, account 
should be taken of the urgent need for the foundation of an institute in China for the 
purpose of education and research in geographical, economic and social conditions. 

Resolutions on International Service of Biological Abstracts. 

Section C approves in principle the proposals to establish an international service 
of biological abstracts as formulated by the Union of American Biological Societies, 
on the understanding that the biological (including systematic) side of palseontology 
will be included, as it already is in the Zoological Record, with which all possible con- 
tinuity should be maintained; further, it suggests to the Council that eventual details 
of arrangements and indexing should be reported on by the Association's Committee on 
Zoological Bibliography and Publication. 

Section D heartily approves in principle the proposal of the Union of American 
Biological Societies for the institution of an international comprehensive series of bio- 
logical abstracts, and recommends the General Committee to authorise the Council 
to take the necessary steps to bring about the collaboration of British workers. 

The Committee of Section D hopes that, in any such scheme, means may be found 
to preserve all possible continuity with the existing Zoological Record. 

Section H resolves : To ask the Council to support the jjroposal put forward by the 
National Research Council, U.S.A., for the institution of an international abstracting 
service for all biological sciences. 

Section I. — The Committee of the Section, which is in close touch with the Physio- 
logical Societies of both Great Britain and America, while it desired a sympathetic 
approach to our American colleagues in this matter, hoped the Physiological Section of 
the new Biological Abstracts would be arranged in co-operation with those responsible 
for the publication of physiological abstracts in England. The Committee desired that 
Prof. H. C. Bazett of Philadelphia be appointed as a member of the Publication Com- 
mittee of the proposed Abstracts, to make possible this co-operation, this appointment 
being made in response to the request of those speaking on behalf of biological abstracts. 

Section J. — The Section of Psychology cordially welcomes efforts to arrange inter- 
national co-operation in making and publishing abstracts of work bearing on psychology. 
Some progress has already been made by psychologists in this direction. The Section 
believes that there should be a considerable degree of national decentralisation. 

The Section further sympathises with plans for co-operation among the different 
biological sciences. It should be noted, however, that the relations of psychology are 
not only with the biological sciences, and psychologists would especially welcome 
methods by \vhich they could obtain abstracts of all papers bearing on psychology with- 
out subscribing for abstracts imrelated to it. 

Section K resolved : That the Committee of Section K heartily supports the pro- 
posal for the establishment of an International Journal for the Abstracting of Biological 
Publications, and instructs its representative (Dr. Rendle) to express this view to the 
Committee which is considering this matter in Toronto. 

Section M favours the general plan for a comprehensive Journal of Biological 
Abstracts as outlined in Science, of September 28, 1923, and presented to the Associa- 
tion by representatives of the American Union of Biological Societies, and accepts the 
invitation to appoint representatives on the Joint Publication Committee of the Union 
and the National Research Council of the United States. 

' The terms of the resolutions in-tbos group did not materially differ. 
( 12 FEB 25 ] 






My first duty is to thank the General Committee of the British Association 
for the great honour they have done me by electing me to the post of 
President. I must confess I wondered at first why I had been chosen, but 
soon came to the conclusion that it was an honour done through me to all 
Army Medical Officers for the magnificent work done by them during the 
Great War, in the prevention of disease and alleviation of pain and suffering. 

In the next place, I may be permitted to remind you that this is the 
fourth time the British Association for the Advancement of Science has 
met in Canada — first in 1884 in Montreal, in this city in. 1897, and in 
Winnipeg in 1909. 

The addresses given on these occasions dealt with the advancement of 
knowledge in Archseology and Physics. 

It is now my privilege, as a member of the medical [)rofessioii, to address 
you on the advances made during the same period in our knowledge of 
disease and our means of coping with and preventing it. 

An address on the prevention of disease at first sight does not promise 
to be a very pleasant subject, but, after all, it is a humane subject, and also 
a most important subject, as few things can conduce more to human 
happiness and human efficiency than the advancement of knowledge in the 
prevention of disease. 

Think for a moment of the enormous loss of power in a community 
through sickness. Some little time ago the English Minister of Health, 
when emphasising the importance of preventive work, said that upwards 
of 20,000,000 weeks of work were lost every year through sickness, among 
insured workers in England. In other words, the equivalent of the work 
of 375,000 people for the whole year had been lost to the State. When to 
that is added the corresponding figure for the non-insured population you 
get some idea of the importance of preventive work. 

1924 B 


Another way of estimating the value of prevention is in terms of 
dollars, or pounds, shillings, and jjence, and it has lately been calculated 
that the direct loss in England and Wales from sickness and disability 
amounts to at least 150,000,000/. a year. In the United States, with a much 
larger population, the loss is put down at 600,000,000/. 

Another reason why this is an important subject is that medicine in 
the future must change its strategy, and instead of awaiting attack must 
assume the offensive. Instead of remaining quietly in the dressing stations 
and field hospitals waiting for the wounded to pour in, the scientific 
services must be well forward in the enemy's country, destroying 
lines of comn^unication, aerodromes, munition factories, and poison- 
gas centres, so that the main body of the army may march forward in 

It must no longer be said that the man was so sick he had to send for 
the doctor. 

The medical practitioner of the future must frequently examine the 
man while he is apparently well, in order to detect any incipient departure 
from the normal, and to teach and urge modes of living conformable to the 
laws of personal health, and the Public Health Authorities must see to it 
that the man's environment is in accordance with scientific teaching. 

It may be a long time before the change is widely accepted, but 
already enormous advances have been efiected, and it only depends on 
the intelligence and education of the populations how rapid the future 
progress will be. 

Public opinion must be educated to recognise that most diseases are 
preventable and to say with King Edward VII., ' If preventable, why not 
prevented ? ' 

To our forefathers disease appeared as the work of evil spirits or 
magicians, or as a visitation of Providence to punish the individual or the 
community for their sins. 

It is not my purpose to give a detailed account of the first strivings 
after a better knowledge of the causes of disease, but it may be said the new 
era began some few hundred years ago, when it was recognised that certain 
diseases were contagious. 

For a long time it was held that this contagion or infection was due 
to some chemical substance passing from the sick to the healthy, and 
acting like a ferment ; and then, about the middle of last century, the idea 
gradually grew that microscopic creatures might be the cause. 

About this time it had been discovered that the fermentation of grape 


juice was caused by a living cell and that certain contagious skin-diseases 
were associated with living fungi. 

Things were in this position when there appeared on the scene a man 
whose genius was destined to change the whole aspect of medicine ; a 
man destined to take medicine out of the region of vague speculation and 
empiricism, and set its feet firmly on new ground as an experimental 
biological science. I mean the Frenchman, Louis Pasteur. It is from him 
we date the beginning of the intelligent, purposive prevention of disease. 
It was he who established the germ theory, and later ])ointed the way to the 
immunisation of man and animals, which has since proved so fruitful in 
measures for the prevention or stamping out of infectious diseases. 

I need not discuss his life and work further. His name is a household 
word among all educated and civilised peoples. Every great city should 
put up a statue to him, to remind the rising generations of one of the 
greatest benefactors of the human race. 

What the change in medicine has been, is put into eloquent language 
by Sir Clifford Allbutt : ' At this moment it is revealed that medicine has 
come to a new birth. What is, then, this new birth, this revolution in 
medicine ? It is nothing less than its enlargement from an art of observa- 
tion and empiricism to an applied science founded upon research ; from 
a craft of tradition and sagacity to an applied science of analysis and law ; 
from a descriptive code of surface phenomena to the discovery of deeper 
affinities ; from a set of rules and axioms of quality to measurements 
of quantity.' 

With one notable exception, the medical profession were not quick 
to see that Pasteur's discoveries of the nature of fermentation and 
putrefaction had a message for them. This exception was Joseph Lister, 
who had been for some years endeavouring to comprehend the cause of 
sepsis and suppuration, which commonly followed every surgical operation 
and most serious injuries involving a breach of the skin. 

When, in 1865, Lister read Pasteur's communication upon fermentation, 
the bearing of the discovery on the problems which had so earnestly 
engaged his attention was apparent to him. He inferred that suppuration 
and hospital gangrene, the causes of which had so far baffled his imagina- 
tion, were due to microbes introduced from the outside world, from the 
air, and by instruments and hands of the operator. Remember, this was 
years before the microbial causation of any disease was established. 

To test the correctness of his inference. Lister proceeded to submit all 
instruments, ligatures, materials for dressings, and everything that was 



to come directly or indirectly into contact with the wound, the hands of 
the operator, and the skin of the patient, to treatment with chemical 

The satisfactory results which followed this practice astonished even 
Lister, and he spent the rest of his active life in improving and simplifying 
technical methods of preventing the ingress of microbes to wounds, and in 
convincing his professional brethren of the truth of the conclusions based 
on this work of Pasteur. 


As soon as it was recognised that infectious diseases are caused by 
living germs a wave of enthusiasm swept through the medical world, 
and it was not long before the causation of many of the most important 
of them was discovered. I need not give a full list of these, but at or round 
about the time of the first meeting of the British Association in Canada 
the micro-organisms of tuberculosis, typhoid fever, Malta fever, cholera, 
malaria, diphtheria, tetanus, and others had been discovered and described. 

But it must not be assumed from what has been said that all the most 
important diseases are caused by living germs. Many of the ills that 
afflict mankind are due to quite other causes — alcoholism, for example, 
or the deficiency diseases, due to the absence or deficiency in our diet of 
some substance essential to proper growth and development. Rickets, 
one of the greatest scourges of industrial communities, is mainly a deficiency 
disease. It is reported that as many as 50 per cent, of the children in the 
slums of some of our big cities suffer from the effects of this disease. 

Then again, there is the whole series of diseases or conditions due to 
defective or excessive action of our own internal glands. 

Added to these, and perhaps the greatest scourge of all, there is the 
immense amount of chronic ill-health and actual disease caused or pro- 
moted by the unhealthy conditions found in our large cities, due to bad 
housing and overcrowding — the so-called diseases of environment. 

Malta Fever. 

But to return to the infectious diseases. After the living germs or 
parasites causing them had been isolated the process of prevention was 
soon begun. The methods employed were varied, and I may illustrate one 
of the simplest by relating briefly the history of the prevention of Malta 
fever, with which I was myself, to some extent, associated. 

Malta fever is really a widespread disease, although it is called by a 
local name. It is found all round the Mediterranean, throughout Africa as 


far south as the Gape Province, in India and China, and even in some parts 
o£ America. It was vc^'y prevalent in Malta in the old days, and rendered 
the island one of the most unhealthy of all our foreign military stations. 
When I arrived in Malta, in 1884, I found that every year, on an average, 
some 650 soldiers and sailors fell victims to it, and, as each man remained 
on an average 120 days in hospital, this gave the huge total of about 
80,000 days of illness per annum from this fever alone. 

The British had held Malta since the beginning of last century, and 
although much attention had been given to the fever and its symptoms 
had been fully described, no advance was made towards its prevention until 
1887, when the living germ, the Micrococcus melitensis, causing it was 

At this time a good deal of work was expended in studying the natural 
history of the fever and the micrococcus, but all to no purpose. Nothing 
was discovered to give a clue to any method of prevention. 

At the Naval Hospital especially everything in the way of prevention 
was done that could be thought of : the water supply and drainage were 
thoroughly tested, the walls were scraped and every corner rounded ofi 
where dust might lie, immaculate cleanliness reigned ; but all these 
precautions proved useless. Almost every sailor who came into the hospital 
even for the most trivial complaint took Malta fever, and after a long 
illness had to be invalided to England. 

Things remained in this very unsatisfactory state for seventeen years, 
until 1904, when the Admiralty and War Office, alarmed at the amount 
of sickness and invaliding in the Malta garrison, asked the Royal Society 
of London to undertake the investigation of the fever. This was agreed to, 
and a Commission was accordingly sent out in the same year and remained 
at work until 1906. 

During the first year every likely line of approach was tried. A careful 
study was made as to how the micrococcus entered the body, how it left 
the body, its behaviour outside the body, its pathogenic action on various 
animals ; but still no indication of a method of prevention showed itself. 

Next year, however, in 1905, the problem of prevention was solved, 
and that by the merest of accidents. 

In the previous year experiments had been made with the object of 
finding out if the goat, among other animals, was susceptible to the disease. 
The goats in Malta, which supply all the milk, are very much in evidence, 
as they are driven about in small herds and milked as required at the 
doors of customers. Several goats had been injected with cultures of the 


micrococcus, but, as they showed no rise oi temperature or any signs 
whatever of ill-health, they were put aside as being imnxune or refractory 
to the disease and nothing more was thought about them. 

In the spring of 1905, about six months after these experiments had 
been made, Dr. Zammit, a Maltese member of the Commission, who had 
kept one of two of these goats, happened for some reason or other to 
examine their blood, and found that it clumped or agglutinated the micro- 
coccus. This was strange, and seemed to show that, although the micro- 
coccus had not caused fever or any signs of illness in the goats, it must have 
lived and multiplied in the tissues of these animals in order to have brought 
about this change in the blood. 

This observation led to the re- examination of the immunity of the goat, 
when the extraordinary discovery was made that about 50 per cent, of the 
goats in the island were affected by this disease, and that 10 per cent, of 
them were actually excreting the micrococcus of Malta fever in their milk. 

Monkeys fed on milk from an affected goat, even for one day, almost 
invariably took the disease. 

Thus the weak link in the chain of causation had been found. The 
military authorities struck Maltese milk out of the dietary, and replaced 
it by an imported variety, and from that day to this there has scarcely 
been a case of Malta fever in the garrison. Malta, from being the most 
unhealthy of foreign stations, became a health resort, and was in fact 
used as a sanatorium during the late war. The disease had been blotted 
out at a single blow. 

This, then, is one way of preventing an infectious disease ; that is to 
say, by the discovery of the living germ, the study of its natural history, 
and so to a means of stopping it reaching its victim, man. This is the best 
way of prevention : shutting the stable door before the horse is stolen. 

Typhoid Fever. 

But there are other ways of preventing bacterial diseases. Let us take, 
for example, a method widely used in the prevention of typhoid fever. 

The fundamental and sound way of attacking this disease is by 
ordinary hygienic measures, especially a good water supply and good 
drainage. It is therefore one of the first duties of those in power to see that 
their people have, in addition to houses with plenty of light and air, a good 
water supply and a good drainage system, and money cannot be spent to 
better advantage than in the attainment of these three essentials to health. 

AVhen typhoid fever is rife in a community it means that there is 


either a contaminated water supply (jr u faulty drainage system, and thr 
nmnicipal authorities ought to be called to account. In England, owing 
to improved sanitation, cases of typhoid fever are fifteen times less than 
they were fifty years ago. 

But it is not always possible to ensure good hygienic surroundings — for 
example, among troops on active service. It is therefore legitimate under 
certain conditions, and especially in time of war, to practise a less sound, a 
less fundamental, method of prevention, and this second method is known 
as inoculation or vaccination. 

In order to understand how this acts, let us consider, for a moment, 
what takes place in a man's body when he is attacked by the typhoid 
bacillus. Everybody knows that the bacillus gives rise to poisons or toxins 
which cause the fever and other symptoms. But the cells and tissues of 
the man are not passive under the attack. They at once begin to fight 
against the infection, by forming substances in the blood to neutralise these 
toxins, hence called antitoxins or antibodies, and their function is finally 
to destroy the invading germs. If the man recovers he is immune from a 
further attack by the presence of these antibodies in his blood. He has 
become immune by passing through an attack of the disease. 

This is the foundation of the second way of preventing infectious 
diseases. Speaking broadly, it means that you subject a man to a mild 
attack of the fever in order that his blood and tissues will respond to the • 
stimulus by producing antibodies. 

This method takes its origin and name from that of vaccination against 
smallpox. Jenner solved that problem by the accidental discovery of 
vaccinia, a form of smallpox attenuated or weakened by passage through 
another species of animal. This weakening of the virulence of a micro- 
organism by passage through another kind of animal is by no means 
uncommon in nature. 

Pasteur, following on these lines, conceived the idea of weakening or 
attenuating the virulence of the living bacilli by artificial means, so as to 
give rise to a mild attack of the disease, and in this way to render 
animals immune. This he did with marked success in anthrax and chicken 

The next forward stop in this method of preventing disease was made 
Ijy Haffkine, a pupil of Pasteur, who about the year 1894 produced a 
vaccine against cholera, and a few years later another, against plague. 

In the course of this work it was discovered that it was not necessary 
to use living cultures of the bacilli, but that vaccines made uj) of dead 


bacilli had much the same effect. This substitution of the dead bacilli 
for the living was a great advance in the method, being much simpler 
*and much safer. 

The next disease to be attacked by this method was typhoid fever. 
This was initiated by Sir Almroth Wright at the British Army Medical 
School, and carried out with that scientist's characteristic ability and 
energy. The method was mainly directed in the first place to lessen the 
mortality from this disease among our soldiers serving in India. 

After several years' experience, the mode of inoculation which was 
finally settled on was to give two injections of dead typhoid bacilli, one of 
500 millions, and a second, at an interval of ten days, of a thousand millions. 

Now let us see what effect anti-typhoid inoculation has had on the 
prevention of typhoid fever among our soldiers in the field. 

In the South African War, at the beginning of the century, before the 
method had been developed, in an army the average strength of which was 
only 208,000 there were 58,000 cases of typhoid fever and 8,000 deaths. 

In the Great War, on the Western Front, with an average British strength 
of one and a quarter millions, there were only 7,500 cases and 266 deaths. 
In other words, there were fewer cases of the disease in this war than there 
were deaths in the South African. 

It is also interesting to learn from French sources that at the beginning 
. of the war the French soldiers were not inoculated, whereas the British were. 
The result for the first sixteen months was striking. During this time the 
French had some 96,000 cases, with nearly 12,000 deaths. The British had 
only 2,689 cases and 170 deaths. Afterwards the French soldiers were very 
thoroughly vaccinated, with the result that their immunity eventually 
became as striking as our own. 

What the number of cases and death-rate from typhoid fever might 
have been in the huge armies fighting on the different fronts had it not 
been for this preventive inoculation it is impossible to say, but undoubtedly 
the suffering and loss of life would have been enormous. 

I may therefore conclude this account of anti-typhoid inoculation by 
saying that it certainly constituted one of the greatest triumphs in the 
prevention of disease during the recent war. 

Tetanus and Diphtheria. 
I shall now pass on to consider a third method of preventing bacterial 
diseases which has also been evolved during the time under review ; 
that is, by the injection of specially prepared blood sera. These are known 


as antitoxic sera, and the most familiar examples are anti-tetanic and anti- 

We have seen how the injection of living or dead bacilli or their toxins 
into animals gives rise to the production of antibodies or antitoxins. The 
blood serum of such animals in virtue of the antibodies contained in it 
can be used to combat disease. 

Let us take in the first place the case of tetanus, until recently considered 
to be one of the most fatal of maladies, at least 85 per cent, of the cases 

As you are aware, anti-tetanic serum is prepared by injecting horses 
with large quantities of tetanus toxin. When the blood is as full as possible 
of antibodies it is drawn off and the serum allowed to separate out. 

The idea lying behind this third method of preventing disease is to 
pour in these ready-made antitoxins in order to assist the body in its first 
struggle with the invading disease, and give it, as it were, a breathing sjiace 
to prepare its own defences. 

Naturally the immunity produced by these antitoxic sera is of a passive 
nature, and of short duration, as compared with that produced by the 
disease itself, or even by the milder form brought about by vaccination or 

Anti-typhoid inoculation will protect a soldier for, let us say, two years ; 
anti-tetanic serum will protect for only a week or ten days. It is therefore 
impossible to inoculate a whole army against tetanus. It is necessary to wait 
until there is a danger of the disease occurring. 

To illustrate this I shall describe briefly the history of the prevention of 
tetanus during the Great War. 

When the British Expeditionary Force went over to France, in August 
1914, only a small quantity of anti-tetanic serum was taken, and that for 
the purpose of treatment rather than prevention. But shortly after the 
outbreak of hostilities the number of cases of tetanus among the wounded 
became so alarming that no time was lost in grappling with the danger. 
Large quantities of serum were hurried to the front, and some two months 
after the beginning of the war it was possible to make an order that every 
wounded man should receive an injection of anti-tetanic serum as soon after 
he was wounded as possible. Later on, after further experience had been 
gained, the single injection was increased to four, given at intervals of a 
week. This helped the wounded man over the dangerous time and the 
results were very successful. 

In August and September 1914, before the prophylactic injection was 


giveji, roughly speaking nine or ten out of every thousand wounded were 
attacked by tetanus and some 85 per cent, of these died. 

After the anti-tetanic injections had been introduced the incidence 
fell to little more than one per thousand, and the mortality to less 
than half. 

To put the matter broadly : during the war there were 2,500 cases 
of tetanus in the British Army, with 550 deaths. If there had been no 
prophylactic injection of anti-tetanic serum there would probably have 
been 25,000 cases with 20,000 deaths — a very striking example of the 
recent development in the prevention of disease. 

Another very important and widespread disease, somewhat resembling 
tetanus, is diphtheria, and there is no better example of the advance of 
science in methods of cure and prevention than is found in this 

Thanks to the work of Klebs and Loffler in the early 'eighties and, some 
years later, to the brilliant researches of Roux and Yersin, the causation 
and natural history of this disease were very thoroughly elucidated. 

Anti-diphtheritic serum is prepared much in the same way as the anti- 
tetanic. By the repeated injections of gradually increasing doses of the 
bacilli or their toxins, a serum is produced which has a marked curative 
effect in cases of diphtheria. 

It is stated that the introduction of anti-diphtheritic serum in 1894 
has reduced the death-rate from 40 to 10 per cent., and if used on the first 
day of the disease to almost nil. 

The serum is essentially a curative agent and is useful only to a limited 
extent in prevention. 

But lately essentially preventive measures in diphtheria have come into 
vogue. The procedure employed is to bring about an active immunisation 
by a mixture of toxin and antitoxin in individuals who have been shown 
to be susceptible to the disease by what is known as the Schick test. 

In the United States a campaign on these lines has been begun against 
this disease which promises brilliant results. It is confidently stated that 
by their new measures there is a possibility of robbing diphtheria of all its 
powers to kill or injure. 

The mode of prevention of these diseases — Malta fever, typhoid fever. 
and tetanus — illustrates the three principal methods of preventing bacterial 
diseases : in Malta fever, by getting down to bed-rock and stopping the 
disease at its source ; in typhoid fever, by giving, as it were, a mild attack of 
the di.sease, by vaccination or inoculalion, so as to bring about a greatf>r 


power of resistance ; in tetanus, by jKniring in antitoxins, already prepared 
in the serum of another animal, in order that they may neutralise the toxins 
of the invading bacilli as soon as they are formed. 


There are other important bacterial diseases, however, which cannot 
be attacked so simply. . For example, there is tuberculosis, a disease distri- 
buted over the whole world and one of the greatest scourges of civilised 
communities. It is a disease which has been known from time immemorial, 
but it is only within our own time that the bacterial cause has been recog- 
nised. I can well remember a day in 1882 when I met a fellow-student who 
had just returned to Edinburgh from Germany. He told me that it had 
been recently discovered that the disease was really caused by a living 
germ, the tubercle bacillus. It was difficult at first to believe such a 
revolutionary idea, but such was the interest and excitement raised that 
many workers at once took up the study of the subject and in a short time 
the truth of Koch's great discovery was fully proved. This was a magnifi- 
cent example of research work, most admirably, carefully, and completely 
carried out, and placed Koch at once in the front rank of scientific 

Before Koch's discovery a good deal had been done in the way of preven- 
tion. Before all things, this disease is a disease of environment. Its birth- 
place and home is the sunless, ill-ventilated, overcrowded room. The late 
Professor Edmund Parkes, Professor of Hygiene at the Army Medical 
School, reduced to a great extent the incidence of tuberculosis in the British 
Army by procuring for the soldier more floor-space and more air-space in 
his barracks. It is related of General von Moltke that when he heard of 
the death of Parkes he said that every regiment in Europe should parade 
on the day of his funeral and present arms in honour of one of the greatest 
friends the soldier ever had. 

The prevention of tuberculosis is thus seen to depend fundamentally 
on the provision of a better environment and the education of the people 
in physiological living. 

To attain this in the older civilisations will be a hard task, entailing 
enormous expenditure of money and energy. In the Re])ort of the Royal 
Commission on the Housing of the Industrial Population of Scotland in 
1917 is described the unsatisfactory sites of houses and villages, insufficient 
supplies of water, unsatisfactory provision for drainage, the gros.s over- 
crowding in the congested industrial towns, occupation of one-room houses 


by large families, groups of lightless and unventilated houses in the older 
burghs, clotted masses of slums in the great cities — a terrible picture, the 
heritage of the age of ignorance, internal strife, and walled towns. 

The people of new countries should see to it, and doubtless will see to it, 
that these old evils are not perpetuated. 

As Sir Robert Philip, Professor of Tuberculosis in the University of 
Edinburgh, has eloquently said : ' Were it possible to begin afresh the 
scheme of civilised life, were it possible to undertake anew the creation of 
cities and the homes of our people, were it possible to place within the 
re-created dwellings an understanding race, de-tuberculisation might be 
quickly attained. What a magnificent opportunity for the builders of the 
new cities, the moulders of fresh civilisations, with the grand purpose of 
" No tuberculosis." The architect, the sanitarian, and the citizen would 
agree in insisting that physiological laws should be paramount, that there 
should be efiective obedience to the larger demands of hygiene in the home, 
the school, the workshop, the meeting-place and the cow-shed. 

' Mankind was born into air and sunlight : these are his natural heritage. 
They are more — they are the irreducible conditions of life.' 

In regard to the tubercle bacillus it is so widespread, so ubiquitous in 
civihsed communities, passing from one infected host to infect another, 
that it would seem impossible under existing conditions to prevent its 
spread. At present it is taught, and on what seems good evidence, that the 
majority of the population of our crowded cities has at one time or another 
been attacked by this disease. But in every hundred men who die in 
England, only about ten die of tuberculosis, which shows that a large 
percentage of the population successfully resists the tubercle bacillus. 

When this occurs it means that the person attacked possessed powers 
of resistance which enabled him either to destroy the invading bacilli 
or to deal with them so as to render them harmless. 

A point of importance in this connection is that it has recently been 
demonstrated that the disease is usually acquired in childhood. The fact 
is of capital significance, for if the disease is recognised sufficiently early, 
and the child is placed imder good hygienic conditions, there is a very good 
chance of effective resistance and immunity against a second attack being 
set up. 

The present evidence goes to show that the presence of latent tubercle 
prevents a second invasion. If further outbreaks take place, they would 
seem to be due to a flaring up of the old latent tubercle rather than to a 
fresh infection. 


Metchnikoff studied the question in a remote part of Siberia where the 
tubercle bacillus was unknown. He states that very many of the young 
men and women who migrated from this clean country into the big cities 
died of acute and rapid tuberculosis, on account of not having been exposed 
to infection in their childhood. 

The experience of Colonial troops in the late war is instructive. Thus, 
in France the Senegalese, who are almost without tuberculosis in their 
native condition, and were found to be free from tuberculosis on reaching 
France, developed in large numbers an acute and fatal form of tuberculosis 
in spite of the hygienic measures enforced by the Army authorities. 

This raises a curious point. If it were possible for any country to clear 
itself of the tubercle bacillus, it would appear to be incurring a great risk 
for an inhabitant to migrate into any neighbouring country. 

But, in spite of this, it is the duty of medical men to keep in check, as 
far as possible, the ravages of the disease. 

The preventive measures against tuberculosis at the present time arc, 
in the first place, improvement in the general hygienic conditions. Thereby 
individual resistance — and communal resistance — can be remarkably 

In the second place, as every case of tuberculosis must arise from a 
previous case, either human or bovine, it is very necessary that methods 
of early diagnosis, preventive treatment, and segregation of the more 
infective types should be employed. This is done by the setting up of tuber- 
culosis dispensaries, care committees, sanatoria, hospitals and colonies. 
These several elements are combined in the model Tuberculosis Scheme 
which is now universal throughout Great Britain. 

In the third place, much can be done to anticipate and limit the 
progress of infection by the use of tuberculin, but caution is required 
in assessing the claims, sometimes hasty and extravagant, advanced by 
adventurers in this field of research. 

Many other points might be brought forward, but the subject is such 
a vast one that I must content myself with drawing attention to the 
importance of a sound milk supply. 

The contamination of our home herds with tuberculosis is so great 
that no pains should be spared to secure a safe milk supply, and I under- 
stand that the city of Toronto is a model in this respect. 

The result of these methods of prevention against tuberculosis may be 
given briefly. Sir Robert Philip writes that in Scotland ten years before 
Koch's discovery the death-rate from this disease was 404 per 100,000; 


ill 1920 it- had fallen to 124 per 100,000, a fall of 69-3 per cent. He also points 
out that the ' recent acceleration of rate of reduction which is noticeable 
in England and Scotland is of arresting interest." 

■ In Scotland the acceleration of fall in the mortality rate likewise 
arrests attention. Thus, during twenty years up to 1890, the percentage 
fall in mortality from all forms of tuberculosis was 35, while during twenty 
years from 1900-1919 the percentage fall was 45.' 

This is very satisfactory, and has only been arrived at by hard work 
on the part of medical men, nurses, and voluntary workers. Any Tuber- 
culosis Scheme, however perfect in theory, will require untiring energy, 
patience, and perseverance to bear fruit. On this side of the Atlantic, in the 
United States, these anti-tuberculosis schemes have been pursued with 
enthusiasm, with the result that Washington in 1920 had a death-rate, from 
all forms of tuberculosis for 100,000 of the population, of only 85, Chicago 
97, and New York 126. London in the same year had a death-rate of 127, 
practically the same as New York. Other nations have not been so energetic 
in preventive measures, Vienna having in 1920 a death-rate of 405 and 
Paris 279 per 100,000 from the same cause. 

It is evidently the duty of every nation to take up arms against a 
disease which exacts such a terrible toll of death, suffering, and inefficiency. 
If this were done with energy and enthusiasm it is not too much to hope 
that in a few generations the tubercle bacillus would be practically brought 
under control, and with it many other malign influences. 


I shall now pass on to the consideration of the second great group of 
infectious diseases, the Protozoal, and consider what methods of prevention 
have been found applicable to them. 

The scientific study of the protozoal diseases of man may be said to 
have begun with the epoch-making discovery of the malaria parasites in 
1880, by the illustrious Frenchman, Laveran ; next, in 1893, the discovery 
by Theobald Smith and Kilborne of the cause of Texas fever and the part 
played in its dissemination by the cattle- tick ; in 1894 the discovery of the 
trypanosome of nagana and its intermediate insect host the tsetse-fly ; in 
1898 the working out of the development of the malaria parasite of birds 
in the mosquito by Ronald Ross, greatly aided and abetted in the work by 
Patrick Manson, which led, through the work of Grassi and his fellow- 
w^orkers in Italy, to the final solution of the malaria problem. A year later 
the important discovery of the mosquito carrier of yellow fever was made 

THE prp:sidkntial address. IT) 

by the American Army Coinmissiou, under the directorship uf Reed, and 
in 1903 T>eishniau announced his discovery of the protozoal cause of kala- 

These protozoal diseases are world-wide, like tlie bacterial, but it is 
in the warmer climates that their effect is most felt. 

The great plagues of the tropics, such as malaria, amoebic dysentery, 
kala-azar, and sleeping sickness among men, Texas fever, tsetse-fly disease, 
and others among domestic animals, are caused by minute microscopical 
animal parasites. 

Large tracts of country have been and arc still rendered uninhabitable 
to white settlers by their presence. 

The opening up of Africa, for example, was rendered difficult by the 
tsetse-fly, before the advent of railways. No sooner had an expedition 
started for the interior than the fly attacked the cattle transport, and 
before long the expedition had to make its way back as best it could to 
its base on the coast. The only way to get into the country was on foot 
with native porters. 

The protozoal diseases of domestic animals have also led to enormous 
loss in all parts of the world. Texas fever, or red-water, has swept 
whole countries of their cattle. After the Boer war, South Africa was 
devastated by the introduction of East Coast fever, another protozoal 
disease of cattle closely related to Texas fever. 

How is the prevention of these diseases to be brought about ? We 
find that up to the present little can be done by way of vaccination or 
inoculation or by the use of anti-sera as in the bacterial diseases. On 
studying the natural history of these protozoal parasites, however, it is 
found that many of them depend on an intermediate insect host for their 
continued existence, and it is by taking advantage of this characteristic 
that methods of prevention can be devised. 

To illustrate this, I might cite the classical examples of malaria and 
vellow fever, but, as these must be familiar to you all, I shall take instead 
thetry])anosome diseases of Africa, the best known of which are sleeping 
sickness in man and nagana or tsetse-fly disease in the domestic animals. 

Nagana or Tsetse-fly Disease. 

In 1894, a year after Theobald Smith and Kilborne had published 

their famous monograph on Texas fever, a severe epidemic among native 

cattle in the north of Ziduland was reported to the Natal Government. 

The disease was call(>d nagana by the natives, and it is curious that there 


was no suspicion at the time that it had any connection with the 

At this time a very enlightened administrator, the late Sir Walter 
Hely-Hiitchinson, was Governor of Natal and Zululand, and it was due to 
him that the investigation of the cause of the Zululand outbreak was at 
once undertaken. 

As I happened to be stationed in Natal at this time, I was chosen to 
undertake the work, and at once started on the long journey, mostly by 
ox- wagon, to the scene of the outbreak. 

On examination of the blood of the nagana cattle, a minute active 
flagellated protozoal parasite, belonging to the genus Trypanosoma, was 
discovered, and after many experiments on dogs, horses, and cattle it was 
decided that in all probability it was the cause of the disease. 

Trypanosomes had previously been described in the blood of rats and 
horses in India by Timothy Lewis and Griffith Evans, but nothing was 
known as to the mode of their transmission from animal to animal. 

It seemed as if the discovery of the nagana trypanosome would have 
ended the investigation in Zululand without any means of preventing the 
disease being discovered, but another observation made at this time threw 
more light on the subject. 

In the low country between the high ground, on which the nagana camp 
was situated, and the sea there happened to be a so-called ' Fly belt.' 

Every schoolboy had read about the tsetse-fly in books of travellers 
and hunters, especially in those by the most famous of them all, David 
Livingstone the missionary, and out of curiosity I decided to find out what 
happened when an animal was bitten by the fly, or, as it was termed, fly- 

Natives were therefore sent with cattle and dogs into this ' fly country,' 
with orders to form a camp and expose the animals to the bites of the fly. 
This was done and it was with great surprise that on their return to the hill 
the blood of these fly-struck animals was found to contain the same parasite 
as that found in the nagana cattle. 

Nagana and tsetse-fly disease were finally proved to be identical. The 
tsetse- fly disease was shown to be caused, not, as had been believed, by the 
poisonous bite of the fly, but by the transference of a protozoal parasite 
from the fly to the animal in the act of sucking blood. 

Now the question arose as to where the fly found the parasite. As 
the tsetse-flies constantly lived among and fed on wild game, such as buffalo 
and antelope, these animals were suspected. Their blood was examined, 


and before long it became evident that the wild animals acted as the 
reservoir of the disease, the trypanosomes living in their blood as harmless 
parasites. When the tsetse-fly fed on blood containing the trypanosome 
it became infected, and was capable by its bite of giving rise to a fatal 
disease in cattle, horses, or dogs ; whereas if it fed on a wild animal nothing 
happened, as the wild game are immune to the disease, much in the same 
way as the goat is immune to Malta fever. 

Now that the natural history of the disease had been so far worked out 
it was evident that its prevention might be attempted. 

This can be done in any of three ways : by getting rid of the wild game, 
the reservoir ; or by getting rid of the fly, the vector or carrier ; or, lastly, 
by removing the cattle, horses, and dogs to a safe distance from the ' fly 

This work on nagana led later, in 1903, to the discovery of the cause and 
mode of prevention of sleeping sickness. 

Sleeping Sickness. 

About the beginning of the century an epidemic of this disease raged 
round the shores of Lake Victoria in Central Africa. It had been introduced 
into Uganda from the West Coast, where it had been known for many years 
as a curious and unaccountable disease. It was observed that although 
the disease spread in a West African village from man to man apparently 
by contact, no such thing occurred among natives exiled from their homes. 
The disease never spread if introduced into native compounds in the 
West Indies or America, however closely the slaves might be herded 

The disease remained shrouded in mystery and nothing had been done 
in the way of prevention, until the matter was taken up by the Royal 
Society of London in 1902 and a Commission sent out to investigate. 

It is not necessary to go into details ; suffice it to say that after one or 
two false starts the Commission in 1903 came to the conclusion that the 
disease was caused, as in nagana, by a species of trypanosome. 

The question of the distribution of sleeping sickness in Uganda was 
then taken up. This disclosed the remarkable fact that the disease was 
restricted to the numerous islands in the northern part of the lake and 
to a narrow belt of country skirting the shores of the lake. In no part of 
Uganda were cases found more than a few miles from the lake shore. 

The next important step in the working out of the etiology was made 
when it was shown that the distribution of the disease was identical with 

1924 *-' 


the distribiition of the common tsetse-fly of the country, Glossina palpalis. 
Where there was no fly there was no sleeping sickness. 

The problem was now solved. The epidemic could be stopped either 
by getting rid of the fly or by removing the natives out of the fly area. 
As the destruction of the fly was impracticable under the circumstances, 
the second method was decided on. The natives were moved from the 
islands and lake shore and placed on healthy inland sites, and the epidemic, 
which had cost the Protectorate some 200,000 lives, speedily came to 
an end. 

This method of preventing disease, by removing man out of the zone 
of danger, is an extravagant one, and can only be done in exceptional 
circumstances. In Uganda the native population could be easily moved, 
but it meant that from about 1910 until the present day som_e of the most 
fertile land in Uganda has been lying derelict, has returned to the primitive 
jungle. The war delayed things, of course, but it is only now that the 
natives are being returned to their old homes on the islands and lake shore, 
in the hope that the fly by this time has lost its infectivity. 

The other method, by the destruction of the tsetse-fly, has been carried 
out successfully in other places. For example, in the island of Principe, 
off the West Coast of Africa, by destroying the wild animals which supplied 
a large part of the food of the fly and by clearing the jungle the tsetse- 
flies disappeared, and with them the disease. 

This is the method employed in malaria and yellow fever. It was by 
destroying the mosquito carrier that Gorgas drove yellow fever out of 
Havana and, later, both malaria and yellow fever from the Panama Canal 

Thus through the work of Manson, Laveran, Ross, Reed, and others 
has it been made possible to deal with these two scourges of the tropics, 
malaria and yellow fever. 

I include yellow fever among the protozoal diseases, although Noguchi 
in 1919 brought forward strong evidence that it is caused by a spirochaete. 

In regard to yellow fever the victory has been almost won. During 
the last century this disease, known as 'yellow jack,' devastated the West 
Indies and Central and South America. 

At the present time, thanks chiefly to the unremitting efforts of the late 
General Gorgas and the International Health Board of the Rockefeller 
Foundation, the disease has been driven out of the West Indies and Central 
America, and only retains a precarious foothold in Colombia and Brazil, 
whence it will doubtless be ejected during the next year or two. 


One of the best examples of the prevention of disease is the attack 
made on yellow fever in Rio de Janeiro, the capital of Brazil, by the 
well-known scientist, Dr. Oswaldo Cruz, with the result that the annual 
deaths in the city from yellow fever fell from 984 in 1902 to in 1909. 
This brilliant result was brought about by the destruction of the 
Stegomyia mosquito, the intermediate insect host in yellow fever. 

So also in the case of malaria. A dozen years ago, based on the 
experience gained by Ross on the West Coast of Africa and Ismailia and 
by Watson in the Federated Malay States, the method of prevention by 
mosquito control and drainage has been so perfected that the practical 
blotting out of malaria from a given locality is now merely a matter of 
expense. A great deal of work has been done during the last few years 
in the way of experiment in the United States, and Vincent, the President 
of the Rockefeller Foundation, lately stated that there is evidence that 
' under normal conditions an average community can practically rid itself 
of malaria at a per capita cost of from 45 cents to $1 per year.' 

This is an altogether inadequate account of the methods of preventing 
these highly important protozoal diseases. From the few examples given, 
it will be seen that they are most rampant in warm climates, that they 
are as a rule conveyed from the sick to the healthy by an insect interme- 
diary, and that it is by an attack on this insect, be it mosquito, tsetse-fly, 
or tick, that the best chance of success in prevention lies. 


In addition to the bacterial and i)rotozoal infectious diseases, there is a 
third and large class, known as the ' undetermined group,' in which the 
parasite is either unknown or doubtful. Many of these undetermined 
diseases are very common and familiar, such as influenza, measles, scarlet 
fever, smallpox, typhus fever, trench fever, dengue fever, and sand-fly 
fever ; among animals, rabies, rinderpest, foot-and-mouth disease, and 
African horse-sickness. 

The theory generally held at present in regard to most diseases included 
in this group is that the living germs causing them are ultra-microscopical, 
in at least some part of their life history, and this is strengthened by the 
fact that many of them pass through porcelain filters, which keep back the 
smallest of the visible bacteria. Hence the name, ' filter-passers.' 

Many of these undetermined diseases are highly infectious and appear 
to infect at a distance through the air, as, for example, in influenza, 
scarlet fever, and smallpox. 


In some of them there is no attempt made at prevention, except that the 
sick are isolated and placed under quarantine for a longer or shorter period. 
But in others there are well-known methods of prevention even when 
the virus is quite unknown. The best example is smallpox, the ravages 
of which have been completely held in check since the memorable discovery 
of Jenner. As has already been argued, this method of prevention, by 
inducing a mild or attenuated form of the disease, is at best a clumsy one, 
and when the natural history of the smallpox virus is better known it 
may be hoped that a more fundamental method of preventing this disease 
may be discovered. In the meantime the best means at our disposal is 
by the use of vaccine lymph, and people should recognise their responsi- 
bility to the community if through ignorance or selfishness they refuse 
to have their children vaccinated. 

Another well-known disease with an unknown virus, rabies or hydro- 
phobia, has also, by the genius and intuition of Pasteur, been robbed of many 
of its terrors. The mortality following bites of rabid animals has fallen 
from 16 per cent, to less than 1 per cent. 

But in rabies, when the conditions arc favourable, the radical method 
is to drive the disease altogether out of the country by the careful adminis- 
tration of muzzling and quarantine laws. This was carried out successfully 
in England at the beginning of the century. 

Trench Fever. 

There are among the diseases of undetermined origin a few which are 
slowly emerging from the unknown into the known. One of the most 
interesting of these is trench fever, which came into great prominence 
during the war. 

The history of the investigation of this fever is interesting, and 
well illustrates the method of studying a disease with a view to its 

Before the war, trench fever was unknown, though there is some 
evidence that it had been recognised at an earlier date in Poland and called 
Wolhynia fever. Be that as it may, it is quite certain that, though it was 
unknown on the Western Front at the beginning of the war, it is no 
exaggeration to say that it became one of the most powerful factors in 
reducing our man-power, probably more than a million cases occurring 
among the Allies on the Western Front. In 1917 in the Second British 
Army alone, out of a total of 106,000 admissions to hospital at least 
20,000 of the cases were trench fever. 


Although thia fever has well-marked characteristics of its own, such 

as a peculiar type of temperature curve, and other symptoms, yet for a 

long time it was unrecognised as a separate entity, and remained mixed 

up with other diseases, such as typhoid fever, malaria, and rheumatism. 

In 1916 MacNee, Renshaw, and Brunt in France made the first definite 
advance by showing that the blood of trench-fever cases was infective. 
They succeeded in transferring the disease to healthy men by the injection 
of the blood. The most careful microscopic examination of the blood 
corpuscles and lymph failed, however, to reveal any living germ. 

Nothing more was done until the following year, when the British War 
Office took the matter up seriously and formed a Committee for the purpose 
of investigating the disease. 

The United States of America, on coming into the war, at once recog- 
nised the importance of trench fever, and without delay also undertook 
its investigation. 

In October 1917, at the first meeting of the Medical Research Com- 
mittee of the American Red Cross in Paris, Major R. P. Strong recom- 
mended that a research into trench fever should be undertaken. He stated 
that, after several months' study of the problems relating to the prevention 
of infectious diseases occurring in the Allied Armies on the Western Front, 
it became evident that the subject of the method of transmission of trench 
fever was one of the most important for investigation in connection with 
the loss of man-power in the fighting forces. 

At the next meeting, in November 1917, this was agreed to, and a 
Trench Fever Committee, under the chairmanship of Major Strong, was 
formed. The research was organised, and experiments begun on Febru- 
ary 4, 1918. In less than six months the investigation was completed 
and the report in the hands of the printer. This is a striking example of 
research work which, if carried out at the beginning of the war instead of at 
the end, might have saved the Allied Armies hundreds of thousands of 
cases of disease, which, although never fatal, were often of long duration 
and led to much invaliding. 

The most important result of the work of these two Committees was that 
it was amply proved that the louse, and the louse alone, was responsible for 
the spreading of the disease. This discovery meant that in a short time 
trench fever would have disappeared from our armies on the Western Front- 
Just as the elimination of goat's milk blotted out Malta fever, the 
elimination of the mosquito malaria and yellow fever, so would the 
elimination of the louse have completely blotted out trench fever. 


This method of prevention, by the destruction of the louse, although 
doubtless requiring careful organisation and energy in carrying out, was 
shown before the end of the war to be a perfectly practicable proposition, 
and there can be little doubt that, if the war had lasted much longer, trench 
fever, like tetanus, would have practically disappeared. 

Besides the main discovery from the preventive point of view that the 
louse is the carrier, there are many other points of interest in the natural 
history of trench fever. 

The living germ causing it has never been recognised in the human blood 
or tissues, probably on account of its extreme minuteness, and its conse- 
quent liability to confusion with other small granules. 

But when the louse sucks blood from a trench-fever case there is 

apparently a great multiplication and development of the supposed 

micro-.ts'ganism. In five to nine days the louse becomes infective, and there 

is seen m the stomach and intestines enormous numbers of very minute 

ibodies. What the exact nature of these bodies is, is unknown, but there 

cao be little doubt that they are the infecting agents by which the louse 

passes on the disease. They j^ass out in countless numbers in the droppings 

or excreta of the louse, and it is to these bodies in the excreta that infection 

is due. The louse seldom if ever gives rise to the disease in the act of biting. 

It is the infective excreta thrown out on the skin which causes the infection. 

'The micro-organisms or so-called Rickettsia bodies contained in the 

t excreta find their way into the blood through abrasions or scratches, and 

ISO give rise to the fever. 

From what has been said it will be seen that trench fever is an interest- 
ing disease. It also explains why it disappears in times of peace. As soon 
as the war was ended, and our men could leave the trenches and resume 
their normal habits, the disease disappeared. The louse was eliminated and 
the trench fever with it. 

Typhus Fever. 

Another disease of the undetermined group closely related to trench 
fever and also carried by the louse is typhus fever, one more of the furies 
following on the heels of war. The French and British Armies escaped this 
scourge to a great extent, but some of the other countries, such as Serbia, 
Bulgaria, and Poland, were not so fortunate. It is stated that 120,000 
Serbians died of this disease during the war, and it was only after vigorous 
steps had been taken in sanitary measures directed against the louse that 
the epidemic was got in hand. 


After the long, exhausting Napoleonic wars, with the resulting poverty 
and destitution, typhus fever was prevalent in Great Britain and Ireland. 
About the middle of the century the improved economic conditions 
gradually led to the disappearance of the disease in Britain, although 
cases still occur in some parts of Ireland. 

It is to NicoUe that we owe the advancement in our knowledge of this 
important disease. His work in Tunis on this subject dates from 1909. 
He showed that the blood of typhus cases is infective to monkeys, and, most 
important of all, that the infection takes place through the body louse. 
Just as in trench fever, the louse becomes infective after some five days, and 
it has been shown by the late Arthur Bacot of the Lister Institute that 
the excreta is also infective. 

The minute bodies found in the typhus louse are, subject to some 
differences, very similar to those found in the trench-fever louse and have 
been named Rickettsia proivazeki by Rocha Lima. What group these 
bodies belong to is still a matter of discussion. Some consider them to 
be protozoa, with an ultra- microscopical stage in man and a developmental 
stage in the louse, while others look on them as minute forms of bacteria. 

Although there is still some doubt as to the pathological significance 
of these Rickettsia bodies, the work of Sargent, Rocha Lima, Arkwright 
and Bacot, Wolbach, Todd and Palfrey has done much to establish a 
causal relationship between them and these two diseases, typhus and 
trench fever. 

From the point of view of prevention, the important fact is that the 
infection is carried by the louse, and in the next great war it will be almost 
as necessary to prepare means for the destruction of the lice as of the 


Rocky Mountain Fever. 

A third disease belonging to this interesting little group — Rocky 
Mountain fever — occurs in certain localities in the United States. It 
provides another instance of a virus transmitted by an invertebrate host 
to man. As the result of the work of Ricketts and of Wolbach the wood- 
tick, Dermocentor venustus, is now recognised as the vector. Rickettsia 
bodies closely resembling those found in association with typhus and 
trench-fever virus have been shown to be present in the stomach and 
tissues of the tick, and the same bodies have also been demonstrated in the 
tissues of infected guinea-pigs. 

Another interesting disease of the undetermined group is sand-fly 
fever, the virus of which is conveyed from man to man by the sand-fly. A 


new era in its study lias been opened up by the work of Whittingham and 
Rook, who have learned how to handle, breed, and keep sand- flies in cap- 
tivity, and have shown that the virus is transmitted from generation to 
generation of flies without intervening passage through man or other higher 
animal. The knowledge of the life history of the flies will no doubt lead 
in due course to the suppression of the disease. 

Another type of invertebrate vector is the Kedani mite, Trombicula 
akamushi, which transmits the virus of Japanese river-fever to man from 
wild animals. The dangerous character of this disease (Tsutsugamushi) 
and the minute size of the mite together have presented great difficulties 
to the Japanese investigators. Protection from the mite by special 
clothing and bathing after exposure to risk of infection are at present the 
most hopeful methods of prophylaxis. 

Antitoxic sera have also been used with some measure of success in 
the prevention of diseases of this group. Degkwitz and others in 
Germany are reported to have been very successful in protecting 
children from measles and scarlet fever by injecting them with a small 
quantity of serum from convalescent patients. This method has also 
been found very useful under suitable conditions to protect cattle from 
foot-and-mouth disease. 

But far more hopeful than protection by serum alone is the use of a 
vaccine to produce a lasting immunity, combined with antitoxin to prevent 
the vaccine from producing unpleasant results- — the so-called toxin-anti- 
toxin method. Most of the diseases for which this method of prophylaxis 
has proved valuable have been diseases of animals, suchaspleuro-pneumonia 
of cattle, rinderpest, and foot-and-mouth disease ; but quite recently the 
method of Dick, of Chicago, in scarlet fever has been supported by a number 
of observations. The system of testing and producing immunity is planned 
on the same lines as the Schick method for diphtheria. 


The preceding account is but a short and meagre history of the mar- 
vellous advance which has been made in the prevention of infectious 
diseases in our times, an advance due in great part to the work of two 
men, Pasteur the Frenchman and Koch the German ; those who have 
come after them have merely followed in their footsteps, been their 

Time will not permit even to touch upon the advances made in the pre- 
vention of other important diseases, such as the surgical infections and 


those caused by intestinal parasites, prominent among which are the 
hookworms and bilharzia. 

This advance has not been limited to the infectious group : it has been 
shared by other groups, notably those due to dietetic deficiencies, the so- 
called deficiency diseases. These deficiency diseases are just as important, 
or even more important, than the infectious, since they are always with 
us and exact an enormous toll in lowered health, lowered vitality, mal- 
formation, and inefiiciency. 

Until a few years ago it was taught in the schools that a complete diet 
consisted of certain proportions of proteins, carbohydrates, fats, and salts. 
But our knowledge is constantly increasing, our ideas about things con- 
stantly changing, and what is looked on to-day as absolute immutable 
truth to-morrow is seen in the light of some newer knowledge to be but a 
crude beginning. So the teaching concerning what constitutes a complete 
and healthy diet has changed, inasmuch as certain substances have been 
discovered in food-stuffs in the absence of which an adequate number of 
calories supplied in the form of proteins, carbohydrates, fats, and salts can 
alone neither promote growth nor support life indefinitely. These acces- 
sory food factors, or vitamins as they have been named, are present in such 
minute quantities in foods that they have never been isolated, and their 
chemical composition is therefore unknown. It is still a matter of opinion 
as to whether they really constitute parts of the structure of living tissues, 
or whether they merely act as catalysts or stimulators in the processes 
of growth and metabolism. That they are definite chemical substances 
which can be added to or removed from a food-stuflf, with good or evil 
results, has, however, been abundantly proved. 

The untutored savage living on the natural fruits of the earth and the 
chase knows no deficiency diseases. It is only when man begins by arti- 
ficial means to polish his rice, whiten his flour, and tin his beef and vege- 
tables that the trouble begins. Civilised man living in comfort, drawing 
his food supply from the whole earth and able to vary his dietary at will, is 
in little danger ; but it is otherwise with children and adults living under 
institutional conditions, with armies on active service, encountering 
extremes of climate, and with young infants on their naturally restricted 
diet. While it is true that deficiency diseases will only develop to their 
well-marked dangerous stage if the deficiency of accessory factor is severe 
and protracted, a slighter deficiency, if prolonged, may cause a condition 
of general ill-health and inefficiency not less important although ill defined 
and difficult to diagnose. This fact is of special importance in the case of 
infants and young children. 


The Discovery of Vituinins. 

At the present time, three, and possibly four, distinct vitamins have been 
described and studied, and it is probably only a matter of time for others 
to be discovered. 

The discovery of vitamins dates to the middle of the 18th century. 
In 1747 James Lind, a surgeon in the British Navy, carried out a series of 
experimental observations upon sailors suffering from scurvy, the concep- 
tion and performance of which were entirely admirable. By appropriate 
control experiments he showed that the medical means in vogue for the 
treatment of the disease were futile, when not harmful, but that orange 
and lemon juices were a specific cure. Lind attempted to ascertain the 
relative anti-scorbutic value of various fruits and green vegetables, but was 
unable to observe a ' superior virtue ' in one rather than in another. He 
confirmed Kramer's observations made at the beginning of the 18th century, 
during the war between the Turks and the Holy Roman Empire, that dried 
vegetables were useless, and adopts the explanation of his friend Cockburn 
' that no moisture whatever could restore the natural juices of the plant 
lost by evaporation,' which Cockburn imagined were ' altered by a fer- 
mentation which they underwent in drying.' 

Lind was struck with the beneficial effect of cow's milk in the treatment 
of scurvy. He explained it on the supposition of the milk ' being a truly 
vegetable liquor, an emulsion prepared of the most succulent wholesome 

Lind applied himself to the applications of these discoveries for the 
prevention of scurvy in the Navy, and recommended lemon-juice con- 
centrated to a syrup by evaporation to be carried in all ships and served 
out to the sailors. 

By the beginning of the 19th century the carriage of lemon-juice was 
made compulsory, first in the Navy and subsequently in the mercantile 
marine, with the result that the ravages of scurvy were prevented. With 
the advent of steam traction, too, the length of voyages was curtailed and 
supplies of fresh provisions were obtained at more frequent intervals. 
Scurvy became rare, and the medical profession, being no longer faced with 
this disease of dietary deficiency, soon forgot the significance of Lind's 

Before leaving this subject a curious fact may be related. The lemon- 
juice supplied to the Navy was at first made from lemons grown in Spain 
and the Mediterranean countries. Afterwards, when England took over 


the West Indies, it was made from the lime, and scmvy again broke out. 
The reason of this is now known to be that whereas the lemon is par- 
ticularly rich in anti-scorbutic vitamin, the lime is correspondingly poor. 

The scientific study of the disease may be said to have lapsed for a 
century and a half, until Hoist and his co-workers in Copenhagen investi- 
gated the etiology of scurvy anew on modern lines, with the help of experi- 
ments on animals. Their work, published in 1907 and 1912, formed the 
basis for the numerous researches carried out in England and America 
during and since the recent war. As a result of this work the etiology of 
scurvy, discovered in effect centuries earlier, has been firmly established 
as due to lack of a specific, undetermined, and as yet unisolated, constituent 
of fresh foods, especially of fresh vegetables and fruits, now known as 
Vitamin C. 

In the meantime the existence of a second vitamin, the so-called anti-beri- 
hcri, or anti-ueuritic vitamin. Vitamin B, had been discovered. Eijkman's 
admirable studies at the end of last century, in 1897, on the etiology of beri- 
beri in the Dutch Indies brought forward evidence for the view that this 
disease was of dietetic origin, and was caused by a diet consisting too 
exclusively of highly milled and polished rice. He showed that the 
disease could be prevented if the outer layer (or pericarp) and the embryo 
of the seed, which had been removed in the process of milling, were restored 
to the ' polished ' rice. Eijkman's discovery of the analogous disease in 
birds. Polyneuritis gallinarum, provided the necessary tool for further 
investigation of the subject. The researches of Grijns and others showed 
that the bran and polishings of rice were only one of many rich natural 
sources of theunknown principle preventing beri-beri, and it became e\adent 
that, while the disease is usually confined to tropical races subsisting largely 
on rice, the European white-bread eater is protected only by the varied diet 
he usually enjoys. Experience on active service shows that beri-beri may 
really develop on a diet of tinned meat and white bread or biscuit. 

During the late war two examples of the use made of this new knowledge 
occurred in Mesopotamia. At the beginning of the campaign, on account 
of a difficulty in transport, there was a shortage of fresh food, with the 
curious result that scurvy broke out among the Indian troops and beri-beri 
among the British. The Indians were living on dried pulses, such as peas, 
beans, and lentils ; the British on tinned beef and biscuits. The former 
diet was deficient in the anti-scorbutic vitamin on account of the complete 
drying of the seeds ; the latter in the anti-beri-beri factor on account of the 
use of white flour from which the germ had been removed. 


Some years ago it had been discovered that if dried seeds are germi- 
nated, a quantity of the anti-scorbutic vitamin is produced by the act of 
sprouting. This was done. The dried peas and beans were soaked in water 
and then spread out in shallow layers, to cause them to sprout, which they 
readily did in the warm climate. The germinated seeds were then issued 
to the Indian troops and cooked in the usual way. As a result of this simple 
procedure the scurvy completely disappeared. 

In regard to the British troops it was known that the anti-beri-beri 
vitamin is contained in large quantities in certain cells, and notably in 
yeast cells. A small quantity of this substance in the form of marmite was 
added to the soldier's diet of bully-beef and biscuits, and the beri-beri 
in like manner disappeared. 

It may seem strange that the conception of the role of vitamins in 
nutrition should have come first from the pathologist, and should not have 
emerged from the important advances in our knowledge of the physiology 
of nutrition which were made during the second half of the last century. 
The physiologists were preoccupied with the chemical composition of 
food-stuffs and their value for supplying energy and supporting growth, 
and with the necessity for supplying the requisite number of calories in a 
diet, distributed appropriately among proteins, fats, and carbohydrates, 
with adequate selection of mineral salts. It was only when these researches 
led to experiments in which animals were fed upon various mixtures of 
purified food elements that the investigators in this field began to realise 
that their rejjeated failures to rear animals upon such carefully arranged 
diets were not due to accident. The truth was suspected by Lunin in 1881, 
but it was not until 1912 that Hopkins published the classic experiments 
which proved the fact beyond a doubt. In the course of work along the 
same lines in the United States, McCoUum and Davis in 1915 rediscovered 
Vitamin B, and, in addition, a third essential dietary constituent, a fat- 
soluble vitamin, present in butter-fat and certain other fats of animal 
origin, especially in cod-liver oil and other fish oils. This vitamin is known 
as fat-soluble Vitamin A. 

Rickets as a Deficiency Disease. 
The discovery of the fat-soluble vitamins proved to be of great import- 
ance in elucidating the etiology of this disease, which had for long been an 
unsolved problem. Some authorities had erroneously considered it to be an 
infectious disease, like tuberculosis. Another school held the so-called 
Domestication Theory, that it was caused by unnatural surroundings, 
involving a want of sunlight, fresh air, and exercise. A third considered 


rickets to be caused by improper feeding, though opinions differed as to the 
exact nature of the dietetic defect. The conclusion, first put forward by 
Mellanby in 1918, that a deficiency of fat-soluble vitamins plays a most 
important part in the causation of the disease is now generally accepted. 
This has been established by a large amount of work, both experimental 
and clinical, carried out by Mellanby himself, McCollum and Hess and their 
respective co-workers in the United States, and Korenchevsky and others 
in England. It may be laid down that if a young animal is supplied with a 
sufficiency of these vitamins, rickets will not develop. The question of 
prevention is therefore one of economics. The difficulty is that these fat- 
soluble vitamins are chiefly found in such food-stuffs as butter, eggs, the 
fat of beef and mutton, and fish oils, all expensive articles of diet which the 
poorer classes can seldom afford. The only ' butter ' used by them is 
probably some form of margarine, made from vegetable oils which contain 
little or no anti-rachitic vitamin. The question of prevention is for the 
sociologist. Science can only discover the causes and point the means. 
It is for governments and local authorities to carry out preventive measures 
in practice, and it is to be feared that science is often far ahead of the 
community in its share of the work. 

Although the theory that rickets is an infectious disease has been 
exploded, a great and remarkable truth was contained in the domestication 
and hygienic theories which held that, among other unhygienic conditions, 
want of sunlight was concerned in the etiology of the disease. During the 
last five years it has been discovered that exposure to sunlight or to the 
ultra-violet ra3's of the mercury vapour quartz lamp can cure rickets in 
children. Experiments on animals have shown that the effective rays in the 
sunlight are also the ultra-violet. This discovery has indicated lack of 
sunlight during winter as one factor concerned in the large spring incidence 
of the disease in industrial cities in northern climates. 

A complete and well-controlled research showing the interaction of diet 
and light in the prevention and cure of rickets in infants was gained in 
Vienna, since the war, by Dr. Harriette Chick of the Lister Institute and 
her four colleagues. There the curious fact came to light that infants fed 
on a diet deficient in anti-rachitic vitamin developed the disease only in 
winter and not in summer, and, moreover, could be cured in winter by 
exposure to artificial forms of radiation or by administration of cod-liver 
oil without any other change in diet or management. Another set of children 
who had a sufficient supply of fat-soluble vitamins in their diet, in the form 
of cod-liver oil, escaped the disease altogether. 


Experiments ou rats have also shown that in animals fed on a rickets- 
produciug diet, rickets does not occur if the rats are exposed regularly to 
sunlight or to the rays of the mercury lamp, or other form of artificial 
ultra-violet radiation ; whereas if they are kept in the dark, rickets does 
develop. If, on the other hand, the diet is complete in all respects, includ- 
ing abundance of fat-soluble vitamins, the animals do not develop the 
disease, even if kept constantly in the dark. 

How this is brought about is not known. At one time it was thought 
that the action of the ultra-violet rays on the tissues might enable the 
animal to synthesise fat-soluble vitamins, as it does in the tissues of plants, 
but recent evidence brought forward by Miss Margaret Hume in Vienna, 
and by Goldblatt and Soames at the Lister Institute, suggests that light 
can neither create nor act as a substitute for the vitamin. It seems rather 
to act as a stimulant, enabling the animal to make full and economical use 
of its store of fat-soluble vitamins, and when the store is used up growth 
ceases in spite of the continued action of the rays. 

An important and practical point in regard to the connection between 
diet and sunlight and the formation of the anti-rachitic vitamin is the 
relation to cow's milk. Recent work carried out by Dr. Ethel Luce at 
the Lister Institute has shown that milk obtained from a cow on pasture 
in summer contains a sufficiency of the growth-promoting and anti- 
rachitic fat-soluble vitamins. In winter, on the other hand, if the cow is 
stall-fed and kept in a dark stable, the milk may become deficient in these 
respects and young animals fed on it may become rachitic. This work 
shows that the seasonal variation in quality of the cow's milk may be an 
additional factor in the seasonal incidence of infants reared upon it. It 
also disposes of the idea, very current in some quarters, that cow's milk 
possesses low and negligible anti-rachitic properties and that the anti- 
rachitic properties of cod-liver oil are specific and peculiar to that 

Enough has been said to show that rickets may be regarded as a disease 
of sunless houses combined v/ith a diet deficient in the anti-rachitic vitamin, 
and the means of prevention are sufficiently obvious, if not always easy 
and simple to carry out. 

Doubtless in the future this new knowledge in regard to the accessory 
food factors in diet will be used to a greater extent than it has been up to 
the present, in which case it is not too much to expect that the city children 
of some future generation will have better-grown bodies and stronger, 
healthier teeth than their predecessors of the pre-vitamin age. 


Tliis might be attained in a comparatively near future if only man 
could be allowed to work out his salvation in peace. Instead of this, 
great wars come and throw back the work for generations. 

To saddle the country with a million and a half of unemployed, with 
the consequent poverty, insufficient food, clothing and housing, is not 
calculated to further the prevention of disease and raise the standard of 
health. Is it too much to hope that in the revolving years a time 
may come when by a Confederation or League of Nations the world 
may be so policed that no one country will be able with impunity to attempt 
the destruction of its neighbour ? Until this happens it is difficult to see 
how rickets, tuberculosis, and other diseases can be adequately dealt with 
in our city populations. 


I can only briefly allude to the astonishing advance in our knowledge 
of the diseases caused by a defect or excess of secretion of the ductless 
glands. Many of these discoveries are among the fairy tales of science. 

All this advance has taken place in the comparatively short space of 
time under review. 

Professor Starling, one of the chief protagonists in this advance, in 
his Harveian Oration a year ago states this very vividly : ' When I 
compare our present knowledge of the workings of the body, and our powers 
of interfering with and of controlling those workings for the benefit of 
humanity, with the ignorance and despairing impotence of my student 
days, I feel that I have had the good fortune to see the sun rise on a darkened 
world, and that the life of my contemporaries has coincided not with a 
renaissance but with a new birth of man's powers over his environment 
and his destinies, unparalleled in the whole history of mankind. Not but 
there is still much to be learned : the ocean of the unknown still stretches 
far and wide in front of us, but for its exploration we have the light of day 
to guide us ; we know the directions in which we would sail, and every 
day, by the co-operation of all branches of science, our means of conveyance 
are becoming more swift and sure. Only labour is required to extend 
almost without limit our understanding of the human body and our 
control of its fate.' 

There is one point of likeness between the vitamins which we have been 
considering and these glandular secretions, or hormones, as they are named. 
Just as we have seen that the presence or absence of an extremely minute 


quantity of a vitamin may determine growth and health or disease and 
death, so an extremely minute quantity of glandular secretion may have 
a similar effect. 

The anterior lobe of the pituitary gland is a very small body, yet an 
excess of its secretion will cause a child to grow into a giant ; a deficiency, 
and the growing child will remain an infant. 

The best known of the ductless glands is the thyroid, and the effect of 
its secretion is truly marvellous. A deficiency, and the child grows up a 
heavy-featured, gibbering idiot. Rectify the supply of thyroid secretion : 
the heavy features disappear, the eyes brighten, the intelligence returns, 
and instead of the former heavy-jowled imbecile you have a bright, happy 
and normal schoolboy. 

On the other hand, if there is an excess of the thyroid hormone, 
exophthalmic goitre, or Graves's disease, is the result. Remove the 
redundancy and health returns. 

The active principle of the thyroid has lately been shown to be a com- 
pound containing iodine. If there is no iodine in the soil or water, goitre 
is the result, as in parts of Switzerland, Canada, and the United States. 
This aspect of the subject was taken up some ten years ago by Dr. David 
Marine and his colleagues at Cleveland, Ohio. They find that endemic 
goitre may be prevented by the simple method of giving for a time minute 
doses of iodine, and conclude that with this simple, rational, and cheap 
means of prevention, this human scourge, which has taken its toll in misery, 
suffering, and death throughout all ages, can and should be controlled, if 
not eliminated, and look forward in imagination, a few generations hence, 
to the final closing of the chapter on endemic goitre and cretinism in 
every civilised nation in the world. 

Many advances have also been made in our knowledge of the function 
and uses of other ductless glands, and, as you know, the latest victory 
in this field is the discovery of insulin and the successful treatment of 
severe diabetes, for which magnificent work your own townsmen Banting 
and Best deserve the highest honour. 

Inmanyotherdirections than those touched uponhas there been progress 
in the prevention of disease. It would take more than one address to 
describe the activities of the Rockefeller Foundation alone. Campaigns 
for the relief and control of hookworm disease, malaria control, the eradica- 
tion of yellow fever, anti- tuberculosis work and education are being pursued 
on such a scale and at such a lavish expenditure of money as to leave us 
in the Old Country breathless with admiration and envy. 


This foundation, incorporated in 1913, was founded, in the words of 
the President, ' to stimulate world-wide research, to aid the diffusion of 
knowledge, to encourage co-operation in medical education and public 
health.' Its chartered purpose is to promote, not the exclusive prosperity 
of any one nation, but ' the well-being of mankind throughout the world.' 

Science, indeed, knows no boundaries of nations, languages, or creeds. 
It is truly international. We are all children of one Father. The advance 
of knowledge in the causation and prevention of disease is not for the 
benefit of any one country, but for all— for the lonely African native, 
deserted by his tribe, dying in the jungle of sleeping sickness, or the Indian 
or Chinese coolie dying miserably of beri-beri, just as much as for the 
citizens of our own towns. 

From what has been said it is abundantly clear that during the com- 
paratively few years that have passed since this Association first met in 
Canada, enormous advances have been made in the prevention of disease. 
Before that time we were still in the gloom and shadow of the dark ages. 
Now we have come out into the light. Man has come into his heritage 
and seems now to possess some particle of the universal creative force 
in virtue of which he can wrest from Nature the secrets so jealously guarded 
by her and bend them to his own desire. 

But let there be no mistake, much has been done but much more re- 
mains to be done. Mankind is still groaning and travailing under a grievous 
burden and weight of pain, sickness, and disease. Interruptions are sure 
to come in the future as they have in the past in the work of removing 
the incubus, but, in spite of these, it is the duty of science to go steadily 
forward, illuminating the dark places in hope of happier times. 






Professor Sir W. H. BRAGG, K.B.E., D.Sc, F.R.S., 


In this address I propose to consider the new methods of analysing the 
structure of materials by means of X-rays, considering especially the 
stages by which they move towards their objective. It is convenient to 
recognise three such stages, of which the first comprises the simplest and 
most direct measurements and the last the most indirect and complex. 

The fundamental measurement of the method is the angle at which 
rays of a given wave-length are reflected by a set of planes within the 
crystal. The planes of a ' set ' are all exactly like one another : an imagi- 
nary observer within the crystal could not tell by any change in his sur- 
roundings that he had been moved from one plane to another. Sometimes 
there is no reflection of the first order from a set so defined, because the 
planes may be interleaved by other planes so spaced and of such strength 
as to annul the true reflection ; but this can always be allowed for. 
When the wave-length of the X-rays is known, the angular measurement 
can be used to find the spacing of the set of planes, and in this way a 
linear dimension of the crystal is measured. The spacing is the distance 
between any plane and its nearest like neighbour on either side. If the 
spacings of three different sets of planes are found, the volume of the 
unit cell is found. The crystal unit cell is bounded by six faces, each set 
of planes furnishing a pair. The pair consists of two neighbouring planes 
of the set. The cell may have a great variety of forms, but has always the 
same volume. The specific gravity of the substance being known, it is 
possible to find the number of atoms of various kinds which the cell con- 
tains : the proportion of the various kinds is necessarily the same as in 
the molecule of the substance. The cell is in practice found always to 
contain a small integral number of molecules, one, two, three, or four, rarely 
more. This assemblage of molecules is fully representative of the crystal ; 
by the mere repetition of the cell, without the addition of any new 
features, the crystal with all its properties is produced. 

There are, therefore, three types of assemblage. The simplest is that 
of the single atom, as in helium in the gaseous state, in which the behaviour 
of every atom is on the whole the same as the behaviour of any other. 
The next is that of the molecule, the smallest portion of a liquid or gas 
which has all the properties of the whole : and lastly, the crystal unit, 
the smallest portion of a crystal (really the simplest form of a solid 


substance) which has all the properties of the crystal. There are atoms of 
silicon and of oxygen : there is a molecule of silicon dioxide, and a crystal 
unit of quartz containing three molecules of silicon dioxide. The separate 
atoms of silicon and oxygen are not silicon dioxide, of course : in the same 
way the molecule of silicon dioxide is not quartz ; the crystal unit consist- 
ing of three molecules arranged in a particular way is quartz. 

The final aim of the X-ray analysis of crystals is to determine the 
arrangement of the atoms and the molecules in the crystal unit, and to 
account for the properties of the crystal in terms of that arrangement. 

The first step is the determination of the dimensions of the crystal unit 
cell : any one of the possible ways in which the cell can be drawn will do. 
When this has been completed it is a simple calculation in geometry to 
find the distance between any atom and any other atom in the crystal of 
like kind and condition, or, in other words, the distance an observer would 
have to travel from any point within the crystal to any other point from 
which the outlook would be exactly the same and would be similarly 
oriented. This is the only measurement which the X-rays make directly : 
any other measurement of distance is made indirectly, by aid of some 
additional physical or chemical reasoning. It is not possible by direct 
X-ray measurement to determine the distance between any two points — 
atom centres, for example — within the same cell. 

Let us take an example. The crystal unit of naphthalene has the 
dimensions defined in the usual way by the statement :— 

a = 8.34A 6 = 6.05A c = 8.69A [3 = 122° 49' a = Y = 90°. 

It contains two molecules : an integral number, as always. These facts 
are given directly by the X-ray measurements. But there is no direct 
determination of the distance between any carbon atom and any other 
carbon atom contained within the same cell : the measurements given 
are those of the distances between any atom and the nearest neighbours, 
in three principal directions, which are exactly like itself, these distances 
being the lengths of the edge of the cell. There is not even a measurement 
of the distance between the two molecules in the same cell, because they are 
not similarly oriented. In fact, there is no clear meaning in the term 
' distance ' in this case, just as we cannot state the distance between an 
object and its image in a mirror, unless the object isa pointof no dimensions. 
If the molecule of naphthalene has a centre of symmetry, as is indeed 
indicated during the development of the results of the X-ray analysis, it 
is possible to state the distance between the centres of symmetry of the 
two molecules in the same cell, but this does not define the distance between 
any atom in one of the two molecules and any atom in the other. All 
such distances, if they are to be defined and measured, can only be found 
by the aid of fresh considerations. 

Or again, let us take the case of rock-salt. The crystal unit cell of rock- 
salt contains one molecule : one form of the cell has for its eight corners 
the six middle points of the faces of a certain cube (edge=5.62 A.U.) and 
two of the opposite ends of any diagonal of the cube. The so-called face- 
centred cube is four times as large as the cell, and contains four molecules. 
The dimensions of the cell are determined directly by the X-rays, which 

D 2 


measure the distance between each of the three pairs of parallel faces that 
contain it. The cell may be placed so that each corner of it is associated 
in the same way with a molecule of sodium, let us say : and, of course, the 
knowledge of the dimensions of the cell is equivalent to a knowledge of the 
distance between any two sodium atoms in the crystal, which atoms are 
all alike in every respect. But we have no direct measurement by the 
X-ray methods of the distance between a sodium and a chlorine atom. 
We infer that the chlorine atom lies at the centre of the sodium cell, or vice 
versd, from considerations of symmetry. Crystallographic observations of 
the exterior form of the cell assign to the crystal the fullest symmetry that 
a crystal can possess. If the cell that has been described is to contain the 
elements of such full symmetry, the chlorine atom must lie at the centre of 
it. It cannot lie anywhere else, for every cell would contain a chlorine 
atom similarly placed. There would then be unique directions in the 
crystal; that is to say, polarities. Moreover, both the sodium and the chlorine 
atoms must themselves contain every symmetry of the highest class : 
the full tale of planes of symmetry, axes of rotation, and so on. They both 
have centres, and we can state the distance between a chlorine atom and a 
sodium atom because we can state it as between centre and centre, and put 
it equal to half the distance between two sodium atoms on either side 
of the chlorine. The structure of sodium chloride is then determined 

It may possibly be a difficulty that the cell so described does not at 
first appear to have all the symmetries of the rock-salt cube, but it is to 
be remembered that we are to expect the full display of symmetries only 
when the cell has been repeated indefinitely in all directions. We may take 
a simple case as follows : 

• O i 

Fig. 1 

Suppose sodium and chlorine atoms were to be arranged in a line as in 
the figure, just as they are in any of the three principal directions in the 
crystal. A plane of symmetry perpendicular to the line of atoms indefi- 
nitely prolonged may be drawn through the centre of any atom. The unit 
cell is one molecule : one chlorine and one sodium. The unit by itself 
has not this symmetry, but the repetition of the same molecule in either 
direction on either side provides the symmetry. Moreover, each sodium 
and each chlorine must itself have a plane of symmetry, and the planes 
are equally spaced. We can state the distance between a sodium and a 
chlorine atom as half the distance between two sodiums. 

Let us take one more instance, the diamond. The crystal unit cell 
contains two atoms of carbon: as in the case of rock-salt, it may be so chosen 
that, of its eight corners, six are the middle point of the faces of a 
certain cube and two are the ends of any diagonal of the cube. The sides 
of this cell are determined by the X-rays, and are all equal to 2.52 A.U. 
This is the distance between any carbon atom and the nearest carbon atom 
which is exactly like itself. The distance between the two carbon atoms 
in the same cell is not measured directly, but can be inferred after it has 


been defined. This we are able to do because the carbon atom is tetra- 
hedral ; a tetrahedron has a centre, and we can state the distance between 
the centres of two tetrahedra, no matter how the tetrahedra are oriented. 
We know that the carbon atom, as built into the crystal, is tetrahedral, 
because the X-ray observations show that four trigonal axes meet in it. 
The two atoms in the cell are oriented differently ; one may be said to be 
the image of the other, if translation shifts are ignored, in each of the faces 
of the cube. Considerations of symmetry or X-ray observations show 
that the centre of an atom of the one orientation lies at the centre of a 
tetrahedron formed by four atoms of the other orientation. The edge of 
this tetrahedron is the edge of the unit cell, and its length is 2.52 A.U. It 
may then be calculated that the distance between the one atom and the 
others, its nearest neighbours, is 1.54 A.U. We may call this distance the 
diameter of the carbon atom, but we must remember our original definition 
of the meaning of the term. Thus the 2.52 A.U. is the result of a direct 
unaided X-ray measurement, but the 1.54 A.U. is not, and has no meaning 
except after special definition. 

Only such distances between atoms as can be calculated from the 
dimensions of the unit cell can be measured directly and without 
qualification. The determination of these distances may be looked on as 
the result of the first stage of the analysis by X-rays. 

We now come to a second stage. It is possible to make other statements 
of the relative positions of atoms and molecules which, though less complete 
and informative than those of distances, and their orientations, are necessary 
to the solution of the crystal structure problem. These also are deduced 
by means of the X-ray methods. 

It often occurs that the atoms or molecules in one cell can be divided 
into two portions which are the reflections of one another across some 
plane, or can be brought to be the reflection of each other by a shift 
parallel to the plane. In that case the orientation of the plane and the 
amount of the shift can be stated definitely, the former by inspection of 
the crystal or by X-ray observations, the latter by X-ray observations 
alone. So also it may happen that the atoms or molecules in the same 
cell may be divided into portions which can be made to coincide with each 
other by a rotation round some axis with or without a shift parallel to that 
axis. The direction of the axis can be found by inspection of the crystal 
or by X-ray observations; the amount of the shift can be found by X-ray 
observations alone. 

In these cases the distances that are found by the X-ray method are 
all that can be stated without special definition. It is not possible to state 
the distance between an object and its image in a mirror, if the object has 
any extension in space ; but it is possible to state the magnitude of a shift. 

Measurements of this sort constitute a characteristic feature of the 
X-ray analysis, for which reason I would like to discuss them briefly. 

We know that it is possible to separate crystals into thirty-two classes, 
according to the kind of external symmetry which they display. As we 
have hitherto been unable to look into the interior of the crystal, we have 
been obliged to be content with this imperfect classification by outer 
appearance. It has been shown, however, that there is a classification by 
inner arrangement which is perfect and includes the other. It is beyond 
the limits of ordinary vision : out of the range of the lens and the 




<( m 




goniometer. The interior arrangements of the crystal, of which the outer 
form is one consequence, are so varied as to furnish 230 different modes. 
With very few exceptions the X-rays now allow us to carry the classification 
to this higher degree. If the modes are grouped according to the external 
features of the crystals that follow them, we come to the well-known 
thirty-two classes, there being several modes in every class. I may be 
permitted to illustrate this important point by examples, although it is 
familiar to those who have studied crystallography. Let us consider 
first a two-dimensional example, which is much easier to describe than 
the three-dimensional actuality, and contains all the essential ideas. 

Consider an arrangement of figures in a plane which displays symmetry 
across two planes at right angles to one another. Such arrangement may 
be exhibited diagrammatically, as in fig. 2. The unit cell may be drawn 
in various ways, EFKJ, EFLK, RSUT, and so on. The cell contains, 
however it is drawn, either a whole diamond or enough parts to make up a 
whole diamond. Bach diamond can be divided into four parts : B and D 
are the reflections of A and C across a plane ; C and D are the reflection of 
A and B across a plane at right angles to the first plane. Unless the dia- 
mond, the content of one cell, could be divided in this way there could not 
be the double symmetry. But, granted this division into four portions, 
it is not necessary that the four should be arranged as in the figure in order 
that the double symmetry may be obtained. There are two alternatives 
(figs. 3 and 4). 

In fig. 3 the lower half of each diamond — that is to say, the portions C and 
D — are shifted, whether to right or to left is immaterial, by an amount equal 
to one-half of one side of the cell EFKJ. The symmetry about a vertical 
line in the plane of the paper is obviously retained. It is not so obvious 
that there is still any symmetry about the horizontal line until we realise 
that we mean only ' observable symmetry ' : that which is to be seen in the 
outer form of the indefinitely extended figure, corresponding to the crystal. 
Clearly, the whole figure will present the same appearance from below as 
from above. In fact, we can see that as a whole the lower part of the 
figure is symmetrical with the upper part by imagining the upper and the 
lower to be further shifted relatively as in fig. 3a: the two parts sliding on 
one another along the line SS. The two parts are then the image of 
each other across SS in the full sense of the word. 

From fig. 2 we may also realise that the amount of the original shift 
must be equal to one-half of EF : no other shift will give the symmetry 
which fig. 3a shows. In figs. 5 and 5a a different shift has been given, and 
the failure is clear. 

In fig. 4 not only are C and D shifted parallel to the horizontal line, 
but also B and D are shifted parallel to the vertical ; this time the amount 
of shift is one-half of the side EJ. 

The three modes of figs. 2, 3 and 4 all lead to the same external sym- 
metry. There is one more which is based, as we should say, on a different 
lattice and is symmetrical, like the others, about two lines at right angles 
to each other. It is shown in fig. 6. There are no variations of fig. 6, as of 
fig. 2, to be obtained by the introduction of shifts. If in fig. 6 we shift 
C and D relatively to A and B, as we did in fig. 3a, we find that they 
can now be described as the direct reflection of A'B' into CD and of 
A'C into B'D, and the mode of fig. 6a is the same as that of fig. 6. 






There are therefore four modes in one class : four varieties of internal 
arrangement which all lead to the same external appearance of symmetry. 

Our example is two-dimensional, and the crystal has three dimensions. 
But there are no new ideas to be added : it is only the numbers of sym- 
metries, modes, and classes that are increased. If, for example, we continue 
the study of the modes of arrangement that lead to an external symmetry 
of reflection across two planes at right angles to each other, we find that 
there are four lattices instead of two, and twenty-two modes instead of 
four. The class containing crystals that possesses this particular form of 
symmetry is generally called the ' hemimorphic class in the orthorhombic 
system.' Its symbol is C,, : the symbols of the four lattices are 
Tj To' r„" To"'. In everycase the content of the unit cell is divisible 
into four parts, corresponding to the ABCD of figs. 2 to 6. The ten 
modes in the T, lattice are shown in fig. 7, which will serve to show the 
numerical increase due to the introduction of the third dimension. Under 
each separate figure is given, beside the crystaUographic symbol, another 
symbol which describes the shifts : D^ means a direct reflection across a 
plane parallel to yz ; E^ a reflection across a plane parallel to yz, 
together with a shift parallel to the axis of y equal to half the y edge of 
the cell, and M'' a reflection across a plane parallel to yz, together with a 
shift parallel to the diagonal of the yz face and equal to half that 

Let us now see how the X-ray analysis distinguishes the mode. Let 
us imagine that fig. 2 represented a number of pits in a plane reflecting 
surface. The surface could be used as a grating having many spacings 
instead of one. If, for example, we so placed it that the horizontal Imes 
of the figure were parallel to the slit of the spectroscope the spacing would 
be equal to EJ : if the vertical, the spacing would be equal to EF. Again, 
if the grating were so placed that EK, for example, were vertical, the spacmg 
would be the perpendicular distance between EK and FL. If the surface 
is pitted as in fig. 3, the spacing when the horizontal line is parallel to 
the slit is the same as before ; but when the vertical is parallel to the slit 
the effective spacing is only half what it was in fig. 2. This follows from 
the fact that if we divided the surface into a number of vertical narrow 
strips the diffracting effect of each such strip, for this position, depends on 
the total amount of reflecting surface contained in the strip, but not on its 
distribution along the slip. It does not matter that C and D are upside- 
down as compared to A and B. The strata consisting of C and D portions 
have interleaved the strata of A and B portions. This halving of a spacing 
of fig. 3 as compared with fig. 2 occurs only when the grating is placed 
so that the slit is parallel to the vertical line of fig. 3, and not when any 
other line is vertical, except by some odd chance connected with the shape of 
the pits. In this way it is possible to distinguish between fig. 2 and fig. 3. 
The mode shown in fig. 4 is distinguished by the halvings of both the hori- 
zontal and vertical spacings, and of no others. In the case of fig. 6, as 
compared with fig. 1, the spacing is halved when the slit is parallel to the 
horizontal or the vertical line of the figure, and also whenever the grating 
is so placed that the parallel to the slit passing through one of the corners 
of a cell does not pass through the centre of that or any other cell, as, for 
example, if EO but not EK is parallel to the slit. It is therefore easy to 
distinguish each of the four modes. 



Similar methods are applicable to the three-dimensional crystal. If, 
for example, we consider the case of C|, or D^E^ we can show that, whereas 
in general the spacings of planes are such as are proper to a cell of the dimen- 
sions and form drawn in the figure, all planes of the form lxja-\-mzjc=an 
integer, show halved spacings, unless I is odd and m is even : which is 
sufficient identification of the mode of arrangement. The symbols a and 
c denote edges of the cell. 

If we follow this line of reasoning through all the thirty-two classes, 
we end, of course, with the discovery of the 230 modes which are known to 
exist : and with the identification marks of each, with certain qualifica- 
tions. These last are of two kinds. One of them is general in nature and 
is a consequence of the fact that the X-rays can measure only the distance 
between two like points in neighbouring cells, say A and B. But they do 




Pig. 8. 

not indicate any difference that may exist between AB and BA. If such 
a difference exists it may be expected to show in the external characteristics 
of the cell, giving it polarity. A good example is to be found in zinc blende. 
Layers of zinc and of sulphur atoms alternate with one another as in fig. 9, 
all of them being perpendicular to a trigonal axis of the crystal. The 
distance between a zinc atom in the layer A to a zinc atom in the layer B 
is found without question by the X-ray method. Now we know from 
observation of the crystal that there is a difference between AB and BA : the 
crystal is polar. A crystal plate cut so that its faces are perpendicular to 
the axis shows different properties on its two sides : if heated, one face 
becomes positively and one negatively electrified. Whichever face we use 
in the X-ray spectrometer we obtain the same value for the spacing, and 
we find ourselves unable to detect any difference between the two aspects 
by means of the spectrometer observations. 

We may see this point in another way. Suppose that fig. 9 
represents a section of a crystal consisting of two kinds of atoms, indicated 
respectively by full and empty circles. The arrangement clearly has no 
symmetry about a vertical line in the plane of the paper. But if X-rays 
were incident from above, as shown there would be equal reflections from 
the planes 11' and 22'. If the incident rays were heterogeneous and a 
photographic plate were placed to receive the Laue reflections in the usual 
way, there would be a symmetry distribution of spots on either side of A, 
although there is no symmetry in the crystal to correspond. 

It is only when we have taken other considerations into account and 
have determined the structure that we can establish the polarity of the 
crystal. We may take, for example, the fact that zinc blende is cubic, 
and therefore has four trigonal axes, a fact which we may discover from 
X-rays as well as from the external form. Also, the unit cell contains only 
one molecule of zinc sulphide, and may be drawn of the same form as in 
diamond : that is to say, its eight corners can consist of the six centres 



of cube faces and the two ends of a diagonal. If we put zinc atoms at 
the corners of the unit cell, the sulphur atom must lie either at the centre 
of the unit cell or at the centre of the regular tetrahedron formed by four 
of the corners of the cell : only by the adoption of one of these alternatives 
do we get the four trigonal axes. The former gives the rock-salt structure 
and is distinguished by the fact that the (100) and (110) spectra decrease 
regularly in intensity from lower to higher orders, whereas in the (111) 
spectrum the even orders are relatively greater than the odd. In the latter 

alternative the even orders of (100) are relatively greater than the odd, 
(110) spectra are normal, and the second order of the (111) is abnormally 
small. It is easy to distinguish between the two cases. The latter is 
adopted by zinc blende. Each atom has the symmetry of Class 31, to 
which the crystal belongs, there being only one atom of each in the 
unit cell. 

