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Full text of "Report of the eleventh meeting of the British Association for the Advancement of Science : held at Plymouth in July 1841 / British Association for the Advancement of Science. Meeting (1841 : Plymouth)"

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Leo^^7s-\ooi 



REPORT 



OF THE 



ELEVENTH MEETING 



OF THE 



BRITISH ASSOCIATION 



FOB THE 



ADVANCEMENT OF SCIENCE; 



HELD AT PLYMOUTH IN JULY 1841. 



LONDON: 

JOHN MURRAY, ALBEMARLE STREET. 

1842. 



PRINTED BY RICHARD AND JOHN E. TAYLOR, 
RED LION COURT, FLEflT STREET. 




CONTENTS. 



Page 

Objects and Rules of the Association v 

Officers and Council vii 

Places of Meeting and Officers from commencement viii 

Table of Council from commencement ix 

Officers of Sectional Committees, and Corresponding Members .... xi 

Treasurer's Account xii 

Reports, Researches, and Desiderata xiv 

Recommendations for Additional Reports and Researches in Science xix 

Synopsis of Money Grants xxiv 

Arrangements of the General Evening Meetings - . . . . xxv 

Address of the President xxvii 

REPORTS OF RESEARCHES IN SCIENCE. 

On the Present State of our Theoretical and Experimental Knowledge 
of the Laws of Conduction of Heat. By the Rev. Philip Kelland, 
M.A., F.R.SS. Lond. and Edin., Professor of Mathematics in the Uni- 
versity of Edinburgh, late Fellow of Queen's College, Cambridge . . 1 

Report on Poisons. By G. L. Roupell, M.D., F.R.S 26 

Report on Discussions of Bristol Tides, performed by Mr. Bunt under 
the direction of the Rev. W. Whewell, F.R.S 30 

Report on the Discussion of Leith Tide Observations, executed by 
Mr. D. Ross, of the Hydrographer's Office, Admiralty, under the 
direction of the Rev. W. Whewell 33 

Upon the working of Whewell's Anemometer at Plymouth during the 
past year. By W. S. Harris, Esq., F.R.S 36 

Report of a Committee, consisting of Sir J. F. W. Herschel, Bart., 
Mr. Whewell, the Very Rev. the Dean of Ely, Professor Lloyd, 
and Lieut.-Colonel Sabine, appointed for the purpose of superintend- 
ing the scientific co-operation of the British Association in the 
system of Simultaneous Observations in Terrestrial Magnetism and 
Meteorology 38 

Reports of Committees appointed to provide Meteorological Instruments 
for the use of M. Agassiz and Mr. M'Cord 41 

Report of a Committee, consisting of Sir J. Herschel only, to super- 
intend the reduction of Meteorological Observations.— July 1841 . , 42 



IV CONTENTS. 

Page 
Report of a Committee, consisting of Sir J. Herschel, Mr. Whewell, 
and Mr. Baily, for revising the Nomenclature of tlie Stars 44 

Report of a Committee appointed at the Glasgow Meeting of the British 
Association in September ISiO, for obtaining Instruments and Re- 
gisters to record shocks of Earthquakes in Scotland and Ireland 46 

Report of tlie Committee for making Experiments on the Preservation 
of Vegetative Powers in Seeds 50 

On Inquiries into the Races of Man, by Dr. Hocgkin 52 

Report of the Committee appointed to report how far the Desiderata in 
our knowledge of the Condition of the Upper Strata of the Atmo- 
sphere may be supplied by means of Ascents in Balloons or other- 
wise, to ascertain the probable Expense of such Experiments, and to 
draw up Directions for Observers in such circumstances 55 

Report on British Fossil Reptiles. By Richard Owen, Esq., F.R.S.. 
F.G.S., &c. &c 60 

Reports on the Determination of the Mean Value of Railway Constants 205 

Second and concluding Report on the Determination of the Mean Value 
of Railway Constants. By Dionysius Lardner, LL.D., F.R.S., &c. 205 

Report on Railway Constants. By Edward Woods 247 

Report of a Committee appointed at the Tenth Meeting of the Associa- 
tion, on the Construction of a Constaut Indicator for Steam-Engines. 
Members of the Committee, the Rev. Professor Moseley, M.A., 
F.R.S., Eaton Hodgkinson, Esq., F.R.S., J. Enys, Esq 307 

Provisional Reports, and Notices of Progress in Special Researches en- 
trusted to Committees and Individuals 325 

Varieties of Humaii Race. — Queries respecting the Human Race, to be 
addressed to Travellers and others. Drawn up by a Committee of 
the British Association for the Advancement of Science, appointed in 
1839 332 

Observations made at the Magnetic Observatory at Toronto, during a 
remarkable Magnetic Disturbance on the 25th and 26th of Septem- 
ber, 1841 ; with Postscripts, containing the Observations of the same 
Disturbance made at the Magnetic Observatories of Trevandrum, St. 
Helena, and the Cape of Good Hope , 340 



OBJECTS AND RULES 



OF 



THE ASSOCIATION. 



OBJECTS. 

The Association contemplates no interference with the ground occupied by 
other Institutions. Its objects are, — To give a stronger impulse and a more 
systematic direction to scientific inquiry, — to promote the intercourse of those 
who cultivate Science in different parts of the British Empire, with one an- 
other, and with foreign philosophers, — to obtain a more general attention to 
the objects of Science, and a removal of any disadvantages of a public kind 
which impede its progress. 



RULES. 

MEMBERS. 

All Persons -who have attended the first Meeting shall be entitled to be- 
come Members of the Association, upon subscribing an obligation to conform 
to its Rules. 

The Fellows and Members of Chartered Literary and Philosophical So- 
cieties publishing Transactions, in the British Empire, shall be entitled, in 
like manner, to become Members of the Association. 

The Officers and Members of the Councils, or Managing Committees, of 
Philosophical Institutions, shall be entitled, in like manner, to become Mem- 
bers of the Association. 

All Members of a Philosophical Institution, recommended by its Council 
or Managing Committee, shall be entitled, in like manner, to become Mem- 
bers of the Association. 

Persons not belonging to such Institutions shall be elected by the General 
Committee or Council, to become Members of the Association, subject to the 
approval of a General Meeting. 

SUBSCRIPTIONS. 

The amount of the Annual Subscription shall be One Pound, to be paid in 
advance upon admission ; and the amount of tlie composition in lieu thereof, 
Five Pounds. 

An admission fee of One Pound is required from all Members elected as 
Annual Subscribers, after the Meeting of 1839, in addition to their annual 
subscription of One Pound. 

The volume of Reports of the Association will be distributed gratuitously 
to every Annual Subscriber who has actually paid the Annual Subscription 
for the year to whicli the volume relates, and to all those Life Members wlio 
shall have paid Two Pounds as a Book Suhscription. 

Subscriptions shall be received by the Treasurer or Secretaries. 

If the Annual Subscription of any Member shall have been in arreur for 
184.1. b 



VI RULES OP THE ASSOCIATION. 

two years, and shall not be paid on proper notice, he shall cease to be a 
Member. 

MEETINGS. 

The Association shall meet annually, for one week, or longer. The place 
of each Meeting shall be appointed by the General Committee at the previous 
Meeting ; and the Arrangements for it shall be entrusted to the Officers of 
the Association. 

GENERAL COMMITTEE. 

The General Committee shall sit during the week of the Meeting, or longer, 
to transact the business of the Association. It shall consist of the following 
persons : — 

1. Presidents and Officers for the present and preceding years, with au- 
thors of Reports in the Transactions of the Association. 

2. Members who have communicated any Paper to a Philosophical Society, 
Avhich has been printed in its Transactions, and which relates to such subjects 
as are taken into consideration at the Sectional Meetings of the Association. 

3. Office-bearers for the time being, or Delegates, altogether not exceeding 
three in number, from any Philosophical Society publishing Transactions. 

4. Office-bearers for the time being, or Delegates, not exceeding three, 
from Philosophical Institutions established in the place of Meeting, or in any 
place where the Association has formerly met. 

5. Foreigners and other individuals whose assistance is desired, and who 
are specially nominated in writing for the Meeting of the year by the Presi- 
dent and General Secretaries. 

6. The Presidents, Vice-Presidents, and Secretaries of the Sections are ex 
officio members of the General Committee for the time being. 

SECTIONAL COMMITTEES. 

The General Committee shall appoint, at each Meeting, Committees, con- 
sisting severally of the Members most conversant with the several branches 
of Science, to advise together for the advancement thereof. 

The Committees shall report what subjects of investigation they would par- 
ticularly recommend to be prosecuted during the ensuing year, and brought 
under consideration at the next Meeting. 

The Committees shall recommend Reports on the state and progress of par- 
ticular Sciences, to be drawn up from time to time by competent persons, for 
the information of the Annual Meetings. 

COMMITTEE OF RECOMMENDATIONS. 

The General Committee shall appoint at each Meeting a Committee, which 
shall receive and consider the Recommendations of the Sectional Committees, 
and report to the General Committee the measures which they would advise 
to be adopted for the advancement of Science. 

All Recommendations of Grants of Money, Requests for Special Re- 
searches, and Reports on Scientific Subjects, shall be submitted to the Com- 
mittee of Recommendations, and not taken into consideration by the General 
Committee unless previously recommended by the Committee of Recommen- 
dations. 

LOCAL COMMITTEES. 

Local Committees shall be formed by the Officers of the Association to 
assist in making arrangements for the Meetings. 

Committees shall have the power of adding to their numbers those Mem- 
bers of the Association whose assistance they may desire. 



RULES OP THE ASSOCIATION. VU 

OFFICERS. 

A President, two or more Vice-Presidents, one or more Secretaries, and a 
Treasurer, shall be annually appointed by the General Committee. 

COUNCIL. 

In the intervals of the Meetings, the affairs of the Association shall be 
managed by a Council appointed by the General Committee. The Council 
may also assemble for the despatch of business during the week of the Meeting. 

PAPERS AND COMMUNICATIONS. 

The Author of any paper or communication shall be at liberty to reserve 
his right of property therein. 

ACCOUNTS. 

The Accounts of the Association shall be audited annually, by Auditors 
appointed by the Meeting. 



OFFICERS AND COUNCIL, 1841—42. 

Trustees {permanent). — Francis Baily, Esq. R. I. Murchison, Esq. John 
Taylor, Esq. 

President. — Rev. Professor Whewell, F.R.S., V.P.G.S. 

Vice-Presidents. — The Earl of Mount Edgecumbe. The Earl of Morley. 
Lord Eliot, M.P. Sir C. Lemon, Bart. Sir T. D. Acland, Bart. 

President Elect.' — Lord Francis Egerton. 

Vice-Preside7its Elect. — John Dalton, D.C.L., F.R.S. Rev. Prof. Sedg- 
wick, F.R.S. C. Henry, M.D., F.R.S. Sir Benjamin Heywood, Bart. Hon. 
and Rev. William Herbert, F.L.S. (Dean of Manchester). 

General Secretaries. — R.I. Murchison, Esq., F.R.S. Colonel Sabine, F.R.S. 

Assistant General Secretary. — John Phillips, Esq., F.R.S., York. 

Secretaries for the Manchester Meeting in 1842. — Peter Clare, Esq. H. 
Fleming, M.D. James Heywood, Esq. 

General Treasurer. — John Taylor, Esq., F.R.S., &c. 2 Duke Street, Adel- 
phi, London. 

Treasurer to the Meeting in 1842. — 

Council. — G. B. Airy, Esq. H. T. De la Beche, Esq. Robert Brown, 
Esq. Rev. Dr. Buckland. Sir David Brewster. Dr. Daubenj% Sir Philip 
Egerton, Bart. Professor Forbes. Professor T. Graham. G. B. Greenough, 
Esq. Leonard Horner, Esq. W. J. Hamilton, Esq. Robert Hutton, Esq. 
Rev. W. V. Harcourt. Rev. Professor Lloyd. Rev. Dr. Peacock (Dean 
of Ely). The Marquis of Northampton. Rev. Dr. Robinson. Dr. Roget. 
Dr. Richardson. Sir John Robison. George Rennie, Esq. H. E. Strick- 
land, Esq. Lieut.-Col. Sykes. Professor Wheatstone. 

Local Treasurers.- — Dr. Daubeny, Oxford. Professor Henslow, Cam- 
bridge. Dr. Orpen, Dublin. Charles Forbes, Esq., Edinburgh and Glas- 
gow. William Gray, jun., Esq., York. William Sanders, Esq., Bristol. 
Samuel Turner, Esq., Liverpool. Rev. John James Tayler, Manchester. 
James Russell, Esq., Birmingham. William Hutton, Esq., Newcastle-on- 
Tyne. Henry WooUcombe, Esq., Plymouth. 

Auditors. — William Yarrell, Esq. Leonard Horner, Esq. Robert Hut- 
ton, Esq. 

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MEMBERS OF COUNCIL. 



IX 



General Secretaries. -< 

General Treasurer. 

Trustees (permanent). 

Assistant General 
Secretary. 



.1832—1836. 
.1835. 

.1836—1841. 

.1837, 1838. 

.1839, 1841. 

.1832—1841. 

(Resigned.) 



-1841. 



II. Table showing the Members of Council of the British Association from 
its Commencement, in addition to Presidents, Vice-Presidents, and Local 
Secretaries. 

f Rev. Wm. Vernon Harcourt, F.R.S., &c. 

Francis Baily, V.P. and Treas. R.S 

R. I. Murchison, F.R.S., F.G.S 

Rev. G. Peacock, F.R.S., F.G.S., &c. .. 

Lieut.-Colonel Sabine, V.P.R.S ,. 

John Taylor, F.R.S., Treas. G.S., &c 

•Charles Babbage, F.R.SS.L.&E., &c 
R. I. Murchison, F.R.S.. &c. 
■ John Taylor, F.R.S., &c. 
.Francis Baily, F.R.S. 

|Professor Phillips, F.R.S. , &c 1832— 

Members of Council. 

G. B. Airy, F.R.S. , Astronomer Royal 1834, 1835, 1841, 

Neil Arnott, M.D '...' 1838, 1839,1840. 

Francis Baily, V.P. and Treas. R.S 1837—1839. 

H. T. De la Beche, F.R.S 1841. 

George Bentham, F.L.S 1834, 1835. 

Robert Brown, D.C.L., F.R.S 1832, 1834, 1835, 1838—1841 

Sir David Brewster, F.R.S., &c 1832, 1841. 

Mark I. Brunei, F.R.S., &c 1832. 

Rev. Professor Buckland, D.D., F.R.S., &c. 1833, 1835, 1838—1841. 

The Earl of Burlington 1838, 1839. 

Rev. T. Chalmers, D.D., Prof, of Divinity, 

Edinburgh 1833. 

Professor Clark, Cambridge 1838. 

Professor Christie, F.R.S., &c 1833 — 1837. 

William Clift, F.R.S., F.G.S 1832—1835. 

J. C. Colquhoun, Esq 1840. 

John Corrie, F.R.S., &c 1832. 

Professor Daniell, F.R.S 1836, 1839. 

Dr. Daubeny 1838 — 1841. 

J. E. Drinkwater 1834, 1835. 

Sir Philip G. Egerton, Bart 1840, 1841. 

The Earl Fitzwilliam, D.C.L., F.R.S., &C....1833. 
Professor Forbes, F.R.SS.L. &E., &c. 
Davies Gilbert, D.C.L., V.P.R.S., &c. , 
Professor R. Graham, M.D., F.R.S.E. . 

Professor Thomas Graham, F.R.S , 

John Edward Gray, F.R.S., F.L.S., &c. 

Professor Green, F.R.S.. F.G.S 

G. B. Greenough, F.R.S., F.G.S 

Henry Hallam, F.R.S., F.S.A., &c 

Sir William R. Hamilton, Astron. Royal of 

Ireland 1832, 

W.J. Hamilton, Sec. G.S 1840, 

Rev. Prof. Henslow, M.A., F.L.S., F.G.S. .1837. 
Sir John F. W. Herschel, F.R.SS. L. & E., 

F.R.A.S., F.G.S., &c 1832. 

Thomas Hodgkin, M.D 1833—1837, 1839, 1840. 

Prof. Sir W. J. Hooker, LL.D., F.R.S., &c. 1832. 

Leonard Horner, F.R.S 1841. 

Rev. F. W. Plope, M.A., F.L.S 1837. 

Robert Hutton, F.G.S., &c 1836, 1838, 1839, 1840, 1841 

Professor R. Jameson, F.R.SS. L. & E 1833. 

Rev. Leonard Jenyns 1838. 

H. B. Jerrard, Esq 1840. 



....1832, 1841. 
....1832. 
....1837. 

....1838, 1839, 1840, 1841. 
...1837—1839, 1840. 
....1832. 

....1832—1839, 1840, 1841. 
....1836. 



1833, 1836. 
1841. 



MEMBBRS OF COUNCIL.. 

Dr. R. Lee 1839. 

Sir Charles Lemon, Bart 1838, 1839. 

Rev. Dr. Lardner 1838, 1839. 

Professor Lindley, F.R.S., F.L.S., &c 1833, 1836. 

Rev. Professor Lloyd, D.D 1832, 1833, 1841. 

J. W. Lubbock, F.R.S., F.L.S., &c., Vice- 

Chancellor of the University of London ...1833—1836, 1838, 1839. 

Rev. Thomas Luby 1832. 

Charles Lyell, jun., F.R.S 1838, 1839, 1840. 

William Sharp MacLeay, F.L.S 1837. 

Professor Miller, F.G.S 1840. 

Professor Moseley 1839, 1840. 

Patrick Neill, LL.D., F.R.S.E 1833. 

The Marquis of Northampton, P.R.S 1840, 1841. 

Richard Owen, F.R.S., F.L.S 1836, 1838, 1839. 

Rev. George Peacock, M.A., F.R.S., &c. ...1832, 1834, 1835, 1839, 1840, 1841. 

E. Pendarves, Esq 1840. 

Rev. Professor Powell, M.A., F.R.S., &c. ...1836, 1837, 1839, 1840. 

J. C. Prichard, M.D., F.R.S., &c 1832. 

George Rennie, F.R.S 1833—1835, 1839, 1841. 

Sir John Rennie 1838. 

Dr. Richardson, F.R.S 1841. 

Rev. Professor Ritchie, F.R.S 1833. 

Rev. T. R. Robinson, D.D 1841. 

Sir John Robison, Sec. R.S.E 1832, 1836, 1841. 

P. M. Roget,M.D., Sec. R.S., F.G.S., &c.... 1834— 1837, 1841. 

Lieut.-Colonel Sabine , 1838. 

Lord Sandon 1840. 

Rev.WilliamScoresby,B.D., F.R.SS.L.&E.1832. 

H.E. Strickland, Esq., F.G.S 1840, 1841. 

Lieut.-Col. W. H. Sykes, F.R.S., F.L.S., &C.1837— 1839, 1840, 1841. 

H. Fox Talbot, Esq., F.R.S 1840. 

Rev. J. J. Tayler, B.A., Manchester 1832. 

Professor Traill, M.D 1832, 1833. 

N. A. Vigors, M.P.,D.C.L., F.S.A., F.L.S. ..1832, 1836, 1840. 

James Walker, Esq., P.S.C.E 1840. 

Captain Washington, R.N 1838, 1839, 1840. 

Professor Wheatstone 1838 — 1841. 

Rev. W. Whewell 1838, 1839. 

William Yarrell, F.L.S 1833 — 1836. 

Secretaries to ^Aef Edward Turner, M.D., F.R.SS. L. & E. 1832—1836. 
Council. t James Yates, F.R.S., F.L.S., F.G.S. 1831—1840. 



OFFICERS OP SECTIONAL COMMITTEES. xi 

OFFICERS OF SECTIONAL COMMITTEES AT THE 
PLYMOUTH MEETING. 

SECTION A. — MATHEMATICAL AND PHYSICAL SCIENCE. 

President. — Rev. Professor Lloyd, F.R.S. 

Vice-Presidents — Rev. T. R. Robinson, D.D. Professor Christie, Sec. R.S. 
Secretary. — Professor Stevelly, M.A. 

SECTION B. CHEMISTRY AND MINERALOGY. 

President. — Dr. Daubeny, F.R.S. 

Vice-President.' — Colonel Yorke. 

Secretaries, — John Prideaux. Robert Hunt. W. M. Tweedy. 

SECTION C. GEOLOGY AND PHYSICAL GEOGRAPHY. 

President.— U. T. De la Beche, F.R.S., &c. 

Vice-Presidents. — Rev. W. D. Conybeare, F.R.S. Professor Sedgwick, 
F.R.S. Dr. Buckland, F.R.S. Marquis of Northampton, Pres. R.S. 

Secretaries. — W. J. Hamilton, Sec. G.S. Edward Moore, M.D. R. Hut- 
ton, F.G.S. 

SECTION D. ZOOLOGY AND BOTANY. 

President. — John Richardson, M.D., F.R.S., &c. 

Vice-Presidents. — Richard Owen, F.R.S. Professor Henslow, F.L.S., 
F.G.S. J. E. Gray, F.R.S. 

Secretaries — E. Lankester, M.D., F.L.S. R. Patterson. J. Couch, F.L.S. 

SECTION E. MEDICAL SCIENCE. 

President.—?. M. Roget, M.D., Sec. R.S. 
Vice-Presidents. — P. Miller, M.D. Sir D. Dickson. 
Secretaries — John Butter, M.D. J. Fuge. Richard S. Sargent, M.D. 

SECTION F. — STATISTICS. 

President. — Lieut.-Col. Sykes, F.R.S. 

Vice-Presidents. — Professor A. Quetelet, F.R.S., F.M.S.S. Viscount 
Ebrington, M.P., F.S.S. Leonard Horner, F.R.S. Rev. W. S. Hore. 

Secretaries.— Rev. E. Byrth, D.D., F.A.S. Rev. R. Luney, M.A. R, W. 
Rawson. 

SECTION G. MECHANICAL SCIENCE. 

President. — John Taylor, Esq., F.R.S., &c. 

Vice-Presidents — Professor Moseley. J. S. Enys. J. M. Rendel. 

Secretaries. — Henry Chatfield. Thomas Webster. 

CORRESPONDING MEMBERS. 

Professor Agassiz, Neufchatel. M. Arago, Secretary of the Institute, 
Paris. A. Baclie, Principal of Girard College, Philadelphia. Pi-ofessor Ber- 
zelius, Stockholm. Professor H. von Boguslawski, Breslau. Professor De 
la Rive, Geneva. Professor Dumas, Paris. Professor Ehrenberg, Berlin. 
Professor Encke, Berlin. Baron Alexander von Humboldt, Berlin. M. 
Jacobi, St. Petersburg!!. Dr. Lamont, Munich. Professor Lieblg, Giessen. 
Professor Link, Berlin. Professor Oersted, Copenhagen. M. Otto, Breslau. 
Jean Plana, Astronomer Royal, Turin. M. Quetelet, Brussels. Professor 
C. Ritter, Berlin. Professor Schumacher, Altona. 



BRITISH ASSOCIATION FOR THE 



TREASURER'S ACCOUNT from 



RECEIPTS. 

£ s. d. 

Balance in hand from last year's Account 

Contributions from Members at Glasgow and since 790 

Subscriptions Ditto Ditto 1843 



Compositions for Books (future publications) 

Dividend on ^5000 3 per cent. Consols. 6 months, to 1 

January 1841 J 

Ditto £6000 ditto 6 months, to July last 90 



75 



Received on account of Sale of Reports, viz. 

1st vol., 2nd Edition 11 10 6 

2ndvol 10 4 2 

3rd vol 16 1 

4th vol 15 9 9 

5th vol 21 14 7 

6th vol 32 1 2 

7th vol 56 17 

Lithographs 8 



£ s. d. 
309 II 6 



2633 
100 








165 



6 2 



£3371 17 8 



WILLIAM YARRELL, I 

ROBT. HUTTON, | Auditors. 



ADVANCEMENT OF SCIENCE. 



£ s. (l. 
898 15 
300 



153 4 8 
239 13 2 
177 10 



31st August 1840 to the 24th July IS^l. 

PAYMENTS. 

cG s. d. 

Purchase of £1000, 3per cent. Consols 

Expenses of Meeting at Glasgow 

Balance of Account for printing, &c. Nintli Report 144 1 11 

Paid on account of Tentli Report 9 2 9 

Disbursements by General and Local Treasurers, Advertising, 1 
Sundry Printing, and publishing Reports J 

Salaries to Assistant Secretary, Accountant, and Clerk 

Grants to Committees for Scientific piu-poses, viz. — for 

Experiments on Waves 1839 

Reduction of Stars in Histoire Celeste „ 

Meteorology, &c. Subteiranean Temperature „ 

Acrid Poisons „ 

Experiments on Veins and Absorbents „ 

Marine Zoology „ 

Fossil Reptiles „ 

Foreign Scientific Memoirs „ 

Inquiries into the races of Men „ 

Anemometer at Edinburgh ,, 

Forms of Vessels ,, 

Skeleton Maps „ 

Radiate Animals „ 

Tabulating Observations on Subterranean Temperature, 1 

J " 



and Plate 



Actinometers 

Registering Eartliquake Shocks 

Mud in Rivers 

Mountain Barometers 

Stars in Histoire Celeste 

Lacaille's Stars 

Nomenclature of Stars 

British Association Catalogue of Stars 

Action of Water on Iron 

Meteorological Observations at Inverness, &c 

Reduction of Meteorological Observations 

Foreign Scientific Memoirs 

Railway Sections 

Meteorological Observations and Anemometers at Plymouth 

Magnetical Co-operation 

Fishes of Old Red Sandstone 

Tides at Leith 

Anemometer at Edinburgh 



1840 



30 

50 

8 8 
6 
3 

15 12 8 

50 

50 18 6 

5 

60 
193 12 

20 

2 

9 C 3 

10 
17 7 

5 

6 18 6 
135 

79 5 

17 19 6 

40 

50 

20 

25 

11 2 
38 1 
55 

61 18 8 
100 

50 

9 1 10 



503 17 5 



731 13 6 



Balance in hands of Bankers > 218 5 1 

Do Treasurer and Local Treasurers 148 18 10 



- 367 3 11 
£3371 17 8 



British Association Property, 28th July, 1841. 

Balance of Cash in hand £367 3 11 

£6000 in 3 per cent. Consols, in the names of the Trustees, valued at 89| 5385 

Stock of Books on hand, estimated at 1203 6 



£6955 9 11 



Xiv REPORT — 1841. 

The following Reports on the Progress and Desiderata of different branches 
of Science have been drawn up at the request of the Association, and 
printed in its Transactions. 

1831-32. 

On the progress of Astronomy during the present century, by G. B. Airy, 
M.A., Astronomer Royal. 

On the state of our knowledge respecting Tides, by J. W. Lubbock, M.A., 
Vice-President of the Royal Society. 

On the recent progress and present state of Meteorology, by James D. 
Forbes, F.R.S., Professor of Natural Philosophy, Edinburgh. 

On the present state of our knowledge of the science of Radiant Heat, by 
the Rev. Baden Powell, M.A., F.R.S., Savilian Professor of Geometry, 
Oxford. 

On Thermo-electricity, by the Rev. James Gumming, M.A., F.R.S., Pro- 
fessor of Chemistry, Cambridge. 

On the recent progress of Optics, by Sir David Brewster, K.C.G., L.L.D., 
F.R.S., &c. 

On the recent progress and present state of Mineralogy, by the Rev. 
William Whewell, M.A., F.R.S. 

On the progress, actual state, and ulterior prospects of Geology, by the 
Rev. William Conybeare, M.A., P.R.S., V.P.G.S., &c. 

On the recent progress and present state of Chemical Science, by J. F. W. 
Johnston, A.M., Professor of Chemistry, Durham. 

On the application of Philological and Physical researches to the History 
of the Human species, by J. C. Prichard, M.D., F.R.S., &c. 

1833. 

On the advances which have recently been made in certain branches of 
Analysis, by the Rev. G. Peacock, M.A., F.R.S., &c. 

On the present state of the Analytical Theory of Hydrostatics and Hydro- 
dynamics, by the Rev. John Challis, M.A., F.R.S., &c. 

On the state of our knowledge of Hydraulics, considered as a branch of 
Engineering, by George Rennie, F.R.S., &c. (Parts I. and II.) 

On the state of our knowledge respecting the Magnetism of the Earth, by 
S. H. Christie, M.A., F.R.S., Professor of Mathematics, Woolwich. 

On the state of our knowledge of the Strength of Materials, by Peter 
Barlow, F.R.S. 

On the state of our knowledge respecting Mineral Veins, by John Taylor, 
F.R.S., Treasurer G.S., &c. 

On the Physiology of the Nervous System, by William Charles Henry, 
M.D. 

On the recent progress of Physiological Botany, by John Lindley, F.R.S., 
Professor of Botany in the University of London. 

1834. 

On the Geology of North America, by H. D. Rogers, F.G.S. 

On the philosophy -of Contagion, by W. Henry, M.D., F.R.S. 

On the state of Physiological Knowledge, by the Rev. Wm. Clark, M.D., 
F.G.S., Professor of Anatomy, Cambridge. 

On the state and progress of Zoology, by the Rev. Leonard Jenyns, M.A., 
F.L.S., &c. 

On the theories of Capillary Attraction, and of the Propagation of Sound 
as aifected by the Development of Heat, by the Rev. John Challis, M.A., 
F.R.S., &c. 



RESEARCHES IN SCIENCE. XV 

On the state of the science of Physical Optics, by the Rev. H. Lloyd, M.A., 
Professor of Natural Philosophy, Dublin, 

1835. 

On the state of our knowledge respecting the application of Mathematical 
and Dynamical principles to Magnetism, Electricity, Heat, &c., by the Rev. 
Wm. Whewell, M.A., F.R.S. 

On Hansteen's researches in Magnetism, by Captain Sabine, F.R.S. 

On the state of Mathematical and Physical Science in Belgium, by M. 
Quetelet, Director of the Observatory, Brussels. 

1836. 

On the present state of our knowledge with respect to Mineral and Thermal 
Waters, by Charles Daubeny, M.D., F.R.S., M.R.I.A., &c., Professor of 
Chemistry and of Botany, Oxford. 

On North American Zoology, by John Richardson, M.D., F.R.S., &c. 

Supplementary Report on the Mathematical Theory of Fluids, by the Rev. 
J. Challis, Plumian Professor of Astronomy in the University of Cambridge. 

183Y. 

On the variations of the Magnetic Intensity observed at diflPerent points of 
the Earth's surface, by Major Edward Sabine, R.A., F.R.S. 

On the various modes of Printing for the use of the Blind, by the Rev. 
William Taylor, F.R.S. 

On the present state of our knowledge in regard to Dimorphous Bodies, 
by Professor Johnston, F.R.S. 

On the Statistics of the Four CoUectorates of Dukhun, under the British 
Government, by Col. Sykes, F.R.S. 

1838. 

Appendix to Report on the variations of Magnetic Intensity, bv Major 
Edward Sabine, R.A., F.R.S. 

1839. 

Report on the present state of our knowledge of Refractive Indices for 
the Standard Rays of the Solar Spectrum in different media, by the Rev. 
Baden Powell, M.A., F.R.S., F.G.S., F.R.Ast.S., Savilian Professor of Geo- 
metry, Oxford. 

Report on the distribution of Pulmoniferous MoUusca in the British Isles, 
by Edward Forbes, M.W.S., For. Sec. B.S. 

Report on British Fossil Reptiles, Part t., by Richard Owen, Esq., F.R.S., 
F.G.S., &c. 

1840. 

Report on the recent progress of discovery relative to Radiant Heat, sup- 
plementary to a former Report on the same subject inserted in the first 
volume of the Reports of the British Association for the Advancement of 
Science, by the Rev. Baden Powell, M.A., F.R.S., F.R.Ast.S., F.G.S., Savilian 
Professor of Geometry in the University of Oxford. 

Supplementary Report on Meteorology, by James D. Forbes, Esq., F.R.S., 
Sec. R.S. Ed., Professor of Natural Philosophy in the University of Edin- 
burgh. 

1841. 

Report on the conduction of Heat, by Professor Kelland, F.R.S., &c. 

Report on the state of our knowledge of Fossil Reptiles, Part II., by Pro- 
fessor R. Owen, F.R.S. 



Xvi REPORT — 1841. 

The following Reports of Researches tindertalten at the request of the Associa- 
tion Jutve been publis/ted, viz. 

1835. 

On the comparative measurement of the Aberdeen Standard Scale, by 
Francis Baily, Treasurer R.S., &c. 

On Impact upon Beams, by Eaton Hodgkinson. 

Observations on the Direction and Intensity of the Terrestrial Magnetic 
Force in Ireland, by the Rev. H. Lloyd, Capt. Sabine, and Capt. J. C. Ross. 

On the phaenomena usually referred to the Radiation of Heat, by H. 
Hudson, M.D. 

Experiments on Rain at different Elevations, by Wm. Gray, Jan., and 
Professor Phillips (Reporter). 

Hourly observations of the Thermometer at Plymouth, by W. S. Harris. 

On the Infra-orbital Cavities in Deers and Antelopes, by A. Jacob, M.D. 

On the Effects of Acrid Poisons, by T. Hodgkin, M.D. 

On the Motions and Sounds of the Heart, by the Dublin Sub-Committee. 

On the Registration of Deaths, by the Edinburgh Sub- Committee. 

1836. 

Observations on the Direction and Intensity of the Terrestrial Magnetic 
Force in Scotland, by Major Edward Sabine, R.A., F.R.S., &c. 

Comparative view of tlae more remarkable Plants which characterize the 
Neighbourhood of Dublin, the Neighbourhood of Edinburgh, and the South- 
west of Scotland, &c. ; drawn up for the British Association by J. T. Mackay, 
M.R.I.A., A.L.S., &c. ; assisted by Robert Graham, Esq., M.D., Professor of 
Botany in the University of Edinburgh. 

Report of the London Sub- Committee of the Medical Section of . the 
British Association on the Motions and Sounds of the Heart. 

Report of the Dublin Committee on the Pathology of the Brain and 
Nervous System. 

Account of the Recent Discussions of Observations of the Tides which 
have been obtained by means of the grant of money which was placed at the 
disposal of the Author for that purpose at the last meeting of the Association, 
by J. W. Lubbock, Esq. 

Observations for determining the Refractive Indices for the Standard Rays 
of the Solar Spectrum in various media, by the Rev. Baden Powell, M.A., 
F.R.S., Savilian Professor of Geometry in the University of Oxford. 

Provisional Report on the Communication between the Arteries and 
Absorbents, on the part of the London Committee, by Dr. Hodgkin. 

Report of Experiments on Subterranean Temperature, under the direction 
of a Committee, consisting of Professor Forbes, Mr. W. S. Harris, Professor 
Powell, Lieut.-Colonel Sykes, and Professor Phillips (Reporter). 

Inquiry into the validity of a method recently proposed by George B. 
Jerrard, Esq., for Transforming and Resolving Equations of Elevated Degrees ; 
undertaken, at the request of the Association, by Professor Sir W.R. Hamilton. 

1837. 

Account of the Discussions of Observations of the Tides which have been 
obtained by means of the grant of money which was placed at the disposal 
of the Author for that purpose at the last Meeting of the Association, by J. 
W. Lubbock, Esq., F.R.S. 

On the difference between the Composition of Cast Iron produced by the 
Cold and the Hot Blast, by Thomas Thomson, M.D., F.R.SS. L. & E., &c.. 
Professor of Chemistry, Glasgow. 

On the Determination of the Constant of Nutation by the Greenwich Ob- 



RESEARCHES IN SCIENCE. XVll 

servations, made as commanded by the British Association, by the Rev. T. 
R. Robinson, D.D. 

On some Experiments on the Electricity of Metallic Veins, and the Tem- 
perature of Mines, by Robert Were Fox. 

Provisional Report of the Committee of the Medical Section of the British 
Association, appointed to investigate the Composition of Secretions, and the 
Organs producing them. 

Report from the Committee for inquiring into the Analysis of the Glands, 
&c. of the Human Body, by G. O. Rees, M.D., F.G.S. 

Second Report of the London Sub-Committee of the Medical Section of 
the British Association, on the Motions and Sounds of the Heart. 

Report from the Committee for making experiments on the Growth of 
Plants under Glass, and without any free communication with the outward 
air, on the plan of Mr. N. I. Ward, of London. 

Report of the Committee on Waves, appointed by the British Association 
at Bristol in 1836, and consisting of Sir John Robison, K.H., Secretary of 
the Royal Society of Edinburgh, and John Scott Russell, Esq., M.A., F.R.S. 
Edin. (Reporter). 

On the relative Strength and other mechanical Properties of Cast Iron ob- 
tained by Hot and Cold Blast, by Eaton Hodgkinson, Esq. 

On the Strength and other Properties of Iron obtained from the Hot and 
Cold Blast, by W. Fairbairn, Esq. 

1838. 

Account of a Level Line, measured from the Bristol Channel to tlie En- 
glish Channel, during the Year 1837-38, by Mr. Bunt, under the Direction 
of a Committee of the British Association. Drawn up by the Rev. W. 
Whewell, F.R.S., one of the Committee. 

A Memoir on the Magnetic Isoclinal and Isodynamic Lines in the British 
Islands, from Observations by Professors Humphrey Lloyd and John Phil- 
lips, Robert Were Fox, Esq., Captain James Clark Ross, R.N., and Major 
Edward Sabine, R.A., by Major Edward Sabine, R.A., F.R.S. 

First Report on the Determination of the Mean Numerical Values of Rail- 
way Constants, by Dionj-^sius Lardner, LL.D., F.R.S., &c. 

First Report upon Experiments, instituted at the request of the British 
Association, upon the Action of Sea and River Water, whether clear or foul, 
and at various temperatures, upon Cast and Wrought Iron, by Robert Mal- 
let, M.R.LA., Ass. Ins. C.E. 

Notice of Experiments in progress, at the desire of the British Association, 
on the Action of a Heat of 212° Fahr., when long continued, on Inorganic 
and Organic Substances, by Robert Mallet, M.R.I.A. 

Experiments on the ultimate Transverse Strength of Cast Iron made at 
Arigna Works, Co. Leitrim, Ireland, at Messrs. Bramah and Robinson's, 29th 
May, 1837. 

Provisional Reports, and Notices of Progress in Special Researches en- 
trusted to Committees and Individuals. 

1839. 

Report on the application of the sum assigned for Tide Calculations to 
Mr. Whewell, in a Letter from T. G. Bunt, Esq., Bristol. 

Notice of Determination of the Arc of Longitude between the Observato- 
ries of Armagh and Dublin, by the Rev. T. R. Robinson, D.D., &c. 

Report of some Galvanic Experiments to determine the existence or non- 
existence of Electrical Currents among Stratified Rocks, particularly those of 
the Mountain Limestone formation, constituting the Lead Measures of Alston 
Moor, by H. L. Pattinson, Esq. 



jcviii REPORT — 1841. 

Report respecting the two series of Hourly Meteorological Observations 
kept in Scotland at the expense of the British Association, by Sir David 
Brewster, K.H., LL.D,, F.R.SS. L. and E. 

Report on the subject of a series of Resolutions adopted by the British 
Association at their Meeting in August 1838, at Newcastle. 

Third Report on the Progress of the Hourly Meteorological Register at the 
Plymouth Dockyard, Devonport, by W. Snow Harris, Esq., F.R.S. 

1840. 

Report on Professor Whewell's Anemometer, now in operation at Ply- 
mouth, by W. Snow Harris, Esq., F.R.S., &c. 

Report on the Motions and Sounds of the Heart, by the London Com- 
mittee of the British Association for 1839-40. 

An Account of Researches in Electro-Chemistry, by Professor Schiinbein, 
of Basle. 

Second Report upon the Action of Air and Water, whether fresh or salt, 
clear or foul, and at various temperatures, upon Cast Iron, Wrought Iron, and 
Steel, by Robert Mallet, M.R.I.A., Ass. Ins. C.E. 

Report on the Observations recorded during the Years 1837, 1838, 1839, 
and 1840, by the Self-registering Anemometer erected at the Philosophical 
Institution, Birmingham. By A. FoUett Osier, Esq. 

Report respecting the two series of Hourly Meteorological Observations 
kept at Inverness and Kingussie, at the Expense of the British Association, 
from Nov. 1st, 1838, to Nov. 1st, 1839. By Sir David Brewster, K.H., 
F.R.S., &c. 

Report on the Fauna of Ireland : Div. Vertebrata. Drawn up, at the re- 
quest of the British Association, by William Thompson, Esq. (Vice-Pres. 
Nat. Hist. Society of Belfast), one of the Committee appointed for that pur- 
pose. 

Report of Experiments on the Physiology of the Lungs and Air-tubes. 
By Charies J. B. Williams, M.D., F.R.S. 

Report of the Committee appointed to try Experiments on the Preservation 
of Animal and Vegetable Substances. By the Rev. J. S. Henslow, F.L.S. 

1841. 

On the Tides of Leith, by the Rev. Professor Whewell, including a com- 
munication by D. Ross, Esq. 

On the Tides of Bristol, by the Rev. Professor Whewell, including a com- 
munication by T. G. Bunt, Esq. 

On Whewell's Anemometer, by W. S. Harris, Esq. 

On the Nomenclature of Stars, by Sir John Herschel. 

On the Registration of Earthquakes, by D. Milne, Esq. 

On Varieties of the Human Race, by T. Hodgkin, M.D. 

On Skeleton Maps for registering the geographical distribution of Animals 
or Plants, by — Brand, Esq. 

On the Vegetative Power of Seeds, by H. E. Strickland, Esq. 

On Acrid Poisons, by Dr. Roupell. 

Supplementary Report on Waves, by J. S. Russell, Esq. 

On the Forms of Ships, by J. S. Russell, Esq. 

On Railway Constants, by Dr. Lardner. 

On Railway Constants, by E. Woods, Esq. 

On the Constant Indicator, by the Rev. Professor Moseley. 



RESEARCHES IN SCIENCE. XIX 

The following Reports and Continuations of Reports have been undertaken to 
be drawn up at the request of the Association. 

On Salts, by Professor Graham, F.ll.S. 

On the Differential and Integral Calculus, by the Rev. Professor Peacock, 
M.A., F.R.S., &c. 

On the Geology of North America, by H. D. Rogers, F.G.S., Professor of 
Geology, Philadelphia. 

On Vision, by Professor C. Wheatstone, F.R.S. 

On Isomeric Bodies, by Professor Liebig. 

On Organic Chemistry, by Professor Liebig. 

On Inorganic Chemistry, by Professor Johnston, F.R.S. 

On the Salmonidse of Scotland, by Sir W. Jardine. 

On the Caprimulgidas, by J. Gould, F.L.S. 

On the state of Meteorology in the United States of North America, by 
A. Bache. 

On the state of Chemistry as bearing on Geology, by Professor Johnston. 

On Molluscous Animals and their Shells, by J. E. Gray, F.R.S. 

On Ornithology, by P. J. Selby, F.R.S.E. 

On the Specific Gravity of Steam, by a Committee, of which Mr. B. Don- 
kin is Secretary. 

On the recent progress and present condition of Electro-Chemistry and 
Electro- Magnetism, by Professor De la Rive, of Geneva. 

On the state of our knowledge of the Zoology of New Zealand, by Dr. 
Richardson and J. E. Gray, Esq. 

On the habits of the Radiata, by Sir C. J. Graham Dalzell, Bart. 

On the resistance of the Atmosphere to Moving Bodies, by E. Hodgkin- 
son, Esq. 

On the progress of Astronomy during the present century, by the Astro- 
nomer Royal. 

On the Theory of the Undulations of Fluid and Elastic Media, by Profes- 
sor Kelland. 



Recommendations for Reports and Special Researches, not involving 
Grants of Money, adopted by the General Committee at the Eleventh 
Meeting. 

Resolved — 
That the following Reports on the state of Science, formerly requested, be 
again asked for : — 

1. The Astronomer Royal: Second Report on the Progress of Astro- 

nomy during the present century. 

2. Professor Willis : Report on the State of our Knowledge of the 

Phaenomena of Sound. 

3. Professor Wheatstone : Report on Vision. 

4. Professor Kelland : Report on the History and Present State of the 

Theory of Undulations of Fluid and Elastic Media. 

5. Professor Bache : Report on the Meteorology of the United States. 

That Mr. Gould be requested to report on the habits of the Caprimulgidse, 
and that the Report be presented at the next meeting of the Association. 

That Sir William Jardine be requested to continue his researches on the 
Salmonidae, and that the Report be presented at a future meeting of the 
Association. 



XX REPORT — 1S41. 

That a Committee, consisting of Dr. Richardson and Mr. Gray, be re- 
quested to report on the present state of our Knowledge of the Zoology of 
New Zealand. 

The Report to be presented at the next meeting of the Association. 

That Sir J. Dalzell be requested to report on the Habits of the Radiata ; 
and that the Report be presented at the next meeting of the Association. 

That Mr. Gray be requested to report on the MoUusca and their Shells ; 
and that the Report be presented at the next meeting of the Association. 

That Mr. Hodgkinson be requested to complete his Experiments on the 
Resistance of the Atmosphere to Moving Bodies ; and to report the result 
to the next meeting of the Association. 



Recommendations of Researches in Science involving Grants of Money) 
. adopted by the General Committee at the Eleventh Meeting. 

That the Committee already appointed on Calculation of Tides at Bristol 
(viz. the Rev. W. Whewell) by Mr. Bunt, be re-appointed ; and that the sum 
of 20/. be placed at the disposal of the Committee for the purpose. 

The Report to be presented at the next meeting of the Association. 

That the Committee already appointed on the Reduction of the Stars in 
the Histoire Celeste (viz. Mr. Baily, the Astronomer Royal, and the Rev. Dr. 
Robinson) be re-appointed ; and that the sum of 651. be placed at the dis- 
posal of the Committee for the purpose. 

The Report to be presented at the next meeting of the Association. 

That the Committee already appointed on the extension of the Royal 
Astronomical Society's Catalogue (viz. Mr. Baily, the Astronomer Royal, and 
the Rev. Dr. Robinson) be re-appointed; and that the sum of 110/. (the 
residue of the former grant) be placed at the disposal of the Committee for 
the purpose. 

The Report to be presented at the next meeting of the Association. 

That the Committee already appointed on the Reduction of Lacaille's 
Stars (viz. Sir John Herschel, the Astronomer Royal, and Mr. Henderson) 
be re-appointed ; and that the sum of 105/. (being the unexpended balance of 
the former grant of 184/. 5s.) be placed at their disposal for the purpose. 

That Mr. Whewell, Lord Adare, Dr. Robinson, Sir J. Robison, Mr. Scott 
Russell, the Astronomer Royal, Mr. Snow Harris, Hon. and Rev. Charles 
Harris, be a Committee for obtaining information respecting the Velocity of 
Sea Waves, and for drawing up instructions for making the requisite observa- 
tions ; and that the sum of 30/. be placed at their disposal for the purpose. 

That Mr. Whewell, Colonel Sabine, Sir John Lubbock, the Astronomer 
Royal, and Mr. Snow Harris, be a Committee to procure observations of the 
Tides in the Pacific ; and that the sum of 60/. be placed at their disposal for 
that purpose. 

That a Committee, consisting of Professor Whewell, the Astronomer 
Royal, Professor Lloyd, Colonel Sabine, Professor Phillips, and Mr. Snow 
Harris, be appointed to make application to the Government for funds, for 
the publication of the series of Hourly Meteorological Observations whicli 
have been made for five years at Plymouth, at the expense of the Associa- 
tion, and to superintend the publication ; and that in case of the failure of 
this application, the sum of 250/. be placed at the disposal of the same 
Committee, for the purpose of carrying this object into effect. 



RESEARCHES IN SCIENCE. XXI 

That a Committee, consisting of the Rev. Dr. Robinson, Colonel Sabine, 
Professor Wheatstone, Rev. W. Whewell, the Astronomer Royal, Sir John 
Herschel, and Sir John Lubbock, be appointed ; for the purpose of conduct- 
ing experiments, by captive Balloons, on the Physical Constitution of the 
Atmosphere. 

The Report to be presented at the next meeting of the Association ; and 
that the sum of 250/. be placed at the disposal of the Committee for the 
purpose. 

That the grant of 60/., placed at the disposal of Sir D. Brewster, Mr. Osier, 
and Professor Forbes, for erecting an Anemometer at Inverness, be continued. 

That the sum of 40/. (including the remainder of the former grant) be 
placed at the disposal of Sir D. Brewster, for the purpose of continuing in- 
quiries into the Action of Media upon the Solar Spectrum. 

That the sum of 100/. be placed at the disposal of the Committee formerly 
appointed (consisting of Sir J. Herschel, Professor Whewell, Dr. Peacock, 
Professor Lloyd and Colonel Sabine), for conducting the co-operation of the 
Association in the system of simultaneous Magnetical and Meteorological 
Observations. 

That the sum of 65/., being the balance of a former grant, be placed at the 
disposal of Sir D. Brewster and Professor Forbes, for the purpose of revising 
and continuing the Hourly Observations at Inverness and Kingussie. 

That there be placed at the disposal of Mr. W. Snow Harris : — 

£ s. d. 
For some new Experiments on the Force and Velocity of the 

Wind 10 

For a continuation of the Observations, &c. with Whewell's 

Anemometer at Plymouth 800 

For defraying the expense of Observations, &c. with Osier's 

Anemometer at Plymouth 25 

For defraying the expense of the Hourly Observations of the 

Barometer, Thermometer, &c. at the Dockyard, Devon - 

port ; 40 



£83 

That the Committee formerly appointed to superintend the translation and 
publication of Foreign Scientific Memoirs be re-appointed (consisting of 
Colonel Sabine, Dr. R. Brown, Dr. Robinson, Sir J. Herschel, Professor 
Wheatstone, Sir D. Brewster, Professor Owen, Professor T. Graham, Professor 
Miller, Sir W. Jardine, Professor R. Graham) ; and that the sum of 88/. 18s. 
(being the residue of the grant of last year) be placed at the disposal of the 
Committee for the purpose. 

That the balance of the grant of 100/., for the reduction of Meteorological 
Observations (viz. 75/.), under the superintendence of Sir John Herschel, 
be continued. 

That the balance of the grant of 50/., viz. 32/. Os. 6d., for the revision of 
the Nomenclature of Stars, be continued to the Committee (consisting of Sir 
John Herschel, Professor Whewell, and Mr. Baily) formerly appointed for 
that purpose. 

That the Committee already appointed, viz. Dr. Prout, Dr. T. Thomson, 
Professor Owen, Professor Graham, and Dr. R. D. Thomson, be requested 
to undertake a series of researches on the Chemistry and Physiology of Di- 

1841. c 



Xxii REPORT — 1841. 

gestion ; and that tlie sum of 200/. be placed at their disposal for the pur- 
pose. 

The Report to be presented at the next meeting of the Association. 

That a Committee, consisting of Mr. R. Fox, Dr. Daubeny, and Mr. Ro- 
bert Hunt, be requested to continue a series of Experiments on the Action 
of various coloured Rays of Light on the Germination of Seeds and the 
Growth of Plants; and that the sum of 151. be placed at the disposal of the 
Committee for the purpose. 

The Report to be presented at the next meeting of the Association. 

That the Committee already appointed (consisting of Mr. Bryce, Mr. De 
la Beche, and Major Portlock), for Experiments on the quantity of Mud sus- 
pended in the Water of Rivers under different circumstances, be requested 
to continue their inquiries ; and that the sum of 201. be placed at their dis- 
posal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That the Committee already appointed (consisting of the President of the 
Royal Society, the Rev. Dr. BuckJand, R. I. Murchison, Esq., John Taylor, 
Esq., H. T. De la Beche, Esq., C. Vignoles, Esq., with power to add to their 
number), for taking measures to obtain Coloured Drawings of Railway Sec- 
tions before they are covered up, be requested to continue their labours ; and 
that the sum of 150/. be ])laced at their disposal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That Professor Johnston and Mr. Jeffreys be requested to repeat their ex- 
periments on the Solution of Silica in Water of a High Temperature;, and 
that the sum of 251. be placed at their disposal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That a Committee, consisting of Dr. Buckland, Mr. L. Horner, Mr. Wheat- 
stone, for England ; Lord Greenock, Mr. Milne, Professor Forbes, Mr. Pat- 
tison, for Scotland ; Capt. Portlock and Mr. Bryce for Ireland, be requested 
to register the Shocks of Earthquakes in England, Scotland, and Ireland ; and 
that the sum of 100/. be placed at their disposal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That Capt. Portlock be requested to continue his experiments on the Tem- 
perature of Mines in Ireland ; and that the sum of 10/. be placed at his dis- 
posal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That a Committee, consisting of the Marquis of Northampton, Dr. Buck- 
land, and Professor Sedgwick, be appointed for the purpose of advancing our 
knowledge of Belemnites ; and that the sum of 50/. be placed at the dis- 
posal of that Committee for the purpose. 

The Report to be presented at the next meeting of the Association. 

That for the purpose of promoting the publication of the drawings requi- 
site to the illustration of the Report on Fossil Reptiles, which was undertaken 
by Professor Owen, and is now completed, the sum of 250/. be placed at the 
disposal of a Committee, consisting of Mr. De la Beche, Mr. Hutton, Dr. 
Richardson, Mr. L. Horner, Col. Sabine, and Mr. Phillips. 

That Professor Owen be requested to draw up a Report on the British 
Fossil Mammalia; and that the sum of 200^. be placed at the disposal of Dr. 
Richardson, Dr. Buckland, and Mr. Richard Taylor, for the purpose of de- 
fraying the necessary expense of visiting and collecting materials, making 
drawings, &c. 

That the Committee already appointed (consisting of Dr. Prichard, Dr. 



RESEARCHES IN SCIENCE. XXIU 

Hodgkin, Mr. J. Yates, Mr. Gray, Mr. Darwin, Mr. R. Taylor, Dr. Wiseman, 
and Mr. Yarrell), for preparing a series of questions on the Races of Men, 
be requested to continue their labours ; and that the sum of 11. 10s. be placed 
at their disposal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That the Committee already appointed (consisting of Dr. Lankester, Dr. 
Arnott, Dr. Greville, and Dr. Fleming) to report on the Organic Beings of 
Mineral Waters, be requested to continue their researches, and that Dr. Dau- 
beny, Mr. Forbes, and Mr. Goodsir be added to the number ; and that the 
sum of 6/. be placed at their disposal for the pvirpose. 

That a Committee, consisting of Mr. Hugh Strickland, Dr. Daubeny, Pro- 
fessor Lindley, and Professor Henslow, be requested to continue the investi- 
gations on the Growth and Vitality of Seeds ; and that the sum of 10^., for- 
merly granted, be placed at their disposal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That a Committee, consisting of Mr. Babington and Mr. Garnons, be re- 
quested to continue the researches on the preservation of animal and vege- 
table substances ; and that the sum of 6^., formerly granted, be placed at 
their disposal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That a Committee, consisting of Mr. Gray, Mr. Forbes, Mr. Goodsir, Mr. 
Patterson, Mr. Thompson of Belfast, Mr. Ball of Dublin, Dr. Geo. Johnston, 
Mr. Smith of Jordan Hill, Mr. Couch, Mr. Bartlett, Mr. H. Bellamy, Mr. 
Walker, and Mr. Lyte, be requested to undertake a series of researches with 
the dredge, with a view to the investigation of the Marine Zoology of Great 
Britain, the illustration of the Geographical Distribution of Marine Animals, 
and the more accurate determination of the Fossils of the Pleiocene Period ; 
and that the sum of 50^., placed at the disposal of the Committee last year 
for the purpose, be continued. 

The Report to be presented at the next meeting of the Association. 

That the sum of 150/. be granted for inquiries into Vital Statistics. The 
Committee to consist of Lieut.-Col. Sykes, Viscount Sandon, Mr. G. R. Por- 
ter, Mr. J. Heywood, Dr. W. P. Alison, Dr. Cowan, Mr. E. Chadwick, and 
Mr. Watts. 

That the Committee already appointed on the Forms of Vessels (consisting 
of Sir J. Robison, Mr. Scott Russell, and Mr. J. Smith) be requested to com- 
plete their experiments on that subject ; and that the sum of 150/. be placed 
at the disposal of the Committee for the purpose. 

The Report to be presented at the next meeting of the Association. 

That a Committee, consisting of Professor Moseley, Mr. Enys, and Mr. 
Hodgkinson, be appointed for completing the dynamometrical experiments on 
the Steam Engine, and for applying the chronometrical apparatus of Poncelet 
and Morin, to determine the velocity of the piston at different periods of the 
stroke ; and that the sum of 100/. be placed at their disposal for the purpose. 

The Report to be presented at the next meeting of the Association. 

That a Committee, consisting of Professor Moseley, Mr. E. Hodgkinson, 
Mr. Brunei, and Mr. E.Woods, be requested to apply the Constant Indicator to 
Locomotive Engines on Railways ; and that the sum of 100/. be placed at 
the disposal of the above Committee for the purpose. 

The Report to be presented at the next meeting of the Association. 

c2 



Xxiv REPORT — 1841. 

Stjnopsis of Sums appropriated to Scientific Objects by the General 
Committee at the Plymouth Meeting. 

Section A. 

Hourly Meteorological Observations at Kingussie and Jnver- £ s. d. 

ness 65 

Tide Discussions : Leith 50 

Tide Discussions : Bristol 20 

Reduction of Meteorological Observations 75 

Nomenclature of Stars 32 6 

Stars in Histoire Celeste 65 

British Association Catalogue of Stars 11000 

Erection of Anemometer at Inverness 60 

Action of Gases on Light 40 

Lacaille's Stars 105 

Meteorological Observations at Plymouth 40 

Whewell's Anemometer at Plymouth 800 

Magnetic Co-operation 100 

Scientific Memoirs 88 18 

Velocity of Sea Waves 30 

Tides in Pacific 60 

Publication of Meteorological Observations 250 

Experiments with Balloons 250 

Force and Velocity of Wind 10 

Osier's Anemometer at Plymouth 25 

£1433 18 6 
Section B. 

Chemistry and Physiology of Digestion 200 

Action of Light on Growth of Seeds 1500 

£215 
Section C. 

Mud in Rivers 20 

Railway Sections 150 

Subterranean Temperature in Ireland 1000 

Earthquake Registration 100 

Solution of Silica in Water at High Temperatures 25 

British Belemnites 50 

Fossil Reptiles (Publication of Report) 250 

£605 
Section D. 

Preservation of Animal and Vegetable Substances 6 

Marine Zoology 50 

Plants and Animals in Mineral Waters 6 

Vegetative power of Seeds 10 

Races of Men 7 11 

British Fossil Mammalia 200 

£279 11 
Section F. 

Vital Statistics 150 



SYNOPSIS. XXV 

Section G. £ *. d. 

Dynamometric Instruments 100 

Forms of Vessels 150 

Constant Indicator to Locomotives 100 



£350 
Total of Money Grants .... £3033 9 6 



Extracts from Resolutions of the General Committee. 

Committees and individuals, to whom grants of money for scientific pur- 
poses have been entrusted, are required to present to each following meeting 
of the Association a Report of the progress which has been made ; with a 
statement of the sums which have been expended, and the balance which re- 
mains disposable on each grant. 

Grants of pecuniary aid for scientific purposes from the funds of the Asso- 
ciation expire at the ensuing meeting, unless it shall appear by a Report that 
the Recommendations have been acted on, or a continuation of them be 
ordered by the General Committee. 

In each Committee, the Member first named is the person entitled to call 
on the Treasurer, John Taylor, Esq., 2 Duke Street, Adelphi, London, for 
such portion of the sum granted as may from time to time be required. 

In grants of money to Committees, the Association does not contemplate 
the payment of personal expenses to the Members. 

In all cases where additional grants of money are made for the continua- 
tion of Researches at the cost of the Association, the sum named shall be 
deemed to include the specified balance which may remain unpaid on the 
former grant for the same object. 



On Thursday evening, July 29th, at 8 p.m., the President, the Rev. W. 
"Whewell, M.A., F.R.S., Professor of Moral Philosophy in the University of 
Cambridge, took the Chair in the Town Hall, Devonport, and read an Ad- 
dress (see next page). 

On Friday evening, July 30th, in the same room, Mr. Chatfield, of H. M. 
Dock Yard, Devonport, gave an account of the construction and launch- 
ing of ships, with reierence to the launch of the Hindostan (80 guns) on 
Monday evening. 

On Tuesday evening, August 3rd, Mr. Dent explained a new Clock ; Dr. 
Reid illustrated his processes of Ventilation ; Mr. De Moleyns exhibited a 
Voltaic Battery ; and Mr. Brunei described the Thames Tunnel. 

On Wednesday, at 8 p.m., the Concluding General Meeting of the 
Association took place in the Town Hall, Devonport, when an account of the 
Proceedings of the General Committee Avas read bv Colonel Sabine. 



ADDRESS 



BY 



THE REV. PROFESSOR WHEWELL, F.R.S., &c. 



Gentlemen, — It now becomes my business to take upon myself the office 
of President of the British Association, in virtue of my election to that 
situation, which took place at the meeting at Glasgow last year in the usual 
form. The election was made in my absence, and contrary to ray expecta- 
tion ; but of my own views and feelings with regard to the widdoni of the 
choice then made, I shall not say one word. I will only remark, that any 
apprehension which I may entertain of my own unfitness for this office, and 
of the superior claims of others to the distinction, will have no other effect 
than that of making me more diligent and scrupulous in the discharge of my 
official duties, since those are the merits which are most within my reach, 
and for the want of which no eminence, either in science or in society, can 
compensate. It cannot but occur to those who are acquainted with the pro- 
ceedings of the Association in past years, that it would be agreeable to the 
general course of its usage, if this Chair were occupied by some illustrious 
man of science belonging to this region of England ; (the region does not 
want for such as by their powers and their European reputation might fitly 
be placed at the head of any scientific association in the world) or again, if 
it were occupied by some of those men of eminent rank and influence in the 
district and in the empire, who have shown, by their attendance here and by 
their services rendered to this meeting, their approbation of the objects of 
the British Association, and their good will towards its members. But if 
you had met under a President whose claims to your attention, however 
high, were of a merely local nature, while at the same time no one of the 
primary officers of the last meeting, the President and Vice-Presidents, were 
present, to transmit into his hands, by a visible act, the dignity of which I 
have the honour now to be the temporary holder, it might seem as if the 
continuity of the Association had been interrupted, — as if this were rather a 
new institution, arising in this district, than a new meeting of a body which 
has had, now for eleven years, a connected and unbroken existence. My 
hand may serve at least to transmit the torch from one place of assemblage 
to another, — to bring the sacred fire which has been lit and kept alive at the 
former meetings of our body, and to place it upon the altar which has been 
erected in this great maritime town. On one account, at least, I may ven- 
ture to undertake such a ministry as this : I have been a faithful attendant 
upon the meetings of the Association ever since its first institution, and there 
is scarcely any subordinate oflSce of labour or dignity in the constitution of 
the body which I have not at one place or other discharged, with such zeal 
and care as was in my power. However the Council may have judged well 
or ill in this selection, they have at least this excuse, that they have not gone 
out of their way to make it, — that they have not placed in this liigh office of 
the Association one whose willingness to serve it, and to be for the time 
identified with it, was at all doubtful, so far as past events could prove it. 



xxviii REPORT — 1841. 

In proceeding to the business of the Association, it is not uiy intention to 
attempt to give you any account of tlie arrangements and prospects of the pre- 
sent meeting, nor of the proceedings of the last, and tlie transactions of the 
intermediate time. In several preceding years, there has been laid before the 
first General Meeting of the Association a statement of the main contribu- 
tions to science, which were included in the recent Proceedings of the body, 
— a survey and estimate of the scientific work done during the twelvemonth. 
This is a task always difficult, and sometimes long ; and I believe many of 
you, who know the character which it almost necessarily assumes, of a col- 
lection of abridgments of papers on abstruse points of science, will not regret 
its being occasionally omitted. But perhaps I may be allowed to occupy you 
for a few minutes with a slight sketch of the general aspect which the Asso- 
ciation now appears to me to offer to a thoughtful spectator ; — of the place 
it holds among the characteristics, and I may say, the institutions of our time 
and country. Such a view of our position may serve to remind us of our 
duties to the Association, and to the gi'eat cause Avhich it represents, and may 
guide and animate us in the discharge of them. 

Those of you who are acquainted with the writings of the greatest of 
our philosophers, are aware that several of them, contemplating the past 
progress and future prospects of science in that spirit of comprehensive 
thought and large hope, which the subject so strongly calls for, have imagined 
some vast Institution, by which the advance of science should be systemati- 
cally and powerfully aided ; — some great Philosophical College, which should 
have for its business, not to teach mainly, but to make discoveries — to extend 
our knowledge of every part of nature by all the appliances which experi- 
ment and theory, observation and calculation, ingenuity and perseverance, 
can supply ; and in addition to these, by more material resources, money and 
a multitude of fellow-labourers. You recollect, perhaps, the great Bacon's 
remarkable picture of the New Atlantis. The imaginary teacher, whom he 
introduces as one of the sages of this Utopian region, describes to the in- 
quiring traveller an institution which he calls Solomons House, and which is 
such a college for making discoveries as we- have just spoken of. Of this 
institution, he says, " The end of our foundation is the knowledge of causes 
and secret motions of things, and the enlarging the bounds of the human 
empire to effecting of things possible." As parts of this house, there are 
described caves and wells, chambers and towers, baths and gardens, parks 
and pools, dispensatories and furnaces, and many other provisions for experi- 
ment and observation. There are also many classes of persons who conduct 
the business of this college, and whom, according to their employments, he 
calls by somewhat fanciful names — merchants of light ; mystery men ; depre- 
dators ; pioneers, or miners ; compilers ; doivry men, or benefactors ; lamps ; 
inoculators ; and finally, interpreters of nature, who elevate the truths of ex- 
periment into general laws, the highest forms of human knowledge. 

Other philosophical writers have presented, in various ways, somewhat of 
the same conceptions. But, you will perhaps say, all this is mere imagination. 
Such an institution exists only in Utopia : it Avas never contemplated as a 
reality. True : it is ideal, just as all the highest forms of human institutions 
are ideal. It is Utopian, just as a perfect monarchy, perfectly administered, 
is Utopian. But if Ave conceive a perfect monarchy, where the sovereign 
has unlimited power, which he exercises with entire wisdom and justice, while 
the resources of the state are ample, and the character of the nation is intel- 
lectual and progressive, must we not, in such an Utopia, include also the 
notion of such a college of discovery ? Beyond all doubt, if we imagine to 
ourselves a New Atlantis, we must also place in it a Solomon's House. Still, 



ADDRESS. XXIX 

you will say, all is imaginary — and to what use do we feed our minds with 
these empty pictures of unattainable good? To what use, do you ask? 
Some of you, well aware that, in the constitution of man, imagination and 
hope, — the boldest imagination, the loftiest hope, — are not without their use 
— aware what that use is, have already answered this question in your own 
hearts. Of what use are the ideal pictures of objects that tend to elevate 
and improve the condition of man ? Of that use, which, if we disregard, the 
condition of man forthwith becomes degraded, and his prospects a blank. 
They are of use in raising our thoughts and stimulating our exertions, so 
that we may become Aviser, and better, and nobler than we are. Is this a 
new doctrine ? God be thanked, in this country at least, it has long been 
familiar to men's minds — has been practically acted upon, and has been 
attended with the most blessed and glorious effects. Let us look to other 
objects, very different from the increase of knowledge, and we shall easily 
discern the operation of this doctrine. It is not difficult to see in what form 
we may expect to find it showing itself. For if we imagine this Utopia of a 
perfect government, Solomon's House will not be the only ideal institution 
there. In such a land of justice, and wisdom, and religion, we shall have 
colleges for diffusing justice, and wisdom, and religion over the face of the 
earth. We shall have a college for teaching the poor, a college for repress- 
ing the vicious, a college for the abolition of slavery, a college for diffusing 
Christianity over the face of the globe. Such colleges we should have in our 
Utopia — but Utopia is not. What then ? do we therefore despair of these 
great objects ? Do we sigh to think that all this contemplated good is mere 
imagination ? Do we lament that we are not in an absolute monarchy, 
where the wisdom of the sovereign, supported by unlimited power, might 
call into existence those beneficial institutions ? Do we despair of these 
great and good objects, because we live in a state of society where men act 
each for himself, unforced by supreme power ? Do we cast away our ideas, 
because we are not likely to be carried towards their realization by the whole 
power of the state ? Do we do this ; or do we not do something very dif- 
ferent ? Something very different indeed we do. We still keep our thoughts 
fastened upon our ideas of what is highest and best ; but feeling that we are 
free, and that it is our glorious privilege to act as freemen, we attempt to 
realize our ideas, not by the power of the state, but by that power which, in 
such a state and on such subjects, represents the conviction of the nation, the 
power of voluntary association. We have had thus, — not state colleges, but 
voluntary societies, — for Christianizing the Heathen, for teaching the igno- 
rant, for repressing the vicious ; and we had a voluntary Society for the Abo- 
lition of Slavery, till the principle of voluntary association, in that instance, 
thank God I performed its work even to the end, by inducing the State to take 
up and carry into effect the great object which had been the aim of the vo- 
luntary society from its foundation. 