In this case we are successful from X-ray measurements alone in deter- 
mining the mode of arrangement of the crystal, although the crystal is 
polar and the X-rays cannot detect polarity directly. We have been able 
to determine the structure completely, and the polarity then appears. 


When the determination of structure cannot be carried far enough, 
the X-rays may fail to decide between the presence and absence of polarity. 
For example, resorcinol is an orthorhombic heraihedral crystal : this is 
known by its external form. The X-rays show that, this being so, its 
internal arrangement must be that of M'^M" or C'° in fig. 7. If we 
had no help from the study of external form, or from any other source, 
we should not be able to decide between Q° and the more symmetrical 
mode known as Ql^ : the symmetry of the latter is obtained by adding a 
centre of symmetry to the elements of symmetry possessed by CJJ : 
that is to say, by removing the polarity of the crystal. As a matter of fact, 
the external form of resorcinol clearly shows polarity : or, if we could be 
sure that the molecule had no symmetry, we could infer that the crystal 
was unsymmetrical about the xy plane, there being only four molecules 
in the cell and all these being wanted to give the symmetry observed by 
X-rays. Thus there are cases where the X-rays cannot decide between 
two modes, one of which can be derived from the other by the addition of 
a centre of symmetry. As, however, the existence of a centre of symmetry 
can generally be decided by other means — for example, by such means as 
I have described above in the case of zinc blende or of resorcinol — this 
incapacity of the X-ray method is of no great consequence. 

The addition of a centre of symmetry moves a structure from one class 
to another— Class 1 to Class 2, Class 31 to Class 32. Consequently, the 
X-ray methods are by themselves sometimes in doubt between two modes 
in different classes when they are rarely in doubt as to the mode within a 
class. It will readily be understood that the doubt as to class may be of 
far less importance than the doubt as to mode ; though hitherto the former 
kind of difference has been given all the attention because it has been the 
only kind that could be observed. A very slight relative movement of 
the atoms would be sufficient to reduce the symmetry of the crystal from 
one class to another : but the change from one mode to another within 
the same class would mean a complete rearrangement of the molecules. 
There are two cases in which the X-rays cannot distinguish between 
two modes in the same class. These are Q» and Q^ in the enantiomorphous 
class of the orthorhombic system, and T" and T' in the tetartohedral class 
of the cubic system. The ambiguity disappears, however, if there are only 
two molecules in the unit cell, when the former alternative is alone per- 
missible in each case : it would disappear also in any case in which the 
structure could be determined completely by any other means. 

It has been known for many years, thanks to the work of Fedorow, 
Schonflies and Barlow, that the 230 modes of arrangement represent all 
the possible forms of internal crystal structure. In each mode of arrange- 
ment there is a relative disposition of planes, axes and centre of symmetry, 
which is characteristic of the mode, and the mode may be described in terras 
of these symmetries. This was the language used in the original work on 
the subject, and the term ' space group ' was used, instead of the term ' mode 
of arrangement,' in reference to the particular group of symmetry planes, 
axes and centre in space. When the subject is approached from the point 
of view of the X-ray worker, the language of the mode of arrangement has 
its special conveniences. A list of the 230 modes, and of the X-ray tests 
for each mode, has recently been published in the Transactions of the 
Royal Society by Astbury and Yardley. Lists of the same 230 space 


groups have already been published in difierent terms by writers on 
crystallography : recently a list by WyckofE has been published by the 
Carnegie Institution of Washington, in which each space group is expressed 
in terms of the co-ordinates of the arrangement of points required to 
give each space group its special characteristics. 

It may be of interest to look at these matters from a somewhat difierent 
point of view, which takes in the question of the permanence of the 
chemist's molecule when built into the solid structure. 

In every crystal the unit can be divided into a certain number of parts, 
each of which has no symmetry of its own, but may be made to coincide 
with any other part by some combination of reflections, rotations and shifts. 
The number is always either one, two, three, four, six, eight, twelve, 
twenty-four, or forty-eight. The division into 230 modes of arrangement 
refers to the arrangements of these parts. In the case of a crystal of the 
rock-salt t3rpe both the positive and negative portions of the cell can be so 
divided. Very often the part in question is the chemical molecule. For 
example, the cell of the monoclinic prismatic class can be divided into four 
such parts. The X-ray measurements show that the unit cell of benzoic 
acid which belongs to this class contains four molecules. Also they 
detect the existence of the four parts, and determine the mode of their 
arrangement. It is natural to make the assumption that each part is a 
molecule. This, it may be noted, involves the existence of right- and left- 
handed molecules, as built into the crystal. 

Sometimes the division into parts involves the division of the molecule. 
The molecule then consists of two or three or more parts, and therefore 
possesses a corresponding symmetry. For example, the naphthalene 
molecule in the naphthalene crystal contains two parts, and has a centre 
of symmetry. The molecule of FeS^ in the crystal of iron pyrites consists 
of six parts, and has a centre of symmetry and a trigonal axis. Each of the 
two atoms in the rock-salt cell, sodium and chlorine, has — that is to say, its 
relations to its neighbours have — forty-eight parts, and therefore the full 
symmetry of the crystal. 

Much more rarely a part consists of more than one chemical molecule. 
So far a few instances have been met with. The ' part ' in the crystal 
cell of sulphur certainly contains two, perhaps more, atoms. Miss Yardley 
finds that the ' part ' in the fumaric acid crystal contains three, perhaps 
six, of the molecules as ordinarily defined (COOH.CH : ).^. In the cell of 
a-naphthylamin at least three molecules go to a part. The part has no 
symmetry, so that the molecules that compose it differ from each other in 
some way. These are really examples of polymerisation in the crystal. 

Is the grouping of the atoms in the molecule as displayed in chemical 
reactions maintained without change ? When the first results of the new 
methods were published, with their determinations of diamond and rock-salt 
structure, there was some unnecessary alarm as to the apparent disappear- 
ance of the molecule. If there had been anything to suggest a complete 
disruption of all the alliances in the molecule, which had been so long and 
so successfully studied by the chemists, the alarm would have been 
justified. Atomic bonds would have been annoyingly variable and depen- 
dent on conditions, and we should have been put back to the starting- 
point in the investigation of the solid. This condition of things appears, 
fortunately, to have no existence. The conclusions of chemistry are carried 


into the solid, with onlysuch modifications as might reasonably be expected. 
Our new science is in full and close alliance with chemical science already 
established : it is in fact a constant and delightful experience to find some 
direct confirmation or illustration of an inference already drawn from other 
sources. So far as experience has to tell us, the chemical molecule generally 
takes its place as such in the crystal structure with little change. 

To sum up, we are now able to replace the rough division into thirty-two 
by the finer division into 230. This is advancing a whole stage towards 
the final solution of the structure problem. We carry the analysis right 
up to the limits which can be foreseen by the mathematical investigation 
of the geometry of space. We require only a sufiicient number of X-ray 
measurements : if these can be obtained, the crystal then — with certain 
additional information as to polarity — can be assigned to its particular 
mode or space group, with one or two exceptions as already noted. It may 
be that the structure of the crystal is so simple that having got so far the 
full solution is already in sight. In the vast majority of cases this is not 
so - we have only come to the end of the second stage of the work. 

The first stage was complete when we had found the dimensions of the 
crystal unit cell : the second is completed when we know which of the 230 
possible arrangements of molecules, or, in other words, space groups, the 
crystal structure follows. 

If the structure of the crystal is not yet obvious — and in the great majo- 
rity of cases this is far from being the case — we enter on a third stage, in 
which the mode of procedure is less stereotyped and more difficult, perhaps 
all the more interesting. We have now to find, if we can, the arrangement 
of the atoms within the cell, to which task the knowledge already gained is 
an indispensable though, it may be, a quite insufficient contribution. 

As I have said already, the X-rays do not tell us directly the relative 
positions of the atoms within the unit cell. They have, however, much to 
tell us as to the relative intensities of the different orders of reflection 
by each plane, and these must depend on the atomic arrangements. It is 
to be admitted, however, that we are as yet unskilled in the interpretation 
of this evidence. We do not completely understand how varying conditions 
affect intensities of reflection, though we have learnt a great deal through 
the work of W. L. Bragg, Darwin, Compton, and others. And, of course, 
when the cell contains many molecules, their positions being as yet unknown 
and their separate contributions to the intensities in any case doubtful, 
the observations of intensity are very difficult to make use of, though they 
can be accurately measured. We can only avail ourselves of such bold 
indications as that a very strong reflection implies the location of many 
atom centres on or near the plane in question, particularly if there are 
higher orders : or we may find ourselves able to show that an especially 
strong second or third or other order implies the adoption of some particular 
alternative arrangement. A very interesting example of a general 
influence of form upon intensity is to be found in the reflections from the 
fatty acid layers which have been investigated by Muller and Shearer. 
The first, third and other odd orders are much more intense than the second, 
fourth and other even orders. A simple explanation is found in the fact 
that these long chains face opposite ways alternately, and that the number 
of scattering centres is distributed fairly evenly along their length. At the 
ends, however, the uniformity of distribution is interrupted ; at one end> 


probably the carboxyl end, there is an excess per unit length ; at the other, 
the methyl end, a deficiency. Thus we may say that the effect on an odd 
order of the spectrum due to a single layer, the thickness of a layer being 
twice the length of a molecule, contains a factor : — 

A sin(w< — a) — B sin(co« — a — 2n + l7r) = (A+B) sin(6>< — a). 
The factor for an even order is : — 

(A — B) sin((o; — a). 

If at both ends there had been an excess of scattering centres, we should 
have found the even orders stronger than the odd : the effect we find, for 
example, in the (111) planes of rock-salt. In the case of the simpler inorganic 
crystals like rock-salt, diamond, and so on, intensity observations are con- 
clusive as to the structure : in the case of iron pyrites or calcite they are 
very nearly so. But in the case of quartz, where the cell contains nine 
atoms, still more in the case of an organic compound, they do not carry 
us very far. We hope that greater experience will give us in the future 
the power of using them to better advantage. 

In what other direction then shall we look for additional means of 
approaching more nearly to the final solution of the problem of structure ? 

The answer to this question will take account of all the store of physical 
and chemical knowledge which we already possess. Having solved, 
wholly or in great part, the structure of some of the simpler crystals, and 
being able to proceed in all cases, even of the most complicated crystals, 
to the determination of the number of molecules in the cell, and of their 
mode of arrangement, we must try to correlate what we have found with 
the properties of the crystal. By that means we shall become gradually 
more certain of the general connection between the structure and its 
physical and chemical properties ; we shall become able to settle further 
structural details in various cases, and so, by alternate and mutually 
supporting advances, we may hope to reach our goal. 

Let us consider what is being done in this direction. First of all there 
is the question of the distribution of the atoms in space. Given so many 
atoms, to be packed into a cell of known dimensions, what information 
have we as to the space that each must occupy ? The answer to the ques- 
tion cannot be simple, because we may not expect that the atoms are 
always to be treated as spheres, still less as spheres of constant radius. 
It is as generally difficult to state the distance between one atom and 
another as to state the distance between a table and a chair. Nevertheless, 
the atom-radius is a useful conception, especially when its dependence 
on the nature of combination is taken into account. The question has 
been considered by W. L. Bragg, Wyckoff, Davey, and others, and it 
appears that an atom does make a definite contribution to the distance 
between its centre — when it can be assumed to have a centre — and the 
centre of a neighbour, so long as the nature of the bond remains the same. 
This is a valuable contribution to the study of structure. It is proved by 
the examination of simple structures like those of the alkahne hahdes, 
and we may assume its reliability in our attempt on more complicated 
problems. And, of course, it is interesting from the point of view of atomic 
structure itself, and atomic linkages. 

The radius seems to depend on the tightness of the bond as in bismuth 


or in graphite, where there are two kinds of bonding, and the plane of 
cleavage cuts across all the longer distances from centre to centre. In 
calcium fluoride the centres of calcium atoms are closer together than they 
are in the metal itself in spite of the interposition of the fluorine atoms ; 
and in calcium oxide they a'-e still closer. The change in the type of the 
bonding has altered the value of the radius. 

There is 3,lso the very interesting but still more unsettled question of 
the mutual orientation of the bonds between an atom and its neighbours. 
It is, of course, the carbon atom which is the occasion of this problem in 
its most pressing form. In the diamond the exactly tetrahedral arrange- 
ment of bonds is associated with great rigidity, which implies great stiffness 
of orientation. The analysis of the structure of graphite has lately been 
carried by Bernal to a stage very near completion, but the only point 
in any doubt is unfortunately the very one as to which certainty would be 
welcome. Has the great weakening of one bond interfered with the relative 
orientation of the other three ? Debye thought that the structure was 
trigonal, and that the atoms were arranged in layers which were like the 
layers of diamond, except that they were flattened out without a sideways 
extension of the network. This would involve a closer approach of carbon 
atom centres from 1.54 A.U. to 1.45 A.U. ; against which no obvious objec- 
tion can be offered, but it would be interesting to know how it happened. 
Hull believed the structure to be hexagonal, and that the layers remained 
as in the diamond. Bernal, having found some good graphite crystals 
to which the single crystal methods could be applied, finds that Hull is 
correct as to the hexagonal structure, but inclines to the belief that the 
layer is flattened. In the latter case, we must suppose that the carbon 
atom has three very strong bonds almost coplanar with the carbon, and 
one weak bond at right angles to this plane. 

The question arises in another form in the investigations of the long 
carbon chains by Piper and others, and especially by Muller and Shearer. 
If the chains are formed by the linking of carbon atoms together in such a 
way that the junctions of one atom to its two carbon neighbours are inclined 
to one another at the tetrahedral angle of 109°28', as in diamond, then there 
are three possible forms of chain. In one of them, each two carbon atoms 
imply an increase of 2.00 A.U. in the length of the chain, and, in a second, 
an increase of 2.44 A.U. In these two cases the carbon atoms of a chain 
can lie in a plane. With one exception, all the cases examined show one or 
other of these two rates of increase. The third form of chain is a spiral, 
for which the growth of each single atom added is 1.12. In one case this 
rate of increase is found to hold : it is that in which the chain contains a 
benzene ring. This agreement between calculation and experiment shows 
with some force that the relative orientation of the bonds is maintained. 
Even when two or four hydrogens are stripped from the chain at various 
points, so as to leave a double or triple bond between consecutive carbon 
atoms, to adopt the ordinary chemical language and theory, no measurable 
change is found in the length of the chain. This does not mean that there 
is no change in the distance between neighbours : such a change would be 
small and might escape detection. But it does mean that there is no great 
change in the general straightness of the chain, such as might be expected 
from any large change in the mutual orientation of the bonds between the 
carbon atom and its neighbours. 

1924 E 


In calcite tlie three oxygens wliich surround a carbon atom must lie 
in one plane. It is supposed, however, that in this case the bonds are 
electrostatic : the carbon atom has lost its four valency electrons, and with 
them its powers of tetrahedral orientation. 

Now if we can discover the extent to which an orientation is maintained 
under different conditions we are provided with one more guiding principle 
in our attempt to discover the structure of the crystal which contains carbon 
atoms. And, of course, the organic compounds centre round the carbon 
atom and its tetrahedral structure. 

The question of orientation in respect to other atoms is more obscure, 
but it is clearly one of importance. There must be some reason why ice 
has such an open structure, and here the oxygen atom is largely concerned. 
In the ruby the oxygen atom has no plane of symmetry in relation to its 
neighbours. In organic substances the great emptiness of the structure 
implies that atoms are attached to one another at points which have definite 
positions on the surfaces of the atoms and are limited in number. And, 
generally speaking, the consideration of organic crystal structure is against 
any idea that atoms and molecules are to be treated as spheres surrounded 
by uniform fields of electric force, except in certain cases where by loss or 
gain of electrons an atom has been reduced to the outer form of one of the 
rare gases. They must have highly irregular fields, having forms which 
more or less resist any change. The weak bonds which hold molecule to 
molecule in the organic substance are not due to electron sharing as in 
diamond, or to ionisation as in rock-salt, but to an intermingling of stray 
fields belonging to definite positions on the surfaces of the molecules. 

Our attempt to discover the effect of orientation is part of a general 
attempt to discover the field of force of the atom, which is naturally a very 
difficult matter. But if we can learn only a few rules, even empirical 
rules, we are^o much the further on our way. 

Yet another obvious and most important source from which help may 
be obtained is to be found in chemistry itself. Although the chemist 
has had no means until now of measuring distances and angles, he has 
been able to build up a wonderful edifice of position chemistry. An atom 
A of a molecule is certainly linked, it may be to B, and not to C ; or again, 
of a number of atoms of the same nature and contained in the same mole- 
cule, so many must be alike, and so many may be different. 

The chemist has, for example, come to the conclusion that the naphtha- 
lene molecule is a double benzene ring, and the anthracene a triple benzene 
ring. The X-ray observations show that one of the sides of the unit cell 
of the latter crystal is longer by 2.5 A.U. than the corresponding side of 
the other, all other dimensions of the two cells being very nearly the same. 
The width of the hexagonal ring in the diamond is 2.5 A.U., so that on the 
one hand the chemical evidence suggests that the length of the molecule is 
parallel to that edge of the two cells which shows differing values, and on 
the other the X-ray conclusions give material support to the chemical view. 
Let us take another example from basic beryUium acetate, Be40(C2H302)6. 
The substance is remarkable for the ease with which it sublimes into 
a vapour consisting of whole molecules, from which we may infer 
that the molecule does not suffer much change in the process. The 
relative positions and mutual alliances of the atoms are nearly the same 
when the molecule is free as when it is built into the solid. From the 


X-ray evidence we learn that the molecule has four intersecting trigonal 
axes. We must place the unique oxygen at the centre of a regular tetra- 
hedron, and the four beryllium atoms at its corners. Each of the six 
acetate groups must be associated with one of the tetrahedron edges, and 
in such a way that the four trigonal axes are maintained. This necessitates, 
as crystallographic theory shows, the existence of a dyad axis through the 
middle points of each pair of opposite edges of the tetrahedron. The 
CjH^O.j groups must be added so as not to interfere with the existence 
of these axes. If they are placed correctly for the trigonal axes, each of 
them has a dyad axis of the kind mentioned. All this agrees with the 
chemical evidence as partly stated in the formula, which implies : — 

1. That there is one oxygen differently situated to the rest. 

2. That the four beryllium atoms are all alike. 

3. That the acetate groups are all alike. 

Further, chemists would say that the carbon atoms are not alike ; in that 
case, they must both lie on the dyad axis, since if they did not they would 
necessarily be symmetrically placed with respect to that axis and would 
be equivalent. On the other hand, the oxygen atoms in the acetate group 
cannot lie on the axis if, as is probable, they are equivalent to one another. 
They must be placed symmetrically with respect to the dyad axis. As to 
the hydrogens, we must assume either that they do not count, which is 
not at all unlikely, or that they are not all alike. It is impossible to place 
eighteen hydrogen atoms so that the group has four intersecting trigonal 
axes and that every hydrogen is like every other. The molecule has no 
plane of symmetry, the fault lying with the oxygens. It could not be due 
to the hydrogens because there are marked difierences in the intensities 
of reflection of pairs of planes, which differences would not exist if there 
were planes of symmetry, and would be small if due to dissymmetry in the 
positions of hydrogens only. It is by reasoning along such lines as these 
that X-ray evidence and chemical evidence can help each other. Many 
other instances might be given ; indeed, no complex crystal can be studied 
with success without calling in the assistance of chemical arguments. 

A fourth example of the connection between arrangement and properties 
is to be found in the recent work by W. L. Bragg on the indices of refraction 
of crystals. It has been found possible to calculate the indices of refraction 
of calcite, given the dielectric capacities of calcium, carbon and oxygen 
atoms separately. The difference between the two principal refraction 
indices is almost entirely due to a difference between the dielectric capacities 
of a set of three oxygen atoms, at equal distances from one another, when 
placed : — 

1. So that the plane in which they lie contains the direction of the 


2. So that this plane is perpendicular to the field. 

If we are able to calculate the refractive indices on these data, then it must 
be possible to find conditions governing the arrangement of the atoms, 
when we know the composition of the crystal and its refractive indices. 
For instance, the near equality of the refractive indices of potassium 
sulphate implies that the dielectric capacity of the SOj group is much the 
same in all directions, and this is in agreement with the hypothesis that the 

s 2 


oxygen atoms are grouped in some sort of tetrahedral fashion about the 
sulphur atom. 

There are still other connections between structure and properties 
which we begin to understand, and can use in proportion to our under- 
standing. The cleavage plane, and the occurrence of certain faces in 
preference to others are connected with the nature of the bonds and the 
size of the spacings. We are not surprised to find that in bismuth, or 
graphite or naphthalene, the cleavage plane cuts across the ties which we 
should expect to be the weakest of those that bind the molecules together ; 
or again, that natural faces follow the planes that are richest in atoms 
or molecules and may be assumed to contain relatively large numbers of 
linkages. In naphthalene the cleavage plane passes between the ends of 
the molecules, where the ^ hydrogens are, and where there is a deficiency 
in the number of scattering centres, as the X-rays indicate by the strengths 
of several orders of the (001) reflection. The other faces found on the 
crystal cut across the ties at the positions of the a hydrogens. 

There are many other connections between the structure and other 
properties of a substance, such as dielectric capacity, rigidity, and compres- 
sibility, conductivity both thermal and electric, magnetic constants. In 
fact, the only properties of solid bodies which are not directly and obviously 
related to crystal structure are those, few in number, that depend on atomic 
characteristics alone, such as weight ; and the absorption coefficients for 
a, p, Y and X rays, all the rays which involve high quantum energies. 
With few exceptions every aspect of the behaviour of a solid substance 
depends on the mode of arrangement of its atoms and molecules. We 
have, therefore, an immense field of research before us, into which the X-ray 
methods have provided an unexpected and welcome entrance. 

They tell us directly, as I have said, the number of molecules in the 
crystal unit cell, and the mode of their arrangement with such determina- 
tion of lengths and angles as are required to define the mode of arrange- 
ment in full. They leave us then to ally our new knowledge to all that we 
possess already as to the physical and chemical properties of substances. 
By this comparison we hope in the end to determine the position of every 
atom, and explain its influence through its nature and position upon the 
properties of the substance. It is the chemistry of the solid that comes into 
view, richer in its variety even than the chemistry we have studied for the 
past century, and possessing an importance which is obvious to us all. 
Every side of scientific activity takes part in this advance, for all sciences 
are concerned with the behaviour of matter. 








Introduction . . . . . . • ' • • • .53 

Defence : — 

Explosives .....•■••• 54 

Chemical Warfare ........ 59 

Metallurgy ......••••• 60 

Eevenue ......••••• 64 

Health 69 

Agriculture .......•••• 73 

Other Activities ........•• 78 

Organised Applied Research ........ 78 

Assisted General Research ........ 81 

Summary — before, during, and after the war 82 


It should be premised that in this account of the relationship of the State 
to chemistry in Great Britain, an attempt has been made to limit it to 
a description of the more or less direct assistance given by that science to 
various departments as they came into being or took form. Only in 
recent years, and as a result of the war, has there been a direct recognition 
of a corresponding obligation on the other side. 

It is obvious that it is to the universities, and, as was the case to a 
greater extent in the past, to private workers, that the great advances 
made by British chemists are due. Departmental requirements have, of 
course, reaped the advantage of these advances, but examples of important 
contributions to chemical knowledge emanating from the departments 
themselves are not lacking. The collected story of their connection with 
the activities of the State may be worth reciting, if it should show tlie 
development of its appeal to chemistry, and illustrate the gradual break- 
down of the view held by the chief of "the tribunal before which Lavoisier 
came, that ' the State has no need for chemists.' 

We will find that theii- employment in an official capacity was in the first 
instance in connection with the State's pressing necessities, such as its 
defence, the regulation of its currency, and the collection of its revenue, all 
of them subjects warranting the maintenance of equipment and staff. 

As the need for safeguarding the nation's health, well-being, and the 
quality of its food supply became recognised, legislation followed, frequently 


based on the work of Commissions on which sat distinguished chemists 
of the day, and it became necessary to set up a State chemical department 
to assist in carrying this into effect. 

For some time the science of chemistry had received a limited and 
vicarious assistance from State grants to the late Science and Art Depart- 
ment and to the universities, but it was reserved for the war to establish 
definitely and finally the position that the whole future existence of a 
State might and probably would depend on the existence of a flourishing 
and eflficient chemical industry. This resulted in the definite steps of 
assisting the application of science to industry, and providing direct 
encouragement for workers in the purely academic field. 

It is proposed, therefore, to sketch the development of the main chemi- 
cal activities of the State, and to review the conditions in Great Britain 
in the hope that it may be of use generally to define the present position, 
and perhaps of interest to this Dominion in the present stage of its chemical 

Defence. — ^Explosives. 

It would appear that the importation of the technical process from 
abroad is no new thing, for it is stated that in 1314 gunpowder and guns 
were being imported into England from Ghent. Not only the material 
but the executant also appears to have been imported in the person of a 
John Crab, a Fleming, who took service with the English and supervised 
the guns and munitions used at Crecy. By 1338, cannon were mounted 
on board English ships of war, and in 1346 gunpowder was being supplied 
to the King. Although the manufacture of gunpowder is mainly a 
mechanical operation, variations in the composition which must have 
involved chemical experiment are recorded in such works as the ' Fire 
Work Books ' of that interesting class, the Master Gunners. In England, 
a Master of the Ordnance in 1447 is stated to have made 20 tons of gun- 
powder. This manufacture, however, early became stabilised, and the 
proportions of the composition underwent little change until the middle 
of the nineteenth century, when it was modified, but as freedom from 
smoke began to be demanded a new propellent of a type that could be 
produced only by chemists was evolved. 

It is of interest that Faraday was employed by the War Office as Lecturer 
at the Royal Military Academy from 1829 to 1853, and on appointment 
took as his assistant James Marsh, whose name, associated with the process 
for determining arsenic, is so well known to chemists. Marsh received the 
gold medal of the Society of Arts for this work, and a silver medal from the 
Board of Ordnance for his discovery of the quill percussion tube for cannon, 
and further he devised some of the earlier types of time-fuse. Abel suc- 
ceeded Faraday at the Academy and began his long career of activity as 
scientific adviser to the War Office, becoming War Department Chemist 
in 1854. 

It is necessary to mention some of the important advances made by 
Abel and his staff, including Kellner and Deering. By pulping guncotton, 
he rendered it safe to handle and store ; his researches on the properties 
of guncotton laid the foundation of later work on its stability and explosive 
properties ; and his research (with Noble) on the behaviour of gunpowder 
when fired is an example of a thorough investigation. Abel was consulted 


also on subjects other than explosives, and in his laboratory were conducted 
experiments which led to the adoption in 1879 of the present close-test appa- 
ratus for testing the inflammability of oils, experiments on steels and the 
effect of foreign materials in them, experiments on dangerous dusts and 
on the cause of accidents in coal mines. 

The work of Abel in rescuing nitrocellulose from the position of an 
erratic substance, liable to decompose and explode on storage, led to its 
use as a reliable explosive, not only for military purposes, but also in 
commercial compositions, such as sporting powders and blasting explosives. 

When it became necessary to devise a smokeless propellent for the 
British Service, the chemical work was in the hands of Abel with his 
assistant Kellner, Dewar, and Dupre, and in 1890 this resulted in the 
recommendation for the adoption of cordite. 

It now became necessary to extend the only chemical manufacture 
carried on at the Eoyal Gunpowder Factory, that of guncotton, by adding 
the manufacture of nitroglycerine, the technical handling of cordite, and 
plant for treating acids, and accordingly in 1891 a chemical manager of 
this section with a staS of chemists was appointed. 

The chemical work carried out by the British Government for defence, 
both as to its immediate object and as to its reaction on the explosives 
industry of the country, is worth review. In such a review the position 
before the war may first be described. Propellent manufacture was 
seriously undertaken, the small quantity of high explosive used at this 
time being mostly obtained from private manufacturers. Guncotton, 
as has been stated, had been manufactured by Abel in a fairly stable form, 
and this explosive was chosen for the Service propellent cordite, together 
with nitroglycerine and mineral jelly, the mixture being gelatinised by 
acetone, so that in a plastic condition it might be squirted into the cords 
which give it its name. A close study was devoted to this manufacture in 
all its aspects ; the processes of manufacture were greatl}' improved, and 
the dangers reduced. 

The Royal Gunpowder Factory took its place as a model of an explosives 
factory, and afforded an example of what could be done by a State depart- 
ment in conducting a scientific manufacture with regard to improved 
technique, economy, and efficiency. Thus the method of nitration to 
produce guncotton was greatly improved in safety, freedom from fumes, 
and ultimate stability of the product, by the adoption of the process of 
downward displacement of the waste acids from the nitrated product by 
a layer of water ; for nitroglycerine a displacement process by which the 
layer of that liquid, separating on the surface of the waste acids, was 
caused to overflow from the top of the vessel by introducing waste acid 
from a previous charge at the bottom, led to an increased safety and 
yield, and saved height in the erection of a factory ; the chemistry of the 
process of guncotton boiling was worked out and placed on a scientific 
foundation ; and acetone, which in the process of drying the cordite had 
been allowed to escape into the air, was recovered from the drying stoves 
and saved for further use. These advances in manufacturing method 
were taken up by other manufacturers, both in the United Kingdom and 

In the technique of the manufacture of propellent explosives before 
the war this country then had advanced to a high pitch of efficiency, so 


that when the demand came for enormously increased quantities of pro- 
pellents, new factories, such as that of Gretna, took up the manufacture 
on lines already well established. 

Safety in manufacture had also been closely studied, and precautions 
introduced that commended themselves to private firms. It may be said 
in this connection that the application of the Explosives Act of 1875 by 
the Home Office Inspectors of Explosives has been of much benefit to the 
explosives trade in reducing casualties. Perhaps in no other country are 
precautions taken to such an extent as in Great Britain, so that to visitors 
from abroad they sometimes appear unnecessary and vexatious, but 
experience has shown that the policy is sound, especially as it brings into 
all sections of the work an atmosphere of carefulness and responsibility, 
with an eventual gain in health of the workmen and freedom from accidents. 

Research on explosives before the war was carried out at the Royal 
Gunpowder Factory and at the Research Department, Woolwich. At 
the former establishment, the chemistry of the products manufactured 
was investigated, especially with regard to the mode of decomjjosition of 
guncotton, of nitroglycerine, and of cordite ; their respective rates of 
decomposition at different temperatures were determined, a subject 
bearing on their behaviour on storage. Knowledge of this kind is essential 
in a Service such as ours, on account of the extremes of temperature from 
tropical to frigid to which explosives may be subjected in stations through- 
out the Empire. 

At Woolwich an experimental establishment had been set up on the 
instigation of Lord Haldane to deal with explosives and metals used in 
gunnery. Here the study of the chemical and explosive properties of 
all types of explosives was undertaken and methods were developed for 
determining their stability and sensitiveness. This knowledge found 
application in laying down criteria for the choice of explosives for use in 
a Service whose demands are exigent on account of the drastic conditions 
above mentioned, affecting both storage and the design of mechanism 
containing explosives. So far as the subject-matter is not considered to be 
confidential, this work has been published in scientific journals, so that it 
is available in connection with the study of the theory of explosive 

A new phase was entered with the declaration of war, and ultimately 
all chemical help was mobilised for the defence of the realm. A nucleus 
existed at Woolwich, where the small staff of eleven chemists had been 
occupied in the study of explosives and their application. In two directions 
this experience proved of importance, for it enabled immediate answers 
to be given to questions which would otherwise have necessitated pro- 
tracted storage trials, and it afforded the staff the training necessary to 
qualify them to meet the fresh demands that became urgent on the 
outbreak of hostilities. 

After the beginning of the war the increase of work imperatively 
called for a larger staff', and more chemists were appointed, until at the 
beginning of 1917, the home supply being exhausted, permission was 
obtained to withdraw from France members of the Sj^ecial Brigade, R.E., 
of whom more than thirty were transferred to the Department. Finally, 
the chemical staff numbered 107 chemists and physicists distributed in an 
organisation which had been gradually evolved, comprising sections for 


dealing with different classes of work, such as organic chemistry, physical 
chemistry, analytical and general chemistry, physical investigation, 
calorimetry, stability, pyrotechny, applications of high explosives, fuse 
design, and records. 

The manufacture of high explosives had not previously been under- 
taken by Government, and the known processes for making trinitrotoluene, 
which was early chosen as a Service high explosive, were unsatisfactory. 
One of the first subjects, therefore, taken up after the outbreak of war 
was the provision of an efficient and rapid process for the manufacture of 
trinitrotoluene, especially without the use of fuming sulphuric acid (oleum). 
From the results of a large series of nitrations in the laboratory, a process 
was evolved characterised by several novel features, and this was put to 
the proof on the semi-industrial scale of a quarter-ton, a plant being designed 
and erected in the Research Department, Woolwich, for nitration, in- 
cluding appropriate arrangements for the mixing and concentration of 
acids. This small plant substantiated in a remarkable way the process 
evolved from the laboratory work, and from the start turned out trinitro- 
toluene of good quality and yield. The process found immediate 
application in the large Government factories that were designed and 
erected by Mr. Quinan and also in numerous private works built at this 
time. The small-scale plant mentioned was used also for the purpose of 
training chemists, who proceeded to operate chemical plant in Government 
and private factories. 

A study of trinitrotoluene in all its aspects was undertaken, and much 
attention devoted to its chemistry, the proportions in which the isomers 
occur in the crude product being determined by thermal analysis, and 
investigations were made on their interactions, stability, sensitiveness, 
heat values, and explosive properties. Most of the scientific results of 
this work have since been published. 

When it became evident, as it soon did to Lord Moulton, that the 
supply of high explosives in use, lyddite and trinitrotoluene, would not 
suffice, the Research Department put forward mixtures of ammonium 
nitrate and trinitrotoluene, the amatols, as a result of a study of their 
properties and of their effects in shell-bursting trials. Gun trials confirmed 
these trials at rest, and the adoption of amatol as a high explosive quickly 
followed. Various methods of filling these mixtures into shell were at this 
time worked out, and many of them were applied on the very largest scale. 

It was found that 80/20 amatol (80 parts of ammonium nitrate to 
20 of trinitrotoluene) was less easy to bring to detonation than lyddite 
or trinitrotoluene itself, and it required special arrangements in the train 
of initiation of detonation. These were successfully devised, and good 
and trustworthy detonation of our shell was secured. Ultimately, amatol 
became practically the only explosive for land and aerial warfare, and 
justified the early estimate of its jiroperties and capabilities. It is 
economical in that it makes use of a cheap ingredient, and has explosive 
properties that render it very suitable for the purposes for which it is used. 
In 1917 the production was at the rate of about 4,000 tons a week. 

The Department continued the study of amatol, especially with regard 
to its chemical stability and compatibility with the various materials with 
which it came into contact. Certain impurities in ammonium nitrate were 
discovered to be objectionable, and investigation of these led to an 


improvement in the purity of the ammonium nitrate supplied. The 
manufacture of amatol and the modes of filling it into shell occupied the 
attention of a large staff of chemists attached to the factories, and an 
increase in knowledge of its chemical and physical properties led to 
improved methods of handling it. 

The Service propellent cordite required for gelatinisation in the 
course of its manufacture the solvent acetone, of which the supply ran 
short when the programme for propellents began to exceed all previous 
calculations. To meet this situation, cordite of the existing type was 
retained for Naval Service, but for Land Service a modification was 
introduced under the name of cordite R.D.B. (Research Department 
powder ' B '). This propellent could be made without any alteration in 
the plant required for the manufacture of cordite. Instead of acetone 
the solvent employed was ether-alcohol, and instead of guncotton a lower 
nitrate of cellulose was used. The great factory at Gretna, also built by 
Mr. Quinan, manufactured cordite R.D.B. exclusively, and this soon 
became the only propellent made in this country for the Land Service. 
It was produced both by Government and by private firms in enormous 
quantities. The alcohol was made in the country from grain, and ether 
was produced from it, so that dependence on sea-borne solvent was 
reduced. It was this need for alcohol that led to the restrictions imposed 
on that liquid when used as a beverage. 

Numerous problems arose in connection with these manufactures as 
they developed and in the application of the explosives in the various 
types of ammunition, and these necessitated the study of the explosives 
in all their aspects. A large addition to the knowledge already existing 
was thus acquired on the more theoretical side of the study of explosives, 
and much of this has been made available by publication. 

As the demand on our resources increased, and the necessity grew for 
investigating every source of supply and possible alternative, it came to 
pass that nearly every professor of chemistry in the country was mobilised 
for investigation in this field and in that of chemical warfare, and much 
valuable work was done by them, both of a research and inspectional 

For the manufacture of explosives and the operation of filling them 
into munitions of various kinds in the existing factories and the new ones 
which sprang up, a large staff of chemists, amounting to about 1,000, 
was required, and in this way many chemists whose earlier work lay in 
quite other directions, such as at the universities or in teaching posts, 
received an insight into technology and took control of workmen. 

During the war itself, instructional work in this subject was not 
wanting, for current progress in the factories under his control was dis- 
cussed in a systematic manner by Mr. Quinan with representatives of his 
staff, a course which led to important improvements. Although most of 
these war-time plants for the manufacture of explosives have been 
dismantled, much of the technical experience gained has been saved, and 
will be found incorporated in a series of memoirs (Technical Records of 
Explosives Supply) published by H.M. Stationery Office. The information 
set forth in these volumes is in a form which has a much wider appeal than 
to the explosives technologist only, and their study is commended to those 
who take up the subject of chemical technology in any of its aspects. 


In addition, factories for the production of substances not in them- 
selves explosive equally required the services of chemists, and many were 
employed in the production of such substances as methyl alcohol, acetone, 
and acetic acid. 

Instruction in chemistry is provided by the Fighting Services for 
Naval and Marine cadets at Dartmouth, and for Army cadets at the Royal 
MiUtary Academy and the Royal Military College, Camberley. For 
selected officers, both of these Services have a professorial stafE for 
providing systematic courses in theoretical and practical chemistry, with 
special reference to Service applications, at the Royal Naval College, 
Greenwich, and at the Artillery (formerly the Ordnance) College, Woolwich. 

Defence— Chemical Warfare. 

While our well-developed position of the great inorganic chemical 
manufactures was a source of strength when the demand came 
during the war for an enormous production of ammonium nitrate, for 
example, our neglect to foster a great organic chemical industry led to 
dangerous delays and improvisations. This was apparent from the 
beginning when several universities had to co-operate to produce a 
sufficient supply of local ansesthetics, and when presently our lack of 
dyes, photographic developers and sensitisers revealed our former 
dependence on foreign supplies. In November 1914 the Royal Society 
had set up a Committee to assist the Government, and this became an 
Advisory Committee. when, after May of the following year, the gas attack 
caused the British Government, which up till then had scrupulously 
refrained from its use, to retaliate with that weapon. Special companies 
were created of chemists whose work often had little of a chemical aspect, 
but many of these men, in twelve to eighteen months, had to be withdrawn 
for research and control of plant. Chemical advisers were appointed to 
the armies and for liaison purposes, a central laboratory for rapid 
identification was established in France, and co-operation was effected 
with the physiologists. At home assistance was afforded to chemical 
contractors, and the manufacture of respirators to meet needs rapidly 
becoming more complex was carried out with great vigour and efficiency. 
The increasing importance of gas warfare led to a proving ground at 
Porton being acquired, when the research which had been carried out at the 
Imperial College at South Kensington became centralised there. As the 
final proof of explosive projectiles is carried out at Shoeburyness, it was 
now possible on this new proving ground to settle questions relating to 
the filhng and correct performance of chemical shell, thus enabling the 
Chemical Warfare Designs Committee to recommend ammunition to meet 
the needs of a situation which was continually developing, until the 
proportion of chemical shell compared with high-explosive shell was 
finally a large one. 

In the ramifications of this work all the chemical skill in the universities 
not already applied to explosives was mobilised, since the demand for new 
designs involved the manufacture of new substances for shell, bombs, and 
grenades, new smoke and incendiary compositions, and continuous research 
and experimental work both on the offensive and defensive sides. 


In a few cases only was the country capable of expanding its existing 
manufactures, as in the case of phosphorus and chlorine ; it was not 
equipped for the home production of phosgene, arsenical compounds, or 
mustard gas. New factories had therefore to be erected and staffs 
specially trained, in striking contrast to the existence in Germany of 
standardised plant capable of rapid transference from one purpose to 
another with little alteration : an example of this was their manufacture 
of arsenical preparations in the azo-dye sheds. 

As a result of an intensive study of absorbent substances, our respirator 
was never beaten, and it is claimed that, although our output was smaller, 
the better employment of gas, tactically for surprise, lay with us. Starting 
late and entering a field entirely new, we were able while there was yet 
time to protect the soldier, and to make a reply on the offensive side that 
was rapidly becoming more and more effective. 

Not all of the work specially devoted to chemical warfare has been 
without its effect on peace-time requirements. Thus liquid chlorine, of 
which very little was made in this country before the war, is now being 
prepared electrolytically and transported by rail in tank waggons for use 
in various industries. For the preparation of phosgene, which had been 
used in Germany in the manufacture of dyes of the triphenylmethane 
series, better methods were discovered in this country, so that cheaper 
and purer phosgene is being used here for the first time to prepare the 
important group of colours known as the Victoria blues. Improved 
methods are now available for the manufacture of arsenical compounds, 
such as arsenic trichloride, a substance used for combating the growth 
of prickly pear in Australia ; and mention may be made of the work of 
Professor Moureu in France on the stabilisation and concentration of 
acrolein, as it has led to the production of a substitute for celluloid from 
that body. In addition, the study of many of the bodies used for chemical 
warfare has been of value from the aspect of the elucidation of their 
chemical constitution. 


When the part played by metals in the history of civilisation is con- 
sidered, the development of some more durable alloy or some stronger 
metal appears intimately linked with a distinct advance constituting a 
new age, often characterised by eponymous association with the metal. As 
the possession of some superior metal may give ascendency to a people, 
it is natural that States should show interest in metallurgy, both militarily 
and to maintain the standard of the medium of exchange. It is thus seen 
that iron and the precious metals gold and silver have for the most part 
interested the modern State, the metallurgy of the other metals only more 
recently coming in for attention on military grounds. Accordingly, we 
find the armourer and the minter holding important positions in early 

It must be stated at the outset that the relations in Great Britain 
between the State and metallurgical science before the war of 1914 to 1918 
were for the most part sporadic, the great developments in that science 
being to a large extent independent of the State. It undoubtedly exerted, 
however, an influence on the nature and quality of metallurgical products, 
of which it was a large user for warlike, structural, and shipbuilding 


purposes, by specifying the conditions of their acceptance : standards 
established by the Government, often based on inquiry and experiment, 
gave confidence to other users and resulted in the improvement of industrial 

Although iron-making had flourished intermittently since the Roman 
occupation, and had reached considerable proportions under Elizabeth, 
no great contribution to knowledge can be attributed to Great Britain in 
the progress of metallurgy until the restriction of the cutting down of 
timber for charcoal towards the end of the sixteenth century forced into 
consideration the use of coal for smelting, the pioneer work being that of 
Dud Dudley, who in 1642 cast iron cannon at his foundries for the Royalist 
troops. It was his experience as an Admiralty official that brought Cort, 
more than 100 years later, to recognise the inferiority of English wrought 
iron, and to leave the Service for the purpose of improving existing processes 
so that his successful wrought iron was accepted towards the end of the 
eighteenth century for anchors and iron work in the Royal Navy. His 
invention of the puddling process led to great prosperity in the iron trade. 

The need to meet Government requirements became similarly urgent 
in the case of steel, which in its earlier production as puddled steel so failed 
in uniformity of composition that as a material of construction it could 
not be used by the Admiralty, nor permitted by the Board of Trade. 
Bessemer's great advance of converting molten iron cast into steel by 
blowing air through it, described in 1856 to this Association, enabled him 
to propose a material more suitable for guns and projectiles than the cast 
iron then employed. Bessemer steel came into use for many purposes, 
and its production increased rapidly, but boiler plates submitted to the 
Admiralty still showed great variations in carbon content. Meanwhile 
the rival open-hearth process was steadily developed and established 
by Siemens. In 1875 the Director of Naval Construction had pointed 
to the danger due to lack of uniformity of steel made by the converter 
process, but in 1879 he was able to report the success of the new open-hearth 
steel. The Government challenge had been taken uj) by Siemens, who 
produced a steel to meet all its specifications, so causing its acceptance 
for Admiralty work, and its admission by the Board of Trade for structural 

After Thomas and Gilchrist had in 1877 solved the problem of dephos- 
phorising iron by the basic process, the Admiralty instituted an inquiry 
as to its properties, which led to an ofiicial recognition of basic steel, thus 
greatly enlarging the source of supply through the use of native ores. 

Among the men who assisted the Government in these inqiiiries was 
Dr. Percy, who placed metallurgy in this country on a scientific basis, 
while lecturing on that subject at the Royal School of Mines and at the 
Ordnance College. Abel, appointed War Department Chemist in 1854, 
gave much attention to the use of iron and steel for military purposes, 
investigating the question of erosion of guns and throwing new light on 
the constitution of steel by his isolation of ¥e.JJ. He did good service in 
convincing the great ironmasters of the importance of chemistry in their 
industry. To Roberts-Austen also. Chemist and Assayer to the Mint, 
many Government inquiries and commissions were ijidebted for advice 
on the subjects he had enriched by his researches, such as the physical 
constants and mechanical properties of metals, the effect of impurities, 


the cementation of iron, heat treatment, and many others, including the 
first ' freezing-point ' curve of a series of binary alloys in 1875. It was in 
consequence of these that his co-operation was invited by the Alloys 
Research Committee, whose first six reports contained a great deal of his 
work, covered a wide field, and did much towards the realisation by engineers 
of the value of microscopical and thermal methods in the study of metals. 
Later reports to this committee, whose work in 1902 was transferred to the 
National Physical Laboratory, have maintained their high standard, and 
have been contributed to by such workers as Carpenter, Hadfield, and 

The last of these reports, the eleventh, embodies work at the National 
Physical Laboratory from 1914 to 1918, the year when that institution 
became a part of the Department of Scientific and Industrial Research. 
It deals with light alloys, the need for which the war has emphasised, 
especially in connection with aircraft. For this purpose the Laboratory's 
work has resulted in furnishing alloys of aluminium with zinc and copper, 
with copper and manganese, and with copper, nickel and magnesium, 
possessing remarkable and useful properties, such as high tensile strength 
at ordinary and also at raised temperatures. 

Since the war light aluminium alloys continue to be studied at the 
National Physical Laboratory, which is the Government establishment 
where metallurgical research is carried out mainly for the advancement of 
knowledge. Here has been worked out the constitution of many important 
systems, binary, ternary, and quaternary, in which aluminium is the 
largest constituent, and the wire models constructed for the ternary alloys 
have proved of great value in the study of their constitution. Such ques- 
tions as age-hardening have been investigated and the cause ascertained. 

Systems with copper as the dominant metal have been investigated 
as regards their constitution, as well as the effect on their mechanical and 
electrical properties of known additions of other substances that may be 
present as impurities. 

But attention is also being given to ferrous alloys for whose investiga- 
tion specially pure components have to be prepared, in order to eliminate 
the effect of impurities of which a very small proportion may often have 
a marked influence on the product, and several equilibrium diagrams 
with iron as the main component have been worked out. Research on 
the more ph^'^sical side includes investigations on the heat evolved during 
the plastic deformation of a metal, on the effect of heat treatment and 
composition on the magnetic properties of tungsten steels, on fatigue, and 
on the physical constants of metals. By the application of X-ray analysis 
to the crystal structure of metallic systems, Rosenhain has obtained 
confirmation of his conception of the nature of solid solutions. 

The chemical section of the National Physical Laboratory carries out a 
large amount of work in connection with these researches, the investigation 
of methods of analysis, and the preparation of standards for the analysis 
of steel, as well as chemical work of a non-metallurgical nature. 

Maintained by the Fighting Services since 1904 to increase the efficiency 
of the metals used in the manufacture of ordnance and armament, the 
Metallurgical Branch of the Research Department, Woolwich, increased 
in numbers, building and equipment during the war, and at present employs 
about 25 metallurgists. It has been occupied for the most part with steel, 


the heat treatment of which in relation to its mechanical properties has been 
the subject of close study, resulting in improved gun forgings being delivered 
by the makers. Two main types of steel have been under consideration, 
those which would give a minimum yield point of about 35 tons per square 
inch when treated in large masses, and those at about 25 tons. As a result 
much information has been acquired on the properties and heat treatment 
of steel containing various proportions of nickel, chromium, moly- 
bdenum and vanadium. The study of the elastic properties and of the 
erosion of gun steel has been of importance to gunnery. The Moore adap- 
tation of the Brinell hardness test, in which a small ball and load are used 
ina specially designed machine, was originally developed in the Department 
for testing small-arm cartridge cases, and has since found many other 
important applications here and elsewhere. 

Among other investigations on non-ferrous metals, those on ' season- 
cracking ' of brass and its prevention, and on methods of extrusion, have 
been productive of useful results, and in connection with the Non-Ferrous 
Metals Research Association, work is in progress on the casting of brass 
to produce sounder ingots, on the die-casting of brass and bronze, and on 
the failure of lead cable sheathing by cracking. 

During the war, the use of substitutes, the easing of specifications to 
increase output with safety, the examination of enemy ammunition, and 
the tracing of causes of failure and discovery of remedies provided a large 
field for investigation. 

The other aspect of metallurgy of special interest to the State, that of 
minting, has a long history ; from early times the need for a high and 
uniform standard of coinage, and the crime of debasing it, have been 
recognised. The difficulties that confronted the early assayers, without 
methods of quantitative analysis and with no fine balances, are apparent 
from the description of their methods, but it may perhaps be held that 
these needs as they became borne in on the early assayers and their 
frequent collaborators the alchemists, led the way to the appeal to weighing 
in chemical work. 

As early as 928 a.d. laws were proclaimed by King Athelstan appointing 
' mynteres ' whose products were scrutinised at the trial of the pyx ; later, 
in 1 180, supervisors of the coin manufactured by ' moneyers ' were appointed. 

An official mention occurs in the reign of Edward I. of a Guild of 
Goldsmiths in London, which had, however, existed since 1180, in an Act 
providing for the assay of silver vessels by the Wardens of that craft. 
The earlier writings on the subject of assaying are those of Germans, of 
whom Queen Elizabeth brought over a number to introduce their methods 
and assist in the development of the resources of the country. 

The course of testing seems to have been originally by means of the 
touchstone, supplemented much later by observing the effects of acid on 
the trace left by drawing the metal over the stone, the method of deter- 
mination of density, the cupellation method, officially recognised by 
Henry II., and finally the wet method of analysis. 

To safeguard the fineness of the coinage a King's Assayer was appointed 
in 1222, a Master of the Mint manufacturing the coin under contract, and 
a Warden acting on behalf of the King. A Commission, having toured 
the Continental mints, reported in 1870 in favour of the present organisa- 
tion of the Chancellor of the Exchequer being Master of the Mint in virtue 


of his office, a Deputy-Master being responsible for the administration, 
while the valuation of bullion and questions of assay are the duties of the 
Chemist and Assayer. 

Many of the Mint officials have contributed largely to metallurgical 
knowledge. One of them, William Humphrey, in 1565 received the first 
patent for making brass, and a later one, Sir John Brattle, communicated 
work to the Royal Society shortly after its foundation on the oxidation 
of lead. Sir Isaac Newton when Warden is said to have himself conducted 
experiments on the composition of foreign coins. The melting-points of 
metals were studied in conjunction with Wedgwood by Alchorne, who was 
appointed Assay Master in 1789. From 1851 to 1870 several distinguished 
men of science, such as Hofmann, Graham (who in 1866 published a work 
on the effect of the occlusion of gases in metals) , Miller, and Stenhouse, were 
officials of the Mint; but in 1870 it was considered preferable to conduct 
the chemical operations of assaying within the Mint itself, and Roberts- 
Austen, to whose pioneering work in metallurgy allusion has been made, 
was appointed. To his successor, Kirke Rose, are due many advances in 
knowledge of the precious metals. Thus, researches at the Mint have been 
directed to the investigation of metallic systems of gold with silver and 
other metals, the means of avoiding brittleness in gold coins, the electro- 
lytic refining of gold, the mechanism of annealing of metals, the surface 
tension of solid and molten metals, as well as to improvements in the 
technique of the methods of assay. 


In reviewing the influence of our science in its application to Revenue 
questions, it is convenient to consider historically the substances on which 
the State has levied duties. 

In the older tariffs, fixed charges were levied on goods considered as a 
whole, but a time arrived when the chemist was called in ; it then became 
possible to make an assessment on the ground of a percentage. Un- 
certainty prevailed, therefore, as to the basis of taxation and gross 
adulteration flourished until scientific safeguards were introduced. 

The chief substances with which the chemist is at present concerned 
from the Revenue point of view are the following : (1) liquids containing 
alcohol ; (2) tobacco ; (3) sugar % (4) tea and cocoa ; (5) dyestuffs, under 
the Dyestuffs (Import Regulation) Act, 1920 ; (6) substances taken 
under the Safeguarding of Industries Act, 1921. 

(1) Liquids containing alcohol. — On imported wine Richard I. imposed 
a duty, and as time went on complications were caused by the intro- 
duction of imposts for various purposes, including reprisals. 

Acts were passed, as in the time of Charles II., for preventing the 
reprehensible practices of mixing wine and vitiating it with other substances 
such as cider, sugar, herbs and vitriol ; it is still forbidden to mix wines of 
different sorts. 

The difficulty of distinguishing the strength of alcoholic liquids is 
apparent in the older enactments, when, for example, the Legislature 
describes brandy as a ' strong water perfectly made imported from beyond 
the sea,' and it was not until the reign of William III. that they were 
assessed, if not in proportion to their strength, at least in some relation 


thereto. The first step was their separation into 'single' and 'double' 
proof, a rough and inconclusive one, but accounting for the use of a term 
still recognised as that on which the full statutory rate of duty is leviable. 
For charging Revenue the gallon was first taken as a measure in 1825, 
but definite alcoholic strength was not introduced as a basis until 1860, 
under a treaty with France, while a little later, in 1862, Parliament dis- 
tinguished between wines above and below 26 degrees of proof spirit, this 
figure being raised in 1886 to 30 degrees. 

The want of some accurate method of test had been felt, and it is 
interesting to follow the gropings after a method for recognising a standard 
strength of alcohol. Thus observations on the surface tension of spirits 
were employed, for Postlethwaite in 1751 described as a mark of their 
being up to proof the length of time elapsing before bubbles disappear 
from the surface of the liquid contained in a glass tube which had been 
shaken, but as he believed this method may be falsified, he recommended 
for more accurate work ' the essay instrument, or hydrostatical balance,' 
although for business men it would be sufficient to burn a measured quantity 
of the spirit in a metal cylindrical vessel immersed in cold water, and 
measure the remainder, which should be equal to half the original volume, 
if the spirits were proof. Although ' Boyle's bubble ' had been described 
in 1675, and Moncony's areometer in 1679, the first instrument generally 
adopted by the Revenue in 1730 was the hydrometer of Clarke, legalised 
in 1787. It is complicated, however, and its temperature correction by 
' weather weights ' was unsatisfactory, so that Parliament gave instructions 
for ' proper experiments to be made.' 

At the request of the Government to the President of the Royal 
Society, Sir Charles Blagden (Secretary) and one of the clerks, Mr. George 
Gilpin, undertook to make experiments on the specific gravity of alcohol 
and water in varying proportion. These experiments, conducted with 
exemplary care and ability, were reported to the Royal Society in 1790, 
1792, and 1794, and formed the basis for the tables of Sikes, whose hydro- 
meter became the sole legal instrument in 1818, and is still in use. These 
tables remained legal for nearly a hundred years, but in 1916 were replaced 
by a new and extended set, prepared under the supervision of Sir Edward 
Thorpe at the Government Laboratory, whence also in the same year were 
issued comprehensive tables of spirit strengths for use with pyknometers, 
as these had shortly before been legalised for alternative use in the deter- 
mination of alcohol. Both of these sets of tables were founded on the 
definition of proof spirit contained in the Act of George III., which is, that 
spirit which at the temperature of 51° Fahr. weighs exactly 12-13 parts of 
an equal measure of distilled water. In other words, it contains 49'28 
parts by weight of pure alcohol and 50"72 parts by weight of distilled 

As these tables refer only to alcohol-water mixtures, all disturbing 
substances must be removed before the strength of liquids is determined 
by hydrometer or pyknometer. The methods of freeing spirit in com- 
mercial articles from everything but water were investigated and laid 
down by the Government Laboratory in 1903 by Thorpe and Holmes. 

From the point of view of trade it is highly important to have free use 
of ethyl alcohol, while from that of the Revenue it is essential to prevent 
the use of such duty-free spirit as a beverage. The most effective menns 
1924 V 


to meet both requirements is to denature spirit which is to be delivered 
duty-free for trade purposes, and the question of the choice of a suitable 
denaturant is by no means easy. So long ago as 1856, the Government 
Chemist of the day, Mr. Phillips, proposed the addition of 10 per cent, 
of crude wood naphtha, and this has been found satisfactory for most 
purposes. The proposal was submitted to and approved by three well- 
known chemists of that day, Graham, Hofmann, and Redwood, and this 
present year circumstances have necessitated the addition of a further 
nauseating ingredient, pyridine, in addition to mineral naphtha which 
was added in 1891. Mineralised methylated spirit which is sold without 
Revenue control, excepting that a licence is needed, contains this pro- 
portion, industrial methylated spirit 5 per cent., and power alcohol 2h per 
cent, on the alcohol. 

That some misunderstanding exists as to the facilities available for the 
use of alcohol in commerce in the United Kingdom appears from an 
article recently communicated to the Ottawa Section of the Society of 
Chemical Industry, in which are contrasted a considerable number of 
compositions approved in Canada with the apparently small number 
legalised in Great Britain. It might be well, therefore, briefly to indicate 
the position, in order to make clear the facilities that are available. 

Mineralised methylated spirit consists of a mixture of 90 parts of 
alcohol, 9| parts of wood naphtha, and half part of crude pyridine, 
together with |th of 1 per cent, of mineral naphtha and 0'025 of an 
ounce of methjd-violet dye in each 100 gallons of the mixture. It is sold 
under licence, but is otherwise unrestricted and duty-free. 

Power methylated spirit, prepared in accordance with the following 
formula : 92 parts of alcohol, 5 parts of benzol, 0"5 part of crude pyridine, 
and 2'5 parts of wood naphtha, together with 0'025 of an ounce of Spirit 
Red III. dye in each 100 gallons of the mixture, is also sold without 
restriction and freedom from duty when mixed with 25 per cent, of hydro- 
carbons or denatured ether or some other substance approved by the 
Commissioners of Customs and Excise. 

Industrial methylated spirit, consisting of 95 per cent, of ethyl alcohol 
and 5 per cent, of wood naphtha, can be obtained for the arts and manu- 
factures under the authority of the Board of Customs and Excise, under 
bond and certain not very onerous restrictions. Between three and four 
million bulk gallons are annually used for the making of such products as 
varnishes, linoleum, soap, solid medicinal extracts, ether, toilet preparations 
for external use, fine chemicals, photographic plates, dyes, surgical dressings, 
fireworks, and for many other purposes, including its use in the chemical 
laboratories of colleges, schools and works, and for preserving museum 
specimens. It is free from duty, but must not be present in an article 
capable of internal use, either as a beverage or a medicine. 

Duty-free pure alcohol is allowed by the Board of Customs and Excise 
for scientific purposes to universities and public institutions for teaching 
and research, and specially denatured alcohol in arts and manufactures 
in which the use of the industrial methylated spirit is unsuitable. 

The pure alcohol is allowed to colleges and public institutions for 
teaching and research purposes without any onerous conditions beyond 
the keeping of a stock account. Pure methyl alcohol is permitted by the 
Board of Customs and Excise to be used duty-free in arts and manufactures 


under regulations similar to those for industrial methylated spirit, and is 
largely used in the manufacture of formaldehyde, of methyl derivatives 
among dyestuffs and fine chemicals, and for the purpose of crystallisation. 

The specially denatured alcohol, also free from duty, is allowed to 
manufacturers under restrictions compatible with the safety of the Revenue, 
a very wide choice of denaturants being permitted. When, as frequently 
happens, a suitable denaturant is found in some intermediate product, or 
acid used, or produced during the manufacturing operations, or when the 
alcohol is a constituent of some mixed solvent, permission is the more 
readily granted for its use. An example of progressive policy in the use 
of pure spirit is the recent decision of the Board of Customs and Excise to 
allow the use of pure ethyl alcohol denatured with 2 per cent, of pure 
methyl alcohol in the production of insulin, without onerous Excise 
restrictions. It is understood that the recent action of the Board of 
Customs and Excise has been received with satisfaction by the Association 
of British Chemical Manufacturers. The quantity of pure and specially 
denatured alcohol used during last year was about half a million gallons. 

In the case of duty-paid spirits used for medical purposes, such as 
the preparation of tinctures, &c.., and for scientific purposes in chemical 
laboratories, a rebate is allowed under the Finance Act of 1920, amounting 
to about 80 per cent, of the duty. 

While the responsibility rests on the Board of Customs and Excise of 
safeguarding the illicit use of alcohol, chemists have been represented on 
such commissions as that of the Industrial Alcohol Committee of 1905, 
whose recommendations led to the Revenue Act of 1906, in which the 
proportion of wood naphtha was reduced to 5 per cent., permission being 
also given for the payment of an allowance of 5d. per proof gallon or about 
8d. per bulk gallon on British spirits used for industrial purposes, in 
consideration of the increased cost of the spirits owing to Excise 

An important alcoholic liquid that has been liable to imposts from the 
time of Charles II. is beer, and it was charged according to its strength or 
weakness as j udged by the palate. After the application of science to brew- 
ing about the middle of the eighteenth century, the saccharometer was 
introduced, the pattern due to Bate being still in use for Revenue purposes. 
In 1850 an investigation made by the then Government Chemist, Mr. 
Phillips, and his assistant, Mr. Dobson, established a quantitative relation- 
ship between the proportion of alcohol produced in the process of fermenta- 
tion and the solid matter previously in solution in the worts that had been 
fermented, and tables were prepared for use in determining the original 
gravity of the beer, i.e. the specific gravity of the worts before fermentation 
had begun. These tables, after verification by Professors Graham, 
Hofmann, and Redwood, were employed in the Revenue service until 1914, 
when they were superseded by revised ones prepared by Sir Edward Thorpe 
and Dr. Horace T. Brown, these being rendered necessary mainly owing to 
the employment in brewing of many substitutes for malt unknown in the 
earlier days. As a rapid means for determining the original gravity the 
immersion refractometer is constantly in use in the GovernmentLaboratory. 
This laboratory also furnished the scientific evidence for the Inland 
Revenue Act of 1880, which enabled brewers to use a great variety of 
substances for brewing. 

F 2 


(2) Tobacco. — Not long after its introduction Elizabeth imposed a 
small duty on tobacco, which under James I. met with not only his famous 
Counterblast, but an increased duty of 6s. lOd. a pound. Although Charles I. 
continued its repression, and the Puritans regarded its use as ' profanity,' 
the snuff-box became in the time of Queen Anne a necessity of the fashion- 
able world. A regular trade sprang up in preparing substitutes from various 
leaves, and numerous enactments proved incapable of preventing smugghng 
and adulteration. It was recognised that systematic chemical and micro- 
scopic examination had to be applied to the problems arising from this 
adulteration, and in 1843 a laboratory, which ultimately grew into the 
Government Laboratory, was erected to check it, with the result that this 
form of fraud was almost entirely stamped out. A strict watch is still 
maintained on all tobacco for home use or for export, both from the point 
of view of absence of foreign materials and of its hygroscopic condition, as 
the Revenue charge is based on the latter. Chemical control is exercised 
over the use of preservatives and the denaturing of tobacco before it can 
safely be allowed out of Revenue control. 

(3) Sugar. — In the reign of James I. the importation of sugar was 
already sufficiently large to make it worth while to impose a duty on it, 
until at the beginning of the nineteenth century this amounted to 30s. a 
hundredweight. Before 1875, when the duty was abolished, disputes had 
arisen as to its proper assessment on the basis of description and character. 
When it again became dutiable in 1901 an extended classification was based 
on the polariscope scale, and sugars in numerous preparations had to be 
determined chemically. This has raised several difficult questions of 
chemical procedure, especially when natural as well as added sugars are 

(4) Tea and cocoa. — Attempts were made in 1777 to stop the adultera- 
tion of tea with foreign and exhausted leaves and other matter, but it was 
not until 1875 that the Sale of Food and Drugs Act placed on the Revenue 
authorities the responsibility for examining tea on importation. This is 
done on an extended scale by the appUcation of chemical, microscopic, and 
practical tests. There has been, however, no imposition of standards in 
the United Kingdom, as is the case in Canada and the United States. 

The duty, and the drawback on the duty, on cocoa preparation has 
introduced chemical problems into the system of Revenue control, some of 
them of considerable difficulty, as, for example, those connected with the 
use of substitutes for the natural cocoa fat. 

(5) Dyestuffs, under the Dyestujfs Import Regulation Act, 1920. — The 
importation of dyestuffs under this Act is controlled by a Dyestuffs Advi- 
sory Licensing Committee, on which distinguished chemists represent the 

Importation of synthetic dyestuffs and intermediates is prohibited 
except under licence, and although the individual substances leave httle 
room for doubt, more difficult questions come before the Government 
Laboratory in the case of substances containing a coloured ingredient. 

(6) Substances taken under Safeguarding of Industries Act, 1921. — 
Part I. of this Act imposes an ad valorem duty on the products of certain 
' Key ' industries, of which the fine-chemical manufacturing trade is one. 
After the Act had passed into law, the Government Laboratory became 
concerned with the chemical aspect of that section which has gained 


notoriety through legal inquiries involving the precise significance of chemi- 
cal and technical terms. But apart from such matters, many difficult 
chemical problems have arisen in determining the composition of the 
great variety of chemical substances imported. Thus it has proved a 
task of some magnitude to deal with about 8,000 subjects per annum, 
when their examination may include the quantitative determination of the 
ingredients of materials such as synthetic perfumes, photographic deve- 
lopers, medicines, colloidal preparations, alkaloids, &c. The grade of a 
specified material has also frequently to be assessed, and this involves a 
special knowledge of its manufacture and use. 

The effect of the war was generally to increase the amount of existing 
duties and to impose fresh ones. The former condition led to increased 
vigilance in the chemical control on account of the introduction of substi- 
tutes to replace the dutiable substances ; the latter were imposed as a 
post-war condition and are described above. In connection with the 
war-time prohibition of exports, not only of munitions but practically 
of all useful commodities, the services of the Government Laboratory were 
required to decide as to the nature of about 20,000 substances, including 
cases in which the prohibited goods were skilfully disguised. 

For all matters involving chemical advice the Board of Customs and 
Excise applies to the Department of the Government Chemist, who main- 
tains on his staff for this section of the work a sufficient number of chemists 
and assistants to make the necessary investigations and deal with the 
chemical points at issue, as well as to carry out the necessary practical 
work, both in London and at several of the ports. This aspect of the work 
of the Government Laboratory involves a knowledge of Revenue law and 
precedent as well as an intimate acquaintance with a large range of chemical 

The importance of chemical control in safeguarding the Revenue is 
obvious. Withincrease in the number of subjects brought under supervision, 
the greater refinements and accuracy demanded, the investigation of new 
processes, and the amount of chemical work, the number of chemists is 
rapidly increasing. 


The earliest legislation in respect of food dealt with articles from the 
Revenue standpoint rather than from that of safeguarding users against 
adulteration. Thus, the Adulteration of Coffee Act of 1718 refers to evil- 
disposed persons who make use of water, grease, butter and such-like 
materials for addition to coff'ee, ' whereby the same is rendered unwhole- 
some and greatly increased in weight, to the prejudice of His Majesty's 
Revenue and the health of his subjects.' Similarly, the Tea Act of 1730 
refers to the use of various materials and operations for sophisticating 
tea, ' to the prejudice of the health of His Majesty's subjects and the 
diminution of the Revenue.' The Tea Act of 1776, which deals specifically 
with the preparation of other leaves for use in imitation of tea, gives as an 
additional reason ' the injury and destruction of great quantities of timber 
woods and underwoods.' 

Since this legislation was mainly for the prevention of fraud on the 
Revenue, it was left to the Crown to take such steps as were considered 
necessary to ascertain the purity of the articles in question. To this end 


the Inland Revenue Laboratory, which was established in 1842 primarily 
for testing tobacco, became also the laboratory for the analysis of dutiable 
foods, such as tea, coifee, pepper. In this connection it is of interest to 
note that the Government at times sought assistance from distinguished 
chemists not on its staff, as when Thomas Graham, at University College, 
London, carried out for the Board of Inland Revenue an inquiry into the 
chemical means of detecting vegetable substances mixed with coffee for 
the purposes of adulteration. Among the early pioneers in the chemistry 
of food may be mentioned Dr. Hassall, who was the analyst of the ' Lancet 
Sanitary Commission,' and published the reports of that body under 
description of ' Pood and its Adulteration.' 

Besides the enactments with regard to certain dutiable foods referred 
to above, legislative action was taken with respect to bread, the Bread 
Act of 1822 dealing with the sale of bread in London and district, and 
that of 1836 with the sale of bread outside the London area. There was 
no provision for analytical examination of samples under these Acts, which 
still remain in force. 

By the efforts of Lyon Playfair on matters of sanitation and the work 
of the Royal Commission on the Health of Towns of which he was a 
member, pubUc opinion was being awakened during the 'forties to the 
social importance of the health of the community, a movement in which 
the Prince Consort took an enthusiastic part. This led to the Commission 
of 1869 and the foundation of the Local Government Board, through which 
the safeguarding of public health in England was systematically organised. 
From this Board and its successor, the Ministry of Health, a series of useful 
reports on questions of food have issued, most of which have involved 
chemical investigations. 

In 1855 and again in 1856 a Committee was appointed by Parliament 
to inquire into the ' Adulteration of Food, Drinks and Drugs.' It was 
evident to these Committees that some provision for the chemical analysis 
of samples was necessary, but they made no provision for samples to be 
taken. This and other matters were provided for in an amending Act, 
which came into force in 1872. A Select Committee of Parliament was 
appointed in 1874 to inquire into the working of these Acts, and as a 
result of their report another Act, that of 1875, was substituted. By this 
Act the Local Government Board was given power to require evidence of 
competence from analysts, and the Inland Revenue Laboratory (now the 
Government Laboratory) was appointed as the authority to which Courts 
of Law could refer disputed cases. 

The Act of 1875 has been amended and extended b)' the Acts of 1879 
and 1899, and other Acts have been associated or incorporated with it, 
such as the Margarine Act of 1887 and the Butter and Margarine Act of 
1907, the whole series being referred to collectively as the Sale of Food 
and Drugs Acts, 1875-1907. 

The provisions in the above Acts affecting chemists may be summarised 
as follows : (1) the appointment of public analysts by local authorities is 
compulsory ; (2) the Ministry of Health and the Ministry of Agriculture 
(when the interests of agriculture are in question) have power to step in 
if the local authority fails to utilise the services of the public analyst ; 
(3) the appointment and dismissal of a public analyst by a local authority 
are subject to the approval of the Ministry of Health ; (4) the analyst must 


afford the Ministry evidence of his competence for the work. It is the 
practice of the Ministry to accept for such purpose the Diploma of the 
Institute of Chemistry, together with the Certificate of that Institute in 
Therapeutics, Pharmacology and Microscopy. 

The position of the Government Chemist in the administration of the 
Acts is as follows : (1) the Acts provide that in the hearing of any com- 
plaint in a court of justice the magistrates must, at the request of either 
party, and may themselves without any previous request, send the 
reserved portion of the sample to the Government Chemist for analysis. 
This provision is taken advantage of in a number of cases each year, and 
gives rise to a considerable amount of interesting work relating to methods 
of analysis, the alteration in food on storage, and the figures to be taken as 
standards for genuine articles'. The necessity for such investigation is at 
once apparent in the case of milk, since samples cannot under ordinary 
circumstances reach the laboratory before the expiry of at least three or 
four weeks, and the fermentation that has taken place in this time has 
resulted in the loss of solid matter. 

(2) The Acts provide for the examination at the Government Laboratory 
of samples of imported tea, margarine, and various dairy products, the 
object being (a) to prevent adidterated food of this character entering the 
country, and (6) to ascertain whether it conforms to the standards laid 
down for such food. 

It may be pointed out that there is nothing in the United Kingdom 
corresponding with the series of food definitions and standards which exist 
in some of our Colonies, and in a marked way in the United States. The 
main provisions of these Acts are briefly that (1) no person shall mix any 
article of food with any ingredient so as to render the article injurious to 
health, and (2) no person shall sell to the prejudice of the purchaser any 
article of food which is not of the nature, substance and quality demanded 
by such purchaser. A few definitions and standards are, however, given 
in the Acts, and these have been added to by Regulations under the Acts, 
or by Regulations made under the Public Health (Regulations as to Food) 
Act, 1907, the Licensing Act, 1921, and the Milk and Dairies Act, 1922. 
Before regulations on questions of limits have been issued, it has been 
customary for the Crown to institute an inquiry into the particular subject. 

A brief summary of the definitions and standards thus fixed is as 
follows : (1) the strength of spirits must not be reduced more than 35 
degrees under proof ; (2) standards have been fixed for milk, separated 
milk, condensed and dried milks ; (3) limits have been set up for water 
in butter, milk-blended butter and margarine, and for butter fat in marga- 
rine ; (4) the addition to milk of water, preservative, colouring matter, 
separated or reconstituted milk is prohibited; (5) cream must not be mixed 
with a thickening substance, and the conditions with regard to the addition 
of preservative to it have been laid down. 

In its care for the purity of drinking water the State has made several 
enactments. It may be said that this country led the way as the result 
of the great work of Frankland in devising means for determining the 
potable qualities of water, and in pressing for pure supplies. An enormous 
volume of useful work was carried out by the Royal Commission on Sewage 
Disposal of which Ramsay was a member. This sat from 1898 until 1914, 
when it dissolved, having projected further work on industrial effluents 


and their effect on river water, work which is just recently being followed 
up by an Advisory Committee to the Ministry of Agriculture and Fisheries. 
The contamination of the atmosphere is a subject of concern to the 
Ministry of Health working under Acts from 1863 onwards. Limits have 
been set to the discharge of noxious and offensive gases, and the control 
is in the hands of a number of chemical inspectors, who have in addition 
carried out a large number of investigations of importance to general health 
and to industry. The contamination of the air in cities is watched by the 
Meteorological Office, which records the quantity of soot falling in different 
parts of the country. By such means the public conscience is being 
awakened to the necessity for carrying out work on the provision of a 
smokeless fuel, a subject engaging the attention of the Government Fuel 
Research Station. 

Chemical control is also concerned with the question of danger to health 
arising in certain trades, such as that of the manufacture of matches, in 
which red was substituted bj- law for white phosphorus, with the limitation 
of lead in glazes, with the nature of the gases in mines, and with manufac- 
tures in which poisonous substances such as nitrobenzene and nitrous 
fumes are produced. 

In 1900 there was a serious outbreak of sickness attributable to poison- 
ing by arsenic, and a Royal Commission was appointed to inquire into 
the cases and to ascertain by what safeguards the introduction of arsenic 
to food could be prevented. A very large amount of chemical work was 
carried out in connection with this inquiry, and considerable attention 
was paid to the methods for the detection and examination of arsenic. 
Among those contributing specially to the problems may be mentioned 
Dr. George McGowan, the Government Laboratory, and a Joint Committee 
of the Societies of Public Analysts and Chemical Industry. At the Govern- 
ment Laboratory an electrolytic apparatus was devised in which the use 
of zinc for the production of hydrogen was not necessary. This apparatus 
has been modified by replacement of the expensive platinum cathode 
originally used by lead coated with mercury, which has been found to give 
very satisfactory results. 

It was not until the end of 1916 when the war had continued for more 
than two years that the control of the food supply of the country passed 
into the hands of a ]\Iinistry of Food. In the meantime much work of a 
scientific nature had been done in the way of endeavouring to educate the 
people on food values. A pioneer in this direction was Professor W. H. 
Thompson, who occupied the Chair of Physiology in Trinity College, Dublin, 
and who became later Scientific Adviser to the Ministry of Food. He was 
unfortunately lost in the sinking of the Irish mail boat in which he was a 
passenger. Thompson communicated to the Royal Dublin Society early 
in 1915 an important paper deahng with the energy value and chemical 
constitution of foods, subsequently published as a pamphlet under the 
title of ' The Food Value of Great Britain's Food Supply.' The question 
of the food supply of the United Kingdom was receiving attention in 1916 
from a Committee of the Royal Society which included among its members 
distinguished chemists, and at the request of the Board of Trade the 
Committee drew up a report on the food supply in which much of Thomp- 
son's work was incorporated. It is interesting to note that in the main the 
values given by Atwater in the ' Chemical Composition of American Food 

"*"* Illustrating Address on Chemistry and the Stale, Section B. 











Board of Agriculture 




[Lawes] — i 
[Gilbert] — 


Lectured on 




Assistance — i 

from ■ 

Development ■ 

Commission i 




Laboratory — 

Referee on 

Composition of 

Fertilisers and 
Feeding Stuffs 

Department of Scientific and 
Industrial Research 

— Boards I— Research t— Assisted 

1 Associations ■ Academic 

1 1 Research 
1 1 
■ 1 

Thick line indicates definite laboratory equipment. 

ilion, Hud Repurt, Tanmio, 1624. lUwiiaiinQ AdJrcH cm OAtmurfy and ihi Slau, Stclim B. 





^1 > !"' 







Materials ' were followed in the calculations. There can be little doubt 
that the decision of the Government to recover a larger proportion of the 
grain for human food in milling wheat, and to restrict the use in brewing 
and distilling of materials capable of use as food, arose from the suggestions 
put forward by this Scientific Committee. 

The chemical examination of the enormous quantities of food, together 
with the inspection of the packing and the testing of materials used for 
the purpose, forwarded overseas from this country for the Army in the 
war was entrusted to the Government Laboratory. Chemists were estab- 
lished at the various receiving depots, and all goods delivered by contractors 
were inspected, and, if considered necessary, sampled and analysed as to 
their conformity with specification. The chemist reported upon each 
delivery before the Army authorities proceeded to issue it. 

The Medical Research Coimcil, now under a Committee of the Privy 
Council, deals with subjects coming within the province of biochemistry, 
and the organic chemist has here an opportunity for preparing substances 
which the knowledge now available indicates as likely to be of value in 
combating, for example, diseases due to parasites in the bloodstream. 


The connection of the State Avith scientific agriculture goes back to the 
beginning of the nineteenth century. The period from 1770 to 1820 was 
one of great activity in agricultural development. It was then that several 
of the oldest agricultural societies were formed, and the Chair of Agriculture 
and Rural Economy founded in Edinburgh UniversitJ^ 

The first Board of Agriculture was formed in 1793, and it was to this 
Board that Humphry Davy, himself one of its members, dehvered during 
the years 1802-1812 the courses of lectures which were afterwards published 
under the title of the ' Elements of Agricultural Chemistry.' Davy in his 
introductory remarks dealing with the object of the lectures sets out 
clearly what he understood by Agricultural Chemistry — it ' has for its 
object all those changes in the arrangement of matter connected with the 
growth and nourishment of plants ; the comparative values of their 
produce as food ; the constitution of soils ; the manner in which lands 
are enriched by manure, or rendered fertile by the different processes of 
cultivation.' This statement sets forth the position to-day, and in the 
progress that has been made towards the attainment of these objects the 
chemist has j^layed an important part. 

Although Davy quotes the results of his chemical work on a series of 
grasses, no great advance was made for many years, and when it did come 
it was at the instance of private enterprise. To John Bennet Lawes, the 
founder of Rothamsted, is due the initiation of experiments which began 
in 1834 and have continued uninterruptedly until to-day. Joseph Henry 
Gilbert joined Lawes in 1843, and the association of the two was not broken 
until Lawes' death in 1900. The cost of this experimental station was 
borne entirely by funds supplied by Lawes. Whtn Gilbert died in 1901, 
Sir A. D. Hall became director, and he was succeeded in 1912 by the present 
director. Sir John Russell. 

The next experimental station in England was that founded by the 
Royal Agricultural Society on the Duke of Bedford's estate at Woburn 


under the direction of Dr. A. Voelcker, and now carried on by his son 
Dr. J. A. Voelcker. The Royal Agricultural College at Cirencester was 
founded in 1845. 

The development of the scientific study of agriculture was thus left 
largely to such institutions as that of Rothamsted, and to certain agricul- 
tural colleges which did not receive State aid. 

The first legislative action on behalf of agriculture with which the chemist 
was concerned was an Act for the protection of the agriculturist against 
fraud from the purchase of inferior or worthless manures and feeding stuffs. 
By the Fertilisers and Feeding Stuffs Act of 1893, superseded by the Act 
of 1906, the seller of artificial fertilisers and certain classes of artificially 
prepared feeding stuffs was compelled to give with the goods an invoice 
guaranteeing the percentages of specified constituents on which the value 
of the article depended, and county authorities were required to appoint 
agricultural analysts for the purpose of checking the statements on the 
invoice by analysis of samples. The Board of Agriculture also appointed 
a chief analyst who was required to analyse the reserved samples in cases 
where discrepancies were of such a nature as to lead to the possibility of 
proceedings in Court. 

It will thus be seen that, with the exception of the encouragement 
given to the work of Davy, the first State action was not towards develop- 
ment of agriculture, but for the repression of fraud. There were, however, 
movements from time to time in the direction of scientific inquiry into 
problems connected with agriculture, such as an investigation into the 
effect of food and breed on milk, and an inquiry into the efficiency of sheep 
dips, with both of which the Government Laboratory was closely associated. 

No systematic educational work in scientific agriculture was attempted 
in Great Britain before 1909, when an Act was passed allocating annually 
the sum of £500,000 for ' aiding and developing agriculture and rural indus- 
tries by promoting scientific research, instruction and experiments in the 
science, methods and practice of agriculture (including the provision of 
farm institutes).' Under this Act, a system of agricultural research was 
framed, based on university and on research institutions like Rothamsted, 
and Hnked up with the agricultural colleges. The scheme formulated 
enabled the Development Commissioners appointed under the Act to 
form new institutes as well as to extend the existing ones. Rothamsted 
was largely extended, and increased facilities afforded for work on Plant 
Physiology (Imperial College), Plant Breeding (Cambridge University), 
Animal Nutrition (Cambridge), Dairying (Reading), Animal Pathology 
(Royal Veterinary College), and on similar subjects. In many of these the 
chemist was essential. Another part of the scheme was the foundation of 
scholarships awarded to selected graduates of universities, tenable for a 
three-year course of research. In certain selected teaching institutions 
technical advisers for farmers were appointed, and researches not capable 
of being pursued at an institute were maintained elsewhere. 

The provision of this scientific work for the benefit of agriculture is 
carried out by the Commissioners through the medium of the Board of 
Agriculture, with which policy is discussed and details arranged. It 
represents the first co-ordinated attempt by the State in the United King- 
dom to secure a comprehensive scientific study of the problems of agri- 
culture, and the fiirst systematic endeavour to apply scientific method to 


the development of agriculture. Results followed at once, and as an 
illustration it may be pointed out that in the eight years from 1912 to 1920 
Rothamsted issued, in spite of the adverse effects of the war, 75 scientific 
papers, published eight books, and contributed numerous articles for 
farmers and teachers, and the Cambridge Animal Nutrition Station also 
published 60 papers in the same period. Other institutes also contributed 
to knowledge on this subject. 

During the war, agriculture in this country was affected in several ways 
— for example, by (1) shortage of the usual feeding stuff's for cattle, and 
(2) shortage of fertilisers, particularly potash and nitrogen, both as nitrates 
and ammonium salts. At the same time there was a demand for an in- 
creased production owing to the diminished supplies of essential foods from 

The attention of chemists was directed to these points. Fortunately 
the research institutes provided by the funds of the Development Act 
referred to above were in existence and available for making investigations. 
Thus the staff at Rothamsted under Russell gave special attention to the 
shortage of manures and prepared monthly notes for the guidance of 
farmers, while the Animal Nutrition Institute at Cambridge under T. B. 
Wood provided monthly notes on the uses of available feeding stuffs. 
In the latter part of the war, conferences were held weekly at the Food 
Production Department in which research workers from the institutes 
took part. These meetings had such value that the Ministry of Agriculture 
and Fisheries have now constituted an Advisory Council in Agricultural 
Research at which the directors of the institutes meet periodically to review 
the progress being made. 

When the war-time requirements of nitrogenous fertilisers are considered, 
it is significant that the production of nitrogen in the form of ammonia 
showed no increase in the first years of the war, and only a six per cent, 
increase in 1917 over 1913. The restriction of nitrate supplies for muni- 
tions caused a greater demand for nitrogen in the form of ammonia, and 
it may be expected that in the future even larger quantities will be needed. 
The Nitrogen Products Committee estimated that the possible demand in 
the near future for artificial nitrogenous fertilisers for the United Kingdom 
would be 100,000 tons of nitrogen, or four times the quantity used in 1913. 

Of the fertiliser ammonium sulphate we produced before the war five 
times as much as we required for our own use, but we imported also over 
100,000 tons a year of sodium nitrate from Chile. During the war the 
importation of this salt was quadrupled and nearly all was taken up for 
munitions, being converted into nitric acid for the purpose of nitrating 
glycerine, cotton, toluene and phenol, and made into ammonium nitrate 
for the explosive amatol. All our explosives therefore depended on the 
importation of Chile saltpetre, a condition of affairs which gave rise to great 
anxiety, especially at the height of the submarine menace. Although we 
still had sufficient ammonia, there was no plant available for oxidising it 
to give the nitric acid required. As no sodium nitrate could be spared for 
agriculture, its place was taken by ammonium sulphate, of which increas- 
ing quantities were used for manuring the soil to obtain increased produc- 
tivity. At the same time this salt was being increasingly used for making 
ammonium nitrate, so that the time approached when, in place of the ample 
margin before the war, a shortage of ammonia was in sight. 


The claim of munitions on sulphuric acid also materially reduced the 
quantity of ammonium sulphate as well as of superphosphate by about 
40 per cent., and chemists had to devise means for using nitre-cake in its 
place in the manufacture of these fertilisers. 

Anxiety as to the want of capacity of the country for fixation of atmo- 
spheric nitrogen had led in June 1916 to the foundation of the Nitrogen 
Products Committee, the results of whose labours will be found in a massive 
Blue Book full of information on statistics, on processes, and on the com- 
parative merits of methods for developing power. A staff of chemists and 
physicists attached to the laboratory of this Committee were actively 
engaged on investigations on the conditions of manufacture of ammonia 
by the Haber process, as well as in determining the physico-chemical 
constants of the gases involved. Much valuable work was accomplished 
both on the combination of hydrogen and nitrogen and also on the oxidation 
of the product to nitric acid, so that the Committee was able to recommend 
the erection of a trial plant in February 1917, and by October of that year 
the Department of Explosives Supply recommended the process worked 
out for adoption in a national factory, and a start had been made towards 
its erection at the end of the war. 

This project was taken over by Synthetic Ammonia and Nitrates, Ltd., 
which has continued the research work and erected the large-scale plant. 
It is satisfactory to be able to announce that, instead of being about the 
only great nation not engaged in the fijxation of nitrogen from the air, we 
have now in Great Britain a plant producing at the moment 150 tons of 
synthetic ammonia a week. From the point of view of agriculture as well 
as of national defence, this cannot fail to afford a fresh, if somewhat 
delayed, confidence. 

The shortage of potash supplies was apparent soon after war broke out, 
since nearly all potash came from Germany. Attention was immediately 
drawn to other possible sources of supply and to means whereby the potash 
in stable combination in the soil might be made available. Russell at once 
called attention to the potash salts in the ash of seaweed, bracken, hedge- 
clippings, wood-waste, and similar substances, and advised as to the best 
methods for utilising them. He also advised the use of lime, and in certain 
circumstances of sodium salts, whereby potash in the felspars and clays 
became available. 

Numerous suggestions put forward as to possible sources of supply of 
potash were inquired into. In one interesting case, where a small-scale 
plant was put into operation under the supervision of the Government 
Laboratory, a good yield of potash was obtained from felspar, but the 
process involved the production as a by-product of so large a quantity of 
an inferior quality of cement that unless a market could be obtained for 
this there was no possibiUty of working the process successfully. 

A source of supply that was used to a certain extent was the flue-dust of 
furnaces, which was found to contain a fair though variable quantity of 
potash. Considerable developments were made by Mr. Kenneth Chance, 
of the British Cyanides Co., in the direction of obtaining from the ores 
dealt with in the United Kingdom a large supply of potash, and an 
extensive scheme of operation was contemplated before the Armistice. 

Another direction in which supplies became restricted was in respect of 
phosphatic manures. Importation of bones, mineral phosphates, and guanos, 

r>— CHEMISTRY. 7 7 

owing to war conditions, could not be maintained, and, owing to the demand 
for sulphuric acid for essential munitions of war, the supply for manufac- 
ture of superphosphate was strictly limited. Hence attention was directed 
to the examination of the results obtained by using finely ground natural 
mineral phosphates and basic slag. These insoluble phosphates were 
found to possess a considerably greater value as fertilisers than they had 
been given credit for. 

The shortage of food-stuffs for cattle arose partly from decreased imports, 
particularly of linseed, cotton seed, and grain, and partly from causes within 
the country, as for example the dilution of flour with maize and other cereals 
and the milling of the grain to obtain an increased percentage of flour for 
human food, whereby the quantity of milling offals was reduced. The 
attention of chemists was at once directed to the question of new or hitherto 
little-used food-stuffs. For some years prior to the war the importation 
into Continental countries, particularly Germany and France, of valuable 
oil-seeds had been rapidly increasing, thus providing oils for margarine 
manufacture and valuable cakes and meals as food for cattle. The case 
of palm-kernels, a valuable source of oil and cake, is a striking one, for 
British West Africa exported before the war about 230,000 tons, of which 
35,000 tons came to England and 181,000 tons to Germany, and a similar 
condition applied to copra, earth-nuts, and sesame seed. These and many 
other seeds began to be diverted to the British market, and the cakes or 
meals, after examination of feeding value, formed a useful addition to the 
food supplies, as was illustrated by the great increase in the manufacture 
of margarine. 

Home supplies were also explored, materials which had hitherto been 
discarded were tried, and waste material from a variety of sources was 
utilised. In all this the work of the chemist was essential. The ascer- 
taining of the composition of the material, of the dige-stibility coefficients 
of the various constituents, and of the feeding value of the material was 
the contribution of the chemist to this great problem of the nation. 

Since many of the war-time expedients mentioned above were of a 
makeshift character, it is not surprising that they did not survive when 
normal economic conditions arose. Thus, when sulphuric acid again 
became available, the troublesome use of nitre-cake was abandoned and 
blast-furnace flue-dust was no longer collected. It was disappointing 
that the nitrogen fixed in the large surplus stocks of explosives, both in 
the form of nitric esters and of nitrogen compounds, could not profitably 
be utilised. Many of the difficulties were overcome in the case of the nitric 
esters by the application of a process of alkaline hydrolysis, but the 
attempt was abandoned on account of the difficulties which arose during 
process in freeing the product from poisonous impurities and in putting 
it on an economic basis. 

The war-emergency work has had some lasting effects, of which may be 
mentioned the development of a process for making ' synthetic farmyard 
manure,' the increased use of basic slag as a phosphatic fertiliser, and the 
increased attention that is being devoted to the newer nitrogenous fertilisers, 
more particularly those produced by fixation of atmospheric nitrogen. 

The lessons of the war have not, however, been entirely lost. The last 
report of the Development Commissioners, for the year ended 31st March, 
1923, shows advance in every direction. In addition to the sum available 


from the Development Fund of the Act of 1909, it was possible to make 
increased grants owing to the money received under the Corn Production 
Acts (Repeal) Act, 1921. The special fund enabled grants to be made for 
additional research, as, for example, the extension of the advisory scheme 
in connection with agricultural research, the provision of scholarships for 
children of agricultural workers, and the endowment of a Chair in Animal 
Pathology at Cambridge. In order to prevent overlapping and to secure 
co-ordination, the Development Commissioners are working in consultation 
with the Medical Research Council and the Department of Scientific and 
Industrial Research. 

It may be said that the greater part of the work on agricultural chemis- 
try since the war has been of a fundamental nature, the results of which 
have not yet become capable of translation into agricultural practice, 
although they may be expected to exert ultimately a powerful influence 
on farming. 

Other Activities, 

In addition to the activities that have been grouped under the respec- 
tive headings, there are many others bearing on State problems which 
have occupied the attention of chemists. 

Thus, expeditions, such as that of the Challenger, have been fruitful in 
results of chemical work. The investigations of Dittmar on the composi- 
tion of sea-water and of Murray on mineral phosphates may be recalled 
in this connection. 

For data on the chemical composition of rocks the Geological Survey 
is indebted to the work of Percy, Dick, and Pollard, and for work on the 
formation of igneous rocks to Teale, Harker, and Flett. The remarkable 
experiments of Sir John Hall on rock-formation at the beginning of the 
nineteenth century have been described in a recent British Association 
address. On several occasions the choice of building-stone, especially for 
the Houses of Parliament, has been before groups of geologists and chemists, 
especially with respect to the action of atmospheric impurities, and although 
the causes of decay are fairly clear, its arrest still forms a difficult problem. 

The difficulties in selecting colours sufficiently fugitive to prevent the 
removal of obliteration marks from postage and fiscal stamps were to a 
large extent solved by the activities of Warren de la Rue. 

Investigations on such matters as the above for various Departments 
of State form part of the work of the Government Laboratory, which in 
addition, during the war, had to advise concerning the conservation of 
materials, the control of imports and exports by the War Trade Depart- 
ment, and on the nature of contraband goods. 

Organised Applied Research. 

In the middle of 1915, at a time when our shortage of many essential 
materials brought out the need for the application of more scientific 
methods to our industries, if we were to succeed in competition with other 
countries after the war, the Department of Scientific and Industrial 
Research was founded. It set out to assist firms in an industry to co- 
operate with one another and employ a staff of scientific men to solve 
their problems and develop their industry, to assist other Government 
Departments desirous of having investigations carried out, to organise 


research into problems of practical utility of wide importance, and to 
foster the prosecution of researches in pure science. With the exception 
of the last, these aims can be considered as coming under the designation 
of organised applied research. The Department has always strongly 
insisted that it is this type of work only that it seeks to organise, the 
assisted worker in pure research being left entirely free to follow his bent. 

As regards scientific policy, the Minister in charge of the Department 
is advised directly by a Council of independent scientific men, and these 
are represented also on the various Boards and Committees entrusted with 
the supervision of such investigations as are directed by the Department 

Research Associations. — From the success attending applications of 
scientific research in military and industrial problems during the war, the 
lesson was drawn that our industries in peace-time should be infused with 
fresh and more vigorous life by methods which had proved their worth at 
our time of need. Foresight in these matters was necessary, since it 
behoved Great Britain, no longer with the industrial world at its feet, to 
make the utmost use of its resources, by adopting the methods that were 
most efficient and solidly based on science, in order to produce material 
that would maintain the tradition of the excellence of British goods. 
While it was recognised that the most powerful chemical industries main- 
tained efficient research staffs, it was decided to encourage separate 
industries to organise themselves for the co-operative prosecution of 
research. To the associations erected under this scheme grants, for a 
term of years only, and usually on a pound-for-pound basis, are made from 
a fund of a million pounds voted by Parliament in order to demonstrate 
to the industries the advantage of investigating their own technical 
problems, for it was recognised that many industries would have to carry 
out research themselves before they could properly appreciate its 

In its last published Report the Department remarks on the continuance 
of these grants to the associations beyond the originally intended period 
of five years, as this period has proved insufficiently long for the equipment 
of laboratories and the effective launching of important investigations, 
especially during a time of industrial depression. 

A very wide field is covered by the research associations. Among 
those that have been set up in which chemistry is important are associa- 
tions for the textile industries, for rubber, leather, and shale oil, for flour 
and sugar, for non-ferrous metals, cast iron, glass, refractories, and Portland 
cement, and for scientific instruments and the photographic industry. 

As the results obtained by the associations are 2:)rimarily for the benefit 
of their constituent members, the onlooker has a chance of gauging the 
chemical work carried on only from the communications which, following 
an enlightened policy, the management of some of them permits to be 
published ; and as many of these are contributions to ' pure ' chemistry, 
an example is afforded of the opportunity as well as of the necessity for 
work of this kind in the case of investigations undertaken primarily for an 
industrial purpose. 

It would be impossible to review the work of the research associations 
for all these industries, even if the data were available, and so reference 
will be made only to some of their publications, including those of the 


group which is concerned with the textile fibres, cotton, flax, wool, and silk, 
as the work published presents many interesting features. Thus there 
are being studied the products of the hydrolysis of cotton, with an obvious 
bearing on the constitution of cellulose, the chemical constituents of 
cotton waxes, and the action of micro-organisms on cotton fibres and 
fabrics. Flax, hemp, and ramie fibres are being investigated as to their 
distinguishing characteristics and behaviour with reagents that affect 
their lustre and absorption of dyes. Wool has been found to have a 
selective action, whereby it absorbs the alkali from the soap used in 
scouring, and methods have been evolved for accurately following the 
action in practice. Similarly with silk, a systematic study is being made 
of the action of acids and alkalies on the components of this fibre. In the 
respective laboratories the chemical and physical properties of each of 
these fibres are being studied and correlated for the purpose of explaining, 
for example, their strength and lustre, and at a recent meeting of the 
Faraday Society the methods and results of workers in all these fibres 
were reviewed in a General Discussion. 

A close scientific scrutiny is being applied to the tanning of leather, 
and the chemical and physical changes involved, together with a bacterio- 
logical study of the process. Equally important for this industry and for 
that of making photographic plates is the study of gelatin, whose chemical 
and physical properties are being elucidated, while work of benefit to pure 
science has been published on the effect of light on the photographic 

The study of the chemistry of glass and the physical properties 
associated with changes in its composition is another example of work 
that has been reported in the literature for improvement of an industry. 

The record, as has been stated, must be incomplete, but the subjects 
mentioned present the appearance of being valuable in the scientific 
study of material and process, and can scarcely fail to lead to the better- 
ment of the respective industries. 

Boards. — The Boards and Committees under the Department may be 
broadly divided into those which undertake the investigation of work of 
national importance, and those which undertake work of specific importance 
to Government Departments and correlate the scientific work that these 
carry out. 

A large amount of chemical work is carried out by these Boards. The 
Departmental Eesearch Boards and Committees dealing with chemical 
subjects are concerned with the cause of the deterioration of fabrics by 
organisms and light, and their fireproofing ; with the changes that food 
undergoes under varying conditions of storage, and the constitution of 
fats ; with the chemistry of the treatment of timber ; with the survey of 
our coal resources and the economic usage of coal ; with the production 
of alcohol and liquid fuel from waste vegetable matter ; with the chemical 
aspects of the problems of adhesion, lubrication, restoration of museum 
exhibits ; with building materials, paints, and the jjreservation of stone, 
and with the properties of several of the minor metals. For subjects of 
the magnitude and importance of some of these, staff and equipment have 
in several instances been provided on a considerable scale, and a growing 
number of monographs and communications to the literature issues from 
the respective Boards, 


The Co-ordinating Board for Chemistry, like the similar Boards for 
other sciences, was founded for the purpose of securing interchange of 
information among Government technical establishments, seeing that 
outside interests are informed, when this is practicable, and arranging for 
researches not otherwise provided for. The Board carries out these duties 
in consultation with representatives of the Fighting Services and of other 
Government Departments materially affected, and with independent 
chemists, when departmental schemes of work are reviewed in the light of 
information that may be in the possession of any of the members of the 
Board. To this Board are referred questions of wider importance than 
are within the purview of any one Department, and it keeps under its 
consideration the development of the natural resources of the country. 
With further facilities for undertaking investigations, it will be in the 
position to extend such work and to arrange for subjects not otherwise 
provided for, as well as for those at present under investigation. 

Assisted General Research. 

Apart from the indirect help afforded to the universities by means of 
Government grants, direct assistance is given by the Department of 
Scientific and Industrial Research to research workers who may be 
students, or independent workers, and to important pieces of pure research. 
To these grants no conditions are attached ; they are given for the exten- 
sion of knowledge. 

One of the objects of these grants is to encourage the supply of highly 
trained scientific research workers to meet the growing needs of the Govern- 
ment, the industries of the country, and indeed of the Empire. The lack 
of such was felt acutely during the war, although now, for chemists with 
the usual qualification at any rate, the conditions have changed. 

Students are given grants on the recommendation of their professor that 
they are a type likely to be greatly benefited by spending two years at 
research work after taking their degree. In this case the award is for 
promise and not for achievement, and the hope is entertained that the 
necessity for these grants will gradually disappear when university finance 
is on a sounder basis. 

Grants are given to independent workers who have shown their capacity 
for research, and who are handicapped by lack of facilities which they may 
not be able to secure from private or other sources. Further, in the case 
of work of unusual importance, very substantial financial assistance may 
be given when it appears desirable. 

In this way comes recognition of the national importance of the highest 
type of scientific work, and to this, of course, no conditions are imposed 
as to the lines on which it should be carried out. 





The State's appeal to chemistry has developed through the gradual 
recognition of the need for the application of that science to matters relating 
to its preservation, its currency, its financial support, its health, its food 
supply, its industries, and finally to academic science. A chart illustrating 
this development historically is appended to this address. 

In the course of this development, advantage has been taken, if some- 
times tardily, of the general advance in chemical knowledge, and frequent 
recourse has been had to the advice of well-known chemists of the day, 
and collectively of the Royal Society ; thus for various purposes the 
following chemists, as officials or consultants, have in the past afforded 
assistance in the solution of specific problems referred to them, or by taking 
part in Commissions : Boyle, Newton, Davy, Faraday, Daniell, Graham, 
Hofmann, Redwood, Abel, Roberts-Austen, Percy, Dupre, Playfair, 
Frankland, Ramsay and Dewar. If has happened in several instances 
that as a result of these Commissions and references to chemists some 
definite chemical activity of the State has emerged. 

It will be convenient in this summary to review the State's chemical 
activities before, during, and after the war. 

Before the war. 

Defence. — For its defence, establishments for the production of explo- 
sives were early maintained, and when this ultimately took the form of 
a chemical manufacture the Government factory took the lead in devising 
efficient processes, while from the various State research establishments 
has issued during the last fifty years an important body of original 
contributions to the theory of explosives and to the knowledge of their 

Metallurgy. — The metallurgical progress of the country has always been 
a concern of the State by reason of its application to defence by land and 
sea, and close touch has been maintained with successive developments in 
the manufacture and use of cast-iron, wrought-iron, steel and non-ferrous 
alloys. While the main advances in process have been made in the great 
iron and steel works, material contributions to knowledge in this sphere 
have been made by chemists in the Government service. 

Revenue. — For its revenue, imposts were applied in early times, but 
with great uncertainty, until the charge was put on a scientific basis. Very 
accurate tables for the strength of alcohol were worked out under the 
supervision of the Royal Society at the end of the eighteenth century, 
to be superseded by revised ones issued only a few years ago, when, in 
addition, new tables were issued also by the Government Laboratory, 
for determining the gravity of worts before fermentation. The question 
of rendering alcohol unpotable, but still useful for industrial purposes, 
has occupied much attention. As some misapprehension still exists as to 
the availability of alcohol for industrial purposes, a statement has been 
incl ded in which the main facilities are indicated. It was on account 
of the necessity for safeguarding the revenue that the Government Labora- 
tory was primarily erected, although it now performs chemical work for 
all State Departments. 


Health. — The three main steps with regard to public health and sanita- 
tion in this period were the forcing of these questions into prominence by 
Playfair, with the consequent Commissions and legislation leading to the 
formation of the Local Government Board and its successor, the Ministry 
of Health, which has many varied activities in preserving purity of air 
and water and protecting the workman in dangerous trades ; secondly, 
the determination of standards for a safe water supply by the pioneering 
work of Frankland ; and thirdly, the appointment of public analysts by 
the local authorities, with the Government Laboratory as referee, for safe- 
guarding the supply of food. 

Agriculture. — Science was being applied to agriculture about the end 
of the eighteenth century, and at the beginning of the next Davy did 
pioneering chemical work for the Board of Agriculture. Private endeavour 
is responsible for the next development. State action being limited to the 
prevention of fraud in the sale of fertilisers and feeding stufis. In 1909, 
however, the annual allocation of a sum of money to the Development 
Commission for the advancement of agriculture stimulated research in a 
large number of institutions engaged in the scientific study of problems 
in which chemistry plays an important part. 

Other Activities. — In addition to the chemical work reviewed in the 
foregoing sections, there is a variety of subjects connected with State 
Departments to which chemists have contributed, such as the composition 
of the sea, and the composition and physical chemistry of rocks and build- 
ing-stone. At the Government Laboratory a large number of investiga- 
tions have been conducted on matters directly referred from Government 

During the war. 

In all the activities described, the war requisitioned the work of the 
chemist, but, naturally, predominantly to meet the demands of active 

Defence. — The attention that had been bestowed on the subject of 
propellants enabled expansion to take place with no important alteration 
in the technique of their manufacture, to which was adapted a new type 
of cordite, ultimately made on the largest scale, without using an imported 
solvent. For high explosives we were in much worse case, as these had 
not been made by the Government, and were manufactured in Great 
Britain only in small quantity. Their study at Woolwich led to a rapid 
evolution of new processes, substances, and methods of use. Thus a method 
was worked out for the manufacture of trinitrotoluene, and to save this 
substance a new high explosive, amatol, devised. This explosive, consist- 
ing of ammonium nitrate and trinitrotoluene, passed exhaustive trials and 
was ultimately produced at the rate of 4,000 tons a week. The production 
of the ammonium nitrate for the mixture was in itself a stupendous under- 
taking, and the methods of filling the explosive into shell and other muni- 
tions gave rise to much ingenuity. In the Research Department, Woolwich, 
the number of qualified chemists engaged in the study of explosives in 
all their aspects ultimately exceeded a hundred, while for manufacture and 
inspection over a thousand were employed. The ideal set before himself 
by Lord Moulton in 1914, to produce nothing less than the maximum of 

G 2 


explosives of which the country was capable, was realised, and they assumed 
a quality and character that caused them to be copied by our AUies, and 
in reliability proved themselves superior to those of the enemy. 

Starting unprepared, and without the advantage of a well-developed 
fine-chemical industry, we were able ultimately to make a reply in the field 
of chemical warfare that was rapidly becoming more and more effective ; 
at the same time, by study and often self-sacrificing experiment, protecting 
the soldier by the development of very efiicient respirators. In this 
connection and in that of explosives nearly every professor of chemistry 
in the country and many from beyond the sea were engaged. 

Metallurgy. — The enormous demand for metals for munitions and count- 
less other war requirements led to an unprecedented concentration of the 
metallurgical industries on the needs of the State, and to an equal concen- 
tration of metallurgical science on investigation devoted to improvement 
in quahty of materials for new and special war purposes. The work of the 
Aircraft Production Department, aided by many metallurgists and engi- 
neers, on alloy steels, of the National Physical Laboratory on aluminium 
alloys, and of the Metallurgical Branch of the Research Department, 
Woolwich, on the heat-treatment of heavy forgings and on the drawing of 
brass, is typical of the successful effort made in every quarter. The know- 
ledge thus gained was disseminated in the form of specifications, instruc- 
tions, and reports, and has had a great and permanent effect on manufac- 

Health. — A committee of the Royal Society had been studying food 
values, and were able to afford the Food Controller, when he took office, 
valuable data bearing on the rationing of food. They had considered 
subjects which shortly became of much importance, such as a better 
recovery of flour in milhng wheat. The chemical examination of the food 
for the Army in the war, carried out by the Government Laboratory, 
employed a large staff of chemists. For the supply of many fine-chemical 
substitutes used in medicine and surgery, formerly imported from abroad, 
such provisional arrangements had to be made as the organisation of a 
large number of university laboratories on a semi-manufacturing basis. 

Agriculture. — Effects on agriculture during the war were shortage of 
the usual feeding stuffs for cattle and of fertihsers. The chemists stationed 
at Rothamsted gave special attention to the shortage of manures and 
prepared instructions for the guidance of farmers ; and several sources 
of supply of potash were exploited, including kelp, felspar, and the flue- 
dust of furnaces. As sulphuric acid was required for explosive work, 
fine grinding of phosphates and basic slag was found to be more efficient 
than was expected. Shortage also directed the attention of chemists to 
the use of little-known food-stuffs, especially for cattle, and the information 
gained as to their feeding value was important. 

Other Activities. — In many other activities in connection with the war 
chemists were directly involved, such as in affording advice on the conser- 
vation of materials, on the numerous questions arising from the operations 
of the War Trade Department, on the restriction of imports and exports, 
and on matters of contraband. 


After the war. 

The magnitude of the chemical effort, it can be claimed, was a factor 
in winning the war which must be reckoned as of importance only second 
to that of the bravery of our forces in the field. But it has left a lasting 
mark, and given to chemistry a value which, were it not for the rapidity 
with which the achievements of science are forgotten, ought to keep before 
the pubUc its connection with almost every phase of activity. 

Defence. — To take our subjects in the same order, we may consider 
some of the effects of the energy spent on the production of munitions. The 
intensive study of explosives and of other chemical substances used in the 
war has led to a more complete knowledge of their chemistry, their physical 
and explosive properties, and has advanced chemical theory. These 
advantages are not of military importance only, but are reflected in the 
production of trade explosives. The collected records of the Department 
of Explosives Supply afford examples of treatment of many problems of 
interest to the general chemical technologist, and not only to the explo- 
sives expert. 

A further benefit was reaped by chemists in every position, from the 
Professor to the youngest graduate, coming into direct contact with manu- 
facturing methods and thus gaining insight into the applications of their 
science. While it is true that the opportunity came to few of these to take 
part in the design of plant and primary choice of process, nevertheless the 
experience was a novel one, as it led them into the field of technology, and 
cannot fail to have widened their outlook. It became apparent that there 
was a shortage of a type of chemist which had been developed in Germany, 
skilled in the transference of the chemical process from the laboratory to 
the works scale in the largest enterprises. A chemist of this type is one 
who, besides having a sound knowledge of chemistry and physics, has had 
experience in the materials of construction used on the large scale and in the 
operation of the usual types of plant for carrying out the operations of 
chemical manufacture, and who is capable of working out flow-sheets 
illustrating the process, and operating plant with every regard to economy. 
The need for instruction in such subjects had been borne in on men like 
the late Lord Moulton, and as a direct result of the war-time experience 
of our deficiencies in this direction has arisen the movement for erecting 
Chairs of Chemical Engineering in some of our universities. It is to be 
expected that from these schools, especially where the instruction is super- 
imposed upon a full graduate course, will emanate men who will lead the 
way in the application of academic science to industry. 

Metallurgy. — While the interest of metallurgical science in war material 
has fortunately fallen to a peace-time level, State participation in the 
support of scientific research remains far greater than before the war. 
In metallurgy it is exercised through the Department of Scientific and 
Industrial Research, with its organisations of the National Physical 
Laboratory and the Industrial Research Associations, as, for example, 
those dealing with the non-ferrous metals and with cast-iron. The State 
also continues to maintain efficient research estabhshments for the Fighting 
Services, but it is significant that the largest of these is xmdertaking indus- 
trial metallurgical research on a considerable scale, for the benefit of the 


brass and othier industries. State support and encouragement are un- 
doubtedly powerful factors in the rapid progress now taking place in 
every branch of metallurgical science in this country, and there is scarcely 
any related industry which can fail to benefit. 

Revenue. — Since the war the principal matters affecting the revenue 
are the higher duties, which have rendered necessary a further deuaturation 
of alcohol. Improved facilities have been granted for the use of alcohol 
for scientific purposes and in industry ; regulations have been formulated 
for the use of power alcohol, and duties have been established on imported 
fine chemicals and synthetic dyestufis. 

Health. — The food shortage during the war called attention to the nature 
and quantity oiour food supplies, and led to further investigations being 
imdertaken by the Department of Scientific and Industrial Research on 
food preservation and storage. Activity is also shown by the appointment 
of Committees which are working on the subject of preservatives and colour- 
ing matter in food, and on the pollution of rivers by sewage and trade 
effluents. A great field is open in the co-operation of chemistry with 
medicine in the discovery of substances suitable for the treatment of the 
numerous diseases now traced to parasites in the blood. 

Agriculture. — So far as fertilisers are concerned, the lack of a supply of 
fixed nitrogen from the air which obtained throughout the war has now 
been rectified, and Great Britain for the first time is no longer exceptional 
among the nations by neglecting to provide itself with synthetic ammonia 
for agriculture and for munitions. Such war-time expedients as the use 
of nitre-cake instead of sulphuric acid for making ammonium sulphate 
and superphosphate and the recovery of potash from flue-dust have 
not survived, but there has been a gain in the further development of 
'synthetic farmyard manure' and the increased use of basic slag. The 
present activity in research in agricultural chemistry of a fundamental 
character is leading to a better understanding of problems of the soil and 
of plant and animal nutrition, and cannot fail to be of ultimate benefit 
to farming. 

Organised Applied Research and Assisted General Research. — Established 
during the war as a result of an appreciation of the contrast between 
the successful application of scientific method to military purposes and 
the want of such application to many of our manufactures, the Department 
of Scientific and Industrial Research has extended over a wide field. 
Its main activities have been sketched in the directions of State encourage- 
ment to industry to apply chemistry to its problems, of State investigation 
of vital problems beyond the sphere of private enterprise, and of assistance 
to workers in the purely academic field. In all these spheres activity is 
shown by the contributions to knowledge already forthcoming. 

In the expansion that has occurred in the chemical sections of State 
Departments since the war, it is interesting to note the increase in the 
number of chemists that are employed. As far as can be gathered, the 
number of chemists working in departments maintained whoUy by the 
State is 375 for the present year, compared with 150 in 1912, while in 


establishments to which the State affords partial support, such as those 
under the Development Commission and the Research Associations, the 
corresponding numbers are 150 and 50. In addition, grants are made to 
145 research students and to 11 independent research workers, involving 
a yearly sum of about £50,000. 

From the foregoing account of the connection of the Departments of 
State in the United Kingdom with chemistry, it is possible to trace a gradual 
development and ultimately a change in attitude, in passing through the 
stages of compulsion, expediency, and assistance. 

From motives of security the State was compelled to give heed to chemi- 
cal matters involved in its defence, such as those which appertained to muni- 
tions of war, including metals used in their manufacture ; it was constrained 
to uphold the standard of its currency; and it was obliged to secure a 
revenue. As a consequence, the first chemical departments were set up 
in connection with these activities, and from them have emanated notable 
additions to chemical knowledge, improvements in methods of manufacture, 
and specifications for Government requirements that have led to improved 
material becoming available for civilian use. Although mostly conducted 
with inadequate staff, the study of these questions, it can be claimed, 
proved of national advantage when the time of need arose. 

In the next stage, the public conscience having been awakened by the 
pioneering work of Playfair, it appeared expedient to safeguard health by 
attention to sanitation, and, as the quality of food was unsatisfactory, to 
set up a chemical control. Although a start was made by Davy, a member 
of the then Board of Agriculture, progress in this subject passed to private 
enterprise, and a century elapsed before direct assistance was afforded 
to this important matter. Out of these activities come our present system 
of supervision over the purity of air, water, and food, and also the recent 
progress made in the application of chemistry and physics to problems of 
the soil. 

The last and more recent stage is in the nature of a recognition that the 
State is under an obligation to assist science, and in this case the science 
of chemistry, on which so many important industries are based. It took 
the war to bring home the danger that, although the record of the country 
as regards discovery in pure science was unrivalled, its systematic application 
was too often left to other countries, with the result of lamentable short- 
ages during war and the risk of many industries being ineffective in peace. 
A measure of Government intervention and action appeared requisite, 
and research became the business of a Government Department. Outside 
of the great firms which maintain progressive chemical staffs, the firms in 
numerous industries have been encouraged and assisted to co-operate in 
the betterment of their manufactures by the application of the methods of 
science, and from these associations and the organisations deaUng with 
national problems begins to flow a stream of communications indicative 
of useful work accompHshed. Nor is the foundation of it all neglected, 
for encouragement is given to workers in the academic field to follow out 
their ideas, whithersoever they may lead them, in accordance with the 
truth that ' research in applied science might lead to reforms, but research 
in pure science leads to revolutions.' 


It is important to be able to record an advance in securing an inter- 
change of information among Government Departments, and between 
their work and that of the universities, a matter which before the war was 
unsatisfactory, as it was mainly personal and sporadic. 

And it is a hopeful sign also that, although the knowledge and apprecia- 
tion of the methods and capabilities of science are still generally wanting, 
there have been of late signs that these matters are coming to engage the 
attention of those who guide the policy of the State. 


Note to Address on following pages , by the President of the Section. — It was hoped 
that this Section would have been presided over by Dr, C. W. Andrews. He had 
indeed accepted the invitation of the Council to become President, but the state of 
his health later compelled him to resign. His untimely death has deprived our 
science of a widel3'^-travelled and most talented geologist, and a vertebrate 
palaeontologist of world-wide distinction. 




PROFESSOR W. W. WATTS, Sc.D., M.Sc, LL.D., V.P.G.S., F.R.S., 



Although Geology in the modern restricted sense of the word is over a 
century old, and possesses a flourishing family of descendant sciences, it is 
still possible to trace its immediate parentage and ancestry. The only 
begetter is unquestionably the mining industry, and it is to the ample 
exposure of rocks in mines, their condition and arrangement in the simpler 
mining districts, and the necessity for accurate knowledge of these districts 
with regard to composition, succession, and arrangement, that we owe the 
earliest detailed knowledge of the earth-crust in certain restricted localities. 

The other parent was of more advanced years, and may be described 
as ' insatiate curiosity ' : the natural instinct for observing and collecting 
odd and bizarre ' rarities ' found in excavations or seen m natural rock 
exposures. These fossils, using the word as then employed and not in the 
restricted sense now usual, naturally kindled interest by reason of their 
natural beauty, their regularity in shape, their properties, their likeness to, 
and yet their tantalising difference from, the appearance of living animals 
and plants. It was tempting to draw inferences from their occurrence and 
to explain them either by marvellous operations which fuller understanding 
of Nature had not then inhibited, or by means of catastrophic events like 
those familiar in the Mosaic cosmogony. 

Although much had been observed and thought out by his predecessors, 
it is to Werner that we owe the most successful generalisations in a mineral- 
bearing district ; generalisations which gained a wide influence owing to 
the enthusiasm and eloquence that attracted students from all over the 
world and imbued them with the desire to confirm and spread the Master's 
ideas. To Werner also is due a reaction from the fanciful speculations 
of preceding periods, with which he was so impatient that he proposed to 
drop the very term Geology and to substitute his own word ' Geognosy ' 
for it, a word intended by him to separate the knowable from the unknown. 

Probably there would have been less controversy between Neptunists 
and Plutonists had Werner committed more of his work to writing, and 
not left us dependent on his pupils for their versions of his views. But 
it is a curious fact, and one probably not dissociated from a geologist's 
devotion to field study, that many of those who have made great advances 
have either disliked the act of writing or have been unfortunate in the 
style of their written work. It will be suflicient to couple with Werner 
in this respect such names as William Smith, Sedgwick, and even Hutton, 
not to mention those of more recent geologists. It has not been from 
Smith alone that views and conclusions have had to be extracted, almost 
by force, and committed to writing by faithful devotees. 


Yet, after all, this failing has not been without its advantages. The 
joy of such men is in discovery, and they are happy and contented when, 
but only when, they feel perfect confidence in their conclusions. If their 
results then get published it is with an authority and finality denied to 
lesser men. In the progress of their work they are apt, as in fact all of 
them did, to infect their friends and students with the enthusiasm that only 
the spoken word can arouse. And to others they have always been most 
generous, even lavish, in giving ideas and momentum, partly out of sheer 
good-nature, but much more through the desire to watch the germination 
of the good seed that they sow broadcast and to see the harvest reaped, 
not by or for themselves, but for the advantage of the • science whose 
welfare is their chief care. 

During the early growth of the science, as in human families, it was 
the influence of the other parent that was most felt. From the earliest 
thinkers of Greece and Rome we have record of numberless observations 
and discoveries, sometimes in respect of minerals or organic fossils, some- 
times of unusual phenomena in mountains or volcanoes or in the relations 
of sea and land, generally leading to reasoned conclusions, many of them 
perhaps fanciful, some even absurd, but others so sound and far-seeing 
that they have not been upset at the present day. Many other countries, 
joining the favoured ones along the Mediterranean, carried the torch 
forward, and, in spite of the clogging influence of the vested intellectual 
interests of the day, the stock of knowledge gradually grew, until we find 
that Leonardo da Vinci was able to make as great an advance in the know- 
ledge of the earth as he did in his own arts of painting, sculpture, and 

It is true that during this period observers had a tendency to confine 
themselves too exclusively to one or other side of their subject, and were 
in the habit of reproaching one another with neglect of neighbouring 
branches, but even this made for progress by stimulating competition and 

In spite, however, of all that had gone before, in the fields both of fact- 
collecting and of speculation, it will be admitted that no single man made 
so great an individual advance, or placed it upon such an enduring founda- 
tion, or did so much on which the future of his science was to depend, as 
WiUiam Smith. And it is noteworthy that the spur to his discoveries was 
not so much his theoretical views or even his scientific zeal, as a plain and 
practical issue — the finding of a short-cut to speedy and accurate land 

The discovery by the ' Father of English Geology ' that fossils are the 
' medals of creation ' and that strata are each characterised by special suites 
of organisms was certainly one of the greatest ever made in the history 
of geology, and upon it have been founded directly or indirectly almost all 
the later advances in the science. But for the fuller utilisation of his 
discoveries there were needed the artistic faculty and a wide knowledge 
of places and people, both of which he fortunately possessed. Thus he was 
able to introduce handy, crisp, easily remembered and pleasantly sounding 
local terms to characterise his ' Formations,' and to represent the outcrop 
of strata on maps which were not merely topographical but, for the first 
time, were tectonic also. So well did he discharge this latter function 
that a comparison of his general map of England with the latest production 


of the Geological Survey on a scale at all comparable with it fills one with 
astonishment at the amount of work accomplished by him, single-handed, 
and with admiration for his accuracy. 

It is strange that, in the amateur and official work which followed 
during much of the nineteenth century, so little interest was taken in the 
industrial application of geological knowledge which in Smith's hands had 
been so productive. The science had, as has been said, the ' landed 
manner,' and the dignity of its appUcation to arts and industries was little 
appreciated. A former Director of the Geological Survey of Great Britain, 
Sir Andrew Ramsay, quoted with approval the saying of one of his 
colleagues, ' it is but the overflowings of science that enter into and 
animate industry.' And thus, though the scientific side of geology stood 
to gain much otherwise unattainable information from contact with its 
economic application, this source of knowledge was not fully utilised, 
and an air of mutual suspicion— not wholly unjustified — grew up between 
' theoretical ' geologists and those who applied geology to mining and 
other economic problems. Fortunately this feeling is passing away ; the 
two sides have found that each is indispensable to the other, and geologists 
are everyTvhere co-operating with those whose work is connected with the 
discovery or exploitation of the mineral wealth of the earth-crust. 

Material Service. 

Coal. — The first branch of industry to which geology made itself 
indispensable was coal-mining. Geology has long been in close contact 
with its problems, in mapping the extent of coal-fields, collecting inform- 
ation as to the succession of measures and the existence and lie among 
them of wants, faults, and igneous rocks, tracing the extension and 
variation of coal-seams, and estimating the resources available ; and, as 
seams are worked at increasing depths, and in those parts of fields concealed 
under thick unconformable cover of more recent formations, the work of 
the geologist has become more essential and increasingly productive. 

It is interesting to observe the application of the ' academic ' sides of 
geology to these more recondite problems, in unravelling tectonic com- 
plexes, in the collection of facts which may eventually elucidate the 
precise conditions under which different varieties of coal have originated, 
in applying knowledge as to the limits of the original areas of coal deposit, 
in the interpretation of stratification in the light of the progressive travel 
of coal-forming conditions geographically across the coal-producing areas, 
and in the stratigraphical relationship and exact mode of formation of 
the covering rock-systems. 

It is true that the accessibility of coals when first exploited, and their 
distribution in seams of varying quality, led, and in the newer areas are still 
leading, to much waste : waste on fruitless search in the fight of obtainable 
knowledge, in exploitation of good, thick, and easily worked seams to the 
neglect of poorer ones, in the non-preservation of satisfactory plans and 
the consequent leaving of derelict areas, in unsatisfactory drainage, and in 
the loss of valuable by-products. But there is a corresponding advantage 
to those of our generation that some exposed areas of complicated structure 
and many of the concealed coal-fields were left for ourselves and future 
generations by reason of working difficulties which it would have been 
premature to face in the time of easily obtained abundance. 


Even to-day, in spite of improved technical knowledge, there remain 
many areas in which information and inference are both scanty, and where 
difl&culties met in working have not yet been surmounted, while there will 
be in the future ample scope for improved methods and inventions to deal 
with coal at greater depths than those at which it can at present be 
economically worked. There is room for much new and more precise 
study than has yet been devoted to the variation of coal-seams, both in 
the vertical direction and when traced over the wide areas of their extent. 
Elaborate and knowledgeable samphng, followed by new means of testing, 
and these again by new methods for recognition of varieties, have still to 
be put into practice before it can be said that we are making a justifiable 
and economic use of the capital reserves stored up in the rocks. 

Oil. — While we blame our forefathers for their destructive and wasteful 
handling of the coal-fields, it is ourselves and our own generation that we 
must blame for serious waste of oil and the destructive exploitation of oil- 
fields that have been permitted. There is no economic subject to which 
geology has so direct a relation as the occurrence and exploration of oil- 
fields, and nothing in recent times has given so much employment and 
such valuable experience to geologists all over the world. It is the only 
example we have of the sudden introduction of a new source of fuel on a 
large scale in a late stage of industrial development, and it has already 
revolutionised many branches of engineering practice. The introduction 
and spread of the internal-combustion engine and all that this implies in 
space-economy, cleanhness, labour-saving, and comfort, has been the 
greatest engineering feature of the late nineteenth and early twentieth 
centuries, and it has given rise to systems and methods which mankind 
would be loth to abandon. The whole world is being searched to prolong 
the good times that we live in ; but in spite of the fact that there probably 
still remains a recoverable percentage in the oil-producing areas, and that 
there must be new fields awaiting discovery, there are already signs that 
the high oil-mark has been reached if not passed. But, again, it is no 
small comfort that although our supply of native oil, easily won and 
easily refined and applied, cannot last very much longer, there are 
abundant supplies of oil-shale still left, sufficient to take its place for very 
many decades to come. 

Metals, &c. — Although the greater part of to-day's session is to be taken 
up by papers and discussions on special sides of economic geology, by those 
who are tar more competent than I to speak on them, I cannot resist the 
temptation to say a few words on that side of the subject which touches on 
metal-mining. There is probably no subj ect which has been in the past more 
dominated by the ' practical man,' who may be defined as the most 
theoretical of all men, but whose theories are seldom proved and are often 
not susceptible of proof. The valuable information that was accessible to 
him has been wasted because he could not use it to the best advantage, or else 
it has been lost because he could or would not impart it. On the other 
hand, the ' theorist,' as he has been contemptuously named, has been 
hampered because he has often only been called in when difiiculties were 
excessive and when the train of facts or reasoning which would have been 
so valuable to him has been lost. 

In Britain the mining industry is so old and the mineral wealth in 
certain spots was so plenteous and accessible that the metal-mining 
geologist has had little chance. The eyes have been picked out Of ^j^g 


mines long ago, and in certain cases their very bones picked clean, and the 
country has been left in such a condition that its original state can only 
be guessed at, and problems of relationship, structure, and origin are 
past solution. Consequently it is in the countries which have not been 
inhabited bv successive races of highly civilised peoples, or in relation to 
substances for which there was in the past little or no demand, that the 
subject has been susceptible of real advance. 

Thus it is that such strides in mining geology have been made in 
Canada, the United States, India, South Africa, and Australia, where 
there has been a fair field to work upon, and where preliminary surveys 
have opened up the country and given an idea of its hidden resources. In 
no other areas of the world has the work of official surveys been watched 
more carefully by men of capital and enterprise, and money has rarely 
been lacking for development where there seem to be prospects of a fair 
return for it. Fortunately, too, the training of official geological surveyors 
has provided a type of geologist exceptionally well fitted both to prospect 
independently and to follow out in minute detail, and from a different 
view-point, the preliminary and less detailed examination which is all 
that is practicable in an official survey. These men have- carried with 
them not merely competence and enthusiasm, but a thorough belief in 
scientific principles, an extensive knowledge of border-line sciences, and 
the ability to apply both principles and methods to the problems involved. 
In the hands of such men the surest guides are scientific principles, just 
as in the hands of those with ' a little learning ' imperfectly understood 
principles are most dangerous ; and as the search for ores becomes keener, 
and as deposits smaller and more tenuous become worth working, the 
need for increased knowledge of principle and for minute detail in observa- 
tion steadily grows. 

Fortunately, we have not yet exhausted the existing stores of highly 
concentrated and singularly pure ores, salines, refractories, &c., and the 
need is less acute than it will eventually become for miich-improved 
methods of concentration and purification. When we feel the pinch it 
will be necessary to call upon the chemist to endeavour to make available 
the abundant supplies of less pure and less concentrated materials which 
will remain over for our successors when we have picked out the best. 
This has already been to some extent effected for oil and it is beginning 
for coal ; it must eventually be done for the still less pure sources of these 
two substances, for less concentrated ores and the like. 

Stone, &c. — The geologist has already done much in the investigation 
of the qualities of building- stones, plastic substances, and the materials 
for roofing and cement. To a large extent the materials in use are 
satisfactory in the air and surroundings in which they occur in Nature. 
But the added problems of a town atmosphere, accompanied by increased 
stresses in large buildings and the modern demands of the architect and 
sculptor, have still to be met, if our buildings are to be more permanent 
and our towns to present a less weather-beaten aspect than they now do. 
New and reliable means of testing are required, and we need a more 
thorough'understanding of the reactions produced by impure atmospheres, 
and the effects of the'presence or absence of protective or destructive 
organisms. Future investigation will react in the production of more 
satisfactory preservatives, and it may lead to increased production and 


adoption of artificial stones devoid of the qualities which undermine the 
power of resistance of natural stones ; at the same time more control over 
colour and shaping may be obtained. 

Roads. — Closely akin to the subject of building materials comes that 
of stones used for flagging, paving, and metalling of roads, to the provision 
and study of which the geologist has already very largely contributed. 
New problems are daily introduced as road traffic becomes heavier and 
as roads are required to be freer from dust and vibration. Already many 
waste products have come into valuable utilisation, and a wide range of 
road metals which can be called upon for these purposes exists in almost 
every country. 

In the siting of roads, railways, and canals, however, geology could 
render much more useful service than it has yet been called upon to give. 
The routes that are cheapest to make are by no means the cheapest to 
maintain, and the geological survey of routes would very often suggest 
slight deviations which would be more economical in the end than when 
the shortest route compatible with the gradients is taken. 

The princes of road-makers in the old world, the Romans, were perhaps 
too heroic in their dealing with gradients, but they exercised quite remark- 
able skill in choosing such directions as to secure the least formidable 
slopes consistent with the general design of their routes. Their roads 
were, however, constructed primarily for strategic purposes and secondarily 
for transport, and it was necessary to sacrifice something. On the other 
hand, the constructors of the coach-roads were, perhaps, too sensitive to 
the psychology of their horses and the limitations of their vehicles, and 
their roads are not ideal for present-day traffic. Some compromise seems 
to be required between the two methods, and not the method of the 
Roman tempered by the cuttings and tunnels of the railway engineer. Now 
that we have a vehicle that rejoices in a hill, whether for or against 
it, and for the first time have a means for hill-climbing at speed, it is a pity 
to flatten down gradients too much ; and though it is legitimate and even 
necessary to remove dangerous crossings and curves, itshould be remembered 
that an everlasting straight vista is as exasperating to a driver as it is 
heart-breaking to a horse. And if roads of this most desirable type are 
to be satisfactorily and cheaply maintained, it will be more than ever 
necessary to study routes in relation to the rocks that are traversed and 
the water contained in them. 

Something of what has been said with reference to roads appHes with 
equal force to other engineering undertakings, railways and canals, 
harbour-works, bridges, and large and heavy buildings, particularly those 
intended to stand for centuries. The general success of such works is 
ample testimony to the knowledge and skill expended upon them by 
engineers and architects, as well as to the elastic toleration of sites so 
heavily taxed ; and one is tempted to believe that a much larger amount 
of study has been given to geological questions in these cases than is 
usually admitted. 

Water. — Of all engineering questions, that most closely involved with 
geological science is probably water-supply. So far as underground 
water is concerned, geologists and engineers working together have 
amassed a volume of fact and principle which has not yet been completely 
codified and rendered accessible. An unexpectedly large proportion of 


the available rainfall has in many instances been obtained by successful 
drilling, in spite of the complication of the question by surface pollution, 
and in the face of many legal inanities and much charlatanry. And 
the extension of these methods to arid regions, as in Australia and 
North Africa, has brought under cultivation large areas which needed 
nothing but the ' striking of the rock by the rod ' of the driller to make 
new oases in the desert, and thus render available some of the richest soils 
in the world. 

Much the same is true of overground supplies, which have been a bless- 
ing not merely in the towns and lands supplied, but to the rivers and 
drainage basins regularised and protected in large measure from ever- 
recurrent floods and the damage consequent upon them. Although in 
such works geological conditions are often taken into full account, an 
elaborate geological survey at a very early stage would in most cases more 
than pay its way. Such a survey would not only give a good preliminary 
idea of the nature and tectonics of the rocks underlying sites of dams 
and reservoirs, but it would save its cost in limiting the number and in 
giving rational direction to the inevitable pits which must be sunk, by 
restricting them to the elucidation of points which the surface mapping 
leaves obscure. It would at the same time direct attention to the 
innumerable pitfalls which sites often present and would generally provide 
on the spot much of the requisite material for construction. 

It is an arguable question whether the expenditure of such vast sums 
as have been devoted to the supply of large towns is entirely justified. 
The provision of a single supply of which large quantities are used for 
drinking, cooking, and industrial purposes, necessitates that the water 
shall be of immaculate purity, and this pure substance, the purest of all 
the things we consume, is employed — may we not say wasted ? — for 
flushing, washing, and a host of other purposes for which a less pure water 
would suffice. Surely the time has come when people could be educated 
up to the use of a dual supply, and this should be a commercial possibility 
where the area served and quantity used are really large. The experience 
of London has shown the very high cost of a single supply to all consumers 
and for all purposes, and the limits of future supply are almost in sight. 
It seems to be time that the problems of a dual service should engage 
serious attention. 

Power. — Owing to the configuration and rainfall of the British Isles, 
and their congested population, we are apt to think of water questions in 
terms of supply, and, though we are using a certain amount of water for 
power, there is only a limited development possible. In many other parts 
of the Empire, however, this is becoming a valuable asset, and nowhere 
more than in Canada, whiteh is rapidly developing its resources on a very 
large scale. What has been said with reference to water-supply is of 
equal application here, for the physiographic conditions which bring about 
steep gradients, accompanied by large bodies of water, introduce factors 
of denudation, transport, and deposition by the water which call for most 
careful selection of sites for reservoirs and works, if the all too frequent 
disasters are to be avoided, and if the schemes are not to be ephemeral in 
duration and excessively costly in upkeep. 

With sources of power other than coal and water — including that 
of the tides — the geologist has little concern. But there has been brought 


into service, at Volterra in Italy, a new source of power in the high- 
temperature steam from fumaroles which had previously been used only 
as a source of borax. Now the steam is being tapped by borings adven- 
turously carried out, and its chief heat is employed in running great power 
stations, only the residual heat being given up to the manufacture of borax. 
This may be but the beginning of the application of a new and valuable 
source of power in which the services of geology will be required and from 
which that science stands to'learn much. We are haunted by the fear 
that a limit will be imposed by high temperature to deep mining, while 
that very heat may provide energy as valuable as the material which 
would otherwise be mined ; 'just as we dread the gas from certain coal 
seams when the gas might, if it could be exploited, give a return equivalent 
to that of the coal itself. 

Agriculture and Forestry. — Leaving aside relations already touched 
upon, the connexion of geology with agriculture and forestry is through 
the medium of soils and subsoils, and, though the geologist seems unsuited 
to deal unaided with soils, his methods are those which the soil investigator 
must use ; and soil surveys are now being carried out by agriculturists 
working in conjunction with geologists. This results in giving new and 
valuable facts and inferences for the benefit of both sciences. On the 
geological side it is rendering more available the facts of plant distribution, 
and what has been called agronomics, which, speaking for myself, 1 have 
always found very hard to get hold of. On the other hand, the services of 
geologists are likely to be of especial value in the matter of transported 
soils, loams, loess, brick-earths, drifts, gravels, and the like, where the 
conditions of formation may in many cases provide a key to their 
peculiarities. The same considerations apply to forestry, and here in 
addition well-established facts, such as the successive forest types dis- 
played in peat-bogs, may betray principles that will be of service in 
practice. Questions of site, sewage disposal, and health are bound up 
with questions of water and agriculture and need no further notice here. 
Military Science. — It will be readily admitted that geology has been of 
conspicuous service in connexion with military operations in such ways as 
the siting of camps, trenches, and dug-outs ; while the minute study of 
the water-table in northern France during the late war was not only of 
value in obtaining water supplies but was of conspicuous utility in mining 
and counter-mining, in which exact and detailed knowledge was success- 
fully pitted against a knowledge which was ' just there or thereabouts.' 

The ' eye for a country,' the visualising; of features plotted on maps 
and making the utmost use of them, qualities on which good strategy is 
founded, are the same qualities which are essential to a competent geological 
surveyor ; and I cannot help thinking that strategic ability would reap 
as much advantage from a knowledge of the underlying canons of topo- 
graphic relief as the geologist would from a study of the principles of 
military topography. It was a wise scheme to train the British Home and 
Overseas armies on ground similar in kind and in relief to that ou which 
they were about to fight in France ; but it should have been realised that 
physical causes and the resultant topographical relief differ in essential 
particulars in temperate and tropical climates. 


Innumerable as are the services which the science of geology has ren- 
dered to man on the material side, these are at least equalled, if not out- 
weighed, by those rendered on the intellectual side, either in the direct 
application of its principles to the life of mankind, or in the aid given to 
other sciences and the confidence engendered in such of their conclusions 
as can be tested in the light of geological history. 

Throughout most of its range and in its more special directions, geology, 
like zoology and botany, is mainly an observational science. Multitudes 
of facts have to be observed and grouped, and as much skill is required in 
selecting from them the more significant and decisive as in collecting them. 
Experiment for the most part is of service in the criticism and verification 
of tentative theories ; and, on the physical and applied sides more espe- 
cially, it is becoming of great value. But the process of examination-in- 
chief, and the cross-examination in the field by a highly qualified and fully 
trained observer, are so exhaustive that not very much is left to submit 
for checking to the experimenter. 

Even more than either of these two sciences is geology an open-air 
science, and one which calls for and imparts a love of Nature, that cannot 
but deepen as knowledge increases. Its most interesting work lies as a 
rule in the districts most attractive for other reasons. In the course of 
geological work the country must be thoroughly traversed, and, when 
possible, should be seen again and again, in all lights, under all aspects, 
and at all times and seasons. Hypotheses grow but slowly, and call for 
constant checking or verification in the field, the gradually growing ideas 
being an intensive spur in the collection of new facts or the re-observation 
of old ones, and in the comparison with like or unlike cases published or 
unpublished. But, as they grow, hypotheses give to their framer a 
power of prediction, more precise as the hypothesis is better founded ; and 
one of the most fascinating parts of his work is the testing out of such 
predictions and the making of crucial observations thus needed and 
inspired. It is for these reasons principally that geology has earned its 
reputation as a fighting science. It is hard to decide just exactly when 
evidence amounts to absolute proof ; and difterent observers, having 
reached varying stages in the completeness of their observations, may be 
led by the sum of them to different explanatory theories ; or in the sphere 
of their own work they may be specially influenced by facts current 

This seems to be the place to enter a protest against dominant 
ideas with regard to education and training in geology. The tendency in 
early education has been to squeeze out other sciences in favour of those 
that are called fundamental, and to suppose that, because it makes use 
of most other sciences, training in geology ought not to be begun until all 
others have been mastered. This is to go counter to the history of the 
science itself. Its leading methods were evolved in the early days of 
physics and chemistry and by men often ignorant even of such principles 
as were then understood. As geology has grown it has given to these 
sciences many problems for solution in return for the solutions received, 
problems which would have long waited for attention had not their 
geological application been urgent. Further, as the solution of his 
problems requires not only a very extensive knowledge but a workmanlike 
ability to apply both methods and principles, it is difficult to say at what 
1924 H 


stage even the most competent scientific man, if he is ultimately to deal 
with all his problems himself, can be ready to begin the study of geology. 

Meantime, qualities of far higher value to a geologist, which in most 
cases can only be acquired young, are being lost, such as the habit of close 
observation, the aptitude to distinguish minute resemblances and difier- 
ences, and the faculty of judging tendencies, together with the instinct 
and patience to make collections. These propensities come very early 
and speedily become blunted if not exercised. I would advocate, with all 
the earnestness of an old teacher, that some form of earth-knowledge 
involving observation of facts and collection of specimens, and the 
drawing of inferences from them, should find a place in schools and be 
encouraged at the Universities side by side with the fundamental sciences. 
Such studies will not possess the meticulous exactitude of the others, but 
in this respect their tendency may be corrected by them. They will, however, 
bring the student into contact with realities, things as they are, instead of 
inaccessible, abstract conceptions, things beyond experience — such as pure 
substances, or forces acting in the absence oi friction. They will give him the 
thrill of discovery and explanation, teach him that the end of science is to 
extract law and principle from observation and experiment, and, instead 
of keeping him along rigid lines to an assured and pre-obtained solution, 
will give him a choice of approach and accustom him to frame and test 
hypotheses which to him at any rate will be new and his own. Further, 
they will do much to teach him his own shortcomings and give him a keen 
incentive to acquire the very sciences which in themselves may be dull or 
even repulsive until he has convinced himself of their utility and necessity 
to his own work. 

While acknowledging indebtedness to those sciences which have so 
generously contributed their results to geology, we feel that we have some 
ground for complaint that at times their votaries have not resisted the 
temptation to drop bombs which have exploded in our midst and produced 
a certain amount of trepidation and sometimes legitimate indignation. 
We consider that it is up to those who feel compelled to do this to acquire 
some knowledge of geological principles and of the lines of reasoning on 
which they are founded. They should recognise that a pyramid is diffi- 
cult to upset, because in the process of building it the materials and 
structure have been carefully selected and tested by the builders. To be 
told after a century's search and reasoning that we must take our time 
bill and ' sit down quickly and write ' off SO or it may be 90 per cent, of 
it, ought not to have disturbed us as much as it did, not more indeed 
than now does the permission of the representatives of the same science to 
multiply our original time bill, if we like, by ten or twenty, or even more, 
so far as their present state of knowledge extends. Our answer is that 
we have not done the one and have no desire to do the other, so far as the 
sedimentary rocks at present known to us are concerned. 

The geologist, however, should be, and is, the last to deprecate the 
application of the highest and newest conclusions of physical and chemical 
science to his own problems and to the criticism of his solutions of them, 
for it is certain that this will always result in doing much to reduce many 
of the barriers which retard his advance. For this reason we must wel- 
come even so fantastic a hypothesis as that of Wegener, for the problem 
of the overthrust ' nappes ' of mountain regions is one of our greatest 


difficulties, and all explanations hitherto proposed are so hopelessly in- 
adequate that we have sometimes felt compelled to doubt whether the 
facts really are as stated. But the phenomena have now been observed 
so carefully and in so many difierent districts that any real doubt as 
to the facts is out of the question, and we must still look for some 
adequate method by which the overthrusting could have been brought 
about. And if dozens of square miles of ground have been shifted over 
their foundations and away from their roots for many linear miles in the 
course of a single geological Period, who shall say what might not be 
accomplished in the course of Eras ? 

Important consequences flow from the fact that the goal and expression 
of most geological research is the construction of a map of the area studied. 
To the layman who studies a country with a geological map in hand, 
it is hard to resist the conclusion that the map is merely fanciful ; he 
can see no evidence for the lines laid down or the symbols employed, 
and he is astonished when trenching or drilling proves their correctness at 
any particular point. It is difficult for him to see or to realise the cumulative 
force of the aggregation of minute pieces of e^ddence, slight differences in 
slojje or soil, variations in quality, quantity, or luxuriance of vegetation, 
variations in dryness or moisture, the distribution of culture, the extension 
into the area of some underlying tectonic plan — the laws of which may 
have been worked out elsewhere — and the thousand-and-one considerations 
which go to make up the mind of the geologist. 

It is, of course, perfectly true that the individuality of the surveyor 
enters not a little into the extrapolation of geological lines beyond the 
points where direct observation of the rocks is possible. So much is this 
the case, that it is feasible, from the inspection of his map, to gauge, not 
only the geological competence, experience, and attainments of the 
surveyor, but his knowledge and grasp of physiograjjhic form, liis power 
to see into intricate solid geometry, his artistic skill of hand and eye, and, 
above all, that indefinable quality, his ' eye for a country,' on which so very 
much depends. 

The construction of a map has the further advantage that it grows by 
the alternation of periods of observation in the field with periods devoted 
to the thinking out of structure after each day's work and in the intervals 
between successive visits to the field, so that, with every return to the 
ground, the facts may be re-observed and lines re-tested in the light of 
growing knowledge. It is true that ideal observation should be so complete 
and exact that re-observation has nothing to teach ; but, as a matter of 
fact, with a map as with a book, what one takes from it is what one brings 
to it, clarified, improved, and extended. There should be allowed to pro- 
fessional geological surveyors as much elasticity as possible, so that, in 
addition to detailed and exhaustive primary survey, there may be frequent 
revision in the light of their own work and that of their neighbours. In 
this respect the hand-coloured form in which geological maps were originally 
pubHshed has an advantage over the newer, cheaper, and more consistent 
colour-printed maps. 

Geologists should give a cordial welcome to the new aid provided by 
aerial survey and photography. This provides the last point of view of 
their areas which has been hitherto denied, though they have been in 
the habit of making use of the only substitute open to them, prospecting 



and photographing from the highest points accessible. Many unexpected 
results have thus been secured in archaeology, and at least as much may 
be looked for in geological surveys even in settled and surveyed districts, 
while in unsurveyed and unprospected regions its use is proving of the highest 
importance. Too much credit cannot be given to Canada for its enter- 
prise in using this method for the prospecting and preliminary survey of 
the animal, vegetable, and mineral resources of its great hinterland by 
means of the aeroplane. A great saving in time and cost has thus been 
secured, and the method bids fair to remove the reproach levelled at the 
British Empire that such vast areas of it are practically unknown. 

Physiography and Geography. — It is because of the variety and intensity 
of observation essential to geological surveying — in the course of which 
every acre of his ground must be traversed, and much of it re-traversed — 
that the geologist must necessarily become a physiographer and 
geographer. There is a limit to the perfection of topographic maps 
and surveys, even when, as in the United States, there is close co- 
operation between the Topographic and the Geological Surveys ; and 
it is the duty of the geologist to take note of innumerable features which 
have no delineation, still less explanation, on such maps. The geologist 
is probably the only class of person who has to traverse large areas with his 
eyes open not to one class of phenomena only, but to all that can help him 
to decide questions of concealed structure ; and he naturally seeks to 
supplement this by personal contact with the inhabitants, and with their 
written and unwritten records, which it is part of his business to interpret 
and explain. Nor can be confine himself to the purely physiographic 
aspect of his area. He is led into bypaths as a by-play, and many facts 
with regard to the distribution of animals and plants, and of the dwellings, 
occupations, and characteristics of the people, can scarcely escape his 
observation ; neither can he shut his eyes to historic and prehistoric 
facts. Thus, when a geologist leaves his district, he is generally possessed 
of a store of knowledge reaching far beyond the strict bounds of his 

"While geologists, from the conditions under which they work, have 
been able personally to make individual contributions to these sciences, 
the most important service of geology as a whole has been the trans- 
formation of geography from a static into a dynamic science. In its 
earlier stages, geology discovered that progress involved the close study 
of the earth of the present and the application of that knowledge to 
explain its past changes ; and the progress of geology has only 
intensified both the need of deeper study and the fuller application of 
it. To-day it is essential for geographers to be perfectly familiar with 
the past history of the earth in order that they may be able to explain 
the phenomena of the present. 

The question may be summed up by saying that geology has become a 
physiological study of the earth as an organism with a life all its own. 
We can watch the geographical changes through which the earth has passed, 
revealed as they are in the nature and distribution of rocks and fossils. 
We can even discover the dry land — the actual landscape and physio- 
graphic relief itself — preserved in a fossil state, and judge from it the 
climates then prevailing and their distribution in distant epochs. We can 
form some idea of the modes of origin and dates of appearance of continents 

C— GEOLOGY. 101 

and mountain chains, and other leading features of the relief of the crust. 
We are learning to read the evidence given by the interactions of igneous 
and aqueous rocks as to the nature of the stresses by which the structure of 
the crust itself has been moulded. There are, it is true, many gaps in our 
knowledge, but their very existence is of value in quickening and directing 
research in order that our history may become as full as it can possibly be 
made. Each advance upon the technical side of the subject, the pursuit 
of detailed zonal stratigraphy, the application of the microscope in so 
many new directions, and the broadening of the area of study, all react 
sooner or later in improving, refining, and extending our knowledge of 
earth history. They combine with the evidence of palaeontology to con- 
vince us that this earth of ours is still young, active, and full of life, and 
that any process of ' running down ' is constantly being held by self-acting 
checks which are putting forward to vastly distant ages ' all prospect of 
an end.' 

Biological Sciences. — While astronomy has given us the conception of 
illimitable space, it has done much to destroy what has been called the 
anthropomorphic view of creation. Geology, on the other hand, has en- 
dowed us with an almost limitless conception of time, but has done some- 
thing to rehabilitate the importance of man as the highest product yet 
reached in the long history of the earth. 

This it has done, in the main, through the intense reality that it has 
given to the conception of evolution. Although several authors, and two 
in particular, have pointed out that such a conception could not have been 
formed without the postulates of time and continuity of existence contri- 
buted by geology, it is hardly realised how much geological labour on the 
life of the earth, and on life on the earth, as summed up by Lyell and 
grouped and presented by him in his great work on ' The Principles of 
Geology,' was necessary to give to evolution a concrete and cogent appli- 
cation. The function of this labour could hardly be better indicated than 
by the position of geology as displayed in Lyell's earlier editions. The 
modern reader of them is continually haunted by the feeling that the 
author was struggling for a single missing generalisation which he failed 
to find ; and although, in almost every branch of the subject treated, 
Lyell leads up again and again to the missing conception, and though the 
facts and inferences which he marshalled can now be seen to be marching 
on this great idea, he never quite succeeded in attaining it for him-self. 
It was left for Darwin, than whom no one was more conscious of what he 
owed to Lyell, to see that the facts must rest on some great single funda- 
mental principle, to realise that this principle was evolution, and to apply 
it to his own branch, the development of life. 

Lyell had proved that the long history of the earth as recorded in the 
rocks revealed the operation of causes, small in relation to the earth as a 
whole, but persistent, the majority of them still in action. It was a further 
debt to Lyell that Darwin shoiild bring in the continuous operation of small 
causes as the machinery operating and guiding the evolution of life. 

But though the work of geologists, as summed up in Lyell, provided the 
starting-point for the conception of organic evolution, it did not stop here. 
The idea of Uniformitarianism in which that work culminated was meant 
as a reaction against the fantastic operations postulated by the Catastro- 
phists, and was never intended to imply that these causes in the past 


were always balanced or distributed as they now are. There was in 
Lyell's statements nothing to indicate that denudation or earth-movement 
might not have been more active at periods of the past, that organic change 
might not accelerate or slow down, that there might not be variations in the 
trends of continental or oceanic development resulting in climatal and 
other changes, or that the very sources and intensities of energy from out- 
side or inside the earth might not seriously vary. Only, warrant must be 
found for all such suppositions with regard to the earth of the past from 
fuller study of the earth of the present. And if we recognise the inner 
spirit which inspired the eloquent words of Lyell, when he had grasped 
that Darwin had supplied the one missing idea, we cannot fail to see that his 
Uniformitarianism included evolution as one of the ' existing causes ' to 
be taken into consideration. 

The physiology of the earth, however, is that of a very complex 
organism, and we are sure that we do not yet know all the forces internal 
and external acting upon it, still less their relative value and intensity, their 
distribution and variation in the past, or the precise records which each is 
capable of imprinting on the rocks of the earth-crust. But it is becoming 
clearer that there has been a periodicity in the stages of development of the 
earth-crust, and that on these great pulses of earth life there have been im- 
posed innumerable waves of smaller cycles ; and that, on account of their 
interference with, or reinforcement of, one another, the simpler type of 
cyclic repetition which might have been looked for in the history is masked 
and broken and diversified by actual happenings of an infinite variety. 
Van Hise more than once complained of the tendency of geologists to adhere 
to single explanations of events, and advocated the necessity of considering 
the co-operation of many causes ; and it may well be that in many out- 
standing problems, such as past glacial or tropical periods, coral reefs, 
stages of earth movement, progression and regression of the oceans, we may 
find the ultimate explanation in the interaction of a number of ' true causes." 


During the long period of time comprised in the history from the Cam- 
brian Period onwards, the slow and persistent evolution of plant and 
animal life went forward and left ample record in the rocks. To warrant a 
belief in organic evolution, we are no longer solely dependent on reasoning 
founded on existing organisms or on the facts of their ontogeny and 
distribution. As M. MarceUin Boule says in his work on Fossil Man, 
' . . . . pour tout ce qui a trait a revolution des etres organises en general, 
le dernier mot doit rester a la Paleontologie quand cette science est en 
mesure de parler clairement. Les plus fins travaux anatomiques, les 
comparaisons les plus approfondies, les raisonnements les plus ingenieux 
sur la morphologic des etres actuels ne sauraient avoir la valeur demon- 
strative des documents tires de la roche ou ils sont enfouis et disposes 
dans leur ordre chronologique meme.' * Although we are only too pain- 
fully aware of the innumerable chances that conspire to prevent an animal 
or plant from securing immortality by preservation as a fossil, the finding 
of better-preserved material, the more skilful preparation of it for examina- 
tion, and the application to it of refined biological methods, such as 
careful dissection and the serial sections of Professor Sollas, are giving 

* MarceUin Boule, Lts Hommes Fossiles, 1923, p. 453. 

C— GEOLOGY. 103 

us more complete and accurate knowledge than ever before. It may now 
be confidently stated that many of the most crucial links in the chain 
of evolving life are in our hands, that they actually lived in the past, 
and that their fossil forms show their relationship to their predecessors and 
successors. The time has come when Darwin's famous chapter on the 
' Imperfection of the Geological Record,' an apology written with the most 
balanced criticism and unbiassed judgment, should be rewritten and 

It is true that we seem as far as ever from unveiling the points of 
divergence of the great phyla, and we can but feel that the time from the 
beginning of the Cambrian Period onward is but a small part of the whole 
history of life on the earth. As with antiquarian research, each new 
discovery in geology, whether on the physical or the biological side, only 
brings these distant ages more fully into view and emphasises their 
modernity and their likeness to our own time. Button's famous dictum 
that he saw ' no vestige of a beginning, no prospect of an end,' is to-day 
more true than ever, when we regard the evidence of stratified rocks. 
But we know enough to convince us that within post-Cambrian time 
evolution has steadily proceeded from general to special, from simple to 
complex, from lower to higher efficiency. 

In almost every subdivision of the animal kingdom, and in not a few 
branches of the vegetable kingdom, lines of descent and directions of 
specialisation have been made out, sometimes visibly operating through- 
out whole Systems, but more usually through smaller divisions of the 
record ; and this in the former kingdom not only among vertebrates but 
among the invertebrates and even their lower sub-kingdoms. It may 
even be stated that in methods of defence, in food-procuring in the attain- 
ment of favourable positions and attitudes, something very closely 
imitating what would be expected on the doctrine of the origin of species 
by ' survival of the fittest ' has again and again occurred. 

The essence of evolution is unbroken sequence, and when we consider 
theextraordinary delicacy of the adjustment of life to its physical and organic 
environment, the mutual interdependence of fife forms, and the necessity to 
them of such factors as favourable range of temperature, food, climatic 
conditions, soil, and the continuity of the ' element ' in or on which they 
live, it is most wonderful that in the vast lapse of post-Archsean time it has 
been possible for life to exist continuously, and continually to evolve, 
throughout those long ages. And this in spite of the fact that, although 
the main chain has been unbroken, conditions have, in many cases, been so 
unfavourable that whole groups have flourished and died out, while others 
have become so attenuated that only a few survivors have been left, highly 
restricted in distribution, to burgeon out again when the unfavourable 
conditions were removed, or in other places where conditions have again 
become more favourable to them. 

That life has survived continuously in spite of the vicissitudes through 
which it has been compelled to pass, and the frequent convergence upon it 
of unfavourable conditions, may well be taken to heart by those who fear 
that civilisation will be brought to an end by the misuse of the powers that 
itself has evolved. They may surely take courage and trust that the 
remedy for these evils will come, as it has in innumerable other cases, 
not from conventions and understandings that, as all history shows, will 


be mere scraps of paper, but from the intonsive application to them C'f 
the very science which has evolved them. 

Although the geological record is and possibly will always remain 
incomplete, it has yet proved remarkably representative, and certain out- 
standing facts have been made out which are sufficient to show that the 
lines of organic evolution as recorded in geology are in accordance with 
what is theoretically probable, and with those taken by the evolution of 
domesticated organisms and by human arts and inventions. 

1. There can be no doubt that the stages of organic evolution are 
correlated with and were actuated by the stages in the inorganic evolution 
of the earth itself. That climatic change was effective in inducing migra- 
tion, and thus in sharpening the struggle for existence against both enemy 
organisms and changed physical environment ; that extension and restric- 
tion of land and water areas in some cases brought about keener and more 
varied competition, change of habit or food, and in others the destruction 
of potential enemies and the securing of the advantages of a fair field for 
the survivors ; and that activity of the earth-crust in such things as 
deposition and mountain-building provided conditions for the existence of 
an increased range of varieties and the consequent struggle between them. 
If we are not allowed to say that this brought about the survival of the 
fit, it at least caused the destruction of the unfit. 

2. It may be stated as a biological law that every locality becomes 
' full ' of life, forms arriving or evolving to take advantage of the special 
facilities offered. In consequence, resistance to the incursion of new 
forms, even if they are exceptionally equipped, is very great, and it is 
only occasionally that such new forms can make good their immigration. 
There are, of course, marked exceptions, but these generally occur w^hen 
degeneration or overgrowth in size accompanied by neglect of means of 
defence have occurred, or when an area has been for so long sheltered from 
the wider and more general course of evolution that it has fallen seriously 
behindhand in the race. 

The geological record gives indirect evidence of the same ' filling ' of 
areas in the past in the extraordinary slowness with which advanced types, 
that have eventually made great headway, established themselves after 
their introduction ; the earliest fishes, reptiles, and mammals are cases 
in point. Imperfect as the first members of these groups undoubtedly 
were, they must, even shortly after their introduction, have possessed 
considerable advantages over the older and established forms with which 
they found themselves in competition. In size and strength they were 
doubtless inferior, and probably they must have taken long periods to 
make good their advantage. But in all such cases the new forms went for 
a long period into ' retreat,' and, in face of the apparent slowness of their 
evolution and the bitter competition to which they were subjected, it is 
remarkable that they overpassed the troubles of racial youth, and 
eventually took the place to which they were entitled in the scheme of 
life. It seems justifiable to believe that there must have been at least 
some well-equipped types which did not survive competition in these early 
stages, but went under with all their promise of future success. We can 
easily imagine that the survival of such, had it occurred, may have altered 
the whole course of evolution and produced a life story very different from 
that we know to-day, and of which we ourselves form no small part. 

r.— GEOLOGY. 1 05 

3. Not less remarkable than the period of ' retreat ' is that of booming 
development which at last came to each successful modification. In this 
connexion we can instance the ' pleine evolution ' of the graptolites, the 
euechinoids, ammonoids, and belemnoids, the fishes, reptiles, birds, and 
mammals, each in its own time. Each slowly but surely built up its supre- 
macy, and then wantoned through long ages as the lord of creation in its 
own element and in its own day. Both the period of sanctuary and the 
subsequent boom can be closely paralleled by the case of many human 
inventions and in the occupations and history of mankind. 

4. But while there are outstanding cases in which a line of advance 
is taken that is capable of successive improvements and leads on to con- 
tinuous success, there are many other instances in which the line of 
advance, though temporarily advantageous, has only been carried through 
a limited number of stages, and eventually failed either by its inherent 
inadequacy or by imposing so heavy a burden on the economy of the 
organism that it was unable to bear the cost. 

The only instance I need quote, though there are many others, is the 
use of defensive armour, spines, plates, hooks, horns, &c. _ These provide 
an obvious method of resistance to attack, and this defensive attitude has 
been practised by one group of organisms after another, but always with the 
same disastrous result, the imposition of a fatal strain on the organism to 
meet renewed, perfected, and more vigorous attack. The spinose grapto- 
lites and trilobites, the armoured fishes and reptiles, are cases in point, 
and in the last of these instances, at least, victory rested with the acquire- 
ment of swiftness in movement, accompanied by increasing power of 
attack such as is given by the development of teeth or claws or both. 
Again and again in the Tertiary Era one group of mammals after another, 
before, or more usually after, the attainment of great size, has taken to 
some means of sedentary defence, and in every case the cost of upkeep 
has been too great and the group has gone under. Every time the race 
has been to the swift, active, and strong, and those that trusted in 
' passive resistance,' in ' defence and not defiance,' have gone under in 
competition with those that have been prepared to face the risks involved 
in attack. The fact that turtles and armadilloes have survived to the 
present endorses rather than vitiates the principle. 

Other cases of rapid decline or sudden disappearance are more difficult 
to account for. The waning of the brachiopods but not yet their dis- 
appearance, the disappearance of the pteridosperms, the rugose corals, 
the belemnoids and ammonoids synchronising with the vanishing of many 
orders of reptiles, will long furnish subjects for research by biologists 
and geologists. And it may well be that the explanation will often lie 
along biological rather than physical lines, such as those suggested for 
the graptolites ; Lapworth pointed out that their disappearance— in spite 
of a brave el?ort of passive resistance — synchronised with the great develop- 
ment of fishes, and the assumption by them of many of the functions pre- 
viously discharged by the trilobites. In other cases the explanation may be 
more m the direction of that given for the reptiles to be referred to later. 

The rarity in the geological record of some of the stages in evolution, 
and the absence of others which must surely have existed, may receive 
some explanation from what has frequently occurred in the history 
of human invention. If variants arise and are subjected to intense 


competition, tliej^ have no chance in the struggle for existence unless they 
show rapid improvement and development of the favourable variations 
within a few generations. Hence the numbers exhibiting each of the early- 
stages of change will always be few and the chances of their preservation 
slight. Those who have tried to work out the stages in the history of an 
invention, for instance, will appreciate the rarity of ' missing links ' and 
the difficulty of filling in every step towards the later perfection. These 
are looked upon as ' freaks ' and, unless they present real and marked 
improvement, are never manufactured on a large scale. Their numbers 
consequently are few, and many of them are the victims of experiment 
and often do not survive the experience. 

5. Perhaps the most wonderful result disclosed by a study of the later 
part of the geological record is the steady and unbroken evolution of brain 
from the earliest vertebrate animals to the present. The exceeding 
slowness of the process in its early stages is not less wonderful than its 
acceleration during the latest stages of geological history. The disappear- 
ance of so many orders of reptiles at the end of the Mesozoic Period, at the 
close of a long and most promising chain of evolution, indicates that there 
was some inherent weakness underlying the line of evolution entered upon 
by them, which proceeded so far and favourably that it was impossible to 
retrace the path. This may well have been connected with the substance 
or construction of brain and nerve. If so, this side of evolution has to be 
seriously reckoned with, and it may be that the fundamental weakness of 
physical as opposed to intellectual evolution brought this flourishing and 
well-developed group to its end. 

It has, of course, been suggested by Searles V. Wood, jun. {Phil. Mag. 
xxiii, 1862), and others, that the destruction of Mesozoic life types was 
brought about by physical changes ; but, apart from the fact that the 
particular changes supposed by the former did not as a matter of fact 
occur, the entire explanation provides a cause utterly insufficient in com- 
parison with the potency of organic struggle against creatures better 
endowed with warm blood, adequate brain substance, and the activity 
and enterprise springing therefrom. 

In spite of the evidence of acceleration as the higher ranks of animals 
are reached, and in spite of the extraordinary efiiciency of the human 
brain and all the benefits to the organism it brings about, we may well 
be appalled by the geons which have been used up and the millions of varie- 
ties which have passed away in the production of this, the most efficient 
scientific apparatus yet invented or evolved. 

6. But if it has taken long ages to evolve an animal capable of a 
broader geographical distribution than any other, with a constitution capable 
of withstanding the widest ranges of heat and cold and of peopling the 
world from its tropical deserts to its polar wastes ; and to endow him with 
a brain by virtue of which he has made himself master of the earth and all 
its living inhabitants ; it has taken no less time for the evolution of the 
many factors without which his present success would have been impossible. 
To pick out a single instance, probably few things in the whole story of 
life have been more fruitful in effect than the appearance of the grasses 
in Late Eocene times, followed by their rapid evolution and spread in the 
Oligocene and under the direction of the critical events of the Miocene 
Period. Starkie Garrluer in an admirable paper first drew attention to 

C— GEOLOGY. 107 

the vital importance to the animal evolution of the world in general, and 
to the welfare of man in particular, of this step forward. It was followed 
by great changes in the insect world, by the rapid production of herbi- 
vorous maimnals endowed with speed, great migratory powers, special 
dental and other anatomical adjustment to the new foods, and the insti- 
tution in their herds of a disciphne, subordination, and leadership which 
are almost tribal. These last qualities were rendered doubly necessary 
by the consequent rapid development of carnivora, and the need for scrap- 
ping passive and even active means of defence in order to secure the power, 
speed, and reserve necessary to follow their food harvests over great 
stretches of country. At the same time the habits and instincts thus 
brought about were those which man, by domestication, has been able to 
turn to his own ends. Thus at a blow, as the outcome of this stage of 
Tertiary evolution, there became available for mankind not only his chief 
plant food and drink, his luxuries as well as his necessaries, but his chief 
animal foods, together with his aid from the speed, strength, service, and 
endurance of the animals which he domesticated and to which he assumed 
the position of leader of the herd. 

But while with the aid just described it was possible for mankind to 
progress far on the road of civilisation, progress would have been stopped, 
and as a matter of fact was seriously retarded, until the discovery and 
utilisation of the solar energy stored up in the earth's crust during the 
Carboniferous and subsequent Periods in the form of coal and other fossil 
fuels. The very exceptional conditions, climatal, geographical and 
botanical, requisite for coal formation, occurred all too seldom in 
geological history ; but it has so happened that few areas of the earth are 
devoid of coal belonging to one Period or another ; and the shaping of 
kingdoms and dominions has been such as to include supplies of fuel in 
most of them. Whatever may be the main sources of energy in the future, 
radiant, intratelluric, hydraulic, tidal, atomic, we have been largely 
dependent in the past, and probably shall continue to depend for many 
years to come, on that portion of the solar energy stored up by vegetation, 
and especially on that preserved in the earth-crust in the form of coal. 

But again civilisation must have been greatly hampered or driven into 
a different course but for the agencies which have sorted out from the medley 
of materials of which the earth is composed, simple compounds or aggre- 
gates of compounds, or in rarer cases simple elements, in such a form that 
they are available for human use without the expenditure on them of 
excessive quantities of energy. The concentration of metalliferous ores, 
salines, and the host of other mineral resources has made perhaps the most 
important contribution of all to the latest stage — in good and evil — attained 
by civilisation. 

Finally, doubt may be expressed whether man could have attained his 
present position if he had not made his appearance comparatively soon 
after a period of intense earth activity, when broad areas of newly raised 
sediment were available for occupation, when the agents of denudation 
and renewal were in active operation, and when a wave of rapid organic 
evolution was active. And a conjecture may be permitted that human 
evolution itself was probably hastened by the latest climatal severity 
through which the earth passed, the effects of which are only slowly 
passing away. 


Much of what has just been said may revive recollection of an old Swiss 
guide-book which praised the beneficence of Providence in directing 
the dreaded avalanches ' into the desolate and uninhabited valley of the 
Trumleten Thai and in sheltering from them the beautiful, fertile, and 
inhabited valley of Lauterbrunnen.' However, it is far from my intention 
to imply that ' everything is for the best in this best of all possible worlds,' 
but only to point out, in reviewing the long chain of events of which we 
see the present end-product in civilised man, that within the ken of 
the geologist there have been many critical stages in the earth's history 
when any marked change in the conditions which then prevailed must 
inevitably have reacted profoundly upon the development of the human 
race when at long last it stepped out from the lower ranks to take the earth 
as its rightful possession. 


A review of the history and present position of geology shows that its 
better-known services to mankind have been in relation to the foundations 
on which industrial development and modern civilisation have been built 
— the mineral resources of the earth. These are many and various, all of 
them explored by geological methods. In every application of them 
we are again brought back to the primal essentials — water, iron, and fuel — 
and it is in the discovery and exploitation of these that the services of 
geology have been of especial value. 

But in the course of the development of both the economic and the 
scientific sides of geology the principles discovered and elaborated have 
fertilised and enriched human thought as expressed not only in other 
sciences but also in the sphere of literature. As it has become more 
precise and is able to give a more accurate and detailed picture of the 
stages through which the earth passed during the long story unfolded 
by the study of the stratified rocks, it has shown that the earth, though 
only a minute fraction of the \'isible universe, has had a wonderful and 
individual history of its own. The keynote of this history is evolution, 
the dream of philosophers from the earliest times, now passed from the 
realm of hypothesis into that of established theory. 

We are able to watch the evolution of the oceans and continents, 
of the distribution of landscaj^e and climates, and of the long succession 
of living beings on the earth, throughout many millions of years. 
During these ages we see the action of the same chemical and physical 
laws as are now in operation, modified perhaps in scale or scope, 
producing geographical and biological results comparable with those 
of to-day. Hutton and Lyell discovered for us in the present a key 
to unlock the secrets of the past ; the history thus revealed illuminates 
and explains many of the phenomena of the present. 

And the outcome of it all is to endow man with a simple and worthy 
conception of the story of creation, and to fill him with reverence for the 
wondrous scheme which, unrolling through the ages, without haste, 
without rest, has prepared the world for man's dominion and made him 
fit and able to occupy it. 

I desire to express my thanks to Mr. G. W. Lamplugh, Professor E. W. 
MacBride, Professor W. G. Fearnsides, and Mr. G. S. Sweeting for kind 
assistance in the preparation of this address. 






' " But what was the creature like ?" I asked. " What like ivas 
it ? Gude forbid that we suld ken wliat like it was ! It had a 
kind of a heid ufon it — man could say nae mair." ' 

R. L. S.—The Merry Men. 

If I were asked to point out the main change in zoological thought since 
the last meeting of this Association in Canada, I should venture to say that 
zoological problems have become problems of control, and that control, 
from implying mere restraint, has come to mean ' quickening.' The being, 
well-being, and becoming of the animal in its world are no longer problems 
of statics, but of dynamics. The fabric of the animal body characterised 
by those traits and that orderliness that are revealed by genetic analysis 
is no longer regarded only as a link in the chain of organic affiUation, nor 
as a fact simply, but as the balanced result of controlled becoming or 
development. The factorial hypothesis and its corollaries convey this 
impression strongly. The results of ecological analysis, meagre as they 
are as yet, point to the same conclusion. Experimental morphology may 
be summed up in the word ' regulation.' Animal physiology shows the 
same dominant tendency. The results of tissue-culture show the existence 
of a process which enriches the body by enforcing it. The infinitely varied 
animal fabric appears to be the exquisitely balanced individual expression, 
of processes that quicken and restrain. 

This change from the older thought of the animal, as a mellowed, 
balanced product of changes under stress, has come from the renewed hope 
of understanding the natural problem in the new light of experimental 
analysis. If to succeed is to come up from below, the actual animal life 
that succeeds must be but a fraction of the submerged recessive life that 
experiment reveals. These recessives when artificially bred are no mere 
cripples, nor disconnected with the evolution of normals. They show us 
something of the depths of animal nature, and help us to realise that but 
for the grace of organic regulation we should be even as they. But the 
study of such analysis as a branch of zoology leads to an even more striking 
result. Not only does it reveal the existence of these sub-normals, but 
also it accounts for the defection of certain expected offspring. There 
are non-viable combinations of living substances. These entering the egg 
that should by expectation produce a male, render the egg incapable of 


development. That family will be one of daughters only. The existence 
and the control of lethal factors is one of the most significant discoveries 
of the underworld. 

It is with the results of one branch of this experimental study that 
I wish to deal. For several years experimental morphology has been 
actively pursued by zoologists in Europe and America. For the most 
part the egg has been selected as the natural point of departure, and the 
construction of the embryo or the development of the egg and of its parts 
has yielded results of great interest, though the search for a principle 
of organisation has not yet suceeded. To the developing organism it 
would seem to be all one whether it builds with one egg, with two eggs, or 
with a piece of an egg. (1) If there be any preformed or self-determined 
* organisation,' it may be shattered to bits without prejudicing the appear- 
ance of a normal embryo. The nuclei of the segmented egg may be shaken 
about as a bag of marbles, yet there will still remain the capacity for 
normal differentiation. It is therefore not surprising that there is as yet 
no unanimity of interpretation. Some investigators seek the explanation 
of development in an innate ' organisation,' thereby postponing by a 
process of infinite regress the attack on the problem. Others assume by 
an unconscious petitio 'principii the very problem they set out to solve. 
Others take refuge in a metaphysical solution, and lately the problem of 
' organisation ' has been regarded as an ultimate category that stands 
beside those of matter and energy. (1) 

Experimental zoology is a young science, and it is unlikely that we have 
reached Ultima Thule. Rather than regarding our position as one with 
our backs to the wall, I would ask leave to consider the report of the advance 
under the leadership of Professor Child of Chicago that has entered new 
territory. Instead of attacking the problem of the development of the 
organism from the egg, Child has long been working at the ' regulation ' 
of regeneration and organic development. From his analytical studies 
(2) and (3) he has arrived at certain conclusions that have far-reaching 
consequences. Though based on the behaviour of the lower Invertebrates 
and Vertebrates, these conclusions have already proved of wide application. 
I believe I am right in stating that no more fertilising biological idea has 
been disseminated in the last ten years than Child's hypothesis of metabolic 
gradients. It has captured the imagination of the younger generation of 
zoologists and is exercising an increasing influence upon them. 

The Individual considered as a Reaction System. 

It is no easy task to express the principles of Child's theory of the 
organic individual without reference to fundamental questions on which 
differences of opinion prevail, and about which our knowledge is incomplete. 
Perhaps the best way is to give a concrete instance taken from the fresh- 
water Planarians, those highly organised ' animated pellicles ' that divide 
by spontaneous fission. This process is initiated externally by a trans- 
verse constriction far down the parent body, but without any morphological 
distinction at this region. The tail-end after separation develops a new 
head, brain, eyes, and other organs. The head-end develops a new tail, 
and the process is eventually repeated. On turning up a stone in a stream 
running through limestone country one can find certain species of Planaria 
actively engaged in multiplication by this method. 


Child's work consisted in applying methods of physiological analysis 
to this well-known process. He found that before any external sign of 
constriction had appeared, the intact and apparently single individual 
showed a hump in the curve exhibiting the rate of chemical change in its 
tissues, when tested from head to tail. The maximum rate of change 
occurred in the head region, and then fell off gradually to rise again to a 
lower peak before the caudal fall. The site of the second, smaller peak was 
the site of the future constriction, and of the future head of the coming 

From this, and a large number of other experiments, Child concluded 
that the head of the parent exercised a variable degree of dominance over 
the subordinate individual that is represented by its own posterior end. 
External features were no longer the criterion of individuality, but merely 
the final expression of the physiological relation of dominance and 
subordination. The nervous system was but one expression of the embodi- 
ment of the dominant region (the brain) and of the track (nerve-cords) 
along which this region exercised its sway. This sway diminished in 
intensity with the length of the cords or distance from the dominant region, 
and it was this gradation of the influence of the ' head ' on the ' body ' 
according to distance that Child expressed as the ' metabolic gradient.' 
When the intensity reaches a certain minimum, those portions of the basal 
region whose potential is rising may assert their own hitherto suppressed 
individuality. They become almost physiologically isolated from the 
dominant region. The further conclusion therefore arose, that what we 
are accustomed to think of as an individual multicellular being becomes, 
when interpreted in the dynamic way, a composite being. The intact 
Planarian is only prevented from displaying its constituencies by the 
dominance of the head, but a number of circumstances may interfere with 
the dominance. As the head by growth of the body becomes removed 
from the tail region, the intensity of its influence wanes. If the conduc- 
tivity of the channel of influence falls, the same result ensues. Again, 
should the tail become the seat of growth, or assert its independence by 
increase of size or in other ways, then the influence of the head is negatived. 
In all cases the head action is positive and not merely inhibitory. In all 
cases the basal action on the head is not positive, but indirect or 

There are two special assumptions deliberately made by the author of 
this conception of organic individuality that require emphasis. The 
first concerns the independent nature of the apical region, the second the 
use of the term ' metabolic gradient.' The assumption with regard to the 
first is that the head or apex expresses the most intense and most intimate 
relation between the organism and its environment localised at one pole. 
Here the two are really one, and the head is the expression of this fact as 
a physiological, morphological and historic process. The other assumption 
is based on the physical basis of life as the seat of chemical changes and 
chemical correlation in which it is impossible to distinguish qualitative 
from quantitative effects, and asserts that controlled alteration in the rate 
of change (for example, of oxygen consumption) along definite gradients 
is the main ' cause ' of that structural and chemical correlation that we 
call the base. The head or apical region is thus, in a derivative sense, 
self-determined. It is the animal at its highest ; and as these largely 


self-determined changes appear always to lead in animals to the formation 
of a central nervous system if they go far enough, the conclusion is reached 
that the nervous system is the final expression, both in arrangement and in 
mode of action, of the system of metabolic gradients. 

A corollary of great importance can be deduced from the case of the 
Planarian. The degree of individuality of the daughter is a measure of the 
loss of control of the head-end, a not unfamiliar phenomenon. As this 
occurs, the daughter becomes more and more physiologically isolated and 
her metabolic processes proceed at a faster rate. Hence physiological 
isolation is a fundamental factor in asexual reproduction. 

The Development of the Frog Egg as a System of Gradients. 