What, then, is the conclusion to which we are led, by looking at the spirit 
of our country, as shown in its most strenuous exertions and most glorious 
acts, and combining this view with the loftiest ideal aspirations of the greatest 
philosophers the land and the world have produced ? What but this ? that 
with regard to that institution, which has for its object to extend the bounds 
of human knowledge, we must realize the idea in the same manner as we 
endeavour to realize other ideas in our practice ; — that what in a perfect 
monarchy would be done by a wise sovereign, we must do by voluntary 
exertion ; — that in the place of a Solomon's House supported by the State, we 
must have a British Association supported by ourselves. 

The British Association has now for ten years discharged the office of such 



XXX REPORT — 1841. 

an institution as we have spoken of. Considerable funds, raised by the con- 
tributions of its members, and expended under its direction, have been em- 
ployed in furthering and verifying discoveries. It is true that we have not 
attempted to erect such edifices, and to make such preparations for the pui'- 
poses of experiment, as Bacon introduces into his picture ; but we have at- 
tained the same end more effectually, by procuring the use of many of the 
great establishments of manufacture and commerce which this empire pos- 
sesses. We have had experiments carried on at furnaces and iron-works, on 
railroads and canals, in mines and harbours, with steam-engines and steam 
vessels, upon a scale which no institution, however great, could hope to reach ; 
but which has been placed in our power by the enlightened liberality and 
scientific zeal of the proprietors and directors of such means of research. 
We have not had various bodies of professors of the art of discovery em- 
ployed in these inquiries — we have not attempted to form classes of mystery 
men and dowry men — collectors of facts and interpreters of nature ; — but we 
have found the most gifted and eminent cultivators of science in our own 
country, and several of those of other countries, ready and willing to under- 
take for us the office of exploring and interpreting nature — of extending and 
applying art. No institution, however formed, could have hoped to collect, 
as its active members, such a body of philosophers as have gladly come for- 
ward to labour for us, and have freely given us the resources of their vast 
powers and matured skill. Mathematicians, and astronomers, and geologists, 
and chemists, and naturalists, illustrious through Europe, have superintended 
the execution of our commissions with as much care as their own most favor- 
ite researches ; and we have seen a co-operation of experimenters and cal- 
culators, observers and generalizers, such as might satisfy the wishes of Ba- 
con himself. 

That 1 may not dwell on mere generalities, I will mention a few of the 
sums expended by the Association upon scientific researches ; which, when 
it is understood that they have been spent under the direction and vigilant 
control of such men as 1 have spoken of, will show the amount of service 
which has been rendered to science by that body. In the first three years, 
the sums thus expended were small, the Association having been mainly em- 
ployed in collecting information which might direct its future proceedings. 
In the fourth year 167/. was thus spent, and from this time the sum went on 
rapidly increasing. In the fifth year it was nearly 500/. ; in the sixth and 
seventh nearly 1000/. each year; in the eighth and ninth above 1500/. each 
year ; and it appears that during the past year we have expended in this 
manner the sum of 1 240/. And these sums, it is to be observed, are only a 
part of what were voted ; at Liverpool, in 1 837, above 3000/. was voted, of 
which 1000/. only was applied for; at Newcastle 3700/. was voted, and 
1600/. of this only paid: at Birmingham 2800/. was voted, and 1500/. paid ; 
the sum voted at Glasgow last year was 2600/., of which, as I have said, 
your Treasurer has really paid 1240/. 

These differences of the sums voted and paid in each year are evidence of 
the care with which the resources of the Association are husbanded ; for the 
sums voted were to be had on application made by the persons to whom 
their disposal was intrusted ; but they were not applied for, except in pro- 
portion to the scientific work which was done ; and those who undertook 
these labours for us carefully confined their expenditure within the narrowest 
possible limits. It would occupy you too long if I were to mention in detail 
the subjects to which these sums have been applied ; but I may state in gene- 
ral, that above 900/. has been expended by us in the furtherance of astro- 
nomy, mainly upon the object of reducing observations already made, into 



ADDRESS. XXXI 

such a form that they can be directly compared with the theory. Above 
800/. has been expended on tide observations ; 250/. on experiments on waves ; 
500/. on experiments on the best form of vessels ; 200/. on experiments on 
cast iron ; about 400/. has been employed in various labours relative to me- 
teorology ; and above 300/. on the description of fossil fishes and reptiles. I 
shall not detain you by mentioning smaller sums which have been devoted to 
various objects ; but I may call to your notice a work executed mainly in 
this county, upon which the Association expended about 550/ in 1838 and 
1839. This work consisted in striking a level line from the north coast of 
Somersetshire to Axmouth, in order to determine whether the level of the 
sea is the same in the Bristol Channel and in the British Channel, and in 
order to afford a standard of reference in future times, if, from any cause, the 
relative level of the land and the sea should change. This operation has 
already afforded us the means of determining, that the great land slip, which 
has recently taken place near Axmouth, was not accompanied by any per- 
manent change in the level of the land itself, where a block of granite lies, 
which marks one of the extremities of our level line. 

Since the first institution of the Association, about 7000/. has been ex- 
pended on such objects as I have pointed out : but it is impossible for any 
one, who knows the nature of scientific researches, and the difference between 
the result of money expended in experiments by a good and a bad philoso- 
pher, to doubt that this sum has produced effects which many times the sum 
applied without the same advantages could not have obtained. Without the 
encouragement of the Association, these researches would never have been 
undertaken ; without the aid of such men as have frequented the meetings 
of the Association, they would have been attempted to no purpose. It has 
been said of certain parts of Europe that they afford— 

Iron and man, the soldier and his sword ; 

in like manner we may say of this Association, that it has supplied at the 
same time the philosophical soldier and the weapons with which he gains his 
victories over nature. 

But further, besides the expenditure of its own funds, the Association has 
been the means of procuring the appropriation of very large sums to scientific 
purposes from the national resources. At the suggestion or request of this 
body, the reduction of the observations of the planets made at Greenwich 
from the time of Bradley has been completed ; and the reduction of the ob- 
servations of the moon has been begun. Up to the present time, about 
2200/. has been expended in all. And by a letter from the Astronomer 
Royal, received since I came here, I am informed that, within a few weeks, 
the Government expressed great willingness to advance more money for this 
purpose ; and Mr. Airy adds, that next Monday he is to have twelve calcu- 
lators employed upon the work. We have applied to the Government for 
the extension of the Ordnance Survey into Scotland, and have received a 
favourable answer. We have tendered our advice that the Ordnance Survey 
of England shall in future be conducted on a larger scale in the mining and 
metalliferous districts, and this advice is already acted on in the northern 
counties of England, where the survey is now proceeding on a scale of six 
inches to a mile. 

Above all, I must mention an undertaking, entered upon in pursuance of 
our repeated recommendations (a service which the philosophers of future 
ages will duly estimate), — the great Magnetical Survey of the terrestrial 
globe, by the combined operation of a naval expedition and fixed observa- 
tories in every quarter of the world, which is now carrying into effect ; — a 



XXxii REPORT — 1841. 

scientific work, this — far surpassing, in the scale of its means and in the com- 
pleteness of its design, any ever yet attempted, and such as Bacon might 
have assigned to the sages of his New Atlantis, if he had, in imagination, 
extended their polity from the Atlantic to the Pacific, and from Pole to Pole. 

We most gladly bear our testimony to the liberality and spirit with which 
Her Majesty's Government have accepted and acted upon our suggestions ; 
nor is this testimony at all weakened by our claiming for distinguished mem- 
bers of our own the merit of having brought into view the importance of 
such an undertaking, laid before the English public the progress which the 
subject was making in other countries, planned the scheme of operations 
which our own exertions ought to follow, and animated the observers, by 
giving them the certainty that their observations will be well used and fully 
appreciated. 

When we can point to these numerous and valuable direct results of our 
exertions, we cannot at all waver in our conviction, that those persons acted 
in the truest spirit of the age, and of the nation, who, eleven years ago, 
framed the design of a voluntary association for the advancement of science 
among the subjects of this empire ; and that the liopes and expectations 
which such an institution might naturally exercise, have been fully verified by 
the course and progress, the labours and successes of the British Association. 

I do not doubt that the present Meeting will continue to uphold the cha- 
racter of the Association, and will be inferior to none of the preceding in 
the value and interest of its proceedings. We are not yet likely to want for 
matter to labour upon. The collection of facts and the reduction of them by 
various calculations is still required to a vast extent, in order that our know- 
ledge may make the next step of progress to which its path invites our hopes. 

It is easy to point out vast fields of research, on which our resources and 
our energies may be applied with every prospect of a rapid increase of know- 
ledge. For, in fact, how little has been done for science, by the collection 
of exact and long-continued series of observations, such as he must have 
before him who is to interpret nature I In astronomy, indeed, this has been 
done : sovereigns, and nations, and opulent individuals have thought their 
wealth well bestowed in providing costly instruments, and rewarding the 
astronomer through his daily and nightly toils. The stars have been well 
observed from the beginning of civilization ; but, for the purposes of science, 
we ought to have observations as careful and as continued of all the other 
parts of nature as we have of the stars. The tides, the waves, the winds, and 
all the other changes of the air, pressure, temperature, moisture, magnetism, 
electricity, chemical changes, and even those of vegetable and animal life, — 
all these afford materials for researches full of importance and interest. For 
these, the time is, perhaps, not yet come, when they can be urged upon 
governments as a part of their business, in the same way in which astronomy 
is; — except, perhaps, magnetism, which has already taken its place in our 
observatories by the side of astronomy, in our own and other countries. 
Those other subjects, then, are fitly cultivated by a voluntary association 
such as ours; and the occasions of fitly doing this will doubtless be sug- 
gested to us from time to time by our members. On the present occasion, a 
distinguished Belgian philosopher, one of our corresponding members (M. 
Quetelet), comes to us to invite us to take a part in determining, by extensive 
observations, the changes which atmospheric conditions produce in periodical 
phfenomena, — such as the times of the leafing and flowering of plants, of the 
arrival of birds, and the like. He has obtained extensive co-operation in his 
own country, and no doubt will find fellow-labourers in ours. Meteorology, 
in its largest sense, is a subject which, although great collections of observa- 



& 



ABDRESS. XXXUl 

tions have been made, is hardly yet a science : yet the interpreters of this 
part of the book ot nature have already begun to spell out some phrases, 
which show that the language is not wholly unintelligible ; and here, there- 
fore, we may go on hopefully, recollecting always that the collection of facts 
is a matter of comparatively small value, except we can also trace in them 
some rule or order. The mere gathering of raw facts may be compared to 
the gathering of the cotton from the tree. The separate filaments must be 
drawn into a connected thread, and the threads woven into an ample web, 
before it can form the drapery of science. 

We ought to have meteorological observations and observers distributed 
over the face of the globe : and even this would not be enough ; for we wish 
to know not only what passes on the earth's surface, but through the whole 
depth of the atmosphere ; hence it would be desirable to have observations 
made at elevated points free from the action of the ground — such as can only 
be attained by the aid of balloons. Such an undertaking has been under the 
consideration of a committee during the past year, and a report on the sub- 
ject has come before the Physical Section. 1 trust that on this subject you 
will soon hear more. As other subjects on which we still want facts — that 
is, numerous and systematical collections of facts, and laws deduced from 
facts — I may mention the tides of the Pacific, the velocity of sea waves, and 
subterraneous temperature. Another class of inquiries well fitted for our 
labours, is the determination of the fundamental elements, or constants, of 
operations of engineering, as the constants of railroads, steam-engines, and 
other works of art, which form part of the wealth and resources of this great 
empire. These are already under investigation. The addition of a Section 
of Practical Mechanics and Engineering to the previous constitution of the 
Association, which took place at Bristol, showed the interest which such in- 
quiries inspire ; and various committees have collected much valuable informa- 
tion of this kind, and will, we trust, collect much more. 

There is also another Section of the Association, added to its plan at Cam- 
bridge, which has for its object researches of a highly interesting kind, — I 
mean the Section of Statistics ; and we trust that there is ample employment 
for this Section, in subjects which can be dealt with in the same calm specu- 
lative spirit as the other sciences which we here cultivate. 

It may, perhaps, sometimes be useful to us to recollect that in many 
statistical subjects, the discussion, and even the collection of facts, is rather 
the office of a legislative than of a scientific body. The wise institutions of 
Bacon's New Atlantis would have assigned to the governors of the land, and 
not to the sages of Solomon's House, the collection of information respecting 
the habits, numbers, and education of the people, where the information is 
such as almost necessarily suggests legislation, or discussions having legisla- 
tion for their natural end, and involving the deepest political and moral con- 
siderations. There may very fitly be voluntary associations, which aim 
directly at improving the intellectual, or moral, or social condition of our 
population ; but we must ever remember that we are an association for a dif- 
ferent purpose, namely, the advancement of science ; and we are bound alike 
by our regard to the prosperity of our body, and by our most solemn and 
repeated declarations, to avoid the storm of opinions which is always raised 
when the parties which aim at social permanence and social progress are 
brought into conflict. The pursuit of scientific truth is, no doubt, a means 
of indirectly elevating man's intellectual and social condition ; but we 
assemble in order to promote the direct pursuit of scientific truth ; and we 
must not turn aside into the more wide and tangled paths of those who make 
its collateral effects their main object. Knowledge is power, we are told. 



XXxiv REPORT — 1841. 

Knowledge is power ; but for us, it is to be dealt with as the power of inter- 
preting nature and using her forces ; not as the power of exciting the feel- 
ings of mankind, and providing remedies for social evils, on matters where 
the wisest men have doubted and differed. 

Being the person whose voice is first raised in addressing the meeting of 
the Association, I have thought that it was a part of my duty to use the 
opportunity in calling to our minds the fundamental character and principles 
of our institution. There are other subjects which our constitution directs 
us to avoid ; but none perhaps in Avhich there is much danger or need of 
warning. We are in no great risk of deviating into literary, or metaphysical, 
or theological discussions. Sound metaphysics and literary culture will of 
course show themselves in the addresses of those who possess such accom- 
plishments, but are no direct objects of our attention. And in like manner, 
though we cannot dream of the slightest approach to the discussion of 
religious questions, heartfelt and real piety may be apparent even in the 
sentiments uttered at an association for the advancement of science. I am 
sure that many of you who attended the former meetings of this Association, 
must recollect occasions on which men's minds being excited, and yet solem- 
nized, by the aspect of the assembled multitudes, and by the lofty views of 
nature which our philosophers had to present to them, the thoughtful and 
eloquent men who had to address you were carried by a spontaneous impulse, 
without plan or premeditation, into elevated strains of religious reflection ; 
showing that those who take the lead in our meetings have their minds so 
tuned, that every voice which proclaims the wonders of nature, turns their 
thoughts to the Author of nature ; that every new gleam of truth seems to 
them an effluence from the eternal fountain of truth. Long may such habits 
of thought prevail among the philosophers of this land ; and then we need 
not fear but that knowledge, hallowed and elevated by the spirit in which it 
is pursued, will be every way a blessing to man, — to his soul as well as to his 
body — to his spiritual as well as to his intellectual being. 

To those of us who, knowing the institution by our attendance upon it, 
and our share in its labours, think thus of its value and its spirit, every new 
annual occasion of our coming together must be an occasion of fresh grati- 
fication, an agreeable exercise of memory and of hope. In our present 
meeting at this place, there are many circumstances to give additional ani- 
mation to our anticipations of pleasure. We come to a part of the empire 
hitherto unvisited by many of us, to a great maritime town, replete with 
objects of instruction, art, and interest. We know the love of science and 
the familiarity with its treasures which here prevail, for we are acquainted 
with the high character, the knowledge, zeal, and ability of the authorities of 
the Dockyard — the intelligence and activity of the Plymouth Institution, — 
we know and feel most gratefully, the kind and vigilant care with which pre- 
parations have been made for our reception ; and we now see in this assem- 
bly, the look of cordial welcome and lively anticipation, of which I would 
say more, but that I would beg to leave the subject in abler hands. We hail 
with joy and confidence the opening of the Plymouth Meeting of the British 
Association. 

Perhaps you will allow me the gratification of saying a word respecting 
special personal reasons of my own, which make it a matter of pleasure to 
me to find myself here on this occasion. Besides that it brings me to the 
society of several valued and cherished friends, whose home is in this part of 
England, I have various ties of a scientific nature with this place and this 
region. The excellent observations of the tides made in this harbour, have 
been the subject of calculations involving considerable labours, which I have 



ADDRESS. XXXV 

made or directed : and some curious traits in the laws of tidal phgenomena 
here, which were noticed as early as the time of Newton, have, I trust, been 
followed out to a tolerably exact determination. An anemometer, which I 
had devised, has been erected here, with most valuable improvements, by 
Mr. Snow Harris, and has been for some time in operation. And when I 
consider, as we may do, this meeting as a meeting peculiarly intended to bring 
the Association in contact with the West of England, I find that Cornwall 
returns to my thoughts, with all the scientific zeal and intelligence, which 
from my own personal intercourse I know to exist among the miners of that 
county. Perhaps I have had very unusual opportunities of becoming ac- 
quainted with their merits, for in two different years (1826 and 1828), in the 
prosecution of certain subterraneous experiments, undertaken in conjunction 
with the present Astronomer Royal and other persons, I lived four months 
the life of a labouring miner, and learnt how admirable for skill and conduct 
is the character of all cleisses of the mining population in that region. If any 
of my Cornish friends are within hearing, I gladly bid them God speed, and 
claim once more their welcome to the West. And that I may no longer 
detain you, to all of you, gentlemen of the British Association, I bid God 
speed ; and from all of you, gentlemen of Plymouth and its neighbourhood, 
I seem to hear, Welcome to Plymouth ! 



REPORTS 



ON 



THE STATE OF SCIENCE. 



On the Present State of our Theoretical and Experimental Knowledge 
of the Laws of Conduction of Heat. By the Rev. Piiii^ip Kell and, 
M.A., F.R.SS. Lond. and Edin., Prof of Math, in the University 
of Edinburgh, late Fellow of Queen's College, Cambridge. 

1 HE object of the following report is simply to lay before the Association an 
outline of the present state of our theoretical knowledge of the law of trans- 
mission of heat by conduction, and to examine how far conclusions deduced 
from theory have been tested by experiment. Reports on the general pro- 
blem of Radiant Heat have already appeared by Professor Powell * ; and on 
the theoretical laws of conduction and radiation, a portion of the subject- 
matter of our present question, Mr. Whewell has briefly touched in his report 
< On Magnetism, Electricity, Heat, &c.t' We shall, in consequence, confine 
ourselves strictly to our immediate limits, noticing only such other branches 
of the general theory as bear directly or necessarily on the question. We 
shall avoid all mention of theoretical investigations, however important in 
themselves, which are not capable of being examined rigidly by direct expe- 
riment ; nor shall we scruple to pass over the names of a host of illustrious 
experimenters on conduction and radiation, when we find that their experi- 
ments are not calculated to serve as the immediate test of theory. This pro- 
ceeding will materially shorten our labour, and will have the effect of con- 
densing into a narrow compass all the remarks we have to make. 

To render wiiat has to be said as clear as possible, the subject-matter has 
been arranged under three heads. Two of these are distinctly marked out 
by the statement of the object proposed to be effected, and the third is sug- 
gested by a consideration of the former two. 

We shall examine, then, I. What is the present state of our theoretical 
knowledge of the phsenomena of conduction. W^e are here to seek for the 
principles on which the reasoning is based, to inquire what are the axioms of 
radiation and conduction, or of the flow of heat, which, from observation, 
experiment or analogy, have been assumed to hold true, and to point out the 
conclusions to which these axioms have led. We have to distinguish between 
differing theories, and to contrast with each other some of the most simple of 
the results to which they respectively lead. This portion of our subject must, 
to a certain extent, be treated historically. 

We shall inquire, H. into the state of experimental investigation, so far as 
it has been undertaken with a view to test or to illustrate the conclusions 
arrived at by theory. We shall examine how the different consequences of 
certain hypotheses bear the test thus applied to them, by computing from the 

* Report on Radiant Heat in Reports of British Association, vols. i. and ix. 
t Reports of the British Association, vol. iv. 
1841. B 



2 REPORT — 1841. 

fonnulse the values of the temperature corresponding with the conditions 
existing in the experiment, and contrasting the results with the temperatures 
actually observed. This critical discussion of the hypotheses will lead us in 
the third place 

To point out, III. the utter inadequacy of the few experimental facts with 
which we are furnished, to serve either as the basis of a true theory or as the 
indication of a false one. We admit that, of a theory based on assump- 
tions which have been for a century regarded as only approximative to trul h, 
the experiments are sufficient to expose the incompetency, just as experi- 
ments on bodies sliding under the retardation of friction will easily detect thje 
inadequacy of formulae deduced from the hypothesis of absolute smooth- 
ness. But we shall see that, as applicable to point out errors in the assumed 
axioms on which reasonings are founded to constitute a physical theory, the 
experiments we possess are defective both in their number and in their na^ 
ture. We shall find three distinct theories equally verified or equally over- 
turned by them, according as we choose to regard the conclusions as indi- 
cating the one or the other ; and yet we are quite sure that only one of the 
theories is the correct one, whilst on the other hand we can hardly entertain 
a doubt that one of them is so. When we shall have made this appear, it 
will only remain for us to point out, in conclusion, what are the most im- 
portant results of theory which it is desirable that experiment should be 
brought in to test, and to suggest a few of the most simple means of effecting 
the object desired. 

I. The problem, in the solution of which consists the mathematical theory 
of heat, is the following. Having given the state of heatijig, or the variation 
of that state from time to time, at one or more points of a homogeneous body 
of given form and dimensions, to find the permanent or variable temperature 
at every other point. Thus a ring is kept at a certain temperature at one 
point, and it is proposed to discover, 1. what is the variation from time to 
time of the temperature at every other point, and 2. what is the ultimate 
temperature to which that at any given point ai^proaches as the time during 
which the constant heating of one point has been kept up is increased. 

From this statement it will appear that the experimental facts on which the 
theory must rest are the answers to the following questions, a. According 
to what law does a heated body lose its temperature to the air, or other me- 
dium or space, by which it is surrounded ? h. According to what law is 
temperature transmitted fi'om point to point of a body ? On the correctness 
of the answers which may be assumed as given to these questions depends 
the applicability of the results obtained to the state of things in nature. But 
as in mechanics we may reason correctly on assumed laws which are not laws 
of nature, and obtain conclusions of great importance as approximations to 
facts, so in the theory of heat the results, although strictly commensurate only 
with the laws on which they depend, are still highly important even in refer- 
ence to the things actually existing, differing as they do in certain cases from 
the expression of the laws. 

We proceed then to show what answers have been given to the above 
questions by different theorists, and to explain the evidence on which their 
truth is supposed to be established. 

a. Radiation, Sir Isaac Newton appears to have been the first who was 
led to apply a law of radiation to experiment. The statement of the law is 
given by him for the first time in a paper in the Philosophical Transactions 
for 1701 *, and is reprinted in his Opusculaf. 

* Philosophical Transactions, 1701, vol. xxii. p. 827. 
t Newton's Opuscula, vol. ii. p. 422, 



ON THE CONDUCTION OF HEAT. $ 

Newton s Imo of cooling, — The author is constructing a scale of tempera- 
tures ; he is comparing, for instance, the heat of boiling water with that of 
the human body. The comparison is made immediately, to the extent to 
which the thermometer affords an indication of the temperature ; beyond this 
it is requisite to have recourse to some process which involves computation ; 
and to this end Newton admits the hypothesis, to which we apply the de- 
signation given above. His words are as follows (translated) : " This table 
was constructed by the use of a thermometer and red-hot iron. By means 
of a thermometer I found the measure of the heat up to the point at which 
tin {stannum) is melted, and by heated iron I found the measure of the rest. 
For the temperature which heated iron communicates to cold bodies con- 
tiguous to it, in a given time, is as the total temperature of the iron. There- 
fore, if the times of cooling are taken in arithmetical progression, the tem- 
peratures will be in geometrical progression, and may be found by a table of 
logarithms." 

It is affirmed by most modern writers that Newton was led to this law by 
experiment. This was very probably the case, for to the extent of tempera- 
ture indicated by his thermometer it would be very nearly verified. 

The inaccuracy of this law was first pointed out by Martine*. He found, 
that although it appears very exact when the temperature of the heated body 
does not differ much from that of the surrounding air, yet when the tempera- 
tures differ considerably it is very far from being the case. Erxlebenf also 
proved that the law is at fault \n proportion to the excess of the temperature 
of the body. Mr. DaltonJ, in his ' New System of Chemical Philosophy,' ia 
a truly philosophical manner attempted to re-establish the law of Newton by 
altering the thermometric scale. The hypothesis on which he bases his views 
is, that the dilatation of all liquids is subject to the same law. MM. Dulong 
and Petit conceive that Dalton's views are untenable, arguing that, " even 
supposing the accuracy of the principles of this new scale to have been proved, 
we should be constrained to acknowledge that it does not satisfy the con- 
dition of rendering the losses of heat of a body proportional to the excess of 
its temperature above that of the air which surrounds it, or, in other words, 
that it does not re-establish the law of Richmann § ; for it would be necessary 
in that case that the law of cooling should be the same for all bodies, and our 
experiments rigorously prove the contrary || ." 

We presume MM. Dulong and Petit's argument to be based, not, as would 
appear from the phrase quoted, on the variability of the law of cooling, so 
much as on the fact that for different substances the two portions whose sura, 
according to these authors, constitutes the law, are affected with very different 
multipliers; so that their relative values depend altogether on the nature of 
the body. To this matter we shall return in the sequel^. 

M. de la Roche of Geneva** likewise pointed out the deviation from New- 
ton's law, at the same time admitting that it is sufficiently accurate to 212° 
Fahr., which is perhajis rather more than subsequent discoveries warrant us 
in assuming. 

We come now to the time when the law was established in its correct form, 
so far as we can see at present. The whole merit of the discovery is due to 

* Martine, Essays on Heat, 1740, p. 236, art. 4. 
t Novi Commentarii, Soc. Gott., vol. viii. p. 74. 
X New System of Chemical Philosophy, 1808, p. 12. 
§ Kraft and Richmann, Novi Commentarii, Petrop. i. p. 195. 
II Dulong and Petit, Journal de TEcole Polytechnique, 1820, torn. xi. p. 237. 
% Consult their Memoir, p. 190. 

** Journal de Physique, 1812, torn. Ixxv, p. 201, Prop. 6. Aunals of Philosophy, vol. ii, 
p. 100. 

b2 



4 REPORT — 1841. 

MM. Daloiig and Petit, to whom the Academy of Sciences awarded the 
prize in 1818, and whose admirable memoir ' On the Measure of Tempera- 
ture and the Laws of Communication of Heat' the reader will do well to con- 
sult*. All that we can do is to give a very brief outline of their researches. 
The first step requisite for them to take was the determination of a correct 
measure of temperature. To present to the eye an indication of the state of 
heat of a body the principle of dilatation has been most commonly applied, 
but it becomes a question to ascertain what substance will by its dilatation 
express the state of heat the most simply. MM. Dulong and Petit, having 
determined "that all the gases dilate absolutely in the same manner and by 
the same quantity for the same change of temperature," conclude that the air- 
thermometer is the best indicator of the state of heat. They argue, " that the 
well-known uniformity in the principal physical properties of all the gases, 
and particularly the perfect identity of the laws of their dilatation, renders it 
very probable that in this class of bodies the disturbing causes have not the 
same influence as in solids and liquids, and that, consequently, the changes 
in volume produced by the action of heat upon them are more immediately 
dependent on the force which produces them. It is therefore probable (they 
think) that the greater number of the phsenomena relating to heat will pre- 
sent themselves under a more simple form if we measure the temperatures on 
the air-thermometer. It is at least by these considerations (they inform us) 
that we have been determined constantly to employ this scale t-" Having 
thus settled that the air-thermometer is to be taken as the measure of tem- 
perature, they proceeded in the next place to obtain the laws of cooling in 
vacuo. And here we cannot but express our regret that the original unre- 
duced observations of the authors are not presented to the world in some 
work generally known. We have never seen them, nor are we sure that they 
have been published at all. We take the present opportunity of further ex- 
pressing our astonishment that experiments on which so much depends have 
never been repeated in this country. We do not know any more desirable 
exercise of the funds and energies of public scientific bodies than the repe- 
tition of all experiments, and the institution of others in a trying form, on 
which laws of nature have been partially or totally founded. In the case 
before us we do not doubt the accuracy or fidelity of the ingenious experi- 
ments, but we wish to be assured by cumulative evidence that the constant 
introduced into their law is determined with sufficient accuracy. To return 
from this digression. 

The velocity of cooling was experimented on by our authors by means of 
heated thermometers placed in a balloon nearly free from air ; but the ob- 
servations were subjected to two corrections. In the first place the stem of 
the thermometer without the balloon soon becomes cooled down to the tem- 
perature of the surrounding air. Every temperature observed therefore was 
too low by a number of degrees equal to that to which the mercury in the 
stem would dilate, when heated from the temperature of the surrounding 
atmosphere to that of the bulb. A correction on this account was applied to 
all the temperatures observed. The second correction was destined to re- 
duce the observations actually made on the mercurial thermometer to the 
corresponding indications of the air-thermometer. Besides these corrections, 
rendered requisite by the nature of the experiments, there was a third which 
arose out of the necessary imperfection of the vacuum. This was applied to 
the resulting velocities, and its value was ascertained by making correspond- 

* Annales de Chimie, torn. vii. p. 225, &c. Thomson's Annals of Philosophy, vol. xiii. 
p. 113, &c. Journal tie I'Ecole Polytechnique, 1820, torn. xi. p. 189. 
t Journal de I'Ecole Polytechnique, torn. xi. p. 232. 



ON THK CONDUCTION OF HEAT. 5 

ing experiments on vacuums of different degrees of imperfection, and tlience 
computing the amount of error introduced by the action of a known quantity 
of air. 

The result to which our authors arrived is expressed by the following law. 
" When a body cools in vacuo, surrounded by a medium whose temperature 
is constant, the velocity of cooling for excesses of temperature in arithmetical 
progression increases as the terms of a geometrical progression, diminished 
by a constant quantity." The formula which expresses the velocity of cool- 
ing is ma {a — l), where a is the same for all bodies, viz. 1*0077 or 
^°/ri65, denotes the temperature (marked by the air-thermometer and 
measured on the centigrade scale) of the vacuum in which the cooling body 
is placed, and I the excess of the temperature of the body above 9. 

On cooling in air or in gases. — The hypothesis on which was computed 
the velocity of cooling in air or any other gas, was, that the velocity might 
be divided into two parts ; — the one, that due to direct radiation in vacuo ; 
the other, that due to the actual presence of the gas. The gas was supposed 
not to influence directly the process of radiation, but to act in aid of it by 
conduction or convection, or a combination of both. Proceeding thus, MM. 
Dulong and Petit first verified the observation of Leslie, " that the loss of 
heat owing to the contact of a gas is independent of the state of the surface 
of the body which cools." They showed next, " that the velocity of cooling 
of a body, owing to the sole contact of a gas, depends for the same excess of 
temperature on the density and temperature of the gas ; but this dependence 
is such that the velocity of cooling remains the same so long as the elasticity is 
unaltered" They found also, "that the cooling power of a gas is, cceteris pa- 
ribus, proportional to a certain power of its elasticity, but that the index of 
the power varies for different gases;" and moreover, "that the velocities of 
cooling due to a gas increase in geometrical progression as the excesses of 
temperature increase in geometrical progression." 

We shall best understand the whole law of cooling by exhibiting it in the 
shape of a single formula. It is as follows : 

Y -m.. 1-0077^ (1-0077^ - 1) -{- n eP h^'^^^, where m depends on the 
nature of the surface, and n and p on the nature of the gas. is, as before, 
the temperature of the gas, and + S that of the cooling body ; e, the elas- 
ticity of the gas. 

If this be the law of nature, we can hardly term by the same word radiation 
the loss of heat in vacuo, and the loss due to the action of the surrounding 
air. We must therefore, for the present, confine our signification of this 
term to the former, and admit that results deduced from the hypothesis of 
radiation apply only to experiments carried on in a space free from air. 

b. Conduction. Ordinary experience teaches us that the power of con- 
duction differs in different substances ; and it is natural to suppose, and has, 
in fact, been universally admitted, that this difference is a difference in in- 
tensity only. It is assumed that one and the same law holds good for all 
bodies, but that a certain factor, on which the absolute amount of conduction 
depends, differs accoi'ding to the nature of the substance. But to define the 
law of conduction, which is the same for all substances, considerable diffi- 
culty has been experienced. Lambert*, and the other early writers on the 
subject, regarded the flow of heat as the flow of a fluid. But when we treat 
the subject mathematically, and regard the flow of heat as the flow of an 

* Act. Helvet., vol. ii. p. 172. 



6 REPORT — 1841. 

elastic fluid, considerable difficulties present themselves. We do not know 
that the difficulties are real ; we think, as Mr. Whewell hints*, that they are 
introduced by an arbitrary assumption concerning infinitesimal magnitudes. 
One difficulty is as follows : If heat flow from one point or place to another, 
the variation of temperature is a quantity of the first order ; whilst if we ob- 
tain the variation by estimating the gain and loss of heat which that point or 
plane receives, we shall find it to be a quantity of the second order. Biot, 
who in 1804 read to the Institute a short memoir on this subject fj was con- 
strained to leave his fundamental equation without demonstration on this 
account {. The difficulty is supposed to have been removed by Laplace §, 
who does indeed present reasoning bearing with some weight on the subject. 
But we could have wished that he had distinctly answered the following 
question. If three equal, small, contiguous slices of a bar be conceived col- 
lected each at its middle plane, will the quantity of heat which in a given time 
passes from the first to the second, or from the second to the third, depend 
on the (small) thickness of the slices or not ? Fourier doubtless saw that it 
would not, and therefore, instead of reasoning on the difference of heat be- 
tween two portions of the body directly, he fixes his attention on the Jlow of 
heat across a plane. His reasoning is as follows : — A homogeneous body is 
supposed to be traversed by two parallel planes whose distance is e, of the 
lower of which every point has the same temperature a, and of the upper a 
different and less temperature h. Then, if v represent the temperature at 
any intermediate point at the distance z from the lower plane, the expression 

a — h 

V ■= a — '■^— z being supposed to be once established as the law of the 

temperature at all points, no change will take place in the state of heat of the 
body II . To prove this he takes two points at equal distances from the plane 
whose temperature is v, the one above, the other below it, and shows that the 
excess of the temperature of the lower above v is exactly equal to the defect 
of temperature of the upper from v. He then concludes thus : " It follows 
that the quantity of heat transmitted by the lower point to the middle one is 
the same as that which the middle one transmits to the upper, for all the 
elements loldch concur to determine this quantity of transmitted heat are the 
samef^." Thus M. Fourier's hypothesis of conduction is, that the flow of heat 
depends on the difference of temperature ; or as he gives it, " the flow of heat 
across a given plane, whose distance from some fixed plane is a and tem- 
perature V, is proportional to - — " This we regard as the first law of con- 
duction. 

No doubt M. Fourier has confounded heat with temperature ; but this 
confusion is merely a confusion of terms ; the reasonings and results are un- 
affected by it. 

M. Poisson, founding his theory on molecular interchange, and having in 
view Dulong and Petit's law of radiation, admits another law of conduction. 
This law is thus expressed : " The change of heat between two points depends 
on the product of the difference of temperatures of those points, and of a 
function of their positions and temperatures **." In M. Poisson's earlier in- 

* History of the Inductive Sciences, vol. ii. p. 470. 
t It is printed in the BibUotheque Britannique. 
X See Biot, Traite de Physique, torn. iv. p. 669. 

§ Laplace, Memoires de rAcademie, 1809, p. 332. Connaissance des Tems, 1823, and 
Mecanique Celeste, liv. ii. || Fourier, Theorie de la Chaleur, p. 47. 

H Ibid, p. 49. ** Poisson, Theorie de la Chaleur, art. 48. 



ON THE CONDUCTION OF HEAT. 7 

Vestigations the latter factor had been regarded as a function of the positions 
of the particles only* ; although he Avas led by analogy to the adoption of the 
above law, as he himself informs us f , yet he does not appear to have adopted 
the law of Dulong and Petit itself as the law of conduction. He leaves it 
indeterminate, having found, as we shall show in another part of our report, 
difficulties in admitting such to be the case. 

Lastly, the author of the present report, in a short memoir which he read 
to the Royal Society of Edinburgh %, suggested the possibility of the ex- 
istence of a third law of conduction, differing considerably from either of the 
former as they are actually adopted, but which might be made to differ 
little from Poisson's by the change of a few of the quantities to which that 
author has assigned values. The law may be stated briefly as follows : — 
" The flow of a function of thermometric temperature across a given plane 
varies as the difference of the values of this function on the two sides of the 
plane." It will be seen at once that this law restores us all Fourier's con- 
clusions, provided we regard his phrase " heat " or " temperature," Avhich 
he uses indifferently, as signifying a given function of thermometric tempera- 
ture. These are the only laws of conduction which have been suggested : 
they are mere hypotheses. In seeking for a law of radiation we may have 
recourse to direct experiment, but here no such means are in our power. 
All that we can do is to experiment on the combined effects of radiation and 
conduction ; and then, supposing ourselves in possession of the effects due 
to the former, to eliminate them, and infer the law of conduction from the 
remainder. But this cannot be done without computation, and computation 
cannot be effected without formulae, which latter must be based on the hypo- 
thesis of conduction itself. Thus we are reduced to the indirect method of 
assuming the law, and testing by experiment the conclusions which spring 
from the assumption. We must prepare, therefore, to examine the results 
of analytical investigation applied to certain laws of radiation and conduc- 
tion which are at first conceived to be true, but only to be finally esta- 
blished by the conclusions themselves. Before we proceed, it will, perhaps, 
be as well to repeat that we have found two laws of radiation and three of 
conduction to exist as the assumed laws of nature. By the combinations of 
these laws we could conceive six different theories of heat to arise. Of these 
two would be obviously at variance with our present notions of fact ; the 
other four have to be examined. 

All the earlier theorists assumed, as we have already stated, the most 
simple axioms of radiation and conduction, viz. that the flow of temperature 
is proportional to the excess of temperature. Such being the case, we may 
venture to pass over the labours of Biot, Laplace, and others, not because 
they are unimportant, but because the same results are to be found in the 
more extensive and systematic writings of Fourier. In 1807 this philosopher 
read before the Institute a memoir, in which the subject was treated in a 
masterly manner, and the difficulties which had previously encompassed it 
were removed §. The Academy of Sciences, with the laudable design of 
inducing the author to prosecute his researches, proposed as the subject of 
the Prize Essay to be awarded in 1812, " To give the Mathematical Laws 
of Radiation and Conduction, and to establish them by experiment." Ac- 
cordingly, on Sept. 28, 1811, M. Fourier's second memoir was deposited^in the 
archives of the Institute. The prize was decided to have been gained by it, 

* Journal ile I'Ecole Polytechnique, torn. xii. p. 87. 

t Thuorie de la Chaleur, Preface, p. 6. 

X Proceedings of the Royal Society of Edinbiu'gh, Dec. 16, 1839, p. 2?9. 

§ Bulletia des Sciences, 1808, torn. i. p. 112. 



8 REPORT — 1841. 

but not without an expression of the restrictions which the Academy put on 
its favourable opinion. The committee appointed to examine and report on 
the memoir, consisting of Laplace, Lagrange and Legendre, whilst they 
agreed in proclaiming the novelty and importance of the subject, and in de- 
claring that the equations are the true equations required by the conditions, 
expressed a difficulty about the way in which they had been deduced, and 
added, that the means employed to effect their integration left much to be 
desired. Fourier never yielded to this judgment ; and accordingly he printed 
his memoir exactly as it was written in the memoirs of the Academy for 
1 825 and 1 826 : nor did he ever modify or extend his views, so far as we know. 
He published his Treatise on Heat in 1822, which does not essentially differ 
from his memoir. 

It is not necessary to trace all the circumstances which withheld from the 
world these important investigations for so many years. We must not lay 
all the blame on the Institute ; doubtless a part of it falls on Fourier himself. 
The accounts which had appeared were scanty. They will be found in the 
'Annales de Chimie,' iii. 250 (1816), iv. 128 (1817), vi. 259 (1817) ; ' Bulletin 
des Sciences de la Societe Philomatique', 1818, p. 1, and 1820, p. 60 ; the 
'Analyse des Trauvaux de 1' Academic,' 1820, Scc.hy Delambre. 

Whilst the memoir lay in the archives of the Institute, the labours of 
Dulong and Petit had, by the establishment of another law, rendered it de- 
sirable that the theorist should reconstruct his equations and extend his ana- 
lysis. We can understand well enough why M. Fourier did not attempt 
this. Whilst his own investigations lay unknown, he had no inducement to 
extend or continue them : far less was he likely to take in hand a totally new 
investigation which could hardly be expected to present results so beautiful 
and symmetrical, and must, from their further approach to a correspondency 
with the laws of nature, have withdrawn attention from his previous labours. 
But we are astonished that M. Poisson, who laboured successfully in this as 
in every other field of mathematical physics, did not see the necessity of 
adopting axioms conformable to fact. We suspect that he and Lame, and 
all the other writers who treated of the subject, were more anxious to pursue 
a line of investigation which led to symmetric formulae, than one which 
should lead to results conformable with the facts of experiment. 

The person who first attempted an investigation based on principles more 
approaching to the probable law of nature was M. Libri. His memoir was 
read to the Academy of Sciences in 1825, and is printed in the 'Memoires de 
Mathematique et de Physique ' *, and in ' Crelle's Journal ' for 1831, vii. 1 16. 

The grounds of his investigations are, 1. That extra-radiation follows the 
law of Dulong and Petit. 2. That conduction follows the law of Biot, La- 
place and Fourier. He confines himself to the solution of one problem, as 
the most simple that could be selected to illustrate his views. The problem 
is the determination of the temperature of a ring heated 'at one point. The 
author integrates the equation for the variable state of heat on the hypo- 
thesis that the variation from the ordinary results which is introduced by 
taking Dulong and Petit's law is a small quantity. Certain peculiarities in 
his process of integration have drawn the attention of those who are inter- 
ested in the subject to this memoir. The author of the present report was 
the first to find fault with M. Libri's solution in 1837 f. Others have, since 
that time, joined in the opinion ; amongst the rest M. Liouville. The paper of 
this author, read to the Institute, and published in his 'Journal des Mathema- 
tiques ' for 1838, has caused some little discussion on the subject, which the 
reader will find in the ' Comptes Rendus ' for 1838, 39 and 40. 

* Florence, 1829. f Theory of Heat, p. 69. 



ON THE CONDUCTION OF HEAT. 8 

We should not have thought it necessary to mention this subject were we 
not desirous of seeing the attention of philosophers directed to this branch 
of physics. It is extraordinary, that a theory, professing to be a physical 
theory based on experiment, should have been suffered to lie for twelve years 
hardly known in fact, but occasionally alluded to as complete and satisfac- 
toi'y. In the kindred science of optics half the time would have sufficed to 
attract the attention of the whole scientific world ; and experiment and analy- 
tical investigation would have been lavished on the subject. We hope M. 
Libri will be induced to pursue his investigations^ further, and to reduce the 
results to a tangible form. 

The next theory to be mentioned is that of Poisson. In his ' Theorie Ma- 
thematique de la Chaleur' (1835), he adopts the law established by Dulong 
and Petit for extra-radiation, and conceives that a similar law may apply to 
the interior transmission of heat. The hypothesis on which he proceeds re- 
lative to the changes of heat between all parts, the complication of his re- 
sults, and a degree of uncertainty which hangs over the law of change, 
render his work rather a display of analytical artifice than an attempt to 
build up a theory by applying to it the test of an examination by contrast 
with the facts it is designed to account for. It is to be regretted that M. 
Poisson, in turning his attention to the fundamental difficulties in the theory, 
did not adopt the plan of endeavouring, in the first place, to remove them, 
and afterwards to advance to the application of the same principles to the 
more difficult and complex questions which might present themselves. As 
it is, we can find in his work only one conclusion to which we can turn, in 
the present state of our knowledge, with the view of applying to it the test 
of experimental examination : this result we shall exhibit in its proper 
place. We have only to add, that M. Poisson's equation has been deduced 
by Mr. Rankine in the ' Edinburgh Academic Annual,' and applied to the de- 
termination of the temperature of a heated globe. 

Lastly, the author of the present report has suggested that it is proper to 
try a fourth theory, the last which the combinations of the laws of radiation 
and conduction admit of. It does not appear improbable, that although the 
flow of temperature does not depend on the dift'erence of temperature, the 
flow of heat should depend on the difference of heat, provided we regard 
heat as a certain state of the body different from temperature. This theory 
then rests on the hypotheses, 1 . That the variation of v due to cooling in 
vacuo depends directly on v, 2. That the flow of v across a given plane 
varies as the difference of the values of v on the two sides of that plane. 

Thus this theory coincides altogether with Fourier's, except that v is no 
longer the temperature, but a certain function of the temperature. The 

function appears to be z; = A (1 —a ~ ) + B*, where 6 is the temperature 
and a is Dulong and Petit's constant. 

These are the four theories which at present exist, each based on the com- 
bination of one of the two axioms of radiation with one of the three axioms 
of conduction. We propose now to write down some of the most import- 
ant and simple of the conclusions to which they respectively lead. 

I. Fourier's hypotliesis. That the flow of temperature depends directly on 
the difference of temperature, both within and at the surface of a body. 
As we have already stated that one of the formulae had been given by Biot 
prior to the appearance of Fourier's memoir, it will save confusion, if, not- 
withstanding, we make our references to Fourier's work alone. 

Formula 1. — The permanent temperature of an infinite homogeneous 

* Athenffium for October 24, 1840, and Report of British Association for 1840. 



10 REPORT— 1841. 

solid, bounded by two parallel planes, each of which is, and has been, for an 
indefinite time, kept at the same uniform temperature throughout, repre- 
sented for the one plane by a and for the other by h, is expressed by the 

following equation : u = a + z ; where v is the temperature at the 

e 

distance z from that plane whose temperature is a, and e is the distance be- 
tween the planes. (Fourier, Theorie de la Chaleur, Art. 65.) 

2. A very small square prismatic bar is kept heated at one end until the 
different parts of the bar have acquired a permanent temperature. That 
temperature, or rather, as it actually is, the excess of temperature above that 
of the surrounding medium, is represented by the equation, 

wt= Ac V A7+Be VJ7; 

where x is the distance of the point whose temperature is v from the heated 
extremity of the bar, / is a side of the section, and h and k the coefficients 
of radiation and conductivity of the bar. 

Cor. If the bar be supposed very long, B must be equal to 0, and v = 

„ /2h 

Ae~'^V*T. _ 

Here A represents the heat of the extremity, and a / _ is a quantity 

which must simply be determined by experiment. (Art. 76.) 

3. The permanent state of temperature of a ring is represented hj v = 

A a~ + B a , where x is the distance of the point under consideration 
from some fixed point, measured along the arc which passes through the 
centre of the generating circle. (Art. 106.) 

Cor. If points be taken at equal distances along the axis of the ring, the 
ratio of the sum of the temperatures of the first and third to the temperature 
of the second, is the same, whichever point be taken first. (Art. 107.) 

4. The temperature at any point of a ring which has been heated at one 
point to a stationary temperature, and is then suflPered to cool, is represented 

I. r. "''"ivTri cosa;e "''' cos2a;e"" ^^'^^ cos3a;e~^^** 

byt; = 2e M|- -^^-^ + "S^+T " ^mHT 



\ (Art. 242.) 



5. As the time increases, the law of temperatures in a ring tends to become 
such that the sum of the temperatures at the opposite extremities of a dia- 
meter is equal to 2 « ~ ' ; which shows that the sum is the same at the ex- 
tremities of whatever diameter we estimate them. (Art. 245.) 

II. Libri's hypothesis. That the interior conduction follows Newton's, and 
the extra- radiation Dulong and Petit's law. The author has only applied 
his analysis to the motion of heat in a ring. The conclusion to which he 
arrives is the following : 

6. If a ring be heated at one point and then left to cool, the sum of the 
temperatures at a given instant at the two extremities of a diameter is the 
same for every diameter that may be taken. 

This result, which is only approximate, is not adapted for testing the truth 
of the theory. It is, however, quite independent of any considerations re- 
specting the mode by which the equations may be integrated. 

The author of the present report has applied Libri's hypothesis and method 
to the solution of the same problem. He finds that 

7. The effect of Dulong's law is, that the velocity of cooling diminishes 



ON THE CONDUCTION OF HEAT. 



11 



more rapidly than it would if Newton's law were true. Nothing else is 
altered. (Theory of Heat, p. 75.) 

This result, it must be confessed, is deduced from the omission of many 
terms in the equation in order to effect an approximation. It can hardly be 
regarded as a tolerable expression of fact. 

III. M. Poissons hypothesis. That extra-radiation follows Dulong and 
Petit's law, whilst conduction follows an analogous law, — the flow of tempe- 
rature depending on the product of the variation of temperature, and a 
function of the temperature. In M. Poisson's large work will be found the 
solution of a considerable number of the resulting equations ; but the solu- 
tion is in general approximate, and effected in such a manner as to reduce 
the hypothesis actually to M. Fourier's hypothesis. We find very few prac- 
ticable results in the work, derived from the proper axioms on which it pro- 
fesses to be founded. One only can be given which will serve the purpose 
we have in view. The equation which gives the permanent state of heat in 



an 



uniform prismatic bar is — ( ^ -j — I = — p (y -- '(); (Art. 1 1 8.) 



d V 
where k and p are functions of the temperature, such that k j— and p v 

respectively represent the flow of heat in a small time (considered as unity) 
within and on the surface of the body ; <^ is the temperature of the surround- 
ing vacuum. 

M. Poisson assumes that u — i^ or v is small, or perhaps rather (as appears 
to us) that certain multipliers of this quantity are small, so that k and p 
may be expanded in terms of v, and high powers of this quantity may be 
omitted. He thence deduces the following equation as expressing the per- 
manent temperature of a bar heated at one extremity ; the length of the bar 
being indefinitely great : 

8. »= 1 (y -2 m) 0e~^*' H — - (y - 2 m) e ~^^ "^ ; where y 

= log^ 1-0077, and m is undetermined, but depends on the manner in which 
the conductivity varies with the temperature. (Theorie de la Chaleur, Art. 
105.) 

On this result we must make some remarks. In the first place, we con- 
ceive that by a slip of the pen M. Poisson has given a wrong value to y ; 

it appears to be properly -— log 1*0077. The quantities y and m result 

2 e 
from the expansion ofp and k in the form p + p y u, k + k m u. In the next 
place, we find some difficulty in understanding what the quantity m actually is 
supposed to be. If M. Poisson conceives, as he leads us to believe in his pre- 
face (p~. 6), that Dulong and Petit's law is applicable to the interior as well 
as to the exterior flow of heat, we cannot see how he regards m as undeter- 
mined. We should have thought, that if it be admissible to expand in terms 
of V at all, m must have been known. Perhaps M. Poisson saw a difficulty 
in admitting this, arising from the circumstance that y — 2 m might (and it 
appears to us it would) turn out to be negative, and thus disprove the whole 
theory. The phrase which M. Poisson makes use of is this : Quant a la con- 
stante m, elle depend de la maniere dont la conducibilite varie avec la tempe- 
rature ; et sa valeur n' est pas non plus connue. (p. 255.) 

IV. The theory suggested by the author of this report adopts all the re- 
sults of the hypothesis of Fourier. In this case v will not express the fem- 
perature as measured by an air-thermometer, but a certain function of that 
temperature. We have already given the function which appears to us to be 
the proper one. It is deduced by the following reasoning. Let represent the 



12 REPORT — 1841. 

temperature, or rather the excess of temperature above that of the sur- 

d V 
rounding vacuum ; then since Fourier's equations hold good, we have — = 

— av, where « is a quantity which depends on the radiating power. 
But by Dulong and Petit's formula, 

dv a V 



"d6-i3\e_^' 

and log V = —, log A (1 — a~ ) 

^ 10 log^ a *= ' ^ 

jS logg a 
V « =A(l-a~% 
If /3 log a = a, this equation is reduced to 

To the collection of formulae which we have extracted from the writings of 
Fourier, Poisson, and Libri, we may add the following, which apply to ex- 
periments of the simplest kind. 

9. On Libri's hypothesis, the permanent state of temperature in a small 
uniform bar of indefinite length heated at one end is represented (approxi- 
mately) by the equation 

A- log^ a _9„r 

v—Ke ■^ + g 

The demonstration of this proposition is as follows : 
The equation of motion is 

- — = X (cp — 1), where a = \/ 1*165 according to Dulong and Petit. 
dx- ^ 



By expansion, — = \^v log^ « + ^ i^^Se «)" f 



o2 
= 9""" + "^ loge « • '"- nearly. 

Assume v = A e~^ + V, 

CI CC" it 

d~ V o^ 

consequently ^— J- =5^2 V + -^ log^ a . A- e"^^^;^ 

whence V = :^L2^?ile- 2-7^ 
6 

AMog a 

and V = Ae-S^ + -5£_ e-2^cr_ 

b 
10. On Fourier's hypothesis, the temperature at the extremity of a like bar, 
when its length is not sufficiently great to be regarded as infinite, is t;' = C u, 
where u is the temperature of the heated extremity, and C is a constant, not 
depending on u. 

The equations of motion are 

d'~v 2 h J dv , h * , . „,, 

-j—l = -T-T V ; and -z — \- —v = 0^) at the extremity of the bar. 

■* Fourier, arts. 74 and 124 ; Kelland, arts. 53 and 57. 



ON THE CONDUCTION OF HEAT. 13 

The solution of the former is 

which, when substituted in the latter equation, gives for the extremity of the 
bar whose length is b, 

Be ^ ki — Ke ^ ki t^^ 

V'ik + Vhl 



and 



whena; = 0, M = A-^ 1 H -= :^^-=e v */ > 

.'. A = E(V2lt- V7ri)u; 
abbreviating the reciprocal of V^k + ^hl 

, 91 /2A 

^{^/^lk~ Vhl)e ^V*7byE. 
Hence 

When x=.b, v' = C ti. 

11. Cor. The temperature at any point of a bar of finite length is repre- 
sented by 

The expression shows that the temperature is the difference of two quan- 
tities ; the one due to the heating at the one extremity, and the other follow- 
ing a corresponding law, and due to the cooling at the other extremity of the 
bar. 

12. On Libri's hypothesis, the expression for the temperature at the extre- 
mity of a bar heated permanently at the other extremity is 

"o 

where u is the temperature at the heated extremity of the bar, and p, q, p 
q , are constants. This proposition is of some importance, but from the 
want of experiments we do not think it necessary to exhibit the values of the 
constants in full. 

The demonstration is as follows : since 

at the extremity of the bar, we obtain 

6 

. B-log,a -2o(b-x) , „, 
+ 2£_e "^^ ^ — ABlog^a. 



14 RRPORT — 1841. 

2. From the second equation 

9+f 3 (5- +/)' ' 

4 2 

Also u the temperature at the heated extremity is of the form 2p A + — : 
.'.A=-pq+ Vp-.q'i + qu 

A^ 
and v' = 2 jtJ^ A -\ , in which p^ and q^ differ from p and q in not con- 

taining e^ , e~^ ; or may be deduced from them by writing b = ; 

••• V = 2p^{ ^p^q«-+qu -pq}+ {^tSl+JU^^llll, 

13. The expression for the permanent temperature at one extremity of a 
bar heated at the other extremity, determined on M. Poisson's hypothesis, 

differs from the foregoing only in having - — A^ instead of °^ A- 

^ 6 

as the coefficient of e^ ^ ^* ' ^\ y-2m ^^ .^^^^^^ ^^ log^g ^^ ^^ ^^^^ ^^ 

3 6 

g—g \ —^) ^^(j 2 y instead of log^ a as the coefficient of the constant term in v. 

14. The expression for the same permanent temperature derived from the 

fourth hypothesis is 1 — a~ = C(l —«"""). 

15. When a bar, so large as that it may be considered infinite, is heated 
at one end to the constant temperature a, and kept at the other to the con- 
stant temperature b, as assumed in formula 1 , the state of temperature at any 
point, as deduced from M. Poisson's theory, is given by the equation 

^_a+'-^(v"--a"-) + (a-b+'^ o^^^^) - = 0. 
2 2 e 

The proof of this proposition is as follows : 

Since the bar is very large, the effect of radiation is zero (at least near the 

centre of the bar). Therefore the equation of motion is -7— • I -r^ )^^^' 

j,dv 

or « -7— = c. 

a z 

Now Poisson's approximates by supposing k' =.k -\- kmti. 
Hence the equation is immediately integrable, and the result is as above 
given. 

16. The corresponding equation due to the fourth hypothesis is 

-a -b 
— V —a a — a 
\—a =1— a +— z; 

the a which is affected with an index being Dulong and Petit's a. 

We have not thought it relevant to our present subject to point out the 
difference which exists between hypotheses III. and IV.; as, however, we have 
given only approximate formulae corresponding with the former hypothesis, 
it may be proper to mention, that, for expressions not involving the time, the 
essential difference between the formulae will be seen by the difference of 
sign of the quantity which corresponds with m. It will be seen that on hy- 



ON THE CONDUCTION OF HEAT. 15 



pothesis III. the form of the result in this case is « + — v'^ = a — fi z, whilst 
the approximate form on hypothesis IV. is 

V Z)- = a — /3 Z. 

We may add, that if we assume k= aa^, the correct equation for hypothesis 
III. will be a a rf j; = c, which gives 

— a =: C X + c'. 



log a 

When the time enters into the expression, no analogy exists between the 
formulae, deduced on the two hypotheses. 

If we were in possession of a number of experiments adapted for the purpose, 
it would be desirable that the constants in formula (12) and (13) were more 
fully expressed. When such experiments shall have been made, a very little 
trouble will suffice to effect this. Should it appear, moreover, that experi- 
ments bearing on formulae different from that which we have given can be 
more easily performed, the corresponding expressions may be readily deduced 
from the equations given above. 

II. We proceed now to the second division of our report. We have to 
inquire to what extent theory has been tested by experiment. In prosecuting 
this inquiry we shall be led to examine for ourselves such of the formulae as 
appear to be parallel to the experiments we possess. We hope by so doing 
to point out the facility with which experiment is made available, as well as 
practically to exhibit the neglect or want of attention which this department 
of science has suffered. 

We turn first to the experiments described in M. Biot's ' Traite de Phy- 
sique' (1816), tom. iv. Those which follow were made with the design of 
testing the formula for the permanent state of heat at any point of a very 
long bar heated at one end. The author himself compares them with the 
formula, which, as we have said before, was discovered by him, but never 
completely demonstrated. 

(1 .) The first experiment was made with a bar of iron, plunged at one extre- 
mity into a bowl of mercury at 102§° cent. : along the bar were ranged eight 
thermometers at various distances from each other. The observations were 
made after the state of the temperature, as indicated by the thermometers, 
had arrived at permanency ; and the length of the bar was so great that the 
temperature of its free extremity did not sensibly differ from that of the air. 
The following table contains the i-esults of this experiment reduced to the 
centigrade scale. The distances are expressed in decimetres, and the num- 
bers in the third column express the permanent state of the excess of tem- 
perature of the corresponding points of the bar above that of the surrounding 
air. This latter temperature was 1 6^°. 
No. of therm. Dist. from Mercury. Excess of temp, above that of the air. 

86-25 

1 2-115 29-375 

2 3-115 17-5 

3 4-009 11-25 

4 4-970 7-1875 

5 5-902 4-6875 

6 7-777 2-1875 

7 9-671 1-25 

8 11-556 insensible 



16 REPORT — 1841. 

The distance of the end of the bar from the mercury was ST'S^S deci- 
metres. 

I. The following table exhibits the temperatures which should exist, as 
calculated by the Cor. to formula 2 ; i. e. on the first, or Fourier's hypothesis. 
It is copied from Biot, vol. iv. p. 672, and reduced to the cent, scale. The 
constants are determined by thermometers 1 and 3. 

Therm.... 12 3 4. 5 67 

Result.... 85-6 29'375 17-7 11-25 6-9375 4--3125 1-6625 -6375 

II. Let us calculate the temperatures on Libri's hypothesis, by means of 
formula 9. 

We have log^ a = -00763606, and if we denote one-sixth of this by c, our 
equation becomes 

V = A e~^^ + c (A e'^'^y, which, being solved, 

4 -gx V^cv + \- 1 

gives Ae " := ; 

2 c 

V'4cj;„ + 1 — 1 



and therefore e~^*^*'3-^i)= 

'V4c»i + 1 — 1 

These two equations determine g and A by means of the first and third 
thermometers; viz. 

e ^ = -6093, and A = 80-855. 

The results of the calculation are the following : 

12 3 4 5 6 7 

89-2 29-375 17-6 11-25 6-95 4-358 1-72 -67 

III. On M. Poisson's hypothesis we have formula 8, viz. 

« = |l - y (y - 2»0 }0e-^'' + y (y-2m)e 2^*': 

where d is the temperature at the heated extremity of the bar, and y, as cor- 
rected above, is -OOSSIS. To compare this formula with experiment, we have 
supposed that g has the same value as we found it to have according to the 
preceding hypothesis. This supposition cannot, to any considerable extent, 
affect the results ; and we could not obtain g by any other direct means. We 
get from thermometers and \, y — 2m = -00153, and thence obtain the 
following table of results : 

1 2 3 4 5 6 7 

86-25 29-375 17-78 11-36 7-05 4-43 1-75 -69 

IV. Lastly, on the hypothesis that the flow of v is proportional to v, both 
within and at the surface of the medium. We reduce v to thermometric 

temperature by means of the equation t» = A (1 — a~ ) which is not strictly 
accurate except for the air thermometer ; and we determine the constants 
from thermometers 3 and 5. Tlie following are the results : 

12 3 4 5 6 7 

90-3 27-7 17-2 11-25 7-19 4-6875 2 -86 
It may be proper to remark, that although we have adopted MM. Dulong 
and Petit's value of a, we are aware that for radiation in air, so far as the 
formula approximates to the circumstances, this value of a is too small. 
(2.) The next experiment given by M. Biot (p. 673) is the following : 
A bar of iron was held for many hours plunged in melting lead. The ves- 
sel containing the lead was heated from below by means of a lamp and cur- 
rent of air. To prevent the temperature from increasing, a small bar of 



ON THE CONPUCTION OP HEAT. 17 

unmelted lead was kept constantly in the vessel. The temperature of the air 
was kept uniformly at 18° '125. The unit of length was taken as the distance 
between the first and second thermometers. The following table contains 
the results : 

No. of therm. Dist. from extremity. Temperature above air. 

1 2-23077 76-875 

2 3-23077 47-1875 

3 4-12019 29-375 

4 5-08172 17-8125 

5 6-02883 10-625 

6 7-89903 3-75 

7 9-78363 1-5625 

I. The result of calculation on the first hypothesis, the errors being ar- 
ranged so that there shall be the smallest possible total error amongst the 
first four thermometers, is given by M. Biot as follows : 

1 2 3 4 5 ■ 6 7 

77-575 46-7625 29-275 17-975 11-125 4-3125 1-6625 

II. On the second hypothesis the values of the constants are 

A = 206-9 and log e~^ = — -20955, 
as determined from the first and third thermometers. The table is as follows : 
1 2 3 4 5 6 7 

76-875 46-07 29-375 18-22 11-44 . 4-6 1-85 

III. By the third hypothesis, retaining the value of ^ given by the second, 
we get y — 2 »t = -003206, a result probably too great ; and there arises the 
following table : 

1 2 3 4 5 6 7 

76-875 47-76 29-375 18-23 11-45 4-6 1-85 

IV. The computations on the fourth hypothesis give 

12 3 4 5 6 7 

76-875 45-2 29-375 18-74 12-34 5-73 2-45 
By selecting other observations to determine the constants, we might, had 
it been requisite, have made the results more conformable in this case. 

(3.) M. Biot's third experiment was made on a bar of copper, plunged at one 
extremity into melting lead. It carried fourteen thermometers, of which, 
however, eleven only were available. The unit of distance was 101 milli- 
metres, and the temperature of the surrounding air 15-75°. The following 
table exhibits the result : 

No. of therm. Dist. from extremity. Temperature above air. 

4 5-25 80-5 

5 6-25 65-75 

6 7-25 53-75 

7 8-25 43-75 

8 9-25 • 35-5 

9 11-25 24- 

10 13-25 15-7 

11 15-25 Il- 
ls 17-25 7-5 

13 19-25 5-25 

14 21-25 3-75 

I. The results of M. Biot's computation, so as to give the smallest possible 
amount of error amongst the thermometers 4, 5, 6 and 7, are 

4 5 6 7 8 9 10 11 12 13 14 

80-6 65-78 53-82 43-8 35-75 23-81 15-85 10-56 7-03 4-68 3-12 
1841. c 



18 REPORT — 1841. 

II. On the second hypothesis A = 199-57 and log e~^ = — '08278, and 
the following are the results : 

4-5678 9 10 11 12 13 14 

80-5 65-34. 53-32 43-6 35-72 24-07 16-3 11-06 7-52 5*12 3-49 

III. M. Poisson's method, when the value of e~^ deduced from the pre- 
ceding hypothesis is retained, gives y — 2m =: -0031825 ; and we have 

4 5 6 7 8 9 10 11 12 13 14 

80-5 65-55 53-5 43-75 35-84 24-15 16-35 11-09 7-54 5-15 3-5 

IV. The fourth hypothesis gives 

4 5 6 7 8 9 10 11 12 13 14 

84-9 67 53-75 43-51 35-5 24. 16-45 11-39 7-9 5-5 3-8 

The next series of experiments similar to the above we obtain from the 
work of M. Despretz, entitled ' Traite de Physique.' The author read be- 
fore the Academy of Sciences in 1821 a memoir, the object of which is to 
measure in a number of substances the conductive power relative to heat. It 
is published in the ' Memoires des S^avans Etrangers.' An account of it ap- 
pears in the ' Annales de Chimie,' t. xix. (1821) p. 97, by M. Fourier, and it 
is extracted in works referred to above (1825). We have added the exa- 
mination of the four formulae by means of these experiments. We shall find 
that they all come very wide of the results, even in cases differing in no ap- 
parent particular from those given by M. Biot. This is remarkable, for all 
the formulas agree well with M. Biot's experiments. To what circumstance 
can we attribute this fact ? It cannot be supposed that the presence of the 
air should vitiate one series of experiments without affecting the other, in 
which everything else is similar. We can only suggest, that the bars whose 
conducting powers were examined, were not sufficiently long to be regarded 
as infinite. Unfortunately M. Despretz does not mention their length. The 
experiments were as follows : 

(4.) The stationary excesses of temperature above that of the air, at dif- 
ferent points of a bar of copper taken at equal distances from each other, 
were found to be as follows : . 

No.ofther.... 12 3 4 5. 6 

Exc.oftemp. 66-36 46-28 32-62 24-32 18-63 16-18 
The temperature of the air was 17-08°, and the distance between tAVO con- 
secutive thermometers ten centimetres. 

The following are the calculated results, by the four hypotheses respect- 
ively, using in each case the results of the first and third thermometers for 
the determination of the constants. 

I. 1 2 3 4 5 6 
66-36 46-45 32-62 22-83 15-98 11-19 

II. Here e~^-714 and A = 61-54. 

1 2 3 4 5 6 

66-36 46-45 32-62 22-83 15-98 11-19 

III. e~^is assumed to be equal to -714, and y — 2 w is determined to be 
.003271. 

12 3 4 5 6 

66-36 46-28 32-62 23 16-3 11-47 

IV. 1 2 3 4 5 6 
66-36 46 32-62 23-5 17-1 12-5 

(5.) A bar of iron circumstanced as the preceding. The temperature of the 
air was 17-34°. 