In the light of this conception of the individual being as a reaction- 
system, we may now take the unfertilised ovarian egg, say of the frog, as 
a primary individual. It possesses an axial gradient. One pole is the 
region of highest metabolic rate determined by the relations of the egg to the 
maternal tissues and the other external agencies. There is evidence that, 
from this apical pole, chemical change proceeds in waves of decreasing order 
of intensity through the protoplasm towards the opposite or basal pole. 
Though there may as yet be no visible structural change in the colloidal 
medium, yet the factors that produce the first visible change are there. 
Difierentiation on this view is the expression of chemical change along the 
gradient. The cell or ovum is in fact a creature ' with a kind of a heid 
upon it — man could say nae mair.' 

The changes that ensue during the maturation of this egg or primary 
individual are too involved, and too familiar, to zoologists for me to 
enumerate. The little sphere, still without visible differentiation, becomes 
a stratified power-station. The apical pole remains chemically active, the 
basal pole accumulates stores of potential food and energy. The whole 
globular microcosm becomes enclosed in a non-permeable membrane, and 
is shut off as a closed system from the outer world. If only one of its 
extruded polar bodies returned ; if only something could break this too, 
too soUd envelope ; if only some messenger from the outer world, some 
Orpheus could visit the cold Eurydice, then development might begin. 
And it so happens. In the natural sequence, Orpheus — the spermatozoon 
— is the winged key that unlocks the imprisoned one. He casts a shadow 
— the grey crescent — that heralds the advent of the new gradient, the one 
that takes sides, and that prophetically unseams the germ from the nave 
to the chaps, that separates the right side from the left. As if to justify 
the use of emotional language, the germ at that moment of release takes 
an explosive breath sa though the crisis were over. It will never take a 
deeper one. The proscss of development is begun. 

The first trace of the embryo is the apical region or brain, formed as 
part of that region of greatest metabolic activity known as the dorsal lip 
of the blastopore, or the ' differentiator.' (4) This region provides the 
three co-ordinate lines or ' metabolic gradients ' along which the main 
features of structure are elaborated— the primary gradient along which 
the central nervous system forms ; the secondary gradient for the axial 
organs ; and the transverse gradient along which the lateral organs are 

^ D.— ZOOLOGY. 113 

The fate of the cellular material with which the difEerentiator deals 
depends not on their pre-determined nature but on the changes they 
undergo in passing to their final place in the organism, and to the company 
they keep when they get there. So far as their fate is concerned they 
may say with Hamlet ' the readiness is all.' In the hands of the three 
co-ordinate gradients that radiate from the ' differentiator,' it matters 
nothing whether the cells they hand on to build the back or the side are 
those naturally presumed to fit the part. Cells that would under normal 
circumstances form skin cells on the outer surface, and that lie outside 
the reach of the differentiator, will if grafted into it become kidney-tissue, 
muscle-tissue, or gut-tissue. And the converse is true. Tissue of the 
differentiator itself, presumably destined to become kidney or muscle, may 
be grafted into the wound left in the skin by the previous excision, and there 
it will become skin. So the surface tissue that would become brain if left 
alone will, if grafted into the differentiator, become intricately involved, 
and after travelling inwards and forwards find itself transformed into the 
likeness of those with which it is now a companion in function. With 
increasing zest we may repeat Huxley's great metaphor concerning the 
cells of the early embryo : ' They are no more the producers of the vital 
phenomena than the shells scattered along the sea-beach are the instruments 
by which the gravitative force of the moon acts upon the ocean. Like 
these, the cells mark only where the vital tides have been and how they 
have acted.' 

The events that I have briefly described constitute the prelude to two 
other phases through which the life of a multicellular animal passes. We 
may call them collectively the indeterminate, the determinate, and the 
integrated phases. During the first, the three waves of chemical activation 
assort the cellular material along the axis of the body and next determine 
irrevocably its fate as organs of the individual. This period begins in the 
frog with the closing of the blastopore and of the neural groove. From 
now onwards the evolution of the organs proceeds from determined begin- 
nings impressed upon the constituent cells by their relation to each other 
and to the gradients. Remove the rudimentary organ from its normal 
position — the heart, the kidney, and the brain — and it will complete or at 
least continue its evolution even in the solitude of a moist chamber. But 
under normal circumstances this phase of organic determination leads 
insensibly to that condition of full and inter-related activity that we may 
call integration. The muscles may be able to develop apart from the 
nervous system, but without organic contact with that controlling system 
they cannot function. The kidney may exhibit characteristic complexities 
of origin and evolution without the aid of humoral or hormonic influence, 
but it cannot function apart from these. The primary factors of life — the 
metabolic gradients — are supplemented by new structural factors and new 
chemical factors, and together constitute personality. 

Meanwhile, the inevitable price, senescence, is paid for advance. The 
stream of animal life, unlike its prototype, sedimenting most elaborately 
where it runs most strongly, is running down. Stability of construction 
brings the penalty of diminished dynamic activity, and the advent of 
puberty marks for many animals the shadow of the fell sergeant. But 
life has still its reserves, or at least one means of continuing the life-cycle 
in its descendant, if not in its undivided personality. In those lower 

Jl»24 I 


animals of ponds and streams, the Planarians, the act of procreation can be 
both naturally and artificially checked, and a return to a less highly organ- 
ised state can be induced. In a similar way the act of sterilization induces 
fresh vigour in some of the higher animals. Finally, in many animals the 
body undergoes periodic retrograde evolution, renews its youth, returning 
to an undifferentiated state in which it passes the winter with heightened 
powers of resistance, and on the advent of spring redevelops its 

Evidence for the Hypothesis o! Metabolic Gradients. 

(A) Axial susceptibility. 

The evidence for these far-reaching conclusions as to the nature of the 
living organism is partly direct and experimental, and partly indirect and 
observational. The direct evidence has been drawn from experiments 
by Professor Child and his school on Protozoa, Coelenterata, Planarians, 
Liver-flukes, Annelids, Echinoderms, Fishes and Amphibia extending 
over about fifteen years. Recently Dr. Shearer (5) has repeated these 
experiments on the chick and on earthworms, with results entirely confirm- 
ing the conclusions of Child and his pupils. A critical review of the evidence 
has recently been published by Child and Bellamy (5a). 

The first class of evidence relates to axial susceptibility to the action of 
toxic or narcotic substances. When immersed in, for example, a weak 
solution (0.001 mol) of potassium cyanide in well-water, the ' head-end ' 
of the whole animal or the apical pole of the egg is the first portion of the 
body to undergo disintegration, and this is followed by a succession of 
stages during which the process slowly spreads downwards. In general, 
the susceptibility-curve plotted on the basis of time-ordinates against these 
stages as abscissae, shows a much sharper fall for young than for older 
animals of the same species if the solutions are above a certain degree of 
concentration. If very dilute solutions are used, the opposite result is 
obtained. Immunity is gained more rapidly by the young than by the old. 
These results may be explained as due to the action of the cyanide on the 
oxidation-process and possibly also on the physical character of the 
colloidal protoplasm. The important point is the definite relation of 
disintegration to the animal's axis. The ' head-region ' or the apex of the 
egg disintegrates first and the basal region last. The evidence therefore 
tends to show that the susceptibility gradient is evidence of the existence 
of a metabolic gradient. 

Estimations of this kind have been made by the use of a large number 
of narcotics and poisons and the results have been confirmatory. More 
recently, other methods of testing the presence, course, and strength of 
these gradients have been devised. Dr. Tashiro (6), for example, has applied 
to the nerves of the body an exceedingly delicate test (the Tashiro 
biometer) for the estimation of carbon dioxide in minimal quantities, and 
has shown that a gradient exists following the direction of the impulse 
along the nerve. Again, Child himself, and later Shearer, have demon- 
strated the presence of axial gradients in starfish and chick respectively, 
by the use of acetone and other substances, which are precipitated in the 
tissues of the living developing animal by oxidation, thus giving an ocular 
demonstration of the track of the primary gradient. Unquestionably 

D.— ZOOLOGY. 115 

the development and application of biochemical methods will indefinitely 
increase the weight of this testimony, but the main thesis appears to be 
established, namely, that there is direct evidence of the presence of a 
primary metabolic gradient along the major axis of the body. 

The indirect evidence is more easily appreciated by the general body of 
zoologists, and it is of the greatest interest. If the value of a hypothesis 
consists in the number of phenomena that are subsumed under it, then the 
gradient hypothesis on morphological evidence alone may take high rank. 
Old-established facts acquire new meaning. 

The general succession of cellular events iu animal development shows 
that the fertilised egg has a radial or bilateral symmetry before it exhibits 
cell division. Normal and experimental evidence point clearly to the 
conclusion that the first act of morphogenesis is the establishment in most 
animals of the head end, and in Coelenterates of an apical region. This 
is followed by the development of the dorsal surface in Vertebrates, and of 
the ventral surface in most Invertebrates, determining in each case the 
foundations of the nervous system. Simultaneously the lateral organs are 
laid down usually in the form of ' segments,' the outer part of which remains 
more embryonic and plastic, whilst the inner part, abutting on the axis of 
the embryo, undergoes more rapid and elaborate morphogenesis. The 
whole process of the gradual establishment of the primary rudiments of 
bodily structure in the embryo is not only consistent with the theory of 
gradients, but receives (perhaps for the first time) a rational ' explanation.' 

(B) Regeneration. 

Perhaps even more suggestive than the facts of individual development 
are the conclusions of experiment, both natural and artificial, upon the 
regeneration of animal organs and tissues. The main facts as to the 
extent and occurrence of the faculty for renewal of lost parts by animal 
tissues are well known, and need not be traversed here, but there are some 
special cases that are little known, and that form a test of the validity 
of the gradient hypothesis. Moreover, as this view grew out of the con- 
sideration of data given by the regeneration of animals, it is appropriate 
that this large body of analytical work should receive mention. 

Child's work, and that of his pupils, has shown that in certain freshwater 
Planarians, only experimental difficulties set a limit to the minimal quantity 
of the body that will regenerate the whole. If and when these difficulties 
are overcome, it is probable that a single isolated cell of many of the lower 
animals may be induced to regenerate the whole, as is the casein many plants. 
We are only at the threshold of these inquiries, and the progress of tissue- 
culture, which is now being actively pursued, will undoubtedly open up 
new ranges of control over the technique of physiological isolation. It will 
be remembered that H. V. Wilson and J. S. Huxley (7) have shown that 
from the artificial fragmentation of a sponge or hydroid, new individuals 
arise. From a few of those fragments — sheddings composed of cell- 
groups, and even a few isolated cells placed in suitable conditions — there 
arises by cellular conjunction a small amorphous mass, which acquires 
polarity and difierentiation, and forms a new sponge or hydroid, recalling 
the reconstitution of ' an exceeding great army ' in Ezekiel's vision of the 
valley of dry bones. We seem driven to the conclusion that every cell 
of these animals only develops a portion of its potentiality when actively 


functioniug as a part of tlie whole, and that each cell has in addition the 
opposite faculty of dedifferentiation — of becoming young and resistant at 
the same time. When this rejuvenated cell develops either singly or in 
company with other dedifferentiated cells, the resultant in either case 
exhibits a new metabolism and a new orientation, giving rise to an organ- 
ism with typical arrangements of dominance and subservience of parts, 
such as characterise all normal animals. 

The morphology of fixed colonial animals such as corals acquires fresh 
interest when considered in the light of this principle. Wood-Jones (8), 
as Child has pointed out, has found from a study of living Madrepora 
under natural conditions, that there is an apical radially symmetrical zooid 
at the top of the stem which give rise by budding to bilaterally symmetrical 
lateral zooids. These, however, do not bud off others so long as the apical 
zooid is present and active, until by growth of the whole ' shoot ' they 
become separated bv a certain distance from the dominant apex. W^hen 
that occurs, one of them becomes transformed into a radial member, puts 
out lateral zooids and becomes a new apex. If the apical shoot and stem 
are removed, several branches may arise by transformation of bilateral 
into radial reproducing zooids. The whole process so strikingly recalls the 
fundamental relations of dominance and isolation leading to organic repro- 
duction in animals and also in plants that Child does not doubt the general 
applicability of the principle to organisms in general. 

(C) Independence of the Apical Region. 

One of the most striking pieces of evidence on the subject of regeneration 
is the work of Ivanov on certain sea-worms, Spionids and Serpulids. 
Unfortunately, the greater part of the work (1912) is in an inaccessible 
Russian dissertation (9), but the first part oiE it appeared in 1908 as a 
continuation of his earlier researches on Luinbriculus, a fresh-water worm. 
In order to make the results clear, reference must be made to Ivanov's 
division of the AnneUd body. By reason of certain peculiarities of the 
mesoderm of the anterior segments, he accoimts as cephaUc, or, as he 
later calls them, ' larval ' segments, not only the prostomium and peristo- 
mium of zoological nomenclature {i.e. the apical and sub-apical segments), 
but those which follow, so long as they possess certain mesodermal 
characteristics. The rest of the body he calls ' post-larval.' This post- 
larval body is specialised in Serpulids into a thoracic and an abdominal 
portion. If now ' the head ' or three larval segments of Spirographs be 
removed, the process of regeneration is no simple or direct operation, but 
resembles, to a remarkable degree, the embryonic development of these 
segments ; whilst the regeneration of the body-segments proceeds in a 
different way. but also along the lines of the embryonic development of 
that region. What, however, chiefly concerns my argument is the establish- 
ment of a new head, not by morphollaxis (dedifferentiation followed 
by reconstruction on a new type), but by the appearance of an apical plate 
typical of the trochosphere stage, of pre-oral antennae (which have dis- 
appeared from the Serpulid trochosphere), and of the cerebral ganglia by 
thickenings that correspond to the ciliated pre-oral bands of the trocho- 
sphere. The interior of this dedifferentiated thoracic end of the decapitated 
body is now filled by immigration of ectoderm cells that assemble in three 

D.— ZOOLOGY. 117 

groups or segments, one of which gives rise to the corona so typical of 
Serpulids. In the meanwhile, the posterior part of the body is reconstituted 
into thorax and abdomen. 

It is most desirable that these results should be fully tested on fresh 
material, but taken in conjunction with the work of Allen on Procerasfea 
(10) and of the many workers on Lumbriculus, they point to the special 
nature of the apical segments of the body. Allen has shown that each 
batch of four or five segments taken from different portions of this Poly- 
chaet reorganise the whole, in such a manner, that the initial segments 
occupy the same relative position in the regenerated worm that they did 
in the parent animal ; and Ivanov has shown in Lumbriculus, that the 
histological development of the seven anterior ' head ' segments follows 
a different course from that of the rest. Child has concluded from his 
studies on Planarians ' that the head which appears in the reconstitution 
of a piece is not physiologically part of the piece and is not formed by 
the piece, but develops, so to speak, in spite of it.' (2. p. 113.) This is a 
hard saying, but we may bear it, if the facts I have given as to the process 
of head-formation in Polychaets are borne in mind. They show that the 
metabolic and morphological changes evoked by section are not those 
characteristic of the neck region in which they arise. They pursue a 
course of their own analogous to that followed by the normal pre-oral or 
apical lobe, and produce a complex structure in which the brain appears 
as a new development ; whilst further back the new differentiator leads 
to the independent new formation of the mesoderm of the thorax and 
abdomen. The whole process is strikingly reminiscent of the two similar 
lines of metabolic activity in the embryo of the worm or of the frog, and 
constitutes confirmatory evidence of the existence of a co-ordinated system 
of gradients. 

A peculiar corollary arises out of a consideration of animals that may 
possibly present two apical regions at opposite ends of the major axis. I 
venture to suggest that Lamellibranchs might prove unusually interest- 
ing if examined from this point of view. It is also possible that Cestodes 
would give interesting results, especially in the case of those irregular 
growths known as Sparganum. One of the virtues of this hypothesis is 
that it makes old things new and suggests new problems for investigation. 
Above all, it has led to the power to predict and control the results of 
experiment on two groups of animals, the OUgochaetes and the Planarians. 

Summing up the evidence adduced in support of the ' gradient hypo- 
thesis,' I am inclined to regard its value as indicative rather than demon- 
strative of that hypothesis, as its suggestiveness exceeds, in my opinion, 
its conclusiveness. Above all, this hypothesis suggests, and suggests per- 
haps for the first time, a method by which the problems of development 
can be linked up with those of genetics. 

Periodicity as a Fundamental Mode of Action. 

The animal according to this view is a system of periodic change. The 
system, as a whole, tends to slow down, but each part of it, each organ, 
works in shifts which permit every working group its period of rest. While 
resting, their capacity for output is increased, and on working again their 
rate of metabolism rises, falling again as the function progresses. Cycles 
of activity and morphological cycles are essentially age cycles. In the 


higher animals, the organism as a whole becomes, under conditions of our 
present imperfect control, irrevocably older, and each cycle of rest brings 
with it less rise in metabolic rate. In the lower animals and in hibernating 
members of the higher forms, extensive rejuvenescence takes place. The 
senile effect is indefinitely postponed. Physiological isolation of a part 
occurs from various causes — increased growth and relatively decreased 
subordination to dominance, position off the line or beyond the main force 
of the gradient. Such isolated regions re-acquire the higher rate of meta- 
bolic change, and establish a new gradient system or a renewed system 
based in either case on local differences in rate of stimulus. Such physio- 
logically isolated pieces we call germ-cells, buds or spores, but there appears 
to be complete gradation between the rhythm or cycle of rest and activity 
in the functional units of an organ, and the periodic ripening, discharge and 
activation of ova or the periodic production of medusae and of resting stages 
of Polyzoa or Sponges. To use Professor James Johnstone's phrase, the 
tendency of the universe to run down, or of entropy to increase, is opposed 
by phases in the cycles of life. The alternation of the physiologically 
younger state with the more highly differentiated older state is fundamental. 

Periodicity in Organic Function. 

Intimately connected with the idea of the organism as a synthesis of 
co-ordinated control is the principle of periodicity in the functioning of 
organs. This is a development of an old idea and is widely recognised by 
physiologists and pathologists. It may be expressed in the phrase that 
at any time the organism or any part of it, is a function of its own cyclical 
period, or, as I have just expressed it, an animal works its organs in shifts. 
What the shift-unit may be for each organ we do not know ; we do know 
that, for the higher animals, more tissue exists than is needed for well-being 
under average circumstances, and that when a time of special stress ensues 
the emergency is met, not so much by increasing the pressure on the work- 
ing shift, as by calling up the reserves and throwing them into the general 

The evidence for ' partial activity,' as the pathologists call this economic 
exercise of function, is partly direct, by tests indicative of activity or 
repose, and partly by the results of observation on the removal of organs 
or parts of organs. The glomeruli of the mammahan (rabbit) kidney 
have, by suitable means, been made to show their fields of activity at a given 
moment, and the result shows patches of active glomeruli alternating 
with inactive ones. Again, removal of a large portion of the liver is not 
necessarily fatal to man, nor is it essential that both kidneys should be 
present. Removal of one of the kidneys and a study of the after-effects 
confirms the conclusion that one kidney can do the work of both, and that 
a much smaller liver than is normally present can sustain the body in 
health. Similar conclusions apply to other tissues, and there is great need 
for the extension of research on these lines to the partial activity of animals. 

Two considerations of great practical importance for our present study 
of control as a principle of organisation arise out of an analysis of this 
view of cyclical functioning of parts of an organ. The first is that the rest- 
ing|shift is receiving less blood and is more resistant to disease than when 
it is working. It is in a state of less active metabolism,[and while recovering 

D.— ZOOLOGY. 119 

from the effects of its spell of work has become temporarily physiologically 
younger. The second consideration is that the age of the animal counts 
as an important factor in the final result. The removal of one kidney from 
an adult throws the entire excretory function on to the other, and thereby 
increases general susceptibility to disease or breakdown where previously 
only local susceptibility occurred. But in the case of a child the result is 
quite different. In this case, the remaining kidney develops its reserves, 
forms additional tubules and glomeruli, and ultimately attains a volume 
equal to that of the two original organs. It is thereby enabled to continue 
its action on the lines of partial activity, and to afford each of its functional 
units their periodic phases of activity and repose. I trust that I may be 
pardoned for taking a leaf or two out of the book of pathology for the purpose 
of illustrating, not only the principle of control, but also the great benefits 
to biological sciences that will accrue by a fuller mutual recognition of the 
advances made by pathologists and zoologists. 

Nervous Control. 

Another outstanding example of the working of control in the organism 
is afforded by the progress of neurology, in which your own earlier nomin- 
ated President and the President of Section I for this meeting have taken 
such a prominent part. The brain of man is now regarded as a hierarchy 
developed for control. The existence of its members, their activity and 
degree of suppression or of dominance and subordination, as well as their 
intricate relations to the body and its environment, are matters of interest 
to all of us, and their consideration may fitly introduce the larger aspects of 
control with which I shall presently deal. The brain is, in fact, the highest 
expression of the activity of that co-ordinated system of metabolic 
gradients which integrate the physical basis of life into individual being. If 
I may venture for a moment into these deep waters, it is rather to illustrate 
the existence of control than to expound that relation of the nerves to the 
gradient hypothesis upon which Professor Child has recently issued 
a special memoir (11). 

The well-known experiments performed on the arm of Dr. Head, and 
since repeated by others, revealed more fully than before the normally 
suppressed nature of the thalamic complex. The acute but uncritical 
sensations that he experienced during the return of sensibility — the proto- 
pathic form of sensation — represent in all probability an early stage in the ' 
sensations of vertebrates, and one connected with the optic thalami as that 
primary group of centres in the stem to which all sensory impulses con- 
verge. The subsequent return of normal epicritic sensibility marked the 
relative suppression of the thalamus by the higher cortical centres in the 
neopallium. The experiment caused a release of suppressed function. The 
lower order of the hierarchy was, for a time, allowed to exercise something 
of that disorderly, acute, and uncritical sensibility which has been in part 
incorporated into, but largely suppressed by, the more critical and dominant 
centres of the cortex. In some such way, the control that civilisation exerts 
upon society is thrown off by its retrograde units who indulge in dis- 
orderly, acute, and uncritical actions until forcibly restrained from so doing 
by the higher powers. 

In connection with the subject of nervous control and the development 
of social life, I should like to draw attention to the social insects whose 


activities have lately been reviewed by one of the most scholarly entomo- 
logists of the day, Professor Wheeler. In his new book on the subject (12), 
Wheeler mentions, without, however, stressing the significance of the sub- 
ject, that the advance from the solitary condition (that is, a pair of wasps, 
bees, or beetles making separate nests) to the social state is associated with 
two factors. First, the mother does not, as do the solitary forms, die after 
oviposition, but in virtue of special food she is able to survive the birth 
of her offspring ; and secondly, and more significantly, she touches them 
and they touch her in the act of feeding. It is this touch of nature that 
seems to make real kinship between mother and offspring, and that 
provides the starting-point for the development of that highly specialised 
group of societies into which insects alone have the entree. It would be of 
the greatest interest to make a comparative study of the nervous system 
(particularly of the brain) of those bees, wasps, and beetles that exhibit the 
first touch of social genius. In its more advanced forms, control exercises 
the most diverse influence upon the whole economy of the insect society 
that practises it, one of the most curious being the control of the digestion 
of a specialised article of diet (wood pulp) by the Flagellates that live 
symbiotically in Termites. Termites have apparently discovered and 
exploited the cytolytic ferment that these Flagellates exert, and by a 
process of rectal feeding of their own young they ensure that each larva 
is provided with the necessary digestive ferment. 

The Control of Environment. 

The organism, however, does not exist except as relatedness. We are 
too apt to abstract it as a concept from its inner environment and from 
its setting in the outer environment which are really part of its being. 
The acid test of this proposition is the mature but unfertilised egg. As I 
have pointed out, this microcosm is a system of readiness for complex and 
energetic development, but is without contact with the outer environment. 
It is a closed system. It is physically as well as physiologically alone in the 
world. It hovers between life and death. As a (physiologically) highly 
differentiated system, formed late in physiological history of the individual, 
it is what Child calls a senile cell. Tested by the susceptibility method, by 
respiratory exchange and by heat production, the mature egg of most 
animals is inactive, and, in contrast to the rate of change it will exhibit if 
fertilised, may be said to be inert. If now this closed static system is put 
in relation to the outer world, the response is immediate. Drastic changes 
convert the static into a highly dynamic system, A dynamic relation 
between the egg and its environment is then a necessary condition for the 
initiation of development, and the ' environment ' of later stages is but 
an elaboration of the ' relatedness ' opened up by fertilisation. 

The internal or humoral environment, elaborated by the organism 
and controlled by its hormones, forms one of the ' normals ' of 
the higher animals. This chemical correlation is associated with the 
acquisition of external normals largely but less surely independent of 
changes in the outer world. The place in nature, the environment that 
has become, as it were, part of the organism — constancy of temperature, 
steadiness of balance in the face of altering conditions — is gained pari 
passu with the establishment of normals of internal environment. Regu- 

D.— ZOOLOGY. 121 

lation of its place in nature, ' choice ' of environment (including the 
presence of other organisms as well as the conditions of life in the restricted 
sense), adherence to a selected field of outer impulses, constitute an 
essential feature in that relatedness which constitutes individuality. ' 1 
am part of all that I have met.' 

A few illustrations taken from recent ecological work may not be un- 
welcome. Mr. Eliot Howard (13) has concluded that spring migrants to 
England each after their kind select and guard a territory on their arrival. 
The distinctive song of the cock announces this achievement to the later 
flight of silent passing hens, and mating is but a prelude to a continuous 
policing of the stretch of hedge, area of moor, or piece of covert whose 
boundaries, to us invisible, are clear to them. The intrusion of another 
cock of the same species is hotly resented, and fierce engagements, extended 
it may be, to the cocks and hens of other species, are continued, up to the 
boundary and then suddenly cease. The bird and its environment — the 
territory — have become one activity, and it is restless till it has established 
itself in its niche. Just so, to take a more familiar example, each member 
of a Council or Parliament at each sitting has to regain his orientation 
both to place and to person before he can be at rest and at his best. 
As J. S. Haldane has put the matter, ' regulation of the external en- 
vironment is only the outward extension of regulation of the internal 
environment . . . An organism and its environment are one ' (14, 

If we now apply the principle of physiological isolation to the organ- 
ism as influenced by, and influencing, its external environment, many well- 
known facts of zoological distribution become intelligible. Isolation arises 
from many different causes — by isolation by growing size, by decrease 
in conductivity in the path of transmission from the dominant region, 
by decrease in dominance itself, or to a change in the conditions of life — 
and no general statement can be made that will cover all cases. 
Bearing in mind, however, that life under dominance tends to exhaustion, 
whereas isolation leads to the renewal of activity at a lower level of 
complexity, we should be prepared to find that organisms change their 
environment with change in their physiological conditions, and that 
historically there would be ' backwaters ' of those stocks that represent 
ancient stages of more progressive races ; and we should further expect 
that these ' islands ' would possess a higher metabolic rate than the more 
differentiated and highly integrated races. To them rather than the domin- 
ant races we should expect the future to belong. From others, like them 
externally perhaps, we should expect neither progress nor repression, but 
a balance that, indefinitely perhaps, postpones the evil day. 

These relations we do find. The indefinite persistence of Lingula and 
Nautilus on the mud flats and depths of the Fijis in the Far Eastern seas, 
of Pleurotomaria in the Far East and West, the general isolation of ' living 
fossils,' is on this view to be regarded as a balanced senescence. Even in the 
most progressive regions of the world there are islands or backwaters 
where such arrested balance maintains a precarious existence. Proteus 
and other primitive forms survive only in the Balkan peninsula. Primitive 
societies of mankind or primitive customs likewise survive in those isolated 
communities of a progressive race. Modern industrialism creates such 
islands where the raw material or the worlring conditions demand isolation 


from the larger towns, and in this way acts favourably to the biological 
future of the island communities. 

The question as to what determines or inhibits the ' progressive ' 
development of an isolated animal or human group, provided as it is with 
an actual or potentially higher metabolic rate than that of its more 
dominated portion, is a question of the greatest interest. In so far as 
isolation leads to greater ' individuation,' we may look to the isolated as 
the source of fresh individuality and power to wield dominance, to be paid 
for in time, however, with the inevitable price of diminished progress. 
A careful survey of closely allied species in certain groups of animals 
(Fishes, Echinoderms) has shown that the nearest allies of a given species 
occupy widely separated areas. Thus, the common European Starfish has 
its nearest ally on the opposite coast of Canada and America, and the sea- 
urchin. Echinus esculentus, has its nearest ally in blood far removed in space. 
Canada and Scotland might serve as a typical example. Just as conditions 
of existence form one of the factors governing isolation, so the readiness to 
make a change of function in ' adaptation ' to a consensus of favourable 
conditions may determine the advance. The heightened metabolic activity 
of the isolated ones may then profit by the new environment which they 
incorporate into their new individuality. 

Professor Elliot Smith has emphasised this view of the origin of 
civilisation. If, as we all hoped, he had addressed you, I venture to think 
that in his mind, if not expressed in his words, would have been that 
thought ' the readiness is all.' Many tides in the affairs of men may have 
washed the islands of the strong isolated groups before their concurrent 
benefit was grasped and developed. Egypt and Western Asia was not 
the only area where the earth would have seen the birth of civilisation, 
but elsewhere, perhaps, the/readiness was lacking even if the physiological 
impetus was stored in the biological history of the people. So it may 
have been with the history of animals and so it may be in the future. 
' In the reproof of chance lies the true proof of men.' Yet chance has 
other gifts than harsh reproof. 

Zoology as a Factor in Civilisation. 

When we consider the principles of periodicity of regulation in form 
and function, and of that characterisation of successive generations 
which constitutes genetics, we cannot help concluding that, so far as they 
are fruitful in stimulating inquiry and true to the best of our limited 
critical knowledge, they should serve to a much larger extent than is now 
the case in human thought and endeavour. I am not now referring to such 
knowledge as having merely a pragmatic sanction. Usefulness is not the 
justification for the study of biology. Wisdom is justified of all her children. 
It is because we are the outcome of the biological process that a science of 
life will provide men with a truer understanding. Biology in the Greek 
sense will be founded on the biology of science. 

Such recognition of its basal position has not yet been obtained by 
biology. The progress of industrialism, the application of physics and 
chemistry to national needs and national entertainment have won, for 
physical science, an appreciation and a belief which, even if unreasoned by 
the majority, has, I believe none the less, that sanction which gives weight 

D.— ZOOLOGY. 123 

to convinced public opinion. Nor are there wanting those who look to the 
development of physical science, alone or in the main, as the lodestar 
of modern civilisation. They may point out that even in those industries, 
such as animal and plant husbandry, that are most biological in character, 
the subject-matter so far as it is biological is dealt with in an empirical 
way, untouched by modern biological principles. The selection of new 
varieties, and the whole process of animal breeding in the world of racing 
and agriculture, is a cult now as always entirely cut off by science, but 
possessing the vigour and initiative that physiological isolation confers. The 
real ecologists are those — the fishermen, hunters, trappers — whose wonder- 
ful empirical knowledge and nomenclature contains more than can be 
reduced to the dimensions of that bed of Procrustes, our formal science of 
animal life. The advocate of physical dominance might even go further, 
and suggest that just in as far as modern civilisation had spread, to that 
extent had biological interests receded ; that the world of biological 
evolution, the natural faunas and floras of the unmastered spaces, were 
bound to succumb to the dominance of civilisation ; and that unless the 
biologists take heed, their very material for study will be reduced from 
the irreplaceable and almost infinitely rich variety of the wild, to the 
monotony of the house fly and house sparrow, and biology will become a 
mere ancilla to medicine and gardening. 

The advocatus diaboli has put forth his pleadings. How is the counsel 
for the defence to state his side ? He can point to the need for taking the 
long view. He is convinced that man as man, and not as a temporary phase 
in an unstable scheme of things, is a biological creation ; that as part of his 
invincible faith in evolution, the study of the products of evolution will 
throw light on man's body, mind, and destiny. But just as dominance and 
freedom from dominance are creative but correlative, so the over-mastery 
of a dominant scheme, the tyranny of organisation may lead, after a period 
of effective differentiation to a slowing down of the national spirit. The 
reaction, the return to individualism, the principle of isolation as I have 
called it, is the natural result. The problems of social philosophy, even the 
problems of government and civil life — biology in the Greek sense — are 
illuminated by the principles of zoology, and if the flame is at present 
flickering, weak, with little pressure behind it, there are those in this and 
other countries who have faith in its future brightness. This light shining 
strongly in the west, is a rising star. The astronomer will be satisfied to take 
his pleasure in its understanding, but it will also pilot the way for those who 
in many countries have long wanted a lamp to their feet and a light to 
their path. 



(1) Wilson, E. B., The Physical Basis of Life (Yale Univ. Press, 1923). 

(2) Child, C. M., Individuality in Organisms (University of Chicago Science Series, 


(3) Child, C. M., Senescence and Rejuvenescence (University of Chicago Press, 1915). 

(4) Huxley, J. S., Nature, Feb. 23, 1924. 

(5) Shearer, Proc. Roy. Soc, London, B. vol. 96, 1923. 
(5a) Child and Bellamy, ibid., p. 132. 

(6) Tashiro, American Journ. Physiology, .33, 1913. 

(7) Wilson, H. V., Journ. Exper. Zoology (5), 1907 ; Huxley, J. S., Phil. Trans., 1912. 

(8) Wood-Jones, Coral and Atolls, 1910. 

(9) IwanofE, P. P. (' Regeneration and Ontogeny in Polychaeta '), Dissertation (in 
Russian), St. Petersburg, 1912 ; Zeit. wiss. Zool, 1908. 

(10) Allen, E. J., Phil. Trans. Roy. Soc, London, 1921. 

(11) Child, Origin of the Nervous System (University of Chicago Press, 1921). 

(12) Wheeler, W. M., Social Life in Insects, 1923. 

(13) Eliot Howard, Territory in Bird Life, 1920. 

(14) Haldane, J. S., Organism and Environment (Yale Univ. Press, Newhaven, 1917). 







I. The Modern Increase in Population ....... 125 

II. The Races of Mankind 127 

III. Geographical Principles ......... 128 

IV. Inter-Racial Relations :......... 129 

1 (a) Racial Fusion. 1 (6) Racial Fusion in South America. 

2 (a) Co-resident Distinctness. 2 (6) The Position in the United 

3 (a) Racial Segregation. 3 (6) The Probable Development in the 

United States. 3 (c) Segregation in South Africa. 

V. Tropical Colonization and the Future of Australia. .... 136 

1. Supposed Unfavourable Factors in Tropical Climate : 

(a) Heat. 

(6) Moist Heat. 

(c) Monotony in Temperature. 

{d) Actinic Rays. 

(e) Miscellaneous Influences. 

2. Medical Opinion. 

3. Improvements by Public Sanitation. 

4. Old-established European Settlements in the Tropics. 

5. The Development of Tropical Australia. 

(a) Vital Statistics in Queensland. 

(6) The Northern Territory. 

(c) Queensland and the Sugar Industry. 

6. Rate of Progress and the Drawbacks of the Tropical Climate. 

7. Conclusion. 

I. The Modem Increase in Population. 

The problem of the present century, according to many observers, is 
the problem of the colour line. We are warned from one side of the danger 
to civilization of the rising tide of colour ; and from the other of the peril 
to humanity from the rising tide of colour prejudice. The difficulties of 
the racial problems have been intensified by the unprecedented increase 
in the world's population. According to the estimates in 1696 of Gregory 
King, a pioneer in political statistics, the utmost population which England 
could support would be 22 million and that number would nob be reached 


until the year 3500 or 3600 — ' in case the world should last so long.' 
In the year 1900, according to his expectations, the population would have 
amounted to only 7,350,000. These egregious miscalculations are a 
warning of the uncertainty of statistical forecasts as to population and 
an illustration of its surprisingly rapid increase in the modern world owing 
to the application of science to commerce, industry, and public health. 
This accelerated increase is mainly due to the European race, but it has 
been most rapid in Africa and Asia in consequence of the reduction by 
European administration of internal war, plague, pestilence, and famine. 
From 1906 to 1910, to quote the latter half of the last normal decade, the 
population of the world grew at the rate of doubling in sixty years. If this 
rate were to be maintained the 6,600 millions 6i people, which it has been 
calculated is the most that the world can feed, would be in existence in 
120 years ; and even if the food supply were indefinitely multiplied by the 
precipitation of the nitrogen of the atmosphere as a constant rain of manna, 
standing room on the earth, exclusive of the remoter Arctic and Antarctic 
lands, would be all filled when the pojDulation numbered 700 billion (i.e. 
million million) in the year 3000. 

The rapid increase in the population of the world during the last half- 
century has had disturbing political influences. Thus many parts of 
India have apparently almost the maximum population possible iinder exist- 
ing economic conditions, and the slow jDresent increase is gained painfully 
to the accompaniment of irrepressible discontent. Countries which once 
had extensive empty lands have begun to close their ports to aliens, in 
obedience to the principle that each land must consume its own surplus 
population. The United States, the ' melting-pot ' where the mixed races 
of the Old World were being fused into a new type, has adopted measures 
based on the growing belief, in the words of Lothrop Stoddard, that ' the 
book of race migrations must be closed for ever.' The halt at Ellis Island 
has already warned eastern and southern Europe that America is no longer 
an open asylum for refugees. The three great natural outlets from Asia 
have been closed by the prohibition of immigration thence into western 
America, by the ' White Australia ' policy, and by the refusal of eastern 
and southern Africa to accept further Asiatic contributions to their 
needed enlarged sujjply of labour. The struggle for expansion, which 
was the ultimate motive of the World W^ar of 1914-18, will inevitably be 
still more bitter and terrible if it become a struggle for existence between 
the White and Coloured races. 

The effort bo foresee the future progress of the world raises two con- 
trasting visions. The increase in the wealth and prosperity of all the 
continents by the influence of the European race may be continued, either 
by colonization, as in America and Australia, or by administration, as in 
Asia and Africa. Asia, by improved industrial methods, and Africa, 
relieved from the slave trade, may continue to advance in co-operation 
with the European race instead of under its government : and European 
control may be voluntarily withdrawn as sympathetic alliance replaces 
the older systems of servitude. If those developments take place the 
twentieth century will be indeed a golden age. 

The alternative picture is darker. Europe, during the past fifty years, 
like Portugal in the sixteenth century, may have taken on tasks beyond 
its power. The drain on the manhood of Portugal by its vast colonial 

E.— GEOGRAPHY. 1 27 

empire reduced the home population by half, the land Avent out of culti- 
vation, the country was stricken by famine, and Negroes were introduced 
to till the derelict farms and then absorbed into the nation. The dilution 
of the Portuguese by Negro blood is often regarded as one of the main causes 
in the fall of Portugal from its former political, scientific and intellectual 
pre-eminence. Has Europe been led into the same enterprising but 
disastrous error ? Has it undertaken the administration of larger areas 
than it has the personnel to maintain ? Will, for example, the African 
troops in France have a similarly demoralizing effect as the Negroes in 
Portugal and the slaves carried into Italy during the decline of the 
Roman Empire ? 

n. The Races of Mankind. 

Consideration of inter-racial problems requires a classification of the 
races of mankind. The most popular classification is that into four races 
based on colour — the white or European, the yellow or Mongolian, the 
brown or non-Mongolian Asiatic, and the 'black' or Negro. These colour 
names, however, are only valid if used in a conventional sense, which is 
often inaccurate. 

The character of the hair forms a more reliable basis and it divides 
mankind into three primary races — the Caucasian, Mongolian, and Negro. 
The Caucasian has abundant wavy hair ; the Mongolian long, lank black 
hair ; and the Negro short woolly hair. This classification is only politi- 
cally suitable if the Caucasians be subdivided into two sub-races, the fair- 
complexibned people of northern Europe, who were named by Huxley 
the Xanthochroii, and the Dark Caucasians or brown people, the Melano- 
chroii of Huxley, who include the south Europeans, and some still dancer 
people in Asia and Africa. 

The numbers of the white, yellow, brown and black divisions of mankind, 
according to the returns for the last available year before the war, were^ 
white or European race 520 million ; Mongolian 620 million ; brown 
370 million ; Negro 190 million — total 1,700 million. The coloured races 
are in the majority of more than 2 to 1. The advantages conferred on the 
Whites by their more efficient organization, better equipment, and com- 
mand of transport and machinery should enable them to hold their 
own in any direct conflict, in spite of their inferior numbers. The danger 
to the white race comes from their dependence on trade with Asia and 
Africa which would be jeopardised by the restoration of the political 
conditions that held before those continents fell under European influence. 
The maintenance of European dominion lays a heavy burden on the white 
race, as it is responsible for the government of eight-ninths of the habitable 
land of the globe. One-third of the inhabitants of the world rule eight- 
ninths of it ; the remaining two-thirds of the people control only one-ninth 
of the land. 

This condition is modern. A thousand years ago the Whites held 
only part of Europe, for Spain was then ruled by the Moors and south- 
eastern Eiu-ope by Asiatics. Pour centuries ago the white race had 
secured nearly all Europe ; but the coloured races still ruled the rest of the 
world. The formula of Asia for the Asiatics and Africa for the Africans 
was then accepted, as well as America for the Red Indians. Even at the 
beginning of the last century only a small proportion of North America 


and a few small setblements in Africa and Asia were occupied by the 
Whites. During the last century, and especially since the development 
of railway and steam navigation after 1840, the whole of America, all 
Africa except Abyssinia and Liberia, all Australia, and all Asia, with the 
exception of China, Japan, and Siam, have fallen under the control of 
European people. Since 1900 European influence has, however, suffered 
extensive reductions in Asia and Africa, which have advertised the relative 
decrease in the number of white people. During the past half-century the 
unprecedented increase in the wMte race has been exceeded by that of the 
coloured people. Increased disparity in numbers means, in a democratic 
age, an inevitable transfer of power ; while the former prestige of the white 
man has been undermined by his own beneficent rule. Alike in war and 
peace the personal authority which the white man held in 1900 has under- 
gone a momentous decline. 

ni. Geographical Principles. 

Whether that movement is a temporary set-back or a permanent 
change in inter-racial relations is a problem on which Geography should 
afford the most reliable available guidance. If we accept the scope of 
Geography as the study of the earth with especial relation to man, its 
primary duty is to collate the results of other sciences which throw light 
on the major problems of human development. It should learn from 
physiology the effects of climate, altitude, and tropical sunshine on the 
different races of mankind ; from biology what diseases are due to para- 
sites and how infection may be prevented ; it should find from agriculture 
the most profitable local crops and how to improve the food supply; it should 
discover from geology the nature and distribution of soils and the available 
supplies of minerals and mineral fuels ; and it should seek from the ethno- 
logist guidance as to the characteristics of the races who are competing 
in the struggle for existence. The geographer provided with this knowledge 
should endeavour to weigh evenly, free from race prejudice and political 
bias, and undisturbed by the fears of vested interests, the factors which 
control the distribution of mankind. 

The ruling geographical principles as to the distribution of the three 
primary races may be summarized as follows : 1. The population must 
be scanty in the colder regions of the world owing to their long severe 
winter, and also in the dry deserts, except in those relatively small areas 
that can be watered by irrigation. 2. The tropical regions have hitherto 
been the home of the coloured races, while the white nations have been 
mainly restricted to the temperate zone. 3. When different races live 
side by side, the more primitive race, unless conditions be imposed on it 
fatal to its spirit, will outUve the other wherever the struggle for existence 
is keen. 

From these principles two main inferences can be drawn. First, 
the frigid zones, the chief deserts, and the tropical plateaus above 12,000 ft. 
or so above sea level will always have a sparse population, and will long 
be left except for occasional commercial, mining, and industrial centres, 
to the most primitive tribes who have access to them, such as the Eskimo 
in North America, the Lapps in Europe, and various hardy, easily contented 
Mongols in Central Asia. Second, white colonists have no chance of per- 


manently occupying land near the overcrowded parts of Asia or accessible 
to the fast multiplying Negroes of Africa. White merchants may find in 
these regions profitable trading centres and may for a time rule and ad- 
minister them ; but when white enterprise has subdued the land, built 
railways and utilized the rivers, the coloured man will oust the white from 
all but the few posts that require experts. 

IV. Inter-racial Relations. 

The relations of the white and coloured races living in the same land 
may be settled on any one of four lines — amalgamation by miscegenation ; 
co-residence without fusion, and with complete social separation ; the 
disfranchisement of the coloured population as State wards ; or the segre- 
gation of the different races in separate countries or communities. 

1. (a) Racial Fusion. — Amalgamation by complete racial fusion is often 
recommended as being either inevitable or desirable, or both. That plan 
is recommended by the improvements in stock and plants wrought by 
judicious interbreeding, and mankind may be expected to benefit by the 
same process. The great modern nations are of mixed origin, and their 
efficiency is doubtless due to the varied capacities inherited from their 
miscellaneous ancestors. Accordingly many authorities, such as Lord 
Olivier, anticipate the settlement of serious difficulties and the betterment 
of the human race by inter-racial fusion. Lord Olivier claims that mixed 
races are superior to those of simpler constitution. ' So far, then,' he 
says, ' as there survives in a mixed race the racial body of each of its parents, 
so far it is a superior human being, or rather, I would say, potentially a 
more competent vehicle of humanity ' (' White Capita), and Coloured 
Labour,' 1906, p. 22). H. G. Wells regards inter-racial prejudices as one 
of the worst of existing influences. ' I am convinced myself that there 
is no more evil thing in this present world than Race Prejudice ; none at 
all, I write deliberately — it is the worst single thing in life now. It justifies 
and holds together more baseness, cruelty and abomination than any other 
sort of error in the world.' Its strength he considers renders it impossible 
for two races to live separately and in amity side by side. ' Racial differ- 
ences,' he declared in an earlier statement,' seem to me always to exasperate 
intercourse unless people have been elaborately trained to ignore them. 
Uneducated men are as bad as cattle in persecuting all that is different 
among themselves. The most miserable and disorderly countries of the 
world are the countries where two races, two inadequate cultures, keep a 
jarring, continuous separation ' ('The Future in America,' 1906, p. 273). 

The benefits of interbreeding, according to many aiithorities, are limited 
to parentage nearly akin, though in such cases the advantages are well 
marked, as exemplified in Canada. Intermarriage in mankind, it is urged, 
should be restricted to nearly related people. Herbert Spencer, in a famous 
letter that was not published until after his death, declared that the inter- 
breeding of widely different types produces weak inferior offspring, with 
' a chaotic constitution.' This view has been supported by modern 
students of Eugenics. Major Leonard Darwin, in a letter to the members 
of the recent Imperial Conference (192.3), urged that ' theoretical reasons 
can be adduced for believing that interbreeding between widely divergent 
races may result in the production of types inferior to both parent stocks ; 

1924 K 


and that this would be the result of miscegenation is at all events a common 
belief.' Dr. J. A. Mjoen — who, according to Major Darwin, has made a 
long study of these questions and is ' an authority well worth considering ' — 
after detailed study of the Mongolian-Caucasian hybrids in Norway, reports 
that the children of these Lapp-Norwegian unions are inferior physically 
and mentally. He concludes from his investigations that ' crossings 
between widely different races can lower the physical and mental level.' 
He urges ' Until we have more definite knowledge in the effects of race- 
crossings it will certainly be best to avoid crossings between widely different 
races ' (' Eugenics Review,' 1922, vol. xiv, p. 39). 

Professor Lundborg, of the Upsala Institution for the Study of Race 
Biology, has adopted the same conclusion. He deplores ' hasty race- 
mixture between nations who, from a race-biological point of view, stand 
too far apart.' He declares that ' a mixture between nations who, from 
a race-biological point of view, stand high and others containing lower 
race-elements, such as gipsies, Galicians, certain Russian tribes, etc., 
is certainly to be condemned.' Lord Bryce has twice asserted the same 
conclusion. According to this view mongrels (the offspring of different 
varieties) should be better than at least one of the parents, while hybrids 
(the offspring of different species or primary divisions of mankind) are 
necessarily inferior to both parents. 

This doctrine cannot be regarded as established, but the strong intellec- 
tual aversion to such unions among the Teutonic people will doubtless 
prevent the adoption of race amalgamation between the Negro and the 
Whites in North America or of northern Europe. Opinion against this 
policy is hardening in the one country, the United States, where it might 
be expected to find most support. There, intermarriage between Whites 
and Negroes is illegal in most of the States, and opinion is against it on 
both sides, except in so far as it is welcomed by one section of Negroes 
who would tolerate it to overthrow the social restrictions imposed upon 

1 (6) Racial Fusion in South. America. — The system of Race Fusion has 
been followed in tropical South America, which is occupied mainly by a 
hybrid people. The intermarriage of Spaniards and Portuguese with 
Indians and Negroes has proceeded to such an extent that only a small 
uncertain proportion of the inhabitants are of pure European descent. 
The population of tropical South America is a mixed race with the exception 
of small clans in some of the cities of Ecuador and northern Peru. In 
most of South America there is said to be no more prejudice against 
the mixture of races in marriage than there is in Europe against that 
between different social classes. The limitation of marriage in South 
America is by class not by colour. 

' Everything ' in South America, said Bryce (' South America,' 1912, 
p. 565), ' points to a continuance of the process of race mixture.' ' Misce- 
genation,' says Garcia Galderon ('Latin America,' 1913, p. 356), 'is universal 
in South America between Iberian, Indian and African.' ' A single 
half-caste race,' he says (ibid., p. 338), ' with here the Negro and there the 
Indian predominant over the conquering Spaniard, obtains from the 
Atlantic to the Pacific ' and from Mexico to Patagonia. The predominance 
of the white race may be maintained in the southern parts, but most of 
South America seems destined to be the home of a hybrid Indo-Negro- 


Iberian race. South America illustrates the results of miscegenation on 
a continental scale. 

2 (a) Co-resident Distinctness. — The second available inter-racial 
development is by co-residence with the maintenance of racial distinctness. 
The greatest experiment with this policy is in progress in the United States. 
It is recommended there by leaders of both White and Negro opinion as 
the only solution of the inter-racial difficulties. Its most effective champion 
was the late Booker Washington, who is generally regarded as the greatest 
Negro whom America has yet produced. This policy aims at the associa- 
tion of the two races in work, but their complete social separation. Accord- 
ing to Booker Wasliington's famous analogy the two races should be 
separated in life as completely as the fingers, but as fully united in work 
as the hand. This idea attracted support from various sides, as it offered 
a practical basis for development, and involved the renunciation by the 
Negro, at least for a time, of his claims for political and civil equality. 
This policy is dependent on the better education of the Negro. Booker 
Washington, amongst his other titles to fame, was a pioneer in agricultural 
education ; and his institution at Tuskegee has undoubtedly done much to 
raise the status of the American Negroes. He has, however, been violently 
condemned by many of his compatriots, owing to his asserted surrender 
of their claims. According to these critics the advance of this policy has 
been attended by the lowering of the civil and political status of the Negro, 
and the intensification of inter-racial feelings by raising the jealousy of the 
southern Whites at his improved educational and financial position. 

The possibility of long continued associated distinctness by two inter- 
mingled races is contradicted, according to some authorities, by historic 
experience. Lord Bryce states that ' whoever examines the records of 
the past will find that the continued juxtaposition of two races has always 
been followed either by the disappearance of the weaker or by the inter- 
mixture of the two ' (' The American Commonwealth,' 1911, vol. ii, 
p. 532). Professor Kelly Mller, of the Howard University, Washington, 
expresses his conviction ' that two races cannot live indefinitely side by 
side, under the same general regime, without ultimately fusing.' A. B. 
Hart, Professor of History at Harvard University, is more hopeful, and 
he cites the long continued co-existence of Hindu and Muslim in India, 
of Boers and Kaffirs in South Africa, and of English and Indians in North 
America ; but these cases give no more encouragement to the prospects 
of Negro-Caucasian association in America than do those of the Jews and 

2(6) The Position in the United States. — Whether this policy is 
possible or not the testimony is overwhelming that the attempt to adopt 
it in the States has been attended by increasing tension and race bitterness, 
despite all the influences in its favour. 

Under the auspices of a Commission for Inter-racial Co-operation 800 
county inter-racial committees have been established. The two races 
have been uniting more often in educational and social work, both by 
informal association of neighbours, and by such organizations as the 
University Race Commission, the Southern Sociological Congress, the 
Rosenwald and Jeanes Foundations for the building of Negro Schools, 
the Phelps-Stokes Fund, the General Education Board and its Rockefeller 
Endowment, and by the munificent gifts of northern benefactors to 

K 2 


Hampton and Tuskegee. Moreover, the State Courts, by their decisions as 
to Pullman cars, have lessened the rigour of the regulations which separated 
white from coloured passengers on the railways ; and the Supreme Court 
of the United States, once regarded as unsympathetic to the Negro, has 
dismissed as unconstitutional some of the State laws that have been used 
to disfranchise him. Many circumstances favour the growth of more 
friendly feelings between the two races. 

Nevertheless, the general testimony of writers on the United States during 
the past twenty years is that the position has been, and is, going 
steadily from bad to worse. ' The two races,' says Professor Hart.'(1910), 
' are drifting away from each other and race relations are not improving.' 
A. H. Stone remarked in 1908 the increasing growth of race feeling 
among the Negroes. Lord Olivier in 1906 predicted that the policy 
which was and has been followed ' will doubtless in time bring about 
civil war.' William Archer, comparing the conditions in 1910 with 
those at the Atlanta Conference when Booker Washington put forward 
his co-residence policy, declares ' that the feeling between the races is 
worse.' W. P. Livingstone, a writer with West Indian experience, wrote 
in 1911 ('The Race Conflict,' pp. 13, 31) that the negro question 'remains, 
what it has been for a century, the darkest and most menacing cloud on 
the horizon of national life,' and that ' the situation is described as being 
worse to-day than at any time since 1865.' 

' Any competent observer,' said Maurice Evans in 1915, ' must see in 
the South, as in South Africa, a gathering storm, which means ultimately 
not only industrial war, but industrial war plus racial conflict.' 

The World War for a time appeared to improve the Negro position, 
owing to the labour shortage in the United States due to the stoppage of 
immigration from Europe and the urgent demand of the belligerents for 
munitions. But after peace the irritation of the Negroes at what they 
regarded as the systematic belittling of their war services and the friction 
due to increased contact in the cities led to serious race fights during 1919 at 
Washington, Chicago, Elaine, St. Louis, and Knoxville. These riots, 
with the determined defence offered by the Negroes, justify the insight 
of Livingstone's warning — ' So gigantic does the problem appear, so dijB&cult 
of peaceful solution, that the nation is helpless in face of it. It has become 
so subtly connected and interwoven with all the organic texture of the 
national existence that the people, as a whole, are afraid to make it a 
living question, not knowing what might be the result. There is an uneasy 
consciousness of the truth of the Southern warning, that the forces of the 
revolution, unspent and terrible, are ready at any moment to break out 
under sufficient provocation.' 

3 (a) Racial Segregation in the United States. — So alarming does the 
position appear that three drastic solutions have been proposed based on 
the separation of the Negro community by political disfranchisement, 
exile, or segregation. 

The first is the complete disfranchisement of the whole coloured 
population, including all with any appreciable proportion of Negro blood, 
and its tutelage under a special Board of guardians. The Negroes would 
have separate police and law courts, and separate schools in which the 
training would be mainly industrial. They would be wards of 
the State, and would elect representatives to their Board of protectors, 


but would have no votes for the Federal or State Parliaments. A plan 
for treating permanently a seventh of the population as irresponsible 
helots would appear utterly inconsistent with the American Constitution, 
and impossible in modern conditions under any democratic constitution ; 
and the Negroes, and especially the ' Near Whites ' who are predominantly 
white by blood, would regard the status proposed for them as an intolerable 

A second and still more drastic suggestion is the compulsory emigration 
of the whole Negro population to some such places as Hayti and Liberia. 
This solution was advocated by the distinguished American palaeontologist, 
E. D. Cope, and it was favoured by Abraham Lincoln until he was persuaded 
that the whole of the North Atlantic shipping could not remove a sufficient 
number to keep up with the normal increase in the Negro population. 
The scheme has been often rejected as impossible on the grounds that the 
American Negroes are too numerous for transhipment, and that there is 
now no available room for them either in the West Indies or Africa. These 
difficulties would not be insuperable if the United States were determined 
to overcome them, and the Negroes were willing to go ; for any such migra- 
tion would obviously have to be spread through a considerable period 
and neither the cost nor lack of room for the emigrants would be beyond 
the power of so wealthy and resourceful a nation. But the project is not 
worth discussion here, as the political difficulties place it out of court. 

An alternative segregation policy is that of collecting all the Negroes 
into one territory or State within the United States. That scheme might 
have been practicable in 1865 at the close of the Civil War ; but as the 
areas suitable for Negro settlement which were then available have been 
occupied, this proposal appears as much a counsel of despair as that of 
transplantation to Africa and Hayti. 

The only scheme of segregation within the sphere of practical politics 
is that for the assembly of the bulk of the Negroes in numerous scattered 
agricultural settlements where they would be withdrawn from close daily 
contact with the Whites, but would co-operate with the rest of their fellow- 
citizens in productive work. This agricultural ghetto policy would pro- 
bably lessen inter-racial friction ; bub it would leave the Whites and Blacks 
in contact on so many surfaces that it might still lead to a slow process 
of fusion, and would not secure the permanent separation of the two 
races. The champion of this policy, Maurice Evans, indeed admits that 
it offers no final solution of the race problem in the United States. ' There 
is,' he says,' no final solution possible, and the Negro will remain a problem 
for generations to come.' 

3 (6) The Probable Developments in the United States. — If, therefore, 
of the three constructive policies absorption is rejected as it would make 
the United States a nation of octoroons or decaroons, permanent distinct 
co-citizenship be impossible, and segregation be impracticable, what 
development is possible ? No single measure that could be imposed 
on the country by the Legislature appears to be available, but some 
solution may be reached by a process of drift. It is for the geographer 
to search for the factors that are likely to guide this drift. 

One possible movement in the southern States is for much of the 
agricultural work to pass into the hands of immigrants from southern 
Europe, while the Negroes, through that restlessness which is the weakest 


element in their character, tend to settle in the towns. Stone, a represen- 
tative southerner, remarks that planters must seek more reliable labour than 
that of the Negro, who has already been replaced in tobacco cultivation in 
Kentucky. Booker Washington repeatedly called attention to the serious- 
ness of the danger that the Negro would be driven from the skilled occupa- 
tions. The recent agreement between Italy and Mexico for the settlement 
of 500,000 Italians in Mexico would provide an additional source for Italian 
inflow into the southern States. The feeling against inter-racial marriage 
is not so strong among the people of southern Europe as it is with the 
Teutons ; hence extensive south-European immigration into the cotton dis- 
tricts may lead to their future occupation by a hybrid race similar to that of 
tropical South America. This process would render impossible the con- 
tinued refusal of political and municipal rights to any citizen who has a 
trace of Negro blood. The coloured people would regain the suffrage, 
and the political development of the southern States on normal American 
lines would be impossible. If the Whites in the southern States be divided 
between Republicans and Democrats, the Negro vote would hold the balance 
of power ; and owing to the considerable over-representation of the 
southern States in proportion to population, American politics might be 
determined by the Negro vote. Such a situation would be intolerable 
to the northern and western States. Hence, to avoid it, they might agree 
to the south-eastern States being formed into a group with a special 
measure of home rule in some departments of Federal jurisdiction. 

This solution may take a century or more to develop ; but the 
geographical considerations indicate it as the most probable issue from 
the Negro strength in the south-eastern States. 

3 (c) Segregation in South Africa. — The system of inter-racial develop- 
ment by the segregation of the different elements in the population, though 
apparently impracticable in America, is one of the main issues in current 
South African politics.^ 

In Africa, the racial problem, as far as concerns the white and coloured 
races, is simple in most parts of the continent owing to the overwhelming 
majority of the coloured population. In Algeria and Tunis there has been 
an extensive settlement of south-Europeans, with whom the native Berbers 
are racially allied. Most of Africa is the home of Negroes, whose numbers 
are increasing faster than any other population in the world. European 
officials superintend most of the continent, but they and the European 
traders are few in number and are usually temporary sojourners. In a 
few localities, such as the Highlands of Kenya and of Nyasaland, the 
European colonies may be permanent ; but even in these localities the bulk 
of the labour is supplied by Negroes, and much of the retail trade is con- 
ducted by Asiatics. The European colonists are a small dominant 

It is only in the Union of South Africa that the Whites are in sufficient 
numbers to form a considerable proportion in the population ; but their 
future position, even in South Africa, is uncertain. There is no doubt 
of the suitabihty of the South African climate for Europeans. It has been 
the home of a large colony for more than a century, and the white 

1 The general election in South Africa, June 1924, shows the growing strength of 
the movement in favour of segregation. 


Afrikander population is robust and efficient. But the maintenance of 
the white supremacy and even of a white Afrikander people is doubtful. 

The population of the Union of South Africa in 1922 included 1,550,578 
Whites and 5,504,580 coloured people ; so the latter exceed the white by 
3^ to 1 and are increasing the faster. The coloured race is in especial 
excess in Natal, where Indian coolies supply the bulk of the labour in 
agriculture, industry, and retail trade. In the rest of the Union the coloured 
excess is that of the Negro. The white dominion may be maintained either 
by a small oligarchy managing black labour ; or by white workers remaining 
in sufficient number to keep control under a Parliamentary government. 

The oligarchic plan, which is the ideal of the Capitalists, hopes for the 
development of South Africa on the lines adopted in India until recent 
years. This system seems, however, to have little more chance of perma- 
nence in South Africa than in India. The measures introduced to strengthen 
it led Booker Washington to condemn the native policy of parts of 
the British Empire as worse than that of the United States. The rule of 
South Africa by a minority of white men is threatened by the uprise of 
an active Negro party which, with the support of the Ethiopian Church, 
demands its full share in the government of the country. This aggressive 
South African party, largely inspired from the United States, is likely to 
increase in numbers and influence. It may be controlled so long as there 
remains in the country a large number of comfortably circumstanced 
white labourers. The fundamental difficulty in South Africa is, however, 
the position of the ' poor Whites ' ; they form a class who are apt to inter- 
breed with the Negroes and increase the percentage of half-castes. Many 
of the poorer white men have been forced to take work which is despised 
by the better class of black labourers ; and the spectre in South Africa is 
the steady replacement of white workers by Negroes and half-castes in 
the skilled occupations. One difference in South Africa between visits 
in 1893 and 1905 which impressed me as most significant was that all the 
farriery, which in the former year had been done by Whites, had passed 
to the Blacks. This process has gone so far that it threatens the existence 
of white labour in South Africa, and the Capitalist attitude to it has led to 
the alliance of the Nationalist and Labour Parties. One of the main issues 
in contemporary South African politics is the segregation of the Negroes 
and Asiatics. The Nationalists accept the conclusion that the white man 
cannot compete on equal terms with the natives and Asiatics in manual 
labour. The wages for white labour varies from 10s. to 30s. a day ; while 
that of a native adult varies from 6s. to 30s. a mouth. The pay of native 
domestic servants is the same, with the addition of food. The white 
man in South Africa cannot live on the same wages as the blacks. As the 
Negro becomes better educated and enters trade after trade, his white 
competitor must withdraw or reduce his standard of living to a level 
which involves ultimate demoralization. Some of the supporters of the 
Capitalist party admit these facts and consider the fusion of the black and 
white races at the Cape inevitable. 

The Nationalists reject this pessimistic conclusion. They recognize 
that it can only be avoided by maintaining the distinction between the two 
races, which are most liable to commingUng among the poorer classes. The 
Nationalist programme therefore includes the policy of segregation, which 
is opposed by the Capitalists, on the ground that it is an anti-Capitalist 


measure and would raise the cost of labour. General Hertzog and his party, 
however, insist that some policy of segregation afiords the only chance of 
maintaining the position of the white man in South Africa. The segregation 
policy in defence of the Whites seems fully justified by its long adoption in 
the interest of the natives. Thus Basutoland and the Transkei Territory in 
the east of Cape Colony are reserved for the natives ; no European can 
settle in them without the express permission of the Governor-General. 
As white labour is excluded from some parts of South Africa in the interest 
of the Negro, it would seem only fair that the Whites should have a 
corresponding advantage elsewhere and especially in districts which were 
practically unoccupied until the Europeans entered them. According 
to one plan of segregation the natives should have a privileged position 
throughout the eastern lowlands of Cape Colony and Natal, and in some 
eastern districts in the Orange Free State and the Transvaal ; some parts 
of this division of the country should be reserved for the coloured races, 
and no white people allowed to acquire land or an interest in land within 
them. In compensation for this restriction certain occupations and some 
areas should be reserved for the Whites in the western parts of Cape Colony, 
of the Orange River Colony, and of the Transvaal. The principle of 
segregation was approved by the Natives Land Act of 1913, but it has 
obvious difficulties. The British residents in South Africa deplore much 
in the Afrikander Nationalist programme ; but its policy of segregation 
appears to advance the only plan by which South Africa can be developed 
as the permanent home of a large population of the European race. 

V. Tropical Colonization and the Future of Australia. 

We have seen therefore that in North America the presence of the Negro 
has introduced problems of inscrutable perplexity ; that in South America 
a mixed race is in firm possession ; that in Africa as a whole the white man 
has no chance as a colonist ; and that in South Africa his future depends 
on some complex measure of segregation. In Asia only in the north and 
north-west has the white man any prospect of permanent dominion. 
In contrast to these restrictions in Australia the fundamental problem is 
the possibility of the occupation of the whole continent by the European 

When the chief inrush of immigrants into Australia occurred after 1850, 
the belief was almost universal that the natural home of the white man 
was in the temperate zones and that the torrid zone must be left to the 
coloured races. That policy was accordingly adopted by Australia and 
pursued for 50 years. The tropical districts were left open, with varying 
limitations, to Asiatic immigration. Few Asiatics, however, took advantage 
of this opportunity, though large numbers were eager to enter the cities and 
settlements in the south, where the European had done the pioneer work. 
In the north the Asiatics were a hindrance, as they were too few to help 
materially, and they were sufficient to discourage the entrance of white 

In 1901 Australia, on Federation, found itself faced by two problems — 
the empty north which the open-to-Asia policy had not filled, and the 
disturbing effect of indentured coolies on white labour. The poUcy of 
excluding coloured people and working the northern plantations with white 

E.— GEOG R APH Y. 137 

labour was declared to be a physical and physiological impossibility. 
According to Mr. Benjamin Kidd ('Control of the Tropics,* 1898, p. 48), 
' the atten\pt to acclimatize the white man in the Tropics must be recog- 
nized to be a blunder of the first magnitude. All experiments based 
upon the idea are mere idle and empty enterprises foredoomed to failure.' 
Lord Olivier's opinion is that ' Tropical countries arc not suited for settle- 
ment by Whites. Europeans cannot labour and bring uj) families there.' 
Mr. R. \V. Hornabrook declares that to send Whites from Europe to 
Tropical Australia ' is nothing short of a crime — it is worse, it will be 

In 1907, in opposition to this traditional view, I remarked ('Australasia,' 
I., p. 15) that ' medical authorities on tropical climates seem now, however, 
to be coming to the opinion that this view is a popular prejudice which 
does not rest on an adequate foundation.' The evidence to that effect had 
been stated in a remarkable paper by Dr. L. W. Sambon, and endorsed by 
the late Sir Patrick Manson,and has been supported by the general trend of 
medical opinion during the i)ast seventeen years. Thus a leading article in 
the 'Journal of Tropical Medicine' (15 January, 1919, pp. 15-16) proclaims 
' Disease, not climate, the Enemy ... If there is one thing which the study 
of tropical diseases has shown us, it is that disease, and not the climate, 
is the cause of this crippling of trade, of the necessity for frequent changes 
"home," involving expense and the employment of a large permanent 
staflE to fill the gaps caused by sickness, and therefore lessening of profits. 
The legends, a " bad climate," an " unhealthy climate," are well-nigh 
expunged from tropical literature. All medical men familiar with the 
Tropics are cognizant of the fact that disease, and, what is more, prevent- 
able disease, is the cause of the bad name associated with any particular 
region of the Tropics.' 

The general distribution of mankind is in such close agreement with 
the rule that the white race has settled in the temperate regions and 
left the tropics to the coloured races, that any policy inconsistent with 
that arrangement nmst be prepared to encounter a strong prepossession 
to the contrary. Nevertheless, that rule is inconsistent with so many facts 
that it is not a safe basis for a national policy. In America, for example, 
the whole continent, except for the Eskimo in the north, was occupied by 
dark coloured Mongolian tribes, in which, according to Flower and 
Lydekker ('Manmials,'1891,p.752),'thecolour of the skin, notwithstanding 
the enormous difference of the climate under which many members of the 
group exist, varies but little.' The most northerly part of Europe is 
occupied by a coloured race, the Lapps. In Africa the darkness of the 
skin does not always vary in accordance with distance from the Equator. 

L — Supposed Unfavourable Factors in Tropical Climate. 

{A) Heat. — The belief in the unsuitability of the tropics for the white 
man rests on several considerations. Most importance is naturally 
attributed to the heat, as that is the essential difference between the 
tropical and other zones. Intense heat is regarded as injurious to people 
not protected by a dark skin. That view overlooks the automatic process 
by which the living body adjusts itself to temperatures even higher than 
occur in any climate on earth, and that would quickly cook it, if dead. 


During some experiments by Sir Charles Blagden in 1774, Sir Joseph 
Banks remained in a room for seven minutes at a temperature of 211° ; 
and Blagden subsequently stayed at the temperature of 260°, while eggs 
were roasted hard and beefsteaks cooked in a few minutes. White men 
work in furnaces and bakeries at 600° F., and if they can survive such 
temperatures even for short speUs, they should be able to withstand the 
hottest climate on earth. 

That heat is not the dangerous factor in the tropics is obvious from the 
well-known fact that the hottest areas are often the healthiest. Agra is 
hotter and healthier than Bombay, and the summer heat of Colorado is 
fiercer than that in the less healthy Mississippi Valley. 

(6) Moist Heat. — As dry heat affords no explanation of the high 
mortality of some tropical localities, appeal was made to moist heat, and 
to the combination of heat and moisture marked by a high wet bulb 
temperature. At any temperature above blood heat the body is cooled 
only by the evaporation of perspiration, which does not take place in air 
saturated with moisture. Hence in the Townsville experiments ('Proc. 
R. Soc.,' B.xci, 1920, p. 121), a man placed in a room in which the wet 
bulb temperature rose from 98° to 102°, fainted in forty minutes. In a 
hot locality a dose of atropin, which suppresses perspiration, may be 
quickly fatal. 

A wet bulb temperature higher than blood heat would be fatal to men, 
white or black ; but no earthly climate has such temperatures. It was at 
first suggested that the limit of human activity was the wet bulb tem- 
perature of 73°. I have previously quoted ^ well authenticated records 
of miners working for four-hour spells for months at the wet bulb 
temperature of 80° to 90° in Hongkong, the Straits Settlements, Beaufort 
in Borneo, and Ocean Island in the Pacific. At all these places people, 
both white and coloured, survive these conditions. Hence the limit has 
been gradually raised and it is recognized that men can withstand wet 
bulb temperatures of 85°, though the power of work under such conditions 
is necessarily greatly reduced. The highest wet bulb temperature 
mentioned in Dr. Griffith Taylor's record at Port Darwin is 81°. The wet 
bulb data for North Australia are scanty ; but there seems no reason to 
expect that any considerable areas have a more uncomfortable climate 
than Calcutta, to which Dr. Taylor compares the worst localities of 
tropical Australia. Calcutta is one of the healthiest cities in India, and 
has a large and vigorous European population, many of whom spend there 
the whole year. 

Moist heat is trying and must be considered in judging climates from 
the standard of comfort and personal efficiency. The investigation of 
wet bulb temperatures — the significance of which was shown by Dr. J. S. 
Haldane, has been developed in reference to the textile industries by Dr. 
Leonard Hill and Dr. Boycott, to mining by Sir John Cadman, and to the 
conditions of tropical Australia by the work of Professor Osborne and has 
been illustrated by the ingenious climographs of Dr. Gr. Taylor — has 
yielded results of high practical value. But the wet bulb isotherm does 
not delimit the areas where the white man may live and work, and does not 

2 ' The Wet Bulb Thermometer and Tropical Colonization.' Joum. Scott. Meteor. 
Soc, ser. 3, vol. xvi, 1912, pp. 3-9. 


really affect the question of white versus black colonization, as there does 
not seem to be any reason to believe that black men could withstand a 
higher wet bulb temperature than white men. In answer to an inquiry 
on this question, Dr. J. S. Haldane replied that his impression on the 
contrary was that ' white men can usually stand more heat than black 
men,' and he reported the information given him that in places like the 
Red Sea the Clyde stokers stand the heat better than the Lascars, ' and, 
in fact, have constantly to carry the latter out and lay them on deck to 
cool.' Dr. C. J. Martin also informs me that there seems no physiological 
reason why the conditions indicated by a high wet bulb temperature 
should be more adverse to the white man than to the coloured races. 

(c) Monotony in Temperature. — Another temperature factor that has 
been appealed to is that depressing equability of temperature which occurs 
on some tropical coasts. Excessive monotony in the weather is no doubt 
depressing and temperature changes have a stimulating beneficial 
effect. Extremes of cold and heat are still more inconvenient and trying, 
and a moderate equability is often advertised as an attractive feature in a 
climate. The equability of the oceanic cHmate is recognized as most 
favourable for many conditions of health. The areas over which extreme 
uniformity of temperature prevails throughout the year are, however, so 
restricted that this factor does not affect the problem of tropical settlement 
as a whole. With the exception of low tropical islands, places with 
monotonously equable climates are in positions whence a change may be 
secured by a visit to some neighbouring hill country. 

(d) Actinic Rays. — A fourth factor to which much importance has been 
attached in connection with the tropical climate is the effect of the 
chemical rays of the sun. Great importance was once attached to the 
pernicious influence of the ultra-violet chemical rays of the sun on persons 
not protected by a dark skin. Residents in the tropics were therefore 
advised to line their clothes with orange-coloured fabrics to shield them- 
selves from the chemically active rays. These views reached their extreme 
in the writings of Surgeon-Major C. E. Woodruff in 1905 on the ' Effects 
of Tropical Light on White Men.' Woodruff held that the actinic rays of 
the sun are so inimical to the white man that they inhibit his permanent 
settlement within 45° of the Equator. He therefore regarded the tip of 
Patagonia as the only area in the Southern Hemisphere fit for white 
occupation. The temporary stagnancy of the population of Australia 
after the droughts of 1900-1902 he regarded as evidence that the native- 
born white Australian and delicate New Zealander were wasting away 
through physical decay due to the enfeebling sunshine, just as the health 
of American and European children was being ruined by the ' daft ' 
practice, as he called it, of flooding schoolrooms and nurseries with streams 
of light. Woodruff's conclusions have naturally been disregarded. 

Any deleterious effects of the chemical rays of the sun may be avoided 
by the use of appropriate clothes, and physical considerations suggest 
that a black skin should afford less protection than a white skin. Any 
injury that may be wrought by powerful sunshine, according to Aron's 
work in the Philippines, is due to the heat rays at the red end of the 
spectrum and not to the chemical rays. The modern lauded system of 
heliotherapy is based on the belief that strong sunshine is a powerful 
curative agency. 


(e) Miscellaneous Factors. — The four previously considered factors 
have the advantage that they can be readily understood and tested ; but 
as they have failed to provide any basis for the unsuitability of the tropics 
for the white man, the appeal has been shifted to a complex of tropical 
influences, including a rise of body temperature, the lessened activity of 
lung and kidney, and nervous disturbances. Dirt and disease and care- 
lessly prepared food are also mentioned, though they are due to human 
agencies. The physiological effects of the tropical climate in this indict- 
ment are contradicted by high authorities. The rise in body tempera- 
ture is emphatically denied amongst others by Breinl and Young from 
observations in Queensland, and by Chamberlain on the basis of extensive 
observations on American soldiers in the Philippines. A slight rise may 
occur in passing from the temperate regions to the tropics, but it is soon 
recovered ; and Shaklee reports from his experiments on monkeys at 
Manila that ' the healthy white men may be readily acclimatized to the 
conditions named — that is, to the tropical climate at its worst.' Shaklee 
adds that the most important factor in acclimatization is diet. 

The asserted ill-effects of the tropics on respiration appear to have no 
more solid basis. Professor Osborne found at Melbourne that the rate 
of respiration was increased on the hottest days, and his observations agree 
with those of Chamberlain in Manila. So far from the tropical conditions 
being injurious to the kidneys, it is asserted, as by Dr. A. B. Balfour, that 
there is less trouble with that organ in tropical than in temperate climates. 
The apparently inconsistent observations on the action of the kidneys 
between various tropical localities and people, may be explained by 
differences in diet. 

The remaining charges against the tropical climate are insignificant, or 
not based on climatic elements, or are indefinite. Some of the alleged 
factors are trivial, such as the liability to various skin diseases owing to 
a change in the skin reaction ; for if the white man allows himself to be 
kept out of any country by such a cause he does not deserve to get in. 
The hygienic troubles due to association with an insanitary people are 
sometimes adduced ; but they are not an element in climate and would 
not operate in a land reserved for white people. The remaining factors 
rest on ill-defined nervous ailments which are more likely to be due to 
domestic difficulties than to climate. These nervous troubles fall mainly 
on the women who have the strain of disciplining native servants into 
conformity with British ways. Nervous disorders are said to be worst 
in hot, dry, dusty regions which in the tropics are generally regarded as 
the most healthy, except to those whose constitutions require a moist 

2. — Medical Opinion. 

Medical opinion has gone far towards the general adoption of the 
conclusion that there is nothing in climate to prohibit the white man from 
settling in the tropics. 

As an example of a recent authoritative verdict may be quoted the 
report of a sub-committee appointed in 1914 by the Australian Medical 
Congress to investigate the medical aspects of tropical settlement. After 
extensive inquiries, the comparison of the blood of children born and bred 
in the tropics with those of the temperate regions, and other evidence, the 

k E.— GEOGRAPHY. 141 

sub-committee reported in 1920 as follows : ' After mature consideration 
of these and other sources of information embodying the results of long 
and varied professional experience and observation in the Australian 
Tropics, the sub-committee is unable to find anything pointing to the exis- 
tence of inherent or insuperable obstacles in the way of the permanent 
occupation of Tropical Australia by a healthy indigenous white race. 
They consider that the whole question of successful development and settle- 
ment of Tropical Australia by white races is fundamentally a question 
of applied public health in the modern sense . . . They consider that the 
absence of semi-civilized coloured peoples in Northern Australia simplifies 
the problem very greatly.' 

3. — Improvements by Public Sanitation. 

The trend of medical opinion to the view that there is no physiological 
reason why the white race should not inhabit the tropics may lead to a 
change similar to that regarding some localities in the temperate zones, 
which were formerly regarded as death-traps and are now popular health 
resorts. The island of Walcheren, on the coast of one of the most densely 
peopled countries in Europe and only thirty miles from so fashionable a 
watering-place as Ostend, had a century and a quarter ago one of the most ' 
deadly climates in Europe. The largest army which had ever left the 
British islands landed there in 1809. Napoleon did not think it worth 
powder and shot. ' Only keep them in check,' was his order, ' and the 
bad air and fevers peculiar to the country will soon destroy the army.' 
Napoleon's judgment was justified. The force of 70,000 men disembarked 
on July 31 and August 1. By October 10, according to Sir Ranald 
Martin, 142 per thousand were dead of disease, and 587 per thousand 
were ill. 

Algeria is now a trusted sanatorium. Yet disease annually swept away 
7 per cent, of the French army that conquered it. Sir A. M. TuUoch 
remarked that if the French Government had realized the significance of 
that mortality ' it would never have entered on the wild speculation of 
cultivating the soil of Africa by Europeans, nor have wasted a hundred 
millions sterling with no other result than the loss of 100,000 men, who have 
fallen victims to the climate of that country.' The same change of view 
has taken place in reference to some tropical localities. The deadliness 
of the Spanish Main to our armies was described by Samuel Johnson. 
' The attack on Cartagena,' he said, ' is yet remembered, where the Spaniards 
from the ramparts saw their invaders destroyed by the hostility of the 
elements ; poisoned by the air, and crippled by the dews ; where every 
hour swept away battalions ; and in the three days that passed between 
the descent and re-embarkation half an army perished. In the last 
war the Havanna was taken, at what expense is too well remembered. 
May my country be never cursed with such another conquest.' Yet 
Havanna, under American administration, has become one of the healthiest 
cities in the world. 

Sir John Moore, when Governor of St. Lucia (1796), wrote home that 
it is not the climate that kills, but mismanagement. His insight has been 
demonstrated in the same region. The French attempt to build the 
Panama Canal was defeated by disease. Discovery of its nature enabled 


the late Surgeon-General Gorgas to secure for the 10,000 men, women and 
children in the canal construction camps, in spite of the high humid heat, 
as good health as they would have had in the United States. Gorgas 
claimed that the results at Panama ' will be generally received as a demon- 
stration that the white man can live and thrive in the tropics.' Gorgas 
realized that the results for the future are even more momentous. He 
predicted that as ' the amount of wealth which can be produced in the 
tropics for a given amount of labour is so much larger than that which can 
be produced in the temperate zone by the same amount of labour, that the 
attraction for the white man to emigrate to the tropics will be very great 
when it is appreciated that he can be made safe as to his health conditions 
at small expense. When the great valleys of the Amazon and of the Congo 
are occupied by a white population more food will be produced in these 
regions than is now produced in all the rest of the inhabited world.' 

4. — Old-established European Settlements in the Tropics. 

Similar improvements are in progress elsewhere and explain why some 
white colonies have existed for long periods in the tropics without physical 

Two distinguished authorities on Equatorial South America — A. Russel 
Wallace and Richard Spruce — agree that under the Equator in Ecuador 
and northern Peru there are many Spaniards whose ancestors have lived 
there for centuries. Spruce says that some of the Spanish families at 
Guayaquil (lat. 2^13'S.) are pure in race, and have maintained their physical 
fitness after centuries of residence under the Equator. In the West Indies 
there are various old-established European colonies. The island of Saba 
(17°38'N.) was occupied by the Dutch in 1644. The descendants of the 
original settlers still occupy it and, apart from some effects of in-breeding, 
are reported to be healthy and vigorous and incontestably pure in race. 
Some of the German colonies in Brazil are within the tropics, and though 
established as early as 1847 the settlers are in good physical condition ; 
at Santa Katharina, in a low-lying part of the coast just south of the tropics, 
the 85,000 Germans are reported to have better health than the natives. 

The European settlement in the tropics in the small island of Kissa, ofE 
Timor, is especially remarkable for its long survival, despite its small 
numbers and unfavourable circumstances. Eight Dutch soldiers and 
their wives were landed on Kissa in 1665 to hold it against the Portuguese. 
They were forgotten, but they established themselves, and their descendants 
now number over 300. The Admiralty Pilot describes the island as 
unhealthy and feverish. Nevertheless, the Dutch colony is said to be 
healthy, and many of its members have fair hair, blue eyes and blonde 
complexions. They retain the names of the original settlers, but they 
have lost their Dutch language and religion, and have adopted many 
native ways of life. A Dutch missionary, Rinnooij, has referred to the 
settlers as mestizos, i.e. half-castes, and states that the soldiers took 
wives from the daughters of the land. His statements are quite incon- 
sistent with the later and more detailed account by Professor Macmillan 
Brown. If the women of the colony had always been natives of Kissa, 
the survival of the light hair, eye, and skin appears inexplicable. Hence, 
though Macmillan Brown may have underrated the Malay infusion, it 


appears probable that this colony is mainly of Dutch stock, and has kept 
its physical characteristics undamaged by the two-and-a-half centuries of 
residence only eight degrees from the Equator. 

Many cases of the decadence or extinction of ill-placed European 
colonies in the tropics are of course known, such as the Bahamas, as 
described by Professor Ellsworth Huntington. Such misfortunes have been 
regarded as evidence of the inevitably injurious effect of the tropical 
climate on white men. But if white colonies have maintained good 
health in the tropics, the failures are not caused by climate alone. 

5. — The Development of Tropical Australia. 

The experience of colonization in tropical Australia is limited to about 
seventy years ; but it afiords no ground for the expectation that the 
ultimate efiects on the white race will be detrimental. 

(a) Vital Statistics in Queensland. — In Queensland, most of which is 
tropical, the death-rate is lower than in any European country and is 
lower than in most of extra-tropical Australia. In the six years 1915-21, 
according to the statistics in the Australian Year-book (No. 15, 1922, p. 99), 
the crude death-rate in Queensland was the lowest in the six Australian 
States for one year, and fourth of the six States in three years, and the 
fifth in three ; it was not once the highest. In the same six years the in- 
fantile death-rate was lowest in Queensland in three years, and the second 
lowest in two others. According to the same authority, by Index of 
Mortality {i.e. the death-rate in proportion to the ages of the community), 
Queensland was in 1921 the second State in order of merit, being inferior 
only by 03 to New South Wales, the State most favoured in this respect. 

The physical vigour of the Queenslander is shown by his athletic 
prowess, and by the low rejection-rate of recruits from that State for the 
Citizen Army. The longevity in Queensland may be judged by the 
experience of the life assurance offices. It has often been asserted that 
assurance rates show that tropical climates are unhealthy. Yet the chief 
actuary for the greatest Australian assurance company, the Australian 
Mutual Provident Society, reported to the Committee of the Australian 
Medical Congress, ' I have no hesitation in saying that as far as we know 
at present there is no need for life assurance offices to treat proponents 
who live in North Queensland differently from proponents who live in 
other parts of Australia.' 

Physical and mental degeneration in a people living under unfavourable 
conditions would probably be most readily observed in the children. To 
use this clue I asked the Queensland Education Department whether its 
inspectors had noticed any unfavourable symptoms among the children 
in the most tropical of its northern schools. The Department replied 
that on the contrary its schools at Cairns and Cooktown, two of the most 
northern towns, are exceptionally efficient and one of them is sometimes 
the leading school in the State. 

(b) Northern Territory. — The great success of Queensland, although 
more than half the State is within the tropics, renders the more striking 
the failure of the adjacent Northern Territory of Australia, of which the 
records are disappointing. Agriculture has declined ; the Government 
demonstration farms have been reduced to native reserves ; the meat 


works have been closed ; the population has fallen in numbers ; and mining 
production has become insignificant. The present state of the Territory 
has been adduced as evidence of the futility of trying to develop a tropical 
land by white labour. Its failure was not, however, due to the White 
Australia policy, which was introduced after the failure was complete, 
but to geographical disadvantages not yet surmounted. The Territory, 
before 1901, was open to Asiatic immigration, but the hope that it would 
be adequately peopled from Asia was not fulfilled. Its population was 
largest in 1888, and then it was only 7,533. The Chinese were most 
numerous during the construction of the Pine Creek Railway in 1887-8 ; 
their numbers were 4,141 in 1890, and fell to 2,928 in 1900, and to 1,387 
in 1910. High expectations had been formed of the Northern Territory 
from its tropical position, and it was hoped to become an Eldorado as an 
Australian Java. It was fondly called ' the Land of the Dawning,' and 
described as containing limitless areas of, for some piirposes, the best land 
in the world. Searcy, for example, declared that it includes ' land equal 
in size to the islands of Java and Madura, suitable for any sort of tropical 

Careful comparison with Java would, however, have served as a 
warning that easy prosperity was impossible. Java has been a densely- 
peopled, highly-cultivated island, with an advanced indigenous civilization 
since prehistoric times. The Northern Territory of Australia has been 
throughout the same period practically an unoccupied deserted waste. 
Java has rich widespread soils and a convenient rainfall. The Northern 
Territory has in the main poor soils, and its rain all falls during five, and 
most of it during three months, leaving the land parched and scorched for 
seven months every year. The water from the wells is alkaline and the 
supply too small for extensive irrigation, while land irrigated with it is 
soon rendered sterile. 

Poorness of soil, unsuitable distribution of rainfall, and inaccessibility 
of position explain the backwardness of the Northern Territory. Dr. 
Jensen, the former Government Geologist for the Territory, describes the 
agricultural resources as ' circumscribed,' the rich patches of lowland soil 
being ' so wretchedly small and so few,' while the larger areas are situated 
where they could ' only be successfully cultivated by the installation of 
great irrigation schemes, which are not warranted, while equally good 
areas are available in other States with better climate, facilities, and 
markets. ' Great hopes are based on cotton, despite Dr. Jensen's pessimism 
regarding it. Its profitable cultivation appears dependent upon the 
establishment of a protected cotton manufacture in Au.stralia, which 
would secure a market for the crop at a price that would pay for the high 
cost of picking. 

The remedy for the failure of the Northern Territory lies not in another 
attempt with Asiatics, but in the removal of the isolation of the Territory. 
Two routes for railway connection are available — the completion of the 
Mid-Continental Line to South Australia, or the construction of a line past 
the Gulf of Carpentaria to Queensland. The route to Adelaide appears the 
more promising, as it would connect two areas so different that they would 
be complementary and not competitive ; whereas the railway to Queens- 
land would run through one climatic zone and would connect districts 
which yield the same products. No special advantage would accrue to 


Queensland from opening another tropical area ; whereas a railway to 
Adelaide would connect localities in different climatic belts. While the 
only access to Port Darwin from the capital cities of Australia is by a 
voyage of 3,000 or 4,000 miles remote from either of the main steamer 
routes to Australia, the satisfactory development of the Northern Territory 
will be impossible. 

(c) Queensland and the Sugar Industry. — Queensland in contrast to the 
Northern Territory has made firm progress ; the population has continued 
to increase ; and though at first coloured labour was introduced, the pro- 
portion of the Asiatic population in 1911 was only 147 per cent., and of 
the Polynesian only '29 per cent. 

The numbers of coloured labourers in Queensland were too small 
seriously to affect the population, but they were sufficient to be a constant 
irritant and source of uncertainty in the local labour market. This trouble 
led, in 1900, to the prohibition of indentured coolie labour throughout 
Australia. This decision was supported by the great majority of the 
Queensland people in spite of the most emphatic warnings of disaster. 

Some of the sugar estates are in localities with extreme tropical climates ; 
and the Queensland Chambers of Commerce, members of Parliament, 
Farmers' Associations, and bishops, declared that sugar could not be 
grown by white labour. The difficulty was said to be an absolute physical 
impossibility and not merely economic, so that the stoppage of Kanaka 
labour meant the certain death of the Australian sugar industry. At that 
time the sugar plantations were not prosperous, and exclusion of the 
Kanakas was supported on the ground that so struggling and unprofitable 
a branch of agriculture had better die rather than upset the policy of the 
whole continent. 

The Bill for the exclusion of the South Sea islanders was therefore 
enacted and the sugar industry left dependent on white labour. In 
spite, however, of the confident predictions of the experts and their friends 
the industry has gone on and been more successful than when run by 
coloured labour.* The returns of the industry are irregular. In some 
seasons the yield is good, as in the record year 1917-18, and more land is 
planted. An unfavourable planting season reduces the area under cultiva- 
tion and the yields in the second and third years later. Comparisons of 
single years are uncertain ; but the following table shows that the areas 
under cane and the quantity of sugar produced have increased greatly 
since the industry became dependent_on white labour. 

•'' I gave an account of the progress of white labour on the plantations up to 
1908, after a visit to four of the chief sugar-producing districts, in the Nineteenth 
Genturij, February 1910, pp. 368-380 ; and in the Proc. R. Phil. Soc, Glasgow, 
vol. xliii, 1912, pp. 182-194. 




Queensland Sugar Production. 



Cane, Tons 

Sugar, Tons 

































[The sugar yield for 1922 is reported as 288,000 tons.] 

It may be said that the increase in output and area ought to have been 
larger, but it should be understood that the Queensland sugar industry 
is not situated under specially favourable natural circumstances, as the 
land suitable for sugar occurs in relatively small isolated areas. Hence, 
the cane has to be treated at forty scattered mills, and the work cannot 
be done as economically as if concentrated in a few places. 

The Australian adoption of white labour for its sugar plantations has 
been the greatest contribution yet made to the practical solution of the 
problem whether the white man can do agricultural work in the tropics. 
The experiment shows that white labour can be employed successfully 
in such an ultra-tropical industry as sugar cultivation in even the ultra- 
tropical climate of the Queensland coastlands, provided the settlers are 
protected from infectious disease and from the competition of people 
with lower standards of life. 

6. — Rate op Progress and the Drawbacks of the Tropical Climate. 

The results of the Australian decision in 1901 to discard coloured labour 
have shown that the daring policy then begun is practicable ; but it may 
render development slow and costly. The slowness of the progress may be 
amply compensated by its sureness in the end. Some American authorities 
on migration (c/. H. P. Fairchild, ' Immigration,' 1923, pp. 215-225, 342) 
maintain that immigration during the past half-century into America 
has not added to the total population, as it has lowered the birth-rate of the 
older American stock, and merely substituted a very large foreign for a 
native element that would otherwise have come into being. An immediate 
increase caused by the introduction of a large number of Asiatics might 
mean a reduction in the Eiiropean proportion in the Australian race, with 
in the end no increase in the total population. 

The conclusion that white settlement of the tropics is possible should 
not lead to the drawbacks of a tropical climate being overlooked. The 
conditions where the wet-bulb temperatures are high are uncomfortable 
and unfavourable to mental and physical activity. People who are not 
keenly interested in their work should avoid the tropics. Ellsworth 
Huntington in a valuable series of works has called attention to many 
facts which show the dependence of Western civilization on the stimulating 
nature of the temperate climate, for the frequent changes in temperature 
and wind are conducive to alertness and general efficiency. 

The enervating effect of the tropical climate is no doubt counterbalanced 
by various compensations. Man needs less in food, fuel, clothing, and 
housing, while the same amount of exertion will produce a more luxuriant 


and valuable crop. The supremely fertile tropical regions have, however, 
usually a hot muggy climate, which is not attractive to Europeans while 
areas with less trying conditions are available. Northern Australia, even 
if it were not hampered by a high proportion of poor land, would naturally 
develop slowly, just as in Canada the Northern Territory and the rocky 
backwoods have lagged behind the St. Lawrence basin and the rich-soiled 
western plains. 

The natural development of tropical Australia would be by overflow 
from the south when that part of the continent is more adequately peopled. 
Progress could be best aided by opening routes to tempt those with pioneer- 
ing instincts to wander northward. This process may be considered too 
slow by those who consider the immediate occupation of tropical Australia 
a political necessity in order to prevent its annexation by some Asiatic 
Power ; but the alarms based on Asiatic designs against Australia ignore 
the vast empty areas in Asia, the rich lands that could be more easily 
acquired in the Eastern Archipelago, and the persistence with which the 
people of south-eastern Asia have shunned areas in their own continent 
under geographical conditions corresponding to those of most of tropical 

7. — Conclusion. 

The conclusion that the white man is not physiologically disqualified 
from manual labour in the tropics and may colonize any part of Australia 
simplifies inter-racial problems, as it provides an additional outlet and 
spacious home for the European race. 

The preceding survey of the position where the three main races meet 
in intimate association indicates that the world will have a happier and 
brighter future if it can avoid the co-residence in mass of members of 
the different primary divisions of mankind. Individual association and 
contact should secure for each race the benefit of the intellectual, artistic, 
and moral talents of the others ; while industrial co-operation should aid 
each nation to make the best use of the land in its care. 

The world has reached its present position by the help of each of its 
three great races, and it still needs the special qualities of each of them. 
The contemplative Asiatic founded all the chief religions, the ethical basis 
of civilization. The artistic Negro probably gave the world the gift of 
iron, the material basis of civilization. The administrative genius of the 
European race has organized the brain power of the world to its most 
original and constructive efforts. The affectionate, emotional Negro, 
the docile, diligent Asiatic, and the inventive, enterprising European do 
not, however, work at their best when associated in mass. That association 
is attended with serious di£B.culties ; for race amalgamation, which is the 
natural sequel, is abhorrent to many nations, and the intermarriage of* 
widely different breeds, according to many authorities, produces inferior 
offspring. The policy of co-residence with racial integrity has failed to 
secure harmonious progress in North America and South Africa. The 
development of the best qualities of the three races requires their separate 
existence as a whole, with opportunities for individual association and 

In view of the inter-racial diffiowlties that have developed wherever 
the races are intermingled, Australia will throw away a unique opportunity 
if it fails to make a patient effort to secure the whole continent as the home 
of the white race. l 2 






A MAN would be singularly insensible wbo could stand in this place without 
emotion after an absence from Toronto of well-nigh a third of a century ; 
and dead indeed to feeling when, across that long interval, he could look 
back to four years of such experience as fell to me in this City and Dominion 
between 1888 and 1892. The place where a man first makes a settled 
home ; where he first knows the joys and anxieties of family life, where 
he meets with abundant daily kindness in unfamiliar surroundings, can 
never cease to be affectionately remembered. And when it is the place 
where, young and Enghsh as he was, he was entrusted by Canadians with 
the task of organising a new department in a University already important 
and destined to be great, and in a Dominion where he was the first 
Professor of Political Economy, his satisfaction at finding himself un- 
expectedly in the scene of his early endeavours can be readily understood. 
And how much has happened since then ! The material development of 
the Dominion will be the theme of many papers in this and other sections 
of the Association. On the academic side one notes that where there 
were two considerable universities there are now half a dozen or more ; 
that where there was one professorial economist there are now a score. I 
remember with what inward trepidation I confronted my duties. It is 
fortunate that in youth, when one wants it most, one has a better conceit 
of oneself than in maturer years. But this little credit I can take to my- 
self : even in the earliest days of my association with young men and 
women in the University of Toronto, I was never so blind as not to realise 
that here, in Canada, was the future home of a great nationality, with its 
own vigorous patriotism and its own confident outlook on the future. 

Political Economy is now old enough to have reached the stage of 
•retrospect. I shall take advantage of this circumstance, and I shall ask 
you to consider with me a well-rounded body of economic ideas during a 
well-marked period. The body of ideas shall be the general English doctrine 
of International Free Trade. And the period shall be the century approxi- 
mately which followed the publication of the ' Wealth of Nations . ' It is well 
marked in economic literature ; for it covers the time which elapsed before 
the new developments made themselves felt which are associated with the 
names of Jevons and Cliffe Leslie. And it is well marked externally ; for 
it came to an end before England had lost the commercial supremacy due 
to its early utilisation of coal and iron, and before English agriculture had 


begun to be seriously affected by the cheap grain of the new countries. 
The doctrine was imposing by its simplicity and symmetry. It consisted 
of a few easily intelligible propositions, following readily one upon the 
other, and so sweeping in their range, and so optimistic in their impli- 
cations, that they dwarfed all cautious exceptions and qualifications. No 
great English economist indeed — neither Adam Smith, nor Malthus, nor 
Ricardo, nor John Stuart Mill — was, in fact, an out-and-out free trader so 
far as practical application was concerned. Still less were they resolute 
non-interventionists over the whole range of economic life ; for entirely 
consistent and unlimited laissez-faire we should have to go to their more 
severely logical French contemporaries. But they based themselves on 
certain general principles, and they drew from them general conclusions 
which practical politicians could easily employ to justify an absoluteness 
of policy from which they shrank themselves ; they were reverenced as 
spiritual masters, whose occasional aberrations must be lamented or dis- 

I shall endeavour first to set forth the doctrine in a number of brief 
propositions ; then to make some observations under each head. The 
several theses will not be found quite so consecutively stated in any of the 
authoritative writings, and I pursue this method partly for ease of sub- 
sequent reference. But it will be agreed, I expect, that they fairly represent 
the general structure of thought on which rested the whole edifice. 

These, then, are the propositions : 

1. That Nature is beneficent. By ' Nature ' is meant, in this connection, 
the operation of the unpremeditated instincts, desires, passions of 
individual men and women. Any restriction of this operation by an 
authority outside the individual is ' artificial,' and therefore bad. Nature, 
so understood, is the scheme of things created by God. And since God, 
with infinite wisdom, has established this mechanism for the fulfilment of 
His purposes, Nature is, as it were. His Vicegerent, and the ' laws ' of 
its action are ' providential.' But theistic language may be dropped, 
and the theistic conception even repudiated. And then ' Nature ' remains 
as self-directed, and beneficent of itself ; and the reverence with which 
it is regarded amounts in effect to deification. 

This does not mean that every particular action dictated by a ' natural ' 
passion is, considered in itself, morally commendable : it may even be 
' shocking ' to the moral sense. But the ' natural ' impulses work out on 
the whole for good, with only such a minimum amount of evil as is involved 
in the execution of the whole design. The wisdom of God is displayed in 
the folly of men : by an Invisible Hand they are led to promote salutary 
results which are no part of their intention. 

2. That individual Freedom or Liberty is in itself a good thing. This 
is a corollary from, or rather, only another expression for, the preceding 
proposition. For by ' freedom ' or ' liberty ' is meant the right to pursue 
unchecked the instincts or passions implanted by Nature. It is true that 
this liberty must respect the like liberty of others ; and reflection on what 
is involved in this quahfication might suggest some doubt as to the validity 
of the proposition it qualifies. But this line of thought was left for subse- 
quent generations. 

So long as the purpose of the social union is conceived of as the enabling 
of the individual to follow his ' natural ' desires, their pursuit is regarded 


as a ' natural right.' Violations of natural liberty are therefore inherently 
' unjust.' But the conception of inherent individual rights may be repu- 
diated ; and then interference may be condemned simply on the ground 
that it is impolitic from the point of view of social utility. In any case 
the presumption is held to be on the side of ' liberty.' The term, first 
' natural liberty ' and then ' liberty ' or ' freedom ' without the adj ective, 
could thus be used, without formal argument, as bringing with it a 
whole atmosphere of commendation ; while ' interference ' or ' artificial ' 
brought at once, and without attempt at formal proof, a whole atmosphere 
of disapproval. 

3. That society is nothing more than an aggregate collection of indi- 
viduals. Accordingly the wealth, the advantage, the profit of society as a 
whole is but the sum of the wealths, the advantages, the profits of the 
individuals composing it. 

4. That every individual left to himself pursues his own interest his 
own way, and knows it better than anybody else. Accordingly, absence 
of restriction on the individual is the best means of serving the community. 
Social interest is identical with individual interest. 

5. That every country has certain natural advantages. Left to them- 
selves individuals will exert themselves in the directions to which these 
advantages point. It is, therefore, for the benefit of a country or nation 
that they should be left free to do so. 

6. That in each country there is at any moment a certain given 
supply of capital and labour, which cannot be increased by any action of 
the State. Since, left to themselves, they will spontaneously flow into 
the employments most advantageous to themselves and consequently to 
the country, any action of a public authority which directs them towards 
employments to which they would not of themselves go, or keeps them in 
industries which they would otherwise leave, involves loss to the country. 

7. That if another country can supply certain commodities more 
cheaply, it follows that that country must possess advantages which the 
importing country does not enjoy. Since these imports must be paid for 
by exports, they must be paid for by commodities in the production of 
which the importing country has an advantage. Each country thus 
obtains what it wants with the least expenditure of labour or capital, i.e. 
most cheaply, and benefits by international division of labour. Since the 
advantages in question are of divine appointment, to refuse to take the 
fullest advantage of international division of labour is to fly in the face of 
Providence. If the theistic conception is dropped, and the argument is 
based on utility, the offence is the equally serious one of disregarding 
common sense. 

8. That the national capital and labour can be transferred from one 
occupation to another. If an existing industry cannot be profitably 
carried on owing to foreign competition, the capital and labour involved 
can be transferred to some other manufacture within the country, and must 
inevitably be so transferred in order to provide the additional commodities 
necessary to pay for the imports. That the foreign country will — indeed, 
must — take commodities in return for what it sends, proves that in some 
exportable commodities the home country has an advantage. The destruc- 
tion of a native industry is in itself a proof that it has no economic right 
to exist. 


9. That, left to themselves, people will buy whatever they want at 
the cheapest price. This, therefore, must be their interest. And since 
the State is a collection of consumers, and individual interest is social 
interest, the ultimate criterion of the interest of the State is the interest of 

In these nine propositions and their corollaries consists the whole of the 
generally accepted economic doctrine of the century which followed upon 
the great work of Smith. That they were held to be sufficient and decisive 
as late as 1878 is very authoritatively stated in the most widely circulated 
of treatises on the subject — the lectures of Professor Fawcett, which 
appeared in that year and quickly passed through several editions. ' All 
the most effective arguments,' he remarks, ' that can now be urged in 
favour of free trade had . . . been stated with the most admirable 
clearness and force by Adam Smith, Ricardo, and other economists. In 
the pages of these writers are to be found many passages which furnish 
the best reply that can be made to the modern opponents of free trade.' ^ 

1, 2. The first two of the propositions — that Nature is beneficent, and 
that Nature consists in the unrestricted freedom of every individual to 
pursue his personal desires and interest in his own way — were inextricably 
associated in the minds of the first generation of English economists. It 
will be sufficient for our purpose to consider them together, under the term 
Adam Smith himself employs in a famous passage. When all preference 
or restraint, he says, is completely taken away, it gives place to 'the simple 
system of Natural Liberty.' ^ The context shows that by ' system ' Smith 
means both the doctrine and the condition of things which results when 
the doctrine is put into effect. 

We need not spend much time over the genesis of this doctrine. If we 
knew nothing of Adam Smith but the ' Wealth of Nations, 'and took care only 
to read certain parts of it, some sort of case might be made out for the 
view that the doctrine was for Adam Smith an induction from experience : 
this and this and this case of interference with natural liberty, we might 
suppose him to have found, were demonstrably harmful, and therefore, he 
concluded, all interference with natural liberty was harmful. No one need 
deny that some of the instances he cites did lend support to this contention ; 
nor need anyone deny also that the contemporary system of governmental 
or corporate regulation was ill adapted to the needs of the capitalistic era 
then opening. But it would be to disregard all Adam Smith's antecedents 
as a philosopher ; all that we know of the history and transformation of 
the concei^tion of ' Nature ' from the Greek thinkers downward ; all the 
evident affiliation of Smith with his predecessor Hutcheson, and of both 
with Shaftesbury ; and in particular it would be to ignore the essential 
unity of the ' Wealth of Nations ' with Smith's other work, the ' Theory of 
Moral Sentiments,' to refuse to recognise that Smith took over the doctrine 
of Natural Liberty from current theology and moral philosophy. The move- 
ment of his mind was fundamentally deductive : natural liberty, he started 
with believing, is beneficent ; he expected therefore to find all interferences 
with it harmful, and he had no difficulty in discovering instances. 

1 Free Trade and Protection, 6th ed. (188.5), p. 3. 

2 Wealth of Nations, Bk. IV., ch. ix. (ed. Rogers, ii., 272). 


Buckle has asserted that Adam Smith's greatness is shown by his basing 
everything in his Moral Philosophy upon Sympathy and everything in 
his Economics upon Self-interest, and by his leaving his readers to make 
the necessary adjustment between them. It would be a doubtful compli- 
ment, if true ; but no one can suppose it to be true who has read his two 
works attentively. I am not concerned to maintain Smith's philosophical 
consistency ; my own impression, for what it is worth, is that his system 
of moral philosophy is by no means water-tight. But Smith himself, down 
to the end of his life, thought of his Moral Philosophy and his Economics 
as forming one whole. ^ And the recurrence of certain characteristic 
phrases in the second of his books shows clearly enough that he looked 
back on his earlier work as laying his philosophical foundation. 

It is so necessary that this should be realised if we are to judge fairly 
some of his successors, that I will ask you to let me adduce one or two pieces 
of evidence. 

Perhaps the most formal statement of his belief will be found in the 
generalisations to which he is led when considering the social utility of 
' resentment ' — a passion which, he says, is ' commonly regarded ' as 
' odious.' Odious though it be, it is, he holds, useful ; and it is useful, in 
spite of the fact that it is not itself the outcome of conscious reasoning. 
For, as the very existence of society is at stake, ' the Author of Nature has 
not entrusted it to man's reason to find out . . . the proper means of 
attaining this end.' He then proceeds to generalise — substituting a per- 
sonified Nature for her Author. ' The economy of Nature is in this respect 
exactly of a piece with what it is upon many other occasions. With regard 
to all those ends which, upon account of their peculiar importance may be 
regarded, if such an expression is allowable, as the favourite ends of Nature, 
she has constantly not only endowed mankind with an appetite for the end 
which she proposes, but likewise with an appetite for the means by which 
alone the end can be brought about, for their own sakes and independently 
of their tendency to produce it. Thus self-preservation and the propaga- 
tion of the species are the great ends which Nature seems to have proposed 
in the formation of all animals. But ... it has not been entrusted to 
the slow and uncertain determinations of our reason to find out the proper 
means of bringing them about. Nature has directed us to the greater 
part of these by original and immediate instincts. Hunger, thirst, the pas- 
sion which unites the two sexes, the love of pleasure and the dread of pain 
l^rompt us to apply these means for their own sakes, and without any 
consideration of their tendency to those beneficent ends which the great 
Director of Nature intended to produce by them.' You will notice how 
he again falls back into theistic phraseology.* 

Scotch caution abundantly shows itself in both of Smith's books ; and 
the method of hedging implied in the insertion of ' upon many occasions ' 
is highly characteristic.^ But such hedging is never intended to give, 

' Compare the last paragraph of the first edition (1759) of the Moral Sentiments 
with the Advertisement to the sixth edition (1790). 

^ This is in the long note at the end of Moral Sentimeyits, Part II., Sec. I., 
oh. V. (Ward, Lock & Co.'s Reprint, p. 71, under the title Essays ... by Adam 

^ Even this qualification, it will be noticed, disappears with respect to ' all the 
favourite ends of Nature,' where she has ' constantly ' pursued the policy described. 


and does not really give, any serious qualification to the general proposition. 
This is amusingly illustrated by two parallel passages employing an iden- 
tical phrase. In the one he is commenting on the respect which mankind 
has for success, for wealth and greatness. This respect might certainly 
seem to the moralist extravagant ; if not, what Smith himself calls it, 
' the great and universal cause of the corruption of our moral sentiments.' 
He continues, however, unperturbed : ' This great disorder in our moral 
sentiments is by no means without its utility ; and we may on this, as 
well as on many other occasions, admire the wisdom of God even in the 
weakness and folly of man. Our admiration of success is founded upon the 
same principle with our respect for wealth and greatness and is equally 
necessary for establishing the distinction of ranks and the order of society.' * 

In the other passage, Smith is commenting on the fact that ' the world 
judges by the event and not by the design.' This, again, might well seem 
to the moralist unsatisfactory. And so, indeed, it is ; but it is all for a good 
end. ' Nature, when she implanted the seeds of this irregularity in the 
human breast, seems, as upon all other occasions, to have intended the 
happiness and perfection of the species. . . . That necessary rule of justice 
that men in this life are liable to punishment for their actions only . . . 
is founded upon this salutary and useful irregularity concerning merit and 
demerit, which at first sight appears so absurd and unaccountable. But 
every part of Nature, when attentively surveyed, equally demonstrates the 
providential care of its Author, and we may admire the wisdom and goodness 
of God even in the weakness and folly of men.' ' 

The truth is that Smith was bound by his general philosophical position 
to generalise, however frequently Scotch caution might check him for the 
moment. For if ' the happiness of mankind ' was ' the original purpose 
intended by the Author of Nature,' and if Nature was conceived as Smith 
conceived it, then he was prepared to find, on an ' examination of the works 
of Nature,' that they seemed all ' intended to promote happiness and to 
guard against misery.' * Any apparent defects must be the irreducible 
minimum of evil necessary for the existence of the good. 

' All Discord, Harmony not understood ; 
All partial Evil, universal Good,' 

as Pope has it. 

As early as the date of his ' Moral Sentiments ' Smith began to find his 
philosophic optimism confirmed in the economic sphere. ' Success in every 
sort of business ' is ' the reward most proper for encouraging industry, 
prudence, and circumspection. . . . Wealth, and external honours are their 
proper recompense, and the recompense which they seldom fail of acquir- 
ing.' And thus, ' the general rules by which prosperity and adversity are 
commonly distributed . . . appear to be perfectly suited to the situation of 
mankind in this life.' ^ The ' pleasures of wealth,' it is true, are vastly 
exaggerated by the imagination ' but ' it is well that Nature imposes upon 

• The matter is considered at length in two places : Part I., Sec. III., ch. iii. 
(Reprint, p. 56) ; and Part VI., Sec. III. (Reprint, p. 224). 

' Part II., Sec. III., ch. iii. ' Of the Final Cause of this Irregularity of Sentiments.' 
(Reprint, p. 96.) 

« Part III., ch. V. (Reprint, p. 146.) 

» Ibid. p. 147. 


us in this manner. It is this deception which rouses and keeps in continual 
motion the industry of mankind.' ^° 

One more quotation will enable us, by the help of a phrase which re- 
appears in the 'Wealth of Nations,' to pass from the ethical to the economic 
treatise. It is the passage in which he explains how beneficial to society 
in general and the poor in particular are ' the luxury and caprice ' of the 
rich. ' They consume little more than the poor ; and in spite of their 
natural selfishness and rapacity, though they mean only their own 
conveniency, though the sole end which they propose from the labours of 
all the thousands whom they employ be the gratification of their own vain 
and insatiable desires, they divide with the poor the produce of all their 
improvements. They are led by an invisible hand to make nearly the same 
distribution of the necessaries of life which would have been made had 
the earth been divided into equal portions among all its inhabitants ; 
and thus, without intending it, without knowing it, advance the interest 
of the society and afford means to the multiplication of the species. When 
Providence divided the earth among a few lordly masters, it neither forgot 
nor abandoned those who seemed to have been left out in the partition.' ^^ 

You will have been anticipating the passage I now go on to in the 
' Wealth of Nations.' It is that in which he explains how it is that 'every 
individual,' by directing the domestic industry of a country ' in such 
a manner as its produce may be of the greatest value,' though ' he 
intends only his own gain,' ' is in this, as in many other cases, led by an 
invisible hand to promote an end which was no part of his intention.' * 
You observe how the very terms of the former treatise reappear ; not only 
the ' invisible hand,' but also ' intention ' and ' end ' ; and you will realise 
that ' in many other cases ' is not a qualification he intends to be taken 
seriously. The ' invisible hand ' is not, as some have supposed, the chance 
survival of a picturesque literary phrase ; the idea, in that or some equiva- 
lent phrase, is the leit-motif of all his writing. 

However the doctrine grew up in Smith's mind that — as one of my 
predecessors in this Chair has expressed it — ' the natural forces of human 
desires and aversions . . . will naturally, and without conscious intention on 
the part of the individual, lead to the greatest advantage of society,' 
and however much he may have supposed himself to have reached it by 
observation of surrounding facts, there can be no doubt, as that pre- 
decessor of mine has pointed out, that it ' became the starting point' of ' the 
school of propagandists ' who gave Political Economy its English con- 

So much the starting point that it was unconsciously assumed. It hardly 
occurred to most writers explicitly to set it forth ; and here, as elsewhere, 
we can be grateful to McCulloch for proclaiming what others were thinking. 
' The principles on which the production and accumulation of wealth 
depend are inherent in our nature ' . . . and again : ' The principles which 
form the basis of this science make a part of the original constitution 
of man and of the physical world.' " And Buckle, summing up with 

" Part IV., ch. i. (Reprint, p. 162.) 

^^ Ibid. (Reprint, p. 163.) 

* W. ofN., Bk. IV., ch. ii. (II. 28.) 

12 Sir H. Llewellyn Smith, at the Meeting of 1910. 

" Principles (1825), p. 15. (Reprint, p. 16.) 


unbounded admiration more than thirty years later the teachings of Smith, 
declares ' there is a provision in the nature of things by which the 
selfishness of the individual accelerates the progress of the community.' ** 
Where the beneficence of natural liberty is not positively asserted, it is 
of course implied in the use of so condemnatory a term as ' artificial ' to 
designate any limitation of it : as for instance in the Merchants' Petition 
drafted by Tooke in 1820. 

It can be easily understood that when Political Economy passed into 
the hands of a stockbroker like Ricardo and of utilitarian agnostics like 
the two Mills, the language of theism would fall into disuse. No longer 
were they inclined to echo the old saying ' Nature : that is God Himself.' ^^ 
And it was not only because they had ceased to think theologically : it 
was because some at any rate could hardly fail to be more or less 
conscious that the turn Ricardo had given to the doctrine had deprived 
it of its optimistic character, and made it uncomfortably fatalistic. 
' Nature ' was still enthroned ; and if ' God ' means only a Supreme 
Power there was no reason why Nature should not continue to be called 
God, or God's Vicegerent — were it not that the Supreme Power which 
had established ' the Principle of Population ' and ' the natural price 
of labour ' could hardly be respected, let alone loved. 

When, however, we get to the period of the Anti-Corn Law League there 
was a return to Smith's optimism and Smith's theism. ' The responsibility 
of having to find food for the people belongs,' says Cobden in 1846, ' to the 
law of Nature ; as Burke says ' — he continues — ' it belongs to God alone 
to regulate the supply of the food of nations.' ^^ It is congenial to him to 
appeal to ' the will of the Supreme Being ' i' and ' the moral government 
of the world ' ; ^* and to describe Free Trade as ' the International Law of 
the Ahnighty.' ^^ And with the return to a theistic conception went a 
return to the idea of natural rights, which the Benthamite economists 
had likewise thrown over. Thus the petition of the Manchester Chamber 
of Commerce, drawn up by Cobden and two of his friends in 1838, bases 
itself upon ' the unalienable right of every man freely to exchange the results 
of his labour for the productions of other people.' '^^ The eloquent orator, 
W. J. Fox, refused on this ground to compromise on Free Trade : ' It is 
" the very stuff o' the conscience " : it is a principle upon which we have 
made up our minds, as embracing the right of man anterior to the existence 
of civilised society.' ^^ And after the further lapse of a quarter of a 
century, the editor of Bright's and Cobden's ' Speeches,' Thorold Rogers, 
becoming Professor at Oxford and writing ' A Manual for Schools and 
Colleges,' ' assumes,' as of course, ' that there are such rights as are called 
" natural," and that these are the inalienable conditions under which 
individuals take part in social life.' ^^ 

1* Civilisation in England, vol. ii., cli. vi. 

" The mediaeval legist Azo ' explains Ulpian's natura by id est ipse Dens' Pollock, 
Essays, p. 42, from Maitland. 
" Speech of Feb. 27, 1846. 

" Speech of Aug. 25, 1841, quoting a petition of ministers of religion. 
" Speech of Oct. 19, 1843. 

** According to Mallet, Intro, to Political Writings of Cobden, p. vi. 
'" Text in Hirst's collection, Free Trade and the Manchester School (1903), p. 142. 
" Speaking in 1844, Ibid. p. 174. 
^^ Manual, 2nd ed. revised. 1869, p. 223. 


How far tlie retirrn to Adam Smith's type of optimistic theism was 
due to the real religious sentiment of men like Cobden, to their own reading 
of the great Scotch master, and to the contemporary English environment, 
and how much it may have been due to the influence of the contemporary 
French writer Bastiat, it is not easy to say. Sir Louis Mallet, one of the 
literary custodians of Cobden's fame and associated with him in negotiating 
the French Treaty of 1860, regards it as ' one of those coincidences which 
sometimes exercise so powerful an influence on human afiairs ' that, 
while Cobden was leading a political movement in England, ' Frederic 
Bastiat was conceiving and maturing in France the system of political 
philosophy which still remains the best and most complete exposition of 
the views of which Cobden was the great representative.' ' These two men,' 
he affirms, ' were necessary to each other. Without Cobden, Bastiat 
would have lost the powerful stimulant of practical example. . . . Without 
Bastiat, Cobden's policy would not have been elaborated into a 
system.' ^* 

Bastiat has had hard measure dealt to him by later writers. In ex- 
change for the extravagant laudation he received at the time from politi- 
cians and popular writers, he has been treated by recent academic econo- 
mists with a certain patronising contempt. It is allowed that his apologues 
or parables, like the Petition of the Candle Makers against the Sun, are 
amusing reductiones ad absurdum of some of the demands of the Protec- 
tionist man-in-the-street. But he is dismissed as ' a lucid writer, but not 
a profound thinker ' ; and the doctrine ascribed to him — ' that the natural 
organisation of society under the influence of competition is the best not 
only that can be practically effected but even that can be theoretically 
conceived ' — is characterised as ' extravagant.' ^* 

I must avow that I have found nothing in Bastiat's most optimistic 
and theistic passages which is more than a more emotional repetition of 
Smith in the 'Moral Sentiments.' Smith tells us of 'that divineBeing whose 
benevolence and wisdom have from all eternity contrived and conducted 
the immense machine of the universe, so as at all times to produce 
the greatest possible quantity of happiness.' ^^ Bastiat uses the same 
mechanical image : ' The leading idea of this work, the harmony of 
interests, is religious. For it assures us that it is not only the celestial 
but also the social mechanism which reveals the wisdom of God and 
declares His glory.' ^* And the Divine Hand reappears : ' Since in the 
sphere of labour and exchange the principle "each for himself " must 
inevitably prevail as motive power, it is marvellous how the Author of 
things has made use of it to realise in society the fraternal motto " each 
for all." His skilful Hand^' has made an instrument out of an obstacle. 
The general interest has been entrusted to private interest ; and the 
former is inevitable precisely because the latter is indestructible.' ^* 
Before we of this generation are contemptuous of Bastiat, it is only just 

^3 Cobden's Political Writings (1878), Intro., p. vi. 
^* Marshall, Principles, 4th ed., p. 64. 

25 Moral Sentiments, Pt. VI., Sec. II., ch. iii. (Reprint, p. 210.) 
2« Preface To the Youth of France to his Harmonies Economiques (1850). In 
English translation : Harmonies of Political Economy (1860), p. 9. 
" ' Son habile main.' 
2' CEvvres Choisies, ed. Foville, p. 269. 


to look into the rock whence he was hewn, and to the hole of the pit whence 
he was digged. 

The truth is, Bastiat went behind Malthus and Ricardo, back to 
Adam Smith. He pointed out that what distinguished ' the Economist 
school ' of his time from various Socialist schools was at bottom this : 
that the former believed and the latter did not in the necessary harmony 
of unrestricted individual interests. This harmony was the principle from 
which ' the Economist school ' started in their arguments in favour of 
economic freedom. Their practical conclusions were in themselves 
correct ; but the premise, the starting point, could not be correct, Bastiat 
averred — the harmony did not in reality exist — if the Malthusian doctrine 
of Population was true and the consequent Ricardian doctrine of Rent. 
And so, to save the premise, these doctrines must be thrown over.'" 
And that, of course, is just what Cobden did, when he argued so frequently 
and strenuously against the fundamental proposition of Ricardo that the 
price of food regulates the rate of wages. ^"^ 

Is it necessary to say that nowadays no serious thinker believes in 
the two propositions with which I have commenced ? ' Natural ' and 
' artificial ' are words we still use to beg a question ; but no one is any 
longer at all thoroughgoing in their application. ' Nature,' as distinguished, 
as Adam Smith does, from ' the slow and uncertain determinations of our 
reason,' no longer has the comforting sound it once had. We may not 
think of Nature as ' Red in tooth and claw,' or say, with another great 
poet, ' Nature and man can never be fast friends ' ; but we can save 
Nature's character only by including in it precisely what Smith omitted : 
human reason. And when we put aside abstract prepossessions and simply 
watch the operation of social forces, we discover that on neither side of the 
antitheses. Freedom and Control, Liberty and Order, Competition and 
Combination, is there a necessary preponderance of good or evil. Factory 
Laws, Education Laws, Sanitation Laws alike show that no modern 
civilised State any longer believes that social interests can be left to the 

^' It is so easy to miss the precise point in a translation that it will be well to quote 
the original. ' J'ai dit que I'Ecole economiste, partant de la naturelle harmonie des 
interets, concluait a la Liberie. Cependant, je dois en convenir, si les economistes, en 
general, concluent a la Liberte, il n'est malheureusement pas aussi vrai que leurs 
principes etabHssent solidement le point de depart ; I'harmonie des interets.' And 
again : ' La conclusion des economistes est la liberte. Mais, pour que cette conclusion 
obtienne I'assentiment des intelligences et attire k elle les coeurs, il faut qu'elle soit 
solidement fondee sur cette premisse : les interets, abandonnes a eux-memes, 
tendent a des combinaisons harmoniques, a la preponderance progressive du bien 
general. Or, plusieurs d'entre eux, parmi ceux qui font autorite, ont emis des 
propositions qui, de consequence en consequence, conduisent logiquement au mal 
absolu, a I'injustice necessaire, a Tinegalite fatale et progressive, au pauperisme 

'" It is interesting to pass from the first three paragraphs of Ricardo's oh. v. on 
Wages (1817) to Cobden's speeches of Feb. 24, 1842, and Feb. 8, 1844. Cobden 
avowedly bases himself in the matter of wages on Adam Smith ; Speech of July 3, 
1844. {Speeches, 1880, p. 105 ; cf. p. 119.) Compare the attitude toward Malthus and 
Ricardo of Cobden's friend, Thorold Rogers, who, in his Manual, speaks of Bastiat as 
' the great French economist.' But before Bastiat there was at least one notable 
Free-trader who thought it necessary to protest against the Malthusian doctrine of 
Population and the Ricardian doctrine of Rent in order to preserve his exuberantly 
optimistic outlook. This was G. Poulett Scrope, the geologist and M.P., in his 
Principles of Political Economy, 1833. See Preface, p. viii, to edition of 1873. 


unhampered working of immediate individual desires and impulses. It 
is arguable that ' Liberty ' may still be the best policy to pursue in the 
matter of foreign trade. But the contention no longer starts with the 
immense presumption in its favour which it enjoyed so long as it was 
deemed the master key to a divine government of the world. 

3, 4. The individualistic or ' atomistic ' conception of society, or of the 
State as its organised expression, and the doctrine of the identity of 
individual and social interests (in the sense that the pursuit of individual 
interests must necessarily, in general, conduce to social interests) were, 
perhaps, not incAatably associated ideas. For society might be conceived 
of as a mere aggregation of individuals ; and yet, within the society so 
formed, the pursuit of individual interests — since all individuals are not 
equally powerful — might conceivably be regarded as injurious to the 
majority, and, in that sense, to society itself. Some such view was incul- 
cated by Hobbes. From such a conclusion Smith and his followers were 
saved by their underlying confidence in Nature. For if each individual 
retained or should retain in society his natural rights, and if the final 
outcome was bound to be good, that could only be because the pursuit of 
individual rights resulted in the common advantage. It would be super- 
fluous to point out that the individualist view of the essential nature of 
society, and of the State as its organised expression, led to the limitation 
of State functions and to the policy commonl)'- known as laissez-faire. 

As in the case of Natural Liberty we need not ask how the atomistic 
conception of the social union came to Adam Smith. That it characterises 
his school is very certain. But Smith was a man of wide reading, and knew 
too much to readily give himself away by generalities. It is interesting 
to see how his followers forced his ultimate principles into the open. A 
good example is furnished by McCulloch. Time has dealt hardly with 
McCulloch. His name has almost disappeared from modern treatises. 
But he was the man from whom the general British public mainly learnt 
its Political Economy between 1825 and 1850 ; and the republication of 
his first edition in cheap reprints secured currency for his teaching long 
after the middle of the century in certain circles, and that in its earliest 
and least qualified form. Peacock with his ' MacQuedy ' in 1831, and 
Carlyle with his ' McCroudy ' in 1850, knew well enough what they were 
about ; ^^ for McCulloch might reasonably be taken as ' the typical econo- 
mist of the day.' ^^ 

McCulloch has been employed in setting forth the general argument 
for individual enterprise. As is his wont, he does not scruple to appropriate, 
without marks of quotation, choice sentences of Adam Smith — as, less 
frequently, of Kicardo. 

Smith had written thus : ' Every individual is continually exerting 
himself to find out the most advantageous employment for whatever 
capital he can command. It is his own advantage, indeed, and not that 
of the society which he has in view. But the study of his own advantage 
naturally, or rather, necessarily, leads him to prefer that employment which 
is most advantageous to the society.' ^* 

^1 In Peacock's Crotchet Castle and Carlyle's Latter-Day Pamphlets. 
^^ Leslie Stephen, The English Utilitarians, ii., p. 226. 
" W. of N., Bk. IV., ch. ii. (Rogers' ed., ii. 26.) 


Now listen how McCulloch copies this verbatim, but adds ' labour ' 
to ' capital,' and emphasises the completeness of the social benefit. Notice 
still more how he, quite correctly, inserts into the middle of the argument 
the fundamental principle on which it rests : ' It may be observed that 
every individual is constantly exerting himself to find out the most 
advantageous methods of employing his capital and labour. It is true that 
it is his own advantage and not that of the society which he has in view ; 
but, as a society is nothing more than an aggregate collection of individuals,^^ 
it is plain that each in steadily pursuing his own aggrandisement is follow- 
ing that precise line of conduct which is most for the public advantage.' ^* 
The large assumption on which the conclusion depended, viz. that 
individuals know their own interest better than any other man, or 'select 
number of men,' can teach them is, with McCulloch, ' an admitted principle 
in the Science of Morals as well as of Political Economy ' * which hardly 
calls for exposition. 

An individualist view of the social bond involved, as I have already 
observed, a severe limitation of the functions of the State, or, in Adam 
Smith's language, of the ' sovereign.' Herein again Bastiat brings out what 
is implicit in Adam Smith. In his article on the State, written in 1848, 
in the midst of the Socialistic agitation of the period, he prides himself 
on being able thus to characterise it : ' The State is the great fiction by 
means of which everyone tries to live at the expense of everyone ^^. . . 

' To-day as aforetime, everyone would like to profit by the toil of others. 
One doesn't dare to profess such a sentiment ; one conceals it from oneself. 
So what does one do ? We invent an intermediary ; we turn to the State ; 
and one class after another comes and says to it : "You, who can properly 
and honestly do so, take from the public ; and we will share." Alas ! 
the State has only too great an inclination to follow this diabolical counsel ; 
for it is composed of ministers and officials — men, in fact, who, like all other 
men, desire at heart, and seize every opportunity, to increase their own 
riches and influence.' 

For quite such sweeping language from an English pen we have to 
come to America. And here is a characteristic passage from that forcible 
little book by the late Professor Sumner of Yale, ' What Social Classes owe 
to Each Other ' : ^' ' As an abstraction, the State is to me only All-of-us. In 
practice — that is, when it exercises will or adopts a line of action — it is only 
a little group of men chosen in a very haphazard way by the majority of 
us ... " The State," instead of offering resources of wisdom, right reason, 
and pure moral sense beyond what the average of us possess, generally 
offers much less of all these things ' ; and so on. 

In the last half-century we have seen a high doctrine of the State enter- 
ing into England, and in a lesser measure into America, as part of the 
influence of the Hegelian philosophy and of a renewed appreciation of the 

'* McCulloch's own italics. 

'5 Principles of Political Economy (1825), Pt. V., ch. iv. (Reprint, p. 74.) 

* Reprint, p. 16. 

'* ' L'Etat, c'est la grande fiction a travers laquelle tout le monde s'efforce de 
vivre aux depetis de tout le monde ' (Bastiat's own capitals and italics). — CEuvres 
Choisies, ed. Foville, p. 94. There is a poor translation in a volume edited by D. A. 
Wells, Bastiat, Essays in Political Economy (1893). 

»' 1885, p. 9. 


Greek view of the State. We have seen the High-State doctrine confirmed 
by the visible efficacy of much positive State action. We have seen it, 
more recently, somewhat discredited by its association in Germany with 
a deification of the State which has seemed immoral ; and although the 
State in all countries undertook during the Great War, with quite unex- 
pected success, novel functions, its activity has, for the time, undoubtedly 
left behind a certain soreness in some of the business interests afEected. 
Moreover, there has been much analysis in recent years of the conceptions 
Society and State ; much consideration of the place of groups or associations 
within the State, and of a conceivable partition of functions. There are 
schools of political thought who are so indignant with the use which 
Governments calling themselves ' the State ' have made of their powers 
that they propose to abolish the State altogether : although their measures, 
when they seize power, indicate clearly enough that what they believe in is 
something similar under another name. For all these reasons, I naturally 
do not intend to set forth any view of my own, either as to Society or the 
State. I am content to have reminded you of the view entertained by 
the economists of the century we are considering. I do not suppose it 
would satisfy any serious thinker now. He might think Free Trade 
expedient ; but he would not base it upon so one-sided and unhistorical a 
conception of the social union. 

5. The idea that countries differ from one another in their physical pro- 
ductive resources, and that this is the occasion and justification of foreign 
trade, had been a commonplace with writers centuries before Adam Smith. 
It is to be found well developed in the letters of Seneca ; it reappears in 
the great encyclopaedic treatise of Aquinas ; ^* and it was transmitted to 
the modern world by Grotius. ^^ But there can hardly be any doubt that 
it came to Adam Smith from the well-known essays ' Of the Balance of Trade' 
and ' Of the Jealousy of Trade,' published by his friend David Hume in 1752 
and 1758. Hume had written : ' Nature, by giving a diversity of geniuses, 
climates and soils to different nations, has secured their mutual intercourse 
and commerce so long as they all remain industrious and civiUsed.' And 
he had furnished Smith and his successors with a convenient shorter 
expression by remarking : ' When any commodity is denominated the 
staple of a kingdom, it is supposed ' {i.e. understood) ' that this kingdom 
has some peculiar and natural advantages *" for raising the commodity.' 

Hume also led the way for Smith to draw the conclusion that inter- 
ference with the international trade which would arise from the divergency 
in national advantages would be unwise. And it is an illustration of the 

^' This learning is not my own. References will be found in Kautz, GescMchtliche 
Entwiclcelung der Nat. Oek., pp. 156, 215. 

^' Grotiua {De Jure Belli ac Pads, II., 2, 13, 5) quotes from the Greek rhetorician 
Libanius, of the fourth century after Christ, a passage which he translates thus : 
' Deus non omnia omnibus terrae partibus concessit, sed per regiones dona sua distri- 
buit, quo homines alii aliorum indigentes ope societatem colerent. Itaque merca- 
turam excitavit.' 

*" The expression had been used, in 1691, by John Locke, in his Considerations of 
the Lowering of Interest (Reprint in Essays : Ward, Lock & Co., p. 566). He says, of 
Commejrce : ' For this the advantages of our situation, as well as the industry and 
application of our people ... do naturally fit us. By this, . . . trade left almost to 
itself, and assisted only by the natural advantages above mentioned, brought us in 
plenty of riches.' But Locke was far from drawing the Free Trade conclusion. 


hold which the current Nature philosophy had on men's minds that Hume, 
whose own theism was of the most tenuous and hesitating character, puts 
the conclusion in theistic language : ' These numberless bars, obstructions 
and imposts which all nations of Europe . . . have put upon trade . . . 
deprive neighbouring nations of that free communication and exchange 
which the Author of the world has intended by giving them soils, climates 
and geniuses so different from each other.' 

It need hardly be said that this religious interpretation long continued 
to be usual. As the great financier Alexander Baring, later known as Lord 
Ashburton, declared, in presenting the Merchants' Petition to the House of 
Commons in 1820 : ' It is one of the wise dispensations of Providence to 
give to different parts of the world different climates and different advan- 
tages, probably with the great moral purpose of bringing human beings 
together for the mutual relief of their wants.' *^ 

' Natural advantages,' it will be allowed, will commonly be taken to 
mean advantages based on geographical conditions. This is what the 
reader, left to himself, would understand by Ricardo's language, when he 
says that ' a system of perfectly free commerce ' uses most efficaciously 
' the pecuHar powers bestowed by nature ' ; *^ or by Cobden's language, 
thirty years later, when he speaks of England as setting ' the example of 
giving the whole world every advantage of clime and latitude and situa- 

Smith is avowedly taking a strong case when he remarks that ' by means 
of glasses, hot-beds and hot walls very good grapes can be raised in Scotland, 
and very good wine too can be made of them— at about thirty times the 
expense at which they can be imported.' ** But, if this is an extreme 
case, it is something equally clear in essential character, though usually 
less in degree, that the phrase ' natural advantages ' is calculated to imply. 
And this is how Ricardo himself interprets it : 'It is this principle which 
determines that wine shall be made in France and Portugal, that corn shall 
be grown in America and Poland, and that hardware and other goods shall 
be manufactured in England.' *^ 

It will be remembered that Ricardo was writing in 1817 : it was 
then thought that English hardware rested upon natural blessings in the 
way of coal and iron which other nations did not possess. The ' natural 
advantages ' which the United States and Germany, to mention no other 
countries, were destined to find in their coal and iron deposits had not yet 
been discovered. As late as 1832 McCulloch could write in his 'Dictionary 
of Commerce': ' The hardware manufacture is one of the most important 

*i Hansard (N.S.) I., p. 16.5, quoted in Page, Commerce and Industry (1919), I., 55. 

*^ Chap, vii., on Foreign Trade. 

*^ Speech of Feb. 27, 1846. A contemporary variant is ' varieties of climate, 
situation and soil,' in the Edinburgh Review for Jan. 1841 (a reference I owe to the late 
Professor Sidgwick). In Thorold Rogers we find a fresh spring of fervour derived 
from Cobden and Bastiat. The chapter on Foreign Trade in his Manual (1868) thus 
begins : ' The various regions of the earth are variously favourable to the growth of 
vegetable and animal products. Different countries too have different geological 
characteristics.' The exposition of 'special advantages' by the economist who 
replaced Rogers in the Oxford chair is on the same lines : Bonamy Price, Practical 
Political Economy (1878), p. 309. 

" II., p. 31. 

*' Principles, p. 157. 

1924 M 


carried on in Great Britain ; and from the abundance of iron, tin and copper 
ores in this country, and our inexhaustible coal mines, it is one which seems 
to be established on a very secure foundation.' *^ 

' Natural advantages,' however, as a basis for the universal application 
of the policy of free trade, was likely to suggest two comments. One is 
that the greater cheapness with which one country can produce goods 
as compared with another is obviously in some cases due to no peculiar 
advantage in the geographical sense, but simply to the historical fact 
that the manufacture was established there earlier. The other is that 
a country may even possess, geographical advantages for a particular 
production but be unable to develop them if importation is free, because, 
for the time being, another country is producing more cheaply. If the 
' intention ' of ' the Author of the world,' or of ' Nature,' is shown 
by the provision of particular physical resources, it can hardly be sup- 
posed proper to allow it to be indefinitely ' counteracted ' ; *' and this 
vital point in the argument was seized upon by Alexander Hamilton. 
Hamilton, the author of the greater part of ' The Federalist,' is the most 
considerable name in the political science of the United States. His 
famous 'Keport on Manufactures,' written in 1790, only fourteen years 
after the appearance of the 'Wealth of Nations,' and long before List and 
John Stuart Mill, shows a powerful mind working on the material presented 
to him by Adam Smith and the French economists, but with the needs and 
conditions of a new country before his eyes. And as soon as we realise 
that ' advantages ' was a key-word in the discussion, we cannot but appre- 
ciate the dexterity with which Hamilton employs it to justify protection. 
Writing at a time when water was still the usual motive-power for the new 
machinery, he alleges that in that respect ' some superiority of advantages 
may be claimed ' for the United States ; as to the cost of materials, ' the 
advantage upon the whole is at present upon the side of the United States ' ; 
and, generally, ' it is certain that various objects in this country hold out 
advantages which are with difficulty to be equalled elsewhere.' ** 

Adam Smith was quite shrewd enough to foresee criticism on this line. 
He meets it boldly: ' Whether the advantages which one country has 
over another be natural or acquired is in this respect ' {i.e. cheapness) 
' of no consequence. So long as the one country has these advantages and 
the other wants them, it will always be more advantageous to the latter 
rather to buy of the former than to make.' *^ This is of course perfectly 
true, but inconclusive. That one policy is clearly more advantageous in 
the short run does not prove that it must be more advantageous in the 
long run. 

** J. L. Mallet in his Diaries (excerpted in Political Economy Club, Centenary 
Volume, 1921) comments on the success of this Dictionary : ' Two thousand copies of 
the first edition sold, at 21. lOs. a copy, in the course of nine months.' Cobden, in 
1835, described it as ' a work of unrivalled usefulness, which ought to have a place in 
the library of every merchant and reader who feels interested in the commerce of 
the world.' 

*' In the case of the exchange of English cloth for Portuguese wine, ' the intention 
of Nature ' was indicated to McCulIoch by, inter alia, ' the superiority of the wool of 
England, our command of coals,' etc. (Reprint, p. 71.) 

^* In the reprint in Taussig's collection : State Papers and Speeches on the Tariff 
(Cambridge, Mass., 1893), pp. 35, 36, 39, and elsewhere. 

" Bk. IV., oh. ii. (II., p. 31.) 


The form of the long-run idea with which we are most familiar in 
England is the concession which Mill makes, as he says,' on mere principles 
of political economy,' with respect to the possible wisdom of imposing 
protective duties ' in hopes of naturalising a foreign industry in itself 
perfectly suitable to the circumstances of the country,' i.e., as he goes on 
to say, ' where there is no inherent disadvantage.' ^^ This, the so-called 
' Infant Industries ' argument, I need not further elaborate. Mill recog- 
nises that such a policy involves a burden so long as the new industry cannot 
stand without protection ; but ' a protecting duty will sometimes be the 
least inconvenient mode in which the nation can tax itself for the support 
of such an experiment.' It may be remarked that Mill's statement of 
the economic and psychological difficulties under which a new industry, 
in itself perfectly suited to a country, will ordinarily labour, is nothing 
more than what Hamilton had said fifty-eight years before. ^^ Neither 
of them mentions a consideration which modern business has made of 
vast importance : the greater economy of manufacture which large-scale 
production enjoys owing to the wider distribution of overhead charges. 

The form in which the same idea was presented to the German public 
by List was of more philosophical generality. It is summed up in the 
contrast between a policy based on present ' exchange values ' — which is 
his not unjust way of paraphrasing the language of Adam Smith — and a 
policy based on ' productive powers.' By suffering a present loss, a country 
may secure for itself a permanent source of wealth, which may repay, 
many times over, the initial loss. 

I do not propose to enter into the tangled and highly controversial 
question of the extent to which the policy of protecting infant industries 
or developing productive powers has been or can be wisely applied in 
particular countries, at different stages of development, and with varying 
physical resources. I do not forget what is said, and said with a good deal 
of obvious justice, about the selfishness of particular interests, and about 
infants not growing up. It is not necessary to substitute for the belief in the 
necessary beneficence of human selfishness under free trade any belief 
in the necessary beneficence of human selfishness under protection. But 
it is fair, I think, to say that experience, since the time of List and Mill, 
is not altogether barren of what may reasonably be regarded as successful 
applications of the List and Mill principle. As my purpose is merely to 
examine the free trade doctrine of Adam Smith and of the century follow- 
ing as a piece of abstract argument, I will take only one case. 

The tariff history of the United States has long been the happy hunting- 
ground for those who sought evidence of the sordidness of protectionist 
politics. The conjunction of the development of vast physical resources 
with the working, for the first time on a big scale, of practical democracy, 
created conditions not always favourable to political virtue. ' Lobbying ' 
has become a term of such evil sound that to some minds it makes further 
argument unnecessary. 

If, in this sea of dubious issues, any writer can be supposed to steer 
a judicious course, I suppose it is Professor Taussig, the colleague by whose 
side I was proud to serve many years ago at Harvard. In successive 

5» Bk. v., ch. X., p. 1. 

51 See the ' very cogent reasons ' set forth by Hamilton, p. 29, seq. 

M 2 


editions of his book since 1882, he has earned our gratitude by putting 
before us, if not all, at any rate most of, the main facts of United States tariff 
history. Moreover, he has been one of the few writers who have illustrated 
from modern experience the Ricardian doctrine of comparative costs, the 
more subtle form of the general doctrine of natural advantages. And now 
let us listen to what he has had recently to say of the iron industry of the 
United States during the forty years preceding 1915.^2 I a,m anxious not 
to involve him an inch beyond the distance he would be willing to travel. 
I will therefore quote a sufficiently long passage, and will add that, to do 
him complete justice, it should be read in situ. 

' It might be alleged that the iron industry would have advanced 
during the forty years in much the same way, protection or no protection. 
And yet the unbiassed enquirer must hesitate before committing himself 
to such an unqualified statement. Rich natural resources, business skill, 
improvements in transportation, widespread training in appHed science, 
abundant and manageable labour supply — these, perhaps, suffice to account 
for the phenomena. But would these forces have turned in this direction 
so strongly and unerringly but for the shelter from foreign competition ? 
Beyond question, the protective system caused high profits to be reaped 
and the stimulus from great gains promoted the unhesitating investment 
of capital on a large scale. . . . Thereafter, the community began to get 
its dividend. Prices fell. . . . The same sort of growth would doubtless 
have taken place eventually, tariff or no tariff ; but not so soon, or on so 
great a scale. 

' No one can say, with certainty, what would have been ; and the bias 
of the individual observer will have an effect on his estimate of probabilities. 
The free trader . . . will be slow to admit that there are any kernels of truth 
under all this chaff. ... On the other hand, the firm protectionist will find, 
in the history of the iron trade, conclusive proof of brilliant success. And 
very possibly those economists who, being in principle neither protectionists 
nor free traders, seek to be guided only by the outcome in the ascertained 
facts of concrete industry, would render a verdict here not unfavourable 
to the poHcy of fostering " national industry." ' 

The fact that such a verdict is possible in an outstanding case of this 
magnitude is not likely to impede the remarkable inversion of the old 
' natural advantages ' argument which we can see taking place nowadays 
in several directions. There has, of late, been an increase in the number of 
States which have independent control over their fiscal policy. The belief — 
which may or may not be well founded — that these countries are fortunate 
in their climates, or soils, or mineral resources, or water-power, or any 
other of the physical gifts of their geographical situation — and these are 
what the ordinary man means by ' advantages ' — is now suggesting to 
them that, as with any other estate, it may pay them to expend something 
on development. Tariffs or bounties are, of course, from this point of view, 
simply forms of development expenditure. They would be inclined to echo 
the words of Adam Smith, though with a different application : ' What is 
prudence in the conduct of every private family, can scarce be folly in that 
of a great kingdom.' ^* 

5- Some Aspects of the Tariff Question (1915), p. 150. 
S3 Bk. IV., ch. ii. {II., p. 29.) 


An obvious case in point is India, in its new constitutional character. 
In 1922 the Indian Fiscal Commission, after pronouncing for a policy of 
protection ' with discrimination,' recommended the appointment of a 
Tariff Board to exercise that discrimination, and laid down the principles 
by which it was to be guided. And the very first is : ' The industry must be 
one possessing natural advantages, such as an abundant supply of raw 
material, cheap power, a sufficient supply of labour, or a large home market.' 

In this present year the Indian Tariff Board has made its first report 
on a specific industry. It recommends protection for the Indian steel 
industry on these grounds : ' India possesses great natural advantages 
for the manufacture of steel, owing to the richness and abundance of the 
iron-ore deposits and the comparatively short distance which separates 
them from the coal-fields. The natural advantages are so great that even- 
tually steel manufacture in India should be possible at as low a cost as in 
any other country.' Perhaps I had better say that I have no opinion on 
the particular proposal myself. I do not know whether the rich and abun- 
dant iron- ore deposits do in fact exist. But if they do, they are what the 
ordinary man means by ' natural advantages.' 

To the Smithian economist, need I say the only proof that a country 
has an ' advantage ' is the fact that it can produce more cheaply ? ' Advan- 
tage ' with him is a comparative not a positive idea. And yet it carries 
with it an implication that does not necessarily belong to it. In this respect 
it is like the biological conception of the ' fittest ' to survive, or, to come 
nearer home, the economist's employment of " utility.' ' Advantage ' 
suggests that its possession is necessarily a good thing for the country 
which has it. But, in the comparative sense, every country which has a 
foreign trade at all must have an ' advantage ' of some kind or other, or it 
would not be able to export. Anything which enables it to produce 
exports more cheaply than it is worth while for the importing country to 
produce them is an ' advantage.' Read Professor Taussig's books : you 
again and again come on the idea that the reason why the United States 
should not enter upon this or the other branch of production is that the 
commodities in question — e.g. beet sugar — are more cheaply produced 
abroad by docile, unintelligent labour : ' an inferior class which is 
utilised, perhaps exploited, by a superior.' He comes as near contempt 
for them as is possible for a humane man. But if, in the interchange of 
American machinery for European sugar, America's advantage is in its 
high-grade labour, by parity of reasoning the economic advantage of Europe 
is in its low-grade labour. And while this may be a reason for satisfaction 
on America's part, it is not so evidently a reason for satisfaction on Europe's 

And, indeed, as soon as we begin to take a large view of history, it is 
quite certain that the utilisation of comparative advantages has sometimes 
been either a curse or a very mixed blessing. We are all familiar with 
Polish corn as supplying something like a local habitation and a name to 
the argument as to comparative costs. ^* But there is reason to believe 
that the export of corn from the Baltic lands to the countries of Western 
Europe was one of the causes for the depressed position of the peasant of 

" See e.g. James Mill, Elements (1821), pp. 84-88, 135-137 ; followed by J. S. Mill, 
Principles, Bk. III., ch. xvii., § 2. 


the Baltic lands in the 17th and 18th centuries.^* And in the 19th 
century, when the Prussian Junker was a strong free trader in order to get a 
foreign market for his corn, he consolidated the economic ' advantages ' 
of the lands east of the Elbe by buying up peasants' holdings and creating 
an agricultural labourer class which has become the most unsatisfactory 
feature in the German agricultural position.** Similarly, I suppose we 
all feel that the expansion of the American cotton area, and with it of 
slavery — during a period when the Southern planters were ardent free 
traders and anxious that England should be free to buy their raw cotton 
with its manufactures*' — was a means of elevating the coloured race which 
it is difficult to look back upon with equanimity. 

6. The next idea with which we have to deal is that every country 
has a particular supply of capital and labour, and that the State can do 
nothing, by protective measures, bej^ond diverting them to what is pre- 
sumably a less profitable employment. This is stated by Adam Smith, 
first generally : when he says that a monopoly of the home market fre- 
quently turns towards a particular employment ' a greater share of both 
labour and stock of the society than would otherwise have gone to it ' ; and 
then when he makes everything depend on capital, and says that ' no regu- 
lation of commerce can increase the quantity of industry beyond what its 
capital can maintain : it can only divert a part of it.' ** ' Diversion ' is 
the key- word.** 

I will follow Smith's example by concentrating first on capital. And as 
soon as one looks into the exposition as found in Smith or McCulloch or 
John Stuart Mill, it must be apparent that the idea has a close resemblance 
to another once dominant ®" which Mill himself publicly abandoned in 
1869, and which few English-writing economists have since had the temerity 
to say a good word for : the so-called Wage-fund Doctrine. In formulating 
the ' diversion ' argument Smith uses language about wages of which the 
doctrine of the Wage Fund, as defined later, was merely a crystallisation : 
' As the number of workmen that can be kept in employment by any par- 
ticular person must bear a certain proportion to his capital, so the number 
of those that can be continually employed by all the members of a great 

** See the interesting account in Naude, Getreidehandelspolitik, I., 385 (in the series 
Acta Borussica : Denhmdler der Preussischen Staatsverwalhing, 1896). Naude 
attributes the social condition of Poland, the cause of most of its political troubles, 
to the fact that its Government was not allowed by the landlords in the eighteenth 
century to pursue a mercantilist policy. 

** See Memora7idum V. on Germany, by the present writer, in Final Report of the 
Agricultural Tribunal of Investigation (1924), especially §§ 3, 4, 10. 

^' The English reader to whom the connection between slavery and the free trade 
views of the Southern States may be unfamiliar will find some of the relevant facts in 
Dewey, Financial History of the United States (1903), § 80 ; Bogart, Economic History 
of the United States (1907), § 217 ; Coman, Industrial History of the United States 
(1905), p. 190. 

" II., pp. 25-26 ; of. p. 272. Cf. J. S. Mill, Principles, I., v., § 1 ; Rogers, Mamial, 
p. 235. 

^' The phraseology was probably suggested by Hume, who, expounding an idea 
considered below, says, ' If the spirit of industry be preserved, it may easily be 
diverted ' (Essay Of the Jealovsy of Trade). 

*" How dominant we are inclined to forget. But we may be reminded of it by 
reference to the once famous work of Buckle, History of Civilisation (1857), Vol. II., 
ch. vi., p. 357. Buckle speaks of it as ' this vast step in our knowledge. ' 


society must bear a certain proportion to the whole capital of that society, 
and never can exceed that proportion.' *i 

What Mill said about the Wage Fund is equally applicable to ' the 
capital of a society ' in its relation to industry : it is ' not regarded as 
unalterable, for it is augmented by saving and increases with the progress 
of wealth ; but it is reasoned upon as at any given moment a predetermined 
amount.' '^ By a writer like McCulloch, who delights to make things 
superabundantly clear, this is expressly stated : ' No country can possibly 
employ a greater number of workmen than its capital can feed and maintain. 
But it is plain that no restrictive regulation can of itself add one single 
atom to the capital.' " 

The reason, of course, is that given by Adam Smith : ' The industry 
of the society can augment only in proportion as its capital augments, 
and its capital can augment only in proportion to what can be gradually 
saved out of its revenue.' ** 

But all this rests upon a view as to the character and extent of the 
fluidity of capital which was current among the writers of the period we 
are considering but which subsequent experience has shown to require 
profound modification. It was a view which, as we now see, combined 
an exaggerated estimate of the extent to which already invested capital 
is transferable within a country with a quite insufficient estimate of the 
extent to which newly accumulated capital is transferable as between one 
country and another. 

As to the export of capital, Ricardo struck the note in 1817 : 
' Experience shows that the fancied or real insecurity of capital, when not 
under the immediate control of its owner, together with the natural dis- 
inclination which every man has to quit the country of his birth and 
connections, and intrust himself, with all his habits fixed, to a strange 
Government and new laws, check the migration of capital. These 
feelings, which I should be sorry to see weakened, induce most men of 
property to be satisfied with a low rate of profits in their own country, 
rather than seek a more advantageous employment for their wealth in 
foreign nations. '^^ 

All these human touches — ' fixed habits,' and so on — are more appro- 
priate to the age before joint-stock companies than to ours. Ricardo's 
account of the situation is so moderately expressed that it may be defended, 
even for our time, by a charitable interpretation. But the conclusion 
drawn by the succeeding generation was in fact a pretty sweeping one. 
To this clear testimony is borne by that Ricardian of Ricardians, Professor 
Cairnes, writing in 1874 : ' The assumption commonly made in treatises of 
Political Economy is that, as between occupations and localities within 
the same country, the freedom of movement for capital and labour is 
perfect, while, as between nations, capital and labour move with difficulty 
or not at all.' ** 

«i II., p. 26. 

^^ Dissertations and Discussions, IV., p. 42, seq., excerpted in my edition of Mill, 
p. 992. 

" Reprint, p. 73. 

«* Bk. IV., ch. ii. (I. 30.) 

** Principles, ch. vi., p. 161. 

" Some Leading Principles of Political Economy Newly Expounded (1874), p. 302. 


Alexander Hamilton as early as 1790 showed a more statesmanlike 
prevision of the future trend of affairs : ' Notwithstanding there are 
weighty inducements to prefer the employment of capital at home, even 
at less profit . . . yet these inducements are overruled either by a 
deficiency of employment or by a very material difference in profit. . . . 
The aid of foreign capital may safely and with considerable latitude be 
taken into calculation ' *' by a country in the then position of the United 

The history of Foreign Investment and its relation to Production is so 
far an almost untrodden field for the economic enquirer. Some sort of 
impression of the magnitude of the forces set at work may be given by 
the calculation that, before the war, British investments in other lands 
amounted to some 3,500 millions of pounds sterling, almost one-fourth of 
the total wealth of the United Kingdom, ^^ or by the ' common belief in 
the City (of London) prior to the war that the annual savings of the 
United Kingdom were than about 400/. milhons, and were devoted half 
to foreign and half to home investment.' ^* 

No one, I hope, will jump to the conclusion that what I am maintaining 
or even desirous of suggesting is that investment in other countries is 
necessarily injurious to the industry of the country wherein the capital 
has been created. I must not be supposed to be unaware of the contention 
that British investments abroad may help to provide Britain more cheaply 
with food or materials, or in other ways make foreign lands better customers 
for English goods. All I desire to make clear is that the proposition that 
all a Government can do by its legislation is to affect the ai^plication within 
the country of a predetermined quantum of capital is not tenable. It can 
indubitably, in some measure, influence, whether wisely or not, the 
quantum either of home-created or of foreign capital, or of both, devoted 
to production in a particular country. 

In cases where there is no hint of protection by means of tariffs or 
subsidies to suggest alarm, this fact that Government can affect the 
quantity of capital employed is generally recognised. Thus, the 
desirability of encouraging an influx of foreign capital to "England was 
one of the avowed motives of the Patent Act of 1907. Four years later 
it was asserted, apparently on official authority, that ' some fifty firms 
had commenced, or were about to commence, work under the Act, and 
that the new factories involved a total outlay of some 800,000/. It was 
hoped that employment would, in this connection, be found for 7,000 
additional men, and that the wages paid to them would total something 
like 8,000/. per week.' '" It may well be that these estimates were over- 
sanguine ; but it does not seem to have occurred to anyone to deny that 
some attraction of foreign capital to England might reasonably be 
expected to take place, and that, so far as it did occur, it would be loene- 
ficial to England. 

" Report, pp. 38, 39. 

"' This results from a comparison of Sir George Paish's calpulation of ' Great 
Britain's Capital Investments,' in Jour. Roy. Stat. Soc, LXXIV., p. 187 (1911), 
with the Economist's calculation of national wealth in Hirst's chapter added to 
Porter's Progress of the Nations (1912). 

"^ Lavington, The English Capital Market (1921), p. 205. 

'0 Times, March 23, 1911. 


And one may go a step further. That, under certain circumstances, 
a tariff might have the effect of causing foreign manufacturers to set up 
works within the tariff walls has, for some time past, been illustrated by 
numerous and not unimportant examples ; and English manufacturers 
have not been deterred from yielding to the pressure of foreign tariffs and 
establishing works abroad by any personal views of their own as to Free 
Trade or Protection.'^ They have often taken with them a nucleus of 
skilled English workmen. 

But now, in recent years, various Governments have begun once more 
to take notice of the fact that tariffs do, under certain circumstances, 
cause foreign capital to be introduced, and to use it as part of the 
justification of a protective policy. I may give two examples. One can 
get from the Bureau of Commerce and Industry of the Commonwealth of 
Australia a long list of ' some of the British Manufacturers who have 
established interests in Works and Factories in Australia.' Among them 
will be found a dozen or more of the best-known English concerns. And 
the list is headed by the following notes : — 

' (1) New names are being added to this list every week, and it shows 
that in the opinion of some of the most progressive British manufacturers 
it will pay to bring plant and skilled workers to the raw material in 
Australia . . . 

' (2) The new Australian Tariff is calculated to bring about the establish- 
ment of every natural and essential industry ; and as the tariff affords 
real protection and opens up excellent prospects to the efficient, the next 
few years will see considerable industrial progress in Australia.' 

I have no opinion as to the wisdom, in Australian interests, of its 
present tariff. I cite the case simply as showing how impossible it is now 
to speak as if the capital which a country can have for its manufactures 
must always be entirely accumulated within the country itself.'^ 

The other case is even more significant. The new Irish Free State 
appointed last year a Committee of five Irishmen, of whom four were 
economists, to advise it as to its tariff policy. The Committee reported 
in what, with sufficient accuracy, may be called a free trade direction. 
But in that report occurred the following passage : ' The more complete 
the protection afforded by a tariff, the greater will be the inducement to 
outside competitors to retain their Irish market by coming inside the 
fiscal barrier and establishing factories in the Free State. And in the 
existing condition of industry the expenditure will be undertaken by very 
large industries in the hope of retaining even a small fraction of their 
existing market. . . . The new competitor will, it is true, in a sense 
establish an Irish industry and provide employment for Irish workers.' 

All that the Committee find to say, by way of demurrer, is that ' in 
this case backward Irish industries will be faced by a home competition 
from a highly organised rival quite as serious as that from which they 
have sought to escape.' " That is to say, free trade must be maintained 
in the interests of ' backward Irish industries.' 

" Some examples prior to 1903 are collected in my Tariff Problem, p. 77. 

'^ This -was Sir Robert Giffen's line of thought as recently as 1877. In his paper 
on Foreign Competition he argues that ' the amount of capital required to replace us 
even partially is so great that it must take many years /or our competitors to accumulate 
any such amount ' (Economic Inquiries and Studies, II., jj. 429). 

''^Reports of the Fiscal Inqidry Committee, Dublin, 1923, § 126. 


A century and a third before, Alexander Hamilton had thought it 
necessary to refer to a like fear of competition with the home producer : 
' It is not impossible that there may be persons disposed to look with a 
jealous eye on the introduction of foreign capital, as if it were an instru- 
ment to deprive our own citizens of the profits of our own industry.' 
His own view was different : ' Instead of being viewed as a rival, it 
ought to be considered as a most valuable auxiliary ; conducing to put in 
motion a greater quantity of productive labour and a greater portion of 
human enterprise than could exist without it.' '* 

The Government of the Irish Free State seems more inclined to follow 
Hamilton's lead than to be deterred by the prophecy of its Tariff Com- 
mission ; for the Minister in charge of the measure which has lately been 
introduced into the Dail for ' a limited . . . experiment in the use of a 
tariff for the stimulation of Irish industry ' ''^ expressly mentioned the 
expectation of attracting capital from outside as one of the motives 
justifying the new departure. Here, again, I had better safeguard myself : 
as to whether a tariff on the particular commodities proposed is wise for 
Ireland I am not in a position to have an opinion ; nor do I know how 
much non-Irish capital is likely to be attracted in these particular cases. 
I refer to this instance of Ireland simply as showing that not only the 
Irish Government but also its Committee of Economists are of opinion 
that legislation can have some influence on the amount of capital 
employed within the country. 

I shall pass to more controversial ground if I refer to recent events 
in Great Britain itself. But it ought to be possible to state what, as far 
as one can make out, are assured facts without implying necessarily any 
opinion as to the policy with which they are associated. One is that the 
Swiss Cl^mical interests have been encouraged to enlarge considerably 
their plant in England since the Dyestuffs (Import Regulation) Act 
became operative in January 1921. The other is that the McKenna 
Duties have led some of the largest foreign manufacturers of motor-cars 
to establish works in Great Britain. They have usually begun with the 
importation of parts, and with merely assembling and finishing in Great 
Britain ; yet even for that purpose large factories and many workpeople 
are necessary. In one important instance, manufacture has become 
almost entirely British. That the British preference on imports from the 
Dominions has had the effect of causing a certain transfer of American 
capital to this Dominion is, of course, well known to the Canadians in 
my audience.'* 

Perhaps some countries may be the better without imported capital 
and others without exporting it : perhaps the Governmental measures 
which influence the movement in either direction are ill advised, and we 

'* Report on Manufactures, p. 39. 

'^ Dail Eireann : Parliamentary Debates, April 25, 1924, p. 42 (tobacco, boots, 
confectionery) ; 70 (jam), cf. the utterances of other Deputies ; 127 (boots) ; 130 
(tobacco) ; 155 (soap). 

'* As lately as 1887 Lord Farrar will be found arguing that the increase in wages 
paid and persons employed in Canada under its protective policy must have been 
due to ' a compulsory and artificial transfer of the labour and capital of Canadians 
from the industries in which they can produce more, to,' etc. : Fair Trade v. Free 
Trade (4th ed., 1887, p. 63). The investment of foreign capital, especially American, 
in Canada, awaits, I think, its historian. 


may sigh for the uncomplicated simplicity of the time when every country 
used only, and used all of, the capital it had itself accunmlated. But 
that is not the world in which we live. 

7, 8. The next of the generally accepted propositions in the sequence 
we are now considering was this : that while the capital and labour within a 
country were quantities the amount of which no Government action could 
influence, they could readily be transferred from one industry to another 
within a country, if their previous employment were taken from them by 
imports. It is the doctrine of the Internal Transferability of capital and 
labour, as existing conditions rendering free trade always beneficial. 

The history of the literary presentation of the idea is suggestive. Like 
so much else, it probably came to Smith from Hume. Hume, in seeking to 
remove the alarm lest the ' interference ' of our neighbours with any of our 
staple trades could do us great harm, argues that ' if the spirit of industry 
be preserved, it may easily be diverted from one branch to another ; and 
the manufacturers of icool, for instance, be employed in linen, silk, iron, or 
any other commodities for which there appears to be a demand.' ^' 

From this statement Hume would probably not have been disposed 
to draw the sweeping practical conclusions of later writers ; '^ yet here is 
the transferability idea in germ. Of the idea in relation to capital I have 
already said something. Let us fix our attention on labour ; for ' manu- 
facturers ' here means manual operatives. 

Hume was writing in 1758. The use of coke for smelting iron was only 
just beginning ; none of the great inventions in the iron and mining 
industries had yet been introduced : neither puddling, nor rolling, nor the 
steam engine. The only textile industry to which ' power ' had been applied 
was the relatively small silk industry ; not one of the revolutionary changes 
in cotton spinning and weaving had been made, and the engineering and 
shipbuilding trades were far in the future. Moreover, Hume is specifically 
referring to ' the staple industries ' of the country ; and there may have 
been some justification in the pre-machine age for thinking that — except 
in the case of highly skilled artisan crafts producing luxury goods — 
labour could move pretty easily to and fro. Even so, the ' easy ' diversion 
of workpeople from the textile industries to the iron manufacture rather 
suggests a literary man's unacquaintance with the actual conditions of 
working-class life. 

Adam Smith, twenty years later, thought it necessary to argue the 
matter more at length. He makes four points.'* The first is, that the 
soldiers and seamen disbanded at the end of the Seven Years' War were 
gradually absorbed in the great mass of the people and found work in a 
variety of ways, without any ' sensible disorder/ ' though they no doubt 
suffered sotne inconveniency.' ' To turn the direction of industry from one 
sort of labour to another ' ' is surely much easier.' The second is that, 
' to the greater part of manufactures there are other collateral manufactures 
of so similar a nature that a workman can easily transfer his industry from 
one of them to another.' The third is that ' the greater part of such workmen 

" Essay, Of the Jealousy of Trade. (Reprint, p. 197.) 

'* For he continued to print by the side of this Essay the preceding Essay in which 
he argued that ' a Government has great reason to preserve with care its people and 
its manufactures.' 

" Bk. IV., ch. ii. (II., 43) ; italics added. 


are occasionally employed in country labour.' And finally that, whatever 
happens, there will, in any case, remain the same ' stock ' or capital in the 
country, and that this will employ an equal number of people in some 
other way. 

Obvious comments may be made on each of these points. The use of a 
term like ' inconveniency ' ; *" the use of the word ' easily ' to describe 
transference even to ' collateral ' manufactures ; *^ the view that whatever 
particular home industry might be killed by foreign imports, ' the capital 
of the country remains the same '— a view so increasingly difficult to hold, 
as capital comes to be fixed in specialised plant ; these points each 
suggest some evident reflections.*^ But it will be enough to dwell for a 
moment on the remarkable argument that ' the greater part of workmen 
in manufactures are occasionally employed in country labour.' In the age 
of ' domestic industry,' agriculture and manufacture were in truth often 
combined, in various ways, by the same persons or families ; though one 
may doubt whether this was true of 'the greater part of workmen in manu- 
factures' in England at the time Smith was writing. Need one say that the 
whole trend of development ever since has been away from such a combina- 
tion, above all in England ? 

When we come to McCulloch, half a century later, there is an unmistak- 
able change in the intellectual atmosphere. This country had in the 
interval entered, first of all the nations, into the machine and factory age ; 
and, whether it was owing to that cause alone and the consequent cheapness 
of our commodities, or to other causes also, England had for the time a 
monopoly of the most important manufactures. The cotton industry, hardly 
existent in 1776, in 1825 was exporting goods to the value of much over 
18 millions of pounds sterling. We had been, on balance, an iron-importing 
country ; in the last three decades, imports had fallen by three-quarters, 
and exports had quadrupled. Accordingly, McCulloch could write quite 
in the strain of Rule, Britannia ! Other nations might not be so blest, but 
tve should flourish ! Whatever ' loss and inconvenience ' might follow a 
Free Trade policy ' in other countries,' ' our superiority in the arts is so 
very great, that only a very inconsiderable proportion of our population 
would be driven from the employments now exercised by them by the 
freest importation of foreign products.'** 

Accordingly there was no need to alleviate possible apprehension by 
invoking the aid of occasional agricultural employment. Any residue of 

^° The word is echoed by Fawcett, Free Trade and Protection, jj. 9 : ' The loss and 
inconvenience which always accompany the transfer of capital and labour from one 
employment to another.' 

'^ Smith did, at any rate, unlike Hume, limit the ease of transference to ' collateral ' 
manufactures. T. B. Say — who, according to Ricardo, ' succeeded in placing the 
science ' of Smith ' in a more logical and instructive order,' and had more influence on 
English writers than is now remembered — rivals Hume in his economic imagination. 
If, he says, France refuses to take English woollens, ' England will employ the same 
capital and the same manual labour in the preparation of ardent spirits by the 
distillation of grain that were before occupied in the manufacture of woollens for the 
French market.' (1803 ; English translation of 1820.) 

^" Smith on the next page recognises that that part of manufacturing capital 
' which is fixed in workhouses and in the instruments of trade could scarce be disposed 
of without considerable loss.' He could not foresee how large a part this was destined 
to become. 

«3 Part II., Section II. (Reprint, p. 7C.) 


doubt could be expeditiously disposed of by a piece of abstract argument, 
showing that, even in the improbable contingency that ' a few thousand 
workmen ' lost their jobs through free imports, no harm would be done. 
For since imports must be paid for by exports, an amount of work must be 
called for to create them, ' equivalent ' to that dispensed with. And this 
doctrine is asserted in its starkest form. There is no suggestion that the 
gain will be to the men already in those other trades which will now have 
larger exports, so that the nation would not suffer as a whole ; or that the 
labourers now left idle will ultimately get absorbed. No ; nobody is going 
to suffer, even for a short time. ' Suppose that, under a system of free 
trade, we imported a considerable portion of silks and linens now wholly 
manufactured at home. ... It is obvious that such of our artificers as had 
previously been engatjed in our silk and linen manufactures, and were thrown 
out of these employments, could immediately obtain employment in the 
manufacture of the products which must be exported as equivalents for 
the foreign silks and linens.' ** 

It was not for another half-century that an English economist who 
could get the ear of the public began seriously to consider how far the 
transferability of labour and the transferability of capital — which he justly 
described as ' the postulates of ' the then current ' Political Economy ' — 
were in fact true.** Anyone who looks at his Economic Studies ** will 
observe that Bagehot gives much more attention to capital than to labour ; 
and that, as to labour, he occupies most of his space in demonstrating that 
in earlier times and to-day in primitive countries labour is 7iot transferable. 
But, for such a country as England is now, he thinks ' no assumption can 
be better founded.' Labour does not flow so quickly from pursuit to 
pursuit as capital does : ' but still it moves very quickly.' There are, he 
grants, even at present in England, many limitations to mobility. ' There 
is a "friction," but still it is only a " friction " ; its resisting power is mostly 
defeated, and at a first view need not be regarded.' 

Like so much else in actual industrial life the question of the extent of 
the mobility of labour has been subjected to very little quantitative in- 
vestigation. But all who have come into close contact with the industrial 
population of the older countries will agree with me in feeling that ' friction ' 

^* la the edition of 1843 (p. 151) for immediately i.s substituted in future. But it 
is still the discharged artificers themselves who find the equivalent occupation. 

85 Senior, as long before as 1835, had pointed out, with remarkable insight, that 
the mobility of labour was being lessened rather than increased by the industrial 
revolution. ' The difficulty with which labour is transferred from one occupation to 
another is the principal evil of a high state of civilisation. It exists in proportion to the 
division of labour.' As to capital, he anticipated recent writers by pointing out that 
' those costly instruments which form the principal part of fixed capital can scarcely 
ever be applied to any but their original purposes. They are employed, therefore, 
in the same way, long after they have ceased to afford average profit on the expense 
of their construction, because a still greater loss would be incurred by attempting to 
use them in a different manner.' — Political Economy (in the series Encyclopcedia 
Metropolitmia), reprint of 1854, p. 217. 

The disregard by subsequent writers of what one might suppose suggestive observa- 
tions is curious when contrasted with the readiness with which Senior's Abstinence 
view of Interest and his sharpening of the Wage Fund idea were accepted. It was, 
perhaps, due to the failure of Senior to make any large theoretic use of the observations. 
And ideas which can be fitted into a prevalent general body of thought are more likely 
to be assimilated than disturbing ones. 

"6 1880, p. 21, seq. 


is an inadequate and misleading term, and that, in any case, it is very neces- 
sary to go on to a ' second view.' Doubtless there is a considerable slow- 
movement mobility — the mobility of a glacier rather than that of a stream. 
It is chiefly exhibited in the inclination of young people (or their parents) 
away from obviously declining trades and towards such trades as happen 
to be within their reach where employment is supposed to be good. And 
then there are occupations — for instance, that of a carpenter — in which 
men can find employment in two or more alternative 'industries,' in the 
wider sense of that word now coming into use — for instance, in building 
proper or in shipbuilding. But the fact seems also to be that a v/orkman 
with definite acquired skill seldom changes his occupation in a country like 
England ; and I imagine this is the case also in the older countries of 
Europe. Even unskilled men, mere ' labourers,' seldom leave ' the industry ' 
— in the wide sense of the term — with which they have been associated. 
This is the case even when better-paid and more regular work is in fact 
available in some other occupation : the reasons are to be found partly 
in inertia, partly in attachment to local ties, but also quite as much in 
the need, or supposed need, of acquiring new skill, and the difficulty as well 
as risk of doing so. And hence, wljen men become unemployed, they cling 
to their own trade in the hope of being taken on again, to an extent which 
is inconceivable to middle-class people. Still more is this the case when it 
is short time or lowered remuneration they are suffering from. 

Some of the recent developments of industrial organisation and legis- 
lation in the older countries which most of us regard with satisfaction have 
for their effect to lessen mobility. This is the result, for instance, of trade 
unionism, among more or less skilled operatives. The assertion that 
' trade unions increase mobility of labour ' *^ is true as between particular 
shops and particular localities in the same industry : it is the reverse of 
true for adult workpeople who desire to shift from one industry to another. 
To say that certain trade unions do in effect impose obstacles to entry 
upon a trade is not necessarily to condemn them : it is but to state a fact. 
Unemployment insurance again, in a country where there are recognised 
standards of wages, is bound, if it recognises a claim to a certain standard 
on the part of unemployed persons, to strengthen the tendency of work- 
people once in a particular trade to stick to it. The National Insurance 
Act of 1920 lays down that a workman is justified in demanding unemploy- 
ment benefit and declining proft'ered employment if that employment is 
not ' suitable.' If employment is offered in the same district — as will 
often be the case — it can be refused if the rate of wages is lower or the 
conditions less favourable than in the employment in which the workman 
was before ordinarily employed. And there seems to be a natural tendency 
in recent decisions of the courts to allow specially trained or skilled men 
and women to refuse unskilled work, especially if it could be thought to 
endanger their return to skilled employment. 

The effect which unemployment insurance may well have in this respect 
is more than hinted at in the comments of several of the Governments on 
the definition of unemployment recently proposed by a Technical Commis- 
sion appointed by the International Labour Office at Geneva. That defini- 
tion ran as follows : ' Unemployment may be defined as the condition of a 

8'' Beveridge, Unemployment, p. 105, and Index under Trade Unions. 


worker who is both able and willing to work but is unable to find employ- 
ment suitable to his qualifications and reasonable expectations.' The impli- 
cation of such a clause in a European country is indicated in the approving 
comment of the Government of Finland : ' Skill in a trade and the possi- 
bilities of remuneration depending thereon generally fix the reasonable 
expectations of a worker.' On the other hand, the Governmejits of new 
countries like Canada and South Africa are unwilling to recognise the claim 
which seems to be involved in ' reasonable expectations.' The explanation 
is that the industrial conditions are in fact very different. This is well 
explained by the Government of South Africa : ' In the Union, with the 
exception of clearly defined trades . . . workers do not confine themselves 
to specified occupations, as they do in older countries where occupations 
and industries are more sharply defined or firmly established.' *^ 

In a work which is among the most outstanding products of English 
economic inquiry in the present century, and which has had powerful 
influence on English legislation, I find the sentence : ' Adam Smith and 
his followers were right in emphasizing the mobility of labour as the cardinal 
requirements of industry.' ** In the table of contents this appears as : 
' The demand of economists for mobility of labour.' Adam Smith and 
his immediate followers did indeed ' demand ' it, as itself a good thing in 
the interests of production. Later economists have sometimes been more 
cautious and have ' demanded ' it, but only as a postulate of their deductive 
reasonings, without committing themselves to an opinion as to its own 
merits. To assume its merits, without sufiicient regard to contemporary 
conditions, and to base the establishment of a widespread governmental 
organisation upon this one ' demand,' is likely to lead to some disappoint- 
ment with the results — as has been in the case with the British Labour 

When a long-established industry in England has been seriously damaged 
— as has, of course, occurred again and again — by changes in foreign tariffs, 
it has, I think, seldom happened that it has entirely disa2)peared. It 
may permanently contract into narrower dimensions, and in the next 
generation its place in a particular town may be taken by another and newer 
industry. In this case its disappearance will have been attended by an 
amount of suffering and, what is worse, of demoralisation which ' friction ' 
hardly indicates. Or in another ten years it may have obtained new 
markets in other lands, and its output may be as large as ever. In 
this case we shall be told what an admirable thing is freedom in stimulating 
the enterprise of manufacturers and compelling them to improve their 
methods. That it sometimes does both, I do not dream of denying. But 
the deterioration of character which does so easily beset workpeople during 
protracted periods of unemployment or under- employment is at least as 
important a fact as the blessings of the subsequent rebound. 

And there is this to be added that, just as the old doctrine of the national 
capital exaggerated its fluidity within a country when already invested in 
plant, and minimised its fluidity as between countries when newly created, 
so the doctrine of the national labour-force overestimated its transferability 

** Methods of Compiling Statistics of Unemployment. Intern. Labour Office : 
Studies and Reports, Series C. Unemployment No. 7. Geneva, 1922. See pp. 9, 
10, 11, 16. 

*° Beveridge, Unemployment, p. 216. 


from industry to industry within an old country, and overlooked the 
possibility of its transference to the same industry in another country. 
The migration of skilled labour to carry on its old occupation in a protected 
country does not take place on so large a scale as the migration of fresh 
manufacturing capital. But it has taken place repeatedly and is taking 
place now. And whether we in England or any other of the older countries 
view the phenomenon with complacency or concern, it presents a different 
picture to our eyes from that which was present either to Smith or to 

9. The last of the large ideas which characterised the period we are 
considering is the unique emphasis it laid upon cheapness to the consumer 
as the test of social policy. I shall not go beyond Adam Smith for this. 
I will only quote three well-known passages. In the first he says : ' In 
every country it always is and always must be the interest of the great 
body of the people to buy whatever they want of those who sell it cheapest. 
The proposition is so very manifest that it seems ridiculous to take any 
pains to prove it.' ^^ 

In the second, with the same crushing air of certitude : ' Consumption 
is the sole end and purpose of all production ; and the interest of the 
producer ought to be attended to, only so far as it may be necessary for 
promoting that of the consumer. The maxim is so perfectly self-evident, 
that it would be absurd to attempt to prove it.' *^ 

The third passage is a compact summary of the system he founded. 
It is that in which he speaks, as it were in passing, of ' the cheapness of 
consumption and the encouragement given to production ' as ' precisely 
the two objects which it is the great business of political economy to 
promote.' "'^ 

I remember, when I was at Harvard, going, in the company of Francis 
Walker, to dine at the house of Edward Atkinson. None could know 
Atkinson without liking him ; and we had personal reasons that evening 
for being interested in ' the Atkinson Cooker.' But all I remember of the 
economic discussion which followed the repast was Walker's snort of 
speechless protest when Atkinson explained that to buy in the cheapest 
market and sell in the dearest was to carry out the Golden Rule. I 
thought it was only a playful extravagance on Atkinson's part, but original. 
I had not read my Cobden then as I have since had occasion to do. I did 
not know that the identification which startled Walker out of his politeness 
forms the concluding paragraph of one of Cobden's great speeches."' I 
had forgotten, also, that moving passage in one of his pamphlets in which 
Cobden declared that, in place of many of the glittering mottoes of our 
forefathers, ' we must substitute the more homely and enduring maxim — 
cheapness, which will command commerce ; and ivhatever else is needful 
will follow in its train.' ^* 

Some of the criticisms one comes across of Cobden are, one must confess, 
a little hasty. As the organiser of the first Faculty of Commerce in a 
British University, I should be the last to deny the vast importance of 

»» W. of N., Bk. IV., ch. iii. (II., 68.) 