No. of therm.... 12 3 4 5 6 

Excoftemp.... 62*9 36-69 20*52 12-32 8-19 6-61 



III. Assumes log e ^ = — '22408, and gives — (y — 2 m) = 4"683. 



ON THE CONDUCTION OF HEAT. 19 

Calculations. 

I. 1 2 3 4 5 6 
62-9 35-92 20-52 11-72 6-7 3-83 

II. Gives e~^ = -589, A = 58*7, and 

1 2 3 4 5 6 

62-9 36-37 20-52 12-17 7-5 4-2 

III. Assumes e"^ = -589, and gives — (y — 2 »J) = 5-2705. 

1 2 3 4 5 6 

62-9 35-77 20-52 11-98 7 4-1 

IV. 1 2 3 4 5 6 
62-9 38 20-52 12-28 7-4 4-7 

(6.) A bar of pewter. The temperature of the air = 17-34°. 
No. of therm.... 12 3 4 

Exc.oftemp.... 63-41 35-17 21-52 15-52 

Calculations. 

I. 1 2 3 4 
63-41 36-93 21-52 12-5 

II. Gives log e~^ = — -22408 and A = 58-83. 

12 3 4 

63-41 36-69 21-52 12-73 

3 
12 3 4 

63-41 36-72 21-52 l2-7 

IV. 1 ^3 4 

63-41 36-14 21-52 13-18 

(7.) A bar of zinc. The temperature of the air = 5-62°. 

No. of therm.... 12 3 4 

Excoftemp.... 64-17 38-02 25-43 17*93 

Calculations. 

I. 1 2 3 4 
64-17 40-4 25-43 16-01 

II. Gives log e~^ = - -19184, A = 59-64. 

12 3 4 

64-17 40-21 25-43 16*17 

III. Assumes log e~^ = — -19184, and gives — (y — 2 w) = 4*656. 

12 3 4 

64-17 40-2 25-43 16*18 

IV. 1 2 3 4 
64-17 39-69 25-43 16-6 

(8.) A bar of lead. The temperature of the air = 17-12°. 

No. of therm. ... 1 2 3 4 

Excoftemp.... 65-13 29-42 14-93 9-99 

CalculaHo7is. 

I. 1 2 3 4 
65-13 31-18 14-93 7*18 

II. Gives log e"*' = - -30776, A = 60-45. 

12 3 4 

65-13 30-89 14*93 7*38 

c2 



20 REPORT — 1841. 

III. Assumes log e ^ = — -50776, and gives — (y — 2 wi) = ^'Sll. 

1 2 3 4 

65-13 30-9 14-93 7-27 

IV. 1 2 3 4. 
65-13 30-12 14-93 7*5 

(9.) A bar of white marble. The temperature of the air = 17-15°. 
No. of therm. ... 12 3 4 

Exc. of temp. ... 63-91 6-08 1-95 1-47 

Calculations. 

I. 1 2 3 4 
63-91 11-16 1-95 -3406 

II. Gives log e~^ = - -74249, A = 59*40. 

12 3 4 

63-91 10-9 1-95 -352 

no 

III. Assumes log e = — -74249, and gives -— (y — 2 wi) = -644. 

1 2 ' 3 4 

63-91 11-35 1-95 -379 

IV. 1 2 3 4 
63-91 10-18 1-95 -37 

Of the other formulae ■which have been tested by experiment we do not 
make much account, since it is our impression that the experiments were con- 
ducted rather with a view to illustrate the formulae than to try the validity 
of the principles on which they depend. We instance the following : it is 
taken from Fourier's Memoir, which contains several others, ' Mem. de I'ln- 
stitut/ tom. V. p. 217. See also Kelland, 'Theory of Heat,' p. 60. 

Three thermometers were placed at different points of a solid ring, at in- 
tervals of one-eighth of the circumference : a fourth was so placed that the 
third lay midway between it and the first. The temperatures observed were 
66°, 50^2°, 4^*°, and 34-353° + 17f°, respectively. 

The equation which results from formula (3) is — = I — ) — 2, 

where v^, v^... are the excesses of temperature of the different thermometers 
above that of the air. 

By computation, it appears that the first side of this equation is 3-140, and 
the second 3-143, a difference hardly appreciable. 

The second and third hypotheses give formulse which are merely correc- 
tions on the first. In this case, therefore, no correction is required. 

In computing the result on the fourth hypothesis, our equation is 



l-a~^'+ 1 -a~^' ^ ( 1 -g—' + l-a—a y_^^ 
1 - a-^' 



f l - a~^' + 1 - a-^' X 
V 1 - a-'-^ ) 



and the first side is equal to 2-96, the second to 2-875 ; a coincidence which, 
though not so close as the former, is very far within the error due to the 
effect of the air. We are almost inclined to believe that the veiy closeness 
of the coincidence by the former process proves the incorrectness of the for- 
mula to represent what it is intended to express. 

We are now, in the last place, to exhibit the results of an experiment of a 
different kind, and one which, had it been well made, we should have deemed 
most important. It is taken from M. Biot's work, 'Traite de Physique,' iv.676. 



ON THE CONDUCTION OF HEAT. 21 

(10.) A rod composed of a mixture of tin and bismuth in equal portions, 
which melts at the temperature of boiling water, was plunged at one extre- 
mity into a basin of mercurj'. The mercury was kept successively for a long 
time at different constant temperatures, by means of a lamp placed below it. 
A thermometer was adjusted to the other extremity of the rod, in a little cap- 
sule filled with mercury. Observations of the temperature indicated by this 
thermometer, corresponding Avith each stated temperature of the mercury in 
the basin, were made, when the state had become stationary. Tlie following 
table exhibits the corresponding excesses of temperature of the mercury and 
of the thermometer above that of the air. The latter was 20°. 



Excess of temp, at heated end 
Corresp. excess at other extr^. 



10-25 19-75 29-25 49 69-75 80 
3 5-5 8 10-5 11-75 12-5 

Before we compare this table with theory, it is right that we express our 
belief that there has been some mistake in the obsei-vations. We think this 
will be made out when it is seen that the following is the order of elevations 
of the upper thermometer, due to elevations of temperature of the heated end. 

For the first 10°-25 the thermometer rose 3°; 

For the second 9°-5 the thermometer rose 2°-5 ; 

For the third 9°"5 the thermometer rose 2°-5 ; 
in which the rise of the thermometer is nearly, but not quite, proportionate 
to that of the mercury ; but 

For the fourth 19°-5 the thermometer rose only 2°-5. 
This we think very unlikely. We should expect to find the proportion of the 
increase of temperature of the thermometer to that of the mercury continually 
diminish as the absolute temperature increases. The following are, however, 
the ratios as given by the above table : 

1 J_ J_ J_ _L I 

3-146' 3-8' 3-8' 7-9' 16-6' 13-66' 
If this be correct, the law is discontinuous. 

Calculations. 
M. Biot gives the following results as calculated by an empirical formula : 
12 3 4 5 

3-7 6-18 8 10-37 11-75 

I. From formula \0,v=^Cu. 

12 3 4 5 6 

3 5-78 8-56 14-34 20-41 23*41 

II. and III. On Libri's or Foisson's hypothesis we have approximately 
(from 12 and \S)v = Cu — 'D u'^. 

If we apply experiments (3.) and (5.) to obtain the constants C and D, 
there results 

1 2 3 4 5 6 

4-06 5-86 8 10-03 11-75 12 

IV. 1 2 3 4 5 6 

2-9 4-61 6-66 10-5 14 15-68 

It must be observed here, that we have only one constant to be determined 
by experiment. We must not expect, therefore, to find so close an agree- 
ment as when we have two. 

We are not ignorant that there are a vast number of experiments on radia- 
tion and conduction to which we have not referred. Our reason for omit- 
ting the mention of some of the most valuable is, that we desire to confine 
our attention strictly to the matter in hand — the examination of theoretical 
formulaj by experiments calculated to test their accuracy. 



22 



REPORT — 1841. 



III. We hasten, then, to the third part of our Report. We propose very 
briefly to reflect on the consequences deducible from the computations we 
have entered into ; and to conclude by adding a few remarks tending to sug- 
gest the proper mode of conducting experiments which shall serve a better 
purpose in eflecting the object of establishing theory. We may observe then, 
1st, that experiments on the permanent state of temperature at different points 
of a long bar of a good conducting substance, and which radiates into air, 
are utterly valueless in this matter. To prove this, we will write down the 
difference between the calculated and observed values of the temperature for 
a few cases. 

Exp. I. 



Therm. 





1 


2 


3 


4 


5 


6 


7 


Formula I. 


■65 





•2 





•25 


•375 


•525 


•6125 


II. 


2-95 





•1 





•9275 


•3275 


•4675 


•58 


III. 








•28 


•11 


•1375 


•2575 


•3375 


■56 


IV. 


4-05 


1-675 


•3 





•0025 





•1875 


•34 



It is altogether impossible to decide which is the best formula from these 
results. Apparently Formula I. is as good as any of them, and yet we are 
sure, a priori, that it is absolutely erroneous. The ratios of the error to the 
whole temperature when greatest are, for the different formulae, 

I. ^49, II. -465, III. ^458, IV. -272. 

These ratios are very considerable, and as they all arise at the point of 
greatest distance from the heated extremity, they prove clearly enough that 
the effect due to the presence of the air is far greater than that which arises 
from the diff'erence of radiation between Newton's law and the law of nature. 
But even if experiments of this kind were made in a vacuum, it is probable 
that the law of change would be found to remain so uniform as to admit of 
its being represented by either of the equations resulting from the second, 
third, or fourth hypothesis. Nor will our conclusions be more satisfactory 
on referring to M. Despretz's experiments. Let us write down the errors in 







Exp. 


V. 








Therm. 


1 


2 


3 


4 


5 


6 


Formula I. 





•77 





•6 


1^49 


2^78 


II. 





•32 





•15 


•69 


2^41 


III. 





•92 





•34 


M9 


2^51 


IV. 





1^32 





•04 


•79 


P91 



The maximum ratios of the error to the whole temperature are 

I. ^42, II. -36, III. ^37, IV. -28. 

We must remark again, that this experiment, as contrasted with the fore- 
going, presents us with most anomalous results. Both were made on a bar 
of iron ; the temperature of the surrounding air was nearly the same in both ; 
the extreme temperatures of the former lie beyond those of the latter on each 
side ; and yet the former verifies, or nearly so, all the formulae, — the latter 
disproves them all. We trust neither ; nor do we think the difference can be 
attributed to the coating with which the iron was furnished in the second 
experiment, although that might produce some effect. We feel, therefore, 



ON THE CONDUCTION OF HEAT. 



23 



utterly unable to draw any conclusion from these experiments. We shall 
experience the same difficulty if we proceed to examine the other results in 
the same way. If we confined our attention to experiments (1.), (2.) and 
(3.), we might conclude that all the formulae are correct ; if to (8.) and (9.), 
we should certainly conclude that all are incorrect. Nor is it easy to say 
which is the best from the former test, or which is the worst from the latter. 
Seeing, then, that agreement with experiment is no test of truth, it is not too 
much to argue that disagreement is no test of error. We must eliminate the 
efiect of the air, or be provided with experiments in vacuo, before we can 
form our conclusions, unless we can be furnished with experiments of a much 
more searching character than these. 

2. It is hardly necessaiy to call attention to the insufficiency of the class 
of experiments which was made by M. Fourier, and of which we have exhi- 
bited one specimen. The results for the ring, it is true, are not so obvious 
that they might be deduced from popular reasoning, and we must give M. 
Fourier great crpdit for selecting these results in order to show the agree- 
ment of his theory with experiment ; but as we are now in want of a means 
of disproving rather tlian of establishing theories, we must look, for results of 
a totally dift'erent character. We shall point out where such are to be found 
by and by. 

3. We think we may consider that experiment (10.) shows the inaccuracy 
of the first formula ; it fails, however, to give any preference to one of the 
other three. The table of errors is as follows : 



No. 


1 


2 


3 


4 


5 


6 


I. 





•28 


'6Q> 


4.-84 


8-66 


10^91 


II. & III. 


1-06 


•36 





•53 





•5 


IV. 


•1 


•89 


1-34 





£•25 


3-18 



*rhe maximum ratio of error to the whole temperature is 

I. -87, II. & HI. -35, IV. -25. 

It is needless to comment on these results. None of them are sufficiently 
close to warrant any favourable conclusion, and the first is so wide, that, were 
there no other reasons, we should on this account be disposed to reject the 
corresponding formula, and with it the axioms on which it depends. 

We do not know that any other remarks are called for by a review of the 
results of theory as contrasted with experiment. What, then, does the whole 
amount to? We find that there are three distinct ways of theorizing, each 
adopted, apparently, in accordance with the known laws of nature, but which 
differ essentially from each other. We do not perceive that our existing ex- 
periments bear with greater weight in establishing or in disproving any one 
of them than it does in establishing or disproving the other two. Each is 
confirmed by one experiment, each at variance with another. Are we to 
account for this circumstance from the difiiculty of conducting the requisite 
experiments, or are we not rather to attribute the anomaly to the little re- 
gard which has of late years been paid to a certain class of subjects, and 
especially to tlie one before us ? We are not aware that it has suggested itself 
to any one experimental philosopher to examine into the laws of conduction. 
Much labour, it is true, has been bestowed in examining the conductive pow- 
ers of different substances, and to the results of experiments carried on with 
this object we naturally look Avith the hope of extracting a law ; but, unfor- 
tunately, the nature of the experiments we are presented with is not such as 



24 REPORT — 1841. 

will lead to what we seek. They were not originally conducted with refer- 
ence to the state of things assumed to exist in theory, and are, in conse- 
quence, of less value when allowance is made for the difference between what 
they express and what theory requires. Now we do not deny that difficulties 
do attend the experimental examination of this subject, when it is intended 
to make everything correspond with the state supposed in theory. The 
chief and greatest of these we conceive to arise from the presence of the air. 
MM. Dulong and Petit have shown that the quantity of beat carried off by 
the air is not only very large, but is governed by a law very different from 
that of ordinary radiation. Means have therefore to be devised for removing 
this cause of error ; but we are far from thinking that the difficulty of effect- 
ing this amounts to an impossibility. If MM. Dulong and Petit could suc- 
ceed in determining the rates of cooling of a body hi vacuo, we cannot see 
why others should not succeed in observing the stationary temperature at one 
point, at least, of a body which radiates in vacuo. This leads us to the sug- 
gestions with which we shall conclude the present Report. We shall offer 
two: 1st, as to the most important experiments; 2ndly, as to the mode by 
which they may be conducted. 

It is perhaps chargeable against the theoretical writers on this branch of 
physics, and especially against M. Poisson, that they have not presented their 
results in a form sufficiently tangible to direct or suggest the application of 
experiment to them. It is much to be regretted that no attempt has been 
made to obviate this. With the view of remedying the state of things to a 
certain extent, we have exhibited in their most simple forms some of the 
more obvious conclusions to which the different theories lead. No doubt 
much might be done in this way, but, until called for by the entry of expe- 
rimenters on the field, a large and varied collection of formulae would serve 
no useful purpose. One class of experiments alone appears amply to suffice 
for our present purpose. The object being, to discover a law of conduction, 
it will be best attained by the selection of circumstances in which radiation 
either plays no part at all, or in which its effect is very simple and readily 
eliminated. The former condition exists in the problem which is solved by 
formulas 1, 15 and 16. By selecting a substance of small conducting power, 
such as marble, and coating the block with a substance which will radiate 
very slowly, this experiment may be made on a block of no very great di- 
mensions. For many reasons this experiment is well worth trying. It will 
probably distinguish at once between the three theories. It will certainly 
offer strong reasons for rejecting either the third or the fourth. Of course 
it will hardly serve to establish directly either of them. To effect this, we 
would point out another most important experiment, — The determination of 
tlie state of temperature at one extremity of a bar wJiich is heated at the other 
extremity. This experiment should be made on a variety of bars, of different 
conducting powers and of different lengths. With a set of careful experi- 
ments of this nature, we believe we could pronounce, without fear, the true 
law of conduction. Nor do we tliink the difficulties attendant on the con- 
duct of the experiments to be at all insuperable. The greatest obstacle is, 
no doubt, the expense of apparatus ; but where we find expense overruled in 
the prosecution of experimental researches into less important and certainly 
not more interesting branches of physics, Avhere theory has hardly opened a 
field for speculation, and where curiosity alone prompts the inquiry, it mus't 
excite our surprise that so little has been done in this case, which presents 
analytical developments of great beauty, and, independently of its close con- 
nexion with the favourite theories of light and the discoveries of chemistry, 
deserves to rank high amongst the physico-mathematical sciences. But, 



ON THE CONDUCTION OF HEAT. 25 

leaving expense out of the question, the real practical obstacle is the presence 
of the air. We have seen that the law of cooling into air is different from 
that of radiation. Even supposing, therefore, -we were in possession of the 
correct statement of that law, such would be the difficulty of obtaining for- 
mulae from it, that to attempt to eliminate its effect, together with that of 
radiation, is almost hopeless. If it can be done at all, it must be by means 
of experiments carried on in air of different elasticities. It has been proved 
by MM. Dulong and Petit, that " the velocity of cooling of a body due to 
the sole contact in a gas, depends, for the same excess of temperature, on the 
density and temperature of the gas ; but this dependence is such that the 
velocity of cooling remains the same if the density and the temperature of 
the gas change in such a way that the elasticity remains constant." The 
effect, then, of the presence of the air is to introduce a term which involves 
a power of the elasticity as one factor, and a function of the excess of tem- 
perature as another. The latter function may be determined (perhaps) by 
means of a number of experiments made at different elasticities. But we 
should greatly prefer a set of experiments on radiation in vacuo. It appears 
to us, that the difficulty in this case is very much the same as that against 
which MM. Dulong and Petit had to contend in investigating the kindred 
law of radiation ; and we should conceive that a similar contrivance to that 
which they used might be adopted to overcome it. All that we require is, 
that a certain portion of a bar heated at one extremity, radiate in vacuo, and 
that the temperature at two of its points, the other extremity being one, be 
capable of constant observation. MM. Dulong and Petit made use of a cop- 
per balloon which could be exhausted of air, and by means of ice be kept 
constantly to the freezing temperature, notwithstanding the radiation of the 
heat from the body within it. A somewhat similar contrivance we conceive 
would serve for the conduct of the experiment before us. The bar of metal 
to be experimented on migiit pass through the balloon and be heated in air, 
whilst the assumed point of heating might be marked by a thermometer in- 
serted into a hole in the bar just within the balloon. We wish M. Biot had 
marked his lowest point, not at the surface of the heated mercury, but at a 
point a little above it ; it would have insured greater steadiness in the re- 
sults. Should any one think of undertaking this experiment, we would 
recommend that he extend his observations over a wider range of tempera- 
tures than M. Biot has done. The thermometer which represents the heated 
end of the bar should stand permanently at every 5°, from 0° to as high as 
can be accomplished. It must be borne in mind, that two at least of the ob- 
servations are requisite for the determination of the constants, except in the 
case of formula li. The observations should likewise embrace a succession 
of bars of different substances, iron, brass, lead, etc., all of the same dimen- 
sions. Different series of observations should be made, in which the dimen- 
sions of the bars have different constant magnitudes, and others in which they 
have different lengths. All the substances might be coated with the same 
varnish, so as to render their radiating powers the same. With such experi- 
ments, we have no doubt that the law of conduction, although not like the 
law of radiation, an inference from direct observation, might be readily esta- 
blished, and the science of heat placed on the same footing with the other 
mathematical sciences. We hope that the Association, in making known the 
wants of this branch of philosophy, will induce some of the numerous distin- 
guished experimental philosophers whose names appear on their list, to take 

an interest in this matter. „ ,^ 

r. Kelland. 



26 REPORT — 1841. 

Report on Poisons. By G. L. Roupell, M.D., F.R.S. 

The complexity of the functions of the animal body, and their liability to 
disturbance from a number of causes, must be apparent to the most super- 
ficial observer. To those who endeavour to explain what takes place during 
the disturbed performance of the vital actions, many difficulties jjresent them- 
selves ; opposite causes occasion one common and similar result, and the 
same agent will produce very different effects under circumstances apparently 
analogous. Whilst, however, there may be thus many conflicting processes 
exhibited to us, we are satisfied that there are leading principles and general 
laws in operation which it is our great aim to seek for and discover. We 
cannot avoid allowing the proposition, " That under actually corresponding 
circumstances similar effects must ensue." Should then differences exist in 
the effects of any substance upon the system, as a poison for example, we 
naturally refer them to modifying influences ; at the same time that we explain 
the production of similar effects from opposite causes, by the agency of funda- 
mental principles, proving simplicity in the laws which regulate our frames. 

The object of my former communications has been to illustrate the effects 
of those poisons which induce an alteration in the vascularity of the different 
tissues with which they may come in contact, and to portray the appear- 
ances exhibited by dissection : on the present occasion some views will be 
stated concerning the operation of an agent which is constantly eliminated 
from the system, the effects of which, although not indicated by obvious local 
changes or capable of elucidation by drawings, appear nevertheless to be 
highly deserving of consideration and study. Carbonic acid is the agent 
alluded to ; one highly interesting, first, from its producing very marked and 
injurious consequences if applied in any way to the human body, either in- 
ternally or externally ; secondly, from its immediate connection with one 
highly important function of our system ; thirdly, from the analogy of its 
effects with some most serious maladies ; and fourthly, from the causes which 
influence its secretion. 

It cannot here be requisite to insist upon the necessity for the rejection of 
all effete matter from the body, or to show the importance of the changes per- 
petually going on in the circulating fluids. These points will readily be con- 
ceded to me ; nor will the mischief be questioned arising from the presence 
of certain principles in the blood, such as bile or urea ; but, while these sub- 
stances have deservedly occupied much attention of late, we are neglectful of 
an agent far more injurious. The ducts of the liver may be partially, if not 
entirely closed, for months ; the kidneys may be removed, or the secretion of 
urine may be suspended for more than a week, yet life during that time may 
be preserved ; but should the elimination of carbonic acid from the lungs be 
prevented for a few minutes, nay, only for a few seconds, life will be placed 
in imminent peril, if not irrevocably destroyed. 

We are well aware that carbonic acid is generated by various processes, 
for example, by decomposition, both of animal and vegetable bodies, by com- 
bustion, by fermentation, as well as by the respiratory apparatus. We are 
also aware that plants yield it by night ; that it is exhaled from tlie earth in 
certain situations, and that it is disengaged by chemical action, from com- 
pounds of which it forms an ingredient. We are certainly ready to admit 
that air charged with this gas, from whatever source it may be produced, is 
positively and highly detrimental. Sir Humphry Davy deemed it not beneath 
his notice to investigate the condition of the atmosphere rendered impure 
by persons crowding together in large or public assemblies, and showed that 
carbonic acid was present in excess in the vitiated air of such meetings. The 



ON POISONS. 27 

experiments of MM. Allen and Pepys, Lavoisier and Seguin, Davy and Ber- 
zelius, concerning the exact quantity of this gas evolved during respiration, still 
occupy the attention of the scientific world ; but its effects upon the system 
seem to me to be yet greatly overlooked and disregarded. The injurious 
consequences which it produces to those who, by accident or design, may be 
exposed to its effects, have led to less useful results, practically, than might 
have been anticipated from the nature of the symptoms, and the interesting 
phenomena which result from its action. Year after year numbers flock to 
witness the experiment of submitting a wretched animal to the deadly atmo- 
sphere of the " Grotto del Cane," without drawing those deductions, or de- 
riving that advantage from its sufferings, which alone can palliate or justify 
their infliction. 

Carbonic acid has many sources out of the body, and it is abundantly fur- 
nished by respiration. The lungs, however, are by no means its only outlet 
from the animal body. It is given off' by the skin, it is secreted as well by 
the serous as mucous membranes*, points of much interest, not only as afford- 
ing an example of vicarious action, but as explanatory of various bodily dis- 
orders. It cannot here be necessary to controvert old errors respecting the 
source of the carbonic acid yielded by respiration, nor to dwell upon the 
more probable views of modern times. The opinions and experiments of 
Mr. Edwards, which prove that this acid is extricated from the lungs, although 
no oxygen is respiredf , the observations of Professor Magnus, and his con- 
clusions that all blood contains carbonic acid, the belief of Miiller that the 
quantity held in solution in itij^ is sufficiently large to account for the whole 
exhaled by the lungs, are facts well known to all whom it is my pleasure to 
address. Thus we find that a most important series of changes takes place 
during the circulation of the blood leading to the formation of carbonic acid, 
which is set free from various surfaces, chiefly, however, from the parietes of 
the air-cells, which allow it to pass through them in order to be exhaled§. 
Next we find that many circumstances greatly influence the amount of this 
gas yielded by respiration ; these may be ranked in two classes, one of which 
may be considered as natural or regular, the other as accidental or abnor- 
mal. With regard to the first of these, to the regular performance of the 
functions of the system, we find that more carbonic acid is eliminated during 
the day than by night ; that it increases at day-break, and diminishes at sun- 
set II ; that it is produced in larger quantity by exercise and during digestion ; 
and, what is extremely interesting, we see a tendency to equilibrium in the 
whole amount ; for if given off in excess at one time, at another it wiU, as a 
consequence, be lessened. With regard to the second class of circumstances 
which influence the secretion, we find that it is diminished by depressing 
passions, debilitating causes, low diet, and injuries to the par vagumf . 

If we now look to the actual effects of carbonic acid, when placed in con- 
tact with the living body, many interesting consequences result which serve 
to indicate its use in the human economy, and its agency in disease. 

It imparts an acid taste, produces a sense of burning in the uvula**, and acts 
instantaneously as a powerful irritant to the muscles of the larynx, occasion- 
ing by their spasmodic action the complete and firm closure of the glottisff. 
Applied externally to the skin, or taken into the stomach, it occasions giddi- 
ness, pain and weight in the head, obscurity of sight, and ringing in the earstJ. 

* Mayo, Phys., pp. 120, 131. Mayo, Path., 336. Mullcr, Phys., 656. Robert Lee, Cy- 
clopscd. Pract. Med. vol. iv. p. 383. 

t Mavo, Phys., p. 63. t MUller, p. 328. § Miiller, p. 330. 

II Miiller, ibid. % Brodie, Phil. Trans., c. ii. p. 390. 

** Davy on Nit. Ox., p. 472. Christison on Poisons, 3rd ed., 745. ft Ibid. 

Jt Collaid de Martigni, Archives, 211. Christisou, 2ad ed., pp. 703-706. 



28 REPORT— 1841. 

Inhaled bj' tlie breath, it is well known to produce serious and alarming 
symptoms, varying as the gas may be more or less diluted. The following 
experiments show its effects when injected into the vessels. 

Experiment I. — To shotv the Effect of Carbonic Acid injected into the Veins. 

Two fluid ounces (by measure) of this gas, prepared by the action of di- 
luted hydrochloric acid upon chalk, were collected over water, and thrown 
slowly, by a syringe, into the external saphsena vein of a strong dog. Almost 
immediately afterwards the animal exhibited signs of uneasiness, uttered 
cries of distress, became convulsed, lost its consciousness, and appeared to be 
dying ; it felt, however, the stimulus of cold water when thrown upon it, and 
quickly recovered upon being removed into the fresh air. 

It thus is capable of producing a powerful impression on the system, when 
thrown into the veins even in a small quantity. Still more marked results 
ensued when it was introduced into an artery, as was shown in the next ex- 
periment. 

Experiment II. — To show the Effects of Carbonic Acid when thrown into 

the Carotid Artery. 

The left external carotid artery M^as exposed in the same dog, and a small 
tube was introduced into it, a ligature having previously been applied to 
prevent hemorrhage: a fluid ounce and a half (by measure) of carbonic acid 
was then thrown in. This was done gently, but it was necessary to discon- 
tinue the experiment, in consequence of the animal becoming convulsed and 
foaming at the mouth. After forty seconds it seemed to recover ; but again 
relapsed, lost all consciousness and power of movement, was quite insensible, 
and lay as if dead upon the floor. At intervals of a few minutes it was seized 
with attacks of violent spasms. This alternation of stupor and convulsions 
continued for four hours, when the animal regained its senses, the power of 
its limbs, and appeared afterwards to suffer no inconvenience. 

M. Nysten considers that the eff'ects witnessed on throwing carbonic acid 
into the vessels arise from the distension of the right side of the heart ; this 
seems, however, questionable in the experiment just detailed, as the gas was in- 
jected slowly in a direction from the heart, and produced other symptoms 
than those described as arising from the simple admixture of air with venous 
blood*. This eminent experimentalist certainly errs in considering that 
carbonic acid is not itself intrinsically poisonous. It cannot be necessary to 
pause in order to refute this idea, but it is worth while to mention the diver- 
sity in its effects : some speak of experiencing a lively sensation of pleasure 
on respiring it ; others, of the sensation of a gentle heat and perspiration ; 
and Sir Humphry Davy said he could answer, from his own experience, 
that no pain precedes the insensibility occasioned by breathing gases un- 
fitted for supporting life-j-. In general, however, vertigo, head-ache, accele- 
rated pulse, hurried breathing, palpitation of the heart, tendency to sleep, 
ending in complete loss of consciousness, with convulsions, mark its effects 
during life ; whilst retention of the warmth of the body, flexibility of the 
limbs, fluidity and blackness of the blood, characterise after death the bodies 
of those poisoned by this gas. 

If we now turn to those diseases, the leading symptoms of which bear resem- 
blance to the effects of carbonic acid, we find them to be such as prevent the 
proper arterialization of the blood, emphysema of the lungs, diseases of the 
heart; or, to be brief, all such as impede respiration, in which cases we find 
hebetude of mind, torpor of body, inclination to doze, spasmodic respiratory 

* Mayo, Phys., p. 72. t Salmonia, p. 112. 



ON POISONS. 29 

movements, and the tendency to convulsive muscular action. It is not, in 
truth, novel to refer these symptoms to the accumulation of carbon in the 
system ; but, close as the similarity in many respects undoubtedly is in these 
instances, the disorder in which we have the nearest resemblance, and which 
seems as if it were its true prototype, is still the Opprobrium Medicorum. 
We have in the symptoms produced by carbonic acid, the counterpart of those 
exhibited in epilepsy ; no less instantaneous is the attack of this appalling 
malady, than are the effects of the sudden closure of the glottis by the irri- 
tation of the choke damp, or other exposure to fixed air, by persons descend- 
ing into vats, or breathing the gas given off by fermentation. Plunge an 
animal into it, or inject it into the veins, and we can at will produce epilepsy 
with all its terrific features and depressing consequences. 

The curious coincidence of the diminished secretion of this acid from the 
lungs, towards evening, when the natural tendency to sleep comes on ; the 
increase in its quantity at day-break, when epileptic seizures are most likely 
to occur ; the hurried and spasmodic respiration, when it is present in excess, 
are valid arguments for the belief that it may be an active agent in exciting 
both healthy and disordered functions. 

Carbonic acid acts upon the medulla oblongata, for it annihilates volition and 
consciousness, which have their seat in this portion of the nervous centres. 
The medulla oblongata also, be it observed, is the source of the respiratory 
movements *. How these are called into action we are yet in doubt ; that 
they may be excited primarily and throughout life by the stimulus of car- 
bonic acid, is advanced as a conjecture, which derives abundant support from 
the analogy of other excretions. 

Minute details would here be out of place, or the quantity of this gas, 
capable of producing injurious consequences, and the peculiarities of indivi- 
duals rendering them especially liable to its influence, might be entered into. 
Suffice it, that extremely minute portions of gaseous bodies, as shown in the 
instance of the odour of musk, or the fragrance of flowers, is enough to pro- 
duce the most decided effects. 

It were tedious to enter into collateral inquiry, or to combat objections 
which may be advanced against the ideas thus submitted to the Association. 
It is doubtless extraordinary that an acid should be formed in the blood, and 
given off, instead of combining withthe alkali of the serum. The insensibi- 
lity of animals confined in nitrogen or hydrogen gases, in which the quantity 
of carbonic acid nearly equals that by natural respiration, may be otherwise 
explained ; new combinations may form ; carburetted hydrogen, for instance, 
may be generated, which would itself poison the animal ; and we should not 
forget the fact, that the insensibility, occasioned under the circumstances 
alluded to, is found to be much more easily dissipated than that which arises 
from the prevention of the escape of carbonic acid from the body. 

From this we might pass on to various spasmodic disorders, but it were 
perhaps premature to say anything further on this head ; only one more point 
shall be noticed in connection with this subject, and that is the resemblance 
in the effects of narcotic poisons to those arising from carbonic acid. Reflec- 
tions upon these facts have led me to think that tliis gas may play an essential 
part in the phenomena exhibited by narcotics, a class of substances, the 
operation of which is so little understood, but the action of which is ob- 
viously upon the functions of the system, rather than upon the vascularity of 
its organs. It has long been laid down as a rule, that opium is not to be ex- 
hibited when the blood is not i^roperly aerated or decarbonised. 

Many experiments have been made by me to ascertain whether any difference 
* MiUler, pp. 348, 351, 827, 918. 



so REPORT — 1841. 

existed in the quantity of carbonic acid given off from the system, when 
under the influence of opium. With this view the quantity eliminated before 
and after a dose of this drug had been taken, has been repeatedly measured. 
The experiments were performed by breathing through a solution of pure 
potassa, and by Aveighing the result, as well as extricating the carbonic acid 
acquired. It is unnecessary to enumerate the modifications in the apparatus 
used, in order completely to separate the watery vapour, to prevent the 
chloride of calcium employed for this purpose from descending into the 
potassa and negativing the result, to obviate the escape of minute portions 
of the solution of potassa on passing the expired air through it ; the conclu- 
sion arrived at is, that much more carbonic acid is given oif simultaneously 
with the production of the effects of opium. Not only is the number of re- 
spirations increased, and thus more is eliminated, but in an equal number of 
respirations there was found to be an increase of at least one-tenth. The 
quantity of opium. taken was equivalent to a grain and a half of the extract, 
and the observation was made as soon as the effects (tightness of the fore- 
head, slight sensation of nausea, accelerated pulse, quickened breathing, and 
general feehng of tranquillity) were perceived. It were easy to show the gene- 
ral likeness of the action of narcotics to those produced by carbonic acid gas ; 
but to connect them with this last-named agent will require further inquiry. 

Allow me now, in conclusion, to state that the ideas expressed in this paper, 
are submitted with great deference to the Meeting ; that they are advanced 
with the view of calling attention to certain interesting but obscure pheno- 
mena, and are forwarded in compliance with the desire of the Association. 

15 Welbeck Street, July 1841. 



Report on Discussions of Bristol Tides, performed by Mr. Bunt 
under the direction of the Rev. W. Whewell, F.R.S. 

[With Plates 2, 3, 4, 5.] 

The careful and intelligent manner in v/hich Mr. Bunt had conducted those 
Discussions of the Tides, on which the grants of the British Association in 
former years had enabled me to employ him, made me very desirous of continu- 
ing to profit by his labours, in order to bring, if possible, the ascertained laws 
of the tides nearer to the observations. With this view I applied at the last 
meeting for an additional grant of 50^. ; and have now to report the pro- 
gress which has been consequently made in our tide discussions. We began 
by considering the possibility of improving the correction for lunar declina- 
tion, and the determination of the anterior epoch of the semimenstrual in- 
equality. But it did not appear very probable that any additional discus- 
sion of the observations which we had before us would give us any additional 
accuracy, commensurate with the great labour which must be undergone in 
making the trial. I was therefore the more ready to follow out a suggestion 
of Mr. Bunt's, who wrote to me in January last that he had recently deter- 
mined to try whether he could perceive any effect on the heights of high 
water at Bristol produced by atmospheric pressure. He adds, " I accord- 
ingly arranged the errors of the calculated heights for 1840 in columns for 
every two-tenths of an inch of the barometer, observed contemporaneously 
with the tide." 

From a diagram given in his letter, the average effect appeared to be about 
15 inches depression of high water to 1 inch rise of mercury in barometer. The 
consistency of these results leaves no doubt as to the fact of a sensible effect on 
the heights from this cause. In his letter, he adds, " Some subsequent trials 



ON DISCUSSIONS OF BRISTOL TIDES. 81 

" gave nearly the same result, only a trifle less in the depression of high water 
" for an inch rise of mercury. The specific gravities of mercury and water 
" being not far (if I recollect right) from this ratio of 14 or 15 to 1, it would 
" seem that the total weight of the compound column of air and water raised 
" by the force which produces the tide, remains nearly unaifected by the 
" changes of atmospheric pressure. By introducing this new correction, there- 
" fore, a very considerable portion of our Residual Error is accounted for." 

The barometric observations which Mr. Bunt used for finding the effects 
of atmospheric pressure on the heights of high water at Bristol, were those 
contained in the register kept at the Bristol Institution, which extended back 
to a period earlier than the commencement of the tide observations. 

As it had appeared that all the other eff"ects of external forces upon the 
height and time of high water corresponded not to the forces at the moment 
of observation, but to a state of the forces at an anterior period, it occurred 
as possible that this might also be the case with the eff'ect of the atmospheric 
pressure upon the height of the tide ; and that the correction corresponding 
to this effect might be most accurately obtained by taking the state of the 
barometer at some period anterior to the time of high water ; for instance, 
twelve hours or twenty-four hours. If this were the case, we should be able to 
predict the effect of atmospheric pressure upon the tide, a day or half a day 
previous to the event. As this prospect gave an additional interest to the 
inquiry, I begged Mr. Bunt to try the comparative results of contempora- 
neous and anterior epochs of the barometric observation. This he proceeded 
to do, by arranging various portions of our observations according to the 
heights of the barometer. The following is the account of the result. 

"Bristol, Feb. 18, 1841, 

" I send you diagrams of the effects of atmospheric pressure on the heights 
of high water for every tenth of an inch height of the barometer, from 
29'2 or '3 inches to 30*4 or '5 inches, for the years 1834, 35, 39 ; barometer 
and tide contemporaneous. Also for the year 1834, barometer heights being 
twenty-four hours anterior to high water. Also for 1839, barometer 29*2, 
•3, '4, '5 inches to 30'2, '3, "45 inches, twelve hours anterior to high water. 
Also the mean of the three years, giving about 14 inches depression of tide 
to one inch rise of barometer. 

" I have also taken the sums of the'residues left after introducing the baro- 
meter correction, first, contemporaneously with high water, and secondly, 
at twenty-four hours anterior to high water, for the first six months of the 
year 1 834, measuring the residue at about every high water. The total re- 
sidues, in the two cases, were so nearly alike, as to leave it doubtful which 
epoch should be preferred. The diagram for 1834, made from observations 
of the barometer twenty-four hours anterior to high water, appears about as 
good as the one from contemporaneous observations of barometer and tide. 

The extreme groups, however, for 29*2, '3, "4 inches, 30*4, "5, '6 inches 

barometer, approximate slightly towards the mean line : the same tendency 

appears in the double groups 29*2, '3, "4, "5 inches, 30*2, '3, '4, "5 Inches, 

for 1839, barometer observed contemporaneously with, and at twelve hours 
anterior to, high water. Hence I should be disposed to infer, that we do not 
improve the result by going back to an anterior epoch ; for I take it for granted 
that the true epoch is that which shows the greatest amount of elevation and 
depression of tide corresponding with the least and greatest heights of the 
barometer ; or that which makes the greatest angle of inclination between 
the line connecting the several points or groups, and the axis. 

"There is one peculiarity which I have noticed in these barometrical results, 
and in others which I obtained in my earlier trials, namely, that the effect 



32 REPORT — 1841. 

produced on the heights when the barometei' is at any point below 29'4< 
inches or 29'5 inches, is always greater than the proportion for the greater 
heights of the barometer. I imagine this arises from the effect of wind, 
which generally follows a great depression of the barometer, and generally, 
with us, comes from the S.W. ; so that an additional elevating cause comes 
into operation. This, however, is mere conjecture." 

I then requested that, instead of arranging the observed heights according 
to the barometer, he would correct the observed heights for lunar and solar 
parallax and declination, and investigate the effect of atmospheric pressure 
on the residues ; still comparing the contemporaneous and the anterior epochs. 
The following was the result. 

"March 17, 1841. 

"I send you the results of comparisons of the residues of height for 1834, 
1835 and 1836, with the state of the barometer at different epochs. The 
heights Avere calculated carefully by numbers, using what I consider to be 
my best corrections for lunar and solar parallax and declination, and em- 
ploying the same corrections in each of the three years. The only correc- 
tion omitted was that for the diurnal inequality. The residues for 1834< 
were compared with the barometer contemporaneous, twelve hours anterior, 
twenty-four hours anterior, twenty-four hours posterior, and the extreme 
groups, with barometer, thirty-six hours anterior ; in order to find what pro- 
gressive changes of form the curves would thus be made to assume. The 
mean correction for one inch difference in height of barometer having been 
obtained, the proportional correction was applied to each observed height of 
high Avater, and the mean of all the errors (remaining after the barometrical 
correction) then taken for the whole year. In every instance the contempo- 
raneous barometer gives the best correction. Thus in 1834 the mean error 
remaining, after applying the barometrical correction, is 

5"817 inches contemporaneous barometer. 
6'085 inches barometer twelve hours anterior, 
6*221 inches barometer twenty-four hours anterior, 
6*248 inches barometer twenty-four hours posterior. 

"These two latter epochs, the one a7iterior the oihev posterior, producing 
nearly equal errors, seem to show (like equal altitudes) that the truth lies 
midway between them, 

" In like manner, the mean residual error for 1 835 is 

5'277 inches, barometer contemporaneous, 
5"421 inches, barometer twelve hours anterior, 
5*706 inches, barometer twenty-four hours anterior ; 

and for 1836 is 

6*450 inches, barometer contemporaneous, 

6*535 inches, barometer twenty-four hours anterior. 

" The introduction of the correction for the contemporaneous barometer re- 
duces the mean error, previously remaining, about one-fourth, being as 1 : 
0*753, for the whole of the year 1834 ; and as 1 : 0*705 for the year 1835. 

" The mean effect on the tide corresponding to a change of one inch in the 
mercurial column was carefully obtained, by taking into account the number 
of observations in each parcel, so as to get the true average. The con- 
temporaneous barometer gives, in every instance (as shown in the diagrams), 
the greatest result : and in this case also equal differences from the maximum 
attend the anterior and posterior epochs for 1834 — viz. 11 inches tide (instead 
of 13*4 inches) to one inch of mercury. 



I 



ON THE DISCUSSION OF LEITH TIDE OBSERVATIONS. 33 

" The mean depression of tide corresponding to 1 inch rise of barometer, is 

inches. 

For 1834 13"4 (contemporaneous barometer), 

1835 14-6 ( ditto ditto ), 

1836 11-9 ( ditto ditto ). 

Mean. ... 13'3 for three years." 

Thus this last investigation appears to have put a negative upon the 
supposition that the barometric correction of the height of high water cor- 
responds to an anterior epoch ; for we cannot doubt the justice of the re- 
mark made by Mr. Bunt, that since not only the contemporaneous barometer 
gives the greatest result, but since also equal differences from the maximum 
attend the epochs anterior and posterior by twenty-four hours, the contem- 
poraneous epoch must be the true one. And thus it appears that the effect 
of atmospheric pressure on the height of the tide is something local and im- 
mediate, not an effect transmitted in a finite time from some other place. 

I next wished Mr. Bunt to try how far the correction curves of height for 
lunar and solar parallax and declination would have been different if the 
barometric correction had been m&die first, before the heights were arranged 
for the other corrections. This also he undertook. The following is his 
communication on the subject. 

"April, 1841. 

"I send you new correction curves made from the observed heights in 1839, 
after haw'mg first cleared them of the effects of the changes of atmospheric 
pressure, allowing 13^ inches of water to one inch difference in the barome- 
tric column. The greatest difference is in the solar declination curve at the 
hour 65 of transit. I hardly think this can be entirely owing to the atmo- 
spheric correction, but most likely to some difference in the working out of 
the new lunar corrections, especially that for declinations, with which the 
solar declination is almost inseparably mixed up in any short series of obser- 
vations. Indeed I can scarcely see how the effects of the two kinds of decli- 
nation can be separated, with any certainty, about the hours of 0'' and Q^ 
transit, except by taking two sets of observations, the one having the moon's 
declination a maximum, and the other a minimum." 

The very small differences between these correction curves in their former 
shape, and as modified by allowing for the barometric correction, might have 
been expected, since the barometric correction will, on the whole, compen- 
sate itself. The smallness of the differences is, however, evidence of the 
care and consistency with which our results were formerly obtained. 

W. Whewell. 
Trinity CoUege, Cambridge, July 1, 1841, 



Report on the Discussion of Leith Tide Observations, executed by Mr. 
D. Ross, of the Hydrographer's Office, Admiralty, under the direc- 
tion of the Rev. W. Whewell. 

Although tables of the corrections of the heights and time of high water, 
due to lunar parallax and declination, have already been obtained for several 
places, (London, Liverpool, Plymouth, and Bristol) it is still desirable to cor- 
rect and confirm these results by the discussion of observations made at other 
places, especially if continued for a considerable series of years. Our methods 
of discussion and tabulation may admit of improvement, and new features 
may appear in the new results ; with these views I applied at the last meeting 
1811. D 



34 REPORT — 1841. 

of the Association for the sum of 50/. to enable Mr. Ross to complete the 
discussion of a series of tide observations made at Leith, extending from 1827 
to 1839 inclusive, and now including 184'0. This long series of years is ad- 
vantageous for the purpose of obtaining the declination correction ; since, in 
consequence of the motion of the moon's nodes, the range of lunar declina- 
tion and the mean declination is verj- different in different years ; as was 
stated in my Report on the subject, presented to the Association last year. 

The present Report will i-efer to a new mode of presenting the corrections 
of the height of high water for lunar parallax and declination. It has been 
shown by me in various memoirs that the correction of the height both for 
lunar parallax and declination is nearly the same for all the hours of moon's 
transit. This being the case, the greater part of this correction may be ex- 
pressed by means of a table of double entry ; the two arguments being the 
moon's parallax and declination. Mr. Ross suggested to me the advantage 
of such a table, and has constructed it from the Leith observations, and it is 
laid before the Association along with the present Report. 

It appears by this table, when separated into the two parts dependent upon 
parallax and declination, that the parallax correction varies very exactly as the 
parallax; and that the declination correction applicable to declination , varies 
very nearly as the square of the declination ; results agreeing both with those 
obtained from the tide observations made at other places, and with the conse- 
quences of the equilibrium theory modified, as I have previously shown that it 
must be, in order to express the results of observation. As I have stated, the 
principal part of the correction of the height of high water for lunar parallax 
is constant for all hours of moon's transit. But there is a further term of this 
correction, though a small one, which goes through a cycle of positive and 
negative values in the course of a semilunation. This has already appeared 
in the results of the London, Liverpool, Plymouth, and Bristol observations, 
and also agrees with the theory above referred to. A like result appears in 
the results of Leith tides by the discussions now reported, but at first sight 
with a remarkable difference. At Plymouth it appeared (Ninth Series of Tide 
Researches, Phil. Trans. 1838), that the correction for parallax is least when 
the hour of moon's transit is 10*^, and greatest when the hour of moon's 
transit is 4^ or 5*^ ; the mean parallax correction when the part depending on 
the hour of transit disappears, occurs at transit l"* and 1'^. At Leith, on the 
contrary, the effect of the parallax is greatest when the transit is about 6"^, 
least when the transit is 0^ and the mean value obtains when the transit is 
about 3"^ and 9**. But this great difference in the results, which at first ap- 
pears to make the course of this correction nearly opposite at the different 
places, is, in fact, the result of the difference of the time which the original 
tide-wave employs in reaching Plymouth and Leith. This correction varies 
nearly as the sine of the double angle of the moon from the sun, minus a 
certain epoch. Or to be more exact, instead of the sine we may substitute a 
circular function, which vanishes, and is positive and negative when the sine 
is, but which does not exactly follow the law of the sine. If this function be 
called s, the term of which we are now speaking is, in the Plymouth tables, 
as 5, 2 — 14" ; in the Leith tables it is as s, 2 — IS**. The difference of 
the epochs, \\^ and 18'', depends on the time of transmission of the tide 
from Plymouth to Leith. This is further illustrated by remarking that in 
the results of London observations this term is also represented by *, 2 — IS*" ; 
while the Bristol observations give the term s, 2</) — 15*^. 

The agreement of these results cannot but be considered as decisive evi- 
dence of the correctness of the tables which M'e have obtained, as to their 
form and general law. And this is the more remarkable when we consider 



ON THE DISCUSSION OF LEITH TIDE OBSERVATIONS. 



35 



how small are the results in which this coincidence is found. The coefficient 
of the term now spoken of, is at Loudon 3 inches ; at Plymouth it is 1 inch ; 
at Bristol, when the rise and fall is very great, this coefficient is 6 inches ; 
at Leith, by the present discussion, its amount is found to be little more than 
1 inch. The smallness of this term also leads us to this inference, that 
Mr. Ross's table of double entry may be used to obtain the corrections of 
heights for parallax and declination, almost without a sensible error. The 
table being obtained from Leith observations, will require a constant multi- 
plier to adapt it to other places. 

TABLES. 

(1.) Mr. Ross's table of the correction of height for parallax and declina- 
tion. 

(2.) Mr. Ross's table of the difference of the parallax correction from the 
mean for each hour of transit. 

^3.) The mean value of this difference for each hour of transit. 

(4.) The mean value of this difference for each 3° of declination showing 
that the declination correction is nearly as the square of the declination. 

(5.) The semimenstrual inequality of height for Leith. 



Declination 
Moon's. 


544. 


551. 


561. 


57i. 


581. 


59i. 


601. 


611. 




(4.) 


o o 




in. 




in. 


in. 


in. 


in. 


in. 


in. 




in. 


in. 

+ 4-2 
+ 4-5 


0-3 


— 


5-2 


— 


1-6 


+ 2-3 


+ 6-4 


-I-8-7 


+ 11-4 


+ 17-5|+ 


19-3 




3-6 


— 


5-6 


— 


1-5 


+ 2-7 


+ 8-8 


+ 9-7 


+ 12-2 


+ 16-4 + 


20-4 




1 *^ " 

+ 3-6 


6- 9 


— 


6-4 


— 


1-7 


+ 1-4 


+ 5-1 


+ 9-5 


+ 12-3 


+ 15-0|+ 


19-1 




4-2-5 


9-12 


— 


6-7 


— 


3-2 


+ 0-5 


+ 4-1 


+ 8-4 


+ 11-0 


+ 14-8 


+ 


16-3 




1 

+ 1-3 
- 0-9 


12 - 15 


_ 


7-6 


— 


4-0 


-0-8 


+ 3-0 


+ 6-4 


+ 10-2 


+ 12-4 


+ 


16-3 




15 - 18 


— 


9-2 


— 


6-2 


-3-8 


-0-3 


+ 4-1 


+ 7-8 


+ 11-2 


+ 


14-3 




-2-7 


18 -21 


— 


110 


— 


9-0 


-3-4 


- 1-3 


+ 3-4 


+ 5-8 


+ 9-1 


+ 


10-5 




-2-9 


21 -24 





11-5 


— 


8-8 


-5-7 


-0-6 


+ 2-1 


+ 7-2 


+ 10-1 


+ 


90 




- 4-4 


24 -27 


_ 


12-3 


_ 


101 


-6-0 


— 2-2 


-1-0-3 


+ 4-7 


+ 8-7 


+ 


7-0 




- 6-0 


27 -29 


— 


150 


— 


12-4 


-8-6 


-4-8 


+ 0-7 


+ 2-3 


+ 6-4 


+ 


8-4 






(3.) 








(2.) 




0-30 





1-7 





20 


- 1-2 


-0-4 


-2-9 


+ 0-4 





+ 


0-5 


- 1-6 


1 -30 





11 





0-5 


-22 


- 2-1 


- 1-0 


- 1-0 


- 0-4 




1-9 




- 1-3 


2-30 


+ 


0-3 


— 


0-7 


- 1-6 


- 11 





- 0-7 


+ 0-5 








-0-6 


3-30 


+ 


10 


+ 


11 


+ 0-1 


-0-2 


- 1-2 


- 0-6 


+ 0-9 








+ 0-2 


4-30 


+ 


11 


+ 


1-3 


+ 0-9 


+ 0-9 


4-0-6 


+ 0-3 










+ 1-0 


5 -30 


+ 


11 


+ 


1-5 


+ 1-0 


+ 1-8 


+ 0-8 


+ 0-2 










+ 1-2 


ti -30 


+ 


0-8 


+ 


1-8 


+ 1-9 


+ M 


+ 1-3 


+ 0-3 










+ 1-4 


7-30 


+ 


1-3 


+ 


11 


+ 0-4 


-0-2 


+ 0-6 


+ 0-9 










+ 0-6 


8-30 


-t- 


0-2 


-h 


0-3 





+ 0-6 


-0-6 


- 0-2 


- 1-7 








+ 0-1 


9-30 




0-3 




0-8 


+ 01 


+ 0-1 





+ 0-1 


- 0-3 








-0-2 


10-30 





0-9 





1-8 


-0-7 


I 1-5 


+ 0-2 


1 0-2 


- 0-8 









-0-9 


11 -30 


— 


1-8 


— 


2-5 


-0-4 


- 11 


I 0-8 


+ 0-1 


- 0-5 


+ 


0-5 




- 1-3 



b2 



36 



REPORT — 1841. 

















( 


[5.) 


Semimenstrual L 


ines. 


















0-30 


1- 


30 


2-30 3-30 


4-30 


5- 


30 


6-30 


7-30 


8-30 


9-30 


10-30 


11-30 


1827 


16 


2 


15 


6jll4 


8J|13 


m 


13 


24 


12 


94 


12 llf 


13 


104 


14 


9 


15 


64 


16 


04 


16 3 


1828 


16 


4*15 


11 


15 


OJlU 


n 


13 


5 


12 


114 


13 14 


14 


1 


15 





15 


9f 


16 


5 


16 74 


1829 


16 


3ijl5 


11 


14 


llf 14 


2 


13 


n 


12 


94 


13 14 


13 


11 


14 


9f 


15 


H 


16 


n 


16 5i 


1830 


16 


3J 


15 


8J14 


lOi 


14 


Of 


13 


14 


12 


n 


13 14 


13 


101 


14 


94 


15 


7t 


16 


n 


16 54 


1831 


IG 


5| 


15 


9| 


15 


Of 


14 


2| 


13 


4 


12 


114 


13 1 


13 


m 


14 


9" 


15 


8* 


16 


4 


16 64 


1832 


16 


H 


15 


8J 


14 


10 


13 


11 


13 


H 


12 


9 


12 lU 


13 


9f 


14 


71 


15 


5 


16 


Oi 


16 3^ 


1833 


15 


llf 


15 


7-J 


14 


9^ 


13 


11 


13 


IJ 


12 


9^13 


13 


9f 


14 


8f 


15 


5| 


15 


llf 


16 2 


1834 


16 


1 


15 


7 


14 


10J!14 


01 


13 


1 


12 


74112 10| 


13 


»i 


14 


8 


15 


6 


16 





16 34 


1835 


16 


Oi 


15 


H 


14 


8f|13 


94 


12 


IH 


12 


6;|12 lOA 


13 


8i 


14 


84 


15 


7i 


16 


1* 


16 2| 


1836 


15 


lOf 


15 


4 


14 


7iil3 


10 


13 


oj 


12 


5i 


12 11 


13 


8^ 


14 


6i 


15 


4| 


16 





16 If 


1837 


15 


9i 


15 


3 


14 


5*13 


n 


12 


84 


12 


24 


12 7 


13 


44 


14 


6 


15 


34 


15 


10 


16 1 


1838 


15 


8J 


15 


2| 


14 


6^,13 


64 


12 


8f 


2 


12 5J 


13 


24 


14 


3i 


15 


3i 


15 


94 


15 104 


1839 


15 


7-i 


15 


2 


14 


4il3 


7i 


12 


7 


12 


24 


12 5| 


13 


44 


14 


3 


15 


Of 


15 


84 


15 104 


1840 


15 


H 


15 


4 


14 


7H3 


84 


12 


n 


12 


54 


12 8i 


13 


4 


14 


4 


15 


2 


15 


81 


15 lOi 



Upon the ivorking of WhewelVs Anemometer at Plymouth during the 
past year. By W. S. Harris, Esq., F.R.S. 

My last Report on this instrument contained an account of cei'tain im- 
provements in the mechanism and mode of fixing found by experience neces- 
sary to its perfect employment. I have now the satisfaction of bringing under 
the notice of the Physical Section a series of observations, continued for a 
whole year ; from which has been laid down, by the inventor's method, a gra- 
phic delineation or type of the wind during this time, and extending from 
July 184'0 to July 1841*. It will be seen by this chart now before us, that 
we have, to a great extent, realized Mr. Whewell's happy thought, namely, 
that of obtaining a sort of type of the winds for a given place, so as eventu- 
ally to arrive at the general annual movement of the air. The mean result 
of the observations now before us agrees nearly with that arrived at by the 
observations made by Mr. Southwood, with the same instrument, and printed 
in the Eighth Report of the Association. It shows in this place (Plymouth) 
an annual movement of the air from the S.S.E. toward the N.N.W. nearly. 
It is not a little interesting to observe the daily march of the wind, as indi- 
cated by the daily register of the instrument. We find, for example, certain 
tourbillons or great disturbances occurring here and there, which seem to 
interfere with what might probably, in more settled latitudes, be a constant 
and regular movement of the air, as in the trade winds ; yet, upon the whole, 
the progress of such a regular current is traceable, notwithstanding these in- 
terferences ; and the movement of the air is found to be by this chart from the 
southerly to the northerly points of the compass. It does not seem requisite, 
for our present purpose, to attempt more than a very summary generaliza- 
tion ; without therefore obtaining, by a strictly geometrical method, the re- 
sultant magnitude and direction for each month, and from these again the 
resultant magnitude and direction of the Avhole, as done in my former Report, 
it will perhaps suffice to pass a line immediately through the whole series of 
types, in such way as to obtain by the eye alone the final resultant. Such a 
line will evidently pass from the S.S.E. to the N.N.W. points of the compass, 
or very nearly. If now we associate this fact with the result obtained from 

* The delineation liere referred to was exhibited in the Section-room, in a frame 12 feet 
high by 6 feet wide. 



UPON THE WORKING OF WHEWELL's ANEMOMETER. 



37 



the hourly meteorological observations at the Dockyard, we are entitled to 
say, so far as our experiments extend, that there is an annual movement of 
the atmosphere in this latitude toward the north, under a mean pressure of 
29*900 inches nearly, taken at the level of the sea, and a mean temperature of 
52° Fahr. The complete and satisfactory working of the anemometer, now 
that it has undergone certain amendments, found by experience desirable, leads 
me to hope that its use will be persevered in by observers in meteorology, since 
the principle on which it has been founded is undoubtedly very perfect and 
satisfactory. I do not, after a very critical examination, and experience in the 
use of the instrument, see any difficulty whatever in respect to its mechanism 
which may not be easily conquered ; and it only now remains to find what 
are the actual numerical values of its indications ; that is to say, having been 
enabled to trace an annual movement of the air in the direction above stated, 
we should at the same time be enabled to determine the rate of the motion. 
This would seem at first sight a sufficiently difficult matter. We may hope, 
however, to arrive at something like a fair approximation to such information, 
by the following mode of experiment, now in progress. 

With a view of determining the amount of pressure as observable by ex- 
posing surfaces varying in dimensions to the aerial current, the poi'table gauge 

I represented in the annexed figure has been suc- 
cessfully applied. A brass quadrant d e, being 
set in a frame of brass and divided in the usual 
way, a pressure plate a is so applied on the top 
of the frame as to act by a rod h I, and a silk 
line over intervening pulleys on the spiral spring 
6; the pulley c fixed in the centre of the quadrant 
carries the index cf, which will rise on the gra- 
duated arc in proportion to the pressure, the 
amount of this pressure in terms of a standard 
of weight being known by experiment, that is, 
by placing different weights on the extremity of 
the rod held in a vertical position, and observing 
the corresponding degrees on the arc. If Lind's 
gauge be employed as a standard, we may readily 
examine the pressures corresponding to various pressure plates, and thus dis- 
cover whether the same pressure on a unit of area is shown by different sized 
plates. This being determined, we are in a state to employ plates of different 
dimensions according to the violence of the wind, and hence readily compare 
the pressure with the velocity more easily. 

To find the velocity by experiment, a cork stuck round with capacious 
feathers is made to travel over a fine wire of a given length by the force of 
the wind ; the cork is set on a common writing quill bushed with a small brass 
plate at each end, and by which the whole is supported on the wire, fine holes 
being drilled through tlie brass plates for receiving it. This contrivance 
is extremely light, and will fly along the wire with the velocity of the wind 
for a given distance, or very nearly so. It is in fact throwing, as it were, a 
log-line upon the air. Observers may now compare the pressures, correspond- 
ing to certain velocities, and to the descent of the pencil on the anemometer ; 
and thus its indications are reducible by experiment to terms of absolute value, 
when a sufficient number of observations have been made and tabulated. 




38 REPORT — 1841. 

Report of a Committee, consisting of Sir J.W.F. HERSCHEL,J5«r^., ikfr. 
WHEWEhL.fthe Very Rev. theDE AN OF^i.\, Prof hijOYD, and Lieut. - 
Col. Sabine, appointed for the purpose of superintending the scien- 
tific co-operation of the British Association in the system of Simul- 
taneous Observations in Terrestrial Magnetism and Meteorology. 

Your Committee, referring to their last Report for the history of the mag- 
netic operations in progress up to the date of that Report, have to state, in 
continuation, that the magnetic observatory at St. Helena was finished, and 
the instruments established, in August 184-0, — at Toronto in September, — 
and at Van Diemen's Land in October of the same year. The observatory at 
the Cape of Good Hope also was completed and in activity at the commence- 
ment of March in the current year, delays having occurred in its completion, 
which, though productive of great uneasiness and distress to its officer in 
superintendence, Lieut. Eardley Wilmot, could in no way be attributed to 
any want of exertion, or to any negligence on his part. From each of these 
stations returns have been regularly received since their respective dates of 
completion. Previous to this, there have been received returns of seven 
months of observation in a temporary observatory at Toronto, and of six at 
St. Helena. All the observations, as soon as received, have been regularly 
transmitted to Prof. Lloyd, and after examination by him, handed over to 
Col. Sabine, under whose superintendence, assisted by Lieut. Riddell — the 
state of whose health, unfortunately, has compelled his return from Toronto 
— their publication will take place. Government having, on the application of 
the Royal Society, taken upon themselves this additional expense. In conse- 
quence of this arrangement, the reduction and printing of the observations 
are now in progress. The portable observatories of the Erebus and Terror 
were put up at Kerguelen's Land, and also at Van Diemen's Land. At the 
former station, the May and June terms were observed — at the latter, those 
of August and September 1840. During the stay of the expedition at these 
stations, the magnetometers were observed hourly ; and the regular work of 
the observatory at the latter station, under the direction of Lieut. Kay, has 
been begun, and will be continued on this doubly-laborious plan of hourly 
intervals for the ordinary observations ; while on the term-daj's, all the three 
magnetometers will be observed at the same instants of time, at intervals of 
2^ minutes, — the means of confronting this vast increase of labour being sup- 
plied by the Colonial Government, as administered by that ever-active and 
zealous friend of science, Sir J. Franklin. And in addition to this, and for 
the sake of multiplying occasions of observing the correspondence of magnetic 
perturbations with auroral discharges, one hour out of every 24 — viz. from 
Ih. 50m. P.M. to 2h. 50m. p.m., Gottingen mean time, commencing from 
January 1, 1841 — will be occupied with observations of the magnetometers, 
at 2\ minutes' interval, in this order, viz. bifilar, declination ; vertical force, 
declination ; bifilar, declination, V, D, B, D, &c. It is to be hoped that 
some of the European observatories will, at least occasionally, furnish obser- 
vations in correspondence with these. 

The reduction and publication of the observations made at the Van 
Diemen's Land observatory and by Captain Ross's expedition have also, at 
the request of the Admiralty and with the consent of the Master General of 
the Ordnance, been placed under the superintendence of Lieut.- Colonel 
Sabine. 

The first Report of the Director of the Madras Observatory (Lieut. Lud- 
low), and the first month's observations, have been received. It commenced 
regular observation on the 1st of January 1841. 



ON TERRESTRIAL MAGNETISM AND METEOROLOGY. 39 

The private observatory established at Mukerston in Scotland, by the mu- 
nificence of Lieut.-General Sir Thomas Macdougal Brisbane, has been com- 
pleted in instruments, and has commenced observation. In addition to the 
terms, a portion of the usual daily routine of magnetical and meteorological 
observations will be kept up at this observatory. 

Of the foreign European observatories, Brussels (M. Quetelet), Prague 
(Herr Kreil), and Milan (Sig. Carlini), have regularly forwarded the term- 
observations for each month to the Royal Society. The Cadiz observatory 
has been completed in instruments, and its director, M. Montojo, has person- 
ally visited Dublin, to receive Prof. Lloyd's instructions in the process of ob- 
sei-vation. In consequence of an application made to the Belgian Govern- 
ment by the Royal Society, through Lord Palmerston, the establishment of the 
Brussels observatory has been provided with the assistance necessary to carry 
out the complete system of observation recommended by the Royal Society. 

From Breslau a letter has been received from M. Boguslawski, dated 
July 3, giving an account of the progress of that establishment, the instru- 
ments for which, it will be recollected, were supplied by this Association. 
Annexed to this letter are the projected term-observations for August and 
November 1840. It will be necessary to provide expressly for the final dis- 
posal of the returns which will arrive from this quarter. 

The Council of the Royal Society had devoted a sum of money from their 
Wollaston Donation Fund for the purchase of a set of instruments for the 
magnetic observatory, the erection of which at Alton, near Hammerfest, was, 
at the date of the last Report of this Committee, under consideration by the 
Norwegian Government. Some difficulties have presented themselves since, 
which will probably prevent, or materially modify, the accomplishment of 
this object, or substitute for observations at Hammerfest a series to be made 
at Christiania, under the direction of M. Hansteen. Be this as it may, this 
liberality on the part of the Royal Society was highly opportune, inasmuch 
as it left disposable the grant placed at the disposal of your Committee at the 
last meeting. 

Under the head of " Observatories entirely new," your Committee have to 
announce the projected establishment of a private one at Havaiiah, by Drs. 
Belot and Jorg, which from the geographical position of the station will be 
extremely valuable. 

The term-days of May and August 1840 have been both remarkable for 
the magnitude of the disturbances. Mr. Riddell has undertaken to have all 
the observations of these two days projected in curves, which will probably 
be completed and laid before the Association at this meeting. 

By a letter received from M. KupfFer, dated 25th March 1841, it appears 
thatthe observations in the magnetic observatory at St. Petersburgh com- 
menced on the 1st of January, and at Caterinenbourg on the 10th of March. 
In the course of the summer they will be commenced at Helsingfors ; and at 
Tiflis, in all probability, during the autumn. The total number of magnetical 
observatories which may at present be reckoned on as brought, or about to 
be brought, into effective co-operation, is fifty-one. 

On the 12th of November 1840, the Erehis and Terror left Hobart Town 
for their first summer's research in the Antarctic Circle, leaving Lieut. Kay, 
with Messrs. Dayman and Scott as his assistants, in charge of the ob- 
servatory at Ross Bank. During the temporary sojourns of the expedition 
on land or ice, the observations will be made on the same enlarged plan as at 
Hobart Town. Their first term will, in all probability, have been observed 
in November at the Auckland Islands. The first point to be determined 
would be, the point of maximum intensity in the southern hemisphere, the 



40 REPORT — 1841. 

meridian of which had been indicated by the daily observations in the pass- 
age from Kerguelen's Land to Van Diemen's Land, leaving only its latitude 
undecided. Having accomplished this, they will proceed, as rapidly as cir- 
cumstances will permit, to seek and determine the position of the point of 
vertical dip. The observations at sea, it should be mentioned, succeed to the 
fullest extent of the most sanguine expectations ; so much so, that the three 
magnetic elements are daily observed on board, with a precision perfectly 
adequate to the actual demands of magnetic science. 