91 Bk. IV., ch. viii. (II., 244.) 

02 Bk. v., ch. i. (IJ., 333.) 

"■' Feb. 27, 1846. 

9^ Russia (1836), in Political Writings, p. 125. 


Price. And I by no means suppose that all the pleas for particular 
tariffs in order to keep up the workmen's standard of living have been 
well founded. All that I wish to say, after such a survey of a past period 
as we have been engaged upon, is that economic life has ceased to be as 
simple, if it ever were as simple, as those two great men, Adam Smith and 
Cobden, seemed to think it. It has not been so clear to the last half- 
century as it was to them that human well-being can be achieved by the 
application of one symmetrical cycle of principles. By the whole current 
of its industrial legislation the civilised world has protested against the 
all-sufficiency of cheapness. It has now embarked upon the double task 
of making a Living Wage a first charge upon the community and of giving 
Security a larger place in industrial life. This will be a harder business 
than to abolish old and often outworn restrictions on ' natural liberty.' 
Society has been so sorely disappointed in the hope that, if it sought first 
cheapness, all other needful things, like social peace, would be added to it, 
that it is in the mood to ' explore other avenues,' as the phrase goes — 
avenues as yet imperfectly charted. 

1924 N 






This Section of the British Association, over which I have the honour to 
preside, is concerned with the whole field of engineering, civil, mechanical 
and electrical. Within recent years the great developments which have 
taken i)lace in each of these branches have necessarily led to a high degree 
of specialisation, with the result that a man may have an expert knowledge 
of one branch but a very slight knowledge of the other branches ; in fact, 
the scope of a single branch is now so extensive and the amount of re- 
search work being done so great that it is impossible to keep abreast of the 
developments in one's own special subject unless one concentrates upon 
it to a degree that leaves little leisure for cultivating other branches of 
engineering. These considerations influenced my choice of a subject for this 
Presidential Address. As an electrical engineer, I felt that I should be 
expected to deal with some branch of electrical engineering — indeed, I 
should not feel comjjetent to discuss any other branch — but, in viev? of the 
facts to which I have referred, I decided not to deal in detail with any 
single section of the subject, but to review the past development and 
present position of the subject as a whole. 

The time for such a review is opportune. William Thomson, after- 
wards Lord Kelvin, the only man who has ever been elected three times 
(in 1874, 1889, 1907) President of the Institution of Electrical Engineers, 
was born on June 26, 1824. He was closely associated with the British 
Association and for sixty years took an important part in the meetings. 
He was President of the Association at the Edinburgh Meeting in 1871, and 
was several times President of Section A. I wonder what the members of 
the organising committee of Section G would think if the President, in 
addition to reading his address, offered to contribute twelve papers to the 
Proceedings of the Section : this is what Kelvin did as President of Sec- 
tion A at the Glasgow Meeting in 1876. I can find no record of his taking 
any part in the proceedings of Section G, although his brother, James 
Thomson, was President of the Section at the Belfast Meeting in 1874. 

If any one event can be regarded as the birth of electrical engineering, 
it is surely the discovery by Faraday in 1821 of the principle of the electro- 
motor ; that is, that a conductor carrjdng a current in a magnetic field 
experiences a force tending to move it. It is noteworthy that ten years 
elapsed before Faraday discovered, in 1831, magneto- electric induction ; 
that is, the principle of the dynamo. Four years later. Sturgeon added 
the commutator or ' uniodircctive discharger,' as he called it, and in 184-5 


Cooke and Wheatstone used electromagnets, wliicli Sturgeon had dis- 
covered in 1825, instead of permanent magnets. It was during the 
years 1865 to 1873 that the shunt and series self-excited dynamo, using a 
ring or drum armature and a commutator of many segments, finally 

The early workers in the field do not appear to have realised the 
intimate connection between the dynamo and the motor, for, although 
the i^rinciple was discovered by Lenz in 1838, it only appears to have 
become generally known that the same machine could be used for either 
purpose about 1850. The principle underlying the whole modern develop- 
ment of electrical engineering — viz., the generation of electrical power by a 
dynamo, its transmission to a distant point and its re -transformation to 
mechanical power by an electric motor— appears to have evolved about 
1873. An interesting light is thrown on the subject by a paper read before 
the Institution of Civil Engineers in 1857 by Mr. Hunt on ' Electromagnetism 
as a Motive Power.' In this paper the possibility of driving electro- 
magnetic engines — that is, electric motors — by currents derived from 
voltaic batteries was discussed in the light of Jacobi's discovery of the 
back-electromotive force in these machines. He concluded that power so 
generated would be sixty times as dear as steam-power, and that it would 
be far more economical to burn the zinc under a boiler than to consume 
it in a battery for generating electromagnetic power. The leading scientists 
and engineers who took part in the debate all agreed that electromotive 
power was unpractical and impossible commercially. William Thomson 
sent a contribution in writing which concluded with the following 
sentence: 'Until some mode is found of producing electricity as many times 
cheaper than that of an ordinary galvanic battery as coal is cheaper than 
zinc, electromagnetic engines cannot supersede the steam engine.' As 
S. P. Thompson says, ' Faraday's great discovery of 1831 notwithstanding, 
the real significance of the dynamo had not yet (in 1857) dawned upon the 
keenest minds of the time.' Six years before this, Thomson had suggested 
the experiment of driving a ' galvanic engine ' from a thermal battery, 
and had stated the problem in terms which show that he already had a 
correct grasp of the theory of the efficiency of the electric motor. 

It was at the Manchester Meeting of the British Association in 1861 
that Charles Bright and Latimer Clark read a paper proposing names for 
the principal electrical units ; the names were ' galvat ' for current, 
' ohma ' for electromotive force, ' farad ' for quantity, and ' volt ' for 
resistance. This paper led to the appointment of the celebrated Electrical 
Standards Committee of the British Association, which, after six years 
of strenuous work, produced the system now adopted internationally. 

One of the earliest applications of the dynamo was for lighting arc 
lamps in lighthouses ; in 1863 Thomson, writing to a friend on the relative 
merits of the Holmes direct-current and the Nollet alternating-current 
lighthouse machines, says : ' Thus Nollet escapes the commutator, a great evil, 
and gets a flame which does not burn one of the points faster than the 
other. The reverse of each proposition applies to Holmes. The commutator 
is a frightful thing . . . the thing to be done at the requisite speed is appal- 
ling. However, Holmes does it successfully. But I believe it cannot be 
done except theoretically without great waste of energy and consequent 
burning of contact surfaces. . . . But I believe a large voltaic battery tvill be 


more economical than any electromagnetic machine. I am not quite confident 
about this, but shall be so soon, as I am getting a large voltaic, and I shall 
soon learn how expensive its habits are, and multiply by the number 
required for a lighthouse.' This was thirty-two years after Faraday had 
discovered the principle of the dynamo. 

In after years Kelvin lost his dread of the commutator and championed 
direct against alternating current on every possible occasion. In 1879, 
when giving evidence before a Select Committee of the House of Commons 
on Electric Light, he even assured them that there would be no danger of 
terrible effects from the employment of electric power, because the currents 
would be continuous and not alternating ! 

The fifteen years following 1863 saw a great development of the dynamo, 
and in 1878, when a paper was read before the Institution of Civil Engineers 
on the improvements introduced by Siemens, Thomson made a remark, 
following a suggestion by Dr. C. W. Siemens, that showed that he had by 
this time thoroughly grasped the possibilities. He said that he believed 
that with an exceedingly moderate amount of copper it would be possible 
to carry the electrical energy for one hundred or two hundred or one thou- 
sand electric lights to a distance of several hundred miles. Dr. Siemens 
had mentioned to him that the power of the Falls of Niagara might be 
transmitted electrically to a distance, and he need not point out the vast 
economy to be obtained by the use of such a fall as that of Niagara or 
the employment of waste coal at the pit's mouth. In his evidence before 
the Select Committee referred to above he gave an estimate of the copper 
required to transmit 21,000 horse-power from Niagara to a distance of 
300 miles. 

In 1881 Thomson returned to the subject in his Presidential Address to 
Section A at York and said, ' High potential, as Siemens, I believe, first 
pointed out, is the essential for good dynamical economy in the electric 
transmission of power.' He mentioned 80,000 volts as a suitable voltage. 
In a paper before the Section he developed the now well-known Kelvin 
Law of the most economical cross-section of the conductor. In 1890 the 
American promoters of the project for utilising the power of Niagara turned 
to Thomson for his advice, and he became a member of the Commission 
of Experts. He was throughout stubbornly opposed to the use of alter- 
nating currents ; he wrote, ' I have no doubt in my own mind but that the 
high-pressure direct-current system is greatly to be preferred to alternating 
currents. The fascinating character of the mathematical problems and 
experimental illustrations presented by the alternating-current system 
and the facilities which it presents for the distribution of electric light 
through sparsely populated districts have, I think, tended to lead astray 
even engineers, who ought to be insensible to everything except estimates 
of economy and utility.' He was in a hopeless minority, however, in 
this view, and the Falls of Niagara were harnessed to two-phase alternators 
with an output of 3,500 kilowatts each. Kelvin was present at the meeting 
of the British Association held in this city in 1897, and shocked many people 
by saying that he looked forward to the time when the whole water of 
Lake Erie would find its way to the lower level of Lake Ontario through 
machinery ; ' I do not hope,' he said, ' that our children's children will 
ever see the Niagara Cataract.' Although he was apparently very much 
impressed with the success of the Niagara system, he was not converted 

ft— EN(iINEERINU. 181 

from his allegiance to direct currents, lor at his last appearance at the 
Institution of Electrical Engineers, in 1907, he said, ' I have never swerved 
from the opinion that the right system for long-distance transmission of 
power by electricity is the direct-current system.' 

The development of the dynamo during the seventies and the simul- 
taneous development of the incandescent lamp led to the general introduc- 
tion of electric light during the eighties. Attempts to make incandescent 
electric lamps had been made as early as 1841, when de Moleyns patented 
one having a spiral platinum filament, and in 1847 Grove illuminated the 
lecture theatre of the Royal Institution with such lamps, the source of 
power being primary batteries; but itwas not until 1878that the commercial 
development of the incandescent electric lamp was begun by Edison 
and Swan. 

One of the earliest complete house-lighting installations was put in by 
Kelvin in 1881. A Clerk gas-engine was used to drive a Siemens dynamo, 
a battery of Faure cells was fitted up, and every gas-hght in his house and 
laboratory at Glasgow University was replaced by 16 candle-power Swan 
lamps for 85 volts. He had to design his own switches and fuses, etc., 
for such things were almost unknown. 

For about twenty years the carbon-filament lamp held the field without 
a rival for interior illumination, and, although attempts were made to 
improve its efficiency by coating the filament with silicon, the plain carbon 
filament only gave way finally to the metal-filament lamp. One of the most 
interesting developments in the history of electric lighting was the Nernst 
lamp, which was introduced in 1897 ; the filament consisted of a mixture 
of zirconia and yttria, and not only had to be heated before it became 
conducting but also had to be connected in series with a ballast resistance 
in order that it might burn stably. The way in which these difficulties 
were surmounted and the lamp, complete with heater, ballast resistance, 
and automatic cut-out, put on the market in a compact form occupying 
little more space than the carbon-filament lamp was, in my opinion, a 
triumph of applied science and industrial research. The efficiency was 
about double that of the carbon lamp. About this time, however, a return 
was made to the long-neglected metal filament. The osmium lamp invented 
by Welsbach in 1898 was put on the market in 1902, to be followed two 
years later by the tantalum and tungsten lamps. The latter was greatly 
improved by the discovery in 1909 of the method of producing ductile 
tungsten and by the subsequent development of gas-filled lamps in which 
the filament can be run at such a temperature without undue volatilisation 
that the consumption is reduced in the larger sizes to 06 watt per mean 
spherical candle-power. This improvement of eight times as compared with 
the efiiciency of the carbon-filament lamp has led to the gradual replacement 
of the arc lamp even for outdoor illumination. The arc lamp was intro- 
duced at about the same time as the carbon-filament lamp, the Avenue 
de rOpera having been lit with Jablochkofi candles in 1878. The open 
arc was developed during the eighties ; the enclosed arc, giving long burning 
hours and thus reducing the cost of re-carboning, was introduced in 1893, 
and the flame arc in 1899. During the first few years of this century the 
flame arc was brought to a high stage of development and the consumption 
brought down to about 0"25 watt per candle-power, but the necessity 
of frequent cleaning to prevent the reduction of efficiency by dirt and the 


labour of re-carboning have led to its abainioii merit in favour of the less 
efficient filament lamp. 

Before leaving the subject of electric lighting I would point out that it 
is remarkable that the first great application of electric power should have 
been for the production of electric light, since it is probably the least 
efficient of all its applications. The overall efficiency of a small power station 
supplying a lighting load and having therefore a very poor load factor 
would not be greater than about 6 per cent, from coal to switchboard, 
the steam-engine being, of course, the principal offender. Of the total 
power supplied to and radiated from a carbon- filament lamp not more than 
about 2 per cent, was radiated as light, so that the overall efficiency from 
coal to light was 2 per cent, of 6 per cent., which means that of every ton 
of coal burned at the power station with the object of producing light all 
but about 3 lb. was lost as heat at various stages of the transformation. 
Even now, with up-to-date steam plant and gas-filled lamps, the overall 
efficiency from coal to light is not equivalent to more than 40 to 60 lb. of 
coal out of each ton. The electrical engineer may derive a little comfort 
from the knowledge that the purely electrical links are the most efficient 
in the chain. 

Whilst on the subject of efficiency I might point out that the difference 
between the prices at which coal and electrical energy can be purchased 
by the ordinary citizen corresponds to the losses incurred in the power 
station ; that is to say that the cost of the generation and distribution of 
the electrical energy is covered by the better terms on which the power 
station can obtain fuel. In Glasgow the writer pays 51. per ton for anthra- 
cite to burn in a slow-combustion stove; taking the calorific value of anthra- 
cite at 9,000 kilowatt-hours per ton, which is equivalent to 14,000 British 
thermal units per lb., this works out at 7| kilowatt-hours for a penny. 
For electrical energy for heating and cooking purposes the writer pays a 
penny per kilowatt-hour. This ratio of 1 to 7| will correspond fairly 
closely to the overall efficiency of the power station. In view of the high 
efficiency and convenience of slow-combustion stoves, it is evident that 
electric heating cannot be expected to compete with them for continuous 
operation ; for intermittent heating the question is very different. 

Returning from this digression to the development of the direct-current 
dynamo, it may be noted that the drum armature now almost exclusively 
employed was invented in 1872 by von Hefner Alteneck, and gradually 
displaced the ring armature of Pacinotti and Gramme. Although Pacinotti's 
original ring armature was slotted, smooth armatures were preferred for 
many years, until the mechanical superiority of the slotted armature caused 
the disappearance of the smooth core with its wooden driving pegs which 
were employed to transmit the turning moment from the conductors to 
the core. The commutator and brushes were a great source of trouble, 
but by the gradual elimination of unsuitable material and by better design 
and methods of manufacture the commutator has been made a most reliable 
piece of apparatus. The difficulties of commutation, and especially the 
need of continual adjustment of the brush position, were largely overcome 
by the invention of the carbon brush by Professor George Forbes in 1885. 
It should be pointed out that the commutating poles, which have come 
into use so much in recent years, were originally suggested in 1884, and 
are therefore older than the carbon brush. 


The realisation of the idea of supplying electric current from a power 
station for lighting houses in the neighbourhood owed much to the energy 
and business ability of Mr. Edison. He exhibited his first ' Jumbo ' 
steam-driven dynamo in 1881, and installed two sets at Holborn Viaduct 
in the following year to supply current to neighbouring premises. The 
output of these sets was about 90 kilowatts at 110 volts, which was so 
much larger than anything previously constructed that the name ' Jumbo ' 
was applied to these sets. About 1890 the multipolar type began to replace 
the bipolar type for the larger sizes. The size of the single units employed 
in power stations gradually increased with the increasing demand, and 
by 1895 dynamos of 1,500 kilowatts had been installed. 

As in all other types of machinery, the output obtainable from a given 
size has been gradually increased by improvements in the electrical, 
magnetic, and mechanical properties of the materials employed, and by 
improving the design so as to remove ever further the limits imposed by 
heating, sparking, voltage drop, etc. The freedom from trouble of the 
enormous number of electric trams and trains, to take only one class, is 
a testimonial to the reliability of the modern direct-current motor. 

The alternator has had a more varied development than the dynamo, 
mainly because of the absence of the commutator. The necessity of keeping 
the brush gear stationary and accessible and therefore allowing the com- 
mutator and armature to rotate led to an early standardisation of type 
in the D.C. machine. In the alternator there was no such limitation, 
and whether the field system should be inside or outside the armature 
and which of the two should rotate were largely matters of choice. There 
are great advantages in having the armature, which usually carries a high- 
voltage winding, stationary, and the usual practice has been for the field 
system to rotate within the armature. The most striking and best-knovv)i 
exception is the umbrella type of alternator installed in the first Niagara 
power station, in which the field system rotates outside the armature. 
The design of alternators has been controlled to a large extent by the 
development of the prime mover. On the Continent of Europe the slow- 
speed horizontal steam-engine led to the construction of alternators of 
enormous diameter in order to get the necessary peripheral speed, the axial 
length being consequently reduced to a few inches. In several cases these 
machines reached such a height that the travelling cranes in the erecting 
shops were useless, and special tackle had to be erected in order to assemble 
the machines. In England the high-speed marine-type engine was generally 
preferred, and consequently the alternators had a smaller number of 
poles and a smaller diameter. All this has now been modified by the 
development of the steam turbine. 

Ferranti was apparently the first to suggest that the power station 
should be outside the city, at a point convenient for fuel and water supply, 
and that the power should be transmitted into the city by high-voltage 
alternating currents. In 1890 he built the Deptford Station for the London 
Electric Supply Company, and installed 1,000-kilowatt 10,000-volt alter- 
nators. This was the pioneer high-voltage underground cable transmission, 
and much was learnt concerning the peculiarities of alternating currents 
when transmitted over cables of considerable capacity. The following year. 
1891, saw the first long-distance transmission by means of overhead 
conductors in connection witli the eh'ctrical oxliibitioii at Frankfort -on- 


Main ; three-phase power was transmitted, at 8,500 volts, from a water- 
power station at LaufEen to Frankfort, a distance of 110 miles. 

This development of the use of high-voltage alternating currents 
followed the development of the transformer. Gaulard and Gibbs patented 
a system of distribution involving transformers in 1882, and, although 
their patent was upset in 1888 on the ground of its impracticability, the 
present method of using transformers for the distribution of electrical 
power was introduced in 1885, and shown at the Inventions Exhibition 
in London in that year. Although from 1890 onwards there has been a 
steady increase in the size of alternators and transformers and in the volt- 
age employed for long-distance transmission, the last few years have seen a 
really amazing increase in thesizeof the units employed. In 1913 the largest 
2-pole turbo-alternators had an output at 3,000 revolutions per minute of 
about 7,500 kilowatts ; such machines are now made up to 30,000 kilo- 
watts, and 4-pole alternators are running at 1,500 revolutions per minute, 
with an output of 60,000 kilowatts. This increase in size and in peripheral 
speed has been made possible by improvements, both in the material and 
in the design. With a bursting speed 25 per cent, above the running speed, 
the peripheral speed can now be raised to 150 metres per second. Improved 
methods of cooling and a better understanding of the various causes of 
loss in the armature have enabled the materials to be used at higher 
current and flux densities. 

This great increase in the size of units is not confined to the steam 
turbo-generator, as can be seen from the water-turbine sets recently added 
to the Niagara installation. Whereas the original Niagara turbines were 
of about 5,000 horse-power, the new ones have an output of 70,000 horse- 
power at the low speed of 107 revolutions per minute. 

The importance of cheap electric power has led to this great increase 
in the size of the units in the generating stations. Any slight difference of 
efficiency between a 10,000-kw. and a 60,000-kw. alternator is of little 
importance, and would certainly not counterbalance the decreased factor 
of safety due to concentrating the whole power supply in three or four 
large units, instead of distributing it between a dozen or more units. 
The reason for the adoption of the smaller number of large units lies 
almost entirely in the decreased capital cost per kilowatt of plant. In my 
opinion, however, there are many cases in which too much consideration 
has been given to this factor, and too little to the importance of a 
guaranteed continuity of supply. 

Of even greater interest than the growth in the size of the units in the 
power station is the development of the switch control and protective 
gear, which is such an essential element in the success of the modern power 
plant. In the early days of electrical supply all the switch-gear was mounted 
on slate panels in the engine-room ; then, as the power and voltage in- 
creased, the switches were placed above, below, or behind the board and 
operated by mechanical links ; then they were removed to another part 
of the building, each enclosed in its own fire-proof cubicle, and operated by 
means of relays. The modern high-power switch, like the transformer, 
is oil-immersed in its iron containing case, and is so robust and weather- 
proof that it needs no further protective covering, but can be placed in the 
open air. The insulated bushings through which the leads are taken into 
the case are the most vulnerable points, but constitute no insuperable 
difficulty at the present time. 


The development of these robust aud weatlier- proof switches and trans- 
formers has led to the introduction of the open-air sub-station in cases 
where alternating current has to be transformed from one voltage to the 
other, and there is consequently no running machinery. In generating 
stations also much of the controlling and transforming plant which was 
formerly housed in the building can now be placed outside, with consider- 
able saving on the cost of the building. 

In connection with the conversion of alternating to direct current, 
mention should be made of the mercury arc rectifier. Great improve- 
ments have been made in recent years, especially in Switzerland, and a 
number of high-power arcs have been installed in sub-stations. Although 
they have the advantage of doing away with running machinery, the 
modern rotary-converter is such a reliable piece of apparatus that it is 
very questionable whether it will be replaced to any considerable extent 
by the mercury arc rectifier. 

Until recently, the only means of producing a large amount of high- 
voltage D.C. power was by connecting a large number of carefully insulated 
dynamos in series, as in the well-known Thury system of power trans- 
mission. Within the last two or three years another method has been 
developed, viz., the so-called transverter, which consists of an arrange- 
ment of transformers and a system of rotating brushes, whereby a three- 
phase A.C. supply is converted into an almost steady continuous current. 
The first apparatus of this type to be exhibited is installed at the British 
Empire Exhibition at Wembley, and is designed to deliver continuous 
current at 100,000 volts. It can also be used for the reverse process. It 
would thus enable a three-phase generating station and a three-phase sub- 
station to be connected by a direct- current transmission line, thus avoiding 
not only the maximum voltage of li times the effective voltage, which 
was one of Lord Kelvin's objections to the A.C. system, but also all 
trouble due to the capacity and inductance of the line. Whether the dis- 
advantages of the transverter, when it is fully developed — it is yet in its 
infancy — will more than outweigh these advantages remains to be seen, 
but, apart from the transmission of power, the device may have many 

Electric traction represents one of the most important branches of 
electrical engineering. It shares with the petrol motor the distinction of 
having absolutely revolutionised the methods of transport within a single 
generation. In its origins it is nearly a century old, for attempts were 
made in the thirties to apply Faraday's newly discovered principle to the 
propulsion of vehicles, but, with very primitive motors aud primary 
batteries, these attempts were doomed to failure. The development of 
the dynamo and motor in the seventies opened the way to further 
experiments, and at the Berlin Exhibition in 1879 a line one-third of a 
mile long was shown in operation, a locomotive drawing three cars. The 
first regular line was open.ed to traffic near Berlin in 1881 ; it worked at 
100 volts and the current was collected from an insulated rail. Toronto was 
the scene of one of the earliest experiments in America; C. J. van Depoele, 
after some experiments at Chicago in 1882 and 1883, ran an electric 
locomotive in 1884 between the street-car system and the Exhibition in 

The difficulties were enormous. The carbon brush was not invented 


until 1885, and commutation in a reversible motor with copper brashes 
caused great trouble ; armature construction and winding was in its 
infancy ; the suspension of the motor and the method of gearing it to the 
car axles were problems which were solved only after much experience. 
Rapid progress was made after about 1887, and the closing years of the 
century saw an enormous development, the elimination of horse tram-cars 
throughout the world and the electrification of a number of city and 
suburban railways. 

Of the various systems of collecting the current, only two have 
survived for street-cars, viz., the usual overhead wire and the exceptional 
underground conduit ; in the case of railways there is no necessity for a 
conduit and the conductor rail is carried on insulators above the ground- 

Although 500- volt D.C. supply has been standardised for street tram- 
ways, the relative merits of D.C. and A.C. for electric railways has been a 
burning topic for over twenty years, and is now perhaps more burning 
than ever. It is somewhat akin to the battle of the gauges in the early days 
of steam railways, for it involves in many cases the jjroblem of through 
running, if not now, in the not very distant future. Although the three- 
phase system was successfully installed in Northern Italy, it has grave 
disadvantages, and the battle now is confined between direct current at 
an increased voltage of, say, 1,500 to 2,000 volts, and single- phase 
alternating current. In the latter case there is, moreover, a further 
question as to the best frequency to adojrt, this being usually either 
25 or 16f. The development of the A.C. commutator motor to the 
stage where it was applicable to traction took place during the first few 
years of this century, and, although in itself it is inferior to the D.C. motor; 
it introduces so many simplifications and economies in the transmission of 
the power from the generating station to the train that experts are very 
divided as to the relative merits of the two systems for main-line electrifi- 

I can only just refer to the applications of electrical power to chemical 
and metallurgical processes. Some of these are purely electro-chemical, 
others are purely thermal, w^hile in many processes the electric current 
performs the double function of melting and electrolysing. The possibility 
of electroplating was discovered as early as 1805, but the commercial 
application of electro-chemistry on a large scale was im]>ossible before the 
development of the dynamo. Within the last thirty years the provision of 
an abundant supply of electrical power has led to the creation of enormous 
electro-chemical industries ; I need only instance the production of 
aluminium, carborundum, and calcium carbide. These industries have 
usually been established near a hydro-electric jjlant and provide a load 
of very high load-factor. 

I turn now to what may be called both the earliest and the latest appli- 
cation of electricity; that is, its use for transmitting intelligence. One of the 
greatest factors in the development of our modern life has undoubtedly 
been the network of wires and cables which has spread over the whole 
earth, making possible an almost instantaneous transmission of intelligence 
and interchange of opinions. In the early days of electrical science the 
discovery of a new property of electricity was followed by attempts to utilise 
it for this purpose. As early as 174r) there are records of the use of frictional 


electricity for the purpose, and distances up to four miles were tried. 
In 1774 Lesage of Geneva proposed 26 wires in earthenware ])ipes with pairs 
of pith-balls at the end of each wire, which Hew apart when the conductor 
of a frictional machine was brought near the other end of the wire. A 
current of electricity was unknown until Galvani's discovery in 1789, and 
Volta's pile was first constructed in 1792. Carlisle in 1800 found that 
water was decomposed by passing the current from a Volta pile through 
it, and this was the basis of the telegraph proposed by Sommering in 1809, 
in which 26 wires ended in 26 metallic points arranged in a row along the 
bottom of a kind of aquarium. By means of a lettered keyboard at the 
sending end the current could be applied to any wire, and a stream of 
bubbles caused to rise from the appropriate point, each point being duly 
labelled with its appropriate letter. The magnetic effect of the electric 
current was discovered in 1819, and immediately replaced the previous 
methods in efforts to develop an electric telegraph ; except for the attempts 
to make a high-speed chemical telegraph, all subsequent telegraph systems 
have employed the magnetic effect of the current. A great many of the 
fundamental inventions of telegraphy were made in the thirties ; the list 
includes the needle instrument of Cooke and Wheatstone, the sounder of 
Henry, the dot-and-dash inker of Morse, and the use of the earth as a return 
by Steinheil. Although the needle instrument is now obsolete, the sounder 
and Morse inker are still commonly employed. Many have been the devices 
for increasing the amount of traffic which can be worked over a single line, 
either by the simultaneous use of the line by a number of operators, as 
in the quadruplex and multiplex systems, or by punching the messages on 
paper tapes, which can then be fed into an automatic transmitter working 
at a speed ten to twenty times that attainable by a manual operator. In 
the most up-to-date systems the perforation of the tape is done by the 
operators working an ordinary typewriter keyboard, and the received 
message is printed in ordinary type, a single wire carrying eight messages 
simultaneously, four in either direction, at a speed of 40 words per minute. 

The need for telegraphic communication between countries separated 
by water was so much the greater because of the slowness of other means of 
communication, but the difficulties in laying and maintaining 2,000 miles 
of insulated wire on the bottom of the sea must have appeared almost 
insuperable to the early workers ; fortunately, however, there were men 
who had the necessary vision and courage. The flimsiness of the early 
cables suggests that the pioneers underestimated the magnitude of the 
problem which faced them, which was perhaps fortunate. A cable was 
laid between Dover and Calais in 1850 ; it lived only a single day, but it 
was replaced in the following year by a successful cable. 

The first cable was laid across the Atlantic in 1858, and, although in 
the light of our present knowledge we know that it could not have had a 
very long life, its failure after a few weeks of preliminary communication 
was primarily due to misuse owing to the ignorance of those in charge. 
Although much costly experience had been gained in the laying of cables 
in various parts of the world since this first attempt to span the Atlantic, 
the success of the second Atlantic cable in 1866 was largely due to the 
scientific ability of Kelvin and to his enthusiastic and untiring application 
to the project at every stage of the manufacture and laying of the cable. 
In addition to this, he not otiiy designed the receiving instruments, but 


superintended their manufacture in Glasgow and their installation and 
operation. The success of the Atlantic cable was to a large extent a 
personal triumph for Lord Kelvin. Although numerous improvements 
have been made in the details of cable manufacture and in the transmitting 
and receiving apparatus, no outstanding change has been made in recent 
years in the methods of submarine telegraphy. 

Turning to another branch of electrical communication, it is no 
exaggeration to say that modern business life has been revolutionised by 
the telephone, which will shortly celebrate its jubilee, for it was in 1876 
that Graham Bell invented the magnetic telephone receiver, although others, 
notably Reis, had been working at the problem since 1861. Bell showed 
his telephone in operation at the Philadelphia Centennial Exhibition in 
1876, and Kelvin, who was one of the judges, brought one back with him 
and demonstrated it to Section A of the British Association, at its meeting 
in Glasgow in the autumn of 1876. 

A successful telephone system requires much more than efficient 
transmitters and receivers, and the great development which has taken 
place has been largely a matter of improvement in the design of the many 
elements that go to make up a telephone exchange. The modern manual 
central-battery exchange, in which one has only to lift his receiver to call 
the operator and be connected in a few seconds to any one of 10,000 other 
subscribers, is a marvel of ingenuity and construction. But this is now 
gradually being replaced by the greater marvel of the automatic system, 
in which the operator is eliminated and the subscriber automatically 
makes his own connection to the desired subscriber. Attention should be 
drawn to two outstanding inventions in the actual transmission of telephony 
over long distances, viz., loading and repeaters. It was Oliver Heaviside 
who in 1885 proposed to improve the range by increasing the inductance 
of the line. Although this revolutionary suggestion fell on deaf ears for 
fifteen years, it ultimately proved to be one of the great inventions of 
telephony ; it is of special importance in underground and submarine 
telephone cables, the electrostatic capacity of which otherwise seriously 
limits the range. The other outstanding novelty is the introduction of 
repeaters at intermediate points in long telephone lines. These repeaters 
are specialised types of low-frequency amplifiers ; they were made commer- 
cially possible by the invention and perfection of the three-electrode 
thermionic valve. The attenuated speech currents arriving at the end of 
a section of line are amplified and thus given a new lease of life before being 
passed on to the new section. By using a large number of such repeating 
stations, telephonic communication has been established between New 
York and San Francisco. But in addition to making such long-distance 
communication possible, the use of repeaters enables medium distances 
to be bridged by relatively cheap lines of high attenuation. 

One important application of telephony which is not generally known 
is in the control of transport ; the advantage to be gained by controlling 
the whole railway traffic of a large district from a central office need only 
be mentioned to be appreciated. 

Turning now to radio telegraphy and telephony, one cannot but marvel 
at the rapidity of its development and the inroad that it has made during 
the last two or three years on the domestic life of the whole civilised world. 
The theory of Clerk Maxwell in 1864 and the laboratory experiments of 


Hertz in 1888 found their first practical application in Marconi's Italian 
experiments in 1895 and his demonstrations in England during the follow- 
ing year. Much of the rapid progress was due to his perseverance, 
vision, and courage in perfecting apparatus for short- distance work, and 
simultaneously experimenting over long distances, and thus, in the year 
1901, settling by actual demonstration across the Atlantic the vexed 
question as to whether the waves would pass around the earth over dis- 
tances of several thousand kilometres or go off into space. 

The accomplishment of long-distance communication bristled with 
difficulties, largely due to unsuspected atmospheric effects which are still 
little understood ; but such progress has been made and is continually being 
made that one dare not now adopt an incredulous attitude to the wildest 
dreams or forecasts of what is to be accomplished by ' wireless.' The 
commonplace facts of to-day would have appeared beyond the bounds of 
possibility ten or twenty years ago. 

I have attempted to trace, in a necessarily somewhat superficial, but, 
I trust, none the less interesting, manner the development during the last 
hundred years of some of the principal applications of electricity to the 
service of mankind. In preparing this address, I have been greatly im- 
pressed by the enormous advances made, especially during the last thirty 
or forty years, in the mastery of man over the resources of nature, and in 
the use of these resources to the amelioration of the conditions of life. 
By theaid of electricity the energy of the coal or of the lake or river a hundred 
or even two hundred miles away is transmitted noiselessly and invisibly 
to the city, to supply light and warmth, to cook the food, to drive the 
machinery, to operate the street-cars and railways. 

By its aid one can flash intelligence to the most distant part of the 
globe, hold conversations with friends hundreds or even thousands of miles 
away, or sit in one's home and listen to music and lectures broadcast for 
the entertainment or instruction of all who care to equip themselves with 
what may almost be regarded as a new sense. Whereas thirty years ago 
a ship at sea was completely isolated from the life and thought of the world, 
it is now in continuous communication with the land and with every other 
ship within a wide range. 

In no branch of electrical engineering, however, is there any suggestion 
of having reached finality ; on the contrary, rapid development is taking 
place in every direction, and we can look forward with confidence to an 
ever-increasing application of electricity to the utilisation and distribution 
of the natural sources of energy for the benefit of mankind. 






A Canadian meeting of the British Association for the Advancement of 
Science is of sj)ecial interest to Section H, since it was in this Dominion 
that it first entered upon a separate existence forty years ago. 

In his Presidential Address to the Section at the Winnipeg Meeting, 
Professor Myres asked the question ' What happens to Englishmen in 
city " slums " ? ' or, in other words, how are the peoples of Britain adapting 
themselves to modern conditions ? Are these conditions producing modi- 
fications in the racial constitution and qualities of the nation ? The matter 
is one of importance to the older country, for over three-quarters of the 
population now reside in urban districts, and to the newer, since in the 
course of time industries must concentrate in favourable localities and 
close aggregates of population necessarily arise. 

The trend of events can be followed in outline from demographic data 
from about the fourteenth century, though the records are scanty until the 
nineteenth century. The main factors are urbanisation and industrialism, 
the combined effects of which can be seen best, though in an exaggerated 
form, in those individuals who follow certain trades, such as the textile in- 
dustry, which associate dense aggregation with, even at the best, unhealthy 
conditions of occupation. 

Indoor trades and factory life introduce very different physiological 
conditions from those under which the young peasant has his being. These 
factors tend to depress the vitality of the incomer from the country, while 
those born in the industrial township would be exposed to urban conditions 
throughout early as well as adult life, and have the further handicap in 
infancy of the lack of care inevitably associated with the factory employ- 
ment of the mothers. 

In addition, selection may in time sensibly modify the distribution of 
the various racial elements of the population. Psychological factors, too, 
come into play, for some types seem to prefer the freer life of the open 
spaces and leave a district as it becomes more densely settled ; while 
others, who have no love or aptitude for solitude, migrate into the growing 
towns. The early settlers of the North American continent were drawn 
largely from areas occupied by Nordic peoples whose early history was 
that of hunting and fighting communities. As the eastern edge of the 
continent became settled, it was this type that was largely represented 
in the pioneers of the West. 


At first siglit, the answers to the questions seem to be unsatisfactory, 
and it is coniiuon to hear of the physical deterioration of the people, though 
such pessimism is of long standing, being found as early as ' The Reflec- 
tions of an Egyptian Sage.' It seems worth while to inquire if the change 
is real and permanent. 

The most alarming data in regard to the position in Britain come from 
the Report of the Ministry of National Service on the findings of the 
recruiting boards during the last yeara of the European war. The recruits 
were graded into four categories, from those who exhibited the full normal 
standard of health and strength and a capacity to sustain severe exertion, 
through those with various partial disabilities, down to those totally and 
permanently unfit for any form of military service. The ages of those 
examined extended from eighteen to fifty, and the report therefore com- 
prised such a study of a selected sample of a people as had never before 
been attempted. The survey of some two and a half million men showed 
them to be graded in the proportions ' : — 

Grade I. 
Grade II. 
Grade III. . . 
Grade IV. . . 

36 per cent. 
23 per cent. 
31 jier cent. 
10 per cent. 

Grave disappointment followed 

this discovery 

but a reassuring 
comment was made by the Commissioner for Yorkshire,^ who pointed 
out that grading for military purposes must, in many essentials, differ 
from grading in respect to fitness for civilian life, which, after all, is the 
factor of most permanent importance to a nation. For example, an exag- 
gerated flat foot might render a man useless for general military service, 
and yet for civilian purposes be of trifling import. The same would apply 
to many minor disabilities that increase with age. No previous data had 
given any idea of the extent of age changes in efficiency, though it was well 
known that the period of maximum efficiency in active games was the ages 
under thirty. It is therefore not surprising that the numbers fit for severe 
strain should fall off after that age or that relatively few over forty should 
be fit for effective military service. There is no reason to think that this is 
in any way a new phenomenon associated with urbanisation, or that a similar 
census in past centuries would have yielded any better results ; indeed, 
data on health to be submitted on subsequent pages suggest that larger 
numbers of fit individuals at the higher ages exist now than in any past 
time. Another and more serious criticism of this report as an accurate 
survey of the whole state of the population of Britain rests on the fact that 
it was only undertaken after some years of war, when the physical pick of 
the nation had already voluntarily enlisted. 

The more valuable data are contained in the records of some 260,000 
youths born in 1900, about two-thirds of the total number attaining the 
age of eighteen in 1918, the proportion in their case being (in round 
numbers) " : — 

Grade I. . . 65 per cent. 

Grades II. & III. 30 per cent. 

Grade IV. . . 5 per cent. 

1 Report, Minislry of National Service, vol. i., p, 4. 
» Ibid. p. 109. ' Ibid. p. 22. 



These figures are nearer to expectations, although unsatisfactory for 
those who aim at 100 per cent, efficiency. 

The proportions of Grade I. varied from 80-85 per cent, in rural areas, 
over 75 per cent, in mining areas, 72 per cent, in the suburbs around London, 
down to 49 per cent, in the crowded industrial areas of Lancashire. Some 
of the Scottish returns in particular indicate the price of urbanisation, 
at the ages of eighteen to twenty-one.'' 








Grade I. 
„ II. 
„ III. 
„ IV. 











There is nothing in these figures to suggest that the British people 
have degenerated more than other nations. The German pre-war figures '' 
showed 72 per cent, fit or prospectively fit for service and 28 per cent, less 
fit or unfit for service, with the same contrast between the rural and urban, 
the agricultural and the textile areas, as is noted in Britain ; while the 
United States rejected 21 per cent, of their draft of men from twenty-one 
to thirty years of age.® In the latter country the higher proportion of 
rejections were from the urbanised and more industrial States, and the 
lowest from the more rural and sparsely populated areas of the West. 

In general it may be noted that many of the causes of low grading 
at all ages were defects which would readily yield to treatment in their 
initial stages, and that great advantage would arise from the establishment 
of a social tradition in favour of early treatment, and in particular against 
septic mouths and uncared-for teeth. The younger members of the 
community are greatly in advance in these respects, and it is clear that 
the school, and its ancillary accompaniments, must now be reckoned 
among the most powerful of public health agencies. 

Actual data on stature are very sparse in the reports of the recruiting 
boards ; the figures are below those of the British Association Committee 
taken as a whole, but differ little if at all in those areas in which corre- 
sponding classes of the community can be compared, while the relation 
between physique and occupation is of the same order in the two reports. 
The Ministry returns show that a large number of the adult male population 
examined as conscripts in 1918 had statures between 64 and 67 inches, but 
the average figure obtained has little significance as an index of the whole 
pre-war population, since a large proportion of the tall stock had already 
enlisted. The returns from the United States ^ show that the average 
stature of the members of their draft who had been born in Britain was 
Scottish 67-9, English 67-7, a distinctly higher figure, probably to be 
explained by the greater tendency of the taller stock, the Nordic, to 
emigrate to fresh fields. The lowest statures quoted by the recruiting 

* Report. Ministry of National Service, vol. i., p. 132. 

* Rep. Inter-departmental Committee on. Physical Deterioration, vol. iii., p. 5fi. 
' ' Defects found in Drafted Men.' Washington. 

' Report of Medical Dept., U.S.A. Army, vol. xv., Pt. I., p. 106. 


boards were found among the casual labourers and the textile workers, 
who had been subject to bad conditions of environment. 

The returns from the School Medical Service show that stature is on the 
whole greater in England and Wales to the south of a line drawn from the 
Severn to the Wash, with an extension northward to include Lincolnshire 
and the East Riding of Yorkshire ; in addition, scattered areas containing 
many tall children occur in Westmoreland, on the coast of Cumberland, 
in the far north of Lancashire, in the hilly districts of Staffordshire and in 
Merioneth. This line of demarcation clearly marks off the industrial from 
the rural districts, though it also largely coincides with areas of former 
Saxon, Danish and Norwegian occupation. The children in factory towns 
and mining areas are in general definitely shorter than those in rural 
districts. Arthur Greenwood," considering the returns from a large 
number of education authorities, found that the results could be expressed 
in terms of those for all England and Wales with the following results : — 

All England and Wales 100 

Rural parts of County Areas ..... 102-4 

Urban parts of County Areas ..... 100-5 

London 99-6 

Manufacturing Towns : 

Glamorgan and Monmouth (Coal and Iron Towns) . 98-5 


Yorkshire Woollen Towns 

Lancashire Cotton Towns .... 
Staffordshire Pottery and Hardware Towns 
Durham and North-East Coast (Coal and Iron) 

These findings agree closely with those of the recruiting boards, and a 
comparison of the two shows that the inferiority in the textile towns 
becomes more noticeable after the school age. In London* the physique 
is best on the whole in the suburban areas on the higher ground, and is 
worst in the poorer districts to be found in the central areas, along the 
Thames flats and in the valleys of the small streams that once flowed 
across the site of the present county. In Scotland the best physique is 
to be found in the rural areas, except in the Western highlands and islands 
where environmental factors other than urbanisation have tended to stunt 
growth and the racial type differs. As in England, industrial districts are 
below the average. 

The best physique is found in the great public schools, then in order 
come the secondary schools, the trade schools and the ordinary elementary 
schools ; these correspond pretty well to the leisured and professional, 
the commercial, the artisan, and the factory and labouring classes, 
respectively. The stature of the children from the better-class schools, 
many of whom present Nordic traits and all of whom have been brought 
up in a favourable environment, is equal to any in the world. The general 
average for all types of schools is, however, below that of the children of 
British descent in the Dominion or the Commonwealth. The advantage 
of the latter supports the opinion that the emigrant stocks from Britain 
contained a large proportion of Nordic elements, and also suggests that 
the children flourish under the new environment. 

' Greenwood, Health and Physique of School Children, pp. 27-28, and Appendix A. 
• L.C.C. Report of Medical Officer (Education), 1910, pp. 131-133. 


Even the worst estimates of the present-day physique, when compared 
with such records as exist of the former inhabitants of the British Isles, 
afford little evidence of a deterioration of stature in members of a particular 
racial type, but rather of a change in their relative proportion in the total 
population. In neolithic times, so far as can be gleaned from skeletal 
remains, the average stature of adult males was about 63 inches with a few 
taller individuals interspersed, who were perhaps of the ruling caste ; the 
Saxons averaged about 66 inches, the Norwegians and Danes were a little 
taller. The stocks in each district remained in comparative isolation until 
the advent of roads and railways and the demand for labour in new areas 
caused a greater degree of intermixture. Even now, rural areas which 
had originally a predominant Nordic occupation contain a taller and fairer 
population ; in the cities the degree of intermixture has proceeded to such 
an extent that there is relatively little relation between stature and hair 
colour. Throughout the mediaeval period, stature remained little affected 
so far as can be judged from clothes, implements and armour, which would 
suit the larger number of the present-day people and would indeed be too 
small for the better built. In the eighteenth century there were many 
recruits whose stature was only about 63 inches. 

Records of children of Lancashire operative and labouring classes, 
taken in the second quarter of the nineteenth century, when compared 
with similar figures at the present day show little change until the last few 
years. Since the initiation of the School Medical Service, it has become 
evident that a gradual improvement is in progress. In London elementary 
schools there has been a gain of a full half -inch in stature since 1904, while 
in the public schools average gains of an inch or more are recorded. The 
changes in weight are even more general and significant. It is noteworthy 
that the average weight of the crews in the Oxford and Cambridge boat 
race, who were always chosen from the pick of the undergraduates, has 
increased nearly a stone in the last sixty years. 

Comparisons which have been made between children who have 
suffered from illnesses and those who have had none of importance, show 
the greater stature of the latter class and indicate one of the ways in which 
urbanisation exerts malign effects and also the advantages of care in 
childhood. Many children fail to attain their full stature on account of 
morbid factors which may act on the growing bones directly, as in rickets, 
or indirectly through malnutrition resulting from infectious ailments, 
catarrhs or actual privation. The 2)redominant factor in the determination 
of stature is of course heredity, but where the soil and climate are unpro- 
pitious and poverty prevails the physique of all the inhabitants is depressed 
irrespective of their racial type. Collignon and others have shown that 
those removed from such districts in early life recover their normal stature, 
while those brought into the unfavourable surroundings are proportionately 

Taking a more general survey, the health of a people under varying 
conditions may be measured by the variation in the duration of life as to 
which data are available for recent years and to some extent for the past. 
The duration of human life appears to have steadily increased from the 
earliest times. So far as can be judged from skeletal relics, early man did 
not live much beyond early adult life, though some indi\'iduals, such as the 
old man of Cromagnon, attained to old age. The words of the Psalmist 



suggest that in his time the duration of life of those who survived the 
vicissitudes of infancy and early adult life was much the same as at the 
present day. The great gain has been that more now live to middle age 
or beyond. Macdonell and Pearson analysed the data on mummy cases 
from the time of the Roman occupation of Egypt ^" and the 'Corpus 
Inscriptionum Latinarum ' of the Berlin Academy," which gives the age 
at death of some thousands of Roman citizens who had lived either in the 
City of Rome or the provinces such as Africa, at the early part of the 
Christian era, and were able to construct rough life tables indicating the 
probable expectation of life at different ages. These may be compared 
with tables constructed by Halley on the data in the bills of mortality 
of seventeenth-century Breslau, by Milne for eighteenth-century Carlisle,^" 
and with those constructed on modern census and registration data. 

Average Expectation of Life for Each Person Living at the 
Beginning of the Age Interval, in Years. 

Place and 











17 Cent. 

IS Cent. 






























42 I 














12 j 







4 I 


The results show such an increase in the expectation of life at the 
earlier ages as to emphasise Karl Pearson's comment on the Egyptian data : 
' either man must have grown remarkably fitter to his environment or else 
he must have fitted his environment immeasurably better to himself.' 
Even in the early days, however, the disadvantages of the more urban 
surroundings are evident in the lower span of life in the Imperial City as 
compared with the Roman provinces. That a similar difference existed 
in the British Isles is certain, though from lack of data detailed comparison 
is impracticable until the last century. 

The expectation of life varies from class to class much as does physique, 
being greater for the professional classes than for the agriculturist, for the 
agriculturist than for the miner, while the latter in turn is a better life than 
the tailor or the textile worker. From life tables based on the mortality 
experience of the years 1911-12, the expectation of life appears to be 
greater in the South than the North of England and to vary in each area 
with the degree of industrialism and urbanisation. It also seems when 
the data as to numbers of survivors are plotted on a map that there is a 
greater expectation in those areas which, at any rate until recent times, 
were occupied by a predominantly Nordic population. 

1" Pearson, K., Biometrika, vol. i., pp. 261-264. 

" Macdonell, W. R., Biometrika, vol. ix., pp. 366-380. 

12 Pearl, R., Biology of Death, pp. 79-101. 

" Unpublished data by courtesy of B. Spear. 



Expectation of Life ix England and Wales, 1911-1912.'* 
















General health has often to be estimated from the records of mortality, 
though it must be remembered that morbidity is much greater than 
mortality and that the after-effects of injury or disease may long affect the 
physique of the sufferer. Lethal agencies are sometimes local, sometimes 
widespread in their action, and may at times exert a selective action on the 
population affected. Tertullian long ago maintained that earthquakes 
and wars, famine and pestilence have to be regarded as a means of pruning 
the luxuriance of the human race. These vary greatly in their mode of 
action and powers of selection. Earthquakes need not be considered so 
far as England is concerned during the historic period. 

War in early culture might occasionally wipe out a whole population, 
but more often the skilful and strong survived ; in modern war the 
selection favours those whose physique does not permit of active military 
service and is thus opposite in tendency. This indeed has been offered as 
a partial explanation of the poorer physique recorded of those French 
conscripts who had been born during the wars at the beginning of the last 
century, when the fittest of the adult male population were absent or 
killed. War acts more lethally through the social disorganisation, and the 
consequent famine and disease, which follow in its train, than through any 
casualties in the field ; from these direct experiences on its own soil, 
England had been singularly free since the Norman period. Philip de 
Comines remarked ' England has this peculiar grace that neither the 
country, nor the people, nor the houses are wasted or demolished ; but 
the calamities fall only on the soldiers and especially on the nobility.' " 
The wider effects of war were only felt, and then but locally, in the cam- 
paigns of the Stuart reigns, though there was great suffering earlier in the 
forays on the marches of Wales aiid Scotland. Thanks perhaps to the 
great demand for labour and to the separation allowances, as well as to 
the seat of action being abroad, the recent war has exerted no obvious 
harmful effects. The children have been well nourished and there was no 
great increase of defective children, such as had been anticipated by some, 
even in the areas most exposed to air raids. There was, it is true, an 
increase in the number of children who were troublesome and educationally 

** Supplement to 75th Annual Report of Registrar- General of England and Wales, 
Part II., p. 34. 

^^ Philip de Comines ed. Godefroy, Memoires, III., p. 155. Quoted by 
L. Creighton, Hist, of Epidemics in Britain, vol. i., p. 224. 


backward, but on examination it was clearly seen that these features were 
not due to innate characters but to truancy and lack of discipline during 
the absence of their fathers. 

Famine took its toll in Western Europe in the mediaeval period, but 
England was the country in which the mass of the people soonest attained 
to fairly constant comfort. A poem, attributed to Henry of Huntingdon, 
contains the stanza : 

' Anglia terra ferax et fertilis angulus or bis 

Externas gentes cousumptis rebus egentes 

Quando fames laedit, recreat et reficit.' " ^' 

This was a great contrast to France, which repeatedly suffered from long 
years of famine, but England certainly had occasional periods of scarcity 
at long intervals. Creighton,^^ it is true, draws attention to a mediaeval 
saying ' Tres plagae tribus regionibus appropriari solent, Anglorum fames, 
Gallorum ignis, Normannorum lepra ' ; probably, however, the English 
were so used to good feeding that they indulged in the national habit of 
grumbling over a scarcity that elsewhere would have been taken as a 
matter of course. The ' Vision of Piers Ploughman ' i' seems to bear this 

' And tho wolde wastour nouzt werche, but wandren aboute 
Ne no begger ete bred that benes Inne were. 
But of coket or clerematyn or eles of clene whete : 
Ne none halpeny ale in none wise drinke. 
But of the best and the brounest that in burghe is to selle.' 

While Harrison in his ' Description of Britain ' -" quotes a Spaniard in 
Queen Mary's day as saying ' These English have their houses made of 
sticks and dirt, but they fare commonly as well as the king.' In modern 
times the only state of affairs which could be compared with events in the 
mediaeval period is the Irish potato famine, in which actual starvation was 
accompanied, as of old, by outbreaks of fever and an abandomnent of effort 
from sheer despair. In general any morbid influences on nutrition arose 
rather from a seasonal scarcity of certain essential articles of diet than from 
famine in the ordinary acceptation of the term. 

Disease, throughout the historic period, must have been the most 
lethal of all the morbid agencies. There is nothing to suggest that there 
are important diseases to-day from which our ancestors were free, with the 
possible exception of syphilis, which is first recorded at the very end of the 
mediaeval period. Anglo-Saxon leechdoms reveal that there were then, as 
now, cancer and consumption, gout and stone, the falling sickness and 
St. Vitus' dance, fevers, catarrhs and rheums. Even congenital defects were 
noted, Giraldus Cambrensis ^^ in his ' Topographia Hiberniae ' referring 
to the many individuals who were born blind, lame, maimed or having some 

1' De praerogativis Anglia".. Quoted by Higden, Polychronicon, Rolls ed., ii., 18. 
*' Creighton, I.e., vol. i., p. 8. 

*' L.c. vol. i., p. 52, with reference to Fuchs Das he.ilige Feiier im MillelaUer 
Heckei^ a Annalen, vol. 28, p.l. This latter cites Alberici Chronic, Bouquet, xii., f>90. 
^' W illia,m 'L&ngla.n.d, Piem the Plowman, passusvi., 1. 304-308. Skeat's ed.,p. 77. 
^^ William Harrison, Elizabethan England, the Scott Library edition, p. 114. 
-* Rolls ed., vol. v., p. 21. 


natural defect. On the other hand, certain of the scourges of our ancestors 
have practically disappeared, especially some of the infectious diseases. 
Leprosy and plague long ago ceased their ravages, typhus and famine 
fever vanished, save for isolated cases in later Victorian times, enteric 
fever has lessened nearly to the vanishing point, and even infantile 
diarrhoea is becoming less year by year. Most, if not all, of these diseases 
may be communicated by animal agencies, either by direct inoculation 
from bites or by secondary contamination. The louse, the bug and the 
flea, common until recent years, are succumbing to the newer tradition 
and meaning of cleanliness which has followed universal education, the 
medical inspection of scholars, and the action of public health authorities ; 
the fly, an indirect agent, is being eliminated by improved sanitation, and 
the gradual disappearance of horse transport in our cities. As the changes 
proceed more rapidly in the towns the approximation of their health 
conditions to those in rural areas follows. 

Epidemic diseases have always attracted more notice from the historian 
owing to the wide extent of the resulting evils, so that much is written 
concerning the plague, the sweat, gaol fever and smallpox compared with 
more common disorders of life. Some of these have appeared in earlier 
days to exert some selective influence, though this selection depended 
rather on the mode of transmission of the disorder. Any disease trans- 
mitted, whether by vermin or from case to case, would be more prevalent 
under conditions in which the population were closely massed, and at 
periods or under conditions in which either the facilities or the sentiment 
for cleanliness were lacking. The plague, save in its first pandemic out- 
bursts as the ' Black Death,' was mainly a disease of the poorer classes in 
the towns, in each epidemic affecting especially the worst housed, worst 
fed and least cleanly. Sporadic outbursts in rural areas followed the intro- 
duction of infection from without, as was well recognised by villagers who 
forcibly endeavoured to prevent the entrance of travellers from affected 
areas. Gradual changes in habits and domestic furnishing which reduced 
the breeding- places of rats and fleas were followed by the extinction of the 
plague. The sweat, it was noted in Tudor times, differed in its incidence ;^^ 
Kock said of the 1529 pandemic ' the poor people and those living in 
cellars and garrets were free from sickness,' while Renner noted ' it went 
most among the rich people.' This tradition, or a continuance of similar 
phenomena, must have remained, for we find in ' Measure for Measure ' "^ 
Mistress Overdone says, ' Thus, what with the war, what with the sweat, 
and what with the gallows, I am custom-shrunk.' It was noted over a long 
period that whereas typhus, gaol fever, and the like were always present 
among the poorer classes, the greater mortality followed outbreaks 
among healthier individuals, who had lived an open life, such as soldiers 
brought back to barracks after a campaign in the field, sturdy felons newly 
flung into gaol, or, as in the Irish famines, magistrates and relief workers 
whose duty carried them into the haunts of the disease. In the case of the 
' Black Assizes,' when judges and jurors succumbed but the prisoners 
escaped lightly, the phenomenon was ascribed to the latter being inured to 

2- Creighton, I.e., p. 268, with reference to Gruner, Scriplores de sudore Anglico 
superstite-s, pp. 444 -4 4S. 
23 Act i., So 2 


the stencliL's of the cells, though the modern explanation would suggest that 
they might have acquired immunity from previous and possibly slight 
attacks. It has been argued that such eimlemic diseases served a useful 
purpose in that they removed weaklings, but the type selected by this test 
of relative immunity to typhus or gaol fever is not one to be commended 
on account of its mental or physical traits. The general statement is 
Jiowever open to doubt ; Ballard -■' reporting on the Leicester outbreak 
of infantile diarrhoea in 1881 stated, ' Our experience of these epidemics 
by no means supports an opinion commonly held that a summer diarrhoea 
makes its first fatal swoop upon the weakliest children.' While the alleged 
benefits to the community of this mortality are neither uniform nor un- 
doubted, the evil effects of infectious disease are very real, for it is a matter 
of common observation that the effect of these illnesses, especially in 
children, is to lower the vitality and reduce the physique sometimes even 

In endeavouring to trace the changes in mortality in England it will 
be noted that in early days all is expressed in vague terms, e.g. that in the 
days of the Black Death ' a fifth part of the men, women and children in 
all England were consigned to the grave ' ; ^^ occasionally a local chronicle 
records of certain years that the burials greatly outnumbered the chris- 
tenings, but definite information only begins with the London bills of 
mortality in late Tudor times. From them we learn that in the liberties 
of the City, within and without the walls during the great plague years, 
the mortality ranged from 200 to over 400 per 1,000 living, and that in 
healthy years, which were few, the rate was some 60 per 1,000. The 
subsequent history of London is one of steady fall of mortality, though the 
greatest change has occurred in our own lifetime. In the latter part of 
the seventeenth century the rate was 80 per 1,000 living, in the eighteenth 
century it was 50, by the middle of the nineteenth century it was only 
25, and since 1875 it has fallen rapidly to the present rate of 11-12 per 1,000. 
Some part of this change is due to variations in the age and sex constitution 
of the population at risk, but even when all corrections for this have been 
made, the mortality rate in England and Wales has fallen over a third 
since the beginning of registration in 1838. 

A great part of this reduction has been in the infant mortality, which 
is perhaps the most important from the standpoint of potential parenthood. 
This mortality in early years was very high : thus in 1754 the deaths in 
London of children under two years of age were 45 per cent, of the deaths 
at all ages. Since the period of registration the infant mortality oscillated 
around 160 per 1,000 until 1900, since when it has fallen to 60 per 1,000 in 
1923. The great part of the fall has been in deaths due to infectious 
diseases and diarrhoea ; there has been little or no change in the rates 
from congenital defects or developmental disorders, which have remained 
relatively unchanged in all classes of the community, so that this lethal 
selection against the naturally unfit remains as rigid as ever. The fail 
in the mortality rate has been ascribed to various features : cleaner milk, 
fewer flies, the disappearance of the old feeding-bottle, and it seems to 
be most certainly connected with increased skill in maternal care. Thus 

-•"^Ballard, Report of Local Qovernment Board, 1889, p. 43. 
'■■' Eitloghcm Histcriarum, Rolls ser.. No. 9, ITl., 2i;i 


it arises that tlie better spaced out the children are, the more survive. 
It is also significant that the change should have come about in the second 
generation of universal elementary education, suggesting the possibility 
that when the influence both of grandmother and mother is exerted in 
the direction of the sentiment for cleanliness inculcated in the school, the 
child reaps the benefit. 

The mortality in the early years of life is greater in the cities than in 
the small towns and in these than in the rural areas ; it is greater in the 
north than in the south for all classes of the community, but it must be 
noted that with the great fall in the present century the gap between urban 
and rural areas has been closing. This again suggests that education and 
a higher standard of personal hygiene are important factors, for the 
country is always more conservative in its actions and beliefs. In the same 
way, comparing the social classes, the death rate is lowest in the upper 
classes, particularly among the children of professional men, and the 
agriculturists, but highest among the unskilled workers and the miners. 
This indicates that the influence of custom as well as the direct effects of 
urbanisation may be factors to be considered. 

Special causes of morbidity are to be found in each of the main classes 
of workers. The mortality of the infants of agricultural labourers is 
below that of those of any other class of manual workers, not only as far 
as diarrhceal diseases are concerned — here, perhaps, they have better 
chances of obtaining fresh milk — but also from measles, tuberculosis and 
respiratory diseases generally. Some of the difference may be due to the 
rural child, on the average, being older than the townschild at the time 
he is attacked by infections ; for, whereas infantile infections spread 
through towns about every second year, in the country districts there may 
be an interval of five years between periods of epidemic prevalence. 
The infant mortality among textile workers is especially due to diarrhoea,'^" 
which may be ascribed in many instances to artificial feeding during the 
mother's absence at the mills. The children of this class also die notably 
from congenital malformation and prematurity, which might naturally 
have been attributed to the mothers working until a late stage of pregnancy, 
were it not that the mortality from these causes is even higher among the 
children of miners, whose women seldom work outside their own homes. 
The general infant mortality among the miners is higher even than among 
the unskilled and casual labourers in the towns, and if diarrhoea, gastritis 
and convulsions be taken together, their death rate from these causes is 
he highest of any class. In the Glamorganshire coal-fields the standardised 
child mortality in 1911 was 217 per 1,000 births for miners, and 176 for 
the rest of the workers in the area.^' This may be due to improper feeding, 
to insanitary conditions, or possibly expresses some difference in traditional 
methods of infant care ; though it should be noted that as the miners have 
the larger families there must be less individual attention available for 
each child. 

On the whole the evidence goes to show that morbidity, and especially 
infant morbidity, is closely associated with the aggregation of population; 

2« Various Annual Reports of Registrar-General, England and Wales, and especially 
Supplement to 75th Annual Report. 

2' Census of England and Wales, 1911, vol. xiii., pt. ii., table li. 


but that in recent years improved standards of social or individual hygiene 
and comfort have done much to neutralise specific causes of ill-health. 
It may also be taken as proven that such ill-health is the greatest cause 
of stunting of physique. As in the past the countryside has been freer 
from these morbid influences, the country-man has been the physical 
superior of the townsman, comparing class with class. 

There are three main ways in which the growth of towns and of the 
industrial system has prejudiced the health and thus the physique of 
the nation : adverse conditions of work which had little influence prior 
to the eighteenth century, unhygienic housing and bad feeding, which in 
varied ways have exerted their effects throughout a large part of human 
history. Some of these would be peculiar to the town, others would fall 
indifferently on town and country, and on all social classes save perhaps 
the very wealthiest, though even they could not entirely escape. The 
contrast is less vivid than would appear at first sight : the country child 
can get fresher food, it is true, but less of it perhaps, owing to the lower 
wages of his parents, though he often eats margarine, the butter being 
sold in the towns ; he gets fresher air outside but not indoors, since the 
country cottage may be as dark, ill-ventilated and overcrowded as any 
in a city court. 

The greatest change in the conditions of work was the rise of the 
factory, involving long confinement in monotonously ventilated rooms, 
as opposed to work in the open at the door of the home. Industrial 
centres may have been established in Roman times, but thence after for a 
thousand years and more they did not exist, and agriculture was the only 
important industry. The only factories were the local wind- or water-mills ; 
there were local industries in cloth, linen or metals, but the great centres 
of to-day were non-existent. 

The early factory was an extension of the home. Ure said : ' The 
workshop of the weaver was a rural cottage, from which when he was tired 
of sedentary labour he could sally forth into his little garden and with 
spade or hoe tend its culinary productions.' ^* Woollen weavers practised 
agriculture as a by-employment as late as the early part of the last 
century. The introduction of water- and steam-driven machinery 
aggregated the populations into the northern towns which arose near the 
sources of the power, and put a premium on the employment of children 
who could then do work which formerly required a man's strength. When 
local supplies ran short, children were procured from workhouses, even 
from as far off as London. Hunt, in his ' Political History of England,' ^^ 
says : ' From little more than infancy they laboured for long hours, thirteen 
or more a day, in rooms badly ventilated and injurious to health. They 
were half starved and cruelly punished. Such of them as survived the 
prolonged misery and torture of their early days, grew up more or less 
stunted and deformed men and women, physically unfit for parentage, 
morally debased, ignorant and brutalised by ill-treatment.' The mills 
were hotbeds of ' putrid ' fever, and the morbidity and mortality rates 
were appalling. In recent years the general hygiene of the worker, together 
with the removal of industrial risks, has made enormous strides, the result 
being apparent in the falling death rate and the healthier children. 

"^ Ure, Cotton Manufacture of Great Britain. 
-» Hunt, Political History of England, vol. x. 


So far as housing is concerned, in early days the English dwelt scattered 
through woods and marshes ; in mediseval times they began to flock to 
the towns in which the sanitary conditions were bad ; though regulations 
have existed even from Plantagenet days for the abatement of nuisances,^" 
e.g. the prohibition of the erection of pigsties in the streets of London. 
In the late mediseval period there were narrow streets with overhanging 
upper stories so that light rarely entered the lower apartments. ^^ Indoors, 
even in the great houses, the floors were covered with rushes piled, accord- 
ing to Erasmus, ^^ the new on the old for twenty years without clearance : 
an excellent breeding-ground for vermin. Sanitation was perhaps a 
little, but not much, better by Stuart times ; and, ' whatever sanitary 
gains may have accrued from the destruction of the City in the Fire, 
London in the late seventeenth century was an ill-conditioned place of 
residence, with hardly the rudiments of sewerage or water supply, and no 
systematic removal of refuse.' *^ In many years the burials outnumbered 
the bajitisms and the town fed on the country. In Hanoverian times 
matters, if anything, deteriorated owing to the most unhygienic window 
tax ; this, however, affected the country perhaps as much as the towns, 
for Howard ^* refers to ' farmhouses where the labourers are lodged in 
rooms that have no light or fresh air ; which may be a cause of our peasants 
not having the ruddy complexions one used to see so common thirty years 
ago.' During the industrial revolution the aggregation of houses and the 
pollution of the air greatly increased and produced their well-known evils, 
though the sanitation of the individual houses was, in some respects, no 
worse than before. London lost its evil pre-eminence in the matter of 
mortality which was transferred to the manufacturing towns of the north, 
in which diarrhoea attacked the infants, and fevers of all kinds their 
elders. In the late Victorian period conditions steadily improved, although 
in remoter districts matters change so slowly that some of the present-day 
crofters' huts in the Outer Hebrides closely resemble the habitations of 
neolithic man.^^ 

The third factor, food and its assimilation, is more closely associated 
with the foregoing than is usually realised. Leonard Hill ^^ has shown 
that sedentary occupations in still warm atmospheres have the effect 
of lowering the general metabolism and of reducing the desire for food, 
thus producing a similar effect to actual privation and affecting even the 
well-paid worker. Acting through long periods during the growing time 
of life, such factors whenever they arise may stunt growth as well as 
predispose to illness. McCarrison ^^ has indicated that the adult worker 
and even more the adolescent, need, no less than the growing child, a 
supply of food rich in vitamines, and balanced in its organic and inorganic 

^^ Memorials of London (H. T. Riley), p. 339, et seq. 

31 W. White, Phil. Trans., Ixxii., p. 35. 

''^ D. Erasmi Epistolae, lib. xxii., epist. 12, London, 1642. 

^^ John Simon, English Sanitary Institutions, p. 100. 

"* John Howard, State of the Prisons, p. 10. 

3^ Carnegie United Kingdom Trust. Report on The Physical Welfare of Mothers 
and Children, vol. iii., Scotland. Plates XIIL, XIV., and XV. 

3^ L. E. Hill, Medical Research Committee, Special Report Series, No. 32. 

^' Medical Research Committee. Special Report Series, No. 38 ; also B. Med. Jour., 
Feb. 21, 1920. 


components ; without tliis they hirk botlt vitality and re.sistanco. The 
foods required, eggs, butter, animal fats and fresh vegetables, are very 
expensive, but are not replaceable by the cheaper vegetable oils and lard. 
Many dietaries which appear satisfactory on a mere caloric basis prove 
failures owing to the lack of these vital elements. The industrial worker 
is doubly handicapped ; he not only loses his appetite and takes scarcely 
enough to provide the necessary energy for his work, but, too often, he 
takes even that in the form of margarines and canned foods which do not 
supply adequate vitamines. There is reason to think that the war-time 
rationing of foods and control of prices was to the benefit of the growing 
child of the elementary-school class in that it secured a more equable 
distribution of the essentials at a rate which was within the range of the 
family exchequer of a very large number. This helps to explain the un- 
doubted improvement of children's health and physique during a period 
in which disaster might confidently have been anticipated. If, as is 
probable, physique suffered with the concentration of the population in 
the industrial areas, no small part may have been played by the confine- 
ment in a rela.ving atmosphere and the substitution of inert for live foods. 
The worker who emigrates to more rural surroundings reverses these 
conditions and, if young enough, recovers part of his lost physique, and in 
any case his children, not being handicapped, fulfil their true potentialities. 
With feeding as with housing, though the industrial age brought its own 
defects, yet the contemporaneous increase of civilisation provided the 
remedy for some of the previous evils, such as those arising from imperfect 
methods of food preservation. 

Gilbert White wrote in 1778 ** : ' Three or four centuries ago before 
there were any enclosures, sown grasses, field turnips or carrots, or hay, 
all the cattle which had grown fat in summer and which were not killed for 
winter use were turned out soon after Michaelmas to shift for themselves 
through the dead months, so that no fresh meat could be had in winter or 
spring.' The curing at the best was very imperfect, and the diet of the 
poorer classes would be the semi-putrid sides of bacon, mutbon or beef. 
Indeed, it was enacted that such should be given to the outcast by the 
Scottish Parliament at Scone in 1380.^* ' Gif ony man brings to the 
market corrupt swine or salmond to be sauld, they sail be taken by the 
baillie and incontinent without any questions sail be sent to the lepper 
folke ; and gif there be no lepper folke, they sail be destroyed alluterlie.' 
Such continual winter sufferings must have worked harm, seeing that it 
was not a matter of an occasional meal but a steady regimen. No wonder 
an Aberdeen physician wrote of the effects : ' As we see dailie the pure 
man subject to sic calamitie nor the potent, quha are constrynitt be povertie 
to eitt evill and corrupte meittis, and diseis is contracit, heir of us callit 
pandemiall.' *" 

Toward the end of the eighteenth century the long-standing defects of 
food and housing were in full force, and their influence was accentuated 
by the coming of industrialism and the massing of people in towns. Thus 
disease from bad feeding and insanitary surroundings was the bane of 

'* Natural History of Selboriie. Letter to Barrington, Jan. 1778. 

" Acts of Robert III., Jiegiain Majejttatem, p. 414. Quoted by C'leighton, I.e., p. 1 13. 

*" (lilbert Skene, Treatise on Plague. Bannatyne Club ed., p. (i. 


(he metropolis and of the larger cities. Sir W. Fordyce *• could write : 
' I speak witliin the bounds of truth when I assert that, judging from the 
cases brought to my notice since 1750, there must be very near twenty 
thousand children in London, Westminster and the suburbs ill at this 
moment with the hectic fever, attended with tun bellies, swelled wrists 
or ankles or crooked limbs, owing to the impure air they breathe, the im- 
proper food on which they live, or the improper manner in which their 
fond parents bring them up.' Within our own memory disease such as 
is described by Fordyce has become unknown ; rickets in mild form still 
reduces stature, but severe deformities are rare in London and the South, 
though as yet to be found, albeit in lessened numbers, in the industrial 
cities of the North. The evils were checked in part by the various Factory 
and Public Health Acts and by improved sanitation which gxadually 
came into force, while other causes of malnutrition, such as late hours, 
lack of sleep, uncleanliness, and premature heavy work, have more recently 
given way before the force of the higher standard of civilisation and of 
personal well-being. 

Modern medical inspection and treatment are fast counteracting the 
chief causes depressing the health and physique of the children, and 
are also dealing with contributory secondary factors, such as defective 
teeth and other foci of chronic sepsis, verminous conditions and unsuitable 
clothing. No one who compares • jihotographs of present-day children 
with their predecessors of the seventies can doubt the change. It is 
significant that the town is now gaining over the country and that London 
children are now second to none. The treatment schemes did not come 
into force until just before the war, and affected almost exclusively children 
who did not reach military age in time to appear before recriuting boards, 
so that the benefits of the system could not be brought out in the Report 
of the Ministry of National Service. In this direction the future seems 

There remains the gap between the school and adult life. An expe- 
rienced Scottish recruiting board reported a falling off during adolescence 
both in the agricultural and the industrial classes.*^ In the former there 
are ' the evils of the bothy system, with its lack of home comforts, and the 
tendency to live on canned food ' ; in the latter ' the boy goes to the 
factory at fourteen, by sixteen he is earning full wages, indulging in all 
kinds of excesses, not having his due share of sleep and living on unwhole- 
some foods.' The young artisan, apprenticed to his trade, has far more 
favourable conditions ; ' he does not realise his full wage-earning capacity 
so early, his home is better, his social conditions more equable, he has not 
the same opportunities for excesses and lives a more physiological life.' 
The general impression of the recruiting reports was that the most critical 
period in determining the physical standard of manhood was the age 
from fourteen to eighteen. With any extension of facilities for appren- 
ticeship or trade instruction, with opportunities for the further treatment 
of ailments, even though these be of a voluntary character, much would 
be gained. Moreover — since the use made of these facilities would depend 

*i W. Fordyce, A new Enquiry into the Causes, Symptoms and Cure of Putrid 
and Inflammatory Fever, London, 1773, p. 207. 

*- Report, Ministry of National Service, vol. i., p. 138. 


on tlie mentality and character of the individual— the youth with the 
best mind and good will should gain the advantage and be favoured in 
his prospects of a successful marriage, through which lie could transmit 
these qualities to further generations. 

Turning to the genetic aspects of the subject, it is clear that the future 
of the nation depends on the interaction of two somewhat opposed pro- 
cesses, reproductive and lethal selection. Fecundity is a heritable trait, 
and parents who themselves are members of large families tend to produce 
many offspring who, in their turn, are similarly prolific. Lethal selection, 
on the other hand, counteracts this tendency in that the demands of a 
large family reduce the chances of the parents protecting themselves or 
their offspring, since the available care has to be distributed over a larger 
number. It will be noted that the shorter the intervals between successive 
births, the higher is the rate of infant and child mortality. 

The materials for any investigation into changes in density of poj^u- 
lation are very scanty until the decennial censuses can be consulted. 
While there are reasons to think the country was hy no means sparsely 
occupied in early days, there are no, even approximate, estimates until 
the fourteenth century, when the population of England and Wales is 
believed to have been about three million. There was a slow rise to six 
and a half at the middle of the eighteenth century, thence on a growth 
to nearly nine million at the first census of 1801, sixteen million in 1841, 
and twenty-six in 1881. After this the rate was retarded, and in 1921 
the population was approximately thirty-eight million. The period of 
rapid growth coincided with the industrial development of the early 
nineteenth century, the slowing down with the rise of competition from 

It is important to note that the increase of population was not uniformly 
distributed, either as to district, class, or occupation. In the earlier days 
the greatest density of population was, in the main, south of the line 
from the Severn to the Wash but extending up to Lincolnshire and the 
East Riding, and the predominant occupation was agriculture. A change 
began with the great development of pasture and the relative abandonment 
of arable land which reached its height in early Tudor times, when Hyth- 
loday could be represented in ' Utopia ' as saying : ' Your shepe that were 
wont to be so meke and tame and so small eaters, now, as I heare saye, 
be become so great devowerers and so wylde, that they eate up, and swallow 
downe the very men themselfes. They consume, destroye and devoure 
whole fieldes, bowses and cities.' *^ This process reduced the numbers, 
especially in the eastern counties and the southern midlands. Some two 
centuries later the rise of industrialism in northern areas adjacent to water 
l^ower and coal led to a great increase of numbers in marshy and moorland 
districts which had formed the refuge of a scanty and often pre-Nordic 

The areas of highest fertility to-day are the northern counties and 
Wales, while the lowest are found south of the line from the Severn to the 
Wash ** ; probably the difference is mainly due to social and industrial 
rather than to racial factors. The rural population is the more fertile ; 

*' Thomas More, Utopia, Bohn's ed., bk. i., p. 3S. 
** Cen-^nx of England and irafe, vol. xiii., pt. ii. 


even in cities tlic country-born have larger families than the true urban 
population. The higher rate of child mortality in the towns increases 
this difference, so that there is no part of England where the rural areas 
are not more effectively fertile than the small towns and these than the 
county boroughs. Their greater numbers, however, ensure that the urban 
population makes the bigger actual contribution to future generations. 
The rate of increase of the population is dependent upon the fertility, the 
age of marriage, the proportion of married individuals and the death rate, 
especially in early life. Of these there is no reason to suppose fecimdity 
as opposed to fertility has undergone any change, but the other factors 
have shown marked differences both from time to time and from one social 
class to another. 

Little seems to be known of the age of marriage or the extent to which 
any class remained celibate in early daj^s ; there were certainly restrictions 
on the marriage of serfs, while in the later mediaeval period the craft 
guilds opposed the marriage of apprentices, and until the nineteenth 
century subordinates in industries and handicrafts usually lived in and 
did not marry until they became master men. The less skilled workers 
soon attain to their maximum earning capacity and marry early, while 
the office worker and professional man has to wait to establish his position. 
The agricultural classes and skilled artisans also are noted to marry later 
than either the unskilled workers, the miners or the factory operatives. 

The census of England and Wales for 1911 *^ shows that the highest 
proportion of married men is to be found among the miners, who are 
followed at some little distance by the artisans and textile operatives ; 
while the agricultural labourers and the professional classes show the 
lowest marriage rate of all. The latter figures have a distinctly dysgenic 
significance which is accentuated by a consideration of the later age of 
marriage in these classes. Failure to mate is even more marked among 
the professional women than among the men and has steadily increased 
decade after decade. 

During recent years there has been a decline in fertility, a process 
which began in the higher classes, who have shown the phenomenon through- 
out the whole period in which registration data have been available. It 
is difficult to say what may have been the case in the past, but early 
genealogies usually record large families though relatively few survivors 
to maturity, so much so that the population was almost stationary between 
1700 and 1750. From the economic standpoint, Pearson,"* investigating 
the statistics of various parts of England, has suggested that the fall in 
the local birth rate became accentuated at certain dates which corre- 
sponded with local or general restrictions on the employment of children. 
Another view would ascribe the decline in fertility to a gradual subordi- 
nation of the sex instinct with the spread of culture and education. A 
comparison of the literature of different periods bears witness to a gradual 
disappearance of the idea that the only career for women was marriage, 
and that a girl should be reproached as an old maid at twenty. On this 
basis the decline would have spread from above downwards and would 
be delayed among certain classes. This factor involves both individual 

*^ Vol. xiii., pt. ii. 

"* K. Pearson, The Scope and Importance to the State of the Science of National 



and group j)sychoIogy since social traditions and class consciousness as 
well as personal passion are concerned, which hel])s to explain the lack of 
response to the appeals of the enthusiastic eugenist. 

That reduction in fertility has been of long standing is strikingly illus- 
trated by Cruin's *' study of tlie New England genealogies, in which he 
finds a progressive reduction in the size of the family and an increase in 
the proportion of childless marriages. 




size of 

of Childless 















The decline among the professional classes in Britain, even when varia- 
tions in age and length of marriage are allowed for, is a marked feature of 
the census of 1911. Of the other classes, minors, agricultural and other 
labourers have families above the average size, artisans are about the 
general average, while textile workers and other factory operatives have 
smaller families. The divergence between the different social classes was 
less marked in 1850 and reached a maximum in the nineties. 

The differential death rate, chiefly due to infant mortality, to some 
extent modifies the initial differences in fertility ; while the high fertility of 
the agriculturist is largely opposed by the low marriage rate and the relative 
infertility of the upper classes is exaggerated from the same cause. Both 
total and effective fertility are affected by female occupation, which tends 
to restrict the number of births, and also to increase the infant mortality 
owing to the absence of maternal care for a large part of the day. Siich 
occupations are most common in the case of wives of textile operatives, 
themselves accustomed to factory and mill life from a relatively early age, 
and among the wives of the labourers in the towns. 

The influence of differences in effective fertility in changing the distri- 
bution of the population among different social classes can be seen from 
a comparison of two tables, the first of which gives the percentage of each 
social class among the married couples, and the second the percentage of 
these classes among the surviving children from such parents.** 

Social Class 

Distribution per cent. 






Upper and Middle 






Skilled Artisan 



Mixed Occupations 



Unskilled Labourers 



Textile Trades 






Agricultural Labourers . 





*' Crum, Quarterly Journal, American Statistical As-iociation, 1914. 
■'*' Census of England an<l ^Val(■s 1911. 



This means, to take a concrete example, that the miners who form 
only 8-7 per cent, of the parent class provide 10-7 per cent, of the su^^^\-ing 
children. The imskilled labom-ers, the mining and the agricultural 
classes thus appear to be gaining at the expense of the upper and middle 
and the distributing classes. Mners and agriculturists are iisually of 
good physique, though from the mental standpoint the change is jaossibly 

There apjiears to be a general impression that the number of defective 
individuals, particularly of those suffering from mental defect, is greatly 
increasing. There is little evidence on this point of a comparable nature, 
but it may be definitely said that in London no such increase has taken 
place during the last fifteen years. The stocks from which defective 
individuals come are certainly often prolific, but the infant mortality is 
high. Indeed, so far as those individuals who are themselves mentally 
defective are concerned, the figures from institutions indicate death 
rates from ten to twenty times as great as those of the normal population. 
The figures regarding the defectives who have been kept under supervision 
in their own homes indicate rates far above the normal, though perhaps 
less than those in the institutions to which the worst cases naturally drift. 
Contrary also to popular belief mentally defective individuals do not mate 
in nearly as high a proportion as the normal. Out of some 360 defective 
girls who, while remaining outside an institution, have been under super- 
vision during the past ten years and who are of reproductive age, only 
eighteen have married and only seventeen have had illegitimate children, 
a figure which, if regrettably above zero, is not one to cause alarm. Of 
their children a large proportion appear up to the present to be of normal 
capacity. There is some reason for thinking that there is a great inter- 
marriage between defective stocks, and that the actual number of such 
stocks is in reality quite limited. 

The London school ser\'ice has collected information as to the size of 
the families one member of which has come to notice on account of mental 
deficiency. The figure will naturally appear higher than one derived 
from the census returns, since no knowledge exists concerning childless 
families of the same stocks or of families in which all the children had died. 
The figures are corrected to show only completed families which have been 
taken as those where the mother, at the time of the inqiiiry, had died or 
had attained the age of forty-five, and, for purposes of comparison, similar 
figures are given for the families of children who had obtained scholarships. 

No. of 

No. of 

No. of 




of Mother 


Imbeciles and Idiots 




Children at Schools for the mentally 

defective ..... 




Scholarship holders 




As the differential death rate continues to act there is reason to think that 
the defective stock are the less effectively fertile by the time the reproduc- 
tive age is reached. If it be remembered that the factors act still more 
severely against those themselves actually defective, the reason why the 
defective has not overrun the country is evident. Experience in any 


children's hospital or infant welfare centre reveals the handicap against 
the children of the mentally inferior parent. 

There remains one important factor bearing on physique — namely, 
emigration. Since the early part of the seventeenth century the British 
Isles have sent abroad large numbers of the most efficient of their people, 
agriculturists and skilled workers of all kinds possessed of just the qualities 
which the nation demands for its own physical good. Where these 
have come from somewhat isolated areas the result has been a steady loss 
of the best, with the consequent replacement in the next generation by the 
offspring of an undue proportion of the next best. This clearly has a 
dysgenic effect, and it is often stated that this is the cause of the inferior 
calibre of the inhabitants of some remote hamlets. This — probably the 
most serious drain to which the nation has been, and still is, exposed — 
can only be regarded with equanimity on the ground that England's loss 
is the gain of the daughter nations. The emigrants have been largely of 
' Nordic ' and ' Prospector ' stocks, seeking a wider scope for their energies, 
and the result will in the end seriously modify the racial composition of 
some parts of the British Isles, particularly Scotland. So far as there 
has been any difference between rural and urban areas it is distinctly 
the former that have supplied the higher proportion of emigrants. Emi- 
gration, indeed, in recent years has been a serious factor in rural 

Summarising the whole survey I would submit that a pessimistic view 
of the physical or mental condition of the people of England is unnecessary 
and unfoimded. Stature and weight at least are not less than in the days 
of the ' Making of England,' of Agincourt or of Waterloo. The great war 
showed the possession of powers of resistance to physical adversity that 
have never been equalled, and under a test applied to a proportion of 
the nation never before a})proached, while the versatility of inventive 
powers was demonstrated everywhere. So far as the children are con- 
cerned, education is more general and the ladder wider and more used 
than at any period in our history. The general health of the nation is 
better and the expectation of life longer than ever before. There are no 
grounds for thinking the physical conditions of any class are worse than 
that of corresponding classes at previous epochs, even among those persons 
and classes on whom the adverse conditions of life associated with urbanisa- 
tion and industrialism have pressed hardest and have been least opposed. 
The real increase of the unfit is much less than has been assumed from 
a priori axguments. Reproductive selection which has a tendency to 
increase the apparently less valuable stocks is opposed by a lethal selection 
which has not been abolished, while emigration from the eugenic standpoint, 
though a real disadvantage to England, has been a source of strength to 
the Empire of Associated Nations. The dysgenic tendencies of industrial- 
ism are being successfully opposed by the higher level of general culture 
and the awakening of a national conscience, but more especially by the 
more intelligent care for the children of the nation, in which the application 
of preventive medicine to education is playing no mean part. The 
Education Acts, if they have not revealed every child as a potential 
university scholar, have proved the best of Public Health measures ; 
while all available evidence points to the intellectual average being equal 
to that of any other country. Civilisation may be making greater demands 
1924 P 


ou .'its bearers, but tlieir qualities are neither diminishing nor deteriorating 
and more and more are fitted to shoulder the burden. 

A younger country in developing its industries can profit by the expe- 
rience of the older and secure from the start better hygiene and a more 
effective education, can watch over its most favourable racial elements, 
establish a public opinion favourable to the early segregation of degenerate 
types, and, as Canada is doing, can limit immigration to those fit to become 
citizens of the great Dominion. 

Periodical surveys are necessary to check the changes in the population. 
Failing more extensive measures these may be effected through the 
records of the medical inspection of school children, though in these 
anthropometric data are but scanty. Toronto has long been known for 
its standard survey, and it is to be hoped that similar data will be collected 
in all parts of the Dominion. The matter is of great importance, since 
it is only on the basis of careful physical and mental surveys that legislation 
directed, towards social and racial hygiene could properly be introduced 
and rightly justified. The lack of such information has been a great 
handicap to the discussion of such measures in Britain, and has allowed 
a freer play to pessimistic \dews. 

None the less, despite all forebodings, it may confidently be stated 
that the Mother Nation has remained true to herself and deserves now, as 
of yore, the encomiums of the " Polychronicon ' ■"" : 'Engelond ful of pley, 
fremen well worthy to pley, fre men, fre tonges, hert fre, fre helth al the 

■''■' R. Higden, Polychronicon, Trevisa's trans., vol. ii , p. 19. 




H. H. DALE, C.B.E., M.D., F.R.S., 



In the mind of every physiologist visiting Toronto to-day one recent 
advance in our science will certainly be uppermost. We rejoice with our 
colleagues here in a great achievement which has opened new vistas of 
knowledge to exploration, has brought relief to unmeasured misery, and 
has turned the eyes of a world, too often careless of such things, in proper 
gratitude and well-founded hope to this University and its Medical School. 
Insulin, and its still marvellous and mysterious action, have held a promi- 
nent place in the interest of many of us, myself included, during the past 
year or two. In one of our meetings, however, we shall have the opportunity 
of considering the observations and opinions of many who are now working 
on its properties and their significance, and among them will be some who 
were associated with its discovery. I have thought it appropriate, there- 
fore, to ask your attention to-day to some recent developments in a widely 
different field of investigation. The subject which I have chosen presents 
points of general 4)hysiological and biochemical interest, apart from its 
immediately practical importance for the treatment of disease. It has, 
further, in one way, a special appropriateness to this year's meeting of the 
British Association. For our knowledge of an important group of diseases, 
caused by the parasitic trypanosomes, which have provided the experi- 
mental material for a very large proportion of chemotherapeutic investi- 
gations, we are in the largest measure indebted to the pioneer work of the 
distinguished President of the Association, Sir David Bruce. 

I. The Theoretical Origin of Chemotherapy. 

Chemotherapy may be defined as the specific treatment of infections 
by artificial remedies. The object of those who study it is to find new 
remedies which will cure or arrest diseases due to infections, not by 
alleviating the symptoms or invigorating the patient, but by directly and 
specifically suppressing the infection. Chemotherapy, in this wide sense, 
is not entirely of recent growth. When the natives of Peru discovered the 
value in fevers of the cinchona bark, which the Jesuits brought to Europe 
in the 17th century, they had found a specific remedy for malaria, which 
is still the best available. Similarly the natives of Brazil had found in 
ipecacuanha, which reached Europe shortly after cinchona, a remedy for 
amoebic dysentery better than any other which our modern systematic 



and scientific efforts have produced. Modern Chemistry, indeed, has 
separated the alkaloids from these drugs, and has made it possible to 
identify among them the actively therapeutic constituents ; Protozoology 
has revealed the nature of the infections. We know now that cinchona owes 
its curative action chiefly to quinine and quinidine, and that they act as 
specific exterminators of the malaria parasites, and not simply as remedies 
for fevers in general ; and we know that ipecacuanha owes its action to 
emetine and cephaeline, and that these act as exterminators of the enta- 
moeba causing tropical dysentery, and not simply as symptomatic remedies 
for dysenteries of any kind. But chemistry has produced no better remedy 
for malaria than quinine, or for amoebic dysentery than emetine ; and 
the method by which either of these alkaloids cuts short the infection by 
a particular parasite, the nature of its specific action, remains a fascinating 

The modern development of chemotherapy, as a new department in 
therapeutic science, claiming the co-operation of parasitologists, micro- 
biologists, and synthetic chemists, did not take origin, however, simply 
from the study of these traditional remedies. It may be regarded rather as 
an outcome of the study of the natural antibodies. The investigation of these 
natural antagonists to infection produced a new therapeutic ideal. Not 
only had they shown themselves to have an intensely specific affinity for 
the infecting organism of the toxin which caused their production ; they 
were also perfectly harmless to the patient, behaving, in relation to his 
organism, as normal constituents of his body fluids and tissues. Ehrlich 
aptly compared them to magic bullets, constrained by a charm to fly 
straight to their specific objective, and to turn aside from anything else 
in their path. 

Of the artificial remedies, on the other hand, which man had empirically 
discovered, even of drugs like those just mentioned as being specific for 
certain infections, the best that could be hoped was that they would 
eliminate the parasite before they poisoned the patient.* And thus, when 
the limitations of natural immunity were becoming clearer; when it was 
realised that to certain forms of infection, several of which had proved to be 
infections by protozoa, the body was unable to produce antibodies of 
sufficient potency to eliminate the infection and leave the patient immune ; 
the question arose whether, with the new and growing powers afforded by 
synthetic chemistry, man could not so far rival Nature's achievements as 
to produce, in the laboratory, substances specifically adapted to unite with 
and kill the protoplasm of these parasites, as the natural antibodies united 
with that of others, and to leave the tissues of the patient similarly un- 
affected. The ideal of this new and systematic Chemotherapy, as the 
imaginative genius of Paul Ehrlich conceived it, was to be the production 
by synthesis of substances with a powerful specific affinity for, and a 
consequent toxic action on, the protoplasm of the parasites, and none for 
that of the host — of substances, to use Ehrlich's own terminology, which 
should be maximally parasitotropic and minimal^ organotropic. 

I want to invite your attention to-day to the results which, during the 
last twenty years, have been produced under the stimulus of this bold 
conception ; not, indeed, to attempt a survey or summary of all that has 
been done, but, in the light of a few of the suggestive facts which have 
emerged, to consider how far this hypothesis has justified itself, and whether 

I.— PHYSIOLOGY. 2 1 3 

it can be accepted as a safe guide to future progress, as it has undoubtedly 
provided the initiative and working basis for much of what has been 
accomplished hitherto. Before we deal with some of the actual results 
obtained, it may be well to consider a little more closely what Ehrlich's 
working hypothesis involved. The problem was to discover, by chemical 
synthesis, a compound which, in virtue of its chemical structure, should 
have a maximal affinity for the protoplasm of a microscopic parasite, such 
as a trypanosome, and a minimal affinity for that of the host's body cells. 
These affinities were pictured by Ehrlich, in the terms of his side-chain 
theory, as determined by certain side-chains of the complex jarotein mole- 
cule, or chemoreceptors, which endowed the protoplasm with specific 
combining properties. When it is remembered that knowledge of the 
chemistry of the protoplasm of a trypanosome is almost nil, and that what 
little we do know suggests that it is very similar to that of our own cells, 
it will be admitted that the enterprise was one calling for scientific courage 
and imagination in the highest degree. Complete failure would not have 
been surprising ; the matter for surprise, and for admiration, is that so 
large a measure of practical success should, at the end of two decades, 
already claim record. 

n. Trypanosomes and Spirochsets. 

i. The Action of Dyes and Analogous Compounds. 

The investigations leading, in the last few j^ears, to a clear promise, 
at last, of the successful treatment of the diseases in man and animals 
due to infections with trypanosomes, had at least two different starting- 
points, the action of dyes and the action of arsenic. Ehrlich's early interest 
in the synthetic dyes, and his observations of the curiously selective distri- 
bution which they often exhibited among the cells and tissues of the body, 
naturally suggested the possibility of finding, in this group, a substance 
which would selectively fix itself to the parasite and poison its protoplasm, 
without injuring that of the host. The technique developed by Laveran 
and Mesnil, by which a particular strain of trypanosomes could be passed 
through a series of mice or rats, and produce an infection of standardised 
type and virulence, enabled the efiect of a large selection of dyes to be 
investigated, with the view of finding one which would favourably influence 
the infection. A starting-point having been obtained, the resources of 
synthetic dye production were available to produce an indefinitely long 
series of derivatives and modifications of the active compound, each to 
be tested in its turn. In this way Ehrlich and Shiga arrived at a substance 
which gave experimental promise of curative value, a benzidine dye to 
which the name ' Trypan red ' was given. 



NH., HjN 

NaO,S ly A y' SOjNa NaOjS 

Trypan reel. 



Two years later, Mesuil and Nicolle, proceeding further along the same path, 
described an evon more favourably active blue toluidine dye, ' Trypan blue.' 

N— ^ 


CH3 NaOjS 


Trypan blue. 

This is the only one of the dyes which has hitherto had a genuine practical 
success in the treatment of a protozoal infection, not indeed by a 
trypanosome, but by an intracorpuscular parasite of the genus Piroplasma, 
which infects dogs and cattle. This successful application of Trypan blue 
to an animal disease has a special interest for us to-day, in that it resulted 
from the joint labours of last year's President of this Section, Professor 
Nuttall, with a Canadian collaborator, Dr. Hadwen. 

We may turn aside at this point to inquire how far the results even of 
these earlier investigations corresponded with the theory which gave them 
their impetus. Did these dyes really act by selectively staining and killing 
the parasites, and leaving the host's cells untouched ? The evidence was 
certainly not in favour of such a view. Ehrlich and Shiga themselves 
observed that Trypan red, even in relatively high concentrations, was 
practically innocuous to the trypanosomes outside the body. The trypano- 
somes, like other cells, were not stained by the dye until they died, and 
there was no clear evidence that they died sooner in the Trypan-red solution 
than in ordinary saline. Again, Trypan red cured an infection by the 
trypanosome of ' Mai de Caderas' (T. equinum) in the mouse, but not the 
same infection transferred to the guinea-pig, rat, or dog ; nor did it cure 
an infection with the trypanosome of Nagana (T. hrucei) in mice. Now, 
to explain such a difference by stating that the affinity of Trypan red for 
T. equinum was much higher than its affinity for the tissues of the 
mouse, but not than its affinity for those of the rat, would be merely 
to restate, in terms of the theory, the observed fact that the mouse was 
cured while the rat was not ; and the lack of direct affinity for the dye 
shown by trypanosomes outside the body made such an interpretation 
in any case unsatisfactory. One point, however, appeared very significant, 
and it is met repeatedly in studying the action of effectively chemothera- 
peutic substances, namely, that the trypanosomes treated with the dye 
in vitro, though neither obviously stained nor visibly harmed, had lost 
their power of infection, and died out promptly if introduced into the body 
of a mouse. Under such conditions only minimal traces of the dye are 
introduced into the animal, and we are left with a series of alternative 
possibilities. It is possible that sufficient dye has been taken up by the 
trypanosomes to kill them eventually, the period of survival in vitro being 
inadequate to display its action; or that Trypan red is converted by the 


influence of the body fluids and tissues into sonictliing which is effectively 
lethal for tiie parasite ; or, again, that the effect of the thug is not directly 
to kill the trypanosonies, but, leaving their individual vitality and motility 
unimpaired, so to modify them that they have lost the power of rapidly 
reproducing themselves and invading the fluids and tissues of the mouse's 
body — in other words, have lost that complex of adjustments to the various 
factors of the host's natural resistance which we crudely summarise as 
' virulence.' Such possibilities involve either storage or modification of 
the dye by the host's tissues, or their essential co-operation in its curative 

One other active dye must be mentioned as providing the link with a 
recent, most important advance. Mesnil and Nicolle in 1906 made some 
promising experiments with a dye, Afridol violet, which differed from any 
previously tested, in that its central nucleus was diamino-diphenyl-urea. 

-NH— CO— NH- 

OH NH., 

NaO,S '.^ A / SO,Na 
Afridol violet. 

From this time onwards there was no further public indication of progress 
along these lines until 1920, when Handel and Joetten published the results 
obtained with a remarkable substance which, as the result of some fifteen 
years of continuous work by their scientific staff", had been introduced by 
the great dye and chemical firm of Bayer. This substance, which is not a 
dye, but the colourless, water-soluble salt of a complex sulphonic acid, has 
hitherto been known as Bayer ' 205,' and, for reasons which need not con- 
cern us, the firm decided not to publish its formula. To students of their 
patent specifications, however, it seemed pretty certain that it would 
prove to be one of a long series of compounds, formed of chains of amino- 
benzoyl radicles, united by amide linkages, with a central urea linkage, 
like the dye last mentioned, and terminal naphthylamine sulphonic acid 
groupings." A number of these substances, having no diazo-linkages, 
were not dyes, but there was no indication as to which constitution, out 
of an immense number possible, would prove to be that of the remarkable 
substance numbered ' 205.' There is a reasonable probabiUty that its iden- 
tity has now been settled by the recent work of Fourneau and his co-workers 
in the Pasteur Institute, who made and investigated an extensive series of 
compounds of this general type, and found one, which they numbered 
' 309,' which conspicuously excelled all others, even those closely related 
to it, in the favourable ratio which it displayed, between a just toxic dose 
and that which caused a trypanosome infection in mice to disappear. 
As in the case of ' 205,' the ratio, the ' chemotherapeutic index ' of Ehrlich, 
was found by Fourneau, in some experiments with his compounds, to 


be well over 100. At least it may be said that, if M. Fourneau has not 
identified Bayer ' 205,' he has discovered another compound having very 
similar, and probably as valuable, properties. 

NaSOa NH— C0< > • CH3 CH, . < >C0 - NH SO^Na 


NH— CO— NH. 
Foumeau's ' 309 ' (possibly identical with Bayer ' 205 '). 

The most remarkable property of ' 205 ' is the long persistence of its 
effect. A dose injected into a mouse, a rabbit, or a rat will not only free 
til e animal, if already infected, from trypanosomes in a few days, but will 
also render it resistant to such infection for a period of weeks or even 
months. During that period its serum, or extracts from certain of its 
organs, exhibit a curative action if injected into another animal infected 
with trypanosomes. 

Though there seems no reason to doubt that this substance has cured 
a number of cases of African sleeping-sickness in man, even some in which 
the disease was well advanced and in which all previously known remedies 
had failed, the mode of its action still presents a number of attractive 
obscurities. Like many other remedies which are experimentally efficient 
when injected into the infected animal, it has little or no obvious action 
when directly applied to trypanosomes in vitro. The paradox is, perhaps, 
less than usually significant in this case, since the action in the animal is 
delayed, a period of a few days elapsing before the trypanosomes begin to 
disappear from the blood. We might suppose that the action is too slow 
to be recognised during the period of survival of the parasites outside the 
body, or that it affects not the individual vitality of the trypanosomes, 
biit their power of reproducing themselves. The latter idea is supported, 
as in other cases, by the fact that trypanosomes treated with the drug 
in vitro, or taken from an injected animal before the curative effect has 
become manifest, fail to infect another animal. It is contradicted, how- 
ever, by the observation that the trypanosomes, just before the curative 
action begins, show not a depression, but a stimulation of reproductive 
activity, division forms becoming abnormally common. Is it that during 
or immediately after division the parasites become specially liable to the 
action of the drug ? It may be so ; but one thing seems perfectly clear, 
namely, that the action is a very complex one, involving the co-operation, 
in some way, of the host. For here again it is found that the curative 
action, on infections by the same strain of trypanosomes, varies enormously 
with the species infected, a mouse being cured with ease, an ox or a horse 
with difficulty or not at all. A curious fact is that the rapidly progressive 
and fatal infections produced in mice by certain pathogenic trypanosomes 
are easily and certainly cured, while the apparently harmless natural 
infection, seen in many wild rats, by T. letvisi is not aft'ected at all. Then 

T.— rHYSIOLOGV. 217 

there are some curious records of treatment in man, in which the symptoms 
of sleeping-sickness have disappeared, but the trypanosomes are still 
found in the cerebro-spinal fluid, suggesting that, though the parasites 
have not been killed, they have lost their virulence and their power of 
invading the brain substance. 

The features of the action of this remedy, however, which have most 
interest for the physiologist and the biochemist are those related to the 
long persistence of its effect. ' 205 ' has a large molecule, but it is extremely 
soluble in water, and diffusible through collodion membranes. How, in 
such circumstances, can we explain the persistence of its sterilising and 
prophylactic action for months after an injection ? At first sight one is 
tempted to regard it as incredible that a substance with these properties 
should persist in the body for such a period, and to suggest that the action 
must be due to its stimulation of the body to form its own protective sub- 
stances. This possibility, however, seems to be excluded by the fact that 
the serum of the protected animal does not lose its curative properties if 
heated. On the other hand, there have recently appeared, some of them 
only in preliminary abstract, a series of highly suggestive observations, 
indicating that ' 205 ' has properties of entering into a combination of 
some kind with the serum proteins. After standing for an hour or two 
in serum, ' 205' no longer passes into an ultra-filtrate through collodion, 
and if the proteins are coagulated by heat is not to be found in the filtrate. 
The proteins of the blood, moreover, are stated to lose many of their charac- 
teristic properties by entering into this combination, the blood losing its 
normal power of clotting, and the serum proteins not being precipitated 
by mercury salts or tannin. 

It would be both useless and presumptuous for a mere onlooker to 
speculate in detail on the significance, for the curative action of ' 205,' of 
properties which are only now beginning to be investigated. One conclusion, 
however, I think we are entitled to draw. It is sufficiently evident that 
here is no question of a substance curing simply on account of its 
affinity for parasites and lack of affinity for the host's tissues. What direct 
action on the parasite ' 205 ' itself may possess has still to be demon- 
strated ; we may feel reasonably certain, on the other hand, that its 
affinities for the constituents of the host's blood and tissues play an 
important part in its remarkable and peculiar curative properties. 

ii. Derivatives op Arsenic. 

In the case of the other series of investigations which I mentioned, that 
dealing with the organic derivatives of arsenic, we find again many 
difficulties, in the way of the simple theory, of a cure due to distribution by 
chemical affinities. None of the compounds of this series, which have 
reached practical trial and success in the treatment of spirochsetal or 
trypanosomal infections, atoxyl, salvarsan, or tryparsamide, has a 
directly lethal action on the parasites in dilutions at all comparable to 
those which can be safely and effectively produced in the body of the host. 
The paradox of this direct inertness of atoxyl, the starting-point of the 
series, seemed to be explained when Ehrlich showed that its reduction to 
the corresponding arsenoxide produced a substance with an intense 



tlirectly lethal action ou trypauosomes. Similarly the partial oxidation of 
salvarsan, to the corresponding arsenoxide, produced a substance having 





Arsenoxide from • Atoxyl.' 

the intensely lethal action on spirochsets or trypauosomes in vitro, which 
salvarsan itself conspicuously and paradoxically lacked. In these cases, 
we may make the supposition, which Voegtlin and his co-workers, espe- 
cially, have recently supported by detailed evidence, that the reduction or 






' Salvarsan. ' 

NH., HCl 



Arsenoxide from 'Salvarsan.' 

oxidation efiected by contact with the tissues is the essential preliminarj'^ 
to the curative action ; a supposition which, it will be noted, again intro- 
duces the host as an essential participant in the cure. The fact, that the 
administration of these relatively inactive predecessors is therapeutically 
more effective than the injection of the directly active oxides derived from 
them, would then be explained on the assumption that the slow liberation 
of these latter in the body, at a rate which never produces a high concen- 
tration, provides the optimum condition for their persistent action on the 
parasites, without danger to the host. This slow and persistent liberation 
of the directly active substance would be favoured by the physical proper- 
ties of salvarsan, which at the reaction of the body is practically insoluble, 
and must be rapidly deposited after injection. 

In their recent work on the action of Tryparsamide, the compound, 





CH2 CO NH.2 

prepared by Jacobs and Heidelberger at the Rockefeller Institute, which 
has shared with Bayer ' 205 ' the credit of making the eventual conquest 


(jf African sleeping-sickuess a hopeful possibility, Brown and Pearce tind 
it necessary to introduce yet other considerations to explain its effects. 
Tested by Ehrlich's therapeutic index — the ratio between the lowest 
curative and the highest non-toxic dose — it gives a relatively unfavourable 
figure. Brown and Pearce practically abandon the attempt to accoiint for 
its action on the supposition that it directly kills the parasites, and attri- 
bute its value largely to its power of penetrating easily into the tissues and 
reinforcing there the processes of natural resistance. 

iii. Action of Bismuth. 

Another conception of the mode of action of these arsenical remedies, 
also involving a direct participation in the host's tissues, was put forward 
by Levaditi. He found that from atoxyl a directly parasiticidal prepara- 
tion could be obtained, by incubating it with an emulsion of fresh liver 
substance. As the first step, therefore, in the curative action of atoxyl, 
he postulated a combination of its reduction product with some constituent 
of the liver or other tissue, giving rise to the essential curative complex, 
which he named ' trypanotoxyl.' Levaditi's observations were explained 
by Ehrlich and Roehl as due simply to the reducing action of the liver 
substance on atoxyl ; but it would be difficidt to apply this explanation to 
the quite recently published observations by Levaditi and his colleagues, 
on the mode of action of bismuth in curing spirochsetal infections. A 
sodium potassium bismuthyl tartrate — a bismuth analogue of tartar 
emetic — had been found to have valuable curative properties in syphilis 
and other spirochsetal infections. Later, various other bismuth salts, 
bismuth suboxide, and even finely divided metallic bismuth, were found 
to produce similar effects. According to Levaditi and Nicolau, these 
preparations have, by themselves, a relatively weak action, or none at all, 
on the spirochsets outside the body. If they are mixed, however, with a 
cell-free extract of liver, which is itself harmless to spirochsetSjthe mixture, 
after incubation, acquires a potent spirochseticidal action. The possibility 
of a mere reducing action of the liver extract seems here to be excluded, 
since bismuthous oxide, or metallic bismuth itself, yields a spirochiieticidal 
mixture, containing Levaditi's hypothetical ' bismoxyl,' when incubated 
with the liver extract. If these observations are confirmed, there will be a 
strong indication that some cell-constituent enters into the composition of, 
or is essential to the formation of, the directly active substance from any 
of the derivatives of arsenic, antimony, or bismuth, as a preliminary to its 
action on an infection due to a trypanosome or a sjjirochset. Again we have 
evidence of an organotropic property of the remedy, as an essential 
condition of its activity. 

iv. Resistant Strains of Trypanosomes. 

In the phenomena of the acquisition of resistance, by a strain of infect- 
ing trypanosomes to a particular curative drug, discovered and largely 
worked out in Ehrlich's laboratory, we meet again with facts which can 
only with the greatest difficulty be reconciled with the assumption that 
the drug directly attacks the parasites. It was found, for example, that 
if a mouse infected with trypanosomes received an incompletely effective 
series of doses of atoxyl, the trypanosomes appearing in the blood at each 
relapse were more and more resistant to the drug, until they could not 


be caused to disappear by any dose of atoxyl which the mouse would 
tolerate. The strain, having once acquired this resistance, would retain it, 
on passage through an indefinitely long series of mice, without further 
treatment. Mesnil and Brimont, however, made the remarkable observa- 
tion that, if the strain of trypanosomes was transferred to a rat, it imme- 
diately became in that animal susceptible again to treatment with atoxyl, 
remained so as long as it was kept in rats, to reacquire its old resistance 
to atoxyl as soon as it was re-transferred to mice. Such a fact seems to 
be not at all exjslicable on the theory that the directly active agent, to 
which the trypanosome becomes resistant, is a mere reduction product 
of atoxyl ; it is much more easily reconciled with a mechanism such as 
that described by Levaditi, in which a constituent of thehost'stissues enters 
into the formation of the trypanocidal substance. We can imagine 
the trypanosome becoming immune to Levaditi's mouse-trypanotoxyl, 
and remaining susceptible to the corresponding rat-product. 

The whole question of this acquired resistance of the parasites to the 
action of curative drugs bristles with points of difficulty and interest. 
Ehrlich attributed the sensitiveness of the parasite, for a particular curative 
agent, to the possession by its protoplasmic molecule of a special form of 
side chain, or ' chemoreceptor,' which determined its affinity for that agent. 
When the trypanosome became resistant, it was simple to suppose that it 
did so by losing the appropriate chemoreceptors ; an atoxyl-resistant 
trypanosome, for example, had lost its atoxyl receptors. Apart from the 
objections already mentioned, this conception met a new difficulty, when 
in Ehrlich's laboratory it was found that the resistance was by no means 
as rigidly specific as it had first appeared to be. Not only imperfect 
treatment with atoxyl, but trCjatment with a particular group of dyes, having 
no kind of chemical relation to it, was found to produce a race of trypano- 
somes resistant to atoxyl and to other arsenical derivatives. To suggest 
that the chemoreceptors for arsenic and for these dyes are identical is 
merely to restate the fact of this reciprocal action in terms having no defi- 
nite meaning. Obviously no more precise conception as to its significance 
can be formed until we know something more of the conditions on which 
resistance and susceptibiHty depend. A recent suggestion by Voegthn 
has interest in making, at least, an attempt at interpretation in more 
definite biochemical terms. Voegtlin and his co-workers point out that 
arsenious oxide and its derivatives readily combine with substances con- 
taining a sulphydrile grouping, and find that the toxic action of the organic 
arsenoxides, on trypanosome and mammal alike, is depressed by the 
simultaneous injection of excess of various sulphydrile compounds. 


RAs = 0-f^g;j^ = ^-K +H.0. 


III. Suggested Reaction of an Arsenoxide with a Sulphydrile 


The work of Hopkins, showing the importance of one such sulphydrile 
compound, reduced glutathione, in the hydrolytic oxidation-reduction 
processes of the cell, suggests to Voegthn that a combination with such 
groups, and consequent suppression of this vital function, may explain 


the toxic and curative actions of the arsenical derivatives, and that a 
formation by the trypanosome of the sulphydrile compound, iu excess of 
its vital need, may be the basis of acquired resistance. If certain dyes 
similarly affect this cellular oxidation system, the production under their 
influence of strains of tryj^anosomes resistant to arsenic would also be 
explained. So stated the suggestion leaves many aspects of the problem 
still unconsidered ; but it may at least be allowed the merit of an attempt 
to interpret the action of these drugs in terms of known biochemical facts. 

IV. Emetine and Dysentery. 

To turn to another example of a chemotherapeutic problem, I may 
mention briefly some results obtained, some years ago, by Mr. Clifford 
Dobell and myself, in an attempt to explore the curative action of emetine 
and the other alkaloids of ipecacuanha in amoebic dysentery, with a view 
to finding a more effective treatment. At the time when we took up the 
problem it seemed simple. Rogers had recorded that the amoebae obtained 
from a case of amoebic dysentery, and treated in vitro with emetine, were 
rapidly killed by the alkaloid in dilutions as high as one part in 100,000. 
This seemed to explain the action of emetine as a simple and direct one on 
the parasites, and to provide a rapid method for testing a series of com- 
pounds for their therapeutic possibilities. We failed, however, as other 
observers before and since have done, to confirm the observation ; on the 
contrary, we found that the dysenteric amoeba?, obtained from cats 
secondarily infected, or, in a control observation, directly from man, were 
surprisingly insusceptible to the action of emetine, living for hours in 
concentrations much greater than the highest which they would tolerate 
of other alkaloids, which had no curative action in dysentery. One of 
the other natural alkaloids of ipecacuanha, methyl-psychotrine, and certain 
artificial derivatives of emetine, were much more effective in killing the 
amoebae in the test tube, and at the same time were practically devoid of 
the characteristic toxicity of emetine and cephaeline for mammals and for 
man. Here, on the classical assumption of chemotherap}'-, should have 
been ideal remedies for amoebic infection — substances much more parasi- 
totropic and much less organotropic than those already known to be effec- 
tive. Yet each of them in turn, when administered to patients suffering 
from amoebic dysentery, in doses much larger than those in which emetine 
could be tolerated, produced no effect whatever on the dysentery, which 
promptly cleared up when emetine was subsequently given. Among the 
members of this group of alkaloids which were tried, the curative effect 
seemed to be proportional rather to their toxic and nauseating action on 
the patient, than to their lethal action on the isolated amoebae. Yet 
emetine and cephaeline are not mere symptomatic remedies ; they definitely 
stop the progress of infection by the amoebae, and, properly administered, 
eliminate them altogether from the body. 

Yet another puzzling observation, made by Dobeil and myself, was 
that an amoebic infection which readily yielded to treatment with emetine 
in man, was entirely uninfluenced by emetine when transferred to the cat. 
In no way is it possible to account for these facts without admitting a co- 
operation of the patient's tissues in the curative action ; nor, with that 
admission, can we do more than consider possibilities. We only know that 


the truly parasitic Entamceha histolytica, which cannot live without invading 
the tissues, can be checked in this invasion and eliminated from the body 
by administering emetine, while other Entamoebse, which live on faecal 
debris, remain unharmed. Whether the tissues are so altered that the 
amcBbse cannot invade them, or the amoebae, without being directly killed, 
are so weakened in virulence that they cannot invade the tissue and obtain 
their food, but succumb in face of the normal resisting powers of the host, 
are possibilities on which we can only speculate, and no method of bringing 
them to the test of experiment has yet been found. 

The work of Morgenroth and his co-workers, extending now over more 
than a decade, has again led them to emphasise, in connection with the 
curative action of substances which they have examined, a fixation to the 
cells and tissues of the host, a definitely organotropic property, as an 
important factor in the effect. Two examples may be mentioned. 

V. Quinine and Malaria. 

One of the earliest of chemotherapeutic discoveries, that of the cure of 
malaria by quinine, had never been satisfactorily explained. There was no 
evidence establishing even a probability that quinine, in such concentrations 
as can be tolerated in the blood of the living subject, would directly kill the 
malarial plasmodia, especially if these were partly screened from its action 
by their position in the interior of the red corpuscles. Morgenroth, from 
the results of his determinations by biological methods of the distribution 
of quinine in blood, is led to the conception of quinine as acting on malaria, 
in virtue of its fixation by the red corpuscles, either killing the trophozoites 
in their interior, or blocking the entry into them of the merozoites of the 
asexual cycle. On this latter supposition, it will be seen that quinine would 
act, not by killing the malarial parasites, but by rendering the blood un- 
fitted for their multiplication. They are supposed to fall a prey to the 
natural defensive substances in the plasma, because a film of quinine denies 
them access to the red corpuscles, in the interior of which they could 
continue their development in safety. There are discrepancies between 
Morgenroth's determinations of the distribution of quinine in favour of 
the red corpuscles, and those obtained by direct chemical means, which 
would still need to be reconciled before either theory of the curative process 
in malaria could be fully accepted. Meanwhile, these suggestions are of 
interest as another example of the need found, more and more, by workers 
in this field to regard an organotropic property of a drug not as detri- 
mental to its curative action but as an essential factor in the chemo- 
therapeutic process. 

VT. Remedies for Bacterial Infections. 

This same property, of fixing themselves to the red blood corpuscles or 
to the connective tissue, has been observed by Morgenroth and his co- 
workers with the higher homologues of quinine, ethylhydrocupreine 
(' optochin ') and octylhydrocupreine (' vuzin '), and with the dyes of the 
acridiue series, with which they have obtained promising results in the 
treatment of bacterial infections. In the treatment of pneumococcus 
infections by ojjtochin several factors, other than those of immediately 


lethal action of the alkaloid ou the pneumococci, appear to be concerned. 
Evidence wa.s obtained by Moore, for example, which suggested that the 
defensive reaction of the host was an essential factor in the cure, optochin, 
in doses inadequate to kill the pneumococci, rendering them liable to 
the action of specific antibodies ; and some experiments of Felton and 
Dougherty suggest that an excessive dose of an alkaloid of this class, by 
suppressing the natural defensive reaction, may even allow the fatal 
spread of an infection which a lower dose would cure. Morgenroth, on the 
other hand, emphasises the part played by the organotropic properties of 
optochin and vuzin, in enabling the red corpuscles to act as carriers of the 
drug to the 2)oint of action, and the connective tissues to form local 
depots of it. 

An acridine dye, named Trypaflavin, was under study in Ehrlich's 
laboratory in 1914 as a trypanocidal remedy, and was found during the 
war, by Browning and his co-workers, to have valuable properties as an 
antiseptic for infected wounds and mucous membranes, for which, under 
the name ' Acriflavine,' it is still used. Since the war, other dj'es of this 
series have been investigated by Morgenroth and his school, and one of 
them, called ' RivanoL' is stated to be particularly effective as a tissue anti- 
septic, especially in conditions of spreading infection due to streptococci. 



' Rivanol ' (2-ethoxy 6, 9 diamino acridine). 

In the case of ' Rivanol ' also, evidence has been brought forward that 
it is fixed by the red corpuscles and the subcutaneous tissues, protected 
thereby from excretion, or held at the point where its curative action is 
required. From these body cells it is suggested that the dye is gradually 
given up to the cocci, on which its action is exerted, by a process 
called ' transgression ' by Morgenroth. This is a process by which a sub- 
stance is passed from one medium to another, when both have strong 
afiinities for it, through a layer of an intervening medium for which it has 
no affinity, and in which it may be almost insoluble. In this process of 
depot formation, and gradual liberation of the active substance, we are 
concerned with a phenomenon which certainly has a widespread impor- 
tance for chemotherapeutic action. We have earlier seen evidence of such 
fixation and gradual release in the cases of Bayer ' 205 ' and Salvarsan. 

Another suggestive feature of the action of 'Rivanol' on streptococcal 
infections, is that .such organism.s as escape the immediately lethal effect 
of the dye appear to have lost their haemoljiiic properties, and to have 
been modified into a relativelv avirulant strain. 


VII. Conclusion. 

We have considered but a few examples of the directions in which 
chemotherapeutic investigation has proved practically fruitful, including 
some in which it shows, at the moment, the most hopeful signs of progress. 
If one considers any one group of investigations by itself, one may easily 
feel, at the same time, elated by the practical success obtained, in the cure 
of some infection which, but a few years ago, seemed beyond the reach of 
treatment, and depressed by the disharmony between the results of experi- 
ment and the theoretical conceptions, hitherto available, of the nature of 
the chemotherapeutic process. Some of the most notable practical triumphs 
in this field have resulted, not from experimental investigations based 
on theory, but from an almost empirical trial, on human patients sufEering 
from one type of infection, of a remedy which had experimentally shown 
promising results in infections of a different, and sometimes of a widely 
different, type. The partial success of tartar emetic in trypanosome infec- 
tions might have justified a hope that it would have some effect in kala-azar, 
but hardly a prediction of its really remarkable efficacy in that previously 
intractable form of infection. Still less would it have justified expectation 
of the brillant success of this same drug in infections by the Schistosoma 
or Bilharzia-worm, which but recently seemed almost beyond the hope of 
any kind of treatment. With such instances in mind, one might, but a 
year or two ago, have been tempted to suggest that the attempts at theore- 
tical investigation, of the intimate mechanism of the chemotherapeutic 
process, had contributed little to the practical achievements, and that a 
reasonably intelligent empiricism was still the safest guide. I do not think 
that the suggestion would even then have been defensible, and it would 
assuredly have been stultified by the results of the past few years. 
Patient, systematic exploration, by routes of which the initial sections 
were already mapped in the early days of chemotherapy, has in these recent 
years again led to results of major importance, both for practical thera- 
peutics and for the theoretical basis of future advance. That the original 
theoretical framework begins to show itself inadequate for the expanding 
fabric is good reason for its reconstruction ; but we may well beware of 
hasty and wholesale rejection, remembering that it served the early builders 
well. I think that it is especially encouraging to note that, though, in the 
action of almost every remedy which has proved its value in the specific 
cure of infection, there are features which cannot be interpreted by a strict 
application of Ehrlich's distribution hypothesis, the discrepancies begin 
to show a new congruity among themselves. Repeatedly we find pheno- 
mena which point to the need of modifying the theoretical structure in 
the same direction. The conception of a remedy not killing the parasites 
immediately, but modifying their virulence, or lowering their resistance 
to the body's natural defences; of a remedy not acting as such, but in virtue 
of the formation from it in the body of some directly toxic product, either 
by a modification of its structure or by its union with some tissue consti- 
tuent ; of an affinity of the remedy for certain cells of the host's body, 
leading to the formation of a depot from which, in long persistent, never 
dangerous concentration, the curative substance is slowly released ; all 
these conceptions present themselves, again and again, as necessary for our 


present rationalisation of the effects observed. It can hardly be doubted 
that they will potently influence the methods by which, in the immediate 
future, new and still better specific remedies are sought. But though our 
practical aim, in relation to the affinities of a remedy for the parasite and 
for the host's tissues, may be radically changed, the meaning of these 
specific affinities, so dehcately adjusted to a precise molecular pattern, 
remains dark. Ehrlich's chemoreceptors may no longer satisfy us, but 
we have nothing equally definite to replace them. I have endeavoured 
to indicate what seem to me hopeful signs of new contacts between bio- 
chemistry and chemotherapy. There is promise, in another direction, 
that at least some aspects of the problem of immune specificity are being 
brought within the scope of strictly chemical investigation, as in the recent 
work of Avery and Heidelberger, on the constituent of a pneumococcus 
which combines with the specific precipitin. As in Ehrlich's pioneer work 
m chemotherapy, it can hardly be doubted that an increased under- 
standing of the meaning of immune specificity, which but a short while 
ago might have seemed hopelessly beyond the range of attack by chemical 
weapons, will still influence ideas, and help to shape the course of further 
investigations, on the chemotherapeutic process. As the biological com- 
plexity of the problem is realised, it becomes increasingly a matter for wonder 
and admiration that so much of practical value has already been achieved 
— the treatment of the spirochsetal infections, syphilis, yaws and relapsing 
fever, revolutionised; Leishmania infections, kala-azar and Baghdad 
boil, and Bilharzia infections, which crippled the health of whole populations 
in countries such as Egypt, now made definitely curable; trypanosome infec- 
tions, such as the deadly African sleeping-sickness, after years of alternating 
promise and disappointment, brought now at last within the range of 
effective treatment. And if such results have already been attained, in 
a period during which practice has often and inevitably outrun theory, 
we may well be hopeful for a future in which fuller understanding should 
make for more orderly progress. 







We who are workers in the various fields of Psychology are happy in the 
knowledge that our science is rapidly developing, extending its influence 
into every sphere of human activity. The institution and the success of 
this Section of the British Association are good evidence that our colleagues 
in the other branches of natural science have recognised the claim of 
Psychology to take its place among those other branches. And, though 
in Great Britain there are still all too few Chairs of Psychology, in Canada 
and America the Universities and Colleges are now providing abundant 
opportunities for teachers, students, and research workers, opportunities 
that are being eagerly and fully used. 

Yet, in spite of this happy state of affairs, there is manifested among 
us psychologists a certain uneasiness as to the status of our science, an 
anxiety lest the psychologist be regarded as not quite really and truly a 
man of science. This anxiety is, I think, exerting an unfortunate influence 
on the development of our science, an influence which shows itself in two 
principal directions. 

On the one hand is a group of psychologists who, actuated by the 
desire to mark off an exclusive field of study as their province, define 
psychology as the science of consciousness and would confine themselves 
to the analytic description of conscious states as complex conjunctions of 
elements or units of some kind. On the other hand are those who, feeling 
that such analytic description, whether it resolves consciousness into a 
complex of sensations or atoms of consciousness, or into larger more 
complex units (the so-called configurations or Gestalten), brings but little 
light on human nature and conduct, and can hardly claim to be in itself 
a science, are driven to the opposite extreme ; they ignore this realm of 
facts, alleged to be the peculiar and distinctive field of psychology, and 
they would bring to the study of man only those methods of observation, 
description, and explanation which are used in the physical sciences. 
These two tendencies, which, when they are carried to extremes, result 
respectively in what is unfortunately called ' structural psychology ' and 
in ' behaviorism,' although so different in their outcome, are but two 
expressions of one desire, the desire to make psychology conform to some 
preconceived notion of what a science is or should be. The ' structuralist ' 


aims at marking out a peculiar and exclusive field of objects of study. 
The ' behaviorist ' slavishly accepts the physical sciences as his model, 
and seeks safety from the charge of being unscientific by confining himself 
to the use of the methods of observation, description, and explanation 
current in those sciences. 

Although a very considerable number of psychologists are following 
these two widely divergent lines (especially, perhaps, in America), I may, 
I think, take it for granted that to the majority of us neither line is 
satisfactory. We feel that both are the expression of a lack of courage ; 
of an undue timidity. In face of the imposing edifice of the physical 
sciences, the one party shrinks back and seeks to define a little field of 
knowledge altogether peculiar to itself, within which the psychologist can 
disport himself at his own sweet will without fear of collision or conflict 
with the other sciences ; the other party seeks safety by taking cover in 
the bosom of the herd, carefully avoiding all speech or action that might, 
by marking him as a distinctive variety of the species scientist, bring 
upon him the suspicious glances of other members of the herd. 

There is yet a third large group of psychologists who, moved by the 
same desire as these others, yet seeing that neither group achieves, nor 
can hope to achieve, a satisfactory science of human nature and conduct, 
seek to escape from the limitations of both groups by combining the 
procedures and the conclusions of both. These adopt the analytic 
description of consciousness (whether of the ' sensationists ' or the ' con- 
figurationists ') and they accept the mechanistic explanation of conduct 
of the' behaviorists ' ; and they seek (by the aid of the principle of psycho- 
physical parallelism or of epiphenomenalism) to put the two together in 
parallel columns, to form what can only be called a lame apology for a 

The very fact that this undue timidity has produced these two widely 
divergent and aberrant (not to say abortive) types of psychology is its 
sufficient condemnation. We should take warning from it ; we should 
be led by it to see that a policy of courage is also the policy of safety. I 
urge that we psychologists are now numerous enough and strong enough 
to stand together, to form our own herd, a herd in which our more timid 
members may find the shelter which they crave. In other words, I urge 
that the time has come when the students of human nature should boldly 
claim autonomy, or, at any rate, dominion-status, for their science ; they 
should invoke and boldly apply the principle of self-determination. 

I urge that this policy of safety through boldness is justified and 
demanded at the present time by considerations of three kinds, in addition 
to the fact of the unsatisfactory results of the policy of timidity which 
I have already indicated. 

First, psychology has now at its command an immense mass of data, 
facts of introspective observation and facts of behaviour, demanding to 
be synthesised in our science, not merely to be placed side by side in 
parallel columns. 

Secondly, psychology has found many important fields of application, 
in education, in medicine, in industry, in the social sciences ; and all 
these require a psychology, a science of human nature, very different from 
the mere description of consciousness and from the mechanistic explanation 
of behaviour, and different also from the parallel-column psychology. 

Q 2 


Thirdly, the policy of boldness is abundantly justified by the present 
state of the other natural sciences. 

I propose to dwell briefly upon each of the three classes of consideration 
in turn. And in relation to each I desire to urge that the most fundamental 
need of psychology, the first demand to be met by the policy of boldness, 
is the adoption without reserve of the conception of purposive striving 
as valid, useful, nay, indispensable, and therefore true. 

The life of man from birth to death is one long series of purposive 
strivings. Sometimes, as when he plans his career and sets out to build 
up a home and a family, his goal is remote and somewhat vague, defined 
in his mind in general terms only ; sometimes it is precisely and exactly 
defined, as when he goes to eat his favourite dinner at his favourite table 
in his club ; sometimes it is near and yet but vaguely defined, as when, 
with open mouth and feeble movements of head and trunk, he seeks the 
nipple of his mother's breast ; or when, during an absorbing after-dinner 
conversation, he reaches out to put a piece of candy in his mouth. There 
is a vast range of differences in respect of the nearness or remoteness of 
the goal ; and in respect also of the clearness, fullness, and adequacy with 
which he thinks of his goal. And there is also a wide range of differences 
between his successive strivings in a third respect, namely, in respect of the 
urgency, the intensity, the concentration and output of energy manifested 
in his striving at any movement. Yet, in spite of these wide differences, 
the striving is always one aspect of his waking life. And even in his dreams, 
as we now realise, thanks to Professor Freud, the striving goes on, 
bringing what strange and partial satisfactions it may to the buried, 
thwarted and denied tendencies of his nature. From top to bottom of this 
scale of strivings we have to do with the same fundamental phenomenon. 
In the instances near the top, the more developed modes of mental Ufe, 
involving the solving of a defined problem, the thinking out of a plan, we 
all recognise the purposive nature of the striving. The goal, as envisaged, 
governs the movements of both mind and body. 

In instances at the lower end of the scale, introspection, or rather 
retrospection, inevitably fails to seize and report the thinking of the goal 
as distinct from the perceiving of the situation of the moment. Yet the 
continuity of the series justifies us in regarding its lower members as 
fundamentally of the same nature as its upper members, and in applying 
the term ' purposive ' to them all alike. 

Even in laboratory experiment, where the conditions are commonly 
so set as to reduce the striving factor to a dead level of uniformity and mono- 
tony, it refuses to be ignored for ever ; and so, after a generation of experi- 
mentation that ignored it, it is rediscovered and reinstalled in its place of 
fundamental importance, disguised under some such terminology as 
' determining tendency,' or ' motor set,' or ' conditioned reflex,' or ' pre- 
potent reflex,' or what not. 

Under all three of the types of psychology we have noticed, this most 
vital, essential, distinctive aspect of human life escapes the psychologist. 
For it cannot be described as either a sensation or a configuration {Gestalt). 
And it is not to be discerned by an inspection of the detailed movements 
of the limbs or of other bodily organs, no matter how exact. 

Nor can it be restored or recovered in the psychology of parallel columns. 
It can be discerned in others only by sympathetic observation and inter- 


pretation of the course of their lives. If, under the influence of any meta- 
physical dogma or any supposed rule of method, you overlook it from the 
start, you cannot introduce it into your otherwise completed picture of 
human nature, as an element to be added to and put alongside others 
already described. 

It is too all-pervasive for such treatment. As well might the landscape 
artist, after painting a picture without atmosphere, attempt to add it by 
drawing a smear of paint across the whole. This is the difficulty found 
by students who have been brought up on the parallel-column psychology, 
as I know from instances of such students who have found difficulty 
with my frankly purposive ' Outline of Psychology ' ; nor are such 
students helped to a truer view of human nature by those books on 
psychology which, after describing man after one or other of the three 
fashions we have noted, throw in perfunctorily as an afterthought a 
cha23ter on 'The Will.' If striving has been ignored throughout the com- 
position, 'The Will' cannot be added to the picture as a finishing touch. 
Having learnt to look upon man as a bundle of mechanical reflexes, a 
superior penny-in-the-slot machine, whose workings are mysteriously 
accompanied by various ' elements of consciousness,' they can find no 
place in their completed picture for yet another element called ' a purpose ' ; 
it refuses to fit in among the other blocks ; there is no room for it, and, as 
they think, no need for it; and it seems to them quite an ambiguous, not 
to say shady and suspicious, character ; at best it appears to them as a 
disturbing intruder. 

But let the budding psychologist ponder some phase of human life 
that is dominated by some strong but thwarted desire. Let him consider 
the strange yet familiar case of Romeo seeking the Juliet who is forbidden 
to him. How this desire to see, to hear, to touch the loved one dominates 
his life, waking and sleeping ! How it fevers his blood ; wears him to a 
shadow ; keeps him running to and fro, scheming, trying, hoping, despond- 
ing, exulting, despairing, and always desiring ! The desire governs all 
his thinking and acting ; the most rooted habits and mental associations 
are as nothing in the course of this torrent of purposive activity, all directed 
to Nature's most imperative goal. 

Can we accept any account, any description or explanation of human 
life, which leaves out of the picture this all-important aspect that we call 
impulse, desire, striving towards a goal ? 

When we turn to the fields of applied psychology, the same truth 
stares us in the face. In every field we find that the most urgent practical 
problems are concerned with the striving aspect of human nature. The 
most fundamental task of the educator is to awaken an interest in and a 
desire for knowledge and self-development. The psychiatrist must study 
and redirect if possible the conflicting desires of his patient, his subcon- 
scious as well as his conscious motives and impulses. 

The personnel manager is chiefly concerned with incentives, rewards, 
jealousies, rivalries, discontents, loyalties, ambitions, and aspirations. 
The lawyer, the judge, and the jurymen are primarily concerned to deter- 
mine motives, intentions, and responsibility. The politician, the economist, 
and the moralist are, or should be, primarily concerned with relative values 
and the means to make real or actual the highest values of mankind, by 
harmonising and co-ordinating the conflicting motives of our social life. 


In all these cases a psychology that ignores the all-pervading purposive- 
ness of human life is of no use ; for, if it is consistent, important words 
that are essential to the intelligent discussion of human affairs (such words 
as motive, intention, desire, will, responsibility, aspiration, ideal, striving, 
effort, interest) are of no meaning for it ; or, if they are used, are used 
with a meaning so thin and so different from that of ordinary discourse, 
that profitable converse with the practical man is impossible. 

I leave that large topic with these few words and pass to my third 
consideration in support of the policy of boldness. Thirty to forty years 
ago, when I began to study science, considerable moral courage would 
have been required to insist upon the purposive nature of man. For at 
that time the great wave of scientific materialism was still but little past 
its climax. It was the day of Spencer and Huxley, of Clifford and Tyndal, 
of Lange and Weismann, of Verworn and Bain. The world and all the 
living things in it were presented to us with so much prestige and confidence, 
as one vast system of mechanistic determination, that one seemed to be 
placed before two acutely opposed alternatives : on the one hand, science 
and universal mechanism ; on the other hand, humanism, religion, 
mysticism and superstition. 

But to-day how different is the situation ! Even at the date I speak of, 
a few great physicists warned us against regarding the principles of physical 
science as adequate to the interpretation of human life. And to-day those 
few voices have swelled to a chorus which even the deafest biologist can 
hardly ignore. Einstein and Eddington and Soddy and a score of others 
repeat the warnings of Maxwell and Kelvin and Poynting and Rayleigh. 
And the physical universe of eternal hard atoms and universal elastic 
ether, the realm of pure mechanics, has become a welter of entities and 
activities which change and develop and disappear like the figures of the 
kaleidoscope. The psychologist who would believe in the efficiency of 
human effort no longer needs to fling himself in vain against the problem — 
How can Mind deflect an atom from its predetermined course ? For the 
atoms are gone ; matter has resolved itself into energy ; and what energy 
is no man can tell, beyond saying— It is the possibility of change, of further 

In physiology the mechanistic confidence of the nineteenth century is 
fading away, as the complexity of the living organism is more fully realised, 
as its powers of compensation, self-regulation, reproduction and repair are 
more fully explored. 

In general biology the mechanistic Neo-Darwinism is bankrupt before 
the problems of evolution, the origin of variations and mutations, the 
differentiation and specialisation of instincts, the increasing role of intelli- 
gent adaptation, the predominance of mind in the later stages of the evolu- 
tionary process, the indications of purposive striving at even the lowest 
levels, the combination of marvellous persistency of type with indefinite 
plasticity which pervades the realm of life and which finds its only analogue 
in the steadfast purposive adaptive striving of a resolute personality. 

All these considerations, I say, should encourage us to claim autonomy 
for psychology, the right to choose, shape, and refine its own fundamental 
conceptions. We should now easily find the courage to be anthropo- 
morphic in describing man. Instead of accepting the abstract conceptions 
of physical science and attempting to build up from them a plausible 


mechanical dummy which shall stand for man in our science, let us frankly 
acknowledge that man is that thing in all the world with which we have 
the most intimate acquaintance. Let us begin by accepting him for 
what he seems to be, a thinking being that strives to attain the goals he 
desires, to realise his ideals, sometimes succeeding, often failing, but 
always striving so long as he lives. Let us try to understand the history 
of these tendencies to strive, as they are revealed in the individual and the 
species ; to understand more nearly our knowing, our imagining, our 
recollecting, our judging and reasoning, as they serve us in our strivings 
for the attainment of our goals. 

As we progress with this task, let us cautiously extend the same 
principles of explanation to the animals of successively lower lev.els. And, 
when in this way we shall have gained some understanding of the life of 
the animalcule, we shall, perhaps, be able to begin to understand the 
physiology of the complex organism in its broader aspects. Instead of 
trying to illuminate human society by likening it to an animal mechanism, 
as was the fashion of the nineteenth century, we may find that we can 
profitably invert the process, that we can illuminate the complex organism 
by likening it to a well-organised harmonious human society, a society 
which can adjust itself to a thousand disturbances and can recover itself 
from grave disorders, just because and in so far as each member, endowed 
with limited powers of adaptation, steadfastly strives always to achieve 
the goal prescribed by his own nature and by his active relations with all 
his fellow-citizens. 

But here we shall be met again by the cry of the timid psychologist. 
' You are not scientific,' he will say, ' for you are disregarding the 
fundamental postulate of all science, namely, that all events are strictly 
determined, that mechanistic causation rules universally.' To this we 
can only reply by exhorting him once more to have courage, assuring him 
that 'Not all propositions made by all philosophers are true, neither does 
a proposition become true through being frequently repeated.' 

Let us be content to postpone metaphysics and to start out from two 
indisputable empirical facts : first, the fact that sometimes men create 
new things, such as great works of art and literature and new scientific 
formulae. Secondly, the fact that, when the normal man simply and 
strongly desires a certain end and perceives certain bodily movements 
to be means to that end, those movements follow upon that desire and that 
perception. Here are well-established empirical generalisations from 
which we may confidently start out, refusing to be held up by questions 
at present insoluble, such as — How can consciousness deflect the path 
of a single molecule in my brain ? Answers to such questions are quite 
unnecessary as foundations for purposive psychology. It is in the highest 
degree probable that, as Science progresses, it will become clear that such 
insoluble questions have been wrongly stated and should never have been 

Let us not deny ourselves the right to build up a psychology that may 
be of use and value to our fellow-workers in the social sciences, because 
we cannot at present answer the most difiicult of all questions. The 
physicist is equally nonplussed if you ask him comparable questions, 
such as — How does one molecule attract or repel another ? What is the 
nature of chemical affinity ? What is electricity ? But he does not 


suspend his researclies because his fundamental conceptions and assump- 
tions are disputable and disputed ; nor does he turn to some other branch 
of science in order to borrow from it others that have more prestige. Let 
us follow his example. 

Let us gather our facts of human nature by objective and by intro- 
spective observation. Let us make our empirical generalisations and 
correlations of these facts, building up our own science in our own way. 
Let us boldly affirm that, just as the physical sciences do not proceed 
deductively from any system of exact abstract propositions, so also 
psychology, the most concrete of the sciences, is not required by any 
higher authority to accept or formulate any abstract propositions as an 
unchanging deductive basis. 

It may be that eventually men of science will agree that there are in 
the universe two ultimately different kinds of process, the mechanistic 
and the purposive, the strictly determined and the creative, the physical 
and the mental. Or it may be that, eventually, one of these may be shown 
to be merely an appearance of the other, an appearance due to the present 
limitations and imperfections of our understanding. At present we 
cannot decide this issue. 

But, if I attempt to guess at the future development of Science, I 
incline to follow the lead of the most powerful intellects of all ages, and to 
predict that, if such resolution of the two types of process into one shall 
ever be achieved, the purposive type that we regard as the expression of 
Mind will be found to be more real than the other. 






The President of the Association will have expressed the satisfaction 
which all the Sections feel in meeting for the fourth time in the history of 
the Association in the great Dominion of Canada. To Section K the almost 
overwhelming size of the country and the great diversity of vegetation, 
both natural and artificial, must have an especial appeal. 

Last year the President of Section K had to deplore the loss of three 
prominent botanists. I am less unfortunate in that our loss this year is 
far lighter. We have, however, to regret the death of Thomas Frederick 
Cheeseman, a distinguished worker in systematic botany who devoted 
himself to the study of the flora of New Zealand. 

In deciding on the subject of a Presidential Address, the vastness of 
Canada's agricultural and sylvicultural interests can hardly be overlooked, 
even in a section the interests of whose members are in the main those of 
pure botany. It appeared to me appropriate that if possible some aspect 
of pure botany should be chosen which would have at least impUcations 
in applied botany. The subject of disease is, of course, one of great 
moment wherever plants are massed together in artificial cultivation. 
Some aspect, therefore, of plant pathology seemed a fit subject for an 
address on such an occasion, since in it we have a branch of botany securely 
based on scientific interest and firmly buttressed by economic importance. 
Some consideration of disease in plants seemed peculiarly apposite also 
when it is recalled that at the last meeting of the British Association at 
Toronto, in 1897, the President of this Section was Professor Marshall 
Ward, the first English plant pathologist of the modern school. The value 
of his contributions to our knowledge of disease in plants is recognised by 
all ; that he should have been cut ofE in his prime, British botanists will 
long deplore. 

It is significant of the growth of botany in all its branches that Marshall 
Ward set himself as his presidential task a wide survey of the fields of 
mycology, parasitism, and fermentation. Needless to say, the task that 
any President of Section K can at the present time essay must be one of 
much smaller compass. 

In the field of plant pathology which has been so assiduously cultivated 
of late years, attention has been mainly focussed on the study of the life- 
history and mode of infection of fungal and bacterial parasites, and on 
the methods of controlling infection. The relationship of host and parasite 


and their mutual reactions have until recently secured but scant attention. 
It is some of these physiological aspects of parasitism that I propose to 
take as the subject of my address. 

In dealing with any aspect of this branch of Botany one is faced by 
the fluidity of our conception of parasitism.^ It may range from the simple 
relationshijj to its host of a Sooty Mould or of Bolrytis cinerea to the 
complicated relationship found in the Uredineae. 

The physiological aspects of parasitism in the case of a fungus like 
Bolrytis cinerea are apparently of the simplest when once it has entered the 
host. The cells of the host plant are killed in advance by the secretion of 
an enzyme of a pectinase type and the dead tissues serve as food for the 
parasite. On the other hand, in the case of the jsarasitism of fungi belonging 
to the Uredineae and Erysiphacese (and probably the Ustilaginales, and 
possibly also the Exoascacese) we have a complicated relationship in 
which there is a definite physiological resistance of the host cells to the 
attack of the fungal organism. There is action and reaction, the balance of 
forces sways this way and that — in favour of the host or the invader — and 
there may for a time be an equilibrium in which the fungus is held in check 
but not vanquished. 

The existence of this reaction between the host and parasite which we 
find in the Rust Fungi, and which I shall discuss more in detail later, 
has only been realised comparatively recently, and thus, on the botanical 
side, the physiological aspect of disease has been largely overlooked. 
Disease is abnormal physiology, and it is necessarily the result of the inter- 
action of the physiological processes of the host and parasite. This inter- 
action between the physiological jarocesses of the two organisms has long 
been recognised in animal disease ; it exhibits itself in the specific symptoms 
which are characteristic of disease in man and the higher animals generally. 
The specific symptoms of such diseases were recognised long before the 
' germ basis ' of disease was substantiated, and thus the attention of animal 
pathologists was inevitably turned towards a study of the physiological 
response of the affected organism. These special reactions are in general 
so clearly marked that the nature of an infectious disease in man can 
generally be determined without reference to the invading organism. 
In plants, on the other hand, the symptoms of parasitic disease are highly 
generalised, a large number of infectious diseases displaying the same 
symptoms. It is thus often very difficult, and sometimes impossible, to 
determine the nature of a plant disease without knowledge of the nature 
of the parasite. This distinction between diseases of plants and animals 
is, however, not a fundamental one. The point must be stressed that 
although the symptoms of different parasitic diseases may be superficially 
similar, yet the existence of physiological reactions of the host specific for 
each infection can hardly be doubted when once it is recognised that disease 
is abnormal physiology, the physiological processes of the host being 
modified by the physiological processes of the parasite. At the present 
time we are unable to distinguish the special reactions which the clash 

1 Parasite (irapk o-itos) means etymologically ' beside the victuals.' As Sir Ray 
Lankester has pointed out, it was the Greek term applied to those attending sacrifices 
to obtain food. It had no suggestion of meanness till rich men for purposes of display 
cultivated ' hangers-on.' In its primary sense it can be used for any ' co-liver ' whether 
or no it does harm. 

K.— BOTANY. 235 

of the two sets of processes must produce in the host. With improvements 
in our methods of biophysical and biochemical analysis we may anticipate 
a time when these hidden reactions may be revealed and a new basis for 
the classification of plant diseases established. 

Another striking difference between animal and plant pathology which 
is worth insisting upon is that relating to disease resistance. Disease 
resistance is shown both in plants and animals, but the particular type of 
immunity which has been most clearly studied by the workers on the 
animal side is acquired immunity, i.e. that type of specific resistance which 
is the result of one attack of a specific disease. Such imnmnity must 
have forced itself on man's attention from very early times, and it is by a 
study of such resistance that animal bacteriologists — building firmly on 
the work of Pasteur — have developed the modern treatment of disease by 
the injection of dead organisms and of the blood fluid of animals containing 
suitable antibodies. The development of such vaccine and serum therapy 
should, I think, be rightly considered as one of the most remarkable achieve- 
ments of modern biology. 

On the other hand, the problem of immunity in plants is a far more 
difficult one than that with which the animal pathologist is faced. The 
acquired immunity due to one attack of a disease which is so common 
in animals is unfortunately quite unknown in plants, at least in relation 
to definite disease. The modern view of recovery from infectious bacterial 
disease in animals is that it is due to a very well-marked and highly 
specialised reaction of the invaded organism. Part at least of the reaction 
is the development of antibodies which neutralise the toxins produced by 
the invading bacteria and help to bring about their death. It is true 
that in the Erysiphacege and the Uredineas and in certain cases of 
endotrophic mycorhiza, and in the well-known orchid fungus, the invaded 
cells show a very marked reaction which may lead to the death, and 
sometimes to the digestion later, of the invading hyphae. These, however 
are not cases of ordinary disease and the cells show no acquired resistance. 

Again, whatever may be the behaviour of individual plant cells when 
attacked, one never finds that general bodily reaction which is so marked 
and characteristic of many infectious diseases in the higher animals. The 
parts of the plants are, of course, much less highly correlated than those 
of the animal body ; there is no circulating blood stream by which the 
most distant cells of the body can with great rapidity be brought into 
physiological relationship. Even in the case of the highly specialised 
parasitism of the Rust Fungi, where there are obvious complex physio- 
logical reactions between host and parasite, we find no general reaction 
by the plant, but cells or small groups of cells carry on a struggle with the 
invading bacteria and hyphae apparently in complete independence. It 
follows that in the absence of any suitable reservoir — such as the blood 
stream of animals supplies — in which toxins and antitoxins may be sought, 
the likelihood of their demonstrations, should they be produced, is very 
slight. The absence in plants of a general bodily reaction to disease would 
seem also to preclude the possibility of the application to them of serum 
therapy. If, in spite of the absence from plants of the acquired resistance 
which is the basis of serum therapy in animals, such sera could be 
prepared, there would be the great difficulty of distributing such substances 
throughout the plant. Another and apparently insuperable barrier to 


success would be the continued development exhibited by the plant, which 
would necessitate the endowment of the plant body not only with acquired 
immunity to the disease in question, but an immunity of such a type as 
would be passed on to the newly developing organs. A reaction of the 
nature of inherited, acquired immunity would have to be attained, and 
this in view of the experience of animal bacteriologists is unlikely of 

Immunity and resistance to diseases are, of course, well known in 
plants, but they are of the nature of natural immunity. Plant pathologists 
need not, I think, reproach themselves for the small progress that has been 
made in the elucidation of the nature of this resistance, for the basis of 
natural immunity in animals remains still very obscure, although the 
physiological field has been worked for a much longer term of years by 
animal than by plant pathologists. 

Some of the processes concerned in the achievement of parasitism in 
plants may now be considered. The question of the mode of entry of a 
parasitic organism into a host plant is one of great physiological interest 
and importance ; for a barrier which the would-be invader cannot pass is 
one of the most obvious means of defence against fungal attack. Apart 
from entry through wounds, there are two chief modes of entry of the 
aerial parts of plants, either through a stomatal pore or by actual pene- 
tration of the superficial cells of the host. The entry through the stoma, 
at least in the case of a germ-tube, is clearly the most facile one, and it 
is somewhat of a biological puzzle that any germ- tubes should follow the 
hard road of epidermal-cell-penetration rather than the easy path of 
stomatal invasion where moisture and food material can so easily be 
obtained.^ Yet the germ-tubes of Botrytis, Colletotrichum, and Fusidadium, 
for example, and the germ-tubes of the sporidia of Uredinese, apparently 
never enter the open stoma but proceed to bore their way laboriously 
through the epidermis. The case of the Rust Fungi just mentioned is 
particularly striking, for the germ-tubes of the uredospores and aecidio- 
spores on the other hand invariably enter through the stomata. 

The nature of the reaction which brings about the stomatal type of 
entry is still very obscure. It is frequently assumed that the entry is in 
response to some hydrotropic reaction, that the germ-tube passing over 
the stomata finds itself exposed to a stream of water vapour difiusing 
out of the pore and thus a tropistic reaction is produced. Balls, some 
years ago, showed that the uredospores of Rust Fungi when placed on a thin 
perforated sheet of rubber above a water surface developed germ-tubes 
which passed through the perforations towards the water. This interesting 
experiment demonstrates that the germ-tubes in question are capable of 
hydrotropic curvature, but it does not show that the entry into the stoma 
is due to such a reaction. In the experiment with the rubber sheet there 
must have been marked differences in the concentration of water vapour 
on the sides of the membrane. In the case of a germinating spore on the 
surface of a leaf and under the conditions in which infection usually occurs, 
the differences in concentration on the two sides must be very slight. 
The surface of the leaf would be covered with layers of air very nearly 

^ A germ-tube without the capacity for penetration of the epidermis would be at 
a disadvantage on a non-stomatal surface. 

K.— BOTANY. 237 

saturated, and the germ-tubes in question are in close contact with the 
surface of the epidermal cells through which a certain amount of cuticular 
transpiration is occurring.^ 

The possibility that the entry through the stomata is due to a chemo- 
tropic response to some volatile substance (such as a volatile organic acid, 
aldehyde or ester) emanating from the leaf tissue and diffusing through 
the stomata ought not to be overlooked. That volatile substances from 
plant tissues can stimulate or retard germination has been shown by 
Brown* and by Neger/ and the ascription by Cooley of ' scald ' in apples 
to the accumulation in closed chambers of acetaldehyde volatilising from the 
fruit tissue is well known. It would seem also that a positive thermotropic 
reaction ought not to be overlooked in considering the physiological 
aspects of fungal penetration of the host. Penetration of the surface 
of the leaf by a germ-tube occurs under conditions of high humidity and 
very slight air movement, conditions which would tend to reduce the heat 
losses of the leaf to a low level. In such circumstances the respiratory 
processes of the tissue might easily be responsible for a leaf temperature 
of the order of 1° C. above that of the air.* The penetration by germ- 
tubes of such surfaces as those of gelatine and collodion show, however, 
that this cannot be a main factor. 

The question of the physiological processes concerned in the other 
method of entry, that through the epidermal cell, also requires further 
elucidation, and the conditions surrounding a germ-tube developing in a 
drop of water on a leaf may be considered. When the work of Miyoshi 
on the chemotropism of fungi and of pollen tubes appeared in 1894, it was 
naturally assumed that entry was due to a positive chemotropic response 
of the germ-tube or fungal hypha to some substance diffusing from the 
surface cells of the host into the drop containing the germinating spores. 
Considerable doubt, however, was thrown on the interpretation placed by 
Miyoshi on his results by the work of Clarke and of Fulton, who demonstrated 
that fungi showed a marked negative chemotropism to their own waste 
products. It remained questionable then as to whether fungi exhibited 
any positive chemotropism towards nutritive substances. Graves,' 
however, by allowing for the negative chemotropism towards staling 
products and giving it a rough quantitive measure, was able to show that, 
in addition to this negative reaction, there is a definite positive reaction 
towards such substances as cane sugar and turnip-iuice. A tropism of 

* The cogency of this argument is reduced by the fact that the same difficulty arises 
in the case of all chemotropic reactions. The differences in the concentration of a 
sugar on the two sides of a hyphal tip, which responds to a diffusion gradient by a 
curvature, must in many cases be exceedingly small. It seems possible that in all such 
cases other factors may be at work. 

* W. Brown : ' Studies in the Physiology of Parasitism IX. ' Annals of Botany, xxxvi., 
285, 1922. 

* F. W. Neger : ' Forderung der Keimung von Pilzsporen durch Exhalationen von 
PflanzenteUen.' Naturw. Zeit. f. Land- u. For.ttwirtschaft, ii., 484, 1904. 

' For the latest leaf -temperature measurements of crop plants see E. C. Miller and 
A. R. Saunders (J. Agric.Res., XXVI., 15-43, 1923). who have made 20,000 observations 
of such temperatures. Except in direct sunlight and in wilted leaves they find only 
slight differences between the temperature of the air and of the leaf, but, as stated 
above, the conditions suitable for infection are of a special kind. 

'A. H. Graves: 'Chemotropism of Rhizopus nigricans.' Botan. Gazette, Lsii., 
337. 1916. 



this kind seems, however, insufficient to explain the reaction of germ-tubes 
towards the surface of a host plant. The germ-tubes of Botrytis developing 
in a drop of turnip-juice will penetrate the surface of a bean leaf ; and as 
the turnip contains substances which strongly attract germ-tubes (at least 
those of Rhizopus),it seems unlikely that the concentration of any attractive 
substances which may diffuse through the cuticle would be sufficient to 
produce a stronger response than that due to the comparatively high 
concentration of the active substances in the drop. Again, Dr. Brown 
has shown in an unpublished observation that germ-tubes of Botrytis 
growing in turnip-juice will penetrate a thin sheet of paraffin (about 10 [x 
in thickness) which is floating on the same fluid. In such cases where a 
positive chemotroi^ism appears very unlikely, the only other possible 
reactions which might be at work seem to be a negative chemotropism 
of the germ-tubes towards its own waste products, or a positive reaction 
towards the surface with which the germ-tube is in contact. If such a 
negative reaction were the main factor in penetration, one would expect 
the germ-tubes of any fungus, such as Penicillium or Rhizopus, to enter a 
bean leaf from turnip-juice ; this, however, does not occur. Furthermore, 

Fig. 1. 

Fig. 2. 

it may be argued* that there will be a higher rather than a lower con- 
centration of waste products on the side of the germ-tube tov/ards the 
substratum (fig. 1), owing to the difficulty of the escape of such products 
in this direction. The question really resolves itself into that of the 
nature of the waste products and their relative rate of diffusion through 
the water of the drop on the one hand, and through the epidermal cell- 
wall on the other. If the waste j^roducts can diffuse with fair rapidity 
through the cuticle and epidermal cell-wall and so escape into the general 
body of the leaf, or if they are taken up in some way (possibly by 
adsorption) by the host cells, then it is quite possible that the concen- 
tration on the lower side towards the host tissue may be such as to lead 
to a growth towards that host surface. The probability of a negative 
chemotropism of this k nd playing any considerable part in the responses 
of the germ-tube which lead to penetration does not, however, seem very 
strong. Such a chemotropism certainly does not prevent the germ-tubes 
of such fungi as Botrytis and Colletotrichum fixing themselves firmly to an 
impermeable glass surface. 

If both positive and negative chemotropism are excluded it would seem 
that a contact stimulus must play the major part in the entry of a parasite 
* As Dr. W. Brown has suggested to me. 

K.— BOTANY. 239 

into the epidermis of the host. This response to contact with a solid 
substratum is usually termed thigmotropism, though stereotropism would 
seem to be the more satisfactory term. That the germ-tubes and hyphfe 
of many fungi (such as Botrytis, CoUetotrichmn, Sclerotinia Libertiana) 
exhibit a stereotropic response is, of course, easily demonstrated by growth 
of such fungi in hanging drops on a glass surface. The question then arises 
as to whether stereotropism is the sole or main cause of the growth response 
which leads to entry. If a tropism of this kind be the main factor, one 
would expect the penetration of any surface (such as a leaf) of not too 
great resistance by any germ-tube responding to a contact stimulus, i.e. 
an entry quite non-specific.^ At present the data available do not seem 
sufficient to answer this question. The problem of the mechanism of 
infection requires investigation from this j)articular angle. Some light 
on the matter could no doubt be obtained by germinating together the 
spores of two parasitic fungi, say A and B, first on the host of A (which 
B does not infect), and then on the host of B (which A does not infect), and 
comparing accurately their responses on the two substrata. It is the 
melancholy experience of physiological work that a simple explanation 
of any process is almost certain to be wrong. It would therefore seem 
unlikely that stereotropism alone is responsible for penetration. How 
complex is the relationship is shown by another observation of Dr. Brown's 
that germ-tubes of Botrytis cinerea are unable to penetrate the epidermis 
of an uninfected leaf of Eucharis amazonica, but they will bore through it 
when tfie mesophyll tissue below is cut away, even when the leaf so 
treated is ' backed ' with agar. 

The question of the actual mechanism of entry is of considerable 
physiological interest. A number of studies by Brown, Blackman and 
Welsford, Boyle, and Dey ^^ have been published which bring forward 
evidence for the view that the entry of a germ-tube through the cuticle 
of the host is a purely mechanical process in which enzymes play no part. 
The evidence for this is in part directly observational. When the process 
of entry is carefully followed in such forms sls Botrytis cinerea,CoUetotrichtim, 
Sclerotinia Libertiana, the sporidia of Piiccinia graminis, it is found that 
the germ-tubes or appressorea become firmly attached to the surface of 
the host before entry, and no swelling of the cuticle can be observed prior 
to entry. Furthermore, entry is usually by a very fine infecting hypha 
(fig. 2), and at the actual point of entry of such hypha there is no rounding 
of the contours of the cuticle as we should expect if enzymes were at work. 
There is also the additional point that no enzyme is known that is able to 
dissolve cuticle. The injection into an organ, such as a leaf, of an extract 
of the germ-tubes of Botrytis is a very convenient way of preparing sheets 
of cuticular material. The resistance of cuticle to bacterial attack is well 
shown by the composition of brown coal, which often consists very largely 
of cuticular material. 

If the germ-tube is to exert sufficient force to bore its way through the 

' In the case of the Uredineae the entry through a stoma is quite non-specific, for, 
as Miss Gibson showed, the germ-tube of almost any Uredine will enter the stoma of 
almost any leaf, but the establishment of parasitism depends upon the suitability of 
the host. 

'" 'Studies in the Physiology of Parasitism,' Annals of Botany, xxix.-xxxv., 


resistant cuticle, it is evident that it must have some point d'appui against 
which the force can be expected. There must clearly be some adhesion 
of the germ-tube to the substratum or else the development of an outgrowth 
from the germ-tube will result, not in penetration, but merely in the forcing 
the tube away from the surface. It was originally suggested " that the gela- 
tinous sheath which can be demonstrated round the germ-tubes of Botrytis 
cinerea, and of some other parasitic fungi, is the main factor in the close 
attachment of the tube to the substratum. Further consideration, 
however, suggests that the essential preliminary to penetration is the close 
adhesion of the tip of the germ-tube to the surface to be penetrated. This 
close adhesion to the surface to be penetrated is a constant feature of 
epidermal infection, whether we are dealing with Botrytis cinerea, Sclerotinia 
Libertiana, Puccinia graminis (sporidia), or the case of Colletotrichum where 
the tip of the germ-tube becomes converted into a dark-coloured, thick- 
walled appressorium from which the infection-tube grows out later. In 
this adhesion the two gelatinous sheaths may play some part, but when 
one considers the ' microscopic ' closeness of the contact it would seem 
clear that molecular forces must be at work, so that once they are brought 
into such close relationship the two surfaces would necessarily adhere. ^^ 
This sheath may, however, be of use in preventing the germ-tube from 
being easily washed ofi the surface on which it is growing and also in 
giving the germ-tube the attachment necessary if the tip is to be pressed 
firmly against the surface of the leaf or other organ. Once, however, 
the two surfaces are pressed together they should adhere in the' manner 

It will be noted that the adhering surface from which the infection 
tube grows out is in general large compared with the cross section of the 
actual peg-like infection hypha which bores through the cuticle (fig. 2). 
This hypha is very small, and in the case of sjjoridial infection in Puccinia 
and infection by Synchytrium endobioticum it is of extreme tenuity, so that 
in the epidermal wall itself it can only just be observed. The absolute 
pressure required to push such a minute infection hypha through the wall 
would be very small, and the forces of adhesion which hold the tip of the 
germ-tube (or the body of the zoospore in S. endobioticum) to the surface 
of the host cell would seem to be more than sufficient to resist the back 
pressure resulting from the outgrowth of the infection tube. The processes 
concerned in the development of this outgrowth are probably very similar 
to those concerned with the development of a lateral branch on a hypha. 
If one assumes that the cell-wall of the germ-tube becomes softened over 
the appropriate area, then the osmotic pressure of the contents of the germ- 
tube should be more than sufficient to overcome the resistance of the cuticle 
and the sub-cuticular layers of the cell-wall. It is interesting to note that 
Hawkins and Harvey conclude that mechanical jjuncture is the method by 
which Pythium debaryanum passes after entry through the ordinary cell- 
walls of the potato tuber,^^ and that resistance of the tuber cells to 

11 Blackman and Welsford : ' Infection by Botrytis cinerea.' Annals of Botany, xxx., 
389, 1916. 

1^ This suggestion that such molecular forces come into play was originally put 
forward in a discussion by Dr. A. L. Balls. 

1' L. A. Hawkins and R. B. Harvey : ' Physiological Study of the Parasitism of 
Pythium debaryanum Hesse, on the Potato Tuber.' J. Agric. Res., XVIIL, 275. 1919. 

K.— BOTANY. 241 

mechanical puncture and resistance to attack by this fungus are definitely 
correlated. These authors also determined by plasmolysis the osmotic 
pressure of the fungal hypha and the pressure required to perforate the 
tissues, and they found that in all cases but one the osmotic pressure 
was sufficient to allow of puncture of the wall of the potato cell by the hypha. 

The question of the nutritive conditions to which the germ-tube is 
exposed when developing on the host tissue is evidently of importance in 
infection. A strong well-developed germ-tube is more likely to succeed 
in penetrating the host tissues than a weakly one. This is in agreement 
with the experience that with forms like Botrytis and Colletotrichum it is 
easier to get infection from drops of weak culture medium than from water. 
In nature, however, the ' infection drop ' must usually consist of rain or 
dew. That substances which are able to stimulate the growth of the 
germ-tubes can diffuse from the underlying host tissue into the infection 
drop has been shown by W. Brown [loc. cit. 1916). How considerable 
may be the amount of substances diffusing into water on the surface of a 
plant is shown by the analysis of dew from cotton plants given by Smith. 
No less a quantity than 1,300 c.c. was collected, and it was found to have 
a content of total solids of 1,023 parts per million, most of the solids 
consisting of calcium and magnesium carbonates.^* 

The observations of R. J. Noble on Flag Smut of wheat {Urocystis 
tritici) provide another example of the stimulating action of minute 
amounts of tissue extracts. The addition of a few thin slices of wheat 
tissue to water in which well-soaked spores of this fungus are lying increases 
very markedly the amount of germination over that in ordinary culture 
media. The action is not specific, for tissues of rye, barley, flax, etc., 
will produce the same effect, though to a less degree. The distillate from 
watery extracts of wheat seedlings was also found to act, so the stimulating 
substance is volatile, and possibly similar to the substances observed by 
Brown, to which reference has already been made.^^ 

It is clear from such observations as these that the conidium may find 
in the infection drop on the leaf a supply of nutritive or stimulating 
substances. Of the chemotropic power of these substances there may be 
some doubt, but of their importance in the production of vigorous germ- 
tubes well equipped for the work of cell-wall penetration there can be 
little question. In the study of the mechanism of entry by various fungi 
into the epidermal tissues of their host undertaken by the writers already 
mentioned, not only was there no evidence of solution of the cuticle, but 
until the cuticle had been ruptured there was no sign of enzymatic action 
on the cell-wall layers beneath. This suggests that cell-wall dissolving 
enzymes are unable to diffuse through the cuticle. It should be pointed 
out, however, that Smith,i* in his study of the haustoria of the Erysiphacese, 
describes a change in the staining reaction of the cell wall below a hypha 
before the cuticle had been ruptured. Miss Allen also describes a marked 

1* C. M. Smith : ' Excretion from Leaves as a Factor in Arsenical Injury.' J. Agric. 
Res., XXVI., 191-4, 1923. The analysis in full, in parts per million, was S1O2, 13 ; oxides 
of Iron and Aluminium, 17 ; SO3, 26 ; CI, 19 ; CaO, 529 ; MgO, 100 : CO (by titration), 

^' R. J. Noble : ' Studies on Urocystis tritici Koern, the Organism causing Flag 
Smut of Wheat.' Phytopathology, 13, 127, 1923. 

'* G. Smith : ' A Study of the Haustoria of the Erysiphaceae.' Bot. Gaz., 16, 1905. 

1924 R 


change in the cell walls of the guaid cells lying below the appressorium of 
P. gramiiiis trilici. These guard cells had not been penetrated, the hypha 
passing between them to form the substoraatal vesicle, and yet the walls 
of these cells became markedly altered in their reaction to stains. It may 
be that both these cases demonstrate the action of enzymes derived from 
the fungus, for diffusibility and uon-diffusibility are only questions of 
degree ; it may be, on the other hand, that these cell-wall changes are due 
to changes produced in the host cell as a result of the entry into the cell of 
poisonous fungal products more diffusible than are enzymes. 

The question may now be considered as to what progress has been made 
by plant pathologists in elucidating the quality of natural immunity. As 
has already been stated, the problem of natural immunity is an extremely 
difficult one which animal pathologists on their side have found very 
baffling. It can be said, however, that some success has been achieved 
in a preliminary analysis of some cases of natural disease resistance 
in plants. As is so common in biological work, the difficulty of solution 
is greatly enhanced by the variety in the types of disease resistance. In 
many cases resistance to disease is achieved by keeping the enemy oat by 
some physical barrier, or possibly by some special chemical environment 
in the abseiKie of such a barrier. In other cases the parasite achieves 
entry and in a susceptible host makes its way through the tissues 
comparatively unimpeded, while in a resistant the entry calls forth a 
wound reaction leading to the production of cork which hinders or 
sets a complete bar to the progress of the invader. A good example 
of these two types of behaviour is that of Fusarium Lini when 
attacking susceptible or resistant forms of flax. In one case the physio- 
logical processes of the resistant host interacting with those of the fungus 
lead to abundant cork-formation ; in the other they do not. In what 
manner the physiological processes of the two types of host difier we 
cannot at present say. Nor can we at present explain why the harmonious 
relationship, which in the case of the cereal Smuts is established for most 
of the vegetative life of the host, suddenly breaks down on the development 
of the inflorescence. Is the metabolism of the cells of the developing 
reproductive organs so markedly different from that of the meristematic 
cells that the fungus is stimulated into active development and parasitism ? 
It would seem likely that a further knowledge of the nature of the 
' physiological gradients ' between the parts of plants would throw some 
light ujjon the peculiar relations of host and parasite in the cereal Smuts. 
How elusive may be the factors underlying resistance is exemplified 
by the observations of Walker ^^ on Onion Smudge due to Colletotrichum 
circinans. He found that onion bulbs with coloured outer scales were 
usually highly resistant, while white varieties were in general susceptible, 
and, furthermore, a watery extract of dry outer scales of the coloured 
onions is a marked toxic to the spores and mycelium of the fungus. On 
further examination it was found that although the internal white scales 
can be infected with ease, yet an extract of these inhibits the germination 
of the conidia and also retards the development of the mycelium. The 
volatile ' onion oil ' seems responsible for the inhibition and retardation, 
yet when the fungus is growing in the host tissue there is no such action. 

" J. C. Walker ; ' Disease Resistance to Onion Smudge.' J. Aqric. Res., XXIV., 
1019, 1923. 

K.— BOTANY. 243 

It is only in the Erysiphaceaj and Uredine89 that we have knowledge 
of any cell reactions (though not of any general reaction of the plant body) 
comparable with those occurring in the infectious diseases of the higher 
animals. In these two groups the phenomenon of so-called specialisa- 
tion of parasitism is well marked, and it is a comparative study of the 
behaviour of the biologic forms of the parasite on susceptible and resistant 
hosts that has been most fruitful. As has been known for some time, the 
normal relation of host and parasite in the mildews and rusts is, in the 
early stages of infection, one in which the fungus develops at the expense of 
the host cells ; these, however, are not killed but stimulated to active de- 
velopment. De Bary observed long ago that the mildewed leaf may retain 
its green colour longer than the uninfected one. Salmon observed some 
years ago that the conidia of Ery.siphagramims-when growing on other than 
their normal host might send down haustoria into the epidermal cells, but 
such absorbing organs were short-lived. Neger^' has recently investigated 
more closely the result of sowing upon the leaves of Hieracium of the 
conidia of E. Cichoracearum from Sonchus asper. The germ-tubes send 
into the epidermal cells outgrowths which start to produce haustoria. 
In contrast with infection of the normal host, the cells react markedly ; 
they become filled with a gum- like mass which encapsules the haustoria. 
The epidermal cells then lose their turgor, die, and the development of 
the fungus is stayed. A leaf sprayed with suspension of such conidia 
appears as if it had been sjwinkled with minute drops of a corrosive fluid. 
However, it is in relation to the cereal rusts that we have the clearest 
picture — in its purely superficial aspects at least — of the nature of resist- 
ance. With the discovery by Professor Biffen that resistance to the attack 
of Puccinia glumanim was associated with a single Mendelian factor, atten- 
tion was naturally turned to the question of the nature of this resistance. 
Miss Marryat, comparing in Professor Biffen's laboratory the susceptible 
Einkorn and the resistant Michigan Bronze wheats, made the surprising 
discovery that the resistance was in one sense no resistance at all.^' 

The variety Einkorn was not able to keep the parasite out, for the 
hyphse attacked the mesophyll cells, but the invaded leaf-cells — instead 
of establishing an harmonious working relationship with the mycelium 
as with Michigan Bronze — react very strongly, witli the result that both 
they and the invading hyphae are killed. The course of infection is thus 
stayed as a result of this hjjyersensitiveness of the host. The result with 
P. glumarum was later extended to P. graminis. The striking and assiduous 
work of Stakman and his co-workers has revealed to us that even 
P. graminis forma tritici consists of twenty or thirty different strains with a 
widely varying range of susceptibility and resistance among the different 
varieties of wheats. Stakman * in 1915 was able to confirm the violence 
of the reaction when strains of this form are sown on a resistant 
host ; hypersensitiveness here also is the key to resistance. Last year 

" F. W. Neger : ' Mehltaupilze — eine Art von gedultete Svmbiose.' Flora, CXVI., 
331, 1923. 

■"'' D. C. E. Marryat : • Notes on the Infection and Histology of Two Wheats immune 
to the Attack of Puccinia glumarum.'' J. Agric. Science, II., 129, 1907. 

* E. C. Stakman : ' Relation between Puccinia graminis and Plants highly 
resistant to its attack.' J. Agric. Bes., V., 193, 1915. 



Miss Allen ^^ published a very careful and detailed cytological study of the 
infection of susceptible and immune wheats by forms III. and XIX. of 
P. graminis tritici. Mindum wheat is immune to form III. and Kanred 
to form XIX., so the behaviour of these two wheats was compared with 
that of other susceptible varieties. When Mindum is infected with the 
uredospores of form III. an appressorium is formed over the guard cells 
and entry occurs in the normal way through the stoma. Usually the first 
haustorium from the infection hypha develops in a mesophyll cell and its 
formation is the signal for a violent reaction on the part of this cell. The 
host-cell contents, including the cytoplasm, nucleus and plastids, flow 
rapidly towards the haustorium and become massed around it, forming 
apparently a sheath to the haustorium. Of the haustorium and host-cell 
cytoplasm Miss Allen states ' each seems to be toxic to the other ; at least, 
both die very soon.' The haustorium and its cytoplasmic sheath appear 
to be partially digested. The infection hypha is not killed by this reaction 
to the first formed haustorium, but only checked ; it may develop a few 
other haustoria in other host cells which are similarly killed ; finally the 
limited resources of the hypha are exhausted and it succumbs. 

From a single infection only a small number of cells, about five or six, 
are killed by being entered directly by the fungus. The ' fleck ' visible to 
the naked eye which is the sign of an attack successfully repelled consists 
of a much larger number of dead or damaged cells. This is explained by 
the fact that the violent primary effect due to entry is followed by a mild 
secondary effect on the cells surrounding the area of cells killed by entry. 
These neighbouring cells in a region 3-4 cells deep become plasmolysed 
and shrunken, and some of them show marked swelling of the walls. 

Although in the cereal rusts we have the most complex reaction to 
attack by an invading organism which has been observed in plants, we find 
very few phenomena analogous with the response to infectious disease of 
higher animals. When the susceptible forms are attacked we find no 
spontaneous cure, no recovery of the attacked cells. We have no evidence 
in the resistant forms of the productions of antibodies in either the suscep- 
tible or resistant forms ; the death of the haustoria may be simply due to 
the death of the host cells in which they lie. It is true that we have a 
digestion of the haustorium, but this ' phagocytosis ' — since the digestion 
of the haustorium is associated with the digestion of the host-cell con- 
tents and takes place after the death of that host cell — may be nothing 
more than an effect of autolysis. ^^ Again, no general bodily reaction 
of the plant is apparent, each infection is highly localised, and each group of 
host cells fights a solitary battle independent of its neighbours. No analy- 
sis of plant resistance on the lines found so successful in animal disease 
can be achieved at present, nor is it likely in the future in view of the 

"' R. F. Allen : ' Cytological Studies of Infection of Baart, Kanred and Mindum 
Wheats by Puccinia graminis tritici.'' J. Agric. Res., XXVI., 571, 1923. 

^' It is true that in such peculiar symbiotic relationships as those of the orchid 
fungus and endotrophic mycorhiza — cases which do not fall into the category of ordinary 
disease — we do find digestion of invading fungal hyphas by living active host cells. 
Such cells are, however, far from acquiring any resistance by such phagocytosis, for it 
has been observed both in orchids and in mycorhiza that host cells which have success- 
fully coped with one attack by the process of digestion may be invaded again (vide 
Rivett, Annals of Bot.. XXXVIII., 1924). 

K.— BOTANY. 245 

marked dissimilarities between the two. As has already been insisted 
upon, the immunity which has to be explained in plants is natural, while 
that resistance which animal pathologists have explained, at least in part, 
is acquired. The explanation of the difference in the behaviour of the 
mesophyll cells of the susceirtible and resistant wheat must lie in the 
difference in the normal physiological processes of the two. This demon- 
strates how dependent is plant pathology for its advance on plant physio- 
logy. The differences do not seem to be merely differences specific to 
the wheat varieties, differences such as would be common to all the cells 
of the plant — or if there are such differences they are easily masked by 
other factors— for Miss Allen observed that while the mesophyll cells of 
the resistant wheat reacted violently when invaded, yet if an epidermal 
cell was attacked the haustorium developed might attain its full size and 
function for some time. It is evident that we must await fuller knowledge 
of the normal physiological processes of the cells of the two varieties, and 
of the physiological differences between the cells of different tissues, before 
much light will be thrown on the nature of such immunity as is met with 
in the Erysiphacese and Uredinese. 