Intimately connected with a system of simultaneous observations at central 
stations, is the subject of magnetic surveys of the surrounding districts. It 
is only by reference to such central stations as zero points, that itinerant de- 
terminations can be divested of the influence of temporary and casual mag- 
netic derangement, and brought into comparability with the general mag- 
netic system of the globe. It is, therefore, of the utmost importance that 
every advantage should be taken of the present fortunate conjuncture to secure 
the ivhole benefit of the simultaneous system, and to extend it from points 
over districts. Itinerant observations, made on a concerted system, and pre- 
cisely simultaneous with those at the fixed observatories, will acquire (if accu- 
rately made) all the value of stationary ones, becoming, ipso facto, and at 
each instant, reducible to a central station. Moreover, by this means alone 
can the amount of station-error for each element, at the central stations them- 
selves, be ascertained ; by which is meant, all that part of each resolved ele- 
ment of the magnetic force, which, not being participated in by the surround- 
ing district, must be attributed to attractions merely local and accidental. 
Without such surveys, executed at some epoch, this error cannot be even 
approximately fixed. If executed at this particular time, not only will it be 
settled with precision, but the surveys will become an integrant part of 
the whole mass of observation, and be rendered infinitely more valuable as 
data for future reference, than they could possibly be, if deferred till after 
the conclusion of the stationary observations. 

Under this impression, it is highly gratifying to your Committee to be en- 
abled to announce, that one very important survey of this kind — that of the 
British possessions in North America — has, on the application of the Presi- 
dent and Council of the Royal Society, been undertaken by Government, on 
a scale both liberal and satisfactory — a young, ardent, and instructed officer, 
Lieut. Younghusband, R.A., qualified for the work by a residence and prac- 
tice in magnetic observation in the observatory at Toronto, having been added 
to the establishment of that observatory, with a view to this especial ser- 
vice, for three years, with a non-commissioned officer as his assistant, fur- 
nished with every instrumental requisite, a liberal provision for travelling 
expenses, and with the promise of gratuitous canoe conveyance, from the 
Hudson's Bay Company, in the territories belonging to them. In anticipa- 
tion, moreover, of a similar magnetic survey of South Africa, though as yet 
no formal application for such a survey has been made, the Master-Gene- 
ral of the Ordnance has ordered a second officer of Artillery (Lieut. Clerk) 
to be attached to the observatory at the Cape of Good Hope. 

As regards this important department of the general subject, your Com- 
mittee have further to notice the magnetic survey of British Guiana, which 
has been undertaken by Mr. Schomburgk, one of the Commissioners appointed 
by Government to determine the boundaries of that province, and who, on an 
application to that effect on the part of the Royal Geographical Society, has 
been supplied by your Committee, from the grants placed at their disposal, 
with a transportable magnetometer (to be returned when the Avork is com- 
plete) — the receipt of which is acknowledged by a letter from the Secretary 



ON TERRESTRIAL MAGNETISM AND METEOROLOGY. 41 

of that body, dated Feb. 10, IS^l. Nor must your Committee pass in silence 
the instructions given, and the instruments supplied by Government, (in du- 
plicate, and with complete instructions for the use of each,) — also on applica- 
tion from the President and Council of the Royal Society, — to the African 
Expedition, for the purpose of observation in the course of that expedition. 
From the scientific zeal which distinguishes many of the officers of that ex- 
pedition, — scarcely inferior to that zeal in the cause of humanity which has 
led them to enter on so perilous a service, — results highly valuable to mag- 
netic science may be expected. The transportable magnetometer being one 
of their instruments, observations on term-days during some months, corre- 
sponding with those in Guiana, will probably be obtained, and thus localities, 
otherwise of high interest, and remote from any central station, will be bound 
together. 

Mr. Caldecott, Astronomer to His Highness the Rajah of Travancore, 
whose magnetical observatorj^, completely furnished in instruments, com- 
menced its operations on the May term-day of the present year, has also de- 
clared his intention to undertake the magnetic survey of Southern India; 
while in the north of that empire we may expect, from the zeal and energy 
of Capt. Boileau, that no exertions on his part will be wanting to secure a 
similar advantage in that quarter. 

In all such surveys it is highly desirable that a regular and concerted sy- 
stem of observation should be followed, and above all things, that the con- 
dition of exact conformity to the hours of simultaneous observation should 
be adhered to ; as well as that, if practicable, all determinations of important 
points, intended to be made with particular care and exactness, should be 
performed on the term-days ; which object, by the exercise of a certain de- 
gree of forethought in laying out the plan of travel, may doubtless be accom- 
plished in the great majority of instances. 

Connected with, and of importance to, the practical working of the obser- 
vatories, your Committee beg leave to call attention to Prof. Lloyd's supple- 
mentary paper, " On the Mutual Action of permanent Magnets," in which 
those conditions of equilibrium are investigated which it is possible to satisfy, 
independent of the relative forces of the magnets. In this paper, independent 
of the practical utility of the rules laid down for the disposal of the magnets 
in fixed observatories, the demonstration of the extreme minuteness of the 
possible amount of uncompensated error arising from mutual attraction can- 
not but be regarded as highly satisfactory. 

Finally, your Committee have to report on their employment of the grant 
of 50/., placed at their disposal at the last meeting, which they have expended 
on the purchase of a transportable magnetometer, by Meyerstein, of Gottin- 
gen, for the Guiana survey. Some improvements, not contemplated origin- 
ally, having been introduced into the construction of this instrument, its total 
cost, including freight, somewhat exceeded this sum, leaving a balance of 
121. 2s. against the Committee, for which it is necessary they should pray an 
indemnity, as well as a continuance of the grant of money placed at their 
disposal. Signed, on the part of the Committee, 

J. F. W. Herschel. 



Reports of Committees appointed to provide Meteorological Instru- 
ments for the use of M. Agassiz and Mr. M'Cord. 

With reference to the resolutions passed at Glasgow, viz. " That a Com- 
mittee, consisting of Major Sabine and Sir J. Herschel, be requested to pro- 



49 REPORT — 1841. 

vide two actinometers, for observations on the intensity of Solar Radiation, to 
be made by Prof. Agassiz, at considerable heights in the Alps, and that the 
sum of 10/. be placed at the disposal of the Committee for that purpose ; " — 
" That Major Sabine be requested to provide a good mountain barometer and 
a thermometer, for the assistance of Mr. M'Cord in his meteorological ob- 
servations — the sum of 20/. to be placed at the disposal of Major Sabine for 
the purpose " — Col. Sabine reported, that M. Agassiz had been supplied with 
two actinometers, at the cost of 10/.; and that a good mountain barometer 
was forwarded to Mr. M'Cord early in the spring of this year, having been 
previously compared with the standard barometer of the Royal Society ; and 
that a thermometer was not sent, because Mr. Newman informed Col. Sabine 
that an excellent standard thermometer had been ordered by Mr. M'Cord 
himself, and had been forwarded to him. The cost of the mountain barome- 
ter was 6/. 12s. 6d. 



Report of a Committee, consisting of Sir J. Herschel only, to super- 
intend the reduction of Meteorological Observations. — July 1841. 

During the last year several series of observations for the years 1837 and 
1838, as well as a few for 1839, have dropped in, and every endeavour has 
been made to procure copies of such as were still wanting from stations 
whence there was reason to presume that observations were forwarded but 
had never come to hand. These endeavours, in several instances, have proved 
successful, and in consequence the list of stations at which available series, 
having some degree of consecutiveness and connexion, can be made out, is 
considerably enlarged. The whole number of series in hand, and under re- 
duction at present, amounts to upwards of three hundred, being the results 
of observations at about seventy stations. 

In the year elapsed, Mr.Birt has been employed intabulating, reducing, pro- 
jecting, and comparing the barometric curves, a process which has been com- 
pleted for the whole of the American group (which is by far the most numerous 
and consecutive) for the years 1835, 1836, 1837, and for March 1838, com- 
prising eighty-eight series, made at the following twenty-eight stations, viz 

Quebec. Western Reserve College. St. Catherine's Island. 

Montreal. Flushing. Magnetic Island. 

Gardiner. New York. Gulf of Guayaquil. 

Burlington. Baltimore. Realejo. 

William's College. Cincinnati. Conchagua. 

Albany. Natchez. San Bias. 

Boston. Washington. Ohreala. 

Providence, R. I. St. Louis. Norfolk Sound. 

Newhaven. Nassau (Bahamas), on shore. 

Middletown. Bahamas, at sea. 

One term also has been reduced and projected (June 1836) for each of 
the other groups, comprising seventeen series, at the same number of sta- 
tions, viz. — 

London. Brussels. Gibraltar, Bangalore. 

Oxford. Hanover. Cadiz. Feldhausen, C.G.H. 

Halifax. Geneva. Mauritius. R. Observatory, C.G.H. 

Limerick. Turin. Dadoopoor. Bathurst. 

Markree. 
making in all 105 series reduced and projected. 



METEOROLOGICAL. OBSERVATIONS. 43 

The tabulated results of these reductions, and their projected curves, accom- 
pany this Report for the inspection of the Meeting. The curves are pur- 
posely projected on a large scale (too large for publication) to afford room 
for a minute examination and analysis of their several inequalities, with a view 
to the possibility of tracing the progress of subordinate undulations or of 
cross waves ; and each has been made by Mr. Birt the subject of particular 
and careful discussion, the results of which he has embodied in the form of 
notes on the, several terms. Many of these contain remarks of much interest, 
especially that on the December term of 1836, which fortunately comprises 
the ascending branches of the barometer curves during a remarkable storm, 
as well as others, which however must be reserved for the final report of your 
Committee, which it may be confidently stated will be ready for presenting 
at the next Meeting. 

Meanwhile the annexed letters from Mr. Birt will serve to give the Meet- 
ing somewhat more than a general idea of the direction which the inquiry is 
taking, and contain some suggestions relative to a system of concerted ob- 
servation excellently well adapted to the tracing of atmospheric waves across 
a tract of country, to which, as well as to his offer to undertake the necessary 
correspondence, your Committee desires to direct the especial attention of the 
Meeting. (Signed) J. F. W. Herschel. 

" Metropolitan Literary and Scientific Institution, June 1, 1841. 

" Dear Sir, — I exceedingly regret that I have been unable to forward you 
the packet containing the projections, &c. of the American observations until 
so long after the time mentioned in my last. I was extremely anxious not to 
omit any point that suggested itself in carefully looking over the projections 
and tables, and having completed this, I hope the packet will reach you in 
sufficient time to enable you to draw up the report for the Meeting without 
inconvenience. 

" The remarks I have to offer I have thrown in the form of notes to each 
sheet of the projections. In these notes I have taken very little, if any, no- 
tice of the curves south of the United States, the Bahamas, &c. I may how- 
ever remark here, that the curves at the Bahamas generally differ from those 
of the United States ; and as they are situated near the northern border of 
the torrid zone this difference is remarkable and interesting, as it indicates 
different systems of oscillation peculiar to the zones. Numerous observations 
from tlie Bahamas, and the West India islands generally, would be highly in- 
teresting. 

" One point which I have glanced at in the notes appears to me interesting 
and worthy of attention in future observations and discussions of this kind, 
namely, the appearance of the diurnal oscillation when the extent of oscilla- 
tion at the station is small, for instance under O'l inches. Generally as the 
oscillation increases the diurnal oscillation becomes obscured. 

" With respect to the tables and projections, I have very carefully examined 
them, and I am not conscious of any errors existing ; the reductions I have 
carefully verified in every instance, and the amount of error in the projections 
is not greater than '0005 in the readings of the barometric altitudes ; this 
amount of error arises from hygrometric causes. 

" With respect to the increase of oscillation, as mentioned in the concluding 
remarks to the notes on the projections, it appears that the stations from 
which observations have hitherto been obtained are too few to derive correct 
conclusions relative to it. Probably, on one or two occasions that may be 
fixed on for future observations, a number of gentlemen may undertake a 
scries of observations of the barometer, having especially this object in view, 



44 REPORT — 1841. 

once or twice, who might not wish to continue such observations at stated 
periods. Our universities and academies, and most of, if not all, our pro- 
vincial institutions, would probably join in this object, and by appointing a 
day sufficiently remote, many gentlemen who would thus engage in the work 
Mould have an opportunity of communicating with their friends, and thus a 
sufficient number of stations well scattered in different and suitable parts of 
the country might be obtained. It appears, however, that in order effectually 
to obtain the object in view, it would be desirable to modify in some degree 
the observations as they have hitherto been conducted ; for, in order to obtain 
the whole extent of oscillation at any station, it would be necessary to obtain 
a complete depression and elevation of the barometric curve. Thus a time 
would be iixed on for a simultaneous commencement of the observations at 
all the stations, say 6 a.m. ; but the termination of the observations would 
depend on the attainment of the elevation or depression of the curve, as the 
case might be ; so that if the barometer was falling at the commencement of 
the observations, they would terminate when the greatest altitude had been 
obtained ; three or four hours' observation after this point had been observed, 
would probably be sufficient to indicate the change in the character of the 
curve. By thus conducting the observations the extent of oscillation at each 
station would be distinctly obtained, as the lowest and highest points of the 
barometer would have been observed. Perhaps you will have the kindness 
to give this subject your consideration, and should it appear to you worth the 
trouble, I shall be most happy to undertake the management of a correspond- 
ence relative to it. " I have the honour to be, dear Sir, 

" Yours very respectfully, 

«W. R. BiRT." 

" Metropolitan Literaiy and Scientific Institution, July 14, 1841. 

" Dear Sir, — 1 have very carefully examined the curves obtained in the 
British Isles, also those in Europe, and have embodied the results of this 
examination in the accompanying notes and tables. 

" The striking difference between the atmospheric affections in the British 
Isles and those of Europe, is highly interesting ; also the difference in the 
lengths of the undulations observed at the European stations, the western 
stations exhibiting the longest. On this point, however, I apprehend the ob- 
servations are not sufficiently numerous to allow of the slightest conjecture 
being entertained, with the exception that there might have existed several 
centres of oscillation, the entire systems extending over comparatively small 
areas, similar to those indicated by the American observations, I believe, of 
September 1837. " 1 remain, dear Sir, yours very respectfully, 

"W. R. BiRT." 



Report of a Committee, consisting of Sir J. Herschel, Mr. Whe- 
WELL, and Mr. Baii^y, for revising the Nomenclature of the Stars. 

As regards the collection of synonyms, the detection of errors originating in 
mistakes of entry, copying, printing, or calculation, and their rectification, 
and the restriction within their just boundaries of the existing constellations, 
the work of your Committee has been progressive. Owing, however, to the 
unfortunate accident which has recently befallen one of its members, by 
whom this department of the work had been especially taken in hand, no 
precise report at this time can be made of the progress made. 

As regards the revision and redistribution of the southern constellations, a 
catalogue has in the first place been prepared of all stars within the circle of 



NOMENCLATURE OP THE STARS. 45 

70° S.P.D, down to the fifth magnitude, with their present actual magnitudes 
as determined by a series of observations made expressly for that purpose ; 
which catalogue is now in course of printing and publication by the Royal 
Astronomical Society. With the magnitudes of this catalogue a chart has 
been constructed, of which several copies have been made. These have been 
employed for the purpose of grouping the stars in various ways (wfthout re- 
gard to existing constellations), and with reference only to forming among 
themselves the most compact and striking groups which their distribution in 
the heavens admits, and which the correctness obtained in the magnitudes 
has now for the first time rendered practicable. After trying many systems, 
and arranging the groups in a great variety of ways, your Committee have at 
length agreed on adopting, as the boundaries of the new regions into which 
they propose distributing the soutliern stars, only arcs of meridians and par- 
allels of declination for a given epoch ; thus including each region within a 
quadrilateral rectangular figure, whose angular points being tabulated in right 
ascension and declination, may be treated as artificial stars, and thus brought 
up by the usual tables of precession to any other epoch, their situation among 
the stars being unchanged. Thus it will become a mere matter of inspection 
of a catalogue arranged for the original epoch (which they propose to be that 
of the Royal Astronomical Society's forthcoming new Catalogue), which re- 
gion any given star shall belong to. 

Proceeding then to assign more particularly the limits of the several regions, 
they have succeeded in forming an arrangement in which (subject to such 
revision and modifications as may arise between this and their final report) 
they feel disposed to rest. Meanwhile, however, as it is of great importance 
that whatever system they may finally adopt should have the sanction of the 
astronomical world in general, it has been thought advisable in the first in- 
stance to lay before the public an outline of the general plan, together with 
a reduced sketch of the proposed regions (subject to such revision), with a 
view to making more generally known its principles, and assembling around 
it, in the event of its approval, that body of support and assent, of which, as 
an innovation, it must stand in need. This has accordingly been done in a 
paper read by one of the members of your Committee to the Astronomical 
Society, and (witli the catalogue above-mentioned) now in course of publica- 
tion. This being largely distributed among astronomers by the printing an 
extra number of copies, will, it is expected, lead to the final maturation and 
reception of the plan. [It was hoped that the printing of this paper, and the 
accompanying engraving, would be far enough advanced to have enabled 
copies to be distributed at the present Meeting of the Association ; but this 
not being the case, proof-sheets of the paper and of the reduced skeleton 
chart are, at all events, annexed to this Report for inspection and perusal by 
such members as may wish it.] 

As respects the nomenclature of the new regions, the Committee are at 
present engaged in considering it ; but some principles, Avhich will probably 
influence their recommendation when the subject is sufficiently advanced for 
that step, are stated in the paper already alluded to, which will appear in the 
forthcoming volume of the Transactions of the Royal Astronomical Society. 

But the same necessity (grounded on the incorrectness of magnitudes as 
laid down in all existing charts) exists for a revision of the northern as well 
as southern stars in this respect. It therefore becomes worthy of considera- 
tion whether a similar plan may not advantageously be carried into execution 
in both hemispheres ; and as, at all events, the actual state of the celestial 
charts in both is such as to admit of great improvement from an assemblage 
of mpre correct photometric data, a general review of all the stars down to 



46 REPORT — 1841. 

the fifth magnitude, with this especial object in view, has been undertaken 
by one of the members of the Committee, conducted on the same plan, the 
principle of which is explained in the paper alluded to. This review is al- 
ready in a considerably advanced state, and should circumstances and weather 
favour will i^robably be completed before the next Meeting. 

In its progress it has required the aid of skeleton charts, prepared by laying 
down all the stars by dots from planispheres of received authenticity, and 
sketching in the existing constellations. As the preparation of such skeletons, 
which require to be very neatly and con-ectly executed, consumes a vast deal 
of time and is very troublesome, they, as well as the southern charts above 
alluded to (thirteen charts in all), have been procured to be executed by 
Mr. Arrowsmith, which has caused an outlay to the amount of 17/. 19s. 6d., 
leaving disposable out of the original grant the sum of 32/. Os. 6d., and which 
the Committee consider will be required for their future proceedings. 

(Signed on the part of the Committee) J. F. W. Herschel. 



Report of a Committee appointed at the Glasgow Meeting of the British 
Association in September 1840, for obtaining Instruments and Re- 
gisters to record shocks of Earthquakes in Scotland and Ireland. 

It is proper to explain at the outset of this Report, that it narrates only what 
has been done by the three individual members of the Committee resident in 
Scotland. It was found by those members impossible to communicate with 
their associates in Ireland in any trials for ascertaining the instruments 
adapted to the object in view. So also, in regard to the localities in Ireland 
and Scotland, where these instruments should be placed, no advantage was 
anticipated from a correspondence between the members of the Committee 
in each country respectively, as it was exclusively those connected with, and 
resident in, the country who knevv the localities where eartliquake shocks 
were most frequent, and where intelligent and careful observers could be 
found. 

The members of the Committee in Scotland had several meetings in the 
beginning of winter to consider some new forms of instruments fitted to re- 
gister the shocks commonly felt in that part of the island. Several instru- 
ments of different forms had previously been constructed and fixed at Comrie 
in Perthshire, but they were found not sufficiently sensitive to indicate more 
than a small proportion of the shocks felt in that district. 

After a good deal of consideration and a number of trials, two kinds of in- 
struments, out of several which suggested themselves, were in the first instance 
resolved on. The one kind was on the principle of the common pendulum, 
the other on that of the inverted pendulum, or watchmaker's noddy. One 
instrument was made on the first-mentioned principle, and two on the second. 
The construction and dimensions of these will now be shortly described. 

1. Common Pendulum Seismometer. — The pendulum is thirty-nine inches 
in length from its point of suspension to its lower extremity. At its lower 
extremity there is a piece of soft chalk in the form of a pencil, which, as the 
pendulum vibrates, makes a marking on a concave piece of wood painted 
black, and forming the segment of a sphere with a radius of thirty-nine inches. 
This segment has white circular lines painted on it parallel with its circum- 
ference, and one inch apart from each other. It has also the cardinal points 
of the compass marked on it. Near the lower end of the pendulum there is 
a leaden ball of about four or five pounds weight, which is perforated through 
the middle, so as to admit the pendulum through it. The chalk pencil 



EARTHQUAKES IN SCOTLAND AND IRELAND. 4f 

presses on the wooden board by a small leaden weight resting on its upper 
end, inside of a metal tube containing the pencil. 

Three wooden rods are fixed to this spherical segment, on its outer edge, 
at equal distances, and unite above the basis, so as to form a point of suspen- 
sion for the pendulum. 

The instrument is fixed by three feet to the floor of a room, and, with the 
help of adjusting screws, the chalk is brought to the centre of the concave 
segment which is to be marked by its vibrations. The concentric circles, 
which are marked 1, 2, 3, &c., from the centre of the segment, indicate the 
number of inches that the lower extremity of the pendulum is thrown from 
the centre ; and the cardinal points show the direction from or to which the 
shock has proceeded. 

2. The Inverted Pendulum Seismometer. — (1.) The smallest of the instru- 
ments made on this principle has a pendulum thirty-nine inches long, and is 
fixed into a brass socket at its lower end. The connexion between the pen- 
dulum and the socket consists of a strong elastic wire, which, by means of a 
pinching screw, can be either raised or depressed in the socket, so as to in- 
crease or diminish the length and sensibility of the pendulum. There is a 
leaden ball near the top of the pendulum from three to four pounds in weight : 
it has a hole through its centre so as to allow the pendulum rod to pass freely 
through it, and it can be fixed at any part of the rod by means of a pinching 
screw. At the upper extremity of the pendulum there is a soft lead pencil, 
which rests on an elastic wire contained in a brass tube. The pencil is thus 
pressed against a white surface of paper, forming the segment of a sphere, 
having a radius of thirty-nine inches. The paper is pasted on a piece of 
copper beaten into the proper shape. This copper segment rests on four 
upright iron rods which are fixed into the base of the instrument. The base 
consists of four corresponding flat iron bars, which cross in the middle, and 
support at that point the socket above described, to which the elastic wire of 
the pendulum is fixed. 

There are on the white segment of this instrument concentric lines in red 
ink, an inch apart, and numbered from the centre, so as to indicate the num- 
ber of inches that the pendulum is by any shock thrown off" its centre. There 
are also on this segment, as on that of all the instruments, points of the com- 
pass to indicate the directions of the shocks. 

The instrument is fixed firmly to the floor of the room where it is set. By 
means of three adjusting screws, which affect the socket, the upper extremity 
of the pendulum is brought to the centre of the segment to be marked by it. 

Any further description of this instrument is rendered unnecessary in con- 
sequence of a paper by Professor Forbes, published lately in the Transactions 
of the Royal Society of Edinburgh, where the mechanism and mathematical 
properties of it are very clearly pointed out. 

(2.) The other instrument constructed on this principle has a pendulum 
ten feet eight inches in length. The spherical segment, on which the vibra- 
tions of its point are intended to be marked, is not, as in the instrument just 
described, supported on upright rods fixed to its base, but is suspended over 
the pendulum by a strong hold-fast of iron fixed into a wall. In other re- 
spects, the mechanical construction of this instrument is much the same as 
that of the former one. 

The above instruments were sent to Comrie, a small town in Perthshire, 
where shocks have been very frequent during the last fifty years, and where 
the earthquake of October 1839 was felt more strongly than in any other 
part of Scotland. They were given in charge to Mr. Peter Macfarlane, Post- 
master at Comrie, a very intelligent person, who had been assiduous in 



48 BEPORT 1841. 

marking down all the shocks which had occurred since October 1839, and 
who had himself contrived and constructed several ingenious instruments for 
indicating the shocks. 

The three instruments were erected in Comrie and the immediate neigh- 
bourhood. The largest of those on the principle of the inverted pendulum 
is in the town of Comrie, and is fixed inside the steeple of the parish church. 
The other instrument on the same principle is at Comrie House, situated about 
a quarter of a mile to the north of Comrie, and taken care of by Colonel 
Simpson, who resides there. The remaining instrument is at a place called 
Garriechrow, close to Cluan Hill, about two miles west of Comrie, and is under 
the immediate charge of the overseer of Sir David Dundas, Bart., of Duneira. 

These instruments were erected a few days before the 1st of January 1841. 
They have been affected only twice, viz. on the 10th and 22nd of March 184'1. 
On the first occasion both of the inverted pendulums had their upper extremi- 
ties thrown to the west half an inch, where they remained till examined. On 
the other occasion they were again thrown to the west, but scarcely half an 
inch. The simple pendulum at Garriechrow has not been affected, and is 
thought to be not sufficiently sensitive. 

The following inferences seem deducible from the way in which the in- 
struments were affected on these two occasions: — (1.) There was, on both 
occasions, a sudden horizontal movement of the ground where both instru- 
ments were placed, indicated by the extremities of them being thrown off 
their centres. (2.) This horizontal movement, on both occasions, was to- 
wards the east. (3.) The amount of this displacement of the ground was, on 
the first occasion, half an inch ; on the second, less than half an inch. 

This last-mentioned inference vvas confirmed by the feelings of those who 
perceived both shocks, as they considered that the first was the most severe, 
though neither was nearly half so severe as the shock of October 1839. 

Mr. Macfarlane states, however, that on both occasions there was a move- 
ment of the earth's crust not indicated by the instruments. He alludes to a 
vertical movement that was sensibly felt, and which on the last occasion was 
indicated by one of his own instruments. 

This circumstance has been alluded to, to show the propriety of having 
instruments of a different kind from the above. Several have occurred to 
members of the Committee calculated for vertical movements ; and these 
movements it is of some consequence to have marked and measured, as it is 
believed they are always produced at Comrie when a shock occurs, and even 
in cases when there may be little or no horizontal movement. 

It is also to be observed, that there is strong reason to believe that the 
Comrie shocks emanate from a particular spot, the exact position of which 
can only be ascertained by a number of instruments placed around the sup- 
posed locality. 

It is hoped, therefore, that the Association will continue the appointment 
of a Committee, and give a renewed grant of money for procuring instru- 
ments and registers. From what has been said, it must be evident that the 
object which was last year thought worthy of being prosecuted cannot be 
properly attained without a greater number of instruments, and some of them 
calculated to indicate vertical movements of the ground. It is also necessary 
that they should be much more sensitive than those now used ; for, though 
there were only two shocks indicated by the instruments, Mr. Macfarlane 
reports, that from the 1st January 1841, when they were in operation, to the 1st 
July, there were no less than twenty-seven shocks distinctly felt at Comrie. 

It is unnecessary to refer, in this Report, to the reasons which induced the 
Association last year to have a regular register of the earthquake shocks oc- 



EARTHaUAKES IN SCOTLAND AND IRELAND. 49 

curring in Scotland. The light which such a register is calculated to throw 
on this dark and important subject is self-evident. The Committee would 
only add, that the value of such a register is now greatly enhanced by its 
appearing that in other countries similar registers are kept, which will afford 
data for comparing the phaeaomena as exhibited in different parts of the 
earth's crust respectively, and ascertaining whether, and to what extent, they 
are connected. In the volume of the Transactions of the Royal Academy of 
Turin, lately published, there will be found a part of the register kept at St. 
Jean de Maurienne from the 19th of December 1838, to April 1840, which 
partly embraces the period comprehended in the Comrie register. 

In urging the continuance of the Committee, and of means to enable them 
to prosecute the object entrusted to them, it may not be out of place to ob- 
serve, that great additional interest attaches to it from the opinion entertained 
by several persons who have attended to the subject, that the earthquake 
shocks of this, and perhaps of other non-volcanic countries, are connected 
with the state of the atmosphere, and more particularly with electrical agen- 
cies. To test the accuracy of this opinion it would be desirable to have 
some meteorological instruments at Comrie, and accurate registers of their 
indications kept. It is unnecessary to say that this opinion, if proved to be 
accurate, would open up new and most important views as to the nature and 
situation of the forces which are concerned in the production of earthquakes. 

If the British Association be still desirous, as it is hoped it will be, of 
having inquiries prosecuted on this subject, it is recommended that a sepa- 
rate Committee should be appointed for Scotland, where the shocks appear 
to be more frequent than in any other part of the United Kingdom, and that 
the Committee should consist of Lord Greenock, Sir John Robison, Professor 
Jameson, Professor Traill, Professor Christison, Professor Forbes, Thomas 
Jameson Torrie, Esq., and David Milne, Esq. 

With regard to the amount of the grant, it is thought that it certainly 
should not be less than what was appropriated last year, viz. 20/. 

(Signed) Greenock, 

David Milne. 

Edinburgh, 10 York Place, 27th July, 1841, 
My DEAR Sir, — I sent you some days ago a Report on the earthquake in* 
struments and registers which have been established at Comrie by the Com- 
mittee of the British Association. 

As a supplement to that Report I now beg to inform you, that on Sunday 
evening, the 25th inst., there were two earthquake shocks felt at Comrie, by 
both of which all the instruments set there were moved. Mr. Macfarlane 
reports,, that the seismometer in Comrie parish-church had its point thrown 
half an inch to the west, which indicated, therefore, a horizontal movement 
of the earth towards the cast. An instrument of my own there also indi- 
cated an upward movement to the extent of half an inch. 

These results, as they strengthen the recommendation in the Report, that 
the Committee therein suggested should be appointed, and a sum of money 
given, I hope you will communicate to the Association. 

Yours very truly, David Milne. 

Extract from a Letter from J. Bryce, Esq., one of the Members of the Com- 
mittee, to D. Milne, Esq., dated Maghera Glebe-House, County of Lon- 
donderry, July 21, 1841. 

Dear Sir, — Since the Glasgow Meeting there appeared in the Irish news- 
papers three notices of earthquakes having occurred ; one in the county of 
1841. E 



60 REPORT — 1841. 

Wexford and two on the North coast. I lost no time in examining into the 
authenticity of these, and I state to you the result merely, without troubling 
you Avith the detail of evidence — there were in reality no earthquakes, the 
effects of sudden squalls were mistaken for those of earthquakes. I did not 
personally collect the evidence, but by letter from a great many most intelli- 
gent, accurate and trustworthy persons, on whom I fully depend. 

You are already in possession of the evidence furnished by Mr. Patterson 
respecting the Innishowen earthquake, about two yeai's ago. It occurred in 
a district composed of granite and slate rocks, and I have no doubt of there 
having been a movement of the ground such as was described. 

I am, dear Sir, yours faithfully, J. Bryce, Jun. 



Report of the Committee for making Experiments on the Preservation 
of Vegetative Powers in Seeds. 

In order to carry out the objects of this Committee, it was deemed advi- 
sable to draw up a series of suggestions for experiments, and to give them an 
extensive circulation. The annexed document has accordingly been printed, 
at a cost of 1/. 14s., and will be distributed at the present meeting. 

The Committee has yet effected but little in the way of direct experi- 
ment. An application was made to the Trustees of the British Museum for 
permission to make experiments on various seeds obtained from the Egyptian 
catacombs. The Trustees have liberally granted permission to their officers 
to select such seeds as could be spared for the purpose. Dr. Daubeny has 
also made a selection of seeds from the old herbaria at Oxford. The speci- 
mens thus obtained have been submitted to experiment, and the results will 
be reported as soon as a sufficient number of data are collected to lead to any 
general conclusions. 

To provide for the expenses incidental to these experiments, the Committee 
recommend that the grant of 10/. made last year should be renewed. 

H. E. Strickland, Secretary to the Committee. 

Suggestions for Experiments on the Conservation of Vegetative Powers in 
Seeds. — These Experiments are intended to determine the following ques- 
tions : — - 

1. What is the longest period during which the seeds of anj^ plant under 
any circumstances can retain their vegetative powers ? 

2. What is the extent of this period in each of the natural orders, genera 
and species of plants ? and how far is it a distinctive character of such 
groups ? 

3. How far is the extent of this period dependent on the apparent charac- 
ters of the seed; such as size, hardness of covering, hardness of internal sub- 
stance, oiliness, mucilage, &c. ? 

4. What are the circumstances of situation, temperature, dryness, seclusion 
from the atmosphere, &c. most favourable to the preservation of seeds ? 

To answer these questions satisfactorily will require the accumulation of a 
large mass of facts ; and although there are many difficulties in the way of 
such an investigation, and many years may elapse before it can be brought 
to maturity, yet it is desirable that the British Association should commence 
the collection of materials for the purpose. It is jsroposed then to invite 
botanists and others to undertake the following series of experiments, and to 
communicate the results to the British Association. 

These experiments are either Retrospective or Prospective. 



PRESERVATION OF VEGETATIVE POWERS IN SEEDS. 51 

A. Retrospective Experiments. 

1. By collecting samples of ancient soils from situations where vegetation 
cannot now take place, and by exposing these soils to air, light, warmth, and 
moisture, to ascertain whether any, and if any, what, species of plants spon- 
taneously vegetate in them. 

N.B Care must of course be taken that no seeds obtain admittance 

into these soils from external sources, — such as the air or water intro- 
duced to promote vegetation. 
These ancient soils are either natural or artificial deposits. 
The natural deposits belong either to past geological periods or to the re- 
cent period. 

a. The deposits of past periods are either secondary or tertiary. 

N.B. — There seems every reason to believe that the age even of the 

latest of these deposits is far beyond the maximum period through 

which vegetative powers can be preserved ; yet as many accounts are 

recorded of seeds vegetating spontaneously in such soils, it would be 

well to set these statements at rest by actual experiment. 

In such experiments, state the formation, and describe the geological phse- 

nomena of the locality, together with the depth from the present surface at 

which the soil was obtained. 

h. Natural deposits of the recent period may be classed as follows : — 
Alluvions of rivers. 
Tidal warp land. 
Shell marl. 
Peat. 
Surface-soil buried by landslips. 

Ditto ditto by volcanic eruptions. 
In these cases, state the nature of the soil, the depth from the surface, &c.; 
and especially endeavour to obtain an approximate date to each specimen of 
soil, by comparing its depth from the surface with the present rate of depo- 
sition, or by consulting historical records. It would be well to submit to ex- 
periment a series of samples of soil taken from successive depths at the same 
locality. 

c. Artificial deposits are as follows : — 
Ancient tumuli. 
Ancient encampments. 

The soil beneath the foundation of buildings. 
The soil with which graves, wells, mines, or other excavations have 

been filled up. 
Ridges of arable land, &c. 
In these cases, state, as before, the depth from the surface, and ascertain 
from historical sources the approximate age of the deposit. 

2. By trying experiments on actual seeds which exist in artificial reposi- 
tories. These are, — 

Seeds in old herbaria and botanical museums. 

Seeds obtained from mummies, funereal urns, at Pompeii, Hercula- 

neum, &c. 
Dated samples of old seeds from nurserymen and seedsmen. 
In these cases, state the circumstances in which the seeds have been pre- 
served, and their date as nearly as it can be ascertained. 

B. Prospective Experiments. 

In this department of the inquiry, it is proposed to form deposits of va- 
rious kinds of seeds under different conditions, and to place a portion of them 



52 REPORT — 1841. 

at successive periods under circumstances calculated to excite tlie process of 
vegetation. In the case of certain species or families of plants, it would per- 
haps require many centuries to determine the limit of their vegetative powers, 
yet it is probable that a very few years would suffice to fix the maximum du- 
ration of the greater number, and that many interesting results might thus be 
obtained even by the present generation of botanists. It is proposed then to 
form a collection of the seeds of a great variety of plants, (including, where- 
ever it is possible, at least one species of every genus,) and to pack them up 
(carefully labelled) either alone, or mixed with various materials, as sand, 
sawdust, melted wax or tallow, clay, garden mould, &c. in various vessels, as 
glass bottles, porous earthen jars, wooden boxes, metal cases, &c., placed in 
various situations, as under-ground, in cellars, dry apartments, &c. At cer- 
tain intervals increasing in extent, — say at first every two years, then every 
five, every ten, and, at the lapse of a century, every twenty years, a small 
number (say twenty) of each kind of seed, from each combination of circum- 
stances, to be taken out and sown in an appropriate soil and temperature, and 
an exact register kept of the number of seeds which vegetate compared with 
those which fail. 

Should it appear desirable for this project to be carried out by the British 
Association, they might most effectually accomplish it by committing a col- 
lection of seeds, formed on the above plan, to some qualified person, whose 
duty it should be, in consideration of a small annual stipend, to take charge 
of them, and at stated periods to select portions for experiment, keeping an 
accurate register of the results. 

In this manner it is believed, that in regard to the large majority of plants, 
the limit of their vegetative durability would be determined in a very few 
years, and that a large mass of vulgar errors on this subject, which now pass 
current for facts, would be cancelled and exploded. 

N.B. — The most effectual way of exciting vegetation in seeds of great 
antiquity, is to sow them in a hot-bed, under glass, and in a light soil 
moderately watered. 



On Inquiries into the Races of Man, by Dr. Hodgkin. 

Dr. Hodgkin read a Report, from which the following are extracts, respect- 
ing the drawing up, printing, and circulation of Queries concerning the human 
race, for the use of travellers and others. 

" The list of Queries, as presented in a printed form to the Meeting last 
year, has undergone revision and correction, and may now be regarded as 
comprising Queries relating to every branch of the subject with sufficient 
minuteness to suggest inquiry and invite reports from travellers of different 
tastes and acquirements. An edition of the Queries in their present form has 
been printed off, and copies have already been extensively circVr'ated, but there 
has not been sufficient time to admit of the return of replies from those parts 
of the globe from which they are the most to be desired. 

" Copies have been furnished to the British Museum, to the Royal Geo- 
graphical Society, and to other scientific bodies, foreign as well as British. 
Considerable pains have been taken to place them in the hands of intelligent 
travellers about to visit those quarters in which natives exist, but of whom 
imperfect accounts have hitherto reached us, and whose altered condition, or 
extermination, is likely in a short time to deprive us of the possibility of ob- 
taining a knowledge of what they have been, unless it be promptly collected. 
On the occasion of the fitting out of a well-appointed expedition to ascend the 
Niger, and thus penetrate into the interior of Africa, copies were furnished 



INQUIRIES INTO THE RACES OP MAN. 53 

to the commanders of the vessels, and to the intelligent naturalists and drafts- 
men who formed a part of their suite. Very recently, intelligence has reached 
this country, that an expedition, well equipped on all points, is about to pro- 
ceed, for the purposes of scientific inquiry, from the southern shores of the 
Red Sea, in a south-westerly direction, with the hope of reaching the Cape 
by a somewhat circuitous route. Should this expedition happily succeed in 
its undertaking, it will necessarily have to pass through the midst of nations 
and tribes of Africans, of whom a more extensive as well as correct know- 
ledge is, notwithstanding all the research hitherto employed, still essentially 
necessary for our possessing anything like an accurate view of the characters 
and distribution of the African races, and for our arriving at any well- 
grounded conclusions concerning the modes, directions, periods, and circum- 
stances of their diflusion over the continent, and of the influence which they 
have reciprocally excited upon each other by fusion, by reduction of num- 
bers, or by the change of their physical and social condition. Several copies 
of the Queries are now in the way of transmission to the gentlemen com- 
posing that expedition. They are accompanied by some observations sug- 
gested by circumstances peculiar to the mission, and the regions through 
which it is designed to pass. 

" Sir George Simpson, the Governor of the Hudson Bay Company's terri- 
tory, having a few months since left this country with the intention of cross- 
ing the North American Continent, from Canada to Vancouver, of visiting 
the Russian settlements, and of passing over land by Kamtschatka to Peters- 
burgh, the opportunity was not lost to endeavour to increase the interest 
which he already has felt in the character and situation of the several tribes 
with whom his oflScial situation necessarily brings him into contact. Copies 
of the Queries were furnished, not only for the governor's own use and that 
of Dr. Rowand, an intelligent medical man, partly of Indian descent, who 
was expected to accompany the governor in his entire route, but also for 
such residents at the Company's settlements as might be judged likely to turn 
them to good account. Several copies have likewise been addressed to cor- 
respondents already settled in remote situations. Although it is to be feared 
that many of the copies which have been thus distributed may fail to procure 
from those who receive them the direct i-eplies which they call for, it is not 
too much to hope, that, from various quarters, detailed series of answers may 
be received, and found in no small degree to contribute to the interest and 
advantage of the sittings of this Section at future Meetings of the Associa- 
tion. It is perhaps not too much to anticipate, that in this way the diffusion 
of these Queries may not only serve the too-much neglected cause of the 
science of Ethnography, but indirectly promote a practically benevolent 
interest in some of the feeble and perishing branches of the human family. 
Even in those cases in which direct replies are not obtained, some good may 
not unreasonably be looked for from the juere fact of their directing the 
attention of the reader to a great variety of points connected with the scat- 
tered families of man. In many minds they may originate trains of thought, 
and excite interest, inquiry, and investigation ; and even with tliose who 
have no means of making investigations of their own, they may yet serve to 
create an appetite for information of a kind which at present is, in general, 
but little appreciated, and consequently but sparingly supplied. Neverthe- 
less, the interests of science, of our country, and of humanity at large, arc 
essentially connected with this subject. When it is considered that other 
countries, which have immeasurably less direct interest in the condition of 
the uncivilized sections of the human race, and who, as respects wrongs to 
be atoned for, and advantages to be reaped, may be regarded as all but 



54 REPORT — 1841. 

foreign to it, are notwithstanding pursuing it with zeal, it certainly behoves 
us, for the credit of our country, to endeavour to diffuse a more extensive 
and operative interest in relation to it." 

Dr. Hodgkin stated that sufficient time had not elapsed for the return of 
answers from distant countries. Some interesting information had, however, 
been elicited by them from a gentleman who had lately travelled in Texas, 
where he had observed the remnants of the ancient Mexicans. He pointed 
out some of the national reasons which call for exertion on the part of 
Englishmen, and related some of the labours of foreigners, and more espe- 
cially of the Ethnographical Society of Paris, of Dr. Dieffenbach, R. H. 
Schomburgk, and other Germans, and those of the government as well as of 
individuals of the United States, and gave a description of the gallery of 
North American Indian curiosities and portraits collected and exhibited with 
great expense and pains by George Catlin, whose work on the Indians of 
North America he announced as nearly ready for publication. Dr. Hodgkin 
dwelt on the importance of Ethnological researches, and on the absolute 
necessity for promptly pursuing the work if anything valuable and satis- 
factory is to be accomplished ; seeing that the races in question are not only 
changing character, but rapidly disappearing. 

" It is this threatened extinction of races of men who have been either 
wholly neglected or very imperfectly studied, which seems to bring this sub- 
ject peculiarly within the province of this Section of the British Association. 
Why should not the varieties of our own species receive as much attention 
as those of inferior animals, however remarkable or rare they may be ? Has 
the extinction of a variety of man ever excited equal attention with that 
which has been paid to the loss of the dodo ? Or has the diminution of any 
tribe of Aborigines received a proportionate share of solicitude with that 
which has been given, not to the extinction of a species, but to its disappear- 
ance from a particular hcality, as in the case of the ' cock of the woods,' from 
the northern parts of this island ? Successful attempts have been made to 
restore these animals to their ancient haunts ; and it has even been contem- 
plated to restore the long-lost wild boar to the list of British wild animals. 
A rare variety of the ox or the dog is preserved with unremitting care, and 
often at great expense, from generation to generation ; and a rare specimen 
in any department of natural history is sought with unremitting perseverance, 
preserved with pains, and purchased at an almost unlimited expense. It is not 
to disparage the zeal which is justly devoted to any of the various branches 
to which these objects may belong, that these observations are offered ; they 
are merely made for the purpose of urging that man himself, even as an object 
of Natural History, may receive a degree of attention proportioned to the 
exalted rank which he holds amongst the works of his Creator. A great variety 
of interests are united in ascertaining the mode in which man, as the highest 
of animals, has been diffused over the surface of the globe." 

Dr. Hodgkin concluded by urging, as practical means for advancing the 
cause of Ethnological investigation, first, the bringing home, for the purpose 
of being studied themselves, as well as of being made the subjects of suitable 
education, well-selected aboriginal youths, and especially such as have had an 
opportunity of acquiring knowledge, and exhibiting ability in missionary or 
other native schools. This plan, which need not equal in expense what is 
often done for other objects of zoology and for botany, might be facilitated 
by the union of individual contributors. Secondly, rendering personal and 
pecuniary aid to the Aborigines' Protection Society, the objects of which were 
neither of a party nor of a sectarian character, but were solely directed to the 
preservation, amelioration, and study of the feeble races of mankind, amongst 



EXPERIMENTS WITH BALLOONS. 55 

which those related to British colonies occupied the chief place. Dr. Hodg- 
kin observed, that the objects pursued by this Society furnished subject- 
matter not merely for the Zoological, but also for the Medical and the Sta- 
tistical Sections. Details of the plans, operations and present state of the 
Aborigines' Protection Society may be obtained from its publications, which 
are to be had at the Society's Office, 17 Beaufort Buildings, Strand. The 
Queries regarding the races of man, to which this report refers, will be found 
in another part of this volume. 



Report of the Committee appointed to report how far the Desiderata in our 
knowledge of the Condition of the Upper Strata of the Atmosphere may be 
supplied by means of Ascents in Balloons or othertvise, to ascertain the 
probable Expense of such Experiments, and to draw up Directions for Ob- 
servers in such circumstances. 
Although much valuable information might be obtained by means of 
aerostatic observation, the pecuniary outlay which would be required for 
this purpose is so considerable, that the Committee do not at present recom- 
mend any application of the funds for this object, much less any attempt to 
induce Her Majesty's Government to incur the expense, until the plan has 
been more fully matured. But experience derived from ascents made under 
ordinary circumstances, as opportunity may offer, would be desirable, both 
as regards the kind of instruments, the mode of using them, the special 
points to be attended to, the degree of concordance to be expected in results 
obtained at diiferent times, places, and states of the atmosphere. The prin- 
cipal objects required are, to determine the progression of temperature, and 
the law of the distribution of vapour, in ascending from the surface of the 
earth to the upper regions of the atmosphere. There can be no doubt that, 
in a perfectly dry and undisturbed atmosphere of air, the temperature would 
be found to decrease as we ascend, as the density decreases ; and that this 
must be its normal state to which, amongst all its fluctuations, it must tend. 
The decrease of density, however, is liable to the action of various disturbing 
causes, the principal of which are the evolution of heat by the local conden- 
sation of vapour, and its absorption by the evaporation of clouds. The law 
of the decrease would most probably be elicited from the mean results of a 
great number of careful observations, in which a compensation of such dis- 
turbances Avould take place; but it cannot be expected that it should be 
apparent in such a limited series as can be comprised in a single ascent. It 
is probable that the temperature observed at short intervals, instead of pre- 
senting a regularly decreasing progression, would exhibit great irregularities ; 
as, for instance, that it would be found in a calm to decrease to a certain 
point, then become steady for a time, or possibly rise, especially upon passing 
through a cloud, or upon entering a current flowing in a different direction 
from that upon the surface : or, if the condensation of vapour were taking 
place from the action of a cold wind flowing into, and mingling with, a 
saturated atmosphere, instead of arising from the regular decrease of tem- 
perature due to the decreased density, a sudden and great depression would 
be found. The observer's attention should be particularly directed to the 
influence of clouds or changes of currents upon the thermometer. Mr. Green 
has found that the isothermal planes are parallel, or nearly so, to the earth's 
surface, so that the aeronaut knows generally, even although the earth may 
be intercepted by a cloud, when he is crossing a chain of hills ; or at least 
the upper surface of the clouds generally follows in a great measure the con- 
figuration of the earth. " The upper surface of the clouds, upon occasions 



56 REPORT — 1841. 

when they overspread the earth at a moderate elevation, seems to accom- 
modate itself to all the variations of form in the subjacent soil." Mr. Green 
has also found, that it is usual to ascend to a greater elevation to experience 
the same reduction of temperature when the earth is overspread with clouds 
than in a cloudless sky. According to Mr. Monck Mason, a singular rela- 
tion is found to exist between the formation or precipitation of rain, and the 
condition of the sky above the clouds which contain it. " Whenever from a 
sky completely overcast with clouds rain is falling, a similar range of clouds 
invariably exists- in a certain elevation above, whereby the rays of the sun 
are intercepted from the layer below ; and on the contrary, whenever, with 
the same apparent condition of the sky below, rain is altogether or generally 
absent, a clear expanse of firmament, with a sun unobstructed by clouds, is 
the prevailing character of the space immediately above : thus leaving it a 
determinate fact, that when rain is pouring from clouds overspreading the 
earth, the rays of the sun are not operating upon the clouds in question ; 
while, on the other hand, rain does not fall from such clouds when the rays 
of the sun are unobstructedly falling upon the upper surface." According 
to the same authority, and in conformity with the opinion of Mr. Green, it 
appears that, in this country, whatever may be the direction of the wind 
below, in the higher regions, that is, generally within 10,000 feet above the 
surface of the earth, the direction of the wind is invariably from some point 
between the north and west. It appears from Mr. Green's observations, that 
" the variation experienced in the course of the wind during the progress of 
the ascent was accompanied by a corresponding alteration in the intensity of 
its rate, the current which at the commencement was gentle becoming strong 
as it took another direction, and vice versa." These important facts in 
Meteorology could not have been ascertained by any observations made at 
the surface of the earth, and afford strong evidence of the advantages which 
might result to science from well-planned aeronautic expeditions. With 
regard to the atmosphere of vapour, it is probable that it tends to the main- 
tenance of an analogous but very different progression of density and tem- 
perature, from below upwards, to that of the gaseous atmosphere ; but being 
constrained to diffuse itself through the latter, it is controlled and regulated 
by the temperature into which it is thus forced. Thus the elasticity with 
which it will rise from the surface of the earth, in the act of evaporation, 
will be determined by the temperature of some upper stratum of the air, at 
which it will become condensed, the force at which point will limit by its 
reaction that of the evaporating surface. Between these two points, there- 
fore, the dew-point will probably be found to be steady, or to decline by a 
very slow progression. After passing through the cloud, it may be expected 
that the dew-point will fall at once several degrees ; the elasticity of the 
vapour on the upper side being probably governed and determined by a new 
point of condensation in still higher regions, just as the dew-point on the 
surface of the earth is conceived to be determined by the temperature of the 
first vapour-plane. This would imply, that while precipitation was taking 
place on one side of a bed of clouds, rapid evaporation might be going on 
upon the other. It is also conceivable that these processes of condensation 
and evaporation may be so adjusted as that they may exactly counteract each 
other ; and the vapour-plane might thus be indicated by no cloud, or possibly 
by a mere haze ; but the dew-point would fall suddenly. To this circum- 
stance the observer's attention should be particularly directed. It is probable 
that, in ascending to a great height, several vapour-planes might be thus 
crossed, and the confirmation of the hypothesis would be of importance to 
science in elucidating the constitution of the atmosphere. It is obvious that, 



EXPERIMENTS WITH BALLOONS. 57 

for the purposes just indicated, the observations of the thermometer and 
dew-point should, if possible, be unremitted during the whole time both of 
the ascent and descent, and, of course, must be accompanied by simultaneous 
observations of the barometer : one person's time should therefore be wholly 
devoted to these objects ; and the arrangement should be well considered, by 
which his labour may be facilitated and his attention kept undistracted. The 
prevailing forms and structure of the clouds ; their internal motions, if any ; 
the number of strata which may be detected, and the number and direction 
of the currents which their motion may indicate, will also form interesting 
objects of observation in conjunction with the preceding. Contemporaneous 
observations will, of course, be made on the earth during the time of the 
aerostatic voyage, which will possess a greatly-increased interest if circum- 
stances should permit it to take place on the day when hourly meteorological 
observations are made at all the principal observatories of Europe, according 
to the plan laid down by Sir J. Herschel. Portions of the air should be 
brought down, for examination, from the highest elevations ; and this may 
probably be best effected by taking up several glass balloons, or bottles care- 
fully gauged, fitted with stop-cocks, and filled with water. The water should 
be allowed to run out at the proper station, and the stop-cocks closed. Ex- 
periments upon the radiation of heat, by another observer, would also be 
interesting, although there are probably no knpwn means of instituting them 
with all the accuracy which could be desired. Observations with Sir J. Her- 
schel's actinometer might be made upon the force of solar radiation at various 
heights ; but the instrument would not be applicable to the measurement of 
terrestrial radiation. When a delicate thermometer, whose bulb is covered 
with lamp-black, is placed in the focus of a parabolic reflector, and turned 
towards the clear sky, even in the day-time, it will radiate a portion of its 
heat into space ; by the same contrivance, the rays of heat proceeding from 
the earth, or from beds of clouds, would be condensed upon the thermometer, 
and some estimate formed of their intensity. Observations upon these points 
at different heights, and at different periods of the day and night, would be 
instructive, though not of the high importance which would belong to those 
of the thermometer and hygrometei*. To these observations might be added 
others of great interest upon the electricity of the atmosphere, by dropping 
wires into clouds, or from stratum to stratum of cloudless air, and examining 
the nature of the electricity of their extremity by means of a very delicate 
electroscope : but attractive as these researches may prove, the Committee 
recommend, that should a series of ascents be undertaken by one or many 
observers, on no occasion should the observer's attention be distracted by too 
great a variety of objects ; and that our efforts should at first be directed 
solely to the elucidation of the question of the decrease of temperature, by 
the acquisition of accurate contemporaneous observations of the barometer 
and thermometer made at different elevations. It would manifestly be 
desirable, that Avhile observations of atmospheric temperature and pressure 
were made in a balloon, two observers, stationed at the extremities of an 
accurately measured base, and provided with theodolites of the best con- 
struction, should by their observations determine the height of the balloon 
geometrically, at the instants the observations of tempei'ature and pressure 
were made. This, however, implies a more extensive system of cooperation, 
and a larger personal and instrumental force, than could probably be assem- 
bled. It will, therefore, be best to confine the observations simply to the 
determination of corresponding teiuperatures and pressures of the atmo- 
sphere. For this purpose nothing more is wanted than a supply of instru- 
ments that can be easily used and give accurate results. 



58 REPORT— 1841. 

Of the Hygrometer. — It is desirable that two hygrometers should be pro- 
vided, which may be fixed side by side upon the lid of a box, into which 
they may be contrived to pack. The observer should not only note the tem- 
perature of the first appearance of dew, but the temperature at which it 
again disappears ; and wlaile he is waiting for the last observation by one in- 
strument, he may proceed to make a new one with the other. A store of the 
best aether should be provided, and a convenient dropping-bottle. No dis- 
advantage would arise from the effect of the diminished pressure upon the boil- 
ing-point of the aether, if placed in a bottle contrived for the purpose ; as thus, 



-r 



n, ab the bottle, 



3I c d the level of the asther, 

ef a tube fitted tight into the neck, and passing to the bottom of 

** the liquid, furnished with a stop-cock e. As the atmospheric 

^ pressure diminished upon the aperture of the stop-cock, the 

^ * pressure of the included vapour would pour out a stream of 

aether, which might be regulated, and the rapidity of its subsequent evapora- 
tion would be a great advantage ; but as it is probable that the dryness of 
some of the upper sections of the atmosphere may be extreme, smaller tubes, 
filled with condensed sulphurous acid, should be provided, and kept cool in 
ice, by the dropping of which upon the bulb of the hygrometer extreme cold 
may be produced. As an additional precaution, a small bright silver capsule 
and delicate spirit-thermometer may be prepared, by which the dew-point 
may be observed from the direct evaporation of the acid. Bottles containing 
a mixture of liquid carbonic acid and aether might perhaps be prepared, 
which would answer the purpose still more perfectly. As it is extremely 
desirable that the relation of the cold produced by evaporation from the sur- 
face of a wet-bulbed thermometer with the dew-point should be ascertained, 
and as such an observation would not add much to the trouble of the 
observer. Dr. Mason's hygrometer, which is a convenient form of the instru- 
ment, may be fixed upon a stem upon the box, immediately behind the 
hygrometers, and the temperatures of the two thermometers may be noted. 
The freezing of the water in the upper regions will, however, put an end to 
these observations. The stem which supports the thermometers may also be 
made to carry a moveable card-board, covered on the outside with gilt paper, 
so as to screen all the instruments from direct radiant heat. 

Of the Barometer. — The only barometer that can be used, and can be 
trusted in observations like those in question, appears to be the Siphon-baro- 
meter of Bunten, in Paris (Quay Pelletier, No. 26), or barometers of a 
similar construction by Robinson, of London. The tubes of Bunten appear 
to be carefully made ; the column of mercury is easily seen ; and the slow 
motion of the verniers, though not so fine as in Robinson's, is more easily 
managed, a circumstance of some importance in the present instance. The 
barometers should be new : their scales divided in millimetres only. Some 
of them have a scale of English inches, which, owing to some mistake about 
standard temperature, is very erroneous. They should be always kept in- 
verted, except when in actual use. When allowed to hang in the position in 
which they are used, the mercury in the short tube becomes oxidized, the 
glass covered with a powder of the oxide, and the capillary depression con- 
siderably increased, which renders the instrument useless. In a cistern- 
barometer, where the level of the mercury cannot be observed, the cor- 
rections for a change of level for small variations of barometrical pressure 
are extremely troublesome. For large changes of barometrical pressure they 
must become uncertain in the highest degree. Troughton's mode of deter- 
mining the lower level is decidedly bad. The cistern-barometers, in which 





EXPERIMENTS WITH BALLOONS. 59 

the lower level is determined by contact of a point with the surface of mer- 
cury, are good comparative or differential instruments, but nothing more. 

Of the Thermometer. — The best and most convenient thermometers appear 
to be those made by Greiner, of Berlin, witli a paper scale enclosed in an 
outer tube, or a scale of milk-white glass. The bulbs are 
exposed, and the scales cannot be injured by immersing the 
bulbs, or whole instrument in water, or any other liquid, 
for purposes of comparison. The graduation should extend 
from —85° Fahr. to about -|- 100° Fahr. In Gay-Lussac's 
ascent, the thermometer descended 40° 25". It is not likely 
that any observers would ascend much higher than he did, 
or that they would undertake an ascent Avhen the tempera- 
ture at the earth's surface was less than 10° C. The ther- 
mometers, during the ascent, should be enclosed in bright 
tin tubes (having an opening through which the scale can 
be observed), open at both ends, with a round disc of tin at 
a little distance from the ends, to prevent the effect of radi- 
ation. Thermometers thus protected were used at the Cambridge Observa- 
tory, and found to answer well. The temperature of the air being already 
known, one thermometer with a wet bulb will be sufficient to determine the 
pressure of vapour at a given station. 

Directions for Observing. — When the motion of the balloon in a vertical 
direction appears to be small. 1. Observe the thermometer attached to the 
barometer. 2. Make the lower edge of the upper ring appear to touch the 
upper end of the mercurial column. 3. Make the lower edge of the lower 
ring appear to touch the lower end of column. 4. Observe the thermometer 
in the tin case for temperature of air, and note the time. 5. Read off the 
two verniers of the barometer. 6. Observe the psychometer (wet-bulb ther- 
mometer) and Daniell's hygrometer. The observations at the surface of the 
earth should be made in the same order. The observers should avoid as 
much as possible approaching the thermometer and barometer, in order that 
they should not influence the temperature. The aeronaut must be instructed 
in making the contact between the ring and the end of the mercurial column, 
also in reading a vernier correctly. 

Cost of Instruments. 

Two of Bunten's barometers, each 4/. Ss £ 8 1 6s. 

Duty, 25 per cent 2 4 

Two thermometers, each 1/. lis. 6rf. 3 3 

Duty, 25 per cent 16 

Same, to be used with wet bulbs 3 3 

Duty, 25 per cent 16 

£18 18s. 
Tin cases for thermometers, Daniell's hygrometer, &c. 
It would be manifestly imprudent to commence operations with only just a 
sufficient stock of such fragile instruments as barometers and thermometers. 
Duplicates of every one should be provided. This would make the cost of 
the instruments amount to about 50/. To the above might be added, — a 
sympezometer, constructed for the purpose, without sliding scale, — a maxi- 
mum and minimum thermometer, about as large as a watch, constructed by 
Breguet. 

(Signed) David Brewster, Edward Sabine, 

J. F. W. Herschel, W. Whevvell, 

J. W. Lubbock, W. H. Miller. 

T. R. Robinson, 



60 REPORT — 1841. 

Report on British Fossil Reptiles. By Richard Owen, Esq.^ 
F.R.S., F.G.S., ^c. ^'c. 

Part II. 

The British Fossil Reptiles described in the first part of this Report pre- 
sented modifications of their osseous structure, and especially of the vertebral 
column and locomotive extremities, by -which they were especially adapted 
for a marine life, and hence have been collectively termed Enaliosauria. 
All the numerous species of this family are extinct, and it seems that the 
genera have ceased to be represented since the deposition of the chalk for- 
mations. In the present zoological systems the Plesiosauri and Ichthyosauri 
are referrible to the Saurian order of reptiles, as defined by Cuvier ; but they 
offer the most remarkable deviations from the existing types, and constitute 
links which connect the Reptiles, on the one hand, with Fishes, and, on the other 
hand, with the cetaceous Mammals. 

The present and concluding part of the Report on British Fossil Reptiles 
contains an account of the remains of the Crocodilian, Dinosaurian, Lacer- 
tian, Pterodactylian, Chelonian, Ophidian and Batrachian reptiles. 

The most remarkable of the extinct species of the amphibious and terres- 
trial Sauria of England have been discovered and described by Dr. Buckland 
and Dr. Mantell. Some remains are briefly noticed by Parkinson*, and by 
the older English observers, as V/ooller and Chapman. Cuvier has added to 
the value of these discoveries by his just observations and comparisons. Some 
of the British Chelonian fossils have been noticed by Parkinson, Cuvier and 
Dr. Mantell ; but none of the British extinct Ophidians or Batrachians appear 
to have been hitherto recognized as such. 

Pliosaurus. 

The Enaliosaurs are immediately connected with the Crocodilian reptiles 
by an extinct genus, represented by species of gigantic size, of which the 
remains are not unfrequent in the Kimmeridge and Oxford clays. The Reptile 
in question is essentially a modified Plesiosaurus, but its modifications appear 
to entitle it to be regarded as a distinct genus, which, as it is more closely 
allied to the true Sauria, I have proposed to call Pliosaurusf. 

Large, simple, conical teeth, with the enamelled crown traversed by well- 
defined and abruptly terminated longitudinal or oblique ridges, as in the 
teeth of the Plesiosaur, have not unfrequently been discovered in the Kim- 
meridge clay formation. These teeth differ from those of the Plesiosaur in 
their greater relative thickness as compared with their length, and in the 
subtrihedral shape of their crown ; the outer side is slightly convex, sometimes 
nearly flat ; it is separated from the two other sides by two sharp ridges ; these 
are more convex, and the angle dividing them is often so rounded ofl^ that 
they form a demi-cone, and the shape of the tooth thus approximates very 
closely to that of the Mosasaur, with which it is equal in size. It may be 
readily distinguished, however, even when the crown only is preserved, by 
the ridges which traverse the inner or convex sides, the outer flattened surface 
alone being smooth ; but an entire tooth of the present extinct Reptile presents 
a long fang, which at once removes it from the acrodont group of lacertine 
Saurians, and allies it with the thecodont Reptiles, among which it approaches 
nearest, in the superficial markings of the crown, to the Plesiosaur. 

The known parts of the skeleton of the gigantic extinct reptile, to which the 
teeth in question belong, confirm this approximation ; but the vertebrae of the 

* Organic Remains of a Former World, vol. Hi. 
t Odontography, Part II., p, 282. 



ON BRITISH FOSSIL REPTILES. 61 

neck are so modified, that the peculiarly elongated proportion of this part of the 
spine, which characterizes the typical Plesiosaurs, is exchanged for one that 
much more nearly approaches the opposite condition of the cervical region 
in the Ichthyosaurs. This abrogation of the main characteristic of the Ple- 
siosaurs, combined with the more crocodilian proportions of the teeth, esta- 
blishes the claims of the Pliosaurus to generic distinction. 

In the collection of Professor Biickland, at Oxford, is preserved a consider- 
able proportion of both the upper and lower jaws of a gigantic specimen of 
the Pliosaurus, from the Kimmeridge clay formation at Market-Raisin. The 
teeth are arranged in separate sockets, in a close and regular series, along the 
alveolar borders of the intermaxillary, maxillary and premandibular bones. 
Twenty-six sockets may be counted on the most perfect side of the upper jaw; 
but the series is evidently incomplete posteriorly. An interspace, not quite 
equal to the breadth of a socket, divides the fourth from the fifth tooth, count- 
ing backwards, and the jaw is slightly compressed at this interspace ; the four 
anterior teeth, thus marked off, occupy the slightly expanded anterior extre- 
mity of the upper jaw, but do not present the excessive size of the correspond- 
ing teeth in the Plesiosaur. After the fifth tooth the sockets progressively 
increase in size to the twelfth tooth, and from the fourteenth they begin gra- 
dually to diminish in size, becoming, beyond the twentieth tooth, smaller than 
those at the fore part of the jaw. 

The alveolar septa are narrow, and are thinned off to an edge, which is lower 
than either the outer or inner walls of the sockets : these walls are equally de- 
veloped. A line drawn transversely across any of the twelve anterior sockets 
would be transverse to the jaws, but in the remaining sockets it would incline 
obliquely from without, inwards and backwards. The transverse diameter of 
the thirteenth socket is one inch six lines ; its antero-posterior diameter is one 
inch eight lines. 

The extent of the alveolar series in both jaws is nearly three feet; the 
breadth of the palate at the twenty-sixth tooth is nearly one foot ; the breadth 
of the upper jaw at the third tooth is four inches and three lines ; the breadth 
of the socket of that tooth is one inch three lines. 

In the lower jaw of the specimen in the Oxford Museum, the posterior ex- 
tremity of the dental series is complete, but not the anterior one ; thirty-five 
teeth are present in each premandibular bone. The first, from its large size, 
I conclude to have been received into the slight concavity at the side of the 
upper jaw, where the diastema separates the fourth and fifth teeth ; there are 
probably, therefore, thirty-eight teeth on each side of the lower jaw. Counting 
backwards, on this supposition, the teeth begin to diminish in size beyond the 
fifteenth, and at the posterior extremity of the series the sockets are less than 
half an inch in diameter : in their close arrangement and position they corre- 
spond with those of the upper jaw. 

The teeth which are preserved in this magnificent cranial fragment, present 
the characters above defined. The insei-ted fangs of most of these teeth are 
four inches in length ; the entire tooth being thus seven inches in length. 
The ridges which divide the outer from the inner surfaces of the tooth sub- 
side at the base of the crown ; the fang is smooth ; it assumes a subcircular 
form, gradually expands for about half its length, and then contracts to its 
termination ; but this is always less pointed than in the fully formed teeth 
of the true Plesiosaur. In the old teeth with the elongated fang, the pulp 
cavity remains open, as in the Plesiosaurian teeth ; it presents at the expanded 
part of the fang a narrow elliptic transverse section. In a tooth of the present 
species, six inches and a half in length from the Kimmeridge clay at Shotover, 
the diameter of the persistent pulp-cavity was thirteen lines. In this tooth 



62 REPORT — 1841. 

the flattened surface is polished, but marked with minute shallow wrinkles ; 
one of the ridged surfaces, which stood at right angles to the preceding, was 
traversed by eleven well-marked linear ridges of unequal length, separated 
by smooth interspaces of about three times the breadth of the ridges ; the 
third surface, which formed an acute angle with the smooth outer surface, 
was traversed by twelve ridges. These ridges, on the inner surface of the 
tooth, slightly inclined towards the rounded angle, dividing the surfaces ; they 
terminate abruptly ; some cease half way from the apex of the crown ; about 
ten are continued to within half an inch of the apex, which is smooth ; the 
two ridges, which divide the flat or smooth side from the ridged surfaces of 
the tooth, are alone continued to the subacute apex of the tooth. 

The teeth of the Pliosaur present varieties of form as well as of size ; the 
rounding off" of the angle between the ridged surfaces has been already alluded 
to ; the smooth outer surface is sometimes so convex, that the transverse 
section of the tooth is more elliptical than triangular. All the teeth of the 
Pliosaur are slightly bent inwards and backwards ; but the smaller posterior 
teeth are most recurved, and have the sharpest apex ; and in the crown of 
these teeth the ordinary rounded or elliptical form of the cone is most 
nearly attained ; but the distinction of the smooth external surface, and the 
ridged internal surfaces of the crown of the tooth are retained, and would 
suffice to characterize any of these teeth if found detached. 

The teeth consist of a central body of compact dentine, with a coronal 
investment of enamel, and a general covering of cement. The dentine is 
permeated by fine calcigerous tubes, without admixture of medullary canals. 
The arrangement, division, secondary undulations, and branches of the cal- 
cigerous tubes closely correspond with those of the teeth of the Plesiosaur. 
The germs of the successional teeth in the Pliosaur were developed at the 
inner side of the basis of the old teeth, but did not penetrate these teeth ; the 
apices of the new teeth make their appearance through foramina situated at 
the inner side, and generally at the interspaces of the sockets of the old teeth. 
Here, therefore, as perhaps also in the Pterodactyle, the growing teeth may 
be included in closed recesses of the osseous substance of the jaw, and 
emerge through tracts distinct fi'om the sockets of their predecessors, which 
is an exceptional condition of the reproduction of the teeth in reptiles. 

Of the Vertebral Column. — A long neck has been considered to be so 
peculiarly the distinction of the Plesiosaur, that a species which has this 
part of the spine shortened and reduced by the flattening of the vertebrae to 
Ichthyosaurian proportions, may be reasonably regarded as at least subgene- 
rically distinct, especially when the enormous and massive head, to which the 
abbreviated neck bears a subordinate relationship, is armed with teeth which 
have just been shown to be as remarkable for their thickness and strength as 
those of the Plesiosaurus are for their slender and sharp-pointed proportions. 

Perhaps there is no example, save the genus Pliosaurus, in the whole class 
of reptiles, living or extinct, which has any of the vertebrae presenting such 
proportions as those of the followijig specimen in Dr.Buckland's collection from 
the Kimmeridge clay of Foxcombe Hill, near Oxford. The breadth of the 
body of this vertebra is six inches ; its depth, or vertical diameter, five inches ; 
while in length, or the diameter corresponding with the axis of the body, 
it measures only an inch and a half. But cervical vertebrae of similar pro- 
portions have been discovered in the Kimmeridge clay near Weymouth, and 
were described by Mr. Conybeare in the ' Geological Transactions.' The 
Market-Raisin specimen in the Oxford Museum proves that those peculiarly 
compressed vertebrae are associated with the well-defined teeth characteristic 
of the Oxford and Kimmeridge clays, and with jaws of great size, which could 



ON BRITISH FOSSIL. REPTILES. 63 

only be supported and wielded by a neck as short and strong as in the Ceta- 
ceous inhabitants of the sea. 

The cervical vertebrae, as they recede from the head, increase in breadth 
and depth, but retain the same length, as they do throughout the spine in 
most Saurians, whatever may be their other dimensions. But in the dorsal 
region of the spine of the Pliosaur, the vertebrae acquire a great increase of 
length, and there assume the ordinary proportions of Plesiosaurian vertebras : 
for example, the first dorsal vertebra of the Market-Raisin specimen, which 
is four inches three lines in breadth, and four inches in depth, measures 
nearly three inches in length. The posterior dorsal vertebrae slightly in- 
crease in depth, and with the same transverse diameter they present a length 
of 3 inches 2 lines. The height of one of these vertebrae, including the 
spinous process, is 11 inches. These proportions are retained at least to the 
base of the tail. A vertebra from this part, obtained from St. Giles's gravel- 
pit, near Oxford, and probably washed out of the Kimmeridge clay, measures 
in length 3 inches ; in the breadth of the body, 4 inches 9 lines ; in the depth 
of the same, 4 inches 4 lines. 

In the extreme difference which the vertebrae of the neck and those of the 
rest of the trunk present in regard to their length, the Pliosaurus forms a 
remarkable exception to Saurians in general ; for in the true Enaliosaurs, in 
Crocodiles, in Lizards, whatever other modifications the vertebrae may undergo, 
or however much they may be expanded in breadth or depth, they maintain 
great constancy in the length or antero-posterior diameter of the body. The 
Pterodactyles, or flying-lizards, offer another exception to this rule, and the 
cervical region is here likewise the seat of the variation ; but whereas in the 
Pliosaur the cervical vertebrae are remarkable for their shortness ; in the Pte- 
rodactyle they differ from the other vertebrae in their extreme length. 

The general structure of the vertebrae of the Pliosaur corresponds closely 
with that of the Plesiosaur. The osseous texture is compact at the circum- 
ference of the vertebras, and coarsely, but uniformly, cellular in the rest of 
the bone. The neurapophyses do not become anchylosed to the centrum, 
nor the ribs to the costal processes. The articular surfaces at each end of the 
centrum are flat in the cervical, very slightly concave in the dorsal, rather 
more concave in the caudal vertebrae. The cervical ribs, judging from their 
articulation with the centrum, must have been unusually strong. The rib on 
each side of the vertebra was supported on two transverse processes, slightly 
raised beyond the level of the centrum, occupying two-thirds of its antero- 
posterior extent, and divided by a deep and well-marked linear fissure. In 
the anterior cervical vertebrae above described, with a length of 1 inch 9 lines, 
and a height of centrum of 3 inches 3 lines, the antero-posterior diameter of the 
constant surfaces was 1 inch 2 lines ; their united vertical diameter, 2 inches 
2 lines. They occupy a space nearly equi-distant from the upper and lower 
surfaces of the centrum. At the base of the neck they begin to rise, as in the 
Plesiosaur, upon the neurapophysis, and are supported, in the dorsal region, 
upon a single stout transverse process. This is subdepressed, with an oval 
transverse section, which is rather sharp at the anterior margin. The spinous 
process of the dorsal vertebrae is nearly straight, compressed laterally ; its an- 
tero-posterior diameter was 2 inches 8 lines ; in a vertebra, measuring in the 
same diameter 3 inches 2 lines, its height from the base of the neurapophysis 
was 7 inches. The sides of the centrum are rather rugous near the articular 
ends, elsewhere smooth and concave, especially in the dorsal vertebrse. The 
lower surface has the two vascular perforations in the cervical regions ; the 
vertebrse become slightly contracted towards this part in the dorsal region. 
In the caudal vertebrae the costal process is single, vertically elliptical, and 



64 REPORT — 1841. 

« 

prominent. The non-articular surface of the centrum is not very regular, but 
is smooth ; the lower surface is square-shaped, and nearly flat ; its angles are 
marked by the haemapophysial surfaces, of which the anterior pair is the 
largest. 

Bones of the Extremities. — The type of construction of the bones of the 
extremities closely accords with that of the Plesiosaur. The pectoral arch 
owes its chief strength to a pair of immensely expanded coracoids, having a 
broad and short entosternal bone on their anterior interspace, and supporting 
the clavicles, or the acromial productions of the scapulae. 

The femur of the Market-Raisin specimen measures two feet two inches in 
length, and is thirteen inches broad at its distal end — a bone well fitted to 
support and wield the strong paddle that must have been mainly instrumental 
in propelling this carnivorous sea-monster through its native element. 

In another femur, measuring thirteen and a half inches across the distal 
end, the circumference of the proximal end was nearly two feet ; the upper 
half of the bone is cylindrical ; it gradually exclianges this for a compressed 
expanded distal end, which is terminated by a pretty regular convex curve. 
The texture of the bone is coarsely cellular throughout, being devoid, as in 
other marine Saurians, of any trace of medullary cavity. 

One of the siibcircular carpal bones of the Market-Raisin specimen mea- 
sured five and a half inches across the broadest part, and four and a half 
across the narrowest, and was two and a half inches in thickness. 

The phalanges are short and less compressed than in the Plesiosaurs ; flat 
at the articular extremities, and remarkably contracted in the middle. 

Besides the localities affording specimens from which the general descrip- 
tion of the bones of the trunk and extremities is taken, and which localities 
are noticed in that description, remains of the Pliosaur have been discovered 
in the following localities : — A small cervical vertebra from Shotover, in 
the Oxford Museum ; four dorsal vertebrae, equal in size with the Market- 
Raisin specimen, from Marcham, also in the Oxford Museum ; the vertebra 
in the Yorkshire Museum*, said to have been found in the gravel of Burn, one 
mile below Nunnykirk, Northumberland, and noticed in the first edition of 
Lyell's ' Principles of Geology,' is a posterior cervical of a Pliosaurus, and 
must be presumed to have been accidentally introduced into that recent de- 
posit. The several specimens from these different localities yield strong indi- 
cations of two distinct species of the presept gigantic genus, which connects 
the Enaliosaurs with the Coelospondylian Crocodiles. The difference in breadth 
and height, and especially in the size of the hatchet-bone, or cervical rib, as 
indicated by the articular surface, appear to be inexplicable, except on the 
supposition of two distinct species. The difference is continued in the dorsal 
vertebrae, the transverse processes of which are more compressed, and the non- 
articular surface more rugous in the Shotover than in the Market-Raisin spe- 
cies. The two forms of femora, on which the species Plesiosauri grandis 
and trochanterius are founded in the former part of this Report, are both 
referable to the genus Pliosaurus ; but have not as yet been found so asso- 
ciated with vertebrae as to aid, in combination with the vertebral characters, 
in the definition of the two species. When subsequent discoveries and ob- 
servations shall have supplied distinct and recognizable characters to the two 
species of the present very remarkable and interesting annectant genus, the 
term hrachydeirus, which I had first proposed for the species represented by 

* In the Yorkshire Museum there is preserved a humerus of a Pliosaur from the lower part 
of the Kimmeridge clay deposit at Speaton, which measures thirteen inches in length, and 
seven inches across the distant end : the femur of the same specimen measured sixteen 
inches in length. 



ON BRITISH FOSSIL REPTILES. 65 

the magnificent remains from Market-Raisin*, would be equally applicable 
to the short-necked gigantic Pliosaur from Shotover, and consequently lose its 
value as a distinctive appellation. 

CROCODILIA. 

The remains of species of this order extend from the Eocene tertiary for- 
mations as low down as the Oolite and Lias, and offer deviations from the 
structure of the existing genera and species, which increase in degree and 
amount as the strata containing the extinct species indicate periods more 
remote from the present time. 

Not any of the species are identical with those now known to exist, and the 
modifications of the' osseous structure, by which the extinct Crocodilians differ 
both from the present races and from one another, are much greater than any 
of those by which the skeletons of the existing species differ among themselves. 
Not only do the form and proportions of the periphei'al parts, as of the jaws, the 
teeth, and the locomotive extremities vary, but the spine, or central axis of the 
skeleton, offers modifications of the articular surfaces of the component verte- 
brae whicli are quite unknown in the Alligators, Crocodiles and Gavials of the 
present epoch. In these existing species the anterior surface of the vertebral 
centrum is concave, the posterior convex, except in the atlas and sacrum. But 
besides this mode of junction, Cuvier has recognized in the Crocodilians of 
the secondary formations two other types of vertebral structure : in one of 
these the positions of the ball and socket are reversed ; in the other, and more 
common modification, both articular surfaces of the vertebra are flat or slightly 
concave. Remains of extinct Crocodilians, exhibiting all the three systems 
of vertebral articulation, occur in English formations. The extinct species, 
which agree with the existing Crocodilians in their vertebral characters, will 
be first described. 

a. fVith concavo-convex Vertebrcs. 

Crocodilus Spenceri, Buckland. 

' Crocodile de Sheppj/,' Cuv. 

The most recent stratum in which I have met with the remains of extinct 
Crocodiles in Great Britain is the Eocene deposit called th^ London clayf. 
A third cervical vertebra from the Isle of Shcppy, is noticed by Cuvier as 
being very similar to the corresponding bone in an existing Ci'ocodile, and as 
having appertained to an individual of probably five feet in length. No other 
part of this Eocene reptile is noticed in the last edition of the ' Ossemens Fos- 
siles;]:.' A fine cranium is preserved in the British Museum; and Dr. Buck- 
land § has figured a smaller but better preserved specimen of the Sheppy 
Crocodile, in the collection of E. Spencer, Esq. I have examined both these 
specimens, and have compared them with the skulls of the recent Crocodilians. 

In Mr. Spencer's fossil, the end of the snout, including the intermaxillaries 
and nostrils, is broken off; the tympanic pedicles, pterygoid alas and occipital 
tubercle, and the crown of the teeth are also wanting. The principal and 
most characteristic differences which the Crocodilus Spenceri presents in 

* Odontography, p. 283. 

t Cuvier makes mention of the calcancum of a Crocodile in the collection of M. G. A. 
Dcluc, said to liavc been discovered at IJrnntford in the year 1791, associated witli the re- 
mains of tlic Mammoth, Hippopotamus, Rhinoceros and i)cer, and wliich bore incontcstaI)le 
marlis of a distinct species, lie observes that if this hone; lunl not been tvansporti'd to its 
present situation, with the debris of otlicr strata, it would be the most recent of the remains 
of tlie genus of Crocodile. — Loc. cit., p. 33G, vol. ix. 

X 8vo, 183G,vol. ix. ]). 327. 

§ ISridgewatcr Treatise, vol. i. p. 251, pi. xxv. fig. 1. 
184.1. F 



66 REPORT — 1841. 

reference to the Crocodilus hiporcatus, or other existing species of Crocodile 
or Alligator, are the larger size of the temporal holes as compared with the 
orbits, the more regular and rapid diminution of the head towards the snout, 
the straight line of the alveolar tract, and the greater relative length and 
sienderness of the muzzle, which is evident notwithstanding its imperfect 
condition. These differential characters are equally manifest in the larger, 
and in some respects more perfect specimen, of the cranium of this species 
in the British Museum. 

Amongst existing Crocodiles, the Bornean species, called Crocodilus Schle- 
(/elii, most resembles the Crocodilus Spenceri. But in the Sheppy Crocodile 
the posterior smooth surface of the occiput is less concave ; its upper boun- 
dary line is indented in the middle by the termination of a median longitu- 
dinal depression upon the upper surface of the skull, which is not present in 
the existing species, in which the corresponding surface is flat. The de- 
scending process of the basi-occipital, below the articular tubercle, is smoother 
in the Crocodilus Speiiceri ; the interorbital space is flatter : the upper tem- 
poral foramina equal the orbits in size — a character by which the Crocodilus 
Spenceri manifestly approaches the Gavials. The nasal and superior maxil- 
lary bones are smoother ; the sloping profile line of the face is straighter, and 
the lateral converging lines of the upper jaw are straight. These characters 
are well shown in the British Museum specimen. 

The upper jaw slightly expands about one-third from its termination, then 
contracts, and again expands at the muzzle. At this anterior part the bones 
are more pitted than they are nearer the cranium. The alveolar margin 
seen in the whole skull is slightly undulating. The jugal bone is slender and 
nearly horizontal. The lower jaw has a large elliptical vacuity at its ex- 
panded posterior part. Its alveolar risings correspond with the sinkings of 
the same part in the upper jaw. In all these characters it corresponds with 
the Crocodilus Schlegelii of S. MUUer. 

Upon the lower surface of the skull the pterygoids in the Crocodilus 
Spenceri are terminated anteriorly by a broader and straighter transverse 
line ; from the middle of which the palatines are continued, their posterior 
extremities not being expanded, as in the Crocodili vulgaris or hiporcatus, 
but of the samei breadth as the rest of the bone. The anterior and internal 
curved border of the transverse bones is more regular. The dental series 
terminates posteriorly nearer the anterior part of the transverse bone. The 
teeth, If^o = 84, are more uniform in size, and more regularly spaced ; 
the intervals, however, vary from 1 1 to 2 and 3 lines ; and that between the 
first tooth in Mr. Spencer's mutilated specimen and the second equals 7 
lines. The diameter of the base of the crown of the tooth is 3 lines : there 
are nine of these teeth in the same extent as that which includes eleven teeth 
in a specimen of the Crocodilus vulgaris, having a skull of similar breadth. 
The teeth in the Crocodilus Spenceri are subcircular, Avitli an anterior and 
posterior longitudinal ridge, with intervening fine longitudinal sti'iae. 

The sculpturing of the cranial bones is very similar in the recent and fossil 
Crocodiles, but the facial bones are smoother in the Crocodilus Spenceri, as 
they likewise seem to be in the Crocodilus Schlegelii. 

The following dimensions are taken from the skull of the Crocodilus Spen- 
ceri in the British Museum : — 

Ft. In. Ln, 

Length of cranium from the lower end of the tympanic bone to 

the beginning of the nostril 2 

Breadth of ditto between the articular end of the tympanic bones 10 

From the articular end of the tympanic to the orbit 8 6 



ON BRITISH FOSSIL REPTILES. 67 

' Ft. In. Ln. 

From the orbit to the nostril 14 6 

Breadth of the cranium across the orbits 7 6 

Ditto five inches in advance of orbit 3 8 

Ditto across the first expansion of the jaw 4 

Ditto across the nostril , 2 8 

Depth of lower jaw at the posterior vacuity 3 6 

Length of the vacuity 3 

Breadth of the base of a tooth at the first expansion 8 

In the museum of Fr. Dixon, Esq., at Worthing, there is a fine fossil, re- 
ferable to the Crocodilus Spenceri, from the Eocene clay of Bognor. It 
consists of a portion of the skeleton, including the lumbar, sacral, and five 
of the caudal vertebras, in a continuous chain of ten inches in length, but 
bent in an abrupt curve. 

The vertebras, as compared with those of the Crocodilus acutus, have the 
sides of the centrum deeper or more extended vertically, and they are slightly 
concave ; the first caudal is, as usual, bi-convex, the under surface is rather 
flattened. The femur presents the usual sigmoid curve, it has a well-marked 
medullary cavity ; its length is five inches six lines. Mr. Dixon possesses, 
from the same locality, a posterior cervical vertebra of a Crocodile, similar in 
general characters to those just described, but larger, and probably belong- 
ing to an older individual. The length of the body of this vertebra is two 
inches and a half. 

Remains of Crocodilians occur in the London clay at Hackney, and in the 
Eocene sand-beds at Kyson, in Suffolk ; I have seen from this locality small 
bifurcate finely-striated conical teeth, and a small bony scutum, with regular 
and pretty deep pits, about the size of pins' heads. 

/3. With biconcave Vertebrce. 

SUCHOSAURUS CULTRIDENS. 

Gavial of the Tilgate Forest, Mantell. (?) 
Teleosaurus , H. v. Meyer. 

I next proceed to notice the fossil Crocodiles from the more recent second- 
ary formations, and shall commence with those species with biconcave verte- 
briB, the remains of Avhich are characteristic of the Wealden beds. 

Amongst the evidences of Crocodilian Reptiles which are scattered through 
the Tilgate strata the most common ones are detached teeth, from the differ- 
ence observable in the form of which. Dr. Mantell has observed, that " they 
appear referable to two kinds ; the one belonging to that division of Croco- 
diles with long slender muzzles, named Gavial; the other to a species of Cro- 
codile, properly so-called, and resembling a fossil species found at Caen *." 

Dr. Mantell has obligingly communicated to me figures of well-preserved 
specimens of both the forms of teeth alluded to, the exactness of which I 
have recognized by a comparison with the specimens themselves in the 
British Museum. 

The tooth which, from its more slender and acuminated form, approaches 
nearest to the character of those of the Gavial, differs from the teeth of any 
of the recent species of that sub-genus of Crocodilians, as well as from those 
of the long and slender-snouted extinct genera, called Teleosaurus, Steneo- 
saurus, &c. I have described this form of tooth fj therefore, as indicative 

* Wonders of Geology, 1839, vol. i. p. 386. 
t Odoutography, pi. Ixii. A, figs. 9 and 10. 

f2 



68 REPORT— 1841. 

of a distinct species, under the name of Crocodilus cultnde7is* . The crown 
is laterally compressed, subincurved, with two opposite trenchant edges, one 
forming the concave, the other the convex outline of the tooth. In the 
Gavial, the direction of the flattening of the crown and the situation of the 
trenchant edges are the reverse, the compression being from before back- 
wards, and the edges being lateralf . The tooth of the Crocodilus cultridens 
thus resembles in form that of the Megalosaur, and perhaps still more those 
of the Argenton Crocodile ; but I have not observed any specimens of the 
Wealden teeth in which the edges of the crown "were serrated, as in both the 
reptiles just cited. The teeth of the Crocodilus cultridens also present a 
character which does not exist in the teeth of the Megalosaur, and is not at- 
tributed by Cuvier:(: to those of the Crocodile d'Argentofi. The sides of 
the ci-own are traversed by a few longitudinal parallel ridges, with regular 
intervals of about one line in breadth, in a crown of a tooth one inch and a 
half in length : these ridges subside before they reach the apex of the tooth, 
and sooner at the convex than at the concave side of the crown. 

Hitherto these teeth have not been found associated with any part of the 
skeleton of the present extinct Crocodilian; but from the well-marked dif- 
ferences between these teeth and those of all other known species, it is most 
probable that the extinct Crocodile formed the type of a distinct sub-genus, 
for which the term Suchosaurus might be applied. 

In the Wealden strata, biconcave Crocodilian vertebrae have been dis- 
covered by Dr. Mantell differing in form from those of the Crocodilian with 
obtuse teeth, and readily distinguishable by their compressed and wedge- 
shaped body from those of all other known Crocodilians. It is highly pro- 
bable that these remarkable vertebrjE are parts of the same animal as the 
above described and equally remarkable compressed teeth. 

No. 2133, Mantellian Collection, is the body of a dorsal vertebra of this 
species of Crocodilian, with both articular extremities slightly and equally 
concave : though rather narrower at the middle than at the ends, it is more 
uniformly compressed than in other Crocodilian vertebraj, the sides con- 
verging to an inferior obtuse ridge, which is very slightly concave in the 
antero-posterior direction. The sides are not flat in the vertical direction 
nor slightly concave, as in many of the Iguanodoiis vertebras, to which the 
present form approximates ; but are gently convex, so that a pencil laid ver- 
tically upon the side touches it only by its middle. A more decided differ- 
ence between the present crocodilian vertebras and those of the Iguanodon 
is, that the former are longer in proportion to their height and depth. The 
external surface at the middle of the body of the vertebra is very finely stri- 
ated, so as to present a silky appearance ; near the margins it is sculptured 
by coarse longitudinal grooves and ridges. 

The base of the neurapophysis, which, when anchylosed, leaves an evident 
trace of the suture, is nearly equal in length with the body of the vertebra ; 
it does not wholly include the spinal canal, but leaves the impression of the 
lower third of that canal upon the upper surface of the centrum. 

* Tl\ese teeth are referred by M. II. v. Meyer to the genus Teleosaimis ; but no portions 
of the skeleton of a Telcosaur have hitherto been found in the Wealden. Tlie figures of 
the teeth of Suchosam-us cultridens, published ))y Dr. Mantell in the ' Illustrations of the 
Geology of Sussex,' pi. v. lig. 5, 6, 8, ai-e those cited in the ' Palseologica,' p. 115. The other 
teeth attributed to the same species of Teleosaurus, hy II. v. Meyer, out of Mantell, I. c. 
pi. V. figs. 1, 2, 7, 9, 10, 11, appertain to a genus equally distinct from Suchosaurus and from 
Teleosaurus. 

t The tootli attributed by M. Deslongchamps to the PoiMlopleuron, agrees in form w^th 
those of the Gavial, and differs in the characters cited in the text from those of the Croco- 
dilus cultridens. % Cu\'icr, i.\. p. 331. 



ON BRITISH FOSSIL RE>PTILES. 69 

In No. ^, Mantellian Collection, the bases of the neurapophysis remain 
attached to the centrum, which presents the same characters as No. ~. On 
the outside of the neurapophysis are two slightly developed broad obtuse 
ridges, converging towards each other from the outer side of each angle or 
end of the base of the neurapophysis ; the ridge corresponding with the pos- 
terior of these in the Igtianodons vertebra rises more vertically, and is in 
higher relief. 

The neurapophysial suture slightly undulates in its horizontal course, and 
rises in the middle instead of descending upon the centrum, as in the Ple- 
siosaurs. 

The present vertebra is alluded to at p. 70, and figured at pi. ix. fig. 11, of 
Dr. Mantell's ' Illustrations of the Geology of Sussex,' as a lumbar vertebra 
of the Megalosuurus. But in the ' Geology of the South-east of England,' 
the accomplished author, speaking of this vertebra, observes, " It cannot, I 
now think, be separated from those figured in the same plate, as belonging 
to a crocodile." — p. 297. Fig. 8, pi. ix, (Tilgate Fossils) is, however, a 
caudal vertebra of the Cetiosanrus. As I have examined with care the ori- 
ginal vertebra of the Megalosuurus, figured after Buckland, and referred to 
by Dr. Mantell at pi. xix. fig. 16 of the same work, I can attach the greatest 
confidence to the following difierences : — the body of the Megalosaurian 
vertebra has a pretty deep longitudinal depression below the neurapophysial 
suture, wanting in the Tilgate vertebra here described. This, however, is 
not the only distinction ;, below the depression the body of the Megalosaurian 
vertebra swells out, and is as convex below as it is laterally in the transverse 
direction, so that the outline of a transverse section would describe five-sixths 
of a circle: a similar section of No. 123 would be triangular with the apex 
rounded off'. The Megalosaurian vertebra is more contracted at the middle, 
and swells out near the articular ends, surrounding those articulations with a 
thick convex border : in No. 123 the lateral meet the marginal surfaces at a 
somewhat acute angle ; but the silky striated surface of the Crocodilian ver- 
tebra, and the smooth and polished surface of the Megalosaurian one, would 
effectually serve to distinguish even fragments from the middle of the body 
of each. 

The following are dimensions of the two vertebrae of the large Wealden 
Crocodilian above described : — 

No. 123. No. 138. 

In. Lines. In, Lines. 

Antero-posterior diameter of the body ... 3 4- 3 10 

Vertical diameter of its articular end .... 2 5 3 2 

Transverse diameter of its articular end ... 2 10 2 9 

Transverse diameter of the middle of the body 2 2 

GONIOPHOLIS CRASSIDENS, O. 

Swanage Crocodile, Mantell. 

Teleosaurus , H. v. Meyer. 

The second form of tooth having the generic characters of those of the 
Crocodile, which has been discovered in the Wealden and approximate strata, 
is as remarkable for its thick, rounded and obtuse crown as the teeth of the 
preceding species are for their slender, compressed, acute and trenchant cha- 
racter. It consequently approaches more nearly to the teeth which charac- 
terize the broad and comparatively short-snouted Crocodiles ; but it differs 
from these in one of the same characters by which the tooth of the Sucho- 
saurus cultridens differs from those of the Gavials, viz. in the longitudinal 
ridges which traverse the exterior of the crown. These are, however, more 



70 REPORT — 1841. 

numerous, more close-set, and more neatly defined than in the Suchosaums 
cultridens. Two of the ridges, larger and sharper than the rest, traverse 
o])posite sides of the tooth, from the base to the apex of the crown; they 
are placed, as in the Crocodile and Gavial, at the sides of the crown, mid- 
way between the convex and concave lines of the curvature of the tooth. 
These ridges are confined to the enamel ; the cement-covered cylindrical 
base of the tooth is smooth. The size.of the teeth varies from a length of 
crown of two inches, with a basal diameter of one inch and a half to teeth of 
one-third of these dimensions. 

Hitherto no teeth of the Goniopholis appear to have been discovered 
in the oolite near Caen ; the only specimens resembling them being those 
which Cuvier has stated to indicate a second species of Crocodilian, from the 
Jura limestone at Soleure*. No other remains referable to this species are 
noticed by Cuvier ; but the discovery of a portion of the skeleton, having in 
the lower jaw two teeth identical with the obtuse teeth of the Wealden, has 
thi'own much light upon the characters of this interesting species. 

The circumstances connected with this discovery are thus narrated by Dr. 
Mantell : — " In the summer of 1 837, the workmen employed in a quarry in 
the immediate vicinity of Swanage, had occasion to split asunder a large slab 
of the Purbeck limestone, when, to' their great astonishment, they perceived 
many bones and teeth on the surfaces they had just exposed. As this was 
no ordinary occurrence, — for although scales of fishes, shells, &'c. were fre- 
quently observed in the stone, bones had' never before been noticed, — both 
slabs were carefully preserved by the proprietor of the quarry." They were 
obtained by Robert Trotter, Esq., F.G.S., and presented by him to Dr. 
Mantell, by whom the bones were relieved from the matrix, so far as their 
brittle state would permit. The specimen has subsequently been purchased 
by parliament, and, with the rest of Dr. Mantell's collection, is now depo- 
sited in the British Museum. 

Figures of this interesting group of bones have been published by Dr. 
Mantell in his ' Wonders of Geology,' vol. i. pi. i.; but, excepting the remark 
above quoted, with regard to the nearer approach which the fossil makes in 
the form of its teeth to the sub-genus Crocodilus, as compared with the more 
slender Wealden tooth, no other observation has been published which tends 
to establish more precisely and closely the true affinities and nature of the 
Swanage Crocodilian. 

The first character which attracts attention is that which the numerous, 
large, bony, dermal plates or scutes afford. These are scattered irregularly 
over the slab, and in their number and relative size bring the species much 
nearer to the extinct Teleosaurs thaii to any of the existing Crocodiles ; they 
differ, however, from both the dorsal and ventral scutes of the Teleosaur in 
their more regular quadrilateral figure ; they are longer in proportion to their 
breadth than most of the Teleosaurian scutes, and are distinguished from 
those of all other Crocodilians, recent and fossil, that I have yet seen, by the 
presence of a conical, obtuse process, continued from one of the angles verti- 
cally to the long axis of the scute, analogous to the peg or tooth of a tile, and 
fitting into a depression on the under surface of the opposite angle of the 
adjoining scute ; thus serving to bind together the plates of the imbricated 

* " On trouve parmi ces os dii Jura une petite dent pointue et tin pen tranchante, fort 
semblable a celle du Crocodile de Caen," I. c. ix. p. 283, pi. ccxxxiv. fig. 8, i. e, the Teleo- 
saurus Cadomensis, the teeth of which are " longues, greles, arquees, et tres-pointues, mais 
non pas tranchantes." Ibid. p. 271. Cuvier then proceeds to say, " Mais il y en a aussi de 
beaucoup plus grosses et plus obtuses, telles que celle de la fig. 7, qui pourraient annoucer 
une autre espece." Ibid. p. 283. It is with tliis other species that the blunt-toothed Croco- 
dilian of the Wealden and Purbeck limestone bears most resemblance. 



ON BRITISH FOSSIL REPTILES. 7l 

bony armour, and repeating a structure which is highly characteristic of the 
large bony and enamelled scales of the extinct ganoid genera of fishes, Dape- 
dius and Tetragonolepis. Many of the scutes are 6 inches in length and 2^ 
inches in breadth. 

The exterior surface of the scute is impressed, as in the Teleosaur, by 
numerous deep, round, or angular pits, from two to four lines in diameter, 
and with intervals of about two lines, formed by convex reticularly disposed 
ridges of the bone ; but a larger proportion of the anterior part of the scute 
is overlapped by the contiguous scute than in the Teleosaur, and this part is 
smooth, and thinner than the rest of the scute. The whole of the inner sur- 
face of the scute is smooth ; but on a close inspection it is seen to be every- 
where impressed by fine straight lines, decussating each other at nearly right 
angles, and indicating the structure of the corium in which the scutes were 
imbedded. From the size and strength of these dermal bones, their degree 
of imbrication, and the structui-e for interlocking, we may conclude that the 
Swanage Crocodilian was better mailed than even the extinct Teleosaur, which 
Cuvier regarded as " I'espece la mieux cuirassee de tout le genre." 

If the detached vertebrse from the Wealden, communicated by Dr. Mantell 
to Cuvier, belonged to the obtuse-toothed species and not to the Sitchosaurus 
cultridens, it would then have been known that the Swanage Crocodile de- 
viated, like the Teleosaur and most extinct Crocodilian species of the secondary 
strata, from the Crocodiles, Alligators, and Gavials of the present day, in having 
both articular extremities of the body of the vertebra slightly concave. 

Cuvier* has associated the obtuse teeth with this form of vertebra without 
hesitation ; but it must be admitted that there was room for some doubt, two 
distinct species, at least, having been indicated by the fossil teeth. 

In the slabs between which the remains of the Swanage Crocodile are di- 
vided, the vertebrai were unfortunately all at right angles to their plane, and are 
fractured across the middle, one extremity being buried in one of the halves 
of the slab, and the other in the opposite half. By permission of the Trus- 
tees of the British Museum, and the kind aid of the distinguished Mineralo- 
gist at the head of the Geological Department, this doubt has been solved 
since the reading of the present Report at Plymouth. The limestone has 
been carefully removed from the two extremities of the same vertebra, and 
both are equally but slightly concave. 

In. Lines. 

The length of the body of the vertebra examined was . . 1 10 

Vertical diameter of the articular extremity 1 9 

Transverse diameter of the articular extremity .... 1 8 

Ditto of middle of the body Oil 

Ditto of entire vertebra, including the transverse processes 10 

Height of entire vertebra, including spinous process . . 4 4; 

From the lower part of the centrum to the base of the \ cy n 

transverse process J 

There is a small irregular medullary cavity in the centre of the body of 
the vertebra : this cavity is much more capacious in the Poikilopleuron : the 
exterior compact crust of the body of the vertebra is about two lines in thick- 
ness. The suture which joins the neural arch to the centrum is conspicuous ; 
it forms an ascending angle or curve at its middle part. The body of the 

* " Les vertubves sont un peu concaves aux deux extremites, ce qui les rapproche du Croco- 
dile de Caen et du deuxieme de ceiLX de Honfleur; cepcndant je les trouve plus voisines du 
premier pour rensemblc. Les dents sont pour la plupart plus obtiises nicnie que dans nos 
Crocodiles vulgaircs, et ressembleut en ce point a la seconde du Jiua que j'ai decrite ci- 
dessus." — L. c, p. 323. 



72 REPORT — 1841. 

vertebra expands in a greater degree to form the snbconcave articular sur- 
faces than in other biconcave vertebrse of the same length ; and both in this 
character, in its smooth surface, and circular transverse contour at the lower 
part, the Goniopholis resembles the Streptospondylus more than it does the 
Teleosaums. 

The medullary canal, at the middle of these vertebrae, presents in trans- 
verse section the form of an inverted triangle, the apex sinking into the body 
of the vertebra. The transverse processes of the lumbar and anterior caudal 
vertebrae are long, straight, and comparatively slender ; those of the sacral 
vertebrae arc relatively thicker, and the spaces inclosed by their expanded ex- 
tremities are smaller than in either the Teleosaurs or true Crocodiles. The 
antero-posterior extent of the two sacral vertebrae is three inches two lines. 

The ilium is broader than in the existing Crocodilians ; the bifurcation of 
the proximal end of the ischium is more marked, and the iliac branch is more 
regularly rounded ; the pubic branch is longer, more slender, and its articular 
end is more regularly convex ; the distal or lower part of the ischium expands 
into a relatively broader plate. This character is still more conspicuous in 
the pubis, M'hich equals the ischium in breadth, and begins to expand much 
nearer the proximal extremity than in the existing Crocodiles. In these 
modifications of the pelvis, as well as in the biconcave structure of the ver- 
tebra, the Crocodilian of the Purbeck limestone approaches nearer to the 
characters of the Enaliosaurs ; and we may infer that its habits were more 
decidedly marine than are those of existing Crocodilians. The caudal verte- 
brae were provided Avith long, narrow, unanchylosed chevron bones. 

The portion of the lower jaw preserved belongs to that part of the left ramus 
included between the articular extremity, which is broken off, and the com- 
mencement of the dental series ; it measures one foot six inches in length, and 
five inches in greatest depth. In these proi^ortions, and the curve of the lower 
margin, it deviates from the ancient Teleosaurs and Steneosaurs, and resembles 
the modern Crocodiles ; and although not quite equalling these in the robust 
proportions of the jaws, yet it much exceeds in this respect the Crocodilians 
with more slender teetli. What the i-eal length and form of the jaws may 
have been, and how nearly they may have approached the Gavial type, there 
is not at present means to determine. Sufficient, however, has been pointed 
out from the remains which are at present discovered, to show that the Swanage 
Crocodilian differs from the existing subgenera of Crocodilians in a greater 
degree than these do from one another; that in the form of its vertebrae and 
the structure of the dermal armour, it is much more nearly allied to the 
Teleosauri and other Crocodilian genera of the biconcave vertebral system ; 
and that, in this ancient and extinct group of Crocodilians, it typifies the 
Alligator family of the Crocodilians of the ball-and-socket vertebral sj'stem. 

I propose to name the subgenus indicated by the known remains of the 
Swanage Crocodile, Goniopholis, in reference to the rectangular form, size, 
number, and firm junction of the osseous scutes (cjioXiSes), with the specific 
name of " crassidens." 

In a collection of fossil Saurian remains from the Hastings beds in the 
possession of Gilpin Gorst, Esq., F.G.S., is the base of the tooth of the Go- 
niopholis crassidens, eight lines in diameter. 

Remains of Crocodilians are stated by Dr. Mantell to have been found, 
though very rarely, in the lower chalk, and in the grey chalk at Dover*. 

Teleosaurus. 

The family of extinct Crocodilians, which next remains to be noticed, is 

• Illustrations of the Geology of Sussex, 4to, 1827, p. 64. 



ON BRITISH FOSSIL REPTILES. 73 

characterized by a combination of a biconcave structure of the vertebrag, with 
long, narrow jaws, armed with slender, conical, sharp-pointed and equal teeth, 
adapted, liiie those of the existing Gavials, for the seizure and destruction 
of lishes. The species are separated into two genera, according to the 
difference of position in the external nostril, which, in the one called Teleo- 
suMviis, is terminal, or at the extremity of the upper jaw; in the other, 
called Steneosaurus, is a little behind and above the termination of the 
upper jaw. The species of both genera are confined to the oolitic division 
of the secondary rocks, and, since there were scarcely any Mammalia during 
that period, whilst the waters were abundantly stored with fishes, it might, a 
priori, have been expected, Dr, Buckland justly observes, "that if any Cro- 
codilian forms had then existed, they would most nearly have resembled the 
modern Gavial*." The modification in tlte structure of the vertebral column, 
and their complete mail of imbricated bony scutes, also indicate that the 
habits of the ancient Teleosauri and Steneosauri were more strictly marine 
than are those of the modern Gavials, and that their powers of swimming, of 
pursuing and overtaking their aquatic prey, were greater. 

The extinct reptile from which the characters of the genus Telcosaurus 
are derived, is one of the earliest of the evidences of ancient Reptilia which 
is recorded in a scientific publication. A brief description, and figures of an 
incomplete skeleton found in the lias (alum schale) of the Yorkshire coast, 
about half a mile from Whitby, were published by Messrs. Wooller and 
Chapman, in two separate communications, in the 50th volume of the Philo- 
sophical Transactions, 1758, (Pt. 2, jil. xxii. and xxx.). Their figures ex- 
hibit a contorted and incomplete vertebral column, about nine feet long, and 
a cranium slightly displaced, two feet nine inches in length. About ten ver- 
tebrae of the lumbar and sacral region of the trunk, and twelve vertebrae of 
the tail remain in place ; the cervical, dorsal, and middle coccygeal vertebrae 
were indicated only by their impressions ; and these are fewer in number 
than the vertebrae in the existing Crocodiles. The skull is reversed, pre- 
senting its basal surface to view : the single occipital condyle, the zygomatic 
arches, terminated behind by the strong tympanic bones, and the lai'ge convex 
articular surface in each of these, for the lower jaw, placed in the same trans- 
verse line as the occipital condyle, are all recognizable. The skull appears to 
contract gradually to a pointed muzzle, but in reality to the base of a long 
and slender maxillary beak. In the remaining basal or posterior portions of 
the jaws, the sockets of the teeth are seen separated by intervals of about 
nine lines ; in some of these there are pointed conical teeth, which cross al- 
ternately those of the opposite jaw. The teeth are covered with polished 
enamel f. 

Each of the vertebrae is three inches in length. Near the pelvic region, the 
.shaft of the femur, including the head, was exposed, measuring between 
three and four inches in length. A few fragments of ribs were found near 
the dorsal vertebrae. The authors of the papers just analysed perceived suf- 
ficient resemblance between their fossil and the skeleton of the Crocodile to 
refer it to that family of reptiles + ; but their figures and descriptions gave rise 
to various opinions respecting the affinities of the Whitby fossil in the writings 

* Bridge-water Treatise, vol. i. p. 250. 

t Cuvier truly states, " Ellcs n'ont pas cte decrites particiilicrement, et il est impossible 
de juRcr de Icurs caractcrcs par la gravure." — Oss. Fbss. 183G, ix. 225. 

X Captain Chapman says, " It seems to have been an alligator;" (/. e., p. 691.) and Mr. 
Wooller thinks that " it resembles in every respect the Gangetic Gavial." It will be shown, 
however, that the fossil really differs more from the Gavial than the Gavial does from any 
other exiatiug Crocodilian, 



74 REPORT — 1841. 

of subsequent naturalists and anatomists. Camper, for example, pronounced 
it to be a whale, perhaps meaning a dolphin, foi-, as Cuvier remarks, the pre- 
sence of teeth in both jaws at once proves the fossil not to belong to the 
Balsenas, which have no teeth, nor to the Physeters, which have (conspicuous) 
teeth only in the lower jaw. Faujas adopted Camper's opinion, referring the 
fossil to the genus Physeter, and adding some reasons which are contradicted 
by the descriptions given by both Chapman and WooUer. Cuvier, in the first 
edition of his ' Ossemens Fossiles,' after refuting the opinion of Faujas, says, 
" La verite, ainsi que nous le verrons, est que c'etoit reellement un crocodile." 
The subsequent analysis, to which Cuvier here refers, led him in 1812 to 
the conclusion that it belonged to the genus of Crocodiles, and was most pro- 
bably identical in species with the Crocodile of Honfleur. 

In 1836, however, when so many new and singular genera, allied to the 
Crocodilian family, had been added to the catalogues of Paleontology, 
chiefly by the labours and discoveries of English anatomists and geologists, 
Cuvier expresses his opinion on the fossil described by Wooller and Chapman 
with more caution. He says, " II reste maintenant a savoir si c'est un croco- 
dile, ou I'un de ces nouveaux genres decouverts dans les memos bancs. Les 
OS des extremites y sont trop incomplets, et la tete n'y est pas represente 
avec assez de details pour decider la question ; mais les vertebres me parais- 
sent plus longues, relativement a leur diametre, que dans les nouveaux genres, 
et plus semblables par ce caractere a celles des Crocodiles. Ceux qui retrou- 
veront I'original, s'il existe encore, pourront seuls nous apprendre si les autres 
caracteres repondent a celui-la." 

I have made inquiry at the British Museum, to Avhich the collections 
formerly belonging to the Royal Society were transferred, but no specimen 
corresponding with the account and figures given by the Whitby naturalists 
exists in that collection. 

A second specimen of a long and slender-nosed Crocodilian, was obtained 
from the lias near Whitby, between Staiths and Runswick, in the year 1791*; 
and a more perfect skeleton was discovered in the alum shale of the lias for- 
mation at Saltwick, near Whitby, in 1824. Both these specimens so closely 
resemble the older fossil in all the points in which a comparison can be esta- 
blished, as to dissipate the remaining doubts as to the nature and affinities of 
the specimen from the same locality, described in the Philosophical Trans- 
actions for 1758. The skeleton, discovered in 1824, is figured in Young and 
Bird's 'Geological Survey of the Yorkshire Coast', 2nd edit. 1828, pi. xvi. 
fig. 1. p. 287, and in Dr. Buckland's ' Bridgewater Treatise,' vol. ii. pi. xxv. 
It is now preserved in the museum at Whitby, where I have closely exa- 
mined it. In this specimen are preserved the cranium, wanting the snout, the 
whole vertebral column, the ribs, and the principal parts of the four extremi- 
ties, together with the dorsal, and part of the ventral series of dermal bones. 
The entire length of the skeleton, following the curvature of the spine, is 
fifteen feet six inches, to which may be added two feet six inches for the lost 
snout. The cranium posteriorly is broad, depressed, and square-shaped : it 
begins to contract anterior to the orbits, and gradually assumes the form of 
the narrow depressed snout ; the converging sides of the maxillae are concave 
outwardly. The zygomatic spaces are quadrilateral, longer in the axis of 
the skull than transversely ; the orbits are subcircular ; they look upwards 
and slightly outwards ; their margins are not raised, and their interspace is 
slightly concave. The parietal bone is relatively longer than in the Gavial, 
.and sends up a longitudinal median crest, from the posterior part of which 

* See History of Whitby, vol. ii. pp. 779, 780. 



ON BRITISH FOSSIL REPTILES. 75 

a strong process extends on each side outwards, and curves slightly backwards 
parallel with the ex-occipitals, to join the mastoid and tympanic bones, the 
latter of which expands as it descends to form the joint for the lower jaw. 

Feet. In. Lines. 

Breadth of posterior part of skull 100 

Length of parietal crest 060 

Breadth of the interorbital space 032 

Antero-posterior diameter of the middle of tympanic pedicle 2 5 

Vertical diameter of orbit 020 

Antero-posterior of orbit 030 

From lower margin of orbit to alveolar border 13 

From these dimensions it may be calculated that the entire length of the skull 
must have exceeded 4 feet 6 inches. 

The skull of one of the Caen Teleosauri measures 3 feet 4 inches, whence 
Cuvier calculates the entire length of the animal at near 15 feet. The Whitby 
Teleosaur agrees with the Caen species, and differs from the Gavial in the 
following particulars : the anterior frontal is less extended upon the cheek ; 
the lachrymal is much more extended, and is larger at its base; the jugal 
bone is more slender. The posterior fi'ontal, which separates the temporal 
from the orbital cavities, is much longer and narrower. The parietal and oc- 
cipital crests each form a thin trenchant plate, and are not flattened above. 
The mastoidean angle is not uninterruptedly united with the back part of 
the articular process of the tympanic, it is separated from it by a large de- 
pression, which is overarched by a trenchant crest belonging to the ex-occi- 
pital. The mastoidean bone has a concavity at its descending part, of which 
there is no trace in the Gavial. The indentation between the articular pro- 
cess of the tympanic, and the tuberosity of the basi-occipital is much smaller 
than in the Gavial, and the basilar tuberosity projects downwards in a less 
degree. The pterygoid ala is not expanded externally, as in all Crocodiles, 
but is contracted by a large fissure, at the part where it goes to unite itself 
to the bone ; the orbital margin of the malar is not raised, and does not leave 
behind it a deep fissure as in the Gavial. The malar does not rise to join the 
posterior frontal bone; but, on the contrary, the frontal descends to join the 
malar at the external margin of the orbit. The vacuity between the orbit and 
the anterior part of the tympanum is much elongated in the fossil, and occu- 
pies four-fifths of the temporal fossa ; the anterior part of this fossa is narrow 
and acute. The columella or ossicle of the ear is cylindrical, and much larger 
in proportion than in any known Crocodile or other reptile. 

Cuvier calculates the number of teeth in the Teleosaurus Cadomensis to be 

180, viz. '-f^. 

The Teleosaurus Chcqmmnni has at least 140 teeth. 

The Gavial has 112, or ^|5ii- 

The teeth of the Whitby Teleosaur are as slender and sharp-pointed, but 
not so compressed, as in the Gavial ; they correspond with those of the Caen 
Teleosaur, and equally illustrate the dental characters usually attributed to 
the present extinct genus*. 

The Whitby Teleosaur differs f>-om the Caen Teleosaur, as does the 

* M. H. V. Meyer refers to the genus Teleosaurus (Palicologica, p. 115) tlie thick obtuse 
teeth of the Wealden or Sussex Crocodile figured by Dr. Mantell in his ' Illustrations of the 
GeologN- of Sussex,' at pi. v. figs. 1, 2, 7, 9, 10, and 12. These teeth, however, belong to 
Goniopholis, as docs also the scute figured in pi. vi. fig. 8 ; and they are accompanied with 
deviations from the characters of Teleosaurus in the skeleton as striking as those which are 
manifested in their own robust and obtuse figure. 



76 REPORT — 1841. 

Monheim Teleosaur*, in having the upper temporal fossae longer in propor- 
tion to their breadth ; but it differs from the Teleosaurs of both Caen and 
Monheim in the more equal size of the teeth, and from the Monheim species 
in the greater number of teeth, the Teleosaurus prisons having at most 
2g_2() = 106. The median frontal in the Wliitby Teleosaur is slightly con- 
cave : in the Caen species it is flat. Tlie basi-occipital is perforated by the 
common terminal canal of the Eustachian tube close to the junction with the 
sphenoid, and, on eacli side of the hole, it expands into a rough tuberosity. 
The body of the sphenoid is compressed, characterized by tM'o processes or 
narrow ridges, continued one from each side of the middle of the sphenoid 
obliquely backwards. The pterygoid bones are relatively smaller than in the 
Gavial. The palatine bones are more extended posteriorly, and articulate 
with the transverse bones. The posterior apertures of the nasal canals are 
placed more forwards upon the base of the skull than in existing Crocodiles. 

Vertebral Column. — The number of vertebraj in the true Crocodiles of the 
present period rarely exceeds sixty, which is the number originally assigned 
by iElian-j- to the spinal column of the Crocodile of the Nile. Cuvier gene- 
rally found 7 cervical, 12 dorsal, 5 lumbar, 2 sacral, and 34 caudal vertebraj. 

In the Crocodilus acutits a thirteenth pair of ribs is occasionally developed, 
and, according to Plumier, it has two additional caudal vertebrae. 

The Alligator (^Alligator Lticius) has sixty-eight vertebrae, the additional 
ones being in the caudal region. 

The Gavial has sixty-seven vertebrae, disposed as follows: — 7 cervical, 13 
dorsal, 4 lumbar, 2 sacral, and 41 caudal vertebrae. 

The very perfect specimen in the Whitby Museum displays the number 
of the vertebrae through the whole spinal column, and establishes another 
difference between the Teleosaur and the Gavial, the former having a num- 
ber of vertebra intermediate between the Crocodiles and Gavials, viz. 64, 
with a special peculiarity in the excess of costal vertebrae, as the following 
formula indicates, viz. 7 cervical, 16 dorsal, 3 lumbar, 2 sacral, 36 caudal. 

In all sub-genera of existing Crocodiles, as in the extinct tertiary species, 
the hind surface of the vertebra is convex, the fore surface concave, except 
in the atlas and the two sacral vertebrae. 

Cuvier, wlio had the opportunity of seeing only the annular part (neura- 
pophyses) of the cervical vertebrae of the Caen Teleosaur, regrets his in- 
ability to state Avhether either of the articular extremities of the centrum 
were convex, or which of them %. The Whitby Teleosaur decides this ques- 
tion, and shows that both articular extremities of the vertebrae are slightly 
concave in the cervical as in the rest of the vertebral series. 

The atlas in the Teleosaur corresponds essentially with that of the Croco- 
diles, as is shown by the three main component parts of this bone, from a 
Whitby Teleosaur in Lord Enniskillen's collection. The body or centrum 
is a transverse quadrilateral piece, smooth and convex below, narrowing like 
an inverted wedge above, with six articular facets, viz. a concavity in front 
for the occipital condyle, a flat rougher surface on each side of the upper 
parte for the attachment of the neurapophyses ; a posterior facet for the an- 
terior part of the detached odontoid element of the axis ; and the small sur- 
face on each lateral, posterior and inferior angle for the atlantal ribs. The 
neurapophyses are pyramidal processes, with their apices curved towards 
each other ; they are relatively smaller in proportion to the centrum than in 
the Crocodiles. 

* Crocodilus prisons , Soemmerring. 

t De Natura Animaliuni, lib. x. sect, xxi, Jacob's Ed., 8vo, vol. i. p. 228. 

t Ossem. Fossiles, 4to, 1824, torn. v. pt, ii. p. 137. 



ON BRITISH FOSSIL REPTILES. 77 

The general anterior concavity for the reception of the occipital tubercle 
is formed at its circumference by the centrum and neurapophyses of the 
atlas, and at its middle by the anterior detached odontoid epiphysis of the 
axis, which is here evidently the analogue of the so-called atlas in the Ich- 
thyosaurus, the true body of the atlas in the Teleosaur representing the first 
inverted wedge-shaped bone in the Ichthyosaur. The spine of the atlas is 
a large strong oblong piece, articulated with the neurapophyses of the atlas, 
and partly overlapping those of the axis. 

The cervical vertebrae have strong transverse processes developed one 
from each side of the centrum, and one from the base of each neurapophysis. 
The posterior articular processes look obliquely downwards and outwards, 
the anterior ones obliquely upwards and inwards. The spinous process is 
compressed, its base coequal with the whole antero-posterior extent of the 
neurapophysis ; its height equal to the distance from its base to the upper 
transverse process; it inclines slightly backwards, and is slightly rounded 
off at the summit. The cervical rib is bifurcate at its vertebral end, the 
tubercle being as long as the head and neck ; its distal end is expanded into 
the hatchet shape, the posterior angle being most produced, and overlap- 
ping the costal process of the next vertebra behind. The same mechanism 
for fixing and strengthening the neck thus existed for the advantage of the 
ancient marine Crocodiles, as we find in those of the existing epoch. 

In the dorsal region the ribs exchange the hatchet for the ordinary length- 
ened form, and soon begin to lose the head and neck, as in existing Croco- 
diles ; after the fifth they no longer articulate with the central element, but 
only to the transverse process of the neurapophysis, which increases in antero- 
posterior extent and thickness, and pi-esents an oblique notch at its anterior 
angle, for the reception of the tubercle, now the only head of the rib. The 
number of the dorsal ribs exceeds that of any existing Crocodilian, being, 
as above indicated, 16 pairs. The spinous process is proportionally strong ; 
in the Whitby specimen it measures in most of the dorsal vertebrae 2 inches 
in antero-posterior extent, and seven lines in transverse diameter or thick- 
ness : the height of these spines seems not to have much exceeded that of 
the cervical spines, but they are more truncated at the summit. 

A posterior dorsal or lumbar vertebra of a Teleosaur from the Whitby lias, 
in the collection of Mr. Ripley, corresponds with the vertebral characters of 
Telcosaurus in the slight concavity and circular contour of the terminal arti- 
cular surfaces of the body, and in the great antero-posterior extent of the 
spinous processes ; but that of the transverse process does not exceed one- 
half the length of the body of the vertebra, which is 2 inches 6 lines. The 
transverse process is supported by two short obtuse slightly-developed ridges, 
which rise from the upper part of the side of the body, as far apart as to 
include one-third of the length of the body between them, and converge to 
the under part of tlie transverse process ; a similar ridge extends from the 
upper part of the posterior end of the transverse process obliquely backwards 
to the base of the posterior articular process. The neural arch is anchylosed 
to the centrum in this vertebra. The supporting buttresses of the transverse 
processes are not described by Cuvier in the dorsal vertebra; of the Ca<?n 
Teleosaur ; nor have I met with any dorsal or lumbar vertebras of the Whitby 
species, except the present, that was sufficiently perfect to exhibit tiiis cha- 
racter; it may, however, be constant and characteristic of the genus. It 
faintly indicates one of the most striking characters of the vertebrje of the 
Slreptospondylus. The anterior and posterior margins of the spinous pro- 
cess are slightly excavated, and thus retain a character which is transitory in 
the Crocodile, and peculiar to an early period of its existence. 



78 REPORT 1841. 

The transverse processes of the two sacral vertebrae are tliick, strong and 
expanded at their extremities. 

The bodies of all the vertebrce are compressed laterally, and concave antero- 
posteriorly at the sides ; but this character is more strongly marked in the 
anterior caudal vertebrae, which are flattened along the inferior surface ; these 
vertebrae in the Whitby specimen were 2 inches 8 lines in length. The 
transverse processes are longer, but narrower antero-posteriorly than in the 
lumbar or dorsal vertebrae. The haemapophyses are united at their peripheral 
end, forming chevron bones, but are detached at their central ends, which 
are articulated, as in recent Crocodiles, with the interspaces of the vertebral 
centres. The caudal vertebrae progressively diminish in every diameter, 
save length, from the middle to near the end of the tail ; the terminal vei'tebrse 
are shorter than the rest. 

The sternum and sternal ribs closely agree with the ordinary Crocodilian 
type. I have not yet seen a specimen of the abdominal sternal ribs. 

Pectoral extremities. — The scapula and coracoid resemble, in general form, 
those of the Crocodile, but are relatively smaller, in correspondence with the 
smaller size of the anterior extremities. The scajjula, for example, is only 
one-third the length of the femur; it is straighter than that of the Crocodile ; 
both margins are nearly equally concave, instead of the anterior one being 
convex : the humeral end is less expanded, and is more obliquely truncated. 
The coracoid is longer than the scapula, instead of being, as in the Crocodiles, 
shorter : this probably depends upon the breadth of the fore part of the body, 
which regulates the extent of the coracoid, while the proportions of the 
scapula more exclusively depend upon the development of the pectoral ex- 
tremity. The coracoid of the Teleosaur differs also from that of the Croco- 
dile in the greater expansion of its humeral end, the more transvei'se position 
of its sternal convex extremity, and a nearer approach to parallelism in the 
direction of the two lateral margins. 

In the Whitby Teleosaur, discovered in 1824, the humerus of the right 
anterior extremity, and the humerus and bones of the fore-arm of the left 
are preserved nearly in their proper relative positions. The humerus is 
shorter in proportion than in the Crocodiles, its length scarcely exceeds the 
antero-posterior diameter of two of the cervical vertebrae. The antibrachial 
bones are still more curtailed in their proportions ; the longest bone, or ulna, 
being not quite half the length of the humerus. 

No portions of the carpal or other bones of the paddle are preserved, but 
the presence of the antibrachial bones, distinct from each other, and of the 
ordinary form and breadth at the distal end, forbid our supposing them to 
have been naturally deficient or of abortive proportions in the Teleosaurus. 
The humerus, radius and ulna must have existed for a purpose, and that pur- 
pose, we may conclude, from the modifications for an aquatic life in the rest 
of the skeleton, to have been the support and movement of a palmated manus ; 
an organ which would be of great use in turning and regulating the course 
of the swimmer, and in bringing the long and slender snout, with the terminal 
nostrils, to the surface. The fore-paddles were doubtless much smaller than 
in ordinary Crocodiles, and this difference of proportion related both to the 
less frequent resorting of the Teleosaur to dry land, and to the light and 
slender character of its jaws and teeth, and the consequent diminution of the 
weight of its head. 

Pelvic extremity. — The pelvis of the Teleosaur was attached, as in the 
Crocodile, to the thickened and expanded transverse processes of two sacral 
vertebrae. These processes are stronger in the vertical direction, and inter- 
cept a relatively smaller and more regularly elliptical space than in the exist- 



ON BRITISH FOSSIL REPTILES. 79 

ing Crocodiles ; the anterior one appears not to have been so much expanded 
in the antero-posterior direction. The iliac bone seems to have been shorter 
in the antero-posterior diameter, but longer, as measured transversely to the 
axis of the trunk, and thus to have made a slight approach to its character- 
istic form in the Enaliosaurs. 

Both the ischium and pubis are relatively more expanded than in the 
Gavial. The pelvic extremities are preserved in the Whitby specimen in 
nearly their true relative positions ; but the right is thrown directly over the 
left. The femur presents the usual Crocodilian form., but is relatively more 
slender than in the existing Crocodilians ; it is slightly twisted, and bent in 
two directions. Its proximal end is expanded, compressed with a regular 
convex curve, describing a semicircle ; the trochanter is represented by a ridge 
which gradually subsides, and is lost upon the surface of the shaft. This is 
nearly cylindrical at the upper part, but is produced at the anterior or convex 
side along the distal half in the form of an obtuse ridge. The condyles are 
very feebly indicated. In the Whitby specimen of 1824, 

Feet. In. Lines. 

The length of the femur is 1 3 3 

The breadth of proximal end of ditto . . 2 10 
The diameter of middle of shaft .... 1 4 
Both the tibia and fibula are subcompressed towards their distal end : the 
length of each bone is 8 inches. The shaft of the fibula is nearly as thick 
as that of the tibia. The bones of the leg of the Teleosauriis resemble 
those of the Aelodon in their relative shortness as compared with the femur. 
In these, and probably in other ancient Crocodiles with biconcave vertebrae 
and marine habits, the tibia is little more than half the length of the femur ; 
while in recent Gavials it is two-thirds that length. There are five tarsal 
bones, two in the proximal and three in the distal row, as in the Gavial ; but 
they are of more equal size ; the two proximal bones being by no means so 
disproportionately large. All the long bones have distinct medullary cavities, 
and these are even present in the metatarsals. In the Whitby specimen, 
The length of the middle metatarsal is ... . 6 inches. 

The breadth of its proximal end 10 lines. 

The breadth of its distal end 6 lines. 

The ungual phalanges are depressed, smooth and convex above, rounded at 
the end. 

Dermal armour. — The bony dermal scutes of the Teleosaur were regularly 
disposed like those of existing Crocodiles, in both longitudinal and transverse 
series ; the posterior margin of one scute covered the base of the succeed- 
ing scute *, and they slightly overlapped each other laterally. 

Cuvier states that one of the fossils of the Teleosauriis Cadomensis presents 
all those of one side in their natural situation, exhibiting, in the part of the 
body included between the first dorsal and the beginning of the tail, fifteen 
or sixteen transverse rows, containing five scutes on each side ; so that there 
were at least ten longitudinal rows of these dermal bones. 

The scutes are arranged in the same manner and number, at least as regards 
the transverse rows, in the Whitby Teleosaur ; these rows being indicated by 
the large dorsal scutes still occupying their natural position in an uninter- 
rupted line along the back ; they are twenty in number, and sixteen cover 
the vertebrae included between the last cervical and first caudal. 

The scutes of the Teleosaurus Chapmanni differ as much from those of the 
existing Gavials and Crocodiles, as do those of the Teleosaurus Cadomensis, 

* Cuv., /. c. p. 279. 



80 REPORT — 1841. 

being thicker, rectangular, and having the outer surface impressed with cir- 
cular pits or indentations from three to four lines in diameter, which are not 
confluent, but separated. 

The median dorsal scutes of the Whitby specimen are nearly square, 
having the longer diameter, about three inches and a half across, placed trans- 
verse to the axis of the body, and with the outer margin slightly rounded. 
Each of these scutes is traversed, as in the Teleosaurus priscus, by a longi- 
tudinal ridge, which is less developed than in the Gavials. The median dor- 
sal scutes of the Teleosauri Cadomensis and priscus appear to differ from 
those of the Teleosaurus Chapmanni in being more oblong transversely, and 
with the posterior and lateral margins rounded off. Cuvier does-pot allude 
to the cai'inated character of these plates in the Caen species. 

The lateral and ventral scutes of the Teleosaurus Chapmanni are more per.r- 
feet squares than those next the spine, but differ less in form and size fro.m 
them, than in the Caen Teleosaur. They are marked externally by the same 
impressed pattern, but are not carinated. The median abdominal scutes are 
not opposite but alternate ; their median margins are rounded ofl^, or slightly 
angular ; and, while the anterior part of that margin is overlapped by the 
posterior half of the opposite scute, in advance, the posterior half overlaps 
the succeeding scutum of the opposite side. The verticillate cuirass of these 
ancient Crocodiles is thus securely braced round the trunk by this inter- 
locking of the inferior extremities of each ring of scutes, whilst the imbri- 
cated arrangement would allow of a certain sliding motion of the rings upon 
each other sufficient for the expansion qf the chest in breathing. The scutes 
in the fine specimen in the Whitby Museum measure about five lines in 
thickness, but are thinned off at the edge. 

Having now detailed the anatomical particulars which a study of the mag- 
nificent and unique skeleton of the Teleosaurus, in the museum at Whitby, 
has enabled me to add to the previous descriptions, by Cuvier and other ana- 
tomists, of the osteological structure of this extinct Crocodilian genus, I next 
proceed to notice the principal examples of the same genus which are preserved 
in other collections of British Fossil Reptiles. 

The first of these is a fine skull of the same species of Teleosaurus, and 
from the same lias beds near Whitby, in the museum of Mr. Ripley of that 
town : — 

Feet. Inches. 

The length of the entire skull is 2 9 

From the angle to the beginning of the long symphysis of 

the lower jaw 1 3 

Breadth of the lower jaw at the posterior commencement 

of symphysis 2^ 

Breadth of the extremity of the lower jaw 1 

The extremity of the upper jaw well exhibits in this specimen the charac- 
teristic generic modification of its infundibuliform expansion, supporting the 
terminal nostrils, and resembling the extremity of the elephant's proboscis, 
wanting the digital process. 

This cranium also clearly exhibits the specific charactei's by which the 
Teleosaurus Chapmanni of the Yorkshire lias differs from the Teleosaums 
Cadomensis of the Caen oolite, viz. the greater antero-posterior extent of the 
upper temporal openings as compared with their transverse diameter in the 
Teleosaurus Chapmanni; the similar but slighter difference in the form of 
the orbits, the greater breadth of tiie interorbital space, which slightly ex- 
ceeds the transverse diameter of the orbit instead of falling short of that 
diameter, as in the Teleosaurus Cadomensis. 



ON BRITISH FOSSIL REPTILES. 81 

A cranium of the Teleosaurus Chapmanni, in the museum of the Philo- 
sophical Institution at York, and another in the museum at Scarborough, 
offer the same specific characters as the Whitby specimens. In the Scar- 
borough cranium the diameter of the orbit is 2 inches 3 lines, while that of 
the interorbital space is 2 inches 6 lines. 

In the museum of the Natural History Society at Lancaster there is a chain 
of five dorsal vertebrae of the Teleosaurus Chapmanni, from the Whitby lias, 
measuring 1 foot in length ; each vertebra is 2 inches 4 lines in length. A sec- 
tion of these vertebrae showed a small cavity in the centre of the cancellous 
structure of the body*. 

Teleosaurus Cadomensis. — Specimens of fragments of the jaw, teeth and 
vertebrae of this species have been discovered in the Bath oolite at Enslow, 
near Woodstock, and in the oolite at Stouesfield. 

Teleosaurus Cadomensis (var.). — Of this species, which is nearly allied to, 
if not identical with Cadomensis, I have examined a posterior cervical ver- 
tebra from the oolite near Chipping Norton, now in the collection of Mr. 
Kingdon of that town. The sides of the centrum are less compressed than in 
the Teleosaurus Chapmanni, and the articular extremities have a more cir- 
cular contour, the transverse exceeding the vertical diameter. There is no 
appearance of a ridge along the under surface : the transverse process of the 
centrum arises close to the neurapophysis. 

Inch. Lines. 

The length of this vertebra is 1 5 

Transverse diameter of centrum 1 3 

Vertical diameter of centrum 1 1^ 

Teleosaurus asthenodeirus. Nob. — If the cranium of this Saurian should 
correspond with the characters of the genus Teleosaurus which are exhibited 
by the vertebrae and scutes here described, a distinct species of this genus is 
very evidently indicated by them, characterized by the smaller size of the 
cervical ribs, and the consequently weaker structure of the neck. 

In the Oxford Museum are preserved two cervical vertebree and a dermal 
bone of this species, from the Kimmeridge clay at Shotover. The articular 
extremities and general form of the body of the vertebrae accord with the 
Teleosaurian type. 

Inches. Lines. 

The length of the centrum is 2 2 

Vertical diameter of articular end 1 6 

Transverse diameter of articular end 1 5 

Antero -posterior extent of lower transverse process 6 

This process arises near the lower surface of the centrum, about half an 
inch from the anterior extremity of the bone. It is separated about the same 
distance from the upper transverse process, which is continued from the base 
of the neurapophysis ; both the supports of the cervical rib are one-third 
smaller than the corresponding processes in the Teleosauri Chapmanni and 
Cadomensis, and are less extended from the sides of the vertebra. 

The dermal scute is devoid of a ridge ; one-half of the external surface is 
pitted with well-defined hemispherical depressions, separated from each other 
by about half their breadth, the smallest being nearest the margin : the other 
half of the scute is smooth, and indicates that it was overlapped by the ad- 

* I have much pleasure in expressing my thanks to S. Simpson, Esq., the Secretary of this 
excellent Institution, for the prompt acquiescence with my desire to have a section of these 
vertebra; made ; and likewise to Thos. Satterthwaite, Esq., a member of the Society, for an 
accurate drawing of the fossil. 

18-11. G 



82 ~ REPORT— 1841. 

joining scute, according to the characteristic disposition of this fish-like 
covering of the present extinct marine genus of Crocodilians. 

In the Hunterian Collection are two entire dorsal vertebrae, with part of a 
third, fractured through the middle of the body, and displaying a small can- 
cellated cavity tilled with calcareous spar, as in the Teleosaurus Chapmanni. 
These vertebrae present the slightly concave articular extremities, and the 
other characters of the genus Teleosaurus. The length of the centrum, 
measured along the under surface, is 2 inches 6 lines; vertical diameter of 
articular end 2 inches; transverse diameter 1 inch 10 lines; transverse dia- 
meter of the middle of the body 1 inch. Both the inferior and lateral sur- 
faces of the body are regularly concave, lengthwise ; and smooth, except 
near the expanded articular extremities, where they are striated in the axis of 
the vertebra. 

The antero-posterior extent of the transverse process is 1 inch 6 lines ; 
that of the base of the spinous process 1 inch 9 lines. The transverse dia- 
meter of the spinal canal 7 lines ; its vertical diameter ^\ lines. 

These vertebra are cemented together by a matrix, which closely resem- 
bles the gray Kimmeiidge clay : and a portion of a species of Pecten is at- 
tached, which is one of the characteristic fossils of the oolite group of secondaiy 
rocks, especially the Oxford clay. 

Steneosaurus. 

Ide Gavial d' Honjieiir, Cuv. 

Steneosaurus rostro-minor, Geoffroy. 

The generic name Steneosaurus, proposed by Geoffroy St. Hilaire for 
the Gavial-like Crocodilians with subterminal nostrils, but applied by him to 
species with vertebrae of two distinct systems, and altogether rejecte'd by M. 
Hermann von Meyer, I propose to retain for that section of the Geoffroyan 
genus, including the species with vertebrae subconcave at both extremities, as 
in the genus Teleosaurus. 

Remains of the genus Steneosaurus, thus defined, occur in the Kimme- 
ridge clay at Shotover, and in the great or middle oolite. 

I shall first describe a mutilated cranium from Shotover, preserved in the 
museum of Professor Buckland at Oxford. In this specimen the sides of 
the inter-temporal crest slope away, except at its anterior part, where it 
expands to one inch in breadth, and is convex : its longitudinal contour is 
slightly convex. The posterior boundary of the temporal fossa sinks below 
the level of the upper part of the cranium, and likewise terminates above in 
a sharp ridge, as in Teleosaurus. The ex-occipitals send out a transverse 
ridge, increasing in size to the mastoid process, below which there is a fora- 
men : the cranial canal is cylindrical. The ex-occipitals so completely sur- 
round the posterior aperture of the cranium, that when the basi-occipital is 
displaced it remains entire. This is not the case in the Teleosaurus. 

Steneosaurus. Teleosaurus Chapmanni. 

Inches. Lines. Inches. Lines. 

Breadth of posterior part of cranium 110 5 Q 
From lower margin of condyle to in- "1 . 

ter-temporal ridge J 

Length of temporal fossa 5 2 6 

Breadth of temporal fossa 5 2 

In the upper jaw the teeth are closer together and relatively larger: there are 
3 teeth in front of, and 27 behind, a short diastema : there is no groove along 
the inner side of the ramus of the jaw. In the lower jaw the post-articular 



ON BRITISH FOSSIL REPTILES. 83 

angle is equal in length to the transverse diameter of the articular surface, ap- 
proaching thus to Plesiosaurian proportions, whilst it is longer in the Gavial and 
in Teleosaurus. The articular surface is convex in the middle and concave on 
each side, as in the Teleosaurus, and not regularly concave, as in Gavial : the 
articular piece is continued more forwards, and is stronger upon the internal 
side of the i-amus. The depth of the ramus at the coronoid ridge is greater, and 
the coronoid ridge itself is higher : there is no interspace between the an- 
gular and surangular elements*. From the angle to the beginning of the 
symphysis of the jaw is 1 foot 9 inches, the depth of the jaw at the coronoid 
process is 4 inches. The nostrils are bounded by short intermaxillaries, 
each of which contains three teeth. Both intermaxillary and maxillary teeth 
are larger in proportion than in Teleosaurus. The maxillary teeth are ar- 
ranged closer together as they are placed further back. In a fragment of 
jaw containing three teeth, these are placed obliquely in sockets, from two 
to three lines apart. The fang is covered by a smooth white cement ; the 
crown with a black enamel, traversed by fine longitudinal, close-set, inter- 
rupted ridges, one on each side of the tooth, is stronger than the rest, and 
meeting, in the unworn teeth, upon an obtuse summit. 

In a fragment of a lower jaw of apparently the same species of Steneosaurus, 
in the Hunterian Collection, which includes 6 inches of the posterior com- 
mencement of the symphysis, the transverse diameter, at the junction of 
the rami, is 4 inches 3 lines : the middle of the posterior surface of the 
junction is excavated by a deep transversely elliptical depression. Both the 
upper and lower surfaces of this portion of jaw are flat, and the sides are 
nearly flat, and on right angles with the horizontal surfaces ; the intervening 
angles being rounded off". The inner border of the alveolar tract is higher 
than the outer. The inferior flattened surface is impressed with some small, 
irregular, longitudinal vascular grooves, but not with pits or foramina. Eight 
teeth are contained in an extent of the alveolar tract measuring 5^ inches. 
The diameter of the circular base of the crown of the tooth is from four to 
five lines. The matrix appears to be oolite ; the cavities in the crowns of 
the teeth are filled with white spar. 

Perhaps the most interesting fact which has resulted from an examination 
of the British fossils of the present genus is the size and form of the brain, 
as exhibited by an internal cast of the cranial cavity. 

In the museum of Professor Sedgwick there is a slab, in which the head 
of a Steneosaurus is imbedded, the upper part being exposed, from which a 
considerable part of the bony substance has been broken away, and, amongst 
the rest, the whole upper wall of the cranial cavity, exposing a tolerably per- 
fect cast of its interior, which represents the brain of the extinct reptile. 
This cast resembles the smooth convex cerebral lobes of the Crocodile, and a 
portion of the large optic lobes which lie posterior to them. The cerebrum 
is 1^ inch in breadth, and the whole of the brain represented by this cast is 
2 inches in length. The breadth of this head is 6-^ inches. The temporal 
openings form wide ellipses, 2 inches 9 lines in the long diameter : from the 
back of the cranium to the commencement of the narrow elongated jaws is 8 
inches ; from these proportions the length of the individual may be calculated 
at about 18 feet. 

* In the thin, long and slender jaws ascribed to the Poikilopleuron by M. Deslongchamps, 
the coronoid is not raised, and there is an oblong vacuity between the angular and suran- 
gular. 



g2 



84 REPORT — 1841. 

POIKILOPLEURON BUCKLANDI, Eudes-Deslongehamps. 

Nos. 1^ and — , in the Mantellian Collection, are the two moieties of a 
fossil caudal vertebra, fractured obliquely across the middle of the body, the 
lensth of which is to the breadth of its articular extremity as 3 to 2 : both 
extremities are slightly concave ; the body is gradually contracted from the 
two extremities towards the middle part ; bears a transverse process deve- 
loped from the posterior and upper part of its side, behind which there is a 
shallow groove ; has the neural arch anchylosed, without trace of suture, to 
nearly the whole of the longitudinal extent of its upper surface. The neural 
arch is provided with anterior and posterior oblique processes, and a broad 
and thin spine developed at its posterior part, and strongly inclined back- 
wards at its origin ; lastly, the vertebra has a large meduUaiy cavity in the 
centre of the body, filled, in the fossil, with spar. In all these particulars 
the Palaeontologist acquainted with the excellent description by M. Eudes- 
Deslongchamps of the Poikilopleuron Bucklandi, from the oolite at Caen, 
will not fail to recognise the distinctive characters of that species in the 
present fossil. It is attached to a mass of the common Wealden stone, which 
is quarried at Tilgate, and was associated with the bones of the Ignanodon. 

The length of the present vertebra is 3 inches 9 lines, or 9| centimeters ; 
that of the caudal vertebrae of the Poikilopleuron of Caen is about a deci- 
meter*. We may conclude, therefore, that the individual from the Caen 
oolite and that from the Wealden were of the same size, and, from this cor- 
respondence, it is most likely that the size — 25 French feet, which M. Des- 
longchamps assigns to the entire animal — is the common size of the species. 

The vertical diameter of the articular end of the body of the Wealden ver- 
tebra is 2 inches 3 lines (5J centimeters) ; the transverse diameter of the 
same part is 2 inches 2 lines (5^ centimeters) ; the transverse diameter of 
the middle contracted part of the body is 1 inch 4 lines (S-j centimeters). 
The external free surface of the vertebra is almost smooth, being faintly 
marked by fine striae. The form of the terminal surfaces of the centrum is 
a full ellipse, with its long diameter vertical. The longitudinal sulcus at the 
upper part of the side of the body is shallow, and slightly bent, with the con- 
vexity downwards ; the base of the transverse process is continued from the 
upper boundary of the groove, and extends along the posterior half of the 
upper and lateral part of the centrum, and upon the base of the neural arch, 
whicli is here wider than the centrum : the transverse process is broken off 
near its origin. The base of the neurapophysis or side of the neural arch 
leaves only a very small portion of the upper part of the centrum free at its 
anterior and posterior part, to form the hole for the transmission of the spinal 
nerve : the distinction between the present genus and the Cetiosaurus is 
well marked in this respect. The neurapophyses have a less vertical extent 
than in the corresponding vertebra of the Cetiosaurus, or even than in the 
Crocodile. From the upper part of the centrum to the upper edge of the 
anterior oblique process in a vertical line is only 1 inch, or about 2^ centi- 
meters. The base of the spinous process is not thickest at its posterior 
margin, but gradually expands transversely as it extends forwards, and then, 
at a distance of 10 lines from its posterior part, it quickly contracts to a very 
thin plate, which is continued forwards to the conical depression at the inter- 
space of the origin of the anterior oblique processes. The upper jiart of the 
spine is broken away, but the remaining base has the same backward inclina- 
tion as in the Caen Poikilopletiron. 

From the size and position of the transverse process, the Tilgate vertebra 

* " Nos vertebres ont chacune en^■iron un decimetre de long." — Deslongchamps, I. c, p. 53. 



ON BRITISH FOSSIL REPTILES. 85 

corresponds with the second or third of the first series of caudal vertebraa of 
the Caen PoUnlopleuron figured by M. Deslongchanips. There is one cha- 
racter in the Wealden vertebra whicli is not mentioned in M. Deslong- 
chanips' description of the Caen species, viz. a longitudinal sulcus at the 
middle of the under surface of the bodj^ of the vertebra, at least at its ante- 
rior half: the sulcus is not deep, and is 1 centimeter or 4 lines in breadtli. 
The extremity of the under surface seems to be obliquely leveled off to form 
a single haemapophysial surface. From this structure it might have been in- 
ferred that the haemapophyses, which by their union form the chevron bone, 
were closely approximated, if not confluent at their bases, as in the Iguano- 
don ; the Caen specimen, in which many of the chevron bones are preserved, 
proves this to have been the case. The fortunate fracture Avhich demonstrates 
the peculiarly large medullary cavity in the centre of the vertebral body, 
gives the best proof that could be required of the generic identity of the 
Wealden vertebra with tl-.e Caen Poihilopleuron ; and the absence of that 
cavity in the vertebrae of the Megalosaurus, which I have determined by a 
section of one of the caudal vertebrae, establishes the distinction between that 
genus and the Poihilopleuron. 

In the form of its sub-biconcave vertebrae, and the simplicity of their 
neural arch as compared with the Streptospondylus and the Dinosauricms, 
the Poihilopleuron manifests its closer affinity to the Ccelospondylian Croco- 
diles. It agrees with the Teleosaurus in the comparative shortness of the 
fore legs ; the mode of articulation of the vertebral ribs appears to be the 
same, and there is no evidence that it differs in the structure of the ab- 
dominal ribs. 

The number of caudal vertebrae would appear to be greater ; but I know 
not in what material respect the Poihilopleuron resembles the Lizard tribe 
more closely than does the Teleosaurus, unless it should be proved to have 
five toes on the hind foot, and to Avant the dermal armour. Subsequent dis- 
coveries may prove it to belong, like the Megalosaurus, to the Dinosaurian 
order ; but as the Poihilopleuron is at present known, it seems to have most 
claim to be received into the Codospondylian family of the Crocodilian 
order, and perhaps has the closest affinity in that family to the Crocodilus 
Bollensis, Jaeger (^Macrospondylits, H. v. Meyer). 

To the genus Poihilopleuron it is most probable that the specimen 

No. ^^ in the Mantellian Collection belongs, as it agrees in size, in texture, 
and especially in the character of the external surface with the caudal ver- 
tebra last described. As it consists of the annular part or neural arch only, 
the test of the medullary cavity of the body cannot be applied. It belongs to 
one of the anterior dorsal vertebrae, and is distinguished by well-marked and 
peculiar characters from the corresponding vertebrae of the Iguanodon, Me- 
galosaurus, Hylaosaurus, Cetiosaurus, and Streptospondylus ; and in the chief 
of these differences it approximates to the sub-biconcave Crocodilian type of 
vertebrae. As only the caudal vertebrae of the Poihilopleuron appear to have 
been hitherto discovered, I cannot avail myself of the aid, in the determina- 
tion of the present fossil, which the able descriptions of M. Deslongchanips 
afforded in reference to the preceding one ; there remains, therefore, to record 
the characters of the present fragment of a dorsal vertebra, in order that they 
may be compared with more perfect ones from the oolite of 3Ialadrerie near 
Caen, in the event of the remainder of the vertebral column of the Poihilo- 
pleuron ever falling into the hands of the Palaeontologist. 

The present fossil is imbedded in the ferruginous sand of the Tilgate strata ; 
its antero-posterior diameter from the extremity of the anterior to that of the 
posterior oblique process, is 5 inches 4 lines. 



86 REPORT — 1841. 

The neurapophyses, instead of rising and expanding to form a broad plat- 
form to support the spinous process, as in the Dinosaurian vertebrae of the 
Wealden, converge rapidly above the spinal canal, and support the spinous 
and transverse processes by a longitudinal plate not more than from 3 to 6 
lines in transverse thickness ; from each side of this plate a horizontal, flat, 
broad, lamelliform transverse process, supported below by a subvertical tri- 
angular plate, extends outwards and a little upwards ; and a broad, thin, and 
moderately high spinous process arises, in a peculiar manner, by two laminae, 
from the whole antero-posterior extent of the ridge-like summit of the neural 
arch. The fossil is broken in two ; a portion of the centrum adheres to the 
anterior part of the neural arch, demonstrating the anchylosis of the two 
parts without trace of suture. In this respect the fossil agrees with Poikilo- 
pleuron and differs from Iguanodon, in which the neural arch is anchylosed 
with the centrum, but evident traces of the suture remain, at least in the 
dorsal vertebrae. The anterior part of the side of- the centrum is impressed 
by a large surface for the head of the rib ; the surface is concave in the axis of 
the vertebra, convex vertically, and is bounded above by a well-defined ridge. 

The anterior oblique processes support flat articular surfaces of an ellip- 
tical form, 16 lines by 9 lines, looking upwards and inwards, their lower edges 
converging at an angle of 50°. These edges are separated from each other 
by a fissure 3|- lines broad, continued to the base of the anterior oblique pro- 
cesses. In the Iguanodon the corresponding surfaces incline to each other 
at a right angle, and the lower margins of the processes are united by a con- 
tinuous tract of bone. The present fossil, in the above-cited particular, re- 
sembles more the Cetiosaurus. Each anterior articular surface is supported 
by a stout process convex externally, inclining forwards and slightly expand- 
ing, so as to overhang and extend in a slight degree beyond the anterior end 
of the centrum : these processes are relatively lower than in the IguuTiodon, 
in which also they do not extend beyond the centrum : the present fossil, in 
differing in these two respects from the Iguanodon, indicates characters which 
are exaggerated in the caudal vertebrae of the Iguanodon. A deep and 
narrow excavation commences immediately behind the upper and posterior 
origins of the anterior oblique processes, and is continued backwards, in- 
creasing in vertical extent, deep into the anterior part of the base of the 
spinous process. Immediately behind the columnar portion of the anterior 
oblique process a deep and wide conical cavity sinks, as it were, into the 
neurapophysis, undermining the anterior part of the base of the transverse 
process, and dividing the anterior oblique process from the supporting plate 
of the transverse process. 

The transverse process commences from the summit of the neurapophysis 
immediately exterior to the anterior part of the base of the spinous process, 
by a ridge which is continued backwards from the upper and outer margin 
of the anterior oblique process, in a gentle curve outwards and slightly up- 
wards. The posterior margin of the base of the transverse process is not 
continued, in like manner, into the posterior oblique process, but terminates 
or subsides into a ridge above, and separated from that process by a wide 
groove. 

The bases of the two transverse processes are only separated from each 
other, owing to the modification of the neural arch above mentioned, by a 
thickness of bone not exceeding 4 lines : the interspace of the origins of the 
two transverse processes in a corresponding vertebra of the Iguanodon 
measures 4 inches ; the length of the base of the neural arch being the same 
in the vertebrae compared. 

The antero-posterior extent of the base of the transverse process in this 



ON BRITISH FOSSIL REPTILES. 87 

(presumed) vertebra of the Poikilopleuron is 2 inches 2 lines. The length 
of the transverse process is 4 inches. The vertical diameter, or thickness of 
the transverse process, where unsupported, is from 2 to 3 lines. It is obvious, 
therefore, that this long, thin, lamelliform plate of bone must need further 
support, in order to sustain the rib which is appended by its tubercle to the 
extremity ; and the requisite strength is here given precisely as the carpenter 
supports a shelf by a bracket. The bracket-like process is a vertical tri- 
angular plate of bone, the breadth or depth of which, at its origin, is 1 inch 
4 lines, and which gradually diminishes in depth and increases in thickness 
as it extends along the middle of the under part of the transverse process, 
until it is finally lost near the extremity of the process, which here has ex- 
changed its lamellar for a prismatic form, terminating in the obtuse extremity 
against which the tubercle of the rib abutted. The supporting bracket is 
not quite vertical, but inclines a little forwards, and behind it there is a deep 
angular fossa. The posterior oblique processes diverge from each other and 
from the neural arch immediately above the posterior extremity of the spinal 
canal : each articular surface, which is directed downwards and outwards, 
forms, as it were, the base of a posterior root of the spinous process, which is 
convex externally, diminishing in breadth as it converges to meet its fellow 
at a very acute angle above a deep fissure extending forwards into the sub- 
stance of the base of the spine, similarly to the fissure before described as 
extending backwards from the opposite part of the spine into its substance. 
As far as I could detach the matrix, these fissures extended so that they seem 
to communicate, and the neural arch to be perforated by two longitudinal 
passages, one for the spinal chord, and the other, running above and parallel 
with the former, througli the base of the spinous process. This process is 
thus partially separated at its base into two laminte, and presents a structure 
which almost realizes Prof. Geoffroy's theoretical idea of the essential nature 
of a spinous process, viz. that it consists of two elementary laminae, which in 
fishes are superimposed one on the other, but in other Vertebrates are placed 
in juxtaposition. 

The anterior parts of each spinal plate are thickened and rounded, like 
those behind, and extend to the origins of the anterior oblique processes. The 
diameter of this remarkable spinal fissure is from 4 to 3 lines. It is present in 
an inferior degree in the Teleosaurus, but not in the vertebrae of the Igua- 
nodon, Megalosaurus, or other Dinosauria. 

The base of the spinous process in this (presumed) Poikilopleuron's ver- 
tebra, instead of descending from behind forwards in a graceful curve, as in 
the Dinosaurs, forms a straight and almost horizontal line, 3 inches in extent : 
the spine maintains the same breadth to its summit, which is truncated rather 
obliquely; its height is 4 inches 9 lines, measured from the upper end of the 
posterior oblique processes ; it is thickened and rounded at its truncate sum- 
mit. The heiglit of the spine of a corresponding vertebra of the Iguanodon, 
with a centrum of the same length, is 9 inches. Thus the present vertebra 
more resembles, in the form and proportions of its spinous process, as in other 
characters, the vertebrae of the Crocodilians. 

The posterior part of the neural arch, with the spinous process of the ver- 
tebra here described, is figured in Dr. Mantell's ' Illustrations of the Geology 
of Sussex,' pi. xii. fig. 1, as the ' Lumbar Vertebra of the Iguanodon.' It is 
unquestionably not a lumbar vertebra ; and if it does not belong to the Poi- 
kilopleuron, it indicates an unknown genus of Crocodilians. 

In a collection of fossils belonging to S. H. Christie, Esq., from the sub- 
merged Wealden beds near the Isle of Wight, there is one half of the cen- 
trum of a dorsal vertebra from Brook Bay, which agrees in size, in the form 



88 REPORT — 1841. 

of the articular extremity, in the degree of median constriction, and, espe- 
cially, in the large size of the medullary cavity at the middle of the bone, 
with the vertebral characters of the Poikilopleuro?i. 

Streptospondvlus, H. von Meyer. 
Steneosaurus rostro-mcijor, GeofFroy. — 1 re Gavial d' Honjleur, Cuv. (vertebrce.) 

I am not aware that remains of this Crocodilian genus have hitherto been 
recognised in any of the British strata. The very characteristic vertebrae 
and jaws, of which the singular generic modifications Avere first described by 
Cuvier,* were found in the Oxford clay formation at Honfleur, and in the 
Kimmeridge clay at Havre. M. Hermann von Meyer likewise cites the lias 
of Altdorf as a depository of the fossil bones of this genusf . 

The distinguishing vertebral characters are a ball and socket articulation 
of the bodies of the vertebrae ; but the positions of the ball and cavity are 
the reverse of those in the existing Crocodiles, the convexity being on the 
anterior part of the vertebra, and the concavity directed backwards. In the 
anterior vertebrae, which have the ribs articulated with the body, there is a 
deep pit behind the costal articular surface ; the transverse process rises by 
four salient ridges, one from each oblique process, and the two inferior and 
principal ones from the base of the neurapophysis ; these ridges converge at 
an acute angle as they ascend, and meet at the under part of the transverse 
process, so as to include a triangular space, which is deeply concave. A 
third salient ridge ascends from the fore part of the base of the neurapophy- 
sis to the anterior oblique process, nearly parallel with the posterior of the 
two last-mentioned ridges, so that the side of each neurapophysis appears as 
if marked with the letter N in high relief. In the cervical and anterior dor- 
sal vertebrae there are, instead of a single inferior spinous process, two ridges 
which terminate each, in front, by a tubercle, as in the vertebra dentata of 
the Crocodile. 

Streptospondylus Cuvieri, nob. — The first fossil here to be noticed, which 
combines any of the above defined characters, is the anterior half of an an- 
terior dorsal vertebra, in the collection of Mr. Kingdon of Chipping Norton : 
it was found in the oolite in the vicinity of that town. 

The articular surfaces for the ribs are, as usual, close to the anterior part 
of the body of the vertebra, and this terminates by a convex articular surface, 
instead of being, as in the Crocodiles, concave : the second character is the 
remarkably deep pit behind each of the costal articular surfaces. It is as if a 
man had pressed his two thumbs forwards and inwards up to the first joint, 
into the substance of the body of the vertebra, until their extremities had 
nearly met. The aperture of each pit measui'es 1 inch by 10 lines. Sufficient 
of the neurapophysial arch is preserved to show the depression which has 
separated the two anterior ridges of its external surface ; but these charac- 
teristic ridges, with the transverse, spinous and oblique processes, are broken 
away. The medullary canal is compressed, and gives an oval vertical section, 
1 inch 6 lines high, and 1 inch 2 lines wide. Both upper and lower surfaces 
of the medullary canal are flat, and join the lateral surfaces at nearly a right 
angle. There is a slight ridge along each side of the medullary canal, indi- 
cating the neurapophysial suture, which extends here outwards and obliquely 

* Ann. du Mus. xii. p. 83, pi. x. xi. 

t The Saurian remains to which Prof. Bronn (' Lethsea Geognostica,' 1837, 8vo) has at- 
tached the name of Leptocranius, cannot belong, as he supposes, to the present genus, if it 
be true that the vertebrae are slightly constricted in the middle, and have both articular 
extremities concave, as in the following description : — "Die dazu gehorenden Wirbel-Korper 
in der jnitte wenig verengt, vorn und liinten sind concave Gelenk-flacUe." — p. 517. 



ON BRITISH FOSSIL REPTILES. 89 

downwards to above the middle of the costal depression. This depression is 
vertically ovate, with a deeper oblique pit in the middle, 2 inches in the long 
diameter, by 1 inch 6 lines across the broadest part. The texture of this 
vertebra is coarsely cellular, except for about two lines at the margin, where 
it is in very compact laminae. The anterior articular surface of the centrum 
is slightly and irregularly convex, being nearly flat at the upper part. 

There is a slight deviation from the symmetrical figure in the whole of 
this vertebral fragment. The body of the vertebra is much contracted in 
the middle, and suddenly expands to form the terminal articular surface. 
This character is likewise indicated by Cuvier in his Crocodile d' Honjleur* ; 
thus the transverse diameter of the middle of the vertebral body, across which 
the present fossil has been fractured, measures 2 inches 3 lines, Avhilst the 
same diameter of the convex articular extremity is 4 inches. 

The corresponding diameters of one of the anterior dorsal vertebrae of the 
Streptospondylus, described by Cuvier, are respectively 1 inch 7 lines, and 
2 inches 6 lines; whence we may conjecture that the length of the entire 
vertebra here described would have been 4 inches and a half. The ver- 
tical diameter of the articular surface is 3 inches 9 lines. 

The non-articular surface of the vertebral body is smooth, except near the 
articular extremity, where it is rather coarsely rugous. The inferior ridges 
and tubercles have disappeared at the part of the vertebral column to which 
the present vertebra has belonged. 

The osseous substance of the present fossil, like that of the bones of the 
Streptospondylus from Honfleur, presents a deep chocolate brown hue, and 
takes a bright polish. It is not completely mineralized ; the small cavities of 
a great part of the diploe are empty, and not filled with seraitransparent cal- 
careous spar, as in the Honfleur specimens. 

With the portion of the vertebra above described there was associated the 
extremity of a spinous process, which gradually expands to a rough obtuse 
quadrilateral summit. This spine is characterized by having a very rugged 
and thick ridge, developed from the anterior and posterior surface of what may 
be regarded as the ordinary spinous process, the sides of which are smooth, 
except near the summit. Inches. Lines. 

The length of this fragment of spine is ^ . . . 3 8 

The transverse diameter of the base 9 

The transverse diameter of the summit of the apex 1 6 

Antero-posterior diameter of spine 1 3 

Ditto, including the ridges 1 10 

In the Crocodile a thin plate is continued from the anterior and posterior 
edges of the thicker spinous processes ; but the Streptospondylus, if I am 
correct in attributing this spinous process to that genus, presents an extreme 
and peculiar development of this structure. 

A portion of a compressed, conical, hollow tooth, with a brown dense glis- 
tening dentine, covered by smooth enamel, and resembling that of the Mega- 
losaurits, was associated with the preceding vertebra. The length of this 
fragment of tooth is 2 inches 4 lines, but both ends are wanting. The breadth 
is 8 lines; the thickness 5 linesf . If it really belong to the Streptospondy- 
lus, it confirms the view of the aflRnity of that genus to Megalosaurus, which 
has been suggested by the characters of the vertebra. With the above frac- 
tured vertebra and tooth there were likewise found, in the oolite at Chipping 

* " Le corj)s de cette vertcbre, ainsi que des siiivantes, est beaucoup plus rttrcci dans son 
milieu que dans les Crocodiles connus." — Osseni. Foss. ed. 1824, torn. v. pt. 2. p. 156. 

t The teeth conjectured by Cuvier to belong to the Honfleur Streptospondylun are conical 
and striated. 



90 REPORT — 1841. 

Norton, a portion of a broad flat bone, with a convex, rough, articular labrum, 
nearly two inches thick, and of a fine cancellous structure, and fragments of 
long bones, with large medullary cavities and compact outer walls, of which 
the thickness equals about one-third of the diameter of the medullary canal. 

A more perfect specimen, referable to the present genus, is a posterior 
dorsal vertebra from the jet-rock (lias shale) near Whitby, and forms part 
of the collection of fossils of Mr. Ripley, surgeon of that town. 

It is much more complete than the preceding specimen, wanting only the 
spinous and transverse processes ; there is a slightly raised oval surface for 
the articulation of the head of the rib, on each side of the body, at its upper 
and anterior part, in the corresponding situation with that for the head of 
the rib on the four anterior dorsal vertebrae in the existing Crocodiles : this 
surface in the Whitby vertebra is relatively smaller and lower down than in 
the larger specimen of Streptospondylus from the oolite. 

The present specimen nearly corresponds in size with the dorsal vertebrae 
of the Honfleur Streptospondylus described by Cuvier*, as will be seen by 
the following admeasurements : — 



Whitby. 


Honfleur. 


Inches. Lines. 


Inches. Lines 


. 3 5 


3 8 


. 3 


3 3 


. I 3 


1 6 



Length, or antero-posterior diameter of body 
Transverse diameter of articular surface . . 
Transverse diameter of middle of body . . 

The principal character of the vertebrae of Streptospondylus, viz. the an- 
terior ball and posterior cup, is unequivocally demonstrated in this specimen 
by the presence of the oblique processes, which determine the anterior and 
posterior extremities of the vertebra ; the two articular surfaces which look 
upwards and inwards correspond with the convex extremity of the body of 
the vertebra ; while those on the oblique processes, which look downwards 
and outwards, overhang the extremity of the body of the vertebra, which 
is excavated by a moderately deep and regular concavity. 

To judge from the figures of two of the vertebrae of the Streptospondylusf 
from Honfleur, the characteristic fossa on each side of the body becomes 
shallower, and situated nearer the middle of the side of the body as the ver- 
tebrae approach the tail ; but the lateral fossae present both these modifications 
in the Whitby vertebra, which, from the articular surface of the rib, would 
seem to have come from the anterior part of the dorsal region of the spine. 

This vertebra presents the minor generic characters of the Streptospon- 
dylus in the length of the body, its lateral compression and inferior conca- 
vity, the two extremities being expanded to form the articular surfaces. 
The non-articular surface is smooth, except near the margins of the articular 
extremities. The line of the haemapophysial suture extends horizontally the 
whole length of the centrum. The two characteristic lateral buttress-like 
ridges rise from the two extremities of the base of the neurapophysis, and 
converge to the under part of the base of the transverse process, where they 
meet ; the depressions between and on each side of these ridges are deep : 
the third ridge extending from the anterior part of the base of the neura- 
pophysis to the anterior oblique process stands out in nearly as bold relief 
as those which support the transverse process. 

The articular surfaces on the oblique processes are bounded by a regular 
convex free margin ; their long diameter is 1 inch 10 lines, their short dia- 
meter 9 lines ; they are nearly flat : the anterior ones look inwards and up- 
wards ; the posterior downwards and outwards. 

* Loc. cit., p. 308. t Ossem. Foss. v. pi. ix. fig. 3 and 10. 



ON BRITISH FOSSIL. REPTILES. 91 

The two superior ridges, extending from the upper part of the anterior 
and posterior oblique processes to the transverse process of the same side, 
describe a regular concave curve. 

The vertical diameter of the fractured transverse process is 1 inch 3 lines, 
its transverse diameter is 1 inch. 

The great development of the superior part of the neural arch, and the 
strength and high relief of the buttress-like ridges supporting and strengthen- 
ing the different processes, indicate that the spinous process was unusually- 
large and massive. This process was not preserved in any of the vertebrae of 
the Honfleur Streptospondylus described by Cuvier, nor, unfortunately, in 
the present vertebra ; but its otherwise more perfect state adds another cha- 
racter to those by which the vertebrae of the Streptospondylus deviate from 
the Crocodilian type ; viz. a broad plate of bone extended transversely be- 
tween the two posterior oblique processes, and increasing in breadth as it 
ascends. The base from which the spinous process should rise, which is thus 
bounded by the oblique and transverse pi'ocesses, extends beyond, and, as it 
were, overhangs the whole body of the vertebra below ; and is hardly less re- 
markable for the height to which it is canned above the body. 

Thus from the highest part of the posterior oblique process to the lower 
margin of the corresponding articular surface of the vertebral centre mea- 
sures 6 inches ; the length of the vertebral centrum being 3 inches 5 lines : 
the contrary proportions prevail in the posterior dorsal and lumbar vertebrae 
of the existing Crocodiles. The breadth of the neural arch, where the la- 
teral buttresses terminate at the base of the transverse processes, is 6 inches. 

Streptospondylus major, nob. — The third British formation in which I have 
determined the remains of the genus Streptospondylus is the Wealden ; the 
specimens having been obtained from three localities, viz. Tilgate Forest in 
Sussex, and Brook Point and Culver Cliff in the Isle of Wight. The speci- 
mens differ in size from those already described, being larger than the Strep- 
tospondylus Cuvieri from the oolite ; I strongly suspect that they indicate a 
distinct species, but the means of comparison for the satisfactory establish- 
ment of the distinctions are as yet wanting. M. H. von Meyer has added 
nothing but the generic name to the observations of Cuvier, on which the 
claims of the present extinct Crocodilian to generic distinction are founded : 
these observations were taken from the dorsal vertebrae, atlas and axis, whilst 
the most characteristic of the Wealden vertebrae appertain to the middle part 
of the cervical region, from whence vertebrae of the reversed ball and socket 
system have not been hitherto recognized. 

These vertebrae I apprehend to be those on which Dr. Mantell has founded 
his description of the " Fourth system " from the Wealden. He says, " The 
vertebrae of the fourth system (tig. 4) are very rare, only six or seven have 
come under my observation. They are of the true Lacertian type, having the 
articular facets of the body convex posteriorly and concave anteriorly, and 
are loider than high, as in the Iguana and Monitors, and not in the reverse 
proportions, as in the recent Crocodiles. In two large but mutilated cervi- 
cals, the admeasurements are as follow : — 

Inch. 
" Height of the concave extremity 85 



Width of the same 4^ 



« ' 



Length of the body 6 

■ It is not obvious whether the annular part be divided by suture or other- 
wise ; the articular apophyses are horizontal and very strong ; the spinous 
process is destroyed *." 

* MauteU's Geology of the South-east of England, 8vo, 1833, p. 300. 



92 REPORT — 1841. 

It is the fortunate preservation of the two articular, or oblique processes, 
at one of the extremities of the annular part of this fine cervical vertebra, 
now in the Mantellian Collection, British Museum (No. ^j|), that has enabled 
me to correct the error into which the Founder of that noble collection has, 
in this instance, fallen : the flat oblong articular surface of each of these 
strong and -well-marked oblique processes looks downwards and outwards, 
determining them to be the posterior pair ; and they overhang the concave 
extremity of the body of the vertebra, determining that to be the posterior 
extremity. The opposite, or anterior end of the body of the same fossil, is 
convex. The few other large convexo-concave vertebrae from the Wealden 
of Tilgate correspond with the one here described in these important charac- 
ters of the genus Streptospondylus, and equally differ from the vertebrae of 
the Iguana, Monitors, and all other existing Sauria. Of the fossil cervical 
vertebra, 6 inches long, the anterior extrenuty of the body is further indicated 
by the position of the costal tubercle, or transverse process, which is deve- 
loped as a strong obtuse ridge from the middle part of that half of the cen- 
trum which is nearest the convex articulation. Beneath this ridge the sides 
of the body are concave, and converge to a broad ridge, which terminates 
the anterior part of the lower surface of the vertebra, and corresponds with 
the process given off from that part in the cervical vertebrae of the Crocodile. 
A second concavity, at the upper part of the side of the body, separates the 
transverse process, or ridge, from the base of the neural arch ; from which a 
second, or upper transverse process is developed for the attachment of the 
tubercle of the rib. 

The neural arch has been crushed down upon the centrum, and its anterior 
oblique processes and spine are broken away ; the upper, non- articular part 
of the strong diverging posterior oblique processes is convex. 

In the museum of Mr. SauU, F.G.S., Aldersgate Street, there is a cervical 
vertebra of the great Streptospondylus associated, as in the Mantellian Col- 
lection, with vertebrae of the Iguanodon and Cetiosaurus, all of Avhich have 
been washed out of the submarine Wealdan beds at the south side of the 
Isle of Wight, and thrown on shore near Culver Cliffs and Brook Point. 

The lower half of the sides of the centrum of the vertebra of the Strep- 
tospondylus are, like the preceding vertebra from Tilgate, concave and ob- 
liquely compressed, so as to converge to the anterior part of the under sur- 
face, which thus presents a triangular form, with the apex forming the obtuse 
anterior ridge, and the base turned backward and somewhat flattened. Each 
lateral concavity is bounded above by a short but broad transverse process, 
developed from the anterior half of that part of the centrum, and terminated 
by an oblong flattened surface for the articulation of the head of the cervi- 
cal rib ; which surface is about twice as long in the antero-posterior as the 
vertical direction. Above this process the centrum is again concave. The 
base of the neurapophysis is anchylosed to nearly the whole antero-posterior 
extent of the centrum, the course of the original straight suture being readily 
discernible. An upper transverse process is developed from the side of the 
base of the neurapophysis, affording a broader surface for the tubercle of the 
cervical rib than does the lower transverse process. Above the upper trans- 
verse process the neurapophyses converge obliquely to the base of the spinous 
process. The line of tlae base of the spine inclines forwards, and the thick- 
ness of the spine diminishes in the same direction. The difference in the 
height of the neural arch, and in the configuration of its external surface, 
which both the cervical vertebrae of the great Wealden Streptospondylus pre- 
sent, when compared with the dorsal vertebrae of the smaller specimens from 
the older oolite formations, is very great ; and the more remarkable, as in the 



ON BRITISH FOSSIL REPTILES. 93 

existing Crocodiles the height of the neurapophyses is greater in the cervical 
than in the dorsal region : as, however, the transverse processes in the Cro- 
codiles come off from a higher part of the neural arch in the dorsal than in 
the cervical vertebrae, the spine of the great Wealden Streptospondylus may 
possibly present modifications in the dorsal region corresponding with those 
remarkable ones which have been already described in the Whitby vertebra. 
The posterior articular processes in the cervical vertebra from Culver Point, 
are similar in all respects to those in the Tilgate specimen, and equally de- 
termine the fore and hind extremities of the vertebra. 

The following are admeasurements of the bodies of the two vertebrae of 
the Wealden Streptospondyhcs : — Tilgate. Culver Cliff. 

Inch. Lines. Inch. Lines. 

Transverse diameter of posterior concave 

articular surface 5 6 

Vertical diameter of posterior concave ar- 
ticular surface 3 6 4 6 

Antero-posterior diameter 6 5* 

Transverse diameter of the body across 

the inferior transverse processes ... 6 66 

Height from lower surface of centrum 

to the hind part of base of spine . . 7 9 
Antero-posterior extent of lower trans- 
verse process 2 2 2 4< 

Interspace between upper and lower trans- 
verse processes 2 

In the museum of the Geological Society of London there is a collection 
of rolled vertebra? from the coast at Brook Point, Isle of Wight, whicli, among 
the bones of Iguanodon and other gigantic Wealden genera, contains the 
centrum or body of a dorsal vertebra of the great Streptospondylus. This 
specimen, though much rolled and worn, is interesting, inasmuch as it ex- 
hibits the characteristic contraction of the middle and expansion of the ends 
of the centrum, together with unequivocal evidences of the marked depres- 
sion on each side, near the upper part of the anterior or convex end of the 
centrum. What remains of the depression is about the size of the end of a 
man's thumb. The convexity of the anterior extremity resembles in degree, 
and likewise in irregularity, that in the fractured vertebra of the Streptospon- 
dylus from the oolite, in Mr. Kingdon's collection. 

The present centrum is less depressed than those of the cervical region, 
but agrees with them in length, as the following dimensions show : — ■ 

Inches. Lines. 

Antero-posterior diameter 5\ 

Vertical diameter of concave end .... 5 6 

Transverse diameter of concave end ... 5 3 

Transverse diameter of middle of centrum . 3 

The vertebra from the forest marble alluded to in the note at p. 297 of 

Dr. Mantell's ' Geology of the South-east of England,' is a centrum from the 

posterior part of the dorsal region of the Streptospondylus major. 

The determination of the true nature of the convexo-concave vertebrae of 
the Wealden, and of the affinities of the reptile to which tliey belonged, be- 
sides extending our knowledge of the gigantic oviparous animals of that 

* It is evident that an inch at least, perhaps more, has been chiseled away from the ball 
wliich terminated the anterior end of the body of the specimen in Mr. SauU's collection. 

t The margins of the extremities being worn and rounded prevent the actual length being 
given. 



94 REPORT— 1841. 

epoch, removes one of the chief difficulties attending the determination of 
the true vertebral cliaracters of the Iguanodon. For if gigantic vertebrae, 
agreeing in the important character of their articular surfaces with the ex- 
isting Iguana, had actually been discovered, though of rare occurrence, asso- 
ciated with teeth of corresponding dimensions, but similar in form to those 
of the Iguana, there would have been strong ground for suspicion, that such 
vertebrae and teeth might be parts of the same species * 

The elimination of these, otherwise perplexing, ball and socket-jointed 
vertebra?, and their identification with the peculiar Crocodilian genus of Hon- 
fleur, on which M. H. von Meyer has imposed the name of Streptospondylus, 
forms, therefore, an essential step in the appropriation to the Iguanodon of 
its true vertebral characters. 

Cetiosaurus. 

Cetiosaurus brevis, nob. — The attempt to reduce to order the various forms 
and types of vertebrae, which the Wealden strata have yielded to test the saga- 
city of the interpreters of its organized treasures, was one of Dr. Mantell's 
earliest labours, and he states f that his first step was, with the able assist- 
ance of the Rev. W. D. Conybeare, to separate those that belonged to the 
Crocodile, Plesiosaurus and Megalosaurus, or rather which resembled those 
from Stonesfield. Many enormous vertebrae then remained, from which those 
belonging to the Iguanodon were to be chosen ; from these residuary speci- 
mens the characteristic ones of the PoiMlopleuron and Streptospondylus have 
already been eliminated, and I next proceed to remove from them the verte- 
brae which characterize the genus Cetiosaurus. 

Of the existence of vertebrae of this genus in the Wealden strata, I first 
became acquainted by the examination of Mr. SauU's collection of sea-rolled 
fossils washed out of the submerged Wealden beds, and deposited on the 
shores of the Isle of Wight, at Sandover Bay. 

The vertebrae in question present the well-marked generic characters of 
those of the dorsal region in the Cetiosaurus. as the breadth of the centrum, 
its subcircular contour, its median contraction and unequal concavity of the 
articular extremities ; as, also, the short antero-posterior extent of the neura- 
pophysis, and their anchylosis to the anterior part of the upper surface of the 
centrum : but they differ from the vertebrae on which the characters of the 
present genus were first founded J by the shortness of their antero-posterior 
diameters as compared with their breadth and depth, whence I propose to de- 
signate the species by the name of Cetiosaurus brevis. 

The centrum of a dorsal vertebra of this species from Culver Cliff mea- 
sures. In. Lines. 

in antero-posterior diameter 3 6 

transverse diameter 6 4 

vertical diameter 6 

* This suspicion is expressed, but with due caution, by Dr. Mantell in his ' Geology of 
the South-east of England.' " The somewhat angular vertebrae, described as appearing to 
constitute a Second System, I should be disposed, from their number, and from their so 
commonly occurring in the localities where the teeth of the Iguanodon most abound, to refer 
to that animal ; it must, however, be mentioned, that the concavo-convex vertebrae which 
correspond so entirely with those of the Iguana and Monitor, would seem to offer a more 
probable approximation ; yet the extreme rarity of the latter renders it questionable, since 
there appears no reason why the vertebrae shoiild not have been preserved in as consider- 
able numbers as the teeth." — p. 306. The vertebrae of the Iguanodon discovered by Mr. Ben- 
stead in the greensand quarries near Maidstone, are so crushed or so imbedded, as to prevent 
a satisfactory determination of both articular extremities. 

t Illustrations of the Geology of Sussex, 4to, 1827, p. 76. Geology of the South-east of 
England, 8vo, 1833, p. 278. 

X See Proceedings of the Geological Society for June 1841. 



ON BRITISH FOSSIL REPTILES. 95 

One of the articular ends * is rather more concave than the other, which, from 
the wearing away of the margins, appears slightly and unevenly convex. The 
contracted middle part of the vertebra is concave lengthwise, and pretty regu- 
larly convex in the direction transverse to the axis of the vertebra : the free 
surface is finely striated, and perforated here and there by vascular foramina : 
there is no lateral depression. The neurapophyses were broken off; their 
bases, instead of having their long diameter corresponding with the axis of 
the vertebra, as in Iguanodon, present it in the direction transverse to that 
axis, as in Plesiosaurus : they do not quite meet at the middle of the upper 
or neural surface of the centrum, but are there divided by a narrow longitu- 
dinal tract forming the lower part of the spinal canal. 

The antero-posterior extent of the anchylosed base of the neural arch is 
2 inches 6 lines : the transverse diameter, 5 inches. 

Two caudal vertebrae of the same species, also from Culver Cliff, present 
the same length and unequal concavity of the articular extremities ; the an- 
terior one, here determinable by the anterior position of the narrower hsema- 
pophyses, being the deepest : the sides of the body are more compressed, and 
more convergent towards the under surface ; so that, as the expanded margins 
of the articular ends are worn away, the centrum presents rather a triangular 
than a subcircular contour. The disproportion of its antero-posterior with its 
transverse and vertical diameters, distinguishes it from the caudal vertebras 
of the Iguanodon. The neurapophysis rises from the anterior three-fourths 
of the centrum, and sends forwards a subprismatic anterior oblique process, 
but does not develope a posterior one : it then contracts, and inclines to the 
base of the spine, which is much shorter than in the Iguanodon. The spi- 
nous process inclines backwards from the vertical axis of the centrum at an 
angle of 45°. A short transverse process is developed from the junction of 
the neurapophysis with the centrum. The haemapophysial surfaces appear 
single on both the anterior and posterior parts of the lower surface ; they are 
nearly flat, and slope towards each other. 

In. Lin. 

Antero-posterior diameter 3 

Transverse diameter 5 

Vertical diameter 5 

Height of vertebra to summit of spinet . 12 9 
Antero-posterior diameter of spine ... 2 10 
Thickness at posterior part of base ... 1 

Height of spine, 1st caudal 5 

Height of spine, 2nd caudal X . , , . . 4 

The characters and dimensions of these rolled vertebrae of Cetiosaurus 
from the submarine beds of the Wealden formation, although somewhat ob- 
scured by the circumstances under which they are brought to light, are suf- 
ficiently satisfactory to establish their generic character, and to give an use- 
ful approximative idea of their size and proportions. The corresponding 
bones from the Wealden of Tilgate Forest supply, by their more perfect state 
of preservation, the deficiencies of the Isle of Wight specimens, and further 
establish the co-existence of the Cetiosaurus with the Iguanodon, Strepto- 
spondylus, Megalosaurus and other extraordinary reptiles of that period. 
The vertebrae of the Cetiosaurus hrevis in the Mantellian Collection are the 

* Subsequently determined by more perfect specimens to be the posterior surface. 

t This is rounded off, but seems not to have been broken. 

X The 1st and 2nd do not here refer to the place of these vertebrse in the tail ; but if the 
vertebne were contiguous in the entire animal, the tail must be much shorter than in the 
Jgvanodon. 



96 REPORT — 1841. 

most gigantic specimens of Saurian remains that enrich it. They include the 
bodies of two dorsal vertebrae and four entire caudal vertebrae, which, if not 
consecutive, seem to have come not from distant parts of the basal portion of 
the tail of the same individual ; there are also the bodies of several of the 
smaller posterior caudal vertebrae. 

No. ^ (" Gigantic vertebra of Igucmodon" MS. Catalogue of Mantellian 
Collection,) is a posterior dorsal vertebra of the Cetiosaurus hrevis, and ex- 
hibits in a striking manner the peculiar characters of this species, viz. the 
great depth and breadth, especially the latter dimension, as compared with 
the length or antero-posterior diameter of the centrum or body of the ver- 
tebra. 

The posterior articular facet is, in this region of the spine, more concave 
than the anterior surface, a structure which approximates to that peculiar one 
which characterizes the Streptospondylus *. The contour of the articular 
ends is a full transverse oval : the middle of the centrum is strongly con- 
tracted, slightly concave in the longitudinal direction at the upper part of 
the side of the centrum, but deeply concave below, and with a slight indica- 
tion of a broad, obtuse longitudinal ridge along the middle of the concave 
under surface. In the Iguanodon the sides of the vertebral body are nearly 
flat in the vertical direction ; in the Cetiosaurus they are strongly convex. 
The surface at the middle of the vertebra is longitudinally striated with very 
fine, subparallel, short impressions : these grow deeper and more irregular at 
the thick, rugged and everted margins of the ai'ticular ends. 

The neurapophyses are firmly anchylosed here, as in the caudal region, 
and the line of the primitive suture is hardly discernible : their base is shorter 
than the short centrum, and is attached nearer its anterior part : in the Igua- 
nodon the neural arch is very nearly coextensive in antero-posterior diameter 
with the centrum supporting it : in a dorsal vertebra, of an Iguanodon 4^ 
inches in breadth, the antero-posterior extent of the base of the neural arch 
is 4- inches : in the present vertebra, which exceeds 7 inches in breadth, the 
antero-posterior extent of the base of the neural arch is 21 inches, and only 
2 inches a little above the base. The outer side of the neurapophysis is con- 
vex in the axis of the vertebra, and concave in the opposite direction as it 
ascends to the base of the transverse process, without exhibiting a trace of the 
ridges and hollows that so singularly characterize the same part in the dorsal 
vertebrae of the Streptospondylus Cuvieri. The antero-posterior diameter of 
the base of the transverse process is 2 inches ; its vertical diameter 1 inch. 
The diameter of the spinal canal is 1 inch 9 lines. The articular surfaces of 
the anterior oblique processes are flat, and look upwards and slightly inwards. 
In the Iguanodon their under margins, in the dorsal vertebrae, converge at 
nearly a right angle : in the present vertebra they incline to each other at an 
angle of 40°. The spinous process begins to rise immediately behind the 
anterior oblique processes by a narrow vertical plate, which seems as if it 

* Since the vertebrae of the Streptospondylus lose their peculiar convexo-concave charac- 
ter by the gradual subsidence of the anterior ball, as they approach the tail, the cervical 
vertebrae of the Cetiosaurus may approach, more nearly than do the dorsal ones, to the con- 
vexo-concave structure of the Streptospondylian vertebrje. The fact that, hitherto, only 
cervical vertebriE of the great Streptospondylus, and only dorsal and caudal vertebrae of the 
Cetiosaurus, have been discovered in the Wealden formations, has induced me well to con- 
sider the grounds for assigning them to Saurians of distinct genera. But the general con- 
stancy of the vertebraj of the same Saurian in their antero-posterior diameter, forbids the 
supposition of a vertebra of six inches in length in the neck being associated with one of 
three inches in length in the back. Additional evidence of a very decisive character must 
at least be obtained before the great Cetiosam- can be admitted to have resembled the Ptero- 
dactyle in such disproportionate length of the cervical vertebrae. 



ON BRITISH FOSSIL REPTILES. 97 

were nipped in between two shallow depressions ; its base ascends obliquely, 
and grows thicker to the posterior part of tlie neural arch. The summit is 
not entire. 

The height of this dorsal vertebra to the posterior origin of the spinous 
process is 9^ inches : from the base of the neurapophysis to the upper part 
of the transverse process, measures 3 inches. 

No. " 1^ " in the Mantellian Collection, (" Vertebra of Iguanodon, 8 inches 
in diameter," MS. Catalogue), may have actually presented that dimension 
when entire, for even now, not allowing for the margin of the posterior arti- 
cular surface which has been broken away, it measures 7 inches across that 
surface. This remarkable specimen, which may probably have afforded the 
type of the 'third or plano-concave' vertebral system, in the summary of the 
vertebral characters of the Wealden reptiles given by Dr. Mantell in his 
' Geology of the South-east of England*,' and which accords best with the 
characters assigned by M. H. von Meyer to the vertebrae of the Iguanodon\, 
presents, in fact, in a striking degree, those of the vertebrae of the Cetiosaurus, 
and belongs to a more posterior part of the dorsal region, perhaps to the loins, 
of the same individual, certainly to one of the same species, as the vertebra 
(No. 2133) last described. 

The anterior articular extremity makes the same approach to a plane sur- 
face, being slightlj^ concave below and very slightly convex above : the depth 
of the posterior concave surface at the centre is 9 lines. The general con- 
tour of the centrum has begun to change from the circular to the subqua- 
drate, which latter figure is more decidedly expressed in the anterior caudal 
vertebrae of the Cetiosaurus brevis. 

The upper half of the sides of the centrum are more concave in the axis 
of the vertebra than in No. 2133. The free surface presents the same de- 
gree of smoothness, and is pierced here and there by moderate-sized vascu- 
lar foramina. The spinal canal makes a slight depression in the upper part 
of the centrum : in the Iguanodon it is encompassed by the bases of the neu- 
rapophyses. The transverse diameter of the spinal canal is 1 inch, Avhich 
small dimension satisfactorily distinguishes the present enormous vertebra 
from those of the raammiferous class, viz. the Cetacea, to which in other re- 
spects it has the greatest similitude. The antero-posterior diameter of the 
base of the neurapophysis is 2 inches. 

The four anterior caudal vertebras in the Mantellian Collection, which are 
here assigned to the Cetiosaurus brevis, slightly increase in antero-posterior 
diameter, as is the case in the Cetiosaurus medius, as they recede from the 
trunk, which seems to indicate that the present gigantic marine Saurian must 
have had a capacious and bulky trunk, but propelled by a longer and more 
Crocodilian tail than in the modern whales. It is sufficiently evident, how- 
ever, that, even in the present short segment of the tail, with the slight in- 
crease of length, there is a diminution of height and breadth of the centrum, 
and a still more obvious subsidence of the neural arch, as the vertebrae recede 
from the trunk. As compared with the dorsal vertebrae, the chief change of 
form is the subquadrate contour produced by a lateral extension and flattening 
of the lower surface of the centrum, which is more essentially distinguished 
by four haemapophysial articular surfaces, two at the anterior and two at the 
posterior margins of this inferior surface. The articular surfaces at both ends 
of the centrum are now concave ; and the anterior one, which was nearly flat 
in the dorsals, is here the deepest ; it is one inch deep at the upper third of 

* 8vo, 1833, p. 296, fig. 3. t Palscologica, p. 212. 

184.1. H 



98 REPORT— 1841. 

the surface *. The sides of the centrum at the upper half are concave both 
lengthwise and vertically, forming a wide depression below the transverse 
process ; the middle part of the side begins to stand out and divide the upper 
from the lower lateral concavity, which character, being more strongly deve- 
loped in the hinder caudal vertebrae, gives the rhomboidal or hexagonal formf. 
The lower half of the side of the centrum is less concave than in the dorsal 
vertebrae. The broad inferior surface is also less concave antero-posteriorly 
than in the dorsal vertebrae, and is nearly flat transversely : it gradually con- 
tracts, in the transverse direction, in the posterior caudals, so as to take on the 
form of a longitudinal sulcus. The two anterior haemapophysial surfaces are 
separated from each other by an interval of two inches ; the two posterior 
surfaces, which are larger than the anterior ones, are similarly distinct. 

In the Iguanodon the haemapophysial surfaces are confluent on both the 
anterior and posterior parts of the under surface of the centrum, and the che- 
vron bones accordingly present modifications by which they may, when de- 
tached, be distinguished from those of the Cetiosaurus, 

The transverse processes have descended, as usual, from the summit to the 
base of the neural arch in the present anterior caudal vertebrae. They are 
short, compressed vertically, diminishing, and as if slightly twisted, so that the 
upper margin is turned forwards, at their extremity. The vertical diameter 
of the base of the transverse process in the largest of the present caudal ver- 
tebrae is three inches ; its anterior-posterior diameter one inch six lines ; its 
length two inches seven lines : the extremity terminates obtusely. The upper 
ridge-like termination of the transverse process is continued to the base of 
the anterior oblique processes. These processes are alone developed in the 
present vertebree, the posterior articular surfaces being impressed upon the 
sides of the posterior part of the base of the spine. The anterior oblique 
processes project almost horizontally forwards, diminishing, chiefly in vertical 
diameter, to an obtuse apex ; convex externally, flattened internally by the 
oblong articular surface, and separated by a fissure nearly one inch wide : 
the length of these processes, from the bottom of the intervening fissure in 
the second of the four caudals, where they are most entire, is two inches. 
When the vertebrae are placed in juxtaposition, these processes reach beyond 
the middle of the vertebrae next in front, and pinch, as it were, the back part 
of the base of the spine so as to impress upon it the surfaces representing the 
posterior articular processes. These processes are well developed, on the 
contrary, in the corresponding vertebraj of the Iguanodon, and overhang the 
posterior surface of the body of the vertebra to which they belong. The spi- 
nous process, which appears to be nearly perfect in the second caudal, is short, 
strong, and truncated at the summit. Its height from the anterior oblique 
processes is four inches : the total height of the vertebra is thirteen inches. 
The antero-posterior diameter of the side of the neural arch is two inches. 
The spinal canal is wider in these caudal than in the dorsal vertebrje, indica- 
ting the greater muscularity of the part deriving its nervous po-wer from the 
corresponding part of the spinal chord : its transverse diameter is one inch ten 
lines ; its vertical diameter is two inches. The neural arch is, as usual in the 
present genus, anchylosed to the anterior part of the upper surface of the cen- 
trum : one inch and a half of this surface is left free behind the attachment 

* The same modification of the articular extremities occurs in the caudal region of the ver- 
tebral column of the Plesiosaurus. See ' Report on Brit. Foss. Reptiles,' iiart i. Trans. Brit. 
Assoc. 1839, p. 58. 

t It is one of these posterior caudals of the Cetiosaurus, whicli is figured as the type of 
the " second vertebral system " in the ' Geology of the South-east of England/ p. 296, fig. 2. 



ON BRITISH FOSSIL REPTILES. 99 

of the arch. The finely wrinkled or fibrous character of the free surface is 
more strongly marked in these caudal than in the dorsal vertebrae. 

In the three succeeding vei'tebrae the neural arch diminishes in height, the 
anterior articular processes diminish in length, and the posterior articular im- 
pressions in depth. The upper and lower parts of the sides of the body be- 
come somewhat more concave; the posterior articular surface grows flatter. 

A detached chevron bone, eight inches in length, consisting of two haema- 
pophyses, anchylosed only at their distal or inferior extremities, and with their 
distinct proximal ends more divaricated than are the confluent ones in the 
Iguanodon, corresponds with the caudal vertebrae here described, and doubt- 
less belongs to the Cetiosaurus brevis. 

The following are dimensions taken from the four caudal vertebrae above 
described : — 



1st. 


2nd. 


3rd. 


4th. 


In. Lin. 


In. Lin. 


In. Lin. 


In. Lin, 


3 9 


4 2 


4 3 


4 3 


7 2 


7 1 


6 9 


6 4 


6 10 


6 8 


6 


6 



Antero-posterior diameter of centrum . 
Transverse diameter of centrum . . 
Vertical diameter of centrum . . . 

Of the present species of Cetiosaurus, I have examined specimens of the 
bodies of one dorsal and three posterior caudal vertebrae in the collection of 
Gilpin Gorst, Esq., which were obtained from the central strata of the Weal- 
den, near Battle Abbey, commonly called the ' Hastings beds.' 

The dorsal centrum closely agrees with those in the Mantellian Collection : 
its anterior surface is, as in them, nearly flat, or slightly convex ; the poste- 
rior surface is concave. 

In. Lines. 

The antero-posterior diameter 3 2 

The transverse diameter of the anterior surface ... 5 3 
The vertical diameter of the anterior surface .... .5 2 
A fracture of this centrum through its middle shows it to consist throughout 
of a coarse cellular texture. The neurapophyses, with an antero-posterior ex- 
tent of base of two inches three lines, are continuously anchylosed with the 
centrum, as in Mammalia, and leave about three quarters of an inch of the 
posterior part of the centrum free. The lower part of the spinal canal is 
horizontal ; its transverse diameter one inch three lines. 

The posterior caudal vertebrae present an antero-posterior diameter of nearly 
four inches, with a breadth of three and a half inches, and a depth of four 
inches, measuring to the lower part of the posterior haemapophysial surface. 
The antero-posterior length of the base of the neurapophysis is two inches 
two lines ; and it does not begin so close to the anterior part of the cen- 
trum as in the dorsal vertebra. The upper and lower portions of the side 
of the centrum are more distinctly separated by the comparative projection 
of the middle part, which gives the obscurely hexagonal form to these ver- 
tebrae. The inferior parts are most concave, and converge to form the sides 
of the longitudinal sulcus, to which the inferior surface of the centrum is re- 
duced at this part of the tail. It is plain, from these modifications of the ver- 
tebrae, that the tail must here have presented the compressed Crocodilian 
type ; and it is satisfactory to have these indications of the Saurian affinities 
of the present gigantic fossil, in consequence of the very close approximation 
of the larger vertebrae to the Cetaceous type. The vertical extent of the 
osseous basis of the tail was here augmented by strong haemapophyses, which 
have left more prominent articular facets on the under part of the centrum 
than in the larger anterior caudal vertebra; : these facets, instead of being in 
pairs, are confluent at the anterior, and at the posterior ends of the loAver sur- 

II 2 



In. Lin. 


In. Lin. 


In. Lin. 


In. 


Lin. 


4 3 


3 10 


3 7 


3 





3 10 


3 


2 8 


1 


4 


4 


3 3 


3 


1 


5 


4 6 


3 11 


3 10 


1 


2 



100 REPORT— 1841. 

face ; the posterior confluent pair, forming a triangular prominent surface, 
inclining obliquely forwards, and with its apex notched by the termination of 
the inferior sulcus. 

There are several posterior caudal vertebrae of the Cetiosauriis brevis in the 
Mantellian Collection,which closely correspond with those just described from 
the Hastings beds; four of these vertebrae give the following dimensions : — 

Nos. 2112. 2142. 2153. 

Antero-posterior diameter of centrum ^ . 
Transverse diameter of its articular end 
Vertical diameter of its articular end . . 
Vertical diameter at middle of the centrum 

The vertebrae figured in the ' Illustrations of the Geology of Sussex,' pi. ix. 
fig. 8, and pi. x. fig. 1 , are posterior caudal vertebrae of the Cetiosaurus brevis. 

Cetiosaurus brachyurus — A dorsal and a caudal vertebra from the Weal- 
den formation at Tetham, which agree in essential characters with the Cetio- 
saurus, and differ from those of Streptospondylvs, Megalosaurus, Iguanodon, 
Hylceosmirus, Poikilopleuron, and the Crocodilian vertebrae of the Wealden, 
offer at the same time proportions which forbid their reference to the Cetio- 
sauri brevis, medius and longus, and indicate a species distinguished by a 
shorter tail. 

The dorsal vertebra (No. ~, Mantellian Collection) presents a subcircular 
centrum, with the neui-apophyses anchylosed, but broken off; they are shorter 
than the centrum, and leave eight lines of its hind part uncovered. The 
anterior articular surface of the body is slightly convex at the upper, and con- 
cave at the under half : the posterior surface is uniformly concave : the body 
is constricted at the middle, but in a less degree than in the Cetiosaurus brevis, 
so that it is less deeply concave lengtliAvise : it is as convex transversely : a 
slightly-raised obtuse ridge separates two shallow sulci at the under surface 
of the vertebra. 

The caudal vertebra (No. ^) Mantellian Collection) presents a shallow 
and rather oblique sulcus along the lower surface. The hagmapophysial ar- 
ticulations are most marked at the posterior part of this surface. The sides 
of the centrum are less concave longitudinally than in the dorsal vertebra ; 
there is a vascular perforation on each : the articular ends of the body agree 
with those of the dorsal vertebrae. The following are dimensions of the pre- 
ceding vertebrae : — Dorsal. Caudal. 

In. Lin. In. Lin. 

Antero-posterior diameter of body ... 3 2 9 

Vertical diameter of articular end ... 4 3 3 10 

Transverse diameter of articular end . . 4 6 3 7 

These vertebrae closely corresponded in texture and character of the ex- 
ternal surface*. 

Cetiosaurus medius. — The remains of this Reptile have hitherto been dis- 
covered only in the oolitic strata below the Wealden. They appear to have 
been first noticed in a letter from John Kingdon, Esq., read at the meeting 
of the Geological Society held June 3rd, 1825, in which "he mentions the 
situation in which certain bones of a very large size, appearing to have be- 
longed to a Avhale and a crocodile, were lately found completely imbedded 
in the oolite quarries (lower oolite), about a mile from Chipping Norton, 
near Chapel House." It is principally on these bones, with others subse- 

* They are probably the bones alluded to in the Note at p. 221 of Dr. Mantell's ' Geology 
of the South-east of Enrfand.' 



ON BRITISH FOSSIL REPTILES. 101 

quently discovered and in the collection of Mr. Kingdon, that the characters 
of the Cetiosaurus were first determined*. They include a portion of the 
tail consisting of ten vertebrae ; the anterior and larger ones were five inches 
and a half in length, seven inches across the articular surface at each end of 
the body, and not less than two feet in vertical diameter, including the neural 
(superior) and haemal (inferior) spines. Both articular extremities are con- 
cave, the anterior one being rather the deepest; but the difference is less 
than in the Cetiosaurus brevis. The articular cavities become shallower in 
the posterior caudal vertebrae ; these gradually diminish in transverse and 
vertical diameter, but retain the same length, even %vhen they are reduced to 
two inches and one inch and a half in breadth. The body of the vertebra 
has no central cavity, in which respect the present, like the preceding species 
of Cetiosaurus, may be distinguished from the Poikilopleuro7i, where such 
cavity exists. The neurapophysis does not equal in antero-posterior extent 
the centrum or body of the vertebra, the disparity increasing in the posterior 
caudal vertebras : the arch is placed towards the anterior end of the vertebra. 
The hsemapophysial arch has a less contracted base than in the Igaanodon,, 
and the proximal extremities of the haemapophyses are free, as in the Cetio- 
saurus brevis. 

One of the ungual phalanges, which is conical, snbcompressed, and slightly 
curved, is traversed on each side by the usual vascular groove, curved with 
the convexity upwards, measuring five inches in length, and three and a half 
across its articular base. The bone alluded to in Buckland's ' Bridgewater 
Treatise,' vol. i. p. 115, and figured in Mr. Lyell's ' Elements of Geology' 
(1838), p. 384-, is a metatarsal of the Cetiosaurus. This fossil was found in 
the great oolite of Enstone, near Woodstock. 

A few large caudal vertebrae, and other bones of the Cetiosaurus, have been 
discovered in the oolite of the neighbourhood of the town of Buckingham, 
and form part of Dr. Buckland's museum. 

Some vertebrae, an entosternal bone, a coracoid, scapula, and fragments of 
long bones, belonging apparently to the same skeleton, were disinterred from 
the middle oolite during the railway cuttings near Blisworth, and are pre- 
served in the collection of Miss Baker at Northampton. The anterior trans- 
verse branch of the entosternum measures upwards of four feet across. The 
posterior caudal vertebree, which, like those from Chipping Norton, measure 
five inches and a half in length, have a more hexagonal form, resembling, 
in this respect, the terminal caudal vertebrae of the Cetiosaurus brevis of the 
Wealden ; they are, however, like the Chipping Norton specimens, of greater 
length. 

In the museum of Professor Sedgwick, there is a caudal vertebra of the 
Cetiosaurus from the neighbourhood of Stratford-on-Avon. The size of the 
fossils hitherto obtained of the Cetiosaurus medius, especially the vertebrae, 
if calculated according to the numbers and proportions of those of the Cro- 
codiles, gives a length of forty feet to this species. 

Cetiosaurus longus. — In Professor Buckland's museum are preserved some 
fossil remains, principally vertebrte, of another enormous Saurian, which 
the form and texture of the vertebrae prove to belong to the genus Cetio- 
saurus, but which differ in the proportions of the vertebras. One of these 
— a caudal vertebra — from the Portland stone at Garsington, near Oxford, 
measures in antero-posterior diameter of the centrum seven inches ; in trans- 
verse diameter, seven inches nine lines ; in vertical diameter of the centrum, 
six inches. Both articular extremities of the vertebra are slightly concave ; 
the body is slightly compressed laterally ; its middle part gives a subquadrate 
* See ProceecUugs of tlie Geological Society, June ISll. 



102 • BBPORT--1841. 

vertical section, with the angles slightly rounded ; the expanded articular ends 
are subcircular. A fractured dorsal or lumbar vertebra, from the same locality, 
■with transverse processes extending obliquely backwards from the upper part 
of the sides of the body, measures one foot across the nearly flat articular sur- 
face. The body of a caudal vertebra of the same species, from the Portland 
stone at Thame, measures seven inches four lines in antero-posterior diameter ; 
six inches six lines in transverse diameter ; and seven inches eight lines in ver- 
tical diameter. The under surface is concave lengthwise, and nearly flat from 
side to side ; it is perforated by many large vascular canals. A third caudal 
vertebra is somewhat shorter in antero-posterior diameter, but exceeds the pre- 
ceding in vertical diameter, which is eight inches. In all these vertebrae the 
neurapophyses are anchylosed to the centrum, and have a smaller antero-pos- 
terior extent at their base than the centrum, as in the preceding species of 
Cetiosaurus. In all the species the haemapophyses are articulated to the in- 
terspaces of two vertebree. To the Cetiosaurus longus is referable a vertebra, 
eight inches in length of body, and nine inches in transverse diameter, from 
the Yorkshire oolite at White Nab, which, together with some metatarsal bones, 
are deposited in the museum at Scarborough. No teeth, or fragments of jaws 
or cranium, have hitherto been discovered, which can, with certainty, be re- 
ferred to any of the preceding species. 

The names which I propose to give to these species refer to the relative 
length of their vertebrae, and from what we know of the constancy and re- 
gularity of this dimension in the back bone of individuals of the same species 
of Saurian, these specific names would, if we had the entire animals, be found 
to be as appropriate in reference to the relative length of their whole bodies. 

At present the Cetiosaurus brevis is known to me only by specimens from 
the Wealden strata ; the Cetiosaurus medius by fossils from the lower oolite, 
and the Cetiosaurus longus by a few vertebrae from both the upper and the 
lower oolite ; but how far these species should actually characterize these 
divisions of the great oolitic system, will depend on the results of ulterior 
researches and a longer experience. It is certain, however, that we have in 
these remains ample proof of the existence, at that period of the earth's his- 
tory which has been aptly termed the 'Age of Reptiles,' of another gigantic 
genus in addition to the Pliosaurus, Poikilopleuron, Streptospoiidylus, Igua- 
nodon, Megalosaurus and Hylceosaurus. 

The enormous Cetiosauri, some of which must have rivalled the modern 
whales in bulk, may be presumed to have been of strictly aquatic and most 
probably of marine habits, on the evidence of the sub-biconcave structure of 
the vertebrae, and of the coarse cancellous tissue of the long bones, which 
show no trace of medullary cavity. In the great expanse of the coracoid and 
pubic bones, as compared with the Teleosaurs and Crocodiles, the gigantic 
Saurians in question manifested their closer affinity to the Enaliosauria : 
their essential adherence to the Crocodilian type is marked by the form of the 
long bones of the extremities, especially the metatarsals ; and, above all, by 
the toes being terminated by strong claws. The main organ of swimming is 
shown, by the strength and texture, and vertical compression of the poste- 
rior caudal vertebras, to have been a broad vertical tail : and the webbed feet, 
probably, were used only partially in regulating the course of the swimmer, 
as in the puny Amblyrhynchus of the Gallipagos Islands, the sole known ex- 
ample of a Saurian of marine habits at the present period. 

DINOSAURIANS. 

This group, which includes at least three well-established genera of Sau- 
rians, is characterized by a large sacrum composed of five anchylosed ver- 



ON BRITISH FOSSIL REPTILES. 103 

tebrse of unusual construction, by the height and breadth and outward sculp- 
turing of the neural arch of the dorsal vertebrae, by the twofold articulation 
of the ribs to the vertebrae, viz. at the anterior part of the spine by a head 
and tubercle, and along the rest of the trunk by a tubercle attached to the 
transverse process only ; by broad and sometimes complicated coracoids and 
long and slender clavicles, whereby Crocodilian characters of the vertebral 
column are combined with a Lacertian type of the pectoral arch ; the dental 
organs also exhibit the same transitional or annectent characters in a greater 
or less degree. The bones of the extremities are of large proportional size, 
for Saurians ; they are provided with large medullary cavities, and with well 
developed and unusual processes, and are terminated by metacarpal, metatarsal 
and phalangeal bones, which, with the exception of the ungual phalanges, 
more or less resemble those of the heavy pachydermal Mammals, and attest, 
with the hollow long -bones, the terrestrial habits of the species. 

The combination of such characters, some, as the sacral ones, altogether 
peculiar among Reptiles, others borrowed, as it were, from groups now distinct 
from each other, and all manifested by creatures far surpassing in size the 
largest of existing reptiles, will, it is presumed, be deemed sufficient ground 
for establishing a distinct tribe or sub-order of Saurian Reptiles, for which I 
would propose the name o{ Dinosauria*. 

Of this tribe the principal and best established genera are the Megalosau- 
rus, the Hi/lcBosmirus, and the Iguanodon ; the gigantic Crocodile-lizards of 
the dry land, the peculiarities of the osteological structure of which distin- 
guish them as clearly from the modern terrestrial and amphibious Sauria, as 
the opposite modifications for an aquatic life characterize the extinct Ena- 
liosauria, or Marine Lizards. 

Megalosaurus. 

Of the gigantic Lacertians in question, the most remarkable are the Mega- 
losaurus, Iguanodon, and HylcBosaurus, the worthy fruits of the laborious re- 
searches of Prof. Buckland and Dr. Mantell. With respect to the Megalo- 
saurus, the great carnivorous terrestrial Lizard of the Wealden and Oolitic 
period, the lucid descriptions of its discoverer in his original Memoir and the 
'Bridgewater Treatise,' and the judicious remarks of Cuvier on its natural 
affinities, leave little to be added, save the observations on the sacrum, to the 
present brief record of the strata and localities in which the remains of the 
Megalosaurus have been found. 

The most complete collection of the bones of this genus has been derived 
from the oolite of Stonesfield, where the original specimens were first dis- 
covered. Dr. Buckland now possesses in his valuable collection portions of a 
lower jaw, the principal fragment containing a tooth fully developed, and the 
germs of several others ; detached dorsal, caudal, and a series of five sacral 
vertebrae, ribs, two coracoid bones, a clavicle, humerus, radius, an ilium, an 
ischium, a femur, fibula, metacarpal and metatarsal bones. 

These parts have not been discovered so associated together as to prove 
them to belong to the same animal ; but the peculiar characters of some of 
the bones, which distinguish them from the other oviparous reptiles of the 
same strata, and the agreement in texture and proportionate size of the others, 
render their reference to the Megalosaurus highly probable. 

* Gr. (Jeivos, fearfully great ; cravpos, a lizard. In the tabular arrangement of extinct 
Saurians founded by M. Herni. v. Meyer on the development of their organs of motion, the 
Megalosaurus and Iguanodon are grouped together in Section B, with the following cha- 
racter: — Saurians with locomotive extremities like those of the bulky tenestrial Mammals: 
•' (Saiiricr mit Ghedmasseu iihnlich denen der schweren Landsaiigethiere)." — Palseologica, 
p. 201. No other grounds arc assigned for their separation from other Sauriaus. 



104 REPORT — 1841. 

The essential characters of the most authentic of these remains prove the 
Megalosaurus to have been closely related to the Lacertian division of the 
Saurian order ; but the teeth, the vertebrae, and some of the bones of the ex- 
tremities, indicate its affinities to the Crocodilian group, and all these parts 
manifest more or less stronglj' the peculiar characters of its own remarkable 
family. In the instructive and characteristic portion of the lower jaw, the 
sockets, like the teeth, are compressed, and are separated by complete parti- 
tions ; but they are so much wider than the teeth, as to suggest the existence 
of a greater proportion of ligamentous gum at the upper part of the alveolar 
tract in the recent animal than in the Crocodiles. " The outer rim of the 
jaw rises almost an inch above the inner rim, and forms a continuous lateral 
parapet, supporting the teeth externally ; whilst the inner rim throws up a 
series of triangular plates of bone, forming a zigzag buttress along the in- 
terior of the alveoli. From the centre of each triangular plate, a bony septum 
crosses to the outer parapet, thus completing the alveolus*." There is a 
slight groove and ridge along the inner side of the sockets, and it is at this 
groove, at the interspace of each triangular plate, that the apices of the new 
teeth protrude. The teeth have compressed, conical, pointed crowns, with 
trenchant and serrate anterior and posterior edges. They appear straight 
when they first protrude, but are bent in the progress of growth ; in the course 
of development the crown of the tooth is solidified, and the anterior margin 
at the base of the crown becomes smooth and convex. The smooth enamelled 
surface of the tooth presents fine polished wrinkles. 

In all existing Lizards the teeth are anchylosed, either to the side of an 
outer alveolar parapet, according to the pleurodont type, or to its summit, ac- 
cording to the acrodont type. The double parapet, inclosing and concealing 
the germs and the bases of the full-grown teeth, is a remarkable approach in 
the present gigantic Dinosaur to the Crocodilian structure, the similarity in 
this respect no doubt resulting from a similar necessity in the carnivorous 
Megalosaur for a firm lodgment of the destructive maxillary weapons. The 
higher development of the outer alveolar parapet bespeaks the affinity of the 
Megalosauriis to the Lizards : in the form of the teeth it approaches nearest 
to the Varanian family, which at the present day includes the largest, and most 
carnivorous species of Lizard. 

VertebrcE. — The Megalosaur deviates more decidedly from the existing Mo- 
nitors and Lizards in its vertebral characters. These are afforded, at present, 
by the sacral, a few costal and caudal vertebrae. The articulating surfaces of 
the body of the vertebra are nearly flat or slightly concave, as in the ccelospon- 
dylianf Crocodiles. The non-articular surface is remarkably smooth and po- 
lished. The body is much contracted in the middle : the margins of the ex- 
panded articular extremities are thick and rounded off". The middle contracted 
part of the body is nearly cylindrical, being nipped in, as it were, by a more 
or less deep longitudinal fossa on each side, just below the base of the neural 
arch, but again slightly expands to support that part. The length of the base 
of the neurapophysis is nearly equal to that of the centrum : the suture is per- 
sistent, as in Crocodiles ; its course is undulating, and it rises in the middle. 
The neurapophysis ascends and inclines outwards, to form, at a height above 
the centrum equal to three-fourths its vertical diameter, the margin of a broad 
platform of bone, from the sides of which the transverse processes are deve- 
loped, and from the middle part the spinous process. A strong ridge or but- 
tress of bone extends from the posterior angle of the base of the neurapophy- 

* Transactions of the Geological Society, 2nd Series, vol. i. p. 395. 
t I find this collective term convenient in application to those Crocodilians which have 
the vertebrae concave at both ends. 



ON BRITISH FOSSIL REPTILES. 105 

sis obliquely forwards to the under part of the transverse process ; behind 
which ridge there is a deep depression, separating it from the posterior arti- 
cular process. These processes are relatively smaller than in the Iguanodon, 
and do not project beyond the hinder end of the centrum. The spinal plat- 
form descends in a gentle curve from the posterior to the anterior oblique 
processes : the base of the strong and thick spinous process follows this curve 
along the middle line of the platform ; its antero-posterior extent was 4^ 
inches, in a vertebra having the centrum of the same length, with a vertical 
diameter of 4 inches, and measuring 7^ inches from the under part of the 
centrum to the posterior part of the base of the spine. 

Sacrum. — The sacrum of the Megalosaurus consists of five anchylosed 
vertebrae, and it is remarkable enough, considering how small a proportion 
of the recognizable bones of this rare reptile has been found, that the present 
characteristic part of the vertebral column of three different individuals should 
have been obtained : one sacrum, from Stonesfield, is in the museum of Dr. 
Buckland at Oxford ; a second sacrum, from Dry Sandford, in the museum of 
the Geological Society ; and a third sacrum, from the Wealden formation, in 
the British Museum. 

I have studied each of these specimens with much attention, which a recog- 
nition of their remarkable structure has well repaid. 

It would seem that Cuvier did not regard the five anchylosed vertebrae 
figured in Dr. Buckland's original memoir, as the sacrum of the Megalosaurus. 
They are briefly alluded to in the second and fourth editions of the ' Osse- 
mens Fossiles,' and in the description of the Plate, in which Dr. Buckland's 
figure is reproduced as a ' Suite de cinq vertebres de Megalosaurus.' In truth 
the sacrum was not known to be represented, at that time, in any Saurian by 
more than two vertebrfe, and therefore Dr. Buckland mentions this part in 
his original memoir as " five anchylosed joints of the vertebral column, in- 
cluding the two sacral and two others, which are probably referable to the 
lumbar and caudal vertebrae*." In contemplating this series of five anchy- 
losed vertebrae, so new in Saurian anatomy, my attention was first arrested by 
the singular position of the foramina for the transmission of the nerves from 
the inclosed spinal marrow. These holes, which, in the plate illustrating Dr. 
Buckland's important memoir f are represented above the bodies of the three 
middle vertebrae, are natural, and accurately given : the smooth external sur- 
face of the side of the vertebra may be traced continuing uninterruptedly 
through these foramina, over the middle or nearly the middle of the centrum, 
into the surface of the spinal canal. 

But the normal position of these foramina throughout the vertebral co- 
lumn in all other reptiles is at the interspace of two vertebras, whence by 
French anatomists these holes are termed ' trous du conjugaison.' In the 
sacrum of the Oxford Megalosaur, however, it is evident that above the an- 
chylosed intervertebral space a thick and strong imperforate mass of bone 
ascends to the base of the spinous process, leaving it to be conjectured either 
that the nerve had perforated the middle of the neurapophysis, or that these 
vertebral elements had undergone in this region of the spine a change in their 
usual relative position to the centrum. Previous researches into the compo- 
sition and modifications of the vertebrae in the different classes of Vertebrata 
soon enabled me to recognize the peculiar condition and analogies of the five an- 
chylosed vertebrae of the Megalosaurus ; with a view to illustrate which I shall 
premise a few observations on the different relative positions which the peri- 
pheral vertebral elements may take in regard to the central part or body. 
The lateral vertebral elements, or ribs, the inferior laminae or haemapophyses, 
* Gcol. Trans., 2nd Series, vol. i. p. 395, pi. xlii. fig. I. t Ibid- 



106 REPORT — 1841. 

the superior laminae or neurapophyses, are all subject to such changes ; but 
the neurapophyses are much more constant in their place of attachment than 
the others. In Mammalia the ribs for the most part are joined to the inter- 
space of two centrums ; in Reptiles each pair is attached to a single centrum. 
In Fishes, and the Mosasaur among Reptiles, the hsemapophyses depend, each 
pair from its proper centrum ; in other Reptiles and Mammalia they are arti- 
culated to the interspace of two vertebrae, leaving a half-impression on each 
of the contiguous centrums. The neurapophyses present a degree of con- 
stancy in their relation to the body of the vertebra corresponding •with the 
importance of their function. In Mammalia I know of no exception to the 
rule, that each neural arch is supported by a single centrum : in Birds no ex- 
ception has hitherto been recorded ; but among Reptiles the Cheloniae* oiFer 
in those vertebrae, in which the expanded spinous processes contribute to form 
the carapace, the interesting modification analogous to those noticed in the 
lateral and inferior vertebral elements, viz. a shifting of the superior laminae 
from the middle of the body to the interspace of two adjoining centrums ; 
whereby that part of the spine subject to greatest pressure is more securely 
locked together, and a slight yielding or elastic property is superadded to the 
support of the neural arch. 

The same modification is introduced into the long sacrum of birds ; each 
neural arch is there supported by two contiguous vertebrae, the interspace 
of which is opposite the middle of the base of the arch above, and the ner- 
vous foramen is opposite the middle of each centrum. It is this structure, 
beautifully exemplified in the sacrum of the young Ostrich, which Creative 
Wisdom adopted to give due strength to the corresponding region of the 
spine of a gigantic Saurian species, whose mission in this planet had ended 
probably before that of the Ostrich had begun. 

The anchylosed bodies of the sacral vertebrae of the Megalosaur retain 
the distinguishing characters which have been recognized in the dorsal and 
caudal vertebrae, in regard to the smooth and polished surface of their middle 
constricted part ; the cylindrical, or nearly cylindrical transverse contour of 
this part below the lateral depression ; their expanded, thickened and rounded 
articular margins, and also, though in a somewhat less degree, their relative 
length as compared with their breadth and height. The three middle sacrals 
are, however, somewhat shorter than the two terminal ones. 

In. Lin. 

Antero-posterior diameter of centrum of fifth sacral ... 4 10 

Vertical diameter of centrum of fifth sacral 4? 1 

Transverse diameter of centrum of fifth sacral 4 6 

Vertical diameter of the middle of the body 2 6 

Total height of fourth sacral vertebra II 

The neural arches of the first three sacral vertebras rest directly over the 
irrterspaces of the subjacent bodies ; that of the fourth derives a greater pro- 
portion of its support from its proper centrum ; aud that of the fifth, which 
rests by its anterior extremity on a small proportion of the fourth centrum, 
is extended over nearly the whole length of its own centrum, so that in the 
caudal vertebrae the ordinary relations of the neural arch and centrum are again 
resumed. In the four first sacral vertebrae the base of the neural arch ex-' 
tends half way down the interspace of the bodies, and immediately developes 
from its outer part a strong and short transverse process (broken and rounded 
off in the fossil). From the base of this process the neurapophysis expands 

* Cuvier describes the exceptional structure above alluded to in these Reptiles, and like- 
wise cites the Chondropterygians ; ' Le9ons d'Anat. Comparee,' ed. 1836, torn. i. p. 213. 



ON BRITISH FOSSIL REPTILES. 107 

upward, forward and backward, is joined by vertical suture to similar ex- 
pansions of the contiguous neurapophysis, an-d terminates above in a ridge 
of bone, at right angles to the suture ; this ridge, with those of the other 
neurapophyses, extends longitudinally above the transverse processes the 
whole length of the sacrum, and forms the margin of the platform from which 
the spinous and accessory processes are developed. The platform is further 
supported by a compressed ridge of bone extended from the upper part of 
the transverse process, like a buttress, to the middle of the horizontal ridge. 
On each side of the buttress there is a depression, which is deepest in front. 
The spinous process is not developed, as in the dorsal vertebrae, immediately 
from the platform, but a shorter, vertical plate of bone, of nearly the same 
longitudinal extent as the true spine, is developed on each side of, and parallel 
with its base ; the height of these accessory spines in the third sacral vertebra 
is three and a half inches. The true spinous process begins to expand longi- 
tudinally, and when near tne summit of the accessory spines, is joined by ver- 
tical siiture with the similarly expanded neighbouring spines, so that the sa- 
crum is crowned by a strong continuous vertical longitudinal ridge of bone, at 
least along the four first vertebrae ; the broad spine of the fifth being rounded 
off anteriorly, and separated by a narrow interspace from that of the fourth. 
Besides this modification of the spine, and the more normal position of the 
neural arch of the fifth anchylosed vertebra, the origin of the transverse pro- 
cess has been suddenly raised to the level of the spinal platform, and it is sup- 
ported by two converging ridges of bone from the side of the neural arch be- 
low. The origin of the transverse processes of the first sacral is also placed 
higher than the three middle ones, in which the several peculiarities of struc- 
ture above described are most strongly marked. 

The specimens of sacrum of the Megalosmirus in the British Museum, 
and that of the Geological Society, present the same structure as that above 
described in the original specimen at Oxford. Part of the fifth sacral ver- 
tebra is wanting in the specimen from Dry Sandford. The rest are cha- 
racterised by the same smooth and polished surface, rich brown colour, con- 
traction of the middle of the body, its cylindrical form transversely, and the 
longitudinal fossa below the annular part. The length of this series is one 
foot six and a half inches ; the second and third sacral vertebrae are rather 
shorter than the rest. The first sacral vertebra, which was not anchylosed 
to the last lumbar, gives the following dimensions : — 

In. Lin. 

Antero-posterior diameter of centrum 5 

Vertical diameter of anterior articular end .... 4 
Transverse diameter of anterior articular end ... 4 6 
The neural arch seems not to have been co-extensive in length with the cen- 
trum, but rests on its anterior three-fourths. A strong and short transverse 
process extends obliquely upwards and backwards from each side of the arch ; 
the antero-posterior diameter of the base of this process is two inches, its ver- 
tical diameter one and a half incii. In the second sacral vertebra the neural 
arch ha.s moved forward upon the interspace between the first and second 
sacral bodies, and developes from a lower part of its base a stronger, thicker 
and longer transverse process, directed outwards and forwards. The third 
neural arch has its base transferred directly over the interspace of the second 
and third centrums ; the diameters of the base of its transverse processes are 
three inches and two and a half inches : they incline slightly backwards. The 
fourth neural arch descends lower down upon the interspace between the third 
and fourth centrums. The fifth neural arch, as in the Oxford specimen, ex- 
tends a little way across the interspace between the fourth and fifth centrums, 



108 REPORT— 1841. 

but nearly resumes its ordinary place. The second and third sacral vertebrae 
are not so regularly convex below in the transverse direction, but their sides 
converge so as to give a slight indication of a broad obtuse ridge. The dia- 
meter of the spinal canal in the first and last sacral vertebras is one inch. 

The five vertebrae are not anchylosed in a straight line, but describe a 
gentle curve, with the concavity downAvards ; the series of transverse pro- 
cesses or sacral ribs, forms a curved line in the opposite direction, in conse- 
quence of their different positions. The summits of the anchylosed spines 
being truncated, describe a curve almost parallel with that of the under part 
of the vertebrae. The contour of the hinder part of the body of the present 
gigantic carnivorous lizard, doubtless raised high above the ground upon the 
long and strong hind-legs, must have been diffei'ent from that of any existing 
Saurians. In these the relatively shorter hind-legs, being directed more or 
less obliquely outwards, do not raise the under surface of the abdomen from 
the ground ; it is the greater share in the suppoi't of the trunk assigned to 
the hind-legs in the Megalosaur which made it requisite that, as in land 
mammals, a greater proportion of the spine should be anchylosed to transfer 
the superincumbent weight thi'ough the medium of the iliac bones upon the 
femora. 

The femur, like the teeth and vertebrae, exhibits a mixture of the charac- 
ters of the Monitor and the Crocodile. It is arched in two directions, being 
at first concave in front, and then behind. Its articular head is directed for- 
wards, and has behind it a compressed and rather salient trochanter ; it 
thickens towards the distal end, and there terminates in two unequal con- 
dyles. Near its upper third it has an expansion on both the inner and the 
outer side, like the one which is seen on the internal side of the femur in the 
Crocodile. The femur of the Monitor is less arched. The medullary canal 
is wide, which removes the Megalosaur from the Crocodiles, and indicates, 
as Dr. Buckland has well shown, its aptitude for a more terrestrial life. 

The ribs, which from their colour, texture, and proximity of deposit, belong 
most probably to the Megalosaurus, present a double articulation with the ver- 
tebral column ; the head is supported on a long and strong compressed neck, 
thickest at its under part ; the tuberosity is large. One of the small cervical 
false ribs is preserved, the free extremity of which gradually tapers to a point. 

The scapula is a thin, slightly-bent plate, of equal breadth, except where it 
is expanded and thickened towards the humeral end, but thinning off again 
towards the articular margin. The chief support of the humerus seems to 
have been afforded by a large and broad coracoid. The antero-posterior 
diameter of one of these bones, taken across the median, thin, slightly con- 
vex margin, is two feet three inches. The thickened process for the articu- 
lation with the scapula has a deep and narrow notch in front, and the deep 
and wide glenoid cavity for the humerus behind it ; the posterior boundary 
of this cavity projects outwards in the form of an obtuse process. A short 
but strong process projects from the anterior part of the coracoid analogous 
to that which in the Varanian Monitors and most other Lizards abuts against 
the epicoracoids, and which bespeaks the existence of the epicoracoids in the 
Megalosaurus. The characteristic coracoid bone illustrates most unequivo- 
cally the affinities of the Megalosaurus to the Lacertian group of reptiles ; 
but compared with the coracoid of a Varanian Monitor, four feet nine inches 
in length, it is sixteen times as large. This magnitude in a reptile, Cuvier 
justly observes, is quite appalling ; for, other proportions being the same, the 
Megalosaurus must have exceeded seventy feet in length. 

A long and slender bone, nearly two feet in length, most resembles the 
clavicle of certain lizards, especially, as Cuvier remarks, those of the great 



ON BRITISH FOSSIL REPTILES. 109 

Sclncus. It is slightly arcuated longitudinally, subtrihedral in the middle, flat- 
tened and expanded at the two extremities. If it be really a clavicle, it forms 
as characteristic an indication of the Lacertian affinities of the Megalosaurus 
as the coracoid. According to the proportions of the clavicle in existing lizards, 
Cuvier observes that it bespeaks an animal nearly sixty feet in length. 

A subcompressed, three-sided bone, flattened and slightly expanded at one 
end, thickened and more suddenly extended transversely at the opposite end, 
which formed part of a large cotyloid cavity, is most likely an ischium ; its 
length is 18 inches; its breadth, at the middle of the shaft, 5 inches ; at its 
articular end 9 inches, the thickness of this end being 4 inches. The ascend- 
ing shaft of this bone is slightly twisted, convex and smooth on the outer side, 
flat and rough on the inner side. 

Other bones, not improbably belonging to the Megalosaurus, are preserved 
in the British and Oxford Museums, and in the private collections of Messrs. 
Holmes and Saull ; but further evidence of their Megalosaurian character 
must be obtained before a description of them can be profitably applied to the 
reconstruction of the skeleton of the present carnivorous Dinosaur, 

A few words, however, may be added, touching the size of the Megalosau- 
rus ; for it appears to me that the calculations which assign to it a length of 
60 and 70 feet are affected by the fallacy of concluding that the locomotive 
extremities bore the same proportion to, and share in the support of, the body, 
as they do in the small modern land lizards. 

The most probable approximation to a true notion of the actual length of 
the Megalosaurus, is that which may be obtained by taking the length of the 
vertebrge as the basis. The antero-posterior dimension is the most constant 
which the vertebrae present throughout the spine : in most Crocodilian and 
Lacertian reptiles the cervical vertebrae are a little shorter than tlie dorsal ; 
but these are of equal length, and the caudal vertebrae maintain the same 
length to very near the extremity of the tail. 

As the dorsal vertebree of the Megalosaurus agree, in the important cha- 
racter of the mode of articulation of the ribs, with the Crocodiles, it may be 
regarded as most probable that they also corresponded in their number. This 
does not exceed 14 in recent Crocodiles, nor 16 in any of the known extinct 
species ; taking, then, the latter number, and adding to it 7, the usual number 
of the cervical vertebrae in Crocodiles, we may allow the Megalosaurus 23 
vertebrte of the trunk. 

The length of the body of a large dorsal vertebra of the Megalosaurus in 
the British Museum is 41 inches : from the analogy of the Iguanodon, in 
which several dorsal vertebrae have been discovered in their natural juxta- 
position, it is probable that the thickness of the intervertebral substance did 
not exceed one-third of an inch : but if we multiply 23 by 5, not allowing 
for the probable shortness of the cervical vertebrte, we only then attain a 
length of 9 feet 7 inches. If, however, setting aside the analogy of the Me- 
galosaurus to the Crocodiles in the structure of the vertebrte, we take that 
species of Lacertian which it most resembles in the structure of the teeth, and 
found our calculation on the number of vertebrae of the trunk in such lizard, 
then, the great carnivorous Varanian Monitor of Java having 27 vertebrte 
of the trunk, we do not, even calculating the same number of vertebraj to 
have occupied each a space of five inches in the Megalosaurus, obtain a length 
of trunk exceeding 11 feet 3 inches. 

I should consider the first calculation, or about 10 feet, to have been the 
most probable natural length. 

To this we must add 1 foot 10 inches for the known length of the sacrum. 
Thus 12 feet will be a fair or even a liberal allowance of length from the 



110 REPORT — 1841. 

occiput to the beginning of the tail. In Crocodiles the skull equals about 12 
dorsal vertebrae in length. In the Java Monitor the proportion of the head is 
less. In the Iguana the cranium does not exceed 6 dorsal vertebrae in length. 
We may consider therefore 5 feet, taking the Crocodile as the term of 
comparison, as probabl)- not below the length of the head of the Megalosaur. 
With regard to the tail, this includes between 36 and 38 vertebras in Croco- 
dilians, but varies from 30 to 115 in the small existing Lacertians, in many 
of which it is a prehensile organ, aiding them in climbing and other actions 
suitable to their size. It is very improbable that the tail should have pre- 
sented such unusual proportions in the great Saurian under consideration, 
and indeed very few caudal vertebrae of the Megalosaur have been as yet 
discovered, and none exceeding 4 inches in length. Allowing the Megalo- 
saur to have had the same number of vertebrae as the Crocodile, and multi- 
plying this number 36 by 4-^, a length of 12 feet 6 inches is thus obtained for 
the tail. A calculation on this basis thus gives, in round numbers, 

Length of head B feet. 

Length of trunk, with sacrum 12 — 

Length of tail 13 — 

Total length of the Megalosaurus 30 — 

Upon this mode of obtaining an idea of the bulk of the present extinct rep- 
tile I am disposed to place the greatest reliance, and conceive that any error 
in it is more likely to be on the side of exaggeration than of curtailment. 
From the size and form of the ribs it is evident that the trunk was broader 
and deeper in proportion than in modern Saurians, and it was doubtless raised 
from the ground upon extremities proportionally larger and especially longer, 
so that the general aspect of the living Megalosaur must have proportionally 
resembled that of the large terrestrial quadrupeds of the Mammalian class 
which now tread the earth, and the place of which seems to have been supplied 
in the oolitic ages by the great reptiles of the extinct Dinosaurian order. 

Besides the Stonesfield slate, the remains of the Megalosaurus have been 
found in the Bath oolite immediately below that slate, and in the cornbrash 
above it. The other formation in which the remains of the Megalosaur 
occur, next in importance to the Stonesfield slate, is the Wealden strata. 
Dr. Mantell has discovered in the ferruginous clay of the Forest of Tilgate 
a fine vertebra, and a portion of the femur of the Megalosaurus, 22 inches 
in circumference. Many teeth have been discovered altogether of the same 
form as those found by Dr. Buckland. Some fragments of the metacarpus 
and metatarsus from this locality, were thicker than those of a large hippo- 
potamus. Mr. Holmes, surgeon at Horsham, possesses a good caudal ver- 
tebra, and some other parts of the Megalosaurus from the ferruginous sand 
near Cuckfield in Sussex. Remains of the Megalosaurus occur in the Pur- 
beck limestone at Swanage Bay. In some of the private collections in the 
town of Malton, Yorkshire, are teeth, unquestionably belonging to the same 
species as the Stonesfield Megalosaurus, ivoxaihQ oolite in the neighbourhood 
of that town. 

The tooth from the New Red Sandstone of Warwick figured in the Memoir 
by Messrs. Murchison and Strickland*, and referred to the Megalosaurus, be- 
longs to another genus of Lacertian, more nearly allied to the PalcBosaurus 
of the Bristol conglomerate. 

* Geol. Trans., 2nd Series, vol. v. pi. xxix. fig. 7. 



on british fossil reptiles. ill 

Hyi-^osaurus. 

A second well-marked genus of Dinosaurian Reptiles is founded upon a 
large portion of the skeleton of the reptile to which the name at the head of 
this section has been applied by its discoverer, Dr. Mantell. 

In assigning to this genus its present place in the Dinosaurian order, I 
have been guided by the structure of the vertebral column, especially the 
sacrum, and by the following considerations. The distinct alveoli in the jaws 
of the Megalosaurus, and the resemblance of its teeth to those of two ex- 
tinct Crocodilians, viz. the Argenton species and the Suchosaurus, seemed 
to claim for that great carnivorous Dinosaur the next place to the Crocodi- 
lian order, among which the Streptospondyliis, as has been shown, seemed to 
make the closest approximation to the Megalosaurus, in the great height, 
complexity and strength of the neural arch of the vertebrae. In the present 
genus, which there is good reason for believing to have resembled the Lizards 
more than the Crocodiles in its dental characters, an affinity to the Loricate 
Sauria is manifested not only by the structure of the vertebrae and ribs com- 
mon to it with other Dinosaurs, but likewise by the presence of dermal bones, 
or scutes, with which the external surface was studded. 

The Hylaosaurus has not been made known like the Megalosaurus, from 
detached parts of the skeleton successively discovered and analogically re- 
composed, but was at once brought into the domain of Palaeontology by the 
discovery of the following parts of the skeleton in almost natural juxtaposi- 
tion : viz. the anterior part of the trunk, including ten of the anterior ver- 
tebrae in succession, supporting a small fragment of the base of the skull ; 
the two coracoids, the coracoid extremities of both scapulae, detached verte- 
brae, several ribs more or less complete, and some remarkable parts of the 
dermal skeleton, including, apparently, enormous vertical plates or spines, ar- 
ranged, as is supposed, in the form of a median dorsal ridge or crest of sin- 
gular dimensions. 

In the fragment of the cranium may be distinguished the pterygoid ele- 
ments of the sphenoid bone, the inner margins of which touch anteriorly and 
then recede as they pass backwards, leaving a heart-shaped posterior nasal 
aperture, the apex of which is turned forwards. The breadth of this aper- 
ture is 1 inch 3 lines : its posterior position gives another character, by which 
the present Dinosaur, and probably the larger genera of the same order, re- 
sembled the Crocodiles more than the Lizards. 

The bodies of the vertebrae are shorter in proportion to their breadth than 
in the Megalosaurus or Iguanodon. They have not so smooth and polished 
a surface as in the Megalosaurus, nor are they so contracted in the middle, 
or so regularly rounded below from side to side ; a few of the anterior ver- 
tebrae are somewhat flattened below, so as to present an obscurely quadrate 
figure ; most of the anterior dorsals are more compressed and keel-shaped 
below : the sacral and caudal vertebrae are longitudinally sulcated at their 
under surface. 

The structure of the atlas and axis cannot be discerned in the Mantellian 
specimen ; the second (conspicuous) cervical vertebra has its sides subcom- 
pressed, its under surface flattened, and the anterior part of the slight angular 
ridges separating it from the concave lateral surfaces, are produced anteriorly 
into two feebly-marked tubercles. The inferior transverse processes are deve- 
loped from each side of the anterior jjart of the body of the vertebra ; they 
are subcircular, very slightly prominent, about 7 lines in diameter. 

In the fourth (conspicuous) vertebra, a large proportion, but not the whole, 
of a costigerous transverse process is developed from each side of the anterior 



112 REPORT 1841. 

part of the body, with the costal surface directed obliquely outwards and for- 
wards. There is a small costal surface at the side of the expanded posterior 
extremity of the same vertebra, against which a part of the head of the fourth 
rib abuts ; that and three of the succeeding ribs having their heads applied 
over the interspace of two contiguous vertebrae, as nearly throughout the tho- 
racic region in Mammalia. The lateral compression of the centrum increases 
in the sixth and seventh (conspicuous) vertebrae, in which the under surface 
forms an obtuse ridge ; in the eighth vertebra this surface is broader. In 
none of these vertebrae is a process developed from the under surface as in the 
hinder cervical and anterior dorsal vertebrae of the Crocodiles. 

The most striking character of the vertebrae of the Hylaosaurus is the 
great development of the neural arch and its processes. The anterior articu- 
lar processes extend (in the anterior dorsal and cervical vertebra) over half 
the centrum next in front, and a broad upper transverse process is developed 
from the side of the neurapophysis and along its anterior continuation : this 
transverse process extends horizontally outwards, is notched anteriorly, and 
contracts to an obtuse point against which the tubercle of the rib articulates : 
the transverse processes are flat transversely, slightly concave lengthwise, and 
smooth below : they increase in length and strength as the vertebrae extend 
along the trunk ; and the ribs, which they contribute to support, exhibit a still 
more rapid increase : the ribs present, as in the other Dinosaurs and Croco- 
diles, a bifurcated vertebral end for the double articulation above described*. 
The neck and head of the rib corresponding with the seventh conspicuous ver- 
tebra is 2 inches 2 lines in length ; the tubercle, or upper head, is 10 lines long ; 
the breadth of the rib at the point of bifurcation is 1 inch 1 line. The neck 
of the eighth rib has the same length as that of the seventh, but is twice as 
thick and strong ; the tubercle is broader but shorter. Beyond the tubercle 
the shaft of the rib is bent at right angles with the neck. This soon begins to 
shorten, and the shaft of the rib to lengthen, until it becomes attached solely 
to the transverse process. 

In the dorsal vertebrae the body increases in all its proportions, excepting 
its length. The lateral compression now manifests itself at the upper part 
of the centrum just below the neurapophysial suture ; the under surface of 
the posterior dorsal and lumbar vertebra is convex transversely, but in a less 
degree than in the Megalosaurus, and in some, it is obscurely carinated. The 
external surface at the middle contracted part of the vertebra is moderately 
smooth, but the minute striee give it a somewhat silky lustre ; it is longitu- 
dinally but irregularly ridged and grooved near the articular ends. These 
are both slightly concave at the centre, more slightly convex near the circum- 
ference. The difference between the vertebrae of the Hylaeosaur and the bi- 
concave Crocodilian vertebrae is chiefly manifested in the development of 
the neural arch. The modification of this part in the cervical vertebrae has 
already been mentioned. In the dorsal vertebrae each neurapophysis rises 
vertically, contracting in the axis of the vertebra, expanding transversely or 
outwardly, until it has attained a height equal to that of the centrum ; there it 
expands into a broad and flat platform, from the middle line of which the 
broad spine is developed. A vertically compressed but sti'ong transverse pro- 

* Dr. Mantell, io his Memoir on the Tilgate Saurians, Philos. Transactions, Part ii. for 1841, 
which I received while this Report was going through the press, says that " the hilobed head 
and the great external expansion of the arch of the rib in all probability bears a relation to 
the enormous development of the dermal spines," p. 143. But this is precisely the modifica- 
tion of the skeleton in which the Hylaosaurus differs most from the existing Saurians which 
possess such spines, as the Cyclura, and in which it most resembles the Iguanodon and Me- 
galosaurus. 



ox BRITISH FOSSIL REPTILES. 113 

cess is developed from the side of the neurapophysis, and is supported by a 
pyramidal underprop, extending upwards and outwards from the anchylosed 
base of the neurapophysis. There is a large, deep and smooth depression on 
each side of the base of the transverse process. Tlie anterior surface of the 
neural arch, above the anterior oblique processes, is traversed by a vertical 
ridge, on each side of which there is a shallow depression*. The spinous 
process is of unusual thickness, its transverse breadth at the base measures 
1 inch : this modification may probably relate to the support of great dermal 
spines. The spinal canal in the dorsal vertebrae is cylindrical, and expanded 
at both extremities ; its diameter at the middle is 7 lines, at the expanded out- 
lets 10 lines, in a posterior dorsal or lumbar vertebra. Here the bases of the 
neurapophyses begin to shorten, and leave a small proportion of the upper 
surface of the centrum uncovered at both ends, chiefly at the posterior end. 
The following are dimensions taken from three of the vertebrae of the Hy' 

IcEQsaurus: — Second Fourth n/ij.i 

Middle 
conspicuous conspicuous . , 

_ • 1 • 1 dorsal, 

cervical. cervical. 

In. Lin. In. Lin. In. Lin. 

Antero-posterior diameter of body . 1 10 2 2 2 9 

Vertical diameter of its articular end 16 2 6 

Transverse diameter of its articular end 2 2 2 3 

Transverse diameter of middle of body 2 

The differences between the vertebras of the Hijlceosaurus and Megalo- 
saurus have been already pointed out, and are further shown in the admea- 
surements given above : the vertebrae of the HylcBosaurus differ from those 
of the Iguanodon in their greater transverse diameter, and in the breadth of 
their under part ; those of the Iguanodon are flatter vertically along their 
whole sides, which converge to a narrower ridge at the under part. The 
vertebrae of the Hylceosaurus differ from those of the Streptospondylus in 
the sub-biconcave character of the articular ends of the centrum, and in its 
comparative shortness and thickness : the separated neural arch might be 
distinguished from that of the Streptospondylus by the simplicity of the sup- 
porting buttress of the transverse process; and, although equal in height, yet it 
is superior in the expansion and strength of the platform and spinous process. 

Sacrum, — There is a portion of a sacrum of a small or young Dinosaur 
(No. 2484> Mantellian Collection), which, in the form and proportions of the 
bodies of the vertebrae, most resembles the present genus, and cannot be re- 
ferred to Megalosaurus or Iguanodon. It includes two entire and parts of 
two other vertebral bodies, anchylosed together, and to the bases of the neu- 
rapophyses ; which, as in the Megalosaurus, are transferred to the upper and 
lateral 2)arts of the interspaces of the subjacent bodies. These are moderately, 
but regularly, contracted in the middle and chiefly laterally, being more flat- 
tened below, where likewise each is traversed by a longitudinal sulcus. At 
the middle of each lateral concavity there is a vascular perforation. I am 
uncertain which is the anterior part of this interesting series ; but, by the 
analogy of the Megalosaurus, conclude that vertebra which supports the great- 
est proportion of its neural arch, to be posterior to the adjoining one which 
supports the remaining small proportion. On this basis also 1 assume that the 
anterior sacral vertebra is deficient, if we may allow five to the Hylaeosaur us 
to the other Dinosaurs. 

The second sacral vertebra, then, is here broken across the middle of the 

* This description is taken from Nos. 2586 and 2125, parts of tlie same vertebra iu the 
Mantellian CoUectiou. 

1841. 1 



114 REPORT — 1841. 

body, exposing its solid minutely cellular central structure : its neural arch 
is too mutilated for profitable description : its base rests nearly equally on 
the second and third sacral bodies. The third neural arch, which exhibits 
a similar relative position, has its base extended half -way down the inter- 
space ; its strong transverse process extends outwards and forwards, and is 
at first contracted, then expands both transversely and vertically, juost so in 
the latter direction, and is twisted obliquely, so that the lower end is directed 
downwards and forwards, and the upper and thicker end is bent obliquely 
backwards, until it meets and becomes anchylosed to the anterior production 
of the transverse process of the next vertebra behind : an elliptical space is 
thus produced, the axis of which is nearly vertical, and into this space the 
neui'al canal opens ; the nerve being transmitted over the middle of the body 
of the vertebra, as in the sacrum of the Megalosaurus. 

The upper and inner part of the base of the broad, oblique transverse pro- 
cess, or sacral rib, abuts against the base of the spinous process. There is 
no appearance of accessory spines, such as the sacrum of the Megalosaurus 
is complicated with. 

The following are admeasurements of the present portion of the sacrum of 

the HylcEOsaurus : — 

In. Lin. 
Length of the body of the third vertebra ......:. 2 

Breadth of its articular end 2 

Breadth of its middle part 1 4 

Breadth of its inferior groove 4 

Length of the transverse process .1 10 

Antero-posterior diameter of the middle of process 4 

Vertical diameter of base of process 1 6 

Vertical diameter of expanded extremity 3 

From the lower part of centrum to the origin of the spinous process 2 6 
The spines appeal- to be anchylosed into a continuous ridge. 
The anterior surface of the transverse process appears undulated by wide 
shallow depressions and intervening elevations. 

Caudal vertebra. — A proportion of the tail, to the extent of nearly six feet, 
and including about twenty-six vertebrae, discovei-ed in a quarry in Tilgate 
Forest in the year 1837? is preserved in the Mantellian Collection. The 
transverse processes present almost Crocodilian proportions, in regard to their 
length, at the anterior part of this series, and may be discerned, though dimi- 
nished to mere rudiments, in the small terminal vertebrae of the series. In 
the most perfect of the anterior vertebrae they are compressed vertically, but 
with convex, not flattened sides, and rounded edges, presenting an elliptical 
transverse section, and preserving the same breadth to their truncated extre- 
mity : they extend outwards, and are slightly bent forwards : the breadth of 
this vertebra between the extremities of the transverse processes is 11 inches. 
The neurapophysis is curved forwards from the base of the transverse process 
to form the anterior oblique process ; its length from the extremity of this 
process to that of the posterior one is 3^ inches. The neurapophysis presents 
a simple convex external surface to the base of the spine : the antero-poste- 
rior extent of this process is two inches. The chevron bones are from four 
to five inches in length near the base of the tail ; they may be distinguished, 
like the transverse processes, by their convex external surface ; their base is 
open, not confluent as in the Iguanodo7i, and articulated to two distinct tu- 
bercles. Between these tubercles, which are placed at each end of the under 
surface of the centrum, there is a longitudinal sulcus. The transverse pro- 
cesses soon lose the slight anterior curve, stand straight out, decrease in 



ON BRITISH FOSSIL REPTILES. 115 

length, and descend from the neurapophysis to the centrum as the vertebrs 
approach the end of the tail. 

The chevron bones also decrease in length, but they expand in the antero- 
posterior direction at their unattached and dependent extremity, M'hich is 
defined by a slight convex outline. The following admeasurements give the 
rate of decrease in length in the caudal vertebras, taken at intervals of six 
joints : — In. Lines. 

Length of body of presumed 8th caudal 2 6 

Length of body of presumed 14th caudal 2 ^ 

Length of body of pi-esumed 20th caudal 2 2 

The sides of the slender posterior vertebrae are distinguished by a slight 
median expansion below the base of the rudimental transverse jDrocess, so that 
the surface, instead of being gently concave lengthwise, undulates by virtue 
of the middle elevation. I have not met with this character in the corre- 
sponding vertebrae of other Saurians. In the vertical direction the sides of 
the centrum in the posterior caudals converge at almost a right angle to the 
inferior groove. The greater breadth of the centrum, in proportion to its 
height, may still be discerned in the terminal caudal vertebrae : thus in the 
centrum 2 inches 2 lines long, the breadth was 1 inch 10 lines, and the 
height only 1 inch 3 lines. 

Dermal scutes. — Unequivocal evidence that a dermal skeleton, analogous 
to that in the recent Crocodiles, was developed in the Hylceosaurus, was af- 
foi'ded by the discovery of bony scutes in the mass of vegetable matter re- 
moved in clearing the portion of the skeleton first described. Some of these 
detached bony plates still adhere to the caudal vertebrae, and may be observed 
to decrease in size as they approach the end of the tail. From their form, 
which is elliptical or circular, and from the absence of any surface indicating 
the overlapping of an adjoining scute, it may be inferred, that the bony 
plates in question studded in an unconnected order the skin of the Hylaeo- 
saur. The diameter of the largest of these scutes does not exceed three 
inches ; the smallest present a diameter of one inch. They are flat on the 
under surface, convex with the summit developed into a tubercle in the smaller 
specimens, but which is less prominent in the larger ones : the outer surface is 
studded all over by very small tubercles : the inner surface presents the fine 
decussating straight lines, already noticed in the scutes of the Goniopholis. 

By the kindness of Dr. Mantell, I have been favoured with the means of 
submitting the structure of a dermal scute to microscopical examination. 

The medullary canals, which are stained brown, as if with the hematosine 
of the old reptile, differ from those of ordinary bone in the paucity or absence 
of concentric layers. They are situated in the interspaces of straight opake 
decussated filaments, which frequently seem to be cut short off close to the 
medullary canals. Very fine lines may be observed to radiate from some of 
the medullary canals : irregularly shaped, oblong and angular radiated cells 
are scattered through most parts of the osseous tissue, but they present less 
uniformity of size than do the Purkinjian cells in ordinary bone. The most 
striking characteristics of the dermal bone are the long straight spicular fibres 
which traverse it, and decussate each other in all directions, representing, as 
it seems, the ossified ligamentous fibies of the original corium. 

Dermal spines? — On the left side of the thorax, partly overlying the left 
scapula and vertebral ribs, in the large slab of stone containing the anterior 
part of the skeleton, there are some large elongated, flattened pointed plates 
of bone, three of which seem to follow each other in natural succession. The 
length of the first of these plates is seventeen inches, the breadth of the base 
five inches, equal to the antero-posterior diameter of two vertebrae : they de- 

i2 



116 REPORT — 1841. 

crease somewhat rapidly in length, the second being fourteen inches long and 
the third eleven inches long ; but slightly increase in breadth. 

These remarkable bones are regarded by Dr. Mantell* as having formed 
part of a serrated fringe extended along the back of the animal, analogous to 
that of the Cycliira Lizard. This ingenious suggestion carries with it so 
high a degree of probability, that I had not thought of comparing the bones 
in question with any other part of the skeleton, until my attention was arrested 
by observing a want of symmetry in the form of the most perfect of them. 
They are nearly flat, but along the middle present a slight degree of conca- 
vity towards the observer, which, however, may be paralleled by a similar con- 
cavity on the opposite side buried in the stone ; but the anterior or convex 
margin inclines from the middle line towards the concave side. With regard 
to their relative position to the rest of the skeleton, it must be observed that 
the ventral surface of this is exposed ; so that the under parts of the bodies of 
the vertebrae are towards the observer, and their spines imbedded in the matrix. 
The coracoid and scapular arch are placed, as might be expected in a ske- 
leton little disturbed and lying on its back, with their under surfaces towards 
the observer, and covering, like a buckler, a portion of the vertebrae and ribs. 
In this position we might look for a portion of the apparatus of the sternal or 
abdominal ribs, in the hope of discerning the modifications of these variable 
parts which might characterize a genus differing in many peculiarities from 
other known Saurians. Now it is with the apparatus of abdominal ribs, which 
present such a diversity of characters in other Saurians, that it may be use- 
ful to compare the long flattened bones in question, as well as with the sup- 
porting bones of a dorsal crest, in the event of a future discovery of a skeleton 
or portion of skeleton of the Hylceosaurus including these bones. The objec- 
tion to their being abdominal ribs, which may be founded on their great rela- 
tive breadth as compared with those ribs in other Saurians, and especially 
with the vertebral ribs of the Hylceosaiirus itself, deserves due consideration ; 
but the same objection applies to the bones in question as compared with the 
superadded spines in the Lizard with a dorsal ft-inge, or with the spines of the 
vertebrte themselves in the HylcBosaiirus. For the dorsal dermal spines in 
the Cyclura correspond in number with the spines of the vertebrae which sup- 
port them, while the base of each of the hypothetical dermal spines of the Hy- 
laeosaur extends over more than two vertebrae. 

In the Monotremata ( Ornithorhynchus and Echidna) the abdominal ribs 
are as much broader than the vertebral ribs as they would be in the Hylcco- 
saurus, on the costal hypothesis of the detached bony plates here suggested ; 
and, after the close repetition, in the Ichthyosaurus, of another of the remarka- 
ble deviations in those aberrant Mammals from the osteological type of their 
class, viz. in the structure of their sternal and scapular arch, the reappearance 
of the inonotrematous modification of the sternal ribs in the present extinct 
reptile would not be surprising. The want of symmetry and the difference of 
size and form, above aUuded to, in the four succeeding spine-shaped plates, 
agree better with the costal than the spinous hypothesis. 

Whether the bones in question be dorsal spines or abdominal ribs, they 
have evidently been displaced from their natural position in the partial disar- 
ticulation of the entire skeleton prior to its immersion in the mud that has 
been subsequently hardened around it; but the degree of displacement has 
not been greater in the one case than in the other. 

In offering, witii due diffidence, a choice of opinions respecting the nature 
of these singular bones, I have been actuated solely with the view of accele- 
rating the acquisition of the true one, which, it is obvious, will be more likely 
* Geology of South-east of England, p. 323. Wonder* of Geology, vol. i. p. 402. 



ON BRITISH FOSSIL REPTILES. Il7 

to be attained by the choice being present to the mind of subsequent fortu- 
nate discoverers of these remains of the Hylceosaurus, than if they were solely 
preoccupied by the hypothesis of the dorsal fringe. For example, it may lead 
to more careful noting of the constancy or otherwise of the unsymmetrical in- 
clination of the convex margin of the spine, and whether they form, or are 
disposed in, pairs ; which, on the costal hypothesis, may be expected, in the 
event of another skeleton being discovered. 

Bones of the Extremities. 

Scapular arch. — The scapula of the Hylceosaurus* is longer and narrower 
than in the Monitors and Iguanas, adhering in this respect to the Crocodilian 
type, but most resembling in the shape of its blade or body, that of the genus 
Scincus. It differs, however, from the scapulae of all known reptiles, and 
indicates an approach to the Mammalian type, by the production of a strong 
obtuse acromial ridge, separated by a deep and wide groove from the hume- 
ral and coracoid articular surfaces. The blade of the scapula is long, flattened, 
slightly convex on the inner and proportionally concave on the outer sur- 
face : the anterior margin is convex, the posterior one concave ; the upper 
extremity or base truncate, slightly convex, with the posterior angle a little 
produced, the anterior angle rounded off. On the outer side of the scapula 
two broad convex ridges descend and converge to form the beginning of a 
thick and strong spine, at fourteen inches distance from the base ; this then 
expands into the thick acromial ridge, which extends transversely, and is con- 
tinued forwards as a long subprismatic process from the anterior angle of 
the head of the scapula. This process, which appears likewise to be present 
in the scapula of the Iguanodon, perhaps also in the Megalosaurus, is broken 
off in the present specimen about four inches from the neck of the scapula, 
with which it forms a right angle. The acromion is perforated at the base of 
its anterior prolongation by a foramen analogous to the supraspinal one in the 
scapula of the Edentate Mammalia. Besides the scapulae preserved in the 
connected part of the skeleton, there is, in the Manteliiau Museum, a nearly 
entire and detached scapula of larger size, discovered, in connexion with many 
other bones of the skeleton, in a layer of blue clay near Bolney in Sussex, 
and indicating the connected part of the skeleton first discovered in 1832 to 
have belonged to an immature individual. The dimensions of this scapula 
ai"e as follows : — In. Lines. 

Length of the scapula 18 

Breadth of its base 8 

Breadth of its neck 3 9 

Thickness of its base 1 

Thickness of its neck 2 6 

Breadth of subacromial groove 2 

Breadth of humeral articulation 4 

Breadth of coracoid articulation 2 6 

The coracoids present a much more simple form than in the Megalosaurus, 
and resemble those of the Scink and Chameleon, thus deviating in their great 
breadth, like the coracoids of the Enaliosaurs, from the Crocodilian type. In 
the portion of the skeleton the right coracoid is slightly bent out of place and 
thrust under the left one ; and there is no trace of a sternal or entosternal bone 
in their interspace. The median margin of the coracoid describes an unin- 

* I have been favoured by Dr. Mantell vrith a drawing of the scapula figured by him in his 
recent Meuioii- on ihe Hylceosaurus, Phil. Trans., 18tl, pi. x. fig. 10. The description above 
given of this, as of all the other Tilgate Saurians in the present Report, is taken from the 
original specimens in the British Museum, and other depositories of the Wealden fossils. 



118 REPORT — 1841. 

terrupted and full convex curve commencing at the angle dividing it from the 
scapular articular surface ; but it is separated by a concavity or emargination 
from tiie articular surface for the humerus. It is perforated by a moderate 
sized elliptical canal, about two inches from the humeral articulation, and in 
this respect resembles the same bone in the Iguana, Monitors and Lizards, 
and differs from the Scinks and Chameleons. The antero-posterior extent of 
the coracoid in the connected portion of skeleton is eight inches ; its trans- 
verse diameter five inches. 

A humerus, and a phalangeal bone found with the scapula, near Bolney, 
are figured by Dr. Mantell in the Memoir of 184'1. 

Tteth of the Hylccosaur ? — With regard to the Hylceosaurus Dr. Mantell ob- 
serves, in his latest geological work, " the teeth are unknown ; but in the quar- 
ries where the bones of that reptile were discovered, I have found teeth of a 
very peculiar form, which appear to have belonged to a reptile, and are en- 
tirely distinct from those of the Megalosaurus, Iffuanodon,Crocodi\e and Ple- 
siosaurus, whose remains occur in the Tilgate strata*." The form and struc- 
ture of these teeth, which will be presently described, deviate too much from 
those of the Crocodilian family to make at all probable a reference of them 
to the genera Poikilopleuron, Streptospondylus, or Cetiosaur, which are much 
more closely allied to the Crocodilians than is the Hylseosaur. In the 'Geology 
of the South-east of England,' Dr. Mantell attributes these teeth, on the author- 
ity of M.Boue, to the Cylindricodon, a name by which Dr. Jager distinguishes 
one of the species of his genus ^Phyiosaurus.' I have been favoured by Dr. Jager 
with one of the bodies supposed to be the teeth of the Cylindricodon of the 
Wirtemberg Keuper, but it is merely the cast of a cylindrical cavity, consist- 
ing entirely of that mineral substance, without a trace of dental structure. 
The difference of form between the Wealden teeth now under consideration, 
and those on which the Phytosaurus cylindricodon of Jager was founded, is 
pointed out in detail in my Odontography, and has been likewise appreciated 
by the estimable Palaeontologist, M. Fischer de Waldheim, by whom their re- 
semblance to certain Saurian teeth from the Ural Mountains, belonging to the 
genus Rhopalodon\, is indicated. From these teeth, however, the presumed 
Hyteosaurian teeth differ in having thick and flat instead of serrated coronal 
margins. The following is Dr. Mantell's original description of the teeth in 
question : — 

" These teeth are about an inch and a quarter in length, and commence 
with a subcylindrical shank, which gradually enlarges into a kind of shoulder, 
terminating in an obtuse angular apex, the margins of which are more or less 
worn, as if the teeth had been placed alternately so as to meet at their edges, 
as in pi. ii. fig. 3. They are obscurely striated longitudinally, and have a 
thick coat of enamel : the crown of the tooth is solid, but the shank is more 
or less hollow. All the specimens appear as if they had been broken off" close 
to the jaw; but they may have been separated by necrosis occasioned by the 
pressure of the supplementary teeth J." 

The following is the result of a microscopical examination of these teeth. 
The tooth consists of a body of dentine covered by a thick coating of clear 
structureless enamel, and surrounding a small central column of true bone, 
consisting of the ossified remains of the pulp, which presents the usual cha- 
racters of the texture of the bone in the higher reptiles. The dentine differs, 
like that of existing Lacertians, from the dentine of the Iguanodon in the en- 
tire absence of the numerous medullary canals which form so striking a cha- 

* Wonders of Geology, vol. i. p. 403. 

•f- Lettre siir le Rhopalndoyi, Moscow, Svo, 1841. 

X Geology of the South-east of England, p. 293. 



ON BRITISH FOSSIL REPTILES. 119 

racteristic of the more gigantic Wealden reptile. The main calcigerous tubes 
are characterized by the slight degree of their primary inflections ; they are 
continued in an unusually direct course from the pulp-cavity to the outer sur- 
face of the dentine, at nearly right angles with that surface, but slightly in- 
clined towards the expanded summit of the tooth. They are chiefly remarka- 
ble for the large relative size of their secondary branches, which diverge from 
the trunks in irregular and broken curves, the concavity being always to- 
wards the pulp-cavity. In most parts of the tooth, the number of these 
branches obscures even the thinnest sections. 

The ossified pulp exhibits the parallel concentric layers of the ossified mat- 
ter surrounding slender medullary canals, and interspersed with irregular el- 
liptical radiated cells. 

Jaw of the Hylceosaurus? — No.g^^^s' i" *^^^ Mantellian Collection, is a por- 
tion of the right ramus of the lower jaw, with characters distinguishing it from 
that of any other known Saurian; as, for example, its degree of curvature, in- 
dicating the lower jaw to have been bent down in an unusual degree, and the 
remarkable inequality of its external surface. This fragment is about three 
inches long, one inch seven lines deep at the hind part, and one inch five lines 
deep at the fore-part ; flattened and smooth at the inner side, but having the 
outer side raised by the termination of a strong angular ridge at its lower and 
hinder part, and by a rough convex longitudinal ridge extending along its 
upper part ; the surface of the jaw being concave above and below this ridge. 
The lower margin is thick and convex ; the upper one is formed by a regular 
series of pretty close-set sockets, with the internal alveolar wall broken away, 
displaying their partitions ; but with the outer wall entire, thin and slightly 
crenate at its upper margin. 

At the hind part of tliis fragment the anterior extremity of the opercular 
piece is preserved ; the rest is formed exclusively by the dentary piece : the 
area of the wide conical cavity in the interior of the jaw is exposed at the 
back part of the fragment ; its apical termination is near the fore part. A 
succession of large vascular canals open obliquely forwards in the concavity 
above the upper oblique longitudinal ridge. The whole of the outer surface 
is minutely ridged and punctate. 

The depth of the sockets bears a smaller proportion to that of the jaw than 
in modern Lacertians or Crocodiles, being about one-fourth of that depth : 
the partitions of the sockets, which are very regular in their breadth and 
depth, though they are more prominent than in the pleurodont Lizards, yet 
exhibit a fractured margin ; there is no trace of a smooth natural surface of 
the bone in the interspace of the sockets; and at the part where the inner 
wall has been least mutilated, it nearly completes the socket and incloses the 
long and slender fang of the tooth. Whence, I conclude, that the entire jaw 
of the extinct reptile would have exhibited a series of true sockets, not de- 
pressions merely, as in the pi'esent mutilated fragment, and that it would 
have agreed with the Megalosaurus in presenting the thecodont mode of at- 
tachment of the teeth. 

The crowns of all the teeth are broken off"; the small sockets of reserve, 
exposed at the inner side of the base of the old sockets, do not contain any 
evidence of the species to which this fossil has belonged. In the absence of 
this characteristic part of the tooth, an element in guiding our choice between 
the Iguanodon and HylcEosuurus is given by the breadth of the interspaces 
of tiie sockets ; these must bear relation to the breadth of the crowns of the 
teeth, if we suppose that they were in contact throughout the series, as in 
Lacertians. Now the teeth of the Iguanodon, and those which I have re- 
ferred to the HylcEosaurus, diff"er in a marked degree in the breadth of the 



120 REPORT — 1841. 

crown. The complicated and expanded crown of the Iguanodon's tooth is 
supported on a narrower stem ; and the stems or fangs, if the crowns were 
in contact without overlapping, must have been separated by interspaces of 
proportional breadth, viz. twice their own breadth ; but the thickness of the 
crown of the tooth of the Iguanodon renders it very unlikely that they did 
overlap each other. Now the crowns of the teeth of the Hylaeosaur are ex- 
panded to such an extent, as, if in contact to require an interspace of the fangs, 
not broader than the fangs themselves; and the interspaces of the fangs in 
the fragment of jaw under consideration correspond with crowns of this 
breadth. The fangs of the teeth in the Iguanodon are conical, and more or 
less angular ; in the teeth presumed to belong to the Hyleeosaur the fangs are 
cylindrical ; the sockets in the present fragment correspond with the latter 
form. 

In my Odontography*, I adopted the opinion of Dr. Mantellf respecting 
the present fossil ; but subsequent examination and consideration of its cha- 
racters have led me to a different conclusion. It might, nevertheless, be 
urged that the teeth of the young Iguanodon may exhibit such modifications 
as would affect the validity of the objections here offered ; but these, I think, 
establish the greater probability that the jaw in question originally contained 
teeth of the form of those that I have referred to the HyloEosaurus. 

The remains of the Hylaosaurus have been discovered in the Wealden 
formation in the following localities : Tilgate Forest, Bolney and Battle. 

Iguanodon Mantelli, Cuv. 

The bones of an enormous reptile, successively discovered in tho Wealden 
strata by Dr. Mantell, interpreted by their discoverer with the aid of Cuvier 
and CliftJ, named Iguanodon by Conybeare§, lastly found in juxtaposition 
to the extent of nearly half the skeleton, in the green-sand quarries of Mr. 
Benstead, offer not the least marvellous or significant evidences of the inha- 
bitants of the now temperate latitudes during the earlier oolitic periods of the 
formation of the earth's crust. 

With vertebrae subconcave at both articular extremities, having, in the 
dorsal region, lofty and expanded neural arches, and doubly articulated ribs, 
and characterized in the sacral region by their unusual number and compli- 
cation of structure ; with a Lacertian pectoral arch and unusually large bones 
of the extremities excavated by large medullary cavities and adapted for ter- 
restrial progression ; — the Iguanodon was also distinguished by teeth, resem- 
bling in shape those of the Iguana, but in structure difiering from the teeth of 
every other known Reptile, and unequivocally indicating the former existence, 
in the Dinosaurian Order, of a gigantic representative of the small group of 
living lizards which subsist on vegetable substances. 

Of this remarkable Reptile, the results of personal examination of almost 
a'l the recognisable remains that have hitherto been collected in public or pri- 
vate museums, are here given. 

Teeth. — The value of the ordinary external characters of the teeth of the 
oviparous Vertebrata has never perhaps been placed in so striking a point of 
view as in the leading steps to the discovery of the Iguanodon, which cannot 
be better recounted than in the words of Dr. Mantell. 

* Part ii. p. 24S. f Wonders of Geology, vol. i. p. 393. 

% See Philosophical Transactions, 1825, "Notice on the Iguanodon, by Gideon Mantell, 
F.L.S." 

§ " The name Iguanodon, derived from the form of the teeth (and which I have adopted 
at the suggestion of the Rev. VV. Conybeare), will not, it is presumed, be deemed objection- 
able." — Loc. cit. 



ON BRITISH FOSSIL REPTILES. 121 

After noticing the ordinary organic remains whicli characterize the sand- 
stone of the Tilgate Forest, and his discovery, in the summer of 1822, of other 
teeth distinguished by novel and remarkable characters, the indefatigable ex- 
plorer of the Wealden proceeds to state*, — 

" As these teeth were distinct from any that had previously come under my 
notice, I felt anxious to submit them to the examination of persons whose 
knowledge and means of observation were more extensive than my own. I 
therefore transmitted specimens to some of the most eminent naturalists in 
this country and on the continent. But although my communications were 
acknowledged with that candour and liberality which constantly characterizes 
the intercourse of scientific men, yet no light was thrown upon the subject, 
except by the illustrious Baron Cuvier, whose opinions will best appear by the 
following extract from the correspondence with which he honoured me : — 

" ' Ces dents me sont certainement inconnues ; elles ne sont point d'un ani- 
mal carnassier, et cependant je crois qu'elles appartiennent, vu leur peu de 
complication, leur dentelure sur les bords, et la couche mince d'email qui les 
revet, a I'ordre des reptiles ; a I'apparence exterieure on pourrait aussi les 
prendre pour des dents de poissons, analogues aux tetrodons, ou aux diodons; 
mais leur structure interieure est fort difFerente de celles-la. N'aurions-nous 
pas ici un animal nouveau, un reptile herbivore ? et de meme qu'actuelle- 
ment chez les mammiferes terrestres, c'est parmi les herbivores que Ton trouve 
les especes a plus grande taille, de meme aussi chez les reptiles d'autrefois, 
alors qu'ils etaient les seuls animaux terrestres, les plus grands d'entr'eux ne 
se seraient-ils point nourris de vegctaux ? Une partie des grands os que vous 
possedez appartiendrait a cet animal unique, jusqu'a present, dans son genre. 
Le temps cowfirmera ou iwfirmera cette idee, puisqu'il est impossible qu'on ne 
trouve pas un jour une partie de la squelette reunie a des portions de ma- 
choires portant des dents. C'est ce dernier objet surtout qu'ij s'agit de re- 
chercher avec le plus de perseverance.' 

" These remarks," Dr. Mantell proceeds to say, " induced me to pursue my 
investigations with increased assiduity, but hitherto they have not been at- 
tended with the desired success, no connected portion of the skeleton having 
been discovered. Among the specimens lately collected, some, however, 
were so perfect, that I resolved to avail myself of the obliging oifer of Mr. 
Clift (to whose kindness and liberality I hold myself particularly indebted), 
to assist me in comparing the fossil teeth with those of the recent Lacertae in 
the Museum of the Royal College of Surgeons. The result of this examina- 
tion proved highly satisfactory, for in an Iguana which Mr. Stutchbury had 
prepared to present to the College, we discovered teeth possessing the form 
and structure of the fossil specimens." 

The important difference which the fossil teeth presented in the form of 
their grinding surface was afterwards pointed out by Cuvierf , and recognised 
by Dr. Mantell J, and the combination of this dental distinction with the ver- 
tebral and costal characters, which prove the Iguanodon not to have belonged 
to the same group of Saurians as that M'hich includes the Iguana and other 
irvodern lizards, rendered it highly desirable to ascertain, by the improved 
modes of investigating dental structure, the actual amount of correspondence 
between the Iguanodon and Iguana in this respect. This I have endeavoured 
to do in my general description of the Teeth of Reptiles §, from which the 
following account is abridged. 

* Notice on the Iguanodon, Phil. Trans. 1825. 

t Ossemens Fossiles, 1824, vol. v. part ii. p. 351. 

X Illustrations of the Geology of Sussex, 4to, 1827. 

§ Odontography, part ii. p. 249; and Transactions of the British Association, 1838. 



122 REPORT— 1841. 

The teeth of the Iguaiiodon, though resembling most closely those of the 
Iguana, do not present an exact magnified image of them, but differ in the 
greater relative thickness of the crown, its more complicated external surface, 
and, still more essentially, in a modification of the internal structure, by which 
the Iguanodon equally deviates from every other known reptile. 

As in the Iguana, the base of the tooth is elongated and contracted, while 
the crown is expanded, and smoothly convex on the inner side ; when first 
formed it is acuminated, compressed, its sloping sides serrated, and its external 
surface traversed by a median longitudinal ridge, and coated by a layer of 
enamel, but beyond this point the description of the tooth of the Iguanodon 
indicates characters peculiar to that genus. In most of the teeth that have 
hitherto been found, three longitudinal ridges traverse the outer surface of 
the crown, one on each side of the median primitive ridge ; these are sepa- 
rated from each other and from the serrated margins of the crown by four 
wide and smooth longitudinal grooves. The relative width of these grooves 
varies in different teeth ; sometimes a fourth small longitudinal ridge is deve- 
loped on the outer side of the crown. The marginal serrations, which, at first 
sight, appear to be simple notches, as in the Iguana, present under a low mag- 
nifying power the form of transverse ridges, themselves notched, so as to re- 
semble the mammillated margins of the unworn plates of the elephant's grinder: 
slight grooves lead from the interspaces of these notches upon the sides of 
the marginal ridges. These ridges or dentations do not extend beyond the 
expanded part of the crown : the longitudinal ridges are continued further 
down, especially the median ones, which do not subside till the fang of the 
tooth begins to assume its subcylindrical farm. The tooth at first increases 
both in breadth and thickness ; it then diminishes in breadth, but its thick- 
ness goes on increasing ; in the larger and fully formed teeth, the fang de- 
creases in every diameter, and sometimes tapers almost to a point. The 
smooth unbroken surface of such fangs indicates that they did not adhere to 
the inner side of the maxillae, as in the Iguana, but were placed in separate 
alveoli, as in the Crocodile and Megalosaur : such support would appear, in- 
deed, to be indispensable to teeth so worn by mastication as those of the 
Iguanodon. 

The apex of the tooth soon begins to be worn away, and.it would appear, 
by many specimens, that the teeth were retained until nearly the whole of the 
crown had yielded to the daily abrasion. In these teeth, however, the deep 
excavation of the remaining fang plainly bespeaks the progress of the suc- 
cessional tooth prepared to supply the place of the worn out grinder. At the 
earlier stages of abrasion a sharp edge is maintained at the external part of 
the tooth by means of the enamel which covers that surface of the crown ; 
the prominent ridges upon that surface give a sinuous contour to the middle 
of the cutting edge, whilst its sides are jagged by the lateral serrations: the 
adaptation of this admirable dental instrument to the cropping and commi- 
nution of such tough vegetable food as the Clathrurice and similar plants, 
which are found buried with the Iguanodon, is pointed out by Dr. Buckland, 
with his usual felicity of illustration, in his ' Bridgewater Treatise,' vol.i. p. 246. 

When the crown is worn away beyond the enamel, it presents a broad and 
nearly horizontal grinding surface, and now another dental substance is brought 
into use to give an inequality to that surface ; this is the ossified remnant of 
the pulp, which, being firmer than the surrounding dentine, forms a slight 
transverse ridge in the middle of the grinding surface : the tooth in this stage 
has exchanged the functions of an incisor for that of a molar, and is prepared 
to give the final compression, or comminution, to the coar"sely divided vege- 
table matters. 



1 



ON BRITISH FOSSIL. REPTILES. 123 

The marginal edge of the incisive condition of the tooth and the median 
ridge of the molar stage are more effectually established by the introduction 
of a modification into the texture of the dentine, by which it is rendered softer 
than in the existing Iguans and other reptiles, and more easily Avorn aAvay : 
this is effected by an arrest of the calcifying process along certain cylindrical 
tracts of the pulp, which is thus continued, in the form of medullary canals, 
analogous to those in the soft dentine of the Megatherium's grinder, from the 
central cavity, at pretty regular intervals, parallel with the calcigerous tubes, 
nearly to the surface of the tooth. The medullary canals radiate from the in- 
ternal and lateral sides of the pulp-cavity, and are confined to the dentine 
forming the corresponding walls of the tooth : their diameter is f^th of an 
inch : they are separated by pretty regular intervals equal to from six to eight 
of their own diameters ; they sometimes divide once in their course. Each 
medullary canal is surrounded by a clear space ; its cavity was occupied in 
the section described by a substance of a deeper yellow colour than the rest 
of the dentine. 

The calcigerous tubes present a diameter of ^^^^ffli of an inch, with inter- 
spaces equal to about four of their diameters. At the first part of their course, 
near the pulp-cavity, they are bent in strong undulations, but afterwards pro- 
ceed in slight and regular primary curves, or in nearly straight lines to the 
periphery of the tooth. When viewed in a longitudinal section of the tooth, 
the concavity of the primary curvature is turned towards the base of the tooth : 
the lowest tubes are inclined towards the root, the rest have a general direc- 
tion at right angles to the axis of the tooth ; the few calcigerous tubes, which 
proceed vertically to the apex, are soon worn away, and can be seen only in 
a section of the apical part of the crown of an incompletely developed tooth. 
The secondary undulations of each tooth are regular and very minute. The 
branches, both primary and secondary, of the calcigerous tubes are sent off 
from the concave side of the main inflections ; the minute secondary branches 
are remarkable at certain parts of the tooth for their flexuous ramifications, 
anastomoses, and dilatations into minute calcigerous cells, which talce place 
along nearly parallel lines for a limited extent of the course of the main tubes. 
The appearance of interruption in the course of the calcigerous tubes, occa- 
sioned by this modification of their secondary branches, is represented by the 
irregularly dotted tracts in the figure. This modification must contribute, 
with the medullary canals, though in a minor degree, in producing that ine-. 
quality of texture and of density in the dentine, which renders the broad and 
thick tootli of the Iguanodon more efficient as a triturating instrument. 

The enamel which invests the harder dentine, forming the outer side of the 
tooth, presents the same peculiar dirty brown colour, when viewed by trans- 
mitted light, as in most other teeth : very minute and scarcely perceptible un- 
dulating fibres, running vertically to the surface of the tooth, is the only struc- 
ture I have been able to detect in it. 

The remains of the pulp in the contracted cavity of the completely formed 
tooth are converted into a dense but true osseous substance, characterized by 
minute elliptical radiated cells, whose long axis is parallel with tlie plane of 
tiie concentric lamellae, which surround the few and contracted medullary 
canals in this substance. 

The microscopical examination of the structure of the Iguanodon's teeth 
thus contributes additional evidence of the perfection of their adaptation to 
the offices to whicii their more obvious characters had indicated them to have 
been destined. 

To preserve a trenchant edge, a partial coating of enamel is applied ; and, 



124 REPORT — 1841. 

that the thick body of the tooth might be worn away in a more regularly ob- 
lique plane, the dentine is rendered softer as it recedes from the enameled 
edge by the simple contrivance of arresting the calcifying process along cer- 
tain tracts of the inner wall of the tooth. When attrition has at length ex- 
hausted the enamel, and the tooth is limited to its function as a grinder, a 
third substance has been prepared in the ossified remnant of the pulp to add 
to the efficiency of the dental instrument in its final capacity. And if the 
following reflections were natural and just after a review of the external cha- 
racters of the dental organs of the Iguanodon, their truth and beauty become 
still more manifest as our knowledge of their subject becomes more particu- 
lar and exact : — 

" In this curious piece of animal mechanism we find a varied adjustment of 
all parts and'proportions of the tooth, to the exercise of peculiar functions, 
attended by compensations adapted to shifting conditions of the instrument, 
during different stages of its consumption. And we must estimate the works 
of nature by a different standard from that which we apply to the productions 
of human art, if we can view such examples of mechanical contrivance, united 
with so much economy of expenditure, and with such anticipated adaptations 
to varying conditions in their application, without feeling a profound convic- 
tion that all this adjustment has resulted from design and high intelligence." 
— Buckland's Bridgewater Treatise, vol. i. p. 249. 

Head. — Two fragments of jaw with alveoli, in the Mantellian Collection, 
are referred by its founder to the Iguanodon : in neither of them, unfortu- 
nately, is a tooth with the characteristic crown preserved : the size of these 
specimens proves them to have belonged, if to this genus, then to young in- 
dividuals. The smaller fragment is described in this Report under the head 
of Hylceosaurus, on account of the cylindrical, equal, and straight form of the 
remaining fangs. These parts correspond with the fangs of the teeth which I 
suppose to belong to the Hylaosaurus, rather than with those of the Igua- 
nodon, which are angular, curved, taper towards a point, and support crowns 
so expanded, as to require greater intervals between their fangs than in the 
fossil. It is just possible that these differences may depend on age*. 

Tympanic hone. — A reptile with vertebrae and ribs resembling in their chief 
characters those of the ccelospondylian Crocodiles, and with distinctive pecu- 
liarities, in which the Lacertians by no means participate, might reasonably be 
conjectured to resemble the Crocodiles in the form of the tympanic bone ; and 
if the reptile in question used its teeth for masticating hard vegetable sub- 
stances, we might with more reason expect that the bony pillar supporting the 
lower jaw should be firmly and immoveably fixed through its whole length, like 
the tympanic bone of the Crocodilians, and not be loosely suspended to the skull 
by a single extremity, as in the Iguana and other Lacertians. A very remarkable 
bone discovered in the Tilgate strata, figured by Dr. Mantell in the ' Geology 
of the South-east of England,' pi. ii. fig. 5, the resemblance of which to the 
' OS quadratum,' or tympanic bone of birds, was first suggested by Dr. Hodg- 
kin, is assigned to the Iguanodon by Dr. Mantell. He accurately describes 
it " as forming a thick pillar or column, which is contracted in the middle, and 
terminates at both extremities in an elliptical and nearly flat surface." In the 
Iguana and other reptiles the lower end of the tympanic bone is terminated 
by a convex trochlea, which is received into a corresponding cavity in the 
lower jaw. Is the modification of the bone in question, assuming it to belong 

* In the Monitor-lizards of the modern genera Thorictes and Crocodilurus, the posterior 
teeth in the young indhiduals have more or less compressed and tri-cuspidate crowns, but 
in the old animals they have round obtuse crowns, adapted for true mastication. Some mo- 
dification analogous to this may take place in the Iguanodon. 



ON BRITISH FOSSIL REPTILES. 125 

to the Iguanodon, indicative of a peculiarity of the joint of the lower jaw as 
remarkable as the structure of the teeth, and correlated to their masticatory 
uses ? " Two lateral processes, or alcE, pass off obliquely, and are small in 
proportion to the size of the column; on placing these bones beside the os 
tympani of an Iguana, we at once perceive that the relative proportions of 
these parts are reversed ; for in the recent animal the pillar is small and the 
lateral processes large. From the great size of the body of the fossil, and the 
extreme thinness of its walls, the tympanic cellulcB must have been of consi- 
derable magnitude, and have constituted a large portion of the auditory cavi- 
ties. PI. ii. fig. 1., (fig. 5 is meant,) accurately represents the most perfect 
specimen in my cabinet ; it is 6 inches high, and 5| inches wide at the 
longest diameter of the extremity of the body. It exceeds in magnitude the 
corresponding bone of the Mosasaurus, and is fourteen times as large as the 
same bone in an Iguana 4 feet long." Loc. cit., p. 306. 

Vertebral Column. — The vertebrae of the Iguanodon have their bodies ter- 
minated by flat or slightly concave articular surfaces*, and their sides flat or 
slightly convex vertically, moderately concave lengthwise or in the axis of 
the vertebra ; the sides converge more or less towards the under surface, 
and the body accordingly presents more or less the form of a wedge, with its 
edge obtuse or flattened in the dorsal vertebras, but slightly concave, and with 
its anterior and posterior angles truncated in the caudal vertebrae f. The con- 
tour of the terminal surfaces is nearly circular, with the vertical slightly exceed- 
ing the transverse diameter. The neural arch of the dorsal vertebrae presents 
the complicated exterior, the great height and superior expansion, which cha- 
racterize these vertebrae in other Dinosaurs : the base of each neurapophysis 
equals^ or nearly equals, the antero-posterior extent of the centrum, but im- 
mediately contracts in this direction from the posterior margin, which then 
curves backwards as it inclines towards the opposite neurapophysis, and the 
conjoined laminae are developed beyond the posterior end of the centrum 
to an extent varying in the different regions of the spine. In the dorsal ver- 
tebras the bases of the neurapophyses are developed transversely inwards, so 
as to meet and join each other below the spinal canal : the haemapophyses pre- 
sent an analogous structure through a great part of the tail, the bases of each 
pair, as well as the apices, being united together, and the chevron bones, thus 
formed, are perforated instead of being notched for the passage of the great 
blood-vessels. The neurapophyses are commonly anchylosed to the centrum, 
with a persistent trace of the suture. The transverse processes are straight, 
and of great length in the vertebrae from the middle of the trunk, indicating 
there a considerable expanse of the abdominal cavity, adapted for the lodge- 
ment of the capacious viscera of a herbivorous feeder. The spinous processes 
rise to a considerable height in the dorsal, as well as in the anterior caudal 
vertebrae. The exterior surface of the vertebrae is impressed with fine stri- 
ations, which are mostly longitudinal in the centrum ; so that fragments may 
thus be distinguished from the characteristically smooth and polished vertebrae 
of the 3Iegalosaur%is. The antero-posterior diameter of the largest vertebrae 
of the Iguanodon which I have yet seen is 4^ inches ; the most usual size is 
4 inches. 

Having premised these general characters of the vertebrae of the Iguano- 
don, there next remain to be considered the modifications by which tlaey are 

* The plano-coiicave vertebrse in tlie Mantellian Collection, British Museum, beloug to 
the Cetiosaurus. 

t The large vertebr?e from the Wealden, with obscurely quadrangular or hexagonal bodies, 
which are rather convex or flat on one side and concave on the other, belong to the Ceiio- 
taurus. 



126 REPORT — 1841. 

distinguished in different rogions of the spinal column. Hitherto I have not 
met with any specimen of a cervical vertebra ; the comparatively small frac- 
tured vertebra, Nos. gl^r ^"^ 2%%' " ^^i^ of the Iguanodoti" Mantell. 
Catal., is an ordinary, or more posterior, cervical vertebra of a large Croco- 
dilian Reptile, which, if not belonging to the Poikilopleuron, indicates a spe- 
cies distinguishable from all other known Saurians*. The large cervical ver- 
tebrte with ball-and-socket articular surfaces, agreeing with the Iguanodon 
in size, have been shown to have these surfaces the reverse in position to 
those in the Iguanag and modern Saurians, and to belong to the genus Strep- 
tospondylus. The desirable knowledge, therefore, of the anatomy of that 
region of the spine in the Iguanodon, which in other Saurians is usually 
distinguished by its well-marked and varied characters, remains to be ac- 
quired. 

Costal or dorsal vertebr(B\ . — Towards the middle or anterior part of this re- 
gion tlie bodies of the vertebree are laterally compressed, and meet below at 
an obtuse ridge. Through, apparently, a considerable proportion of the dor- 
sal region of the spine, the neurapophyses rise vertically to a height equal to 
that of the centrum, and expand into a broad and strong platform, the upper 
surface of which is slightly concave transversely, and ai'ched from behind 
downwards and forwards in a regular curve ; this platform is supported by a 
strong vertical buttress on each side, and sends upwards from the whole of 
its middle line a thick, broad and high spinous process. Two oblique, flat, 
articular processes look downwards and outwards from the posterior angles 
of the platform; and the corresponding anterior oblique processes, having 
their flat articular surfaces looking upwards and inwards, and inclining to 
each other at a right angle, terminate the contracted anterior part of the plat- 
form, and do not project beyond it as two distinct processes separated by a 
median fissure. They are not continued beyond the anterior end of the body 
of the vertebrae, and consequently the posterior processes overhang the hinder 

* A portion of this vertebra is alluded to at p. 137, and figured at pi. ix., fig. 1, of Dr. Man- 
tell's Memoir on the Iguanodon, pubhshed in the Philosophical Transactions for the present 
year, 1841, as the " atlas of a young Iguanodon ;" its position iu the neck has been apparently 
determined by the resemblance of the cast of calcareous spar, which fills up the spinal canal, 
to the medulla oblongata. This resemblance arises from the expansion of the open ends of 
the canal ; in which expansions, in the recent Crocodile, the contained spinal chord does not, 
however, in the least degi-ee participate. The longitudinal fissure in the cast is due to a cor- 
responding ridge of bone projecting from the inner surface of the contiguous wall of the spinal 
canal ; doubtless giving attachment to the dura mater of the chord, but not impressing the 
chord itself. The external surface of the vertebra exhibits an upper and a lower transverse 
process for the attachment of a bilobed cervical rib, which unequivocally demonstrates it not 
to agree with the Lacertian type of structure. 

t In the Memoir in the Philosophical Transactions, 1841, above quoted, Dr. Mantell says, 
" The usual characters of the dorsal and caudal vertebra; of the Iguanodon have been pointed 
out in my former works," and refers to the ' Fossils of Tilgate Forest,' and the ' Geology of 
the South-east of England,' p. 136. I have again, therefore, carefully perused the passages 
in which the structure of the vertebrae from the Wealden strata is alluded to in those valu- 
able works, in the hope that the present tedious section of my Report might be cancelled ; 
but they leave the same doubt, which their first perusal occasioned, as to whether the author 
intended to attribute to the vertebra; of the Iguanodon the characters of those of the second 
system of Wealden vertebrae, viz. Cetiosauriis ; or those of the fourth system, viz. Strepto- 
spondylus. See Geology of the South-east of England, p. 306. M. H. v. Meyer adopts the 
former, or the Cetiosaurian ijpe, for his characters of the Iguanodon's vertebrfe, from the 
works to which Dr. Mantell refers. The six caudal vertebrae of the Iguanodon described in 
the Memoir of 1841, are referred to, in the ' Geology of the South-east of England,' at the 
conclusion of the account of the Hylceosaurus, and the accomphshed author there states, " The 
bodies of these vertebraj, like those of the newly-discovered reptile, are shghtly concave at 
both extremities," which is one of the characters whereby they might l)e distinguished from 
the vertebra; of the Cefiosaurus. 



ON BRITISH FOSSIL, REPTILES. 127 

surface of the centrum in order to rest upon the oblique processes of the ver- 
tebra next behind. In the anterior dorsal vertebraa the body supports a large 
and well-marked articular surface on each side, for the head of the rib ; and 
a long and strong transverse process is developed from each neurapophysis 
against the end of which the tubercle of the rib abuts, as in the Crocodile. 
In the hinder costal vertebrje the long transverse process is gradually nar- 
rowed to its extremity, which is abruptly truncated, and has a right-angled 
notch at the anterior part ; the curtailed neck of the rib, no longer expanded 
into a head or joined to the body of the vertebra, is fitted into this notch, 
and the broad and flat surface; at right angles to the neck, is adapted to the 
extremity of the transverse process. 

We seek in vain, in the existing Iguana, for such modes of articulation of 
the ribs as have here been described, while they are common to Crocodiles with 
the Dinosaurs. The fact of the complete inclosure of the spinal canal by 
the meeting and confluence of the bases of the neurapophyses beneath it, 
was first brought to my attention by the appearances in the body of a dorsal 
vertebra of the great Horsham Iguanodon, in the collection of Mr. Holmes. 
This centrum, which measures 4|- inches in length and 5 inches across its 
articular extremity, presented only a slight trace of the impression of the 
spinal canal at the anterior part of its upper surface, the rest being occujjied 
by a slightly concave, continuous, rough articular surface. The deficiency 
of this vertebra was supplied by a fine specimen in Mr. SauU's collection of 
the separate neural arch of a dorsalVertebra of a corresponding size, which 
seemed to have been detached from a natural articulation. I saw with much 
interest that the bases of the neurapophyses met and joined each other below 
the spinal canal along the posterior half of their longitudinal extent, present- 
ing at their under part a continuous slightly convex surface, which must have 
left a corresponding concave rough articular surface upon the upper part of 
the centrum, like that exhibited by the Horsham vertebral body. The base 
of each neui'apophysis, which is longer than it is wide, describes a slight 
curve, convex in the antero-posterior direction, downwards or towards the 
centrum. The spinal canal is nearly cylindrical, very slightly expanded at the 
two extremities ; its diameter 1 inch 5 fines. The chief buttress of the spinal 
platform rises from the posterior and outer part of the base of the neurapo- 
physis, and ascends almost vertically, slightly inclining forwards ; it is com- 
pressed, with its plane transverse to the axis of the vertebra ; it expands as 
it blends with the under part of the broad platform, half-way between the 
anterior and posterior boundaries of that remarkable part of the neurapophy- 
sis. A second buttress rises from the anterior part of the base of the neura- 
pophysis, and ascends vertically to the upper and outer end of the anterior 
oblique processes. The base of the transverse process is situated above the 
converging point of the two buttresses. In the interspace of the two but- 
tresses of the anterior dorsal vertebrae there is a large oval articular surface, 
convex at the anterior and concave at the posterior part, which has aff'orded a 
lodgement to the head of an enormous rib. The oblique or articular processes, 
directed as described in the general observations on the vertebra of the Igua- 
nodon, converge and meet at nearly a right angle. There is a wide depression 
at the posterior broad part of the base of the spine, and a wide and deep fossa 
between the posterior buttress and the posterior oblique process. The base of 
tlie spine, as it extends forwards along the middle of the broad platform, de- 
scends with a graceful curve to the interspace of the anterior oblique pro- 
cesses. The platform recedes on each side from the base of the broad spine 
with a regular concavity to its plane ; its surface is coarsely striated trans- 
versely. 



128 REPORT— 1841. 

The following are dimensions of this interesting fossil : — 

In. Lin. 

Length of the base of the neurapophysis* 4 6 

From the base of the neurapophysis to the middle of the base \ ? ^ 

of spinous process j 

From the base of the neurapophysis to the posterior part of 1 en 

the base of spinous process j 

From the base of the neurapophysis to the anterior part of I q c 

the base of spinous process J 

Antero-posterior extent of base of spinous process 6 6 

Transverse diameter of spinal platform 8 6 

Transverse diameter of conjoined bases of neurapophysesf ..40 
Extent of spinal platform beyond hind part of base of neura- 1 4, ^ 

pophysis J 

The spinous process is broken off near its base in this specimen, which is 
otherwise remarkably entire, considering that it was washed out of the sub- 
merged beds of the Wealden and cast on the south shore of the Isle of Wight. 
It was found near Culver Cliff. 

The characters thus obtained from two different parts of the vertebrae of 
two Iguanodons from distant localities, certified to belong to that genus from 
the association of one of the parts, viz. the vertebral centrum, with many other 
characteristic bones of that reptile, have their value increased from the cir- 
cumstance of the obscure and unsatisfactory manner in which the vertebral 
characters are exhibited in the celebrated specimen from the Maidstone 
quarry. The eight vertebrae originally forming a continuous series in this 
specimen are from about the middle of the back ; the antero-posterior dia- 
meter of each is 3^ inches. Little more can be determined from these or from 
the detached and crushed dorsal vertebrae in this specimen, except the flatten- 
ing of the sides of the vertebrae and their convergence to the lower surface, 
the slight concavity of both articular extremities, the height of the neural 
arch, and the strength and length of the transverse and spinous processes. 

With the evidence afforded by the previously described specimens, the cha- 
racters afforded by the following detached vertebrae from the Tilgate strata may 
with confidence be applied to the further elucidation of the osteology of the 
Iguanodon. 

An anterior dorsal vertebra (No. ^, Mantellian Collection), having the 

following dimensions of the centrum, — 

In. Lin. 

Antero-posterior diameter 3 11 

Vertical diameter of articular end 4 1 

Transverse diameter of articular end 3 2 

measures, from its under surface to the posterior part of the base of the 
spinous process, 8 inches. The broad and high neural arch is anchylosed 
with the centrum, but the nearly straight line of suture is indicated by nume- 
rous puckered rugae and striae. The transverse process extends from the side 
of the neurapophysis ; its base is vertically oval, measuring 21 inches by 2 
inches. The neurapophysis expands above this surface into a broad plat- 
form, with a thick i-ough external free border, probably fi'actured. The plat- 
form is supported by a buttress-like ridge, rising vertically from the posterior 
angle of the base of the neurapophysis, and expanding as it ascends to blend 
with the under part of the overhanging platform. Behind this buttress-is a 

* This doubtless gives the length of the centrum to which it was attached, 
t At their anterior and broader part. 



ON BRITISH FOSSIL REPTILES. 129 

wide and deep depression, and the neurapophysis extends backwards to form 
the posterior articular processes which project 1^ inch beyond the hind sur- 
face of the centrum. The antero-posterior extent of the neurapophysial plat- 
form is 6 inches ; the dimensions of the oval articular surfaces of the oblique 
processes are 2 inches by 2^ inches ; the inferior margins of the posterior 
processes are separated by a groove. A smaller anterior ridge extends along 
the anterior part of the neurapophysis. The base of the spinous process ex- 
tends from the posterior triangular interspace of the oblique processes forwards 
and downwards along the curve of the supporting platform ; the thickness of 
the spine, which is 1 inch at the posterior part of the base, gradually dimi- 
nishes towards the fore part of the vertebra. The anterior oblique processes 
form the sides of an angular depression in front of the base of the spine. 

The spinal platform of the Iguanodon differs from that of the Megalosau- 
rus in its greater relative antero-posterior extent, arising from its being ex- 
tended further back ; the platform is also raised higher above the centrum. 

No. ^. Mantellian Collection, is a dorsal vertebra, posterior in situation 
to the preceding, and from an individual of the same size. The neural arch 
is anchylosed, but the sutural line is obvious. The surface for the head of the 
rib on the side of the neurapophysis is smaller, and a transverse process begins 
to be developed above that surface, throwing its aspect somewhat downwards. 
The costal surface is separated in this as in the preceding vertebra by a strong 
vertical ridge or buttress from the wide depression below the posterior part 
of the base of the spine. The angle between the oblique processes is rather 
more open. The spinous process of this vertebra, almost entire, is detached 
from the neural platform, but is cemented to the same mass of stone: it is 
9 inches in height and 3 in breadth, or antero-posterior extent; the summit 
is, however, wanting. The following are other dimensions of the present ver- 
tebra :— ■ In. Lines. 

Antero-posterior extent of the body 3 10 

Vertical diameter of the body 3 9 - 

Transverse diameter of the body 3 7 

The sides of the centrum are as usual concave lengthwise, but are slightly 
convex vertically, and converge to the lower surface, which is formed by an 
obtuse ridge. 

In a dorsal vertebra of the Horsham Iguanodon in Mr. Holmes's collection, 
from apparently the middle of the back, the spinous process, which is 8 inches 
in length, expands gradually in breadth and thickness as it ascends to its trun- 
cated summit, the antero-posterior diameter of which is 4 inches, its trans- 
verse diameter or thickness being 1 inch 6 lines. 

In a series of eight posterior dorsal vertebrae, measuring together 1 foot, 
and consequently from a young Iguanodon in Mr. Holmes's collection, the 
spinous process of the most anterior one is, in antero-posterior diameter, 7 
lines, but increases in the other vertebrae to 15 lines, which shows a somewhat 
rapid change of character. 

Sacral Vertebrce. — The highly remarkable and characteristic structure of 
the sacrum of the Megalosaurus, and the strong indications of close affinity 
between this gigantic carnivorous reptile and the still more colossal herbivo- 
rous Igxianodon, wliich the structure of their costal vertebrae, of their ribs, 
and of the larger bones of their extremities afford, made it very desirable to 
ascertain whether the Iguanodon deviated in the same manner from other 
Saurians, existing and extinct, in the extent and structure of the sacral region 
of the spine. 

The collection of the remains of the Iguanodon in the British Museum does 
1841. K 



130 REPORT— 1841. 

not include this characteristic part of the skeleton ; it does not form part of 
the series of bones obtained by Mr. Holmes from the Wealden Quarry at 
Horsham ; but in the collection of rolled bones of the great Wealden Sau- 
rians — Cetiosaurus, Streptospondylus, and Iguanodon — in the museum of 
Mr. SauU, there is a fine specimen of the sacrum with one of the iliac bones 
attached, which, in the proportions of the vertebrae and the form of the ilium, 
agrees with the known characters of the Iguanodon. 

This instructive specimen consists of five vertebrae anchylosed together by 
the articular surfaces of their bodies and by their spinous processes, which 
seem to fonn a continuous thick median ridge of bone. The five vertebrae 
measure 17 inches in length. The articular extremity of the terminal sacral 
vertebra is very slightly concave and subcircular, measuring 3 inches in both 
vertical and transverse diameter. The bodies of the dorsal vertebrae are com- 
pressed at their middle part, and broader below than in the dorsal region, and 
concave in the direction of their axis, the concavities being separated by the 
broad prominent convex transverse ridges formed by the anchylosed and os- 
sified intervertebral spaces. The contour of the under part of the sacrum 
thus forms an undulating line. The lateral and inferior surfaces are separated 
by a more angular prominence of the centrum, the under surface is less con- 
vex transversely, and the whole centrum is shorter in proportion to its depth 
and breadth, than in the Megalosaurus. The neurapophyses present the same 
remarkable modification in regard to their relations to the body of the ver- 
tebra as in the Megalosaurus, having shifted their position from the upper 
surface of a single centrum to the interspace of two, resting on proportions 
of these, which are more nearly equal, as the vertebrae are nearer the middle 
of the sacrum. The nerves were compelled therefore to escape from the 
spinal canal over the body of the vertebra, more or less near its middle, and 
they impress the upper surface there with a smooth canal. 

The strong, vertically compressed, transverse processes, or sacral ribs, rise 
from the bases of the neurapophyses, and their origin extends upwards upon 
the Ispine, and downwards upon the sides of the contiguous vertebral bodies 
and intervertebral space; in the specimen described they are firmly anchy- 
losed to all these parts, extend outwards and expand at their extremities, four 
of which meet, join, and form an elongated tract of varying breadth to which 
the ilium is firmly attached. The length of the largest penultimate transverse 
process was 5 inches 8 lines, its vertical breadth at the middle 3 inches, its 
thickness here 1 inch. The adjoining (last) transverse process was 5 inches 
in length ; the interspaces of the transverse processes equalled from 2\ inches 
to 2 inches. The sacrum increases in breadth posteriorly ; its transverse dia- 
meter, including the anchylosed ilia taken at the posterior part of the ace- 
tabulum, is 13 inches, at the anterior part of the sacrum only 8 inches. The 
proportion of the spine thus grasped, as it were, by the iliac bones, which 
transmit the weight of the body upon the thigh-bones, corresponds with the 
mass which is to be sustained and moved ; and the size and structure of the 
sacrum indicate, with those of the femur and tibia, the adaptation of the 
present great herbivorous Saurian for terrestrial life. 

No. ^, Mantellian Collection, is the centrum of a sacral vertebra of a sub- 
quadrate form, with a broad and flattened inferior surface, slightly concave 
antero-posteriorly. The upper surface is excavated by a wide and moderately 
deep canal, indicating the unusual size, for Reptiles, of the sacral portion of 
the spinal chord. The anterior and posterior parts of the sides of this cen- 
trum are raised, so as to form projecting sub-triangular rough articular sur- 
faces, continued upon the margins of the spinal canal, evidently for the at- 
tachment of the neurapophyses and the heads of the strong sacral ribs. The 



ON BRITISH FOSSIL REPTILES. 131 

interspace of these anterior and posterior neurapophysial surfaces is formed 
by a smooth oblique groove, connecting the smooth surface of the spinal canal 
with that of the free lateral surface of the vertebra, and indicating the place 
of exit of the sacral nerves, which is necessarily in this unusual situation, be- 
cause the ordinary holes of conjugation must have been obliterated by the 
impaction of the bases of the neurapophyses between the contiguous extre- 
mities of the bodies of the sacral vertebrae. 

The anterior and posterior articular extremities of the present interesting 
fossil equally bespeak the peculiar character of the sacral vertebrae of the 
Dinosauria. They are impressed by coarse straight ridges and grooves ra- 
diating from near the upper part of the surface, like those on the correspond- 
ing part of a cetaceous vertebra when the epiphysial articular extremity is 
removed. These inequalities are here, doubtless, preparatory to that anchy- 
losis by which the sacral vertebrae are compacted together in the mature Di- 
nosaurs. 

In. Lines. 

The length of this vertebra 2 10 

The height 2 6 

The breadth of anterior articular end , 3 

The breadth of middle 2 2 

Antero-posterior diameter of anterior costal surface . 1 7 
Antero-posterior diameter of posterior one .... 1 

Breadth of spinal canal 1 5 

Breadth of canal of sacral nerve 4 

From its separated condition, the body of the sacral vertebra here described 
must have belonged to a young Dinosaur of a size far exceeding that of the 
HylcBOsaurus. It is obviously very distinct in form from the sacral vertebrae 
of the Megalosaurus. No other reptile than one belonging to the order cha- 
racterized by the peculiar structure of the sacrum already described, could 
have yielded a detached vertebral centrum with the remarkable modifications 
of the one under consideration. The modifications detected in the entire 
sacrum of the Iguanodon in Mr. SauH's collection, justify the reference of the 
vertebra above described to the sacrum of a young Iguanodon. 

Caudal Vertebrce. — These are distinguished by the single haemapophysial 
surface at each end of the narrow inferior surface of the centrum. The sides 
of the centrum are flat, or even slightly concave in the vertical direction, 
though less so than in the antero-posterior direction. In a caudal cen- 
trum, for example, in the Mantellian Collection, measuring ^ inches in 
length, and 5 inches 4 lines in depth at the middle of the side, if a pencil 
be laid vertically along that part, an interval of between 1 and 2 lines sepa- 
rates its middle part from the bone. Those great Wealden vertebrae which, 
on the contrary, have the middle of the side of the body prominent, and the 
lower half only converging towards the under surface, are from the middle 
and posterior part of the tail of the Cetiosaurus. The posterior terminal ar- 
ticular surface is rather more concave than in the dorsal vertebrge ; but the 
difference is by no means so marked as in the plano-concave vertebrae of the 
Cetiosaurus. The transverse processes of the anterior caudal vertebrse are 
comparatively short, but strong, and are continued from the base of the neur- 
apophysis. 

The haemapophyses, or chevron bones, are not anchylosed to the centrum, 
but articulate with the interspaces of the vertebrae ; in a few of the anterior 
ones to two distinct but closely approximated surfaces on each contiguous 
vertebra, but in the rest of the caudal vertebrae to a single oblique triangular 
surface on each of the contiguous extremities of the centrum; the haemapo- 

k2 



132 REPORT — 1841. 

physes being here confluent at their vertebral as m ell as at their distal ex- 
tremities. 

A caudal vertebra exhibiting this modification in Mr. Holmes's collection 
measures, in the vertical diameter of the articular surface, •i inches 9 lines ; 
in its transverse diameter, 4 inches 6 lines ; the breadth of the inferior sur- 
face of the vertebra is 3 inches 3 lines. The interspace between the anterior 
and posterior haemapophysial surface is 9 lines ; it is concave in the axis of 
the vertebra. The diameter of the spinal canal is reduced in this vertebra to 
9 lines. The transverse processes are of very small size. The spinous pro- 
cess is broken off. We have seen that those of the sacral vertebrae appear to 
have been short. There is reason to think that the spinous processes increased 
in length for a certain distance as they receded from the sacrum, and then dimi- 
nished. Thus, in a caudal vertebra (No. 2^, Mautellian Collection), evidently 
anterior in position by its size, by its oblique processes, and by the place of 
development of its transverse processes from the base of the neural arch, 
the spinous process is 5 inches in height, while in the six caudal vertebrae 
preserved in natural sequence and relative position in the Mantellian Collec- 
tion, the spines are more than double that height. That the vertebra (No. 
2130) is not a more posterior caudal vertebra from a larger Iguanodon is 
shown by the relative thickness, as well as position, of its transverse pro- 
cesses, as compared with the six caudal vertebras above mentioned, for their 
transverse processes sensibly diminish in every diameter, and especially in 
vertical thickness, from the first to the sixth ; and, moreover, it is evident 
that, in this short series, the spines decrease in height both forwards from the 
third as well as backwards, but more so in the latter direction. Thus the 
spine of the first of these vertebrae is M inches high, of the third 15 inches, 
and of the sixth 13 inches. These spines increase in breadth toward their 
summits, which are truncated, and in contact with each other, partly from 
this expansion, partly from the posterior ones being slightly bent forwards. 
One cannot witness this change of character in so short a segment of the tail 
without a conviction that this appendage must have been relatively shorter 
than in the Iguana. 

The first spine, besides being somewhat shorter, is more rounded off at its 
anterior margin than the third, a difference which is still more obvious in the 
detached caudal above described ; but above its origin a thin trenchant plate 
is extended for a short distance from the middle of the anterior margin : this 
character, which calls to mind one that is present in a greater proportion of 
the vertebral column in the Crocodilians, is more strongly developed in the 
second and third vertebree. The neurapophysial suture is more nearly ob- 
literated in the sixth than in the first of this instructive series, or in the more 
anterior and detached caudal vertebra. The following are dimensions of the 
detached anterior caudal (No. 1), and of the first (No. 2) and last (No. 3) 
of the series of six : — 

Antero-posterior diameter of centrum , . . 
Vertical diameter of articular surface . . . 
Transverse diameter of articular surface . . 
From under part of centrum to upper end 1 r £• 

of posterior articular process . . . . j 5 8 4 

From upper end of posterior oblique pro- 1 

cess to the summit of spine . . . . J '^ " 14 10 6 
Antero-posterior diameter of base of spine .13* 17 14 
Antero-posterior diameter of summit of spine 2 2 2 2 6 
* The anterior basal ridge of this vertebra is broken away. 



No. 1. 


No. 2. 


No. 3. 


In. Lin. 


In. Lin. 


In. Lin, 


2 8 


2 8 


2 7 


3 6 


3 3 


2 6 


3 5 


3 2 


2 6 



ON BRITISH FOSSIL REPTILES. 133 

The transverse processes disappear in the posterior caudal vertebras. The 
chevron bones, of which three are preserved in the slab containing the six 
caudal vertebree, exhibit the perforated character which distinguishes them 
from those of the Cetiosaurus and of all existing Crocodiles and Lizards, not 
excepting the Iguana, in which the haemapophyses are anchylosed at their 
distal or spinal end only, and remain separate and articulated to two distinct 
surfaces, at their proximal ends. The length of the superior and inferior 
vertebral spines, and the shortness of the transverse processes, prove the form 
of the tail to have been flattened laterally and of great breadth in the vertical 
direction, at its basal portion at least. 

Ribs. — These appendages of the vertebral column are largely developed in 
the thoracic abdominal region of the spine, and had the same two-fold con- 
nexion with the vertebrae as in the other Dinosaurs and the Crocodilians. At 
the anterior part of the costal region of the spine, the rib was joined by a 
large head to a shallow cavity, situated at first on the side of the centrum and 
then on the side of the neurapophysis ; and it was further articulated by a 
tubercle to the extremity of the transverse process. In a certain number of 
the anterior vertebrae, the neck of the rib was co-extensive with the transverse 
process, and sometimes six or seven inches in length ; afterwards the neck of 
the rib began to shorten, and the head to decrease in size, and to have its place 
of articulation brought progressively nearer to the end of the transverse pro- 
cess, until it finally disappeared, and the posterior ribs became appended to 
the ends of the transverse processes. 

In the Iguana, as in other Lizards, the ribs have but one mode of articu- 
lation, viz. to a simple tubercle developed from the side of the centrum. 

One of the largest double-jointed ribs of the Jguanodon, in the Mantellian 
Collection (No. gjig)' is 46 inches in length. The neck is less distinct from 
the tubercle and body than in other ribs, which seem to have been situated 
further back ; it expands more gradually to the tubercular articulation with 
the transverse process, and is at this part 5 inches in breadth ; it bends with 
a deep oblique curve for about one-fifth of its length, and then is continued 
in a nearly straight line to its extremity : this is slightly expanded and trun- 
cated, for the attachment doubtless of a bony sternal rib. The convex or 
outer margin of the rib is bent backwards so as to overhang the sub-com- 
pressed shaft of the bone along its upper or proximal third part. 

The proximal extremity of one of the ribs from the middle of the trunk of 
the Horsham Iguanodon, presents an ovate head 2^ inches in the long dia- 
meter ; the neck is 7 inches long, straight, compressed, and topped by a well- 
marked tubercle, where it joins the body of the rib. This part is also com- 
pressed ; and its external margin, besides being bent backwards, is also deve- 
loped in the contrary direction, so as to assume the form of a slightly convex 
plate of bone 2 inches broad, attached at right angles to the shaft of the rib, 
which it overhangs on both sides. This structure is characteristic also of 
some of the ribs in the other Dinosaurs, and is interesting as indicating the 
commencement of that peculiar development of the corresponding part of the 
ribs in the Chelonian reptiles, by which the upper part of their bony box is 
almost wholly formed. 

Bones of the Extremities. 

Scapular Arch. — The scapula has not hitherto been discovered so asso- 
ciated with other unequivocal portions of the skeleton of the Iguanodon as to 
permit the characters of this bone in that species to be confidently recognised. 
The bone (No. 194', Oniopliitc of Iguanodon, Mantell. Catal.) agrees with 



134 REPORT — 1S41. 

the undoubted scapula of the Hylaeosaur, and with that of certain Lacertians, 
especially of the genus Sciticus*, in the production of a long and slender 
pointed process, continued at nearly right angles with the body of the bone, 
from the anterior part of the articular surface for the coracoid ; but it differs 
from the scapula of the Hylasosaur in the presence of two short processes 
given off from the lower part of the base of the long process, and in the ab- 
sence of the thick and strong transverse acromial ridge which overarches the 
glenoid depression, and in the deeper concavity of the posterior margin of 
the ascending plate or body of the bone, 'i'his part, in its shape, relative 
length and breadth, is intermediate between the Crocodilian and Lacertian 
type of the scapula, at least as exemplified in the Monitors and Iguanas, where 
it is broad and short. The Seines and Chameleons, in the more Crocodilian 
proportions of their scapulae, resemble the Hylaeosaur and the great species 
of extinct Saurian, most probably the Iguanodon, to which the present bone 
belongs. 

Coracoid. — The thick articular portion of this bone, with its characteristic 
perforation, here continued to the articular margin by a narrow fissure, di- 
viding the scapular from the humeral articulation, ha^ been found of different 
sizes in the Tilgate strata, and has been, with much probability, likewise re- 
ferred to the Iguanodiiii. One of these portions of coracoid, which measured 
10 inches in diameter, was found in the same block of stone with other 
unequivocal remains of Iguanodon. 

Clavicle. — The doubts which are attached to the determination of the pre- 
vious parts of the scapular arch are fortunately dissipated from the considera- 
tion of this bone by the preservation of both the right and left clavicles in 
the Maidstone Iguanodon. The presence of the fibula in the same block of 
stone, and its discovery in close proximity with the tibia and femur in the 
Wealden strata, satisfactorily prove that the present remarkable bone cannot 
have formed part of the hinder extremity. And since, in other reptiles, the 
radius differs from the fibula in little more than in being somewhat shorter 
and thicker, there is still less reason for supposing it to belong to the fore-arm. 

The form of the ribs of the Iguanodon is well known, and they become 
shorter and more curved as they advance from the middle to the anterior part 
of the chest. The determination, therefore, which Dr. Mantell regarded as 
most probable t, must be held to be the true one. The largest entire clavicle 
from the Wealden strata measures 29 inches in length, and there is a portion 
of another in the same collection one-third larger. The largest fibula of the 
Iguanodon that has been found measures 28 inches. The bone is compressed, 
slender, and subtrihedral at the middle part, expanded and flattened at the two 
extremities, bent with a slight double curve in a graceful sigmoid form. The 
broadest end, which, from the analogy of the Cyclodus lizard, must be re- 
garded as the median or pectoral extremity, gives off two processes, the first 
appearing as a continuation of the thinner margin of the bone, twisted and 
produced obliquely downwards ; the second process is given off nearer the 
expanded sternal end, towards which it slightly curves. 

* Dr. Mantell has pointed out this resemblance in his Memoir in the Phil. Trans., 1841. 

t " If we consider the form of this hone, it appears that the only place it can hold in the 
skeleton must be either the thorax or lower extremities ; it may be a iibula, a rib, or a cla- 
vicle; and that it is a clavdcle of some extraordinary extinct reptile is certainly most pro- 
bable." — Geology of the South-east of England, p. 309. The subsequent discovery of the 
Maidstone Iguanodon determined the species of reptile to which the bone in question be- 
longed, and the comparisons mentioned in the text prove it to be a clavicle. The bone 
attacl»ed to the coracoid and oraoplate of a small lizard, which I pointed out to Dr. Mantell 
as resembling the one in question, was the clavicle of the Cyclodus nigroluteus. See Dr. 
Mantell's late Memoir of 1?41, Phil. Trans., p. 138. 



ON BRITISH FOSSIL REPTILES. 135 

In. Lin. 

The breadth of the expanded sternal end of'a clavicle, 29 1 „ ,. 

inches in length, is J 

The breadth of the scapular end 4 3 

From this extremity to the base of the first process . . .19 
The breadth of the narrowest part of the shaft .... 1 7 

Humerus. — This important bone has not been hitherto satisfactorily deter- 
mined ; it differs less from the femur in form in Reptiles than in Mammalia. 
In the Crocodilians it is shorter than the femur, especially in the extinct pis- 
civorous species, with biconcave vertebrae and more strictly aquatic habits. 
In Lizards it is more nearly equal with the femur, and the similarity of the 
size of these bones we may conceive to have been greater in the gigantic ter- 
restrial Dinosaurs. 

In the modern Crocodiles, the chief distinction in the form of the humerus 
is the ridge at the upper third of the bone : in Lizards this distinction is 
almost lost. If we find the femur of the Iguanodon distinguished from that 
of all other reptiles by the presence of a peculiar process from the inner side 
of the bone, there are not wanting grounds to expect that the humerus may 
present a similar character. 

As the reasons for suspecting that some of the large bones, hitherto uni- 
formly regarded as the femora, may be the humeri of the Iguanodon, will best 
appear in the description of the femur, I shall now proceed to the considera- 
tion of the large bones with which the femur is articulated. 

Ilium.— The iliac bone o{ the IgjMnodo7i* resembles in form that of the Mo- 
nitor more than that of the Iguana : in the portion of the pelvis in Mr. SauU's 
collection it measured 14 inches in length. It commences anteriorly by a 
thick obtuse extremity slightly bent outwards ; this part is supported by the 
thickest and strongest of the sacral ribs, which slightly inclines backwards : 
the ilium quickly increases in vertical as well as transverse extent, forming at 
its lower part the usual portion of the acetabulum ; the concavity terminating 
behind in a broad obtuse prominence : behind this part the ilium rapidly con- 
tracts, by a deep inferior emargination, to a comparatively slender process ex- 
tending backwards and gradually diminishing to an obtuse point, well shown 
in the detached ilia of the Maidstone Iguanodon, but here broken off. The 
chord of the acetabular arc or concavity, in Mr. SauU's specimen, measured 
8 inches. 

In the Maidstone Iguanodon the left ilium lies detached, with its sym- 
physial articulation or inner surface uppermost, indicating by the extent of 
that surface, which equals the antero-posterior diameter of nearly five of the 
dorsal vertebraj of the same individual, the length of the sacrum peculiar to 
this and other Dinosaurian reptiles. Its slender posterior portion terminates 
in a subacute point : the anterior extremity of the right ischium, which has 
the opposite surface exposed, bends slightly outwards in the form of a thick 
tuberosity. In. Lin. 

The length of this bone is 16 

Its depth 5 

From the anterior tuberosity to the posterior angle 1 g q 
of the acetabulum J 

Pubis This bone, which presents a simple spatulate form in the Croco- 
diles, already begins to increase in breadth at its symphysial extremity in the 
extinct family with concave vertebra ; and in the larger existing species of 
Lizards is expanded at both extremities, and has a very marked and recog- 

* This bone is figured in Dr. ManteU's Memoir, Phil. Trans. 1841, pi. viii. fig. 28. 



136 REPORT — 1841. 

nizable character superadded, in being bent outwards with a considerable 
curvature. 

A massive fragment of a broad osseous plate, bearing a segment of a large 
articular cavity at its thickest margin, and thence extended as a thinner plate, 
bent with a bold curvature, and terminated by a thick rounded labrum, offers 
characters of the Lacertian type of the pubis too obvious to be mistaken. 
This specimen is from .the Tilgate strata; and, since the modifications of the 
ilium of the Iguanodon in the Maidstone skeleton approximate to the Lacer- 
tian type of the bone, and especially as manifested by the great Varani, in 
which the recurved character of the pubic plate is most strongly marked, we 
may, with much probability, assign the fossil in question to the pelvis of the 
Iguanodon. 

This fine portion of pubis is of an inequilateral triangular form, 16 inches 
in its longest diameter, 9 inches 6 lines across its base or broadest part, 

6 inches 8 lines across its narrowest part. The fractured surface of the bone, 
near the acetabulum, is 3 inches 3 lines thick. The acetabular depression is 

7 inches across, a proportion which corresponds with that of the acetabular 
concavity in the ilium, and with the size of the cavity in which the head of 
the Iguanodon's femur must have been received. One, angle of the cavity, 
corresponding with the anterior one in the Varanus, is raised ; a broad and 
low obtuse ridge bounds the rest of the free margin of the cavity. The 
smooth labrum exchanges its character near one of the fractured edges of 
the bone for a rough surface, which indicates the commencement of the sym- 
physis. In the apparent absence of the perforation below the acetabular de- 
pression, the present bone agrees with the Crocodilian type. 

Ischium — A second fragment of a large lamelliform bone (No. ^g, Man- 
tellian Catalogue) presents, in its general form and slightly twisted character, 
most resemblance to the ischium, with traceable modifications intermediate 
to those presented by the extinct Goniopholis and modern Varani and Iguance, 
The loss of the acetabular extremity, which is broken away, prevents a cer- 
tain determination of this bone ; the only natural dimension that can be taken 
is the circumference of the neck, or contracted portion between the acetabu- 
lar end and the expanded symphysial plate : this circumference gives 7 inches. 
The slight twist of the bone upon this part as it expands to form the broad 
symphysial plate, — a character which is well marked in the ischium of the 
Goniopholis, — gives it a superficial resemblance to the humerus of some of the 
large Mammalia ; but the bone is too short in proportion to the breadth in- 
dicated by the fractured symphysial end, to afford a probability of its having 
been the humerus of a land reptile, and much less of the Iguanodon, in which 
the form of the femur is well ascertained ; unless, indeed, there be actually 
more discrepancy between the femur and humerus in size and form in the 
Dinosaurs, than has, hitherto, been recognized in the Reptilian Class. 

Femur.-^The Maidstone Iguanodon does not satisfactorily determine the 
question of the principal bone of the fore and hind extremities, for whilst the 
clavicles, many anterior dorsal vertebrse and anterior ribs, would lead one to 
suppose that the two long bones found in their proximity might be humeri ; 
on the other hand the presence of the iliac bones, with some caudal vertebrae 
in the same slab, give equal probability to their being femora. The bones in 
question (1 and 2 in the figure of the Maidstone Iguanodon, published by Dr. 
Mantell in his ' Wonders of Geology,' vol.i. pi. ii.) have the same general cha- 
racters, viz. the fiattened trochanter at the proximal end, the compressed ridge- 
like process at the middle, and the two condyles with the deep and narrow 
fissure at the distal end, which are presented by the larger detached bones, 
described by Dr. Mantell as femora, from the Tilgate strata. They are other- 



ON BRITISH FOSSIL REPTILES. 137 

wise too much crushed and buried to yield materials for more minute com- 
parison : each of these bones measures 33 inches in length. 

In five separate long bones, having the general characters of the two above- 
mentioned in the Maidstone Iguanodon, numbered consecutively and marked 
* Femur' in the Mantellian Collection, Nos. 1 and 3 differ from Nos. 4 and 5 in 
the greater inward production of the head, making the concavity of the line 
descending from the head to the median internal ridge somewhat deeper. The 
lower angle of this median ridge is more produced in Nos. 1, 2 and 3, than in 
Nos. 4 and 5. The whole inner contour is more regularly concave in No. 5, 
than in Nos. 1 or 3. Of these five bones, No. 2 was found associated with a 
tibia and fibula ; and if, therefore, the differences above indicated should be 
more than mere individual varieties of the same bone, we might conclude 
Nos. 4 and 5 to be humeri. Such conclusion appears more probable from the 
circumstance of two of the longest and largest of the bones, having the gene- 
ral characters of the femur of the Iguanodon, which were obtained by Mr. 
Holmes from the quarry of the Wealden stone at Horsham, belonging both to 
the right side. 

Now the other bones obtained in proximity with the above were all parts 
of one large individual, and it is much more probable, therefore, that we have 
here a right humerus and femur of the same individual, than two right femora 
of different individuals. One of the differences noticed in the Tilgate speci- 
mens, viz. the degree of obliquity at which the neck joins the shaft, is dis- 
cernible in these ; and close to that bone, which shows the characters that we 
have supposed to belong to the femur, were found bones corresponding with 
the tibia and fibula. 

Regarding then this as the femur, it presents the following characters : — it 
measures 3 feet in length : its circumference at the middle of the shaft is 18 
inches: the contour of the rounded inward-projecting part of head is 17^ 
inches : two flat longitudinal facets meet near the middle of the anterior sur- 
face of the shaft at a rough and slightly elevated angle, which runs straight 
down to within thirteen inches of the distal end : the ridge there inclines to- 
wards the internal condyle and subsides. Two strong vasti intermts et ex- 
ternus muscles are indicated by this ridge. The head of the bone is carried 
inwards, overhanging the shaft in a greater degree than the corresponding 
part does in the humerus. The line of the inner side of the shaft describes 
a graceful sinuous curve, being first concave, then slightly convex at the 
middle, where there is an indication of the projecting ridge which has been 
broken off: below this it is concave to the flattened antero-posteriorly ex- 
tended, slightly concave surface, which descends vertically to the articular 
surface of the condyle, which surface proceeds horizontally at nearly a right 
angle with the line of the shaft of the bone. The antero-posterior extent of 
the flattened condyle is 8 inches. The thickness of the external wall of the 
shaft varies from half an inch to an inch. 

Both ends of this fine bone are crushed and mutilated. 

By the side of the femur were found two other bones, the largest of which 
corresponds with the tibia. The external part of the head is considerably pro- 
duced horizontally; the circumference of the proximal articular surface is 30 
inches. The longitudinally finely striated vertical surface of the shaft of the 
bone commences at the anterior part of the proximal end along a well-defined 
curved line, which runs transversely across the bone, convex downwards in 
the middle and concave downwards at each end : the bone rapidly contracts, 
and assumes, about 8 inches below the head, the subquadrilateral form ; it is 
broadest from side to side: its circumference is here 15 inches. The anterior 
surface is flattened ; the outer or radial side convex or rounded : the dense ex- 



138 REPORT — 1841. 

ternal walls of this bone are very thick, at least 1 inch. The length of this 
bone is 27 inches, but. it wants the distal end. The proximal articulation is 
very convex from behind forwards, but, at the middle, it is slightly concave 
from side to side. In. Lines. 

Its lateral diameter is 12 

Its antero-posterior diameter is 5 6 

The disparity of size between the tibia and fibula is considerable, but the 
disparity in the thickness of the two extremities of the bone is less than in the 
bone which is described and figured as the fibula by Dr. Mantell. On the 
middle of one of the flat sides of the fibula is an oblong rough surface slightly 
raised, measuring 3 inches by 2 inches. The articular extremities of the fibula 
are tuberculate ; the larger end is 4 inches across, the smaller one 3 inches 
across. The shaft is subcompressed. 

A few yards from the three preceding bones was found the, presumed, hu- 
merus, which measured 35 inches in length, being very nearly equal in size 
with the femur. Its proximal extremity is crushed and mutilated : the shaft 
is compressed from before backwards ; concave behind : the submedian ridge 
or compressed process is developed from the inner side of the shaft at the usual 
situation, and corresponds in form with those of the bones Nos. 4 and 5, Man- 
tellian Collection. The distal condyles are divided anteriorly by a narrow lon- 
gitudinal furrow, which penetrates deeply between them. As the absence of the 
deep fissure between the condyles of the femur is repeated in the humerus of 
the Iguana, so may its presence be repeated in the humerus of the Iguanodon. 

The inner condyle projects backwards beyond the outer one, which is di- 
stinguished by being traversed by a longitudinal groove. This bone difliers 
from the femur in the shorter neck supporting the head, in its more promi- 
nent median process, and in the uniform though slight concavity of the inner 
margin of the shaft. 

The preceding observations were made during an inspection of the fossils 
in Mr. Holmes's interesting collection in the summer of 1840. I have subse- 
quently been favoured by a letter from that gentleman, containing the follow- 
ing clear and valuable observations on tiie two large bones in his collection, 
which support the view I had taken of their nature. 

"I have also examined the two large bones concerning which so much 
doubt exists. They both appear to belong to right extremities, but as the 
one which has the trochanter, and which by way of distinction I shall call 
No. 1 (humerus?), is so much crushed in the direction of the rough ridge, so 
strongly marked in the other, I cannot say with any degree of certainty whe- 
ther it possessed the same form or not. There is, however, this difference at 
any rate. The head of No. 1 is so much mutilated that little can be said 
about it, but it is very clear that the neck is shorter than that of No. 2 (fe- 
mur?), and there is a variation of nearly one-half in the degree of obliquity 
from the perpendicular of the shaft of the bone in which the two heads are 
set on ; that of No. 2 being more so than the other. They also differ in an- 
other respect. In measuring from the inferior part of the head, supposing 
both bones to be placed in an erect position, to the superior portion of the 
condyle, which is the best way in which I can ascertain their relative length ; 
No. 2 is longer in the shaft than the other bones, which, if they both belonged 
to the same individual, (and I think there is no sufficient reason to doubt it) 
would, according to thy conjecture, make it appear that one is the femur and 
the other the humerus. 

" The question next arises as to which of the bones either name is to be ap- 
propriated. No. 1 has the trochanter, which is very similar in shape to the 
femur marked No. 5 in the British Museum. No. 2 has none in its present 



ON BRITISH FOSSIL REPTILES. 139 

mutilated state, but on examining the posterior part of the shaft, where on the 
internal side one might expect to meet with some remains of the base of the 
trochanter, I find the surface of the bone concave, and it diverges much more 
than I should suppose it would do if it had merely been continuous with the 
returning surface from the anterior part of the bone, if there had been no 
trochanter interposed to disturb the otherwise greater rotundity of the shape. 

" This leads me to suppose that it once had one, and that it probably might 
ha,ve been formed like that in Nos. 1 and 2 in the British Museum. If they 
were not the bones of distinct animals, this might perhaps have been the 
case." Dated Horsham, Nov. 2nd, 1841. 

The characters of the articular extremities of the femur which are obscured 
by the mutilated condition of the large specimen, are beautifully shown in 
the femur of a young IguanodoH, obtained from a pit near Rusper, four miles 
north of Horsham. The rounded portion of the head extends inwards ; it is 
indented at its anterior part by the commencement of a longitudinal broad 
channel, which extends down uj)on the shaft : the articular surface is not con- 
fined to the inwardly produced head, but extends over the whole proximal 
horizontal surface of the femur, expanding as it approaches the outer part of 
the head. The articular surface is circumscribed by a well-defined linear 
groove, which separates it from the longitudinal striated surface of the shaft 
of the bone. At the posterior and external angle of the articular proximal 
end of the bone, a longitudinal column, separated by a longitudinal groove 
from the main shaft of the bone, falls into that shaft a little lower down the 
distal end : here the shaft expands and becomes flattened from before back- 
wards. The distal end is characterized by a deep and narrow anterior longi- 
tudinal groove, situated not quite in the middle, but nearer the internal con- 
dyle : there is a corresponding longitudinal groove on the posterior part of 
the distal end, which is wider than the anterior one, and in the middle of the 
bone, separating the two condyles, but inclining beneath, and, as it were, un- 
dermining the backward projecting part of the internal condyle ; this is much 
more prominent than the external one, which is traversed or divided by a 
narrow longitudinal fissure. The articular surface is irregular and tubercu- 
late. In. Lines. 

The lateral diameter of proximal end 2 8 

The lateral diameter of distal end 3 

Antero-posterior diameter of outer part of proximal end . 2 
Antero-posterior diameter of outer part of internal condyle 2 3 

The femur of the Iguana differs as widely from that of the Iguanodon as 
does that of the Monitor or any other Lacertiau reptile. The forms of the 
head and trochanter of the femur of the Iguana are just the reverse of those 
in the Iguanodon. The head of the femur in the Iguana is flattened from side 
to side, and its upper convex surface is extended from before backwards, ma- 
king no projection over the gentle concave line leading from its inner surface 
down to the inner condyle. In the Iguanodon the head is rounded and rather 
compressed from before backwards ; and is produced, as in Mammals, over 
the inner side of the shaft. 

In the Iguana the trochanter is compressed from before b.ackwards, and is 
separated by a wide and shallow groove from the oppositely compressed head : 
in the Iguanodon the trochanter is singularly flattened from side to side, and 
is applied to the outer side of the thick neck, from which it is separated by a 
deep and narrow fissure. The Iguana has no submedian internal process, and 
its distal condyles are slightly divided by a shallow depression. 

The circumference of the femur of the Iguanodon very nearly equals one- 
half its length : the circumference of the femur of the Iguana only equals one- 



140 REPORT — 1841. 

fourth its length : yet the femur of the Iguanodon equals the united length of 
eleven of its dorsal vertebrae, while that of the Iguana equals the united length 
of only six of its dorsal vertebrae. 

The femora of the Iguana stand out, like those of most other Lacertians, 
at right angles with the vertical plane of the trunk, which is rather slung upon 
than supported by those bones : but it is evident from the superior relative 
length and strength of those bones in the Iguanodon, from the different con- 
formation of the articular, especially the proximal extremities, and from the 
ridges and processes indicative of the powerful muscles inserted into the bone, 
that it must have sustained the weight of the body in a manner more nearly 
resembling that in the pachydermal Mammalia. As in some of the more 
bulky of these quadrupeds, the indication of the 'ligamentum teres 'is wanting 
in the head of the femur of the Iguanodon. 

The tibia of the Iguanodon equals the united length of nine of the dorsal 
vertebrae, while in the Iguana it does not exceed the united length of five dor- 
sal vertebrae, although it more nearly equals the femur in length than in the 
Iguanodon. The head of the tibia is more expanded and complicated by deep 
and wide grooves in the Iguanodon : the fibula is less expanded towards the 
distal end and less flattened against the tibia in the Iguanodon. 

The fibula of the small Iguanodon from the pit at Rusper, equals the an- 
tero-posterior extent of the spines of eight dorsal vertebrae of the same indi- 
vidual. This bone is 13 inches long, 2 inches across the proximal end, and 
6 lines across the distal end. 

Of the great Iguanodon from the Horsham quarry two metacarpal or me- 
tatarsal bones are preserved in natural juxtaposition : one exceeds the other 
by four inches, and measures 2 feet 6 inches ; the breadth of its distal end is 3 
inches 3 lines ; the shaft is compressed and subtrihedral ; its texture is spongy 
at the centre. The proximal end is expanded, with a nearly flat articular sur- 
face, the contour of which is broken by two longitudinal indentations : the 
distal end offers a well-sculptured trochlear articulation for the first phalanx. 
The bone of the Maidstone-^Ma«oc?ow(marked 7inthe figure above cited in the 
' Wonders of Geology') corresponds with the above described bones of the foot. 

Some of the phalanges, probably the middle ones, appear to have been sin- 
gularly abbreviated ; but they have not yet been discovered in such juxtapo- 
sition with undoubted Iguanodon's bones as to justify a more precise descrip- 
tion of their characters under the present head. 

The distal or ungual phalanges of the Iguanodon, although doubtless offer- 
ing certain modifications of form in different toes, are shown by those pre- 
served in the Maidstone Iguanodon, and others of much larger dimensions, 
found associated with the bones of the great Iguanodon of the Horsham 
quarry, to have had a less incurved, broader and more depressed form than 
in other known Saurians. Two of the largest ungual phalanges of the Hor- 
sham Ig^ianodon in Mr. Holmes's collection, are broad, subdepressed, with 
the curved vascular groove on each side, as in most other Saurians, with a 
slightly concave articular base, and terminating forwards in a round blunt 
edge ; the outer boundary of the lateral grooves forms, at the posterior end of 
the groove, a laterally projecting process, rendering this part of the phalanx 
broader than the articular extremity or basis. The following are dimensions 
of the largest of the two phalanges : — In. Lines. 

Length 5 4 

Breadth 3 2 

Breadth at articular end 3 

Depth at articular end 2 3 

The last dimension gradually diminishes to the distal end. 



ON BRITISH FOSSIL REPTILES. 141 

This phalanx is slightly bent downwards ; the under surface being concave 
longitudinally, but convex from side to side ; less so than on the upper surface. 
The under surface is rough ; the upper surface nearly smooth, except at the 
margin of the articular surface, on the projecting sides and at the distal ex- 
tremity, which is sculptured by irregular vascular grooves and holes. The 
phalanx has a slight oblique twist to one side, and is somewhat thinned off to 
that side on which the curved groove is longer than on the other side. 

In Mr. SauU's museum is an ungual phalanx of an Iguanodon, which nearly 
equals those from Horsham, and presents the same subdepressed form. The 
base is slightly convex transversely ; more concave vertically : the articular 
surface is faintly divided by a median vertical rising : the rounded edge of 
the articular surface is slightly raised, interrupted on both sides by the smooth 
shallow commencement of the curved vascular groove : this deepens and con- 
tracts as it extends forwards. The upper surface is convex longitudinally 
and transversely ; the lower surface is rather more convex transversely than 
the upper, but is slightly concave longitudinally. The upper and lateral sur- 
faces, for about an inch near the base, are deeply sculptured bj' large irregular 
longitudinal grooves and ridges ; the rest of the upper surface is impressed 
by fine interrupted longitudinal impressions ; but having, on the whole, a 
smooth appearance. The laminated superposition of the exterior compact 
portion of the bone is shown by the separation of portions of the layers of 
about one line in thickness. The under surface is more deeply impressed by 
cavities having reticulate elevations. The right aliform process begins 10 
lines from the articular surface, the left about 14 lines from the same part: 
their base is bounded below by slight impressions, and above by the lateral 
canals, which appear to sink into the bone. A few distant vascular grooves 
mark the upper surface of the bone, but more numerous larger ones are situated 
near the lateral canals and at the broken anterior end of the phalanx. The 
following are the dimensions of this bone : — In. Lines. 

Transverse diameter 3 5 

Transverse diameter of broken end 2 2 

Vertical diameter of base 2 7 

Vertical diameter of broken end 1 6 

Length to broken end 4 4 

it was probably more than 5 inches long when entire. 

The largest of the phalangeal bones in the collection of Wealden Rep- 
tiles in the British Museum, which from its breadth, slight degree of ob- 
liquity and vascular canals is referrible to the Iguanodon, is less than those 
just described. The phalanx in question (No.g^^^, Mantellian Collection) is 
conical, 4| inches long, probably 5 inches when entire ; but the apex is broken 
off": the longest diameter of the base or articular surface is 3 inches 3 lines : 
it is slightly and obliquely compressed, and very slightly curved, and from this 
circumstance, as well as from the obliquity of the base and its unsymmetrical 
figure, it probably belonged to the small outer or inner toe at the margin of 
the foot. Only a small part of the natural smooth articular surface is left, the 
rest appears to have been scraped away, so that the coarse cancellous structure 
of the middle of the bone is exposed. The free surface of the bone near the 
base is deeply sculptured by irregular longitudinal furrows, which served for 
the implantation of the articular ligaments. The rest of the free surface is 
tolerably smooth, except at the sides near the apex, where there are numerous 
oblique outlets for the large vessels and nerves supplying the secreting organ 
of the claw. The two lateral longitudinal curved grooves which characterize 
the claws of most Saurians are here well developed ; they commence, one at, 
the other near, the base ; are at first shallow, then deepen, and finally sink into 



142 REPORT — 1841. 

the substance of the bone about 1§ inch from its fractured apex. Below one 
of these canals there is a shallow smooth impression, corresponding no doubt 
with the margin of the claw. The under surface of the phalanx indicated