A consideration of the nature of disease resistance in plants thus leaves 
us with no expectation of finding means for endowing plants with artificial 
disease resistance. Apart from the protection of plants from infection 
by the use of fungicides, etc., our chief hope of combating disease lies in 
two directions — one, that of breeding disease-resistant forms of plants, and 
the other that of the enhancement of the natural resistance of the plant. 
In breeding for disease resistance, marked successes have been obtained 
since Biffen's fundamental work on Mendelian inheritance of resistance to 
Puccinia glumarum. In a number of cases of rust resistance in cereals 
since examined, immunity has been found to be dominant over sus- 
ceptibility. The question of breeding wheats resistant to P. graminis, 
which is, of course, one of great economic importance, has been much 
complicated by the discovery, to which reference has already been made, 
that a very large number of biologic forms or strains of P. graminis tritid 
exist ; high resistance to attack by some of the strain may be associated 
with marked susceptibility to attack by other strains. Aamodt, however, 
claims to have demonstrated that it is possible to build up synthetically 
a wheat which will be resistant to a large number of biologic forms of 
P. graminis tritid. ^^ 

Although we find that the field of control of plant diseases by substances 
lethal to fungi and by the breeding of disease-resistant host plants is being 
actively cultivated at the present time, yet the field of inquiry as to the 
effect of environment on the liability of plants to diseases is comparatively 
unworked. The view that immune plants, such as cereals immune to rust, 
might suddenly lose their resistance under new conditions is now no longer 
held ; the apparent loss of resistance is probably in part explicable by the 
fact that the host in its new environment has been subjected to attack by 
another biologic form of the fungus than that to which it is resistant. In 
spite of this, however, it is perfectly clear that with numerous diseases the 
degree of natural resistance is markedly affected by the conditions of 

" 0. S. Aamodt : ' The Inheritance of Growth Habit and Resistance to Stem Rust 
in a Cross between Two Varieties of Common Wheat. ' J. Agric. Bes., XXIV., 457, 1923. 


cultivation. In some classes of disease, such as the Rusts, the intensity 
of attack tends to rise with the increased vigour of the plant, and Melhus ^* 
found that with unhealthy plants it was almost impossible to obtain 
satisfactory infection by Cystopus candidus. 

On the other hand, there is a large class of infectious diseases in which 
the degree of natural resistance can be markedly enhanced by good 
cultivation. Under good conditions such diseases, which with Nowell ^^ 
may be termed ' Debility diseases,' are of little importance ; they only 
become serious when the crops are growing under unfavourable conditions. 
Diseases of this class are usually caused by saprophytes which are only 
weakly parasitic. The question of the nature of the changes occurring in 
the plant in conditions of so-called debility are quite unknown. The 
problem is sure to be a complex one, but it is possible that one of the 
factors may be an increased permeability of the superficial tissues of the 
less vigorous plants, so that the spores on the surface of the host find 
conditions especially favourable for vigorous growth. In addition to the 
relation of general health to the incidence of certain plant diseases, we 
have the undoubted effect of certain fertilisers, such as potash, in reducing 
the intensity of fungal attack. Exploration of such fields of physiological 
research, though no doubt the difficulties of investigation are considerable, 
should certainly provide results of great scientific interest. A clue to the 
nature of the changes occurring in plants which can reduce their liability 
to disease may also open the way to the enhancement of natural 
resistance by other and possibly more economical ways. Clearly it is on 
plant physiology that plant pathology is largely dependent, not only for 
the elucidation of the relationship of host and parasite, but also for 
fundamental scientific knowledge which may profoundly affect economic 

** J. E. Melhus : ' Experiments on Spore Germination and Infection in certain 
Species of Oomycetes.' Wisconsin Agr. Exp. Stat. BvlL, 15, 1911. 
^' Nowell : 'Diseases of Crop Plants in the Lesser Antilles.' 1923. 








Freedom, in that sphere of politics in which we use the word most often, 
may be an attribute either of the individual, in his thought and action 
within the community, or of the community itself, in its relations and stand- 
ing among other communities. It may be a right of the citizen, or it may 
be an attribute of the State. In the intellectual sphere, with which we 
are here concerned, freedom may similarly be an attribute either of the 
individual teacher, in his teaching and speaking and writing, or of the 
whole academic community, in its relation to the general environment 
of political authorities and economic interests in which it is set. These two 
freedoms of the mind are almost correlative. We may almost say that a 
free professoriate means a free academic community ; and, conversely, that 
a free academic community means a free professoriate. But there are quali- 
fications and limitations of this identity. A university which is free from 
control by the general social environment may seek to control unduly its 
own professors in the name of its own alleged freedom. We cannot, after 
all, treat academic freedom under a single head ; and in any discussion of 
the subject we must distinguish the freedom of the teacher from that of 
the university. 

The freedom of the teacher, like all freedom that is other than mere 
license and anarchy, must exist within a framework of law, because it 
exists within the framework of an institution, and because, again, any 
institution involves some system of law. The law of an academic institu- 
tion is partly an unwritten code of professional conduct, and partly, it 
may be, a written set of principles and tenets. The unwritten code forbids 
a teacher to use his class-room as a place for the inculcation of partisan 
views. It may be difficult to draw a clear line of division between what 
is partisan and what is impartial ; but we should all agree that there is a 
line, and that, in his class-room, a professor is not free to wander on the 
further side of that line. What he may do outside the class-room is another 
matter, which we must consider later. A written set of tenets and prin- 
ciples is comparatively rare ; but it may obviously exist, for example in a 
theological college or a general college founded on a confessional basis. A 
professor who has subscribed to these tenets has voluntarily limited his 
freedom by that subscription. The college to which I belong at one time 
required a written subscription from its teachers to the Thirty-nine Articles. 


When F. D. Maurice was deprived of his chair, in 1853, for his views on 
eternal punishment, it was not definitely stated in the resolution of the 
governing body that he had contravened those Articles. It was stated, in 
vaguer terms, that his opinions were ' of dangerous tendency . . . calculated 
to unsettle the minds of the theological students . . . detrimental to the 
usefulness of the college.' None the less, though the action taken by the 
governing body was not grounded, and perhaps could not have been 
grounded, on a definite contravention of the Thirfcy-nine Articles, the 
existence of a rule of subscription to those Articles was the real basis of 
that action. 

A much more difl&cult question arises when we turn to consider the 
action of a professor outside his class-room. Here, again, the case of 
F. D. Maurice occurs to the mind. He was attacked in 1851, and virtually 
censured, though not deprived of his chair, for his connection with the 
Christian Socialist movement. The case is curiously typical, and curiously 
apposite to our modern difficulties, even though it occurred over seventy 
years ago. Croker had launched the attack in the Press, and besides attack- 
ing Maurice he had drawn the college into the issue, by stating that 'it added 
to his surprise to find the holder of such views occupying the professorial 
chair ... in King's College, London.' Some general considerations of a 
large pertinence are suggested by Croker's action and words. The Press 
may defend, and by its own position as a natural champion of freedom of 
expression of opinion it will often actually defend, the freedom of a pro- 
fessor ; but just because it is necessarily set on publicity, it is also a danger 
to that freedom. It does not help the free course of thought that its 
delicate difficulties should be cried in the streets. The Press, again, will 
always attach the label ' professor,' and the name of his institution, when 
it chances to mention in any connection an ordinary citizen who is also a 
professor at any institution. By such attachment a sad result is entailed. 
If the citizen who is also a professor speaks on a public issue, he is made to 
involve his institution in what he says. If what he says is unpopular, he 
may make his institution unpopular : it may lose students : it may lose 
benefactions. 1 What is the institution to do ? Should it make a rule, 
such as the Principal of King's College seemed to suggest in 1851, ' that 
you will do your utmost to bear in mind the duty and importance of not 
compromising the College ' ? If it makes such a rule, it will be bound to 
define what is compromising, and it will be bound in the last resort to 
enforce its definition. In order to prevent itself from being compromised, 
it will compromise itself terribly. A professor may compromise it in part : 
it will compromise itself as a whole. A wise president of a great American 
University — President Lowell of Harvard — has put the point admirably in 
his annual report for the Session 1916-1917 : ' If a University or College 
censors what its professors may say ... it thereby assumes responsibility 
for that which it permits them to say. This is logical and inevitable, but 
it is a responsibility which an institution of learning would be very unwise 
in assuming.' A wise university will run any risk of being compromised 
by its members rather than compromise its entire self. 

But if the university is wise to tolerate, the professor is wise to be 
severely moderate and master of himself. It is true that he is a citizen, 

' This is stated, or implied, by the Principal and Council of King's College in 
1851. See the Life of F. D. Maurice, by F. Maurice, ii., p. 80, p. 98, p. 101. 


and has every right of an ordinary citizen — engineer, lawyer, doctor or 
banker — to express his opinions on civic affairs. It may even be urged 
that he has a special right to express himself, in virtue of the possession of 
special knowledge ; and it is possible to contend that he has even a duty 
to aid the judgment of the community by contributing his knowledge and 
his opinion in vexed questions which lie specially within the ambit of his 
chair. A professor of Spanish, for example, may hold himself bound to 
instruct the public opinion of his community on Spanish affairs, and even 
to suggest the adoption of a definite attitude by his fellow-countrymen in 
relation to such affairs, if they have become the question of the hour, 
pregnant with issues of peace or war, and if he has a knowledge which has 
not yet been attained by publicists, journalists, and other such guides of 
public thought. On the other hand, it is a pity that a professor should 
become a publicist except in the gravest emergency. It is difficult to be 
at once a publicist and a scholar ; and a professor is primarily a scholar. 
Here we touch a fundamental consideration. A professor is a citizen, 
with the general rights or obligations of a citizen : he is also a member of a 
profession, with the special obligations of that profession. Herein he is 
like the doctor or lawyer, who have also their special obligations, as, for 
example, the obligation of secrecy in regard to the affairs of their clients. 
The special obligations of the professor, which are contained in the unwritten 
code of which we have already spoken, are less definite than those of the 
doctor or lawyer ; but they are there. He has embraced a profession 
devoted to the dispassionate search for pure truth. He seeks truth for 
truth's sake by a rigorous method of inquiry. The temper of his mind 
must be steeled into a resolute disposition to see every side and to weigh 
every factor. He is training young minds : what he is, and what he does, 
affects the growth of those minds, just because the attitude, the temper and 
the method of the teacher are always a suggestive force to the young, and 
are always, however unconsciously, in virtue of that law of imitation which 
sways so strongly all our minds, the fountain and source of a like attitude, 
temper and method among the taught. If there is a discipline which is a 
special obhgation of the soldier, there is also a discipline which is a special 
obligation of the professor who serves under the banner of truth. To see, 
and to show to others, the six sides of a square question : to amass every 
relevant fact, and to leave no fact unverified : to shun the limelight of 
pubUcity, because it distorts and is not the clear light of truth : not to lend 
knowledge to the service of a one-sided cause, or to divulge research in 
aid of a journalistic ' scoop ' — all these are parts of the discipline. At 
the same time, the professor must be a man, and not an automaton. He may 
become the latter, if he is purely and solely of the laboratory. Some 
measure of outside interest and outside work is a condition of vitality and 
even of balance. Without it he may be ansemically academic, and lose 
himself in an exaggerated sense of the sovereignty of his subject. F. D. 
Maurice was not in error when he said of his colleagues that ' their classes 
in the college, I believe, are infinitely the better for their labours and 
studies out of it.' ^ 

There are certain subjects in which the freedom and the duty of a 
professor raise specially difficult problems. They are the subjects of 
history, government and economics — to which we may perhaps add the 

2 Op. cH., ii., p. 85. 


subject of modern languages, wlien the professor of such a subject concerns 
himself, as it is good that he should, not only with the language and 
literature but also with the history and contemporary civilisation of the 
nation with which he is concerned. If the cause of academic freedom was 
fought in the past on the ecclesiastical field, and in regard to chairs of 
divinity, it is likely to be fought in the future on the field of politics and 
economics, and in regard to the chairs which touch those subjects. A 
professor of such subj ects cannot stop short of running into the actualities 
of the present. If he were required to do so, he would be stopped from 
reaching what we may almost call the point of fertilisation, where his 
knowledge touches actual life. I would not say that the history of the past 
is the guide to the solution of the problems of the present ; I would rather 
say, with Croce, that all history is contemporary history, and that the 
historian explains what we are by showing to us the living past which 
makes our present life. Even on that basis, the present is the concern of 
the historian, as it is also, for that matter, of the teacher of political theory, 
or of economics, or of modern languages. The teachers of all these subjects 
are handling and interpreting the present. They move in a region of very 
special difficulty and very special obligation. They handle the live stufi 
of which actual political and economic questions, national and international, 
are made. I^tcedunt per ignes. They may write to the Times on current 
questions, according to our English habit, which has no doubt its American 
equivalent ; they may publish pamphlets and books on current questions ; 
they may even (and this raises desperate difficulties) become parliamentary 
candidates. I cannot deprecate the trend of these subjects and of their 
teachers in modern universities towards what I may call actuality. At 
the same time, I cannot but register the difficulties to which it leads. 
Public attention may be drawn to a university which has become a live 
coal, and public criticism may fasten on its burning. What is more, a 
number of interests may interest themselves in controlUng the manner of its 
burning. Universities are always in need of endowment. A benefactor, or a 
group of benefactors, may be very ready to found a chair — and that possibly 
a chair of a certain complexion — in a subject of history, or of politics, or 
of economics, or of the language, literature and civihsation of a given nation. 
If the professor is conformable to their expectations, all may be well — 
from one point of view. If he is not — surgit quaestio. But this difficulty 
belongs rather to the topic of the freedom of the whole academic community, 
and that belongs to another and later inquiry. Here we are concerned 
with the freedom of the individual professor. So far as that freedom is 
concerned, I can only repeat, with some qualification and extension, the 
conclusions I have already tried to state. My general principle is freedom, 
uncontrolled by any assumption of responsibility by the university, which 
is likely to run more danger thereby than can ever be involved in any 
possible indiscretion which a professor may commit in the use of such 
freedom. My quaUfication of that principle is two-fold. In the first place, the 
freedom of the professor is subject to the discipline of the profession, 
which commands him to seek the truth, the whole truth, and nothing 
but the truth. If he cannot submit himself with all his heart to that 
discipline, he had better quit the profession and become a politician or a 
journalist. In the second place, the freedom of the professor, while it is 
not subject to the control of the institution to which he belongs, must 


at any rate be qualified by the duties inherent in his membership of that 
institution. If it gives him freedom, he must not give it obloquy in return. 
He will be wise, in many cases, to say, and to say very clearly, that he speaks 
in hisown name, as a private citizen, without any warrantfromhis institution, 
or any power to bind or conclude his institution in any way by what he says. 
But I do not think that a professor will ever go far wrong if he submits 
himself to the discipline of the profession. The great safeguard of true 
professorial liberty is simply a stern sense of the sanctity of the academic 
vocation, cherished among all its members, and enforced by all its members 
through the sanction of disapproval against an erring colleague. What we 
need is the elaboration by the professors themselves, and the enforcement 
by the professors themselves, of a code of professional conduct. Here at 
any rate, without any subscription to the tenets of guild socialism, and 
without any confession to a creed of the government of the teaching 
profession by itself, one may see a field for professional self-determination. 
It is not exactly an easy thing. Some professors, of a conservative cast 
of mind, will always frown upon their colleagues who are hardier, even 
when they walk within just limits. Others, of more radical propensities, 
will always smile upon a bold colleague, even when he has obviously over- 
shot any conceivable mark. But if the thing be difficult, it is none the less 

I turn to consider, in conclusion, the broader theme of the freedom of 
the whole academic community. The mediaeval university, as its very 
name implies, was a free guild of teachers, or sometimes of teachers and 
scholars. It was not subject to any local authorities (there were none, and 
anyhow it was not local) ; it was hardly subject to the State, for the State 
was a loose federal sort of body, which left all guilds pretty much to their 
own devices ; it might be subject to the Pope, because its members were 
clerks, but it could be turbulently indej^endent even in the face of the 
Pope. There were benefactors — munificent benefactors — who founded great 
colleges within the universities ; but though they were fond of making 
statutes for the government of their colleges, they left opinion alone, for 
the simple reason that there was no need for any sort of control. The 
curriculum was largely a traditional curriculum in the arts ; and if theology 
was sometimes fertile of heresies, there was, at any rate, only a single 
Catholic Church, and all men were members of one communion. The 
modern university is set in a far more tangled web of environment. It is an 
object of lively interest to the State, which may sometimes exert, or seek 
to exert, a control of its teachers and its teaching, and may at any rate 
(I speak of Great Britain) appoint Royal Commissions to inspect and 
statutory commissions to reform its organisation. Local authorities — 
a dominion in Canada ; a county or city in England — may interest them- 
selves deeply in what they regard as a local university. Benefactions and 
endowments from private sources may play a large part in determining the 
extent and the direction of university development. A Labour party may 
demand that the universities shall undertake extra-mural work among the 
working classes ; an organisation such as our National Union of Teachers 
may ask that the universities shall make it their policy to accept and train 
as graduates all the members of the teaching profession in the country. 
What has become of the free guild of the Middle Ages ? And should the 
free guild of the Middle Ages be our modern ideal ? 


No modern university can have anything of the freedom of a mediaeval 
university. The mediaeval university stood alone ; the modern university 
is part of a great educational system which embraces the whole community. 
It cannot control the lower ranges of this system — the elementary and 
secondary schools — or demand that the work done in those ranges shall 
be simply preparatory to its own work as conceived and determined by 
itself ; for a majority of the students in the lower ranges will never come to 
the universities, and their studies must be organised as ends in themselves, 
and not as means or propaedeutics to work in the university. The 
university has to adjust itself to the educational system, and not the 
educational system to itself. That educational system is the result of a 
social ideal, and that social ideal is in the last resort defined by Parliament. 
The university is therefore bound to conform to the social ideal adopted 
by Parliament and expressed in the educational system. It has the one 
consolation of hoping that by its thinking and teaching it is a great force 
in forming the social ideal by which it is itself controlled. In English- 
speaking countries, at any rate, the final authority of the State is not 
an enemy to the freedom of the university. A much more dangerous 
enemy is social interests, especially when they are backed by the power 
of cash. We may not believe in more than f of the argument of The 
Goose Step, in winch Mr. Upton Sinclair draws his lurid picture of the 
bogey of social interests. But even with a discount of f , or more, he is 

It is a saying current in universities — and, I dare say, everywhere else— 
that finance determines policy. It is certainly true that the methods by 
which a university secures its revenue cannot be without effect on the 
freedom with which it develops its policy of education. In no university 
—not even in Oxford and Cambridge — does the student pay the whole, 
or anything like the whole, of the cost of his education. In the newer 
English universities we may say that, on the average, the student provides 
x^g of the cost of the running of his university. The remaining ^-^ has 
to be found from other sources. Before we look at those other sources, we 
may venture on a general observation. The persons or bodies who provide 
the required ^^ may be inspired by a variety of motives. We may put 
first the motive of advancing the cause of truth and promoting the higher 
education of the best minds of the community. But we must allow for 
the entry of other motives. A university is, we may say, a great pulpit ; 
and there will also be some who desire to ' tune the pulpits,' and to make 
the preachers say acceptable things. ' It is another current saying that 
those who j^ay the piper call the tune. We should be shutting our eyes 
to a genuine danger if we did not admit the possibility of ' tuning.' And 
if we regard it as an undesirable possibility, we must be ready with sugges- 
tions for its avoidance or, at any rate, its diminution. 

There are three possible sources of university revenues. One is the 
fees of students : a second is private benefaction ; a third is public assist- 
ance, whether from the national or the local authority. It is a desirable 
thing that universities should continue to draw an income from the fees 
of their students. It is earned income : it is independent money. It 
is good both for the university and its student, making the one feel that it 
earns as well as spends, and the other that he gives as well as receives. 
It is indeed a pity that any system of fees should exclude a single student 


of promise from a university. But a proper system of national and local 
scholarships (which should include maintenance, where it is necessary, as 
well as fees) will prevent any such exclusion. Granted, therefore, such a 
system of scholarships, there seems to be every reason for maintaining 
university fees which provide from y% to f of the income of a university. 
They help to give the university self-respect and independence : they may 
help to give the same qualities to students. 

The second source of income, which takes the form of private benefac- 
tion, has its fine and attractive side. When one listens, in the bidding 
prayers of the old English universities, to the names of the benefactors of 
dead and bygone centuries, one cannot but be proud of a great tradition 
long and truly maintained. And again, when one thinks of the paucity of 
private benefaction to universities in England to-day, and contrasts the 
abounding munificence of many cheerful givers in the United States, one 
cannot but feel abashed. Yet there is some reason for feeling that, in 
modern democratic communities, there is a limit to the extent to which 
private benefaction can safely endow universities. Universities are 
great public institutions. They belong to the general commonwealth. 
They cannot be proprietary. They cannot be sectarian. They must 
be above even the suspicion of belonging to one or other side in our social 
cleavage. They belong to both. A university which relies to any great 
extent on private benefaction may tend, however unconsciously, to teach 
and to preach acceptable things ; and that is the greatest offence which 
it can commit against the spirit of truth. To take benefaction if it comes, 
but not to go out to seek it ; to look even a gift-horse in the mouth with a 
modest and discreet inquiry ; to be sure that no endowment contravenes 
by one jot or tittle freedom of inquiry or freedom of expression — these are 
the natural policies of a university which respects its own genius of academic 
freedom. I would not exaggerate the dangers of private benefaction to 
universities. Often and often it is the fruit of plain and unconditioned 
generosity. But I would not be blind to the possible dangers. And it 
is always possible that private benefactions may have their tacit implica- 
tions — a form of capitalism ; a particular kind of nationalism ; some brand 
of confessionahsm — which may make them enemies of academic freedom. 

I come, in conclusion, to the third source of university revenue, which 
is that of public assistance from the local or national authority. If our 
universities are truly great public institutions, subject (as they are in 
England) to visitation by the State and to reformation by the State, they 
must be a charge on the public revenues for that part of their expenditure 
which they cannot earn by fees from their students or receive in gifts from 
private endowments. In our English system the aid given to education 
from public funds (whether the education be elementary, or secondary, 
or university) is always two-fold. Part comes from the local authority — 
the county or borough council : part comes from the national exchequer. 
The two co-operate : they bargain, and often dispute, about their respec- 
tive shares. Sometimes education suft"ers from their disputes ; but in 
many ways (and not least in universities) it gains from the presence and 
joint action of the two authorities. The national authority may stimulate 
a local authority to increase its contribution ; the local authority may 
attach conditions to its contributions which keep the national authority 
within due limits of action. There is a certain gain in the system of check 


and counter-check between local and national authorities. It is more 
favourable to universities than a system in which there is only a single 
public authority. It is sometimes a little of a trouble (and in a moment 
of irritation one might even describe it as a nuisance) that both authorities 
are apt to crave information about the same point on different schedules. 
But the gain is much greater than the loss. 

The aid which is given by the national authority to universities in 
Great Britain is at the present time much greater than that which is given 
by the local authority." And it is given on a singularly liberal scheme. 
An annual sum of £1,250,000 is distributed by a Treasury Committee of 
independent scholars among the universities in the shape of block grants, 
which each university is free to spend along the lines of its own policy. 
Only in the sphere of medical education, and in respect of the grants made 
to medical schools, has any specific educational condition been attached. 
Here the policy of favouring the system of clinical units has been adopted 
by the Committee, and that policy has its critics. That, however, is the 
only action which even smacks of interference. The aid given by local 
authorities is hardly given on so liberal a scheme. Local authorities are apt 
to regard universities as their own local institutions which they should control 
to a greater or less degree ; and they sometimes allocate their aid to specific 
purposes only, or attach very definite conditions to their grants. So long 
as their grants are definitely less than those of the national authority, and 
so long as there is the dualism of the local and the national authorities, 
no serious alarm need be felt. At the same time one cannot but feel that 
the local authorities are inclined to press too far the idea that ' democratic 
control ' of university education means its control by elected local repre- 
sentatives assembled in county or borough council. We may rejoin that 
democratic control of a university is control by its own governing body, 
provided that that body is democratically constituted, and is duly subject 
in serious matters to public criticism. And the Treasury Committee, which 
virtually proceeds on that conception, seems closest to genuine democratic 

On the whole, there is no serious menace to academic freedom in Great 
Britain from a system of university finance which relies, as our system does, 
on a balanced mixture of income from fees, public assistance, and private 
benefaction, with the balance perhaps inclining more and more to a prepon- 
derance of public assistance. Much, however, depends on the dualism of 
our system of public assistance, and much too on our habit of leaving 
institutions alone, to go their own way, as far as possible. The present 
position is very tolerably good, and the general English notion of self- 
government leaves our universities as free as it is good for them to be. 
There might conceivably arise a government, strongly wedded to definite 
principles, which refused to give aid to universities unless those principles 
were taught, or were not, at any rate, neglected in the instruction given by 
the universities. An advanced Labour Government, for instance, might 
possibly take objection to the teaching by a university of what, in its 
view, were ' capitalistic ' economics, and the omission of the economics of 
Socialism. But the possibility is most exceedingly improbable — unless 

^ In England and Wale.s, during the academic year 1922-1923, the percentage of 
the total income of universities due to grants from Parliament was 38*1 : that of 
tot£|.l income ^.rising from grants made by local authorities was 14'4, 


the professors of economics are exceedingly injudicious. We may safely 
conceive our universities as already, and likely to be more and more, great 
public institutions, deriving their income in increasing measure without 
any diminution of freedom from the State and the local authorities. 
It is to be hoped that the teachers of our universities will fari passu 
conceive themselves (as I believe they increasingly do) as lovers, seekers 
and preachers of pure knowledge for its own sake, vowed to no party when 
they speak from the chair, and rising above party so far as they can in 
all that they say or do in civic affairs outside. 






The visits of the British Association to Canada have hitherto very appro- 
priately coincided with definite stages in the progress of agricultural 
science and practice. It was at the Montreal Meeting of 1884 that Lawes 
and Gilbert presented their well-known paper on the sources of the fertility 
of Manitoba soils which ended the first great period of the development of 
agricultural science. This period had lasted eighty years ; it had been ushered 
in with the precise and scientific work of de Saussure published in 1804 ; 
its outstanding features had been the foundation of agricultural science 
by Boussingault in 1834, its enrichment by Liebig's brilliant essay of 1840, 
and its systematic development by Lawes and Gilbert at Rothamstcd 
from 1843 onwards. The whole purpose of the scientific workers of the 
period was to feed the plant ; in Gilbert's own words the message of the 
crops on the Rothamsted plots was, ' If you won't feed us we won't grow.' 
The success of the new science was remarkable ; its great triumph was the 
discovery of artificial fertilisers and their introduction into farming practice, 
and the workers had the great joy of seeing the crop yields rise considerably 
as the direct and recognised result of their labours. The problems were 
largely chemical, and agricultural science was regarded as simply a branch 
of chemistry. Gilbert's paper in 1884 was read before the Chemical 
Section, and it presented soil fertility as essentially chemical ; a fertile 
soil, he argued, is one containing much plant food, especially nitrogen ; it 
is one ' which has accumulated within it the residues of ages of natural 
vegetation, and it becomes infertile as this residue is exhausted.' At the 
time of the Toronto Meeting in 1897 a new period had begun, quietly 
and unnoticed, but growth was so rapid that at the Winnipeg Meeting in 
1909 the subject had grown right away from chemistrj'^ ; it had become a 
definite subsection, and its importance was so widely recognised that a 
recommendation was passed asking the Council to set it up as a full section, 
which was subsequently done. 

In this second period the purpose was not to feed the crop but to study 
it ; to discover what factors are concerned in the growth of crops and how 
they operate. This period, which may be called the period of free explora- 
tion, since the workers were not usually tied down to any particular tech- 
nical problem, began almost simultaneously in the United States, in France, 
and in Germany. As soon as agricultural science was studied in the 
United States it became evident that the cultivation of the soil was at 


least as important as the feeding of the crop. This fact had of course been 
fully recognised in the English experiments, but the English farmer was 
so skilled in cultivation that he could be taught but little by science. 
The early American work as developed by Kedzie at Michigan, King at 
Wisconsin, Hilgard, and Whitney, was largely physical, and it greatly 
widened the outlook of agricultural investigators, opening the way to the 
extensive physical and physico-chemical studies which have now become 
so characteristic a feature of American work. The French investigators, 
particularly Schloesing, Muntz, Berthelot, and Deherain, and the brilliant 
Eussian, Winogradsky, then in Paris, revealed a new world of soil micro- 
organisms, the wonder and mystery of which appealed to the imagination 
of the younger workers in a way that none of the older utilitarian work 
had done. The Germans methodically explored the fields thus opened 
up ; Hellriegel and Wollny accumulated a mass of data as to plant 
growth and soil changes which still remains of value to the student. These 
pioneers were succeeded by a host of followers whom it would be impossible 
to enumerate at length, and from whom it would be invidious to select a 
few. Moreover, the chemists and physicists of the old school were no longer 
left in sole possession ; van Bemmelen introduced the conception of colloids, 
and at a later date Mitscherlich, Baule, and others developed the idea of 
mathematical expressions for the data of agricultural science. Sachs and 
his pupils in Germany, Deherain, Maquenne and Demoussy in France, 
joined up the new science of plant physiology with agricultural science. 
The plant breeder also came in ; Gregor Mendel's work, after lying hidden 
for forty years, was revealed to the world by Bateson and was at once turned 
to agricultural use in England by one of Marshall Ward's pupils, R. H. 
Biffen ; and in the United States by Webber and others. The selection 
method was developed to a high pitch of perfection in Canada by William 
Saunders, a revered leader in our science, whose dignified presence and 
kindly words of greeting remain as a vivid recollection of our visit fifteen 
years ago. His mantle has fallen on his son Charles, who has continued 
and developed the work. 

The result of all this effort has been the accumulation of an enormous 
mass of information covering a very large part of the field with which 
agriculture has to deal. It has been essentially a pioneer period, with 
all the advantages of keen individual interest, controversy, sometimes 
even of excitement ; but also with the disadvantages of a certain lack of 
perspective, failure to follow up important issues and some narrowness of 
outlook inevitable when a single individual is working alone at a great 

Generalisations that have emerged. 

But in spite of these drawbacks several important generalisations have 
emerged. One of the most pregnant in possibilities for the future is the 
recognition that the plant is a very plastic organisation and can be modified 
to a considerable extent within certain limits. Two methods are adopted : 
breeding, which may be on observational lines or on the Mendelian method 
of picking out the desired unit characters from plants in which they occur 
and assembling them in a new plant ; and selection, in which a desirable 
plant is caused to produce seed from which stocks are multiplied. The 
scientific problems fall within the province of the science of genetics ; 
19S4 S 


the practical significance of the work lies in the fact that it greatly simplifies 
the agricultural problem by providing plants more or less suitable to the 
existing natural conditions where otherwise the expert would have the 
difficult, if not impossible, task of making the conditions suit the available 
plants. The work has proved extraordinarily fruitful and has given 
astonishing results even in our own time. It has played no small part in 
the amazing development of wheat growing in Canada. When the British 
Association went to Winnipeg in 1909 we were all impressed by the fact 
that Canada had then passed the 160-million bushel mark in production, 
but who would have thought that within fourteen years the production 
would exceed 474 million bushels ? Even in England, where wheat has 
been grown for 2,000 years, and where farmers have a long traditional 
knowledge of the crop, the new varieties introduced by Biffen have increased 
the yields and the certainty of yields. The triumphs of Webber and others 
in the United States, of Nielson Ehle with cereals in Sweden, Jeffreys 
in standardising the quality of cotton in Egypt, the Howards in producing 
wheats for India, to mention only a few, are still fresh in our minds. In 
the first period in the development of agricultural science the honours 
in the matter of practical applications lay with the chemists for the artificial 
manures, but in the present period we must admit that they lie with the 
plant breeders and selectors who, indeed, are only on the threshold of what 
they may yet accomplish. And this great practical purpose of finding 
or producing varieties of crops specially suited to local conditions would 
be further advanced if the work were done in co-operation with plant 
physiologists who could precisely define the modifications required. Much 
saving of time and effort could be effected if it were possible to set up some 
International garden where small quantities of the plant-breeders' produc- 
tions could be grown, including those which each one has rejected as being 
unsuitable to his particular requirements. Many of these unwanted out- 
casts might prove of value in other conditions. 

A second generalisation is that the soil is not a fixed, constant thing, 
but is pulsating with change. It contains a great population of micro- 
organisms which, among other activities, decompose the dead plant residues, 
producing nitrates, humic and other substances of great importance in crop 
production. But the numbers of these organisms fluctuate continually, 
and the bacteria at least change hourly ; the nitrates suffer equally ra^jid 
changes in amount. Even the mineral part of the soil is not constant in 
composition. Modern research work shows that many of the properties 
determining fertility in soils are due to the soil colloids, and some of the 
most important are attributable to calcium complexes.. These are unstable 
and are affected by the soil water. If the water is free from salts but 
contains carbon dioxide, the calcium may be replaced by hydrogen, and 
an acid soil results ; if the water contains sodium chloride, the calcium is 
replaceable by sodium and the resulting complex may readily give rise to 
an alkali soil. So far as is known, the changes are governed by the ordinary 
stoichiometric laws, the equilibrium following the usual course expected 
when a colloid is concerned. But the important fact emerges that any 
soil not well supplied with calcium contains within itself the possibility of 
becoming acid and therefore infertile, or alkaline and probably sterile, 
according to the nature of the soil water soaking through it. The various 
biological and chemical changes tend to alter the composition of the soil 



solution. Apparently, liowever, the colloids have a steadying or ' buffer- 
ing ' effect, reducing the degree of acidity caused by the production of acids 
and absorbing or precipitating various ions that might otherwise cause 

A third important generalisation that has emerged is that the relations 
of the plant and the soil are not rigidly fixed but are capable of consider- 
able variation, being profoundly influenced by a third factor, the climate. 
A soil moderately fertile in one set of conditions may be relatively unpro- 
ductive in another. This happens repeatedly with soils containing much 
clay or much coarse sand. In Table I. are given the mechanical analyses 
of two soils, one of which, the Lias clay from England, is quite unworkable 
and remains derelict under our conditions of cool temperature and moderate 
but frequent rainfall, by reason of its high content of clay and fine silt ; 
while the other, which contains even more clay, is capable of carrying good 
crops of grain and cotton under the hot dry conditions of the Sudan. 
The Western prairie soil is of similar physical type to that of the English 
Weald soil, but while the prairie soil under its climatic conditions of warm 
dry summer and cold dry winter is, and is likely to remain, a fertile wheat 
producer, the Weald soil under the wetter conditions of England is less 
fertile. In hot dry conditions the clay is no disadvantage and may even 
be an advantage, but in wet conditions it becomes a serious drawback ; 
indeed, it might be jjossible to find some mathematical relationship between 
rainfall and degree of objectionableness in clay. 


Soils of sijnilar type as regards mechanical analysis, 
greatly in fertility by reason of climatic differences. 



Eich in finer fractions 

Rich in coarser 

land very 
of culti- 



millet ct 



to culti- 








Lias clay 




2'2 in. 

35 in. 


Coarse sand, 2-0 to 
0-2 mm. 

Fine sand, 0-2 to 0-04 mm. 
Silt, 0-04 to 0-01 mm. . 
Finesilt,0-01 to0-002mm. 
Clay (below 0002 mm.) . 







1 12-6 











* Mainly black nodules of calcium carbonate. 

It appears then that if a fertile soil were carried from one country to 
another its productive power would not necessarily be carried with it. 
Its fertility is, to a considerable extent, dependent on the fact that it fits 
in with the climatic factors in producing conditions favourable to good 
growth of desirable crops. 

s a 


Complexity o£ the Problem : Methods of Attack. 

The agricultural investigator is thus confronted with three closely 
interlocking agencies — the plant, the climate, and the soil — each of which is 
variable within certain limits, and each plajang a large part in the crop 
production which it is his business to study. 

Confronted with a problem of this degree of complexity there are two 
methods of procedure : the empirical method of field observations and ex- 
periments, in which there is no pretence of great refinement and no expecta- 
tion that the same result will ever be obtained twice, it being sufficient 
if over an average of numerous trials a result is obtained more often than 
would be expected from the laws of chance ; and the scientific method, in 
which the factors are carefully analysed and their effects studied quantita- 
tively ; a synthesis is then attempted, and efforts are made to reconstruct 
the whole chain of processes and results. The scientific method is, of 
course, the one to which we are naturally attracted. But common 
truthfulness compels one to admit that up to the present the greatest 
advances in the actual production, of crops have been effected by the 
empirical method, and not infrequently by men who are really artists 
rather than men of science, in that they are guided by some intuitive pro- 
cess which they cannot explain, and that they have the vision of the result 
before they obtain it, which the scientific man commonly has not. 

The best hope for the future lies in the combination of the empirical 
and the scientific methods. This is steadily being accomplished by the 
recent strong infusion of science into the art of field experimentation, 
which has much enhanced the value of the field work and the trust- 
worthiness of its results. Modern methods of replication, such as have been 
worked out at Rothamsted, and in the United States by Harris of the 
Carnegie Trust (Cold Spring Harbor), Kiesselbach in Nebraska, Myers 
and Love of Cornell, and others, constitute a marked improvement in plot 
technique. And the figures themselves, besides being more accurate, can 
be made to yield more information than was formerly the case. 

Great advances have been made in the methods of analysing the results. 
The figures are never the same in any two seasons, since the chmatic con- 
ditions profoundly affect the yields. A few men, Uke J. H. Gilbert, have the 
faculty of extracting a great deal of information from a vast table of figures, 
but in the main even the trained scientific worker can make very little 
of them. The reason is that he has been brought up to deal with cases 
where only one factor is varying, while the growth of plants involves the 
interaction of three variable factors : the plant, the soil, and the climate. 
It is impossible to apply in the field the ordinary methods of the scientific 
investigator where single factors alone are studied ; very different 
methods are needed, adapted to the case where several factors vary simul- 

Fortunately for agricultural science, statisticians have in recent years 
worked out methods of this kind, and these are being modified and developed 
by R. A. Fisher and Miss Mackenzie for application to the Rothamsted 
field data. It so happens that this material is very suitable for the purpose, 
since a large number of the field experiments have been repeated every 
year for seventy or eighty years on the same crop and on the same piece 
of land, using the same methods ; the field workers also remain the same 
for many years, the changes being rare and without break in continuity. 


Although the statistical investigation is only recently begun, mathematical 
expression has already been given to the relationship between rainfall 
and yield of wheat and barley under different fertiliser treatments, and 
precision has been given to some of the ideas that have hitherto been only 
general impressions. If on an average of years a farmer is liable to a 
certain distribution of rainfall, it is becoming possible to advise as to 
fertiliser treatment which enables the plant to make the best of this rainfall. 

Unfortunately, few other Experimental Stations possess such complete 
masses of data as Rothamsted. Methods are now being devised, however, 
both by Fisher and by the able English investigator who modestly conceals 
his identity under the pseudonym ' Student,' for the study of smaller 
numbers of data, and it is hoped that these or others equally effective 
will be applied to the results of field experiments accumulated at various 
Experimental Stations throughout the world. A massed attack by a 
competent band of statisticians on the whole of the data of the best Experi- 
mental Stations, dealing with yields of crops under different conditions of 
nutrient supply, temperature, rainfall and other factors that go to make up 
the aggregate called season, would yield information of extraordinary value. 

Investigations of this kind, however, are necessarily slow, and they do 
not themselves afford complete information ; their value lies in the fact 
that they reduce a very complex problem to a set of single-factor problems 
of the type with which the scientific investigator is already familiar. 
In the meantime, while this work is proceeding, much is being done 
by observational methods. At Rothamsted the field plots are under 
continual observation by a group of three workers, a physiologist, an 
ecologist, and an agriculturist, who study such factors as rate or habit 
of growth, earliness of starting or maturing, degree of resistance to 
insect or fungus attack ; their observations are fully recorded and brought 
before the chemical, physical and botanical departments at regular and 
frequent intervals. Certain of the experiments are repeated at other 
centres on closely similar lines for purposes of comparison. In consequence 
our old field plots which have been studied for the past eighty years by 
Lawes, Gilbert, Warington, and Hall, and might have been supposed to 
have no further tales to tell, are found to be still yielding results of great 
interest in agricultural science and practice. 

The Results Obtained : Alterations in the Plant. 

We shall begin with the results obtained by effecting alterations in the 
jjlant. Reference has already been made to the changes brought about 
by the plant breeder, and we need not stop to argue whether the great 
improvements in crops made in pre-Mendelian days by the Suttons and 
Findlay in potatoes, by Chevalier in barley, by the Gartons in oats, Vilmorin 
in sugar beet, and others, should be labelled empirical or scientific. There 
are certain other changes in plants, however, of a purely temporary nature, 
which have been induced by changes in conditions. It is a commonplace 
among farmers that certain soil conditions influence not only the yield 
but also the quality of crops. The leaf and root are more easily affected 
than the seed. Thecase of mangolds has been investigated atRothamsted ; 
the sugar content of the root, an important factor in determining feeding 
value, was increased by increasing the supply of potassium to the crop. 
Middleton at Cockle Park showed that grass increased in feeding value—- 


quite apart from any increase in quantity — when treated with phosphates. 
Potatoes are considerably influenced by manuring ; increasing the supply 
of potassium influences the composition of the tubers and also that much 
more impalpable quality — the cook's estimate of the value of the potato ; 
while we have found at Rothamsted that a high-class cook discriminated 
between potatoes fertilised with sulphate of potash and those fertilised with 
muriate of potash, giving preference to the former. 

Grain is more difficult to alter by changes in environmental condi- 
tions ; indeed, it appears that the plant tends to produce seed of substan- 
tially the same composition whatever its treatment — with the important 
exception of variation in moisture supply. Mr. Shutt has explored the 
possibilities of altering the character of the wheat grain by varying the soil 
conditions, and finds that increases in soil moisture decrease the nitrogen 
in the grain. Similar results have been obtained in the United States. 

On the other hand, in England the reverse seems to hold, at any rate 
for barley. This crop is being fully investigated at the present time under 
the Research Scheme of the Institute of Brewing, because of its importance 
in the preparation of what is still Britain's national beverage. Increased 
moisture supply increases the percentage of nitrogen in the grain, and so 
also does increased nitrogen supply, though to a much less extent ; on 
the other hand, both potassic and phosphatic fertilisers may decrease the 
percentage of nitrogen, though they do not always do so ; the laws regu- 
lating their action are unknown to us. 

The practical importance of these problems of regulating the composi- 
tion of the plant lies in the fact that the farmer can control his fertiliser 
supply, and also to some extent his moisture supply, so that it lies within 
his power to effect some change should he wish to do so. 

The following are the nitrogen contents and the valuations of barley 
grown in the same season from the same lot of seed on farms only a few 
miles apart : — 

Effect of Moisture. 

Drier soil Moist land 

Nitrogen per cent, in grain .. ..1-44 1"80 

Valuation per quarter of 448 lb. . . 52s. M. 41s. Qd. 

Effect of Nutrients. 

No nitrogenous Nitrogenous 
manure manure 

Nitrogen per cent, in grain . . . . r379 1"464 

Valuation per quarter of 448 lb. . . 53s. 52s. 

At present we know but little about the matter and we are not in a 
position to advise the farmer as to how he may use these facts to the full 
advantage. The complete study of the problem necessitates the co-opera- 
tion of a plant physiologist. 

There is another direction also in which alterations in the plant would 
be of great value if only we knew with certainty how to bring them about. 

In agricultural science one sometimes thinks only of the crop and the 
factors that affect its growth. But in agricultural practice there is often 
another partner in the concern : a pest or parasite causing disease. The 
amount of damage done by pests and diseases to agricultural crops is 


astounding; in Britain it is probably at least 10 percent, of the total 
value of the crops and the loss is probably some 12,000,000/!. sterling per 
annum ; in some countries it is considerably more. Indeed, the number 
of insect pests and of harmful fungi and bacteria that skilled entomologists 
and mycologists have found in our fields might almost lead us to despair 
of ever raising a single crop, but fortunately the young plant, like the 
human child, grows up in spite of the vast number of possible deaths. 
The saving fact seems to be that the pest does harm only when three sets 
of conditions happen to occur together : the pest must be present in the 
attacking state ; the plant must be in a sufficiently receptive state ; and 
the conditions must be favourable to the development of the pest. It is 
because this favourable conjunction of conditions comes but rarely that 
crops manage to survive. And this gives us the key to control if only 
we knew how to use it. Complete control of any of these three conditions 
would end all plant diseases. Unfortunately, control is never complete 
even in glasshouse culture, still less out of doors. But even partial control 
would be very helpful. All these pests go through life cycles, which are 
being studied in great detail all over the world, and especially in the United 
States. Somewhere there occurs a stage which is weaker or more easily 
controlled than others, and the pest would become harmless if the chain 
could be broken here or if the cycle could be sufficiently retarded to give 
the plant a chance of passing the susceptible stage before it is attacked. 

The plants themselves, as we have just seen, are in some degree under 
control, and if they could be pushed through the susceptible stages before 
the pest was ready they would escape attack. Barley in England is some- 
times considerably injured by the gout fly [Chlorops tceniopus). The larvae 
emerge in spring from the eggs laid on the leaves and invariably crawl 
downwards, entering the young ear if, as usually happens, it still remains 
ensheathed in leaves. J. G. H. Frew, at Rothamsted, has shown that early 
sowing and suitable manuring cause the ear to grow quickly above the 
track of the larvas, and thus to escape injury. E. A. Andrews, in India, has 
found that tea bushes well supplied with potassic fertiliser escape attack 
from the mosquito bug (Helopeltis) for the rest of the season, apparently 
because bushes so treated become unsuitable as food to the pest. And 
further, the conditions are alterable. H. H. King, in the Sudan, has effected 
some degree of control of the cotton thrips {Heliothips milieus) by giving 
the plant protection against the drying North w^ind and so maintaining 
a rather more humid atmosphere— a condition in which the plant flourishes 
niore than the pest. Tomatoes in England suffered greatly from Verticillium 
wilt till it was found that a small alteration of temperature threw the attack 
out of joint. They are also much affected by stripe disease {B. lathyri), 
but they become more resistant when the supply of potash is increased 
relative to the nitrogen. It has recently been maintained, though the proof 
is not yet sufficient, that an altered method of cultivating wheat in England 
will afford a good protection against bunt. These cultural methods of 
dealing with plant diseases and pests offer great possibilities, and a close 
study jointly by plant physiologists and pathologists of the responses of 
the plant to its surroundings, and the relationships between the physio- 
logical conditions of the plant and the attacks of its various parasites, 
would undoubtedly yield results of great value for the control of plant 
diseases. Again, however, the plant bre-'^der can save a world of trouble 


by producing a variety resistant to the disease ; or there may fortunately 
be found an immune plant from which stocks can be had, as in the case 
of the potatoes found by Mr. Gough to be immune from the terrible 
wart disease. 

Control of Enviroiunental Factors. 
It thus appears that, if only plant breeders and plant physiologists 
could learn to alter existing plants or to build up new plants in such a way 
that they should be well adapted to existing soil and climate conditions, 
and not adapted to receive disease organisms at the time the organisms 
are ready to come— if only they could do this all agricultural land 
would become fertile and plant diseases and pests would become 
ineffective : at any rate until the pests adapted themselves to the new 
plants. Although no one can set limits to the possibilities of plant breeding 
and plant physiology, we cannot assume that we are anywhere near this 
desirable achievement or that we are likely to be in our time. There will 
always remain the necessity for altering the environmental conditions to 
bring them closer to the optimum conditions for the growth of the plant. 
No attempt is yet made in the field to control two of the most important 
of the factors : the light and the temperature, though it is being tried 
experimentally. There is a great field for future workers here ; at present 
plants iitilise only a fraction of the radiant energy they receive. At 
Rothamsted attempts have been made by F. Gr. Gregory to measure this 
fraction ; the difficulties are considerable, but the evidence shows that our 
most efficient plants lag far behind our worst motor-cars when regarded 
as energy transformers for human purposes. One hundred years ago the 
efficiency of an engine as transformer of energy was about 2 per cent. ; 
now, as a result of scientific developments, it is more than 30 per cent. 
To-day the efficiency of the best field crops in England as transformers of 
the sun's energy is about 1 per cent.^ : can we hope for a similar develop- 
ment in the next hundred years ? If such an increase could be obtained 
an ordinary crop of wheat would be about 400 bushels per acre, and farmers 
would feel sorry for themselves if they obtained only 200 bushels. But we 
are only at the beginning of the subject. Increases in plant growth amount- 
ing to some 20 or 25 per cent, have been obtained by V. H. Blackman in 
England under the influence of the high-tension electric discharge, which 
presumably acts by increasing in some way the efficiency of the plant as an 
energy transformer. Possibly other ways could be found. It needs only a 
small change in efiiciency to produce a large increase in yield. Much could 
be learned from a study of the mass of data which could be accumulated 
if agricultural investigators would express their results in energy units as 
well as in crop yields as at present. 

Interesting results may be expected from the attempts now being made 
in glasshouse culture both in Germany and at Cheshunt to increase the 
rate of plant growth by increasing the concentration of the carbon dioxide 
in the atmosphere. 

Control of the Soil Factors. 
The soil factors lend themselves more readily to control and much has 
been already achieved. Water supply was one of the first to be dealt 

1 The remaining energy being largely used up in transpiration. This figure refers 
to the total radiation received by the leaf, and not to the fraction received by the 
cbloroplast surface. For this latter the value is much higher. 

jr.— AGRICULTURE, 265 

with. Civilisatiou arose in the dry regions of the earth, and as far back as 
5,000 years ago irrigation was so advanced as a practical method that 
it came into the ordinances drawn up by the great Babylonian king 
Hammurabi. The chief problems at the present time are to discover 
effective means of economising water and to ascertain, and if possible con- 
trol, tlie relationships between the soil, the water, and the dissolved sub- 
stances in the water. Economical use of water is necessary because it 
allows larger areas to be irrigated, and because water beyond a certain 
amoiint injures the soil and asphyxiates the plant roots. This part of the 
problem is largely one of engineering and police control. The more serious 
problem, perhaps the most serioiis confronting agricultural science to-day, 
is that presented by the soluble matter in the water and the soil. The 
terrible spectre of alkali looms aliead of every irrigation project ; it may 
be kept under control for a longer or shorter time or it may completely 
wreck the scheme. Instances could be multiplied of schemes started with 
great expectations of results yet yielding only disappointment and loss. 
A volume could be filled with the tragedies of the alkali problem. Neutral 
salts, particularly sodium sulphate, are not harmful to plants unless their 
concentration exceeds a certain critical value ; indeed, some of the heavy 
soils in dry countries, as in Egypt and the Sudan, become unworkable if 
washed with pure water ; they remain flocculated only because some soluble 
salts are present. Chlorides beyond a critical concentration are more 
harmful to the plant, but sodium carbonate is deadly, and there is no 
certain way at present of overcoming its effects. 

The empirical method has apparently gone as far as it can, and nothing 
more can be expected until some fresh opening is discovered by scientific 

Almost equally important is the more efficient utilisation of water in 
districts where the rainfall is sufficiently high to obviate the need for 
irrigation, but insufficient to allow of any wastage of water. The practical 
work of the Utah agriculturists as exemplified by Widstoe, and the labora- 
tory results of Keen at Rothamsted, all indicate that something can be 
done. It is legitimate to hope that the next great advance will come from 
Canada, where in the West there are admirable opportunities for studying 
the problem. 

Inseparably bound up with water supply are the questions of cultiva- 
tion and of drainage, which affect not only the water but the air supply 
to the roots. This former subject is now attracting considerable attention : 
the great need is to discover means for expressing cultivation in exact 
physical and engineering units. The measurements of Keen and Haines 
at Rothamsted, and the chemical work of A. F. Joseph, N. Comber, and 
others on clay, and of Oden, Page, and others on humus, indicate the 
possibility of finding exact expressions and of effecting co-operation with 
the workers in the new fields of agricultural engineering. 

Another soil factor which readily lends itself to some degree of control 
is the amount of plant nutrients present. The possibility of increasing this 
by means of manure has been so frequently explored in field trials that it 
has sometimes been regarded as almost a completed story ; indeed, 
Rothamsted tradition affirms that Lawes himself once gave orders to have 
the Broadbalk field experiments discontinued because they had nothing 
further to tell ; it was only the earnest persuasion of Gilbert that caused 


liiiu to countermand the order. So far from the subject being exhausted, 
it still bristles with problems. The new nitrogenous fertilisers, resulting 
from war-time activities in nitrogen fixation ; the need for reducing the 
cost of superphosphate ; the change in character of basic slag ; and the 
Alsatian development in potash production are producing changes in the 
fertiliser industry the full effects of which are not easy to foresee. Economic 
pressure is driving the farmer to derive the maximum benefit from his 
expenditure on fertilisers, lime, farmyard manure and other ameliorating 
agents, and is compelling a more careful study of possibilities hitherto 
disregarded, such as the use of magnesium salts, silicates, and sulphur as 
fertilisers, and, above all, a much more precise diagnosis of soil deficiencies 
than was thought necessary in pre-war days. 

But there are more fundamental problems awaiting solution. It 
is by no means certain that we know even yet all the plant nutrients. 
The list compiled by Sachs many years ago includes all needed in relatively 
large amounts, but Gabriel Bertrand has shown that it is not complete 
and that certain substances — he studied especially manganese — are essen- 
tial, although only in very small amounts. Miss Katherine Warington, 
working with Dr. Brenchley at Rothamsted, has shown that leguminous 
plants fail to develop in the so-called complete culture solution unless a 
trace of boric acid is added. Maze has indicated other elements needed in 
small amounts. 

Another problem needing elucidation is the relationship between the 
quantity of nutrients supplied and the amount of dry matter produced. 
Is dry matter production simply proportional to nutrient supply, as Liebig 
argued, with the tailing oS beyond a certain point, as demonstrated by 
Lawes and Gilbert, or is it always less than this, as indicated by 
Mitscherlich's logarithmic curve, or is the relationship expressed by 
one of the more complex sigmoid curves as there is some reason to 
suppose ? We do not know ; and the problem is by no means simple, 
yet it governs the ' diminishing returns ' about which farmers now hear 
so much. Again, very little is known of the relationship between 
nutrition and period of growth. One and the same quantity of a 
nitrogenous fertiliser, for example, may have very different effects 
on the plant according as it is given early or late in life ; not only is there 
a difference in quantity of growth, but also in the character of the growth. 
Late dressings cause the characteristic dark-green colour to appear late 
in the season, and thus affect the liabilit}' to fungoid diseases ; they increase 
the percentage of nitrogen in the grain and they may give larger increases 
of crop than early dressings. 

Investigations are needed to find the best methods of increasing the 
supply of organic matter in the soil and its value for the different crops 
in the rotation. 

All these problems will sooner or later find some solution. But there 
remains a greater problem of more importance than any of them : the 
linking-up of plant nutrition studies with those of the soil solution. As 
our cousins in the United States were the first to emphasise, the fundamental 
agent in the nutrition of the plant is the soil solution, and they have 
made a remarkable series of investigations into what appeared at one time 
a hopeless proposition — the physico-chemical interactions between the 
soil and the soil water. Whitney and Cameron began the work, and it 
has gone on with much controversy — as important scientific investigations 


always do — and it is now being attacked with much vigour by some of 
the younger scientific workers, particularly in the Californian school : 
Burd, Hoagland, Kelley, Lipman, Stewart, Sharp, and others. There is 
also some valuable work by Gola and other Italians. The natural soil 
solution is not always the best for the growth of plants. It is reasonable 
to suppose that the most efficient method of using fertilisers would be for 
making up the soil solution to the optimum composition and concentration 
for each stage of the growth of the crop. Unfortunately, this cannot yet 
be done. The added fertiliser does not simply increase the concentration 
of the soil solution to the precise extent that might be expected ; there 
are interactions, absorptions, and base exchanges of the kind studied 
first by Way, much later by van Bemnielen and by Gcdroiz, and more 
recently by Hissink and by Wiegner. Further, the plant relationships are 
not constant ; there is apparently — though this is not certain — more 
response to certain nutrients at one time of its life than at another. A great 
advance in crop production may be expected when the soil chemists have 
discovered the laws governing the soil solution, when the plant physiologists 
can give definite expression to the plant's response to nutrients, and when 
someone is able to put these results together and show how to alter the soil 
solution so that it may produce the maximum effect on the plant at the 
particular time. The new soil chemistry will yet have its triumphs. 

The Soil Micro-organisms : Can they be Controlled ? 

It is now more than forty years since the discover}' of the great impor- 
tance of micro-organisms in determining soil fertility. Practical applications 
necessarily lag far behind ; but already three have been made, each of 
which opens out great possibilities for the future. The long-standing 
problem of inoculation of leguminous crops* with their appropriate organ- 
isms has already been solved in one or two of its simple cases, chiefly lucerne 
on new land, and the new process has helped in the remarkable extension 
of the lucerne crop in the United States and in Denmark. We believe at 
Rothamsted that the mqp-e difficult English problem is now solved also. 
Interesting possibilities are opened up by the observation that a prelimi- 
nary crop of Bokhara clover seems to facilitate the growth of the lucerne. 

The organisms effecting decomposition are now coming under control, 
and are being made to convert straw into farmyard manure (or a material 
very much like it) without the use of a single farm animal. The process 
was worked out at Rothamsted, and is being developed by the Adco 
Syndicate, who are now operating it on a large scale and are already 
successfidly converting some thousands of tons of straw annually into 
good manure. 

The third direction in which control of the soil organisms is being 
attempted is by partial sterilisation. This process is much used in the 
glasshouse industry in England, and it has led to considerable increases 
in crop yields. The older method was to use heat as the partial sterilising 
agent, and this still remains the most effective,, but owing to its costliness 
efforts have been made to replace it by chemicals. Considerable success 
has been attained ; we have now found a number of substances which seem 
promising. Some of these are by-products of coal industries ; others, 
such as chlor- and nitro-derivatives of benzene or cresol, are producible as 
crude intermediates in the dye industry. 


The Need for Fuller Co-operation. 

Looking back over the list of problems it will be seen that they are all 
too complex to be completely solved by any single worker. Problems of 
crop production need the co-operation of agriculturists, plant physiologists, 
soil investigators, and statisticians. Even plant breeding necessitates the 
help of a physiologist who can specify just what the breeder should aim 
at producing. And this gives the key-note to the period of agricultural 
science on which we have now entered — it is becoming more and more a 
period of co-operation between men viewing the problem from different 
points of view. Good individual work will of course always continue to 
be done, but the future will undoubtedly see a great expansion of team work 
such as has already led to important results in medical research, and 
such as we know from our experience at Rothamsted is capable of giving 
admirable results in agricultural science. 

The team work should not be confined to individuals working at the 
same institution. The world would gain greatly if co-operation such as 
now exists between the Imperial College Botany School and Rothamsted 
could be effected between other great institutions devoted to agricultural 
science in the various countries of the world. To take only one illustration : 
how much could be accomplished in the study of the very difficult alkali 
problem if it were possible to organise a team representing such great agri- 
cultural stations as, for instance, California and Utah, the Departments of 
Agriculture of India and other of the great Dominions affected, Rothamsted, 
Hissink's school, with power to lay down experiments anywhere and money 
to carry them out. And if extended co-operation of this kind should prove 
impossible of attainment, much could be done by fostering co-operation 
between the Agricultural Institutions of the Empire. There are certain 
great problems which are common to large parts of the Empire where the 
experience of one part would b'e of great value to the rest. The institutions 
in Britain, for example, have experience of problems connected with land 
long since settled and brought into cultivation, where men must produce 40 
or more bushels per acre of wheat and 6 to 10 tons per acre of potatoes to 
make these crops pay, and where animal husbandry must be run on sound 
and economic lines. Canada has an unrivalled exj)erience with wheat, and 
in the Western provinces has a magnificent chance for studying one of the 
most important problems of the day-^the water supply to the crop. 
Australia, New Zealand, South Africa, East, West, and Tropical Africa, 
India, the West Indies — to mention only a few in the great family that 
forms the British Empire — all have their special lines in agricultural 
development ; each has some achievement that can be shown with pride 
and in the certainty that its study will benefit others. The Empire has 
already its Conference of Premiers, why should it not have its conference for 
agricultural science and practice ? 

With fuller co-operation both of men and of institutions we could 
do much to overcome the present difficulty in regard to utilising the in- 
formation we already possess. In the last thirty years an immense stock 
of knowledge has been obtained as to soils and crops — knowledge that 
ought to be of supreme value in interpreting the facts of Nature as shown 
in the field. It is stored in great numbers of volumes which line the shelves 
of our libraries, and there much of it rests undisturbed in dignified oblivion. 
In the main it consists of single threads followed out more or less carefully ; 


only rarely does some more gifted worker show something of the great 
pattern which the threads compose. But even the most gifted can see but 
little of the design ; the best hope of seeing more is to induce people to work 
in groups of two or three, each trained in a different school and therefore 
looking at the problem from a different point ; each seeing something 
hidden from the rest. Unlike art, science lends itself to this kind of team 
work ; art is purely an individual interpretation of Nature, while science 
aims at a faithful description of Nature, all humanistic interpretation being 
eliminated. There is certainly sufficient good-will among the leaders of 
agricultural science to justify the hope of co-operation ; there are probably 
in existence foundations which would furnish the financial aid. 

And that leads to my last point. What is the purpose of it all ? Team 
work, co-operation, the great expenditure of time and money now being 
incurred in agricultural science and experiment — these are justified only 
if the end is worthy of the effort. The nineteenth century took the 
view that agricultural science was justified only in so far as it was useful. 
That view we now believe to be too narrow. The practical purpose is of 
course essential; the station must help the farmer in his daily difficulties — • 
which again necessitates co-operation, this time between the practical 
grower and the scientific worker. But history has shown that institutions 
and investigators that tie themselves down to purely practical problems do 
not get very far ; all experience proves that the safest way of making 
advances, even for purely practical purposes, is to leave the investigator 
unfettered. Our declared aim at Rothamsted is ' to discover the principles 
underlying the great facts of agriculture and to put the knowledge thus 
gained into a form in which it can be used by teachers, experts, and farmers 
for the upraising of country life and the improvement of the standard of 

This wider purpose gives the investigator full latitude, and it justifies 
an investigation whether the results will be immediately useful or not — so 
long as they are trustworthy. For the upraising of country life necessitates 
a higher standard of education for the countryman ; and education based 
on the wonderful book of Nature which lies open for all to read if they but 
could. How many farmers know anything about the remarkable structure 
of the soil they till, of its fascinating history, of the teeming population 
of living organisms that dwell in its dark recesses ; of the wonderful wheel 
of life in which the plant takes up simple substances and in some mysterious 
way fashions them into foods for men and animals and j)acks them with 
energy drawn out of the sunlight — energy which enables us to move and 
work, to drive engines, motor-cars, and all the other complex agencies of 
modern civilisation ? No one knows much of these things ; but if we knew 
more, and could tell it as it deserves to be told, we should have a storv 
that would make the wildest romance of hvmian imagination seem dull 
by comparison and would dispel for ever the illusion that the country 
is a dull place to live in. Agricultural science must be judged not only 
by its material achievements, but also by its success in revealing to the 
countryman something of the wonder and the mystery of the great open 
spaces in which he dwells. 



Seismolo^ical Investigations* — Twenty-ninth Report of Committee 
(Professor H. H. Turner, Chairman ; Mr. J. J. Shaw, Secretary ; 
Mr. C. Vernon Boys, Dr. J. E. Crombie, Dr. C. Davison, Sir F. W. 
Dyson, Sir R. T. Glazebrook, Dr. Harold Jeffreys, Professor 
H. Lamb, Sir J. Larmor, Dr. A. Crichton Mitchell, Professors 
A. E. H. Love, H. M. MacDonald, and H. C. Plummer, Mr. W. E. 
Plummer, Professor R. A. Sampson, Sir A. Schuster, Sir Napier 
Shaw, and Dr. G. T. Walker). [Drawn up by the Chairman except 
where otherwise mentioned.^ 


There is no modification to report in the general situation at Oxford. The tenant 
of the house purchased by Dr. Crombie's benefaction shows no disposition to move ; 
but the work has been carried on in the ' Students' Observatory ' without serious 

The salary for Mr. J. S. Hughes, provided for the first year entirely by the generosity 
of Dr. Crombie, has for the second year been provided half by Dr. Crombie and half 
by the Board of Scientific and Industrial Research. Mr. Hughes has taken over the 
work of determining epicentres and times, under the general supervision of Professor 
Turner, and by this welcome addition to our resources arrears are being steadily 
reduced, as mentioned below. 


Seismologj' has sustained further severe losses by the deaths of Dr. Otto Klotz of 
Ottawa and Professor Omori of Tokyo. Our deep sympathies are extended to Japan, 
not only for this personal loss, but on account of the terrible calamity which befell 
Tokj^o and Yokohama in the devastating earthquake of September 1. 

There is to be a meeting of the International Union for Geodesy and Geophysics 
in Madrid in October next. Professor H. H. Turner and Mr. J. J. Shaw have been 
in nominated by our National Committee as delegates for Seismology. 


Nothing has yet been heard of the seismograph taken to Christmas Island by the 
Eclipse observers in 1922. Writing under date June 4, Mr. H. S. Jones, now H.M. 
Astronomer at the Cape, promises to write again to Christmas Island on the 

Mr. J. J. Shaw has despatched two of his seismographs to Entebbe in Uganda, and 
one to Fordham University, New York. These were indeijendently purchased, but 
are mentioned to show the expanding distribution of machines of the type approved by 
the Committee. 

Another instrument has been prepared by him for exhibition at Wembley, whither 
some maps showing the distribution of epicentres and of observing stations, and a 
set of the publications, are also being sent. 

The performance of the Milne-Shaw seismograph has, moreover, been tested by 
Professor Rothe on the experimental talile at Strasbourg with very satisfactory results. 
The curve representing the motion of the table is almost identical with that shown by 
the seismograph. 



[The remainder of this section is due to Mr, Shaw.] 

The movements of the table are produced by an electrica lly driven cam, the amplitude 
and periodicity of which can be changed at will. Its motion is recorded mechanically 
on smoked paper. The seismograph is placed upon the table, but records photo- 
graphically. Both curves are timed by the same electric circuit. The apparatus was 
tested with both simple and complex periods and in each case faithful records were 

Fig. 1 illustrates curves where the periods of the table and pendulum were alike 
(a condition when distortion due to synchronism is likely to develop). Curve A 
shows a tabic movement of 0"13 mm. magnified 109 times. B is the corresponding 
seiamogram, in which, by the Galitzin formulas, the magnification should be 187. 

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1 ■ I ■ ' ■ . I , 1 ' ' ' I I ' 

» ' 1 I ::••'.'■ i i ;■■ i ! 

:i i' ■: :! ! \\ li 

1 -I .1 

1 ■ I • . 

! i; -1 .| 

:: i; li i: : i; ;: 

■■■' Mniijiii 

1 ! ' j . I M '. 

! ; I 

I . I I . : I i I ■ 

: M :: ii li ii i: i! li i ;< i i! 

i! I i' \\ : 

:i ;1 ;| i; I : ! ; 1 1 ' I ;; ! 1 1 
■ I;:i'i!:;i!i' : 

I! ; :! ' !: 

H I I 

I !{< I! il II I! 

I ;i 

ii Mill!! 

Ii !! 11 II !1 il II !' ' 

!l i 'I If t II \\ 

I I 


II 1 

ii Id ^ .^ $ 1 

In sc r i lotion TTlttflC - j/» ft Vv 

Strasbourg i':;24 march Z"^ 

Fig. 1. 

Measurement of the curve shows magnifications ranging between 181 and 187, illus- 
trating not only the fidelity of the seismogram but also the close agreement between 
present practice and the formula in use. 

While referring to instrumental points of this kind, it is interesting to observe how 
two machines standardised to similar constants and fully damped do produce similar 



records. The two seismograms reproduced side by side in fig. 2 are of the same 
earthquake taken upon different machines operating in the same azimuth and on the 
same time circuit, but in separate buildings 60 feet apart. The machines were on test 
at West Bromwich, their standardising being incomplete. The respective nominal 
magnifications were 141 and 161, which accounts for the slight difference in amplitude. 
The amplitudes of the large wave after the 26th minute are in the ratio of 141 to 163. 


Bulletins and Tables. 

The ' International Seismological Summaries ' for July to September 1918 and 
October to December 1918, for January to March 1919, April to June 1919, and July 
to September 1919, have been printed and distributed. October to December 1919 
is in the press ; and for the year 1920, January to March is being finally checked for 
press, and the first draft is made for the months April to August. This steady pro- 
gress has been rendered possible by the services of Mr. J. S. Hughes. 


Depth of Focus. 

A list of cases of abnormal focus up to May 1918 was given in the last report. 
To these may now be added 

Geoup I. (High Focus). [PJ 










July 8 




26-5 N 

91-2 E 


+ (> 


Sept. 7 





Sept. 8 


46-5 N 

151-4 E 


+ 20 


Sept. 11 





April 30 




19-5 S 

1730 W 


+ 7 


May 6 




6-0 S 

1.530 E 


+ 36 


May 29 




31-5 N 

100-5 E 




Oct. 12 




2-0 S 

102-5 E 


+ i2 

(Group II. represents the vast majority of earthquakes at normal depth.) 

Group III. (Deep Focus). [P] 

d. h. m. s. ° ° Depth s. 

1918 Nov. 18 18 41 45 1 „ 197 .-.^ -u nin 9^ 

1918 Nov. 23 22 57 45] ^^^ ^^^''^ +"0^0 "^5 

1918 Dec. 14 18 39 15 130 S 1G6-8 E +-0.30 —25 

1918 Dec. 25 10 21 10 7-0 S 153-0 E +-070 ? 

1919 Jan. 13 20-5 S 178-5 W +030 -30 
1919 Mar. 1 13 36 9-0 N 141-0 E +030 -18 
1919 Mar. 2 3 26 40 | 

1919 Mar. 2 11 45 10 43-7 S 77-0 W +020 -9 

1919 Mar. 9 3 16 45 I 

1919 Mar. 13 14 16 55 8-5 S 124-5 E (suggested) -65 

1919 Mar. 16 7 33 101 9 . j. ,270 E +015 ' ' 
1919 Mar. 16 15 3 / " ^ JN i^7 U Ji + U15 

1919 Apriin 20 53 5 14-5 N 91-0 W +010 ? 

1919 May 3 51 55 40-7 N 145-8 E +-005 -7 

1919 June 1 6 51 13 25-7 N 124-8 E +040 -15 

1919 Aug. 18 16 55 251 i7f.« 177 sw 1 c\^n tA 

1919 Au|. 18 20 52 o} ^^'^ ^ ^^^'^ ^^ +<^^^ -^* 

1919 Aug. 31 17 20 34 15-7 S 167-3 E +015 -13 

1919 Oct. 27 3 40 48 16-0 S 69-5 AV +-040 ^t4 

1919 Nov. 6 7 13 10 13-5 N 59-0 W +-010 ? 

1919 Nov. 20 14 11 38 130 S 166-8 E +040 -29 

In some of these cases the rule of insisting on the existence of evidence from both 
epicentral and anticentral stations has been relaxed ; for with accumulating evidence 
of variation in depth, it is natural to accept plain indications without too exacting 
conditions. But generally the double evidence is available. 

With regard to the position tentatively occupied in the last report, that there are 
three definite surfaces at which shocks occur, it will be seen that there are seven 
entries out of fifteen with depth either + -030 or + -040 ; there are two greater 
( + •050 and +-070), six less ( + -020, +-015, +-015, +-010, +-010, and +-005), and 
one uncertain : all these belotv the normal, with a mean value near +-030. On the 
side above the normal the mean value — -025 is not far from any of the entries. The 
difference -055 between these extremes is comparable with Galitzin's -060 between 
his uppermost and lowest surfaces, so that the hypothesis of identity maj' reasonably 
be retained for trial, though the three critical depths are clearly regions of maximum 
occurrence rather than definite surfaces. 


Further study of the 21 -minute periodicity led, by a devious route, to the con- 
clusion that it is controlled by the Moon, and is of the nature of a tidal effect. The 
re-examination of the material (especially the series of 6,000 Jamaica earthquakes) 
from this point of view is not yet complete, and has involved more than one change 
of hypothesis in detail. The general idea that the meridian passage of the Moon on 
•ach day should b« taken as the reference point, and that there are ati exact number 

1924 T 


of periods in each lunar day, has, from the first, given results strongly supporting the 
idea of lunar action. But the exact number of periods was at first wrongly assessed 
as 71, then as 70, and ultimately appears to be 68. In view of these successive 
changes, it is clearly desirable to obtain complete confirmation before publishing the 
details. It will easily be seen that each modification of the hypothesis in dealing 
with such a large mass of material has involved a good deal of work. 

Local Variations of the Earth's Gravitational Field.— Rejwrt 
of Committee (Col. H. G. Lyons, Chairman ; Capt. H. Shaw, Secretary ; 
Professor C. Veenon Boys, Dr. C. Chree, Col. Sir G. P. Lenox- 
CoNYNGHAM, Dr. J. W. EvANS, Mr. E. Lancaster Jones ; the 
Director-General, Ordnance Survey ; tte Director, Geological 
Survey of Great Britain). 

During the year investigations have been conducted with the Eotvos Torsion Balance, 
both in the laboratory and in the field. A new model of this instrument manufactured 
by a British firm has been tested, and compared with the instrument belonging to the 
Science Museum. These tests confirmed the superiority of the double beam instrument 
over the smaller type having only a single beam, and established the efficiency of the 
new instrument. 

A collapsible double-waUed tent to protect the instrument during observations in 
the field has been designed and constructed in the workshops of the Science Museum. 
On completion of this, both the balances were tested in the open air near the laboratory. 
The readings were found to remain comparatively constant during the night, but were 
subject to considerable variations during the day, especially just after sunrise, and also 
at times when the temperature increased rapidly. An attempt to discriminate between 
the effects due to temperature fluctuations and solar radiation led to an investigation 
in the laboratory, in which the instruments were subjected to measured temperature 
changes in darkness. It was found that rapid fluctuations of temperature have a 
serious disturbing effect upon the stability of the balance beams. As an opportunity 
for a field test of the instruments occurred during the temperature tests, these latter 
were suspended, and will be continued in the near future. 

Field Tests. — At the request of the Shropshire Mines, Ltd., the two balances were 
transported by road to the Company's mining areas near Shrewsbury. Observations 
were made with the British instrument at seven stations in a region below which a 
mineral lode was being worked at a depth of 400 ft. From the dip and direction of this 
lode it was expected to come near the surface somewhere in the area surveyed. The 
results of the seven observations showed that a mass of heavy mineral existed below 
the area. The position, extent, and depth of this deposit were roughly determined, and 
it is understood that steps are being taken by the Company to verify these conclusions 
by drilling. 

Both instruments were then moved to another area, well beyond the actual mine 
workings, and observations were made with the object of determining whether mineral 
lodes existed in this area. In this region observations were taken at twenty-three 
stations with a few repetitions, two stations being occupied each night. The computa- 
tion of these results is not yet completed, but there are indications of an anomaly near 
one of the stations. A full account of the work in this locality will be published in the 
near future. 

Both areas surveyed in this test were of a hilly character, hitherto considered un- 
suitable for the employment of the Eotvos Balance, owing to the difficulty of calcu- 
lating gravity effects of the topographical features. The terrain in each case was of a 
fairly uniform slope, extending well beyond the area surveyed, so that the effects due 
to this slope could be assumed to act along a certain direction, viz. : the line of 
greatest slope. The effects due to the suspected lodes, of which the general direction 
was indicated by geological data, were at right angles to the topographical effects, 
and the latter could therefore be ignored. 

This test is considered to be of importance, not merely as it verifies the suitability 
of the balance for general field work, but also because it demonstrates the utility of 
such a survey in a region characteristic of the mineral areas throughout Great Britain. 
In such areas, flat ground, free from topographical disturbing effects, can scarcely 
ever be expected. 


Calculation of Mathematical Tables. — Report of Committee 
(Professor J. W. Nicholson, Chairman ; Dr. J. R. Airey, Secretary ; 
Dr. D. Wrinch-Nicholson, Mr. T. W. Chaundy, Professors L. N. G. 
FiLON, E. W. HoBSON, Mr. G. Kennedy, and Professors A. Lodge, 
A. E.H.Love, H. M. Macdonald, G. N. Watson, andk. G. Webster). 

As indicated in last year's Report, the following tables have been prepared for publi- 
cation for the Toronto Meeting : — 

(1) Tables of sin and cos 6 to fifteen places of decimals for values of in radians 
from 10-0 to 20-0 by intervals of 0-1 and from 20-0 to 50-0 by intervals of 0-5 radian, 
supplementing tables of these functions published in earlier reports of the Committee, 
viz., sin 6 and cos 6 to eleven places of decimals for values of 6 from 0000 to 1-600 by 
intervals of 0-001, with a short subsidiary table for purposes of interpolation, and Dr. 
Doodson's table giving one hundred values of sin and cos to fifteen places, ranging 
from 0-1 to 10-0 radians (Report, 1916) ; also sin and cos calculated to twenty- 
four places but reduced to fifteen to be uniform with the previous table for 0=0 to 
100 radians (Report 1923). 

(2) Tables of the Lommel -Weber functions 0.(,(x) andQi(a;) were calculated seven 
years ago with a view to their publication in the report of the Committee for 1917, but 
war conditions made this impossible. These functions are related to those of Struve 
which Professor Watson has recently given to seven places of decimals in the collection 
of mathematical tables in his ' Theory of Bessel functions.' 

(3) Tables of the Bessel-ClifEord* functions C„(a;) and Oi(x) which were computed 

from the relation Co(a;)=Jo(2 v x) and CAx)= — -i^"'^). These functions of zero and 

unit orders are of some interest, apart from their practical applications, and the con- 
struction of the tables did not present much difficulty. For functions of fractional 
order, however, the calculation from the well-known Bessel functions is troublesome 
and perhaps unnecessary. 

For next year's Report, it is suggested that the Association might undertake the 
publication of tables of the Bessel functions 3 ±,j^ Ix) to twelve places of decimals 


for x=\ to .r=20 : for positive orders, the calculations have been carried to the point 
where the first significant figure is in the thirteenth place, and for negative orders 
where the value of the function does not exceed unity : also tables of the Lommel- 
Weber functions, Qj(a;) andO_i(.r) to six places for values of the argument x from 0-00 
to 20-00 by intervals of 002, and similar tables of 3i(x) and J_\(x). The computation 
of tables of the Confluent HypergeometricfunctionfM(a. y. x), in particular for Y = i, 
is nearing completion. Tables of this kind have been found especially useful for the 
numerical solution of differential equations of the type 

+ ^^''^'^^ • dx + (^*'+'«*=+«)y=o 

and other equations occurring in physical and engineering problems. 

Sines and Cosines (6 in radians). 

From the tables of sin and cos published in last year's Report and the known 
values of sin a and cos a, where a =0-1 radian and 0-5 radian, 

sin 0-l = -f 0-09983 34166 468281 • 
cos 0-l =+0-99500 41652 780257: 
sin 0-5= -f 0-47942 55386 042030 
cos 0-5=-f 0-87758 25618 903727, 

the following table was constructed for intermediate values of by the relations 
sm (0-f a)=sia cos a+cos sin a, etc. For this purpose, the first hundred multiples 

* Sir C4eorge C4reenhill, Phil. .Mag., vol. 38, November 1919. 
t Phil. Mo;/., vol. 30, July 1918. 



of sin a and cos a were tabulated to eighteen places to facilitate tlie calculation of the 
products sin 9 . cos a, etc., and each sine or cosine obtained from the above formulae 
checked by previous results. 

These tables have been employed in calculating various functions from their 

asymptotic series. The functions J j(a;)= A/— .sin-rand J_j(x)= A/ .cos a; have 


been computed to sixteen places of decimals and functions of higher or lower order 
obtained from the recurrence relation 


Jv+i(-«)= • iTv(a;) — Jv_l(•^•)■ 

A considerable number of errors have been found in Lomrael's tables of Bessel functions 
of half-odd integral order and in the tables of Fresnel's Integrals. 

Sines and Cosines of Angles in Circular Measure. 


Sin 6 












































































+ 000442 







+ 0-10423 







+ 0-20300 







+ 0-29974 







H- 0-39349 







+ 0-48330 







+ 0-56828 







H- 0-64759 














+ 0-78607 







+ 0-84385 







+ 0-89320 







+ 0-93363 







+ 0-96473 














+ 0-99779 







+ 0-99943 











+ 0-23150 










+ 0-94486 







+ 0-90744 




+ 0-50866 



-f 0-86096 




+ 0-59207 



+ 0-80588 




+ 0-66956 



+ 0-74274 




+ 0-74037 







+ 0-80378 



+ 0-59492 




+ 0-85916 







+ 0-90595 










+ 0-33081 







+ 0-23494 




+ 0-99060 



H- 0-1.3673 




+ 0-99930 



+ 003715 



Sinea and Gosiues of Angles in Circular Measure — contd. 



Sin 6 


+ 0-99802 





















+ 0-93489 































































+ 0-30311 







+ 0-20646 

































































































































+ 0-02123 


73645 1 





+ 0-12094 







+ 0-21943 







+ 0-31574 



































+ 0-73199 














+ 0-85275 







+ 0-90064 


84769 ' 





+ 0-93952 







+ 0-96902 


39050 1 












+ 0-99877 







+ 0-99872 




+ 0-14987 







+ 0-24783 



+ 0-96880 




+ 0-34331 



+ 0-93922 







+ 0-90025 




+ 0-52306 







+ 0-605,53 

















+ 0-65964 




+ 0-81367 



+ 0-58132 











+ 0-91294 



+ 0-40808 




+ 0-99682 







Sinex and Cosines of Aiu/les in Oireiilar Measure — contd. 


Sin 6 
















































+ 0-42417 


















+ 0-35905 










+ 0-64691 




+ 0-97935 



+ 0-20213 







































-0-94] 03 
























































+ 0-87114 














+ 0-05748 

















































+ 0-29636 



+ 0-95507 




+ 0-71797 







+ 0-96379 



+ 0-26664 











+ 0-74511 



























































+ 0-99984 




+ 0-49488 














+ 0-99859 







+ 0-90178 



























































+ 0-96496 




Lommel-Weber Functions of Zero and Unit Orders. 

The function fi„(a;) defined by the integral _ I sin {x sin Q—nQ) dQ is related to 

^ J 

the function J„{x) and occurs in a number of problems in the difiraction of light J 
and in the propagation of electro-magnetic waves from a thin anchor ring. Lord 

Rayleigh's K(a') = 0„(.t;), j] K^ix) = x ( Q.i(x)+ ^ J, whilst Struve's function 

Ho(a:) = Q„(a:) and H,(a-) =-- r2,(x)+ ^ . 

The tables below were calculated from a; = 0-1 to x = 6-0 by intervals of 01 from 
the ascending series 

QJx) = ^ (x—^^ + ~— _„_:?l___. + . . . 
"^ ' TT \ 32 32-52 32 • 52- 72 ^ 

^^ ' TV V 3 ^ 32 • 5 32 • 52 • 7 

For values of x from 6-0 to 16-0, the asymptotic expansions were employed. 

n,{x) = - 


G,{x)-B„(x) I- 

where B,(x) =^-} +^ -^!l^ + 

X x-^ x^ x' 

and Qi(x) = -? i Gi(a;)-Bi(a;) '- 

■^ \ ) 

where BiX= -,1- -, + —.-- -, — + . . . 

X^ \ x^ x^ x^ 

and Go(a;) and Qi-^{x) are Neumann functions or Bessel functions of the second kind : 
tables of these functions have been computed for a;=0-00 to 16'00 and are given in the 
Report for 1912. 

If the calculation of B„(a;) and &x[x) from their asymptotic series is carried no 
further than the least term, these functions can only be found to three places of 
decimals, when x is 6. By the employment of the ' converging factor ' method, 
six place accuracy can be obtained even for this small value of the argument. The 
least term of the asymptotic series, multiplied by the corresponding converging factor, 
is equivalent to the divergent part of the series. 

For Bo(a;), if a;=2«,+a and . — 1 < a < 1, the converging factor is 

\ - ^ + ,V, (1 + 2a ^ a=) - \ (3 + 2a - 3a2) 
2 2a; 4a;- ^x^ 

+ \ (19 - 2a - 20a= + 2a3 + a*) . . . . 
8a.-« 11/ 

and for Bj(x), under the same conditions, 

-„\(13 -58a+24a2 + 2a'-a*) ... 

% H. Struve, Aniialen der PJnisik und Chemie, vol. 17, p. 1013. 

H. F. Weber, Vierteljahraschrift der Naturf. GeselL in ZiiricJi, vol. 24, p. 48. 
II Lord Rayleigh, Theory of Sound, vol. 2, pp. 164-5. 



Table of 'Converging Factors.' 


For B„(x) 

i ForBi{3:) 


0-504 : 



0-497 : 



0-490 : 

0-552 : 


0-483 : 

0-545 : 








0-463 : 



0-456 : 






0-443 : 

0-505 : 


0-437 : 


Intermediate values of Q^i^) and Qi(x) by intervals of 0-02 were then found by 
interpolation from central differences. The tables are given as calculated some years 
ago and are in substantial agreement with the values of the H„ and H^ functions in 
VVatson's ' Theory of Bessel Functions.' The colon : represents half a unit approxi- 
mately in the last place of decimals. 

Lommel-Weber D. Functions of Zero and Unit Orders. 

^ 1 









-0-636620 ! 










+ 0-025460 : 

-0-636280 : 


+ 0-443056 






+ 0-453489 



+0-060893 : 



+ 0-463802 



+ 0-063591 : 



+ 0-473994: 

-0-506497 : ' 


+ 0-076272 : 



+ 0-484061 

-0-500206 : 


+ 0-088933 



+ 0-494002 



+ 0101570 

-0-631196 : 


+ 0-503812 



+ 0-114179 : 



+ 0-513491 

-0-480585 : 


+ 0-126759 



+ 0-523035 

-0-473802 : 


+ 0139304: 

—0-626382 i 


+ 0-532442 



+ 0-151813 

-0-624443 : 



-0-459884 : 


+0-164281 : 






+ 0-176705 : 

-0-620069: i 







—0-617635 : 


+ 0-568656 






+ 0-577345 



+ 0-213683 : 



+ 0-685884 




-0^609354 : 


+ 0-594270 




+0-238056 : 



+ 0-602502 



+0-250149 : 



+ 0-610678 

-0-399860 I 


+ 0-262176: 

—0-599624 : 


+ 0-618496 

-0-391900 : 

, -44 

+0-274133 : 



+ 0-626254 


! -46 

^ 0-286018 

—0-592346 : 


+ 0-633850 



+ 0-297826 : 

-0-588473 : 





+ 0-309556 



+ 0-648550 



+ 0-321203 : 

-0-580265 : 


+ 0-655650 



+0-332765 : 

—0-575933 : 


+ 0-662582 

-0-342343 : 

: ^56 

+0-344239 : 

—0-671450 : 


+ 0-669343 

—0-333800 : 

1 ^58 

+0-355622 : 




: -0-325184 


+0-366911 : 




-0-316496: ! 





+ 0-688593 






-1- 0-694659 






+ 0-700549 


1 -68 

+ 0-411067 : 

-0-541480 : 


+ 0-706260 


Lommel-Weber CI Functions of Zero and Unit Orders — coiitd. 


X 1 







+ 0^71 1792 : 


2-60 1 

+0^705422 : 

+ 0-263747 : 






+ 0-270876 


+0-722313 : 

-0-253930 : 





+ 0-727301 

-0-244775 : 


+ 0-688961 

+ 0-284802 : 


+0^732104 : 

—0-235574 : 


+ 0-683196 : 



+0-736723 : 

-0-226331 : 


+ 0-677298 

+ 0-298276 


+0741157 : 



+ 0-671266 : 




-0-207727 : 


+ 0-665105 

+ 0-311281 



-0198372 : 



+0-317603 : 


+ 0^753340 

—0-188986 : 


+ 0-652401 : 

+ 0323803 : 


+0^757025 : 

-0-179572 : 


+0-645864 : 

+ 0-329880 


+ 0-760522 : 



+ 0-639207 : 

+0-335830 : 


+0^763830 : 

-0-160670 : 


+0-632432 : 

+ 0-341654 





+ 0-625542 






+ 0-618539 

+ 0-352913 : 




2-90 ' 

+ 0-611426 

+0-358346 : 



-0-122656 : 


+ 0-604206 

+ 0-363646 : 




, -94 

+ 0-596881 

+ 0-368812 





+ 0-589454 



+ 0-781666 : 

-0-094053 : 


+ 0-581928 

+ 0-378735 


+0-783452 . 

-0-084517 : 


+ 0-574306 

+ 0-383490 



—0-074985 : 


+ 0-566590 

+0-388105 : 


+ 0-786451 



+ 0-558783 

+0-392580 : 











+ 0-542907 

+ 0-401105 • 



—0-036955 : 


+ 0-534844 

+ 0-405153 






+ 0-409056 



-0018039 : 



+ 0-412815 


+ 0-790890 




. +0-416427 



+0-000778 : 








+ 0-493395 

: +0-423210 



+ 0-019476: 



: +0-426380 



+ 0-028773 : 



: +0-429401 



+ 0-038032 

j -26 

+ 0-467724 

: +0-432273 



+ 0-047249 


+ 0-459051 

: +0-434995 


+ 0-787522 

+ 0056422 



+ 0-437566 



: +0065548 


+ 0-441550 

+ 0-439987 



: +0-074625 


+ 0-432727 

: +0-442267 


+ 0-783318 

+ 0083649 


+ 0-423861 

+ 0-444376 



+ 0092618 


+ 0-414953 

: +0-446342 



: +0-101530 

1 3^40 

+ 0-406008 

+ 0-448157 



+ 0-110381 


+ 0-397028 

+ 0-449821 


1 +0-775198 

: +0-119169 


+ 0-388016 



, +0-772728 




: +0-462691 


! +0-770083 

: +0136546 


+ 0-369909 

: +0-453898 


+ 0-767266 

: +0145130 

, 3^50 




+ 0-764278 

: +0153640 


; +0-351712 

: +0-455855 


+ 0761121 

: +0^162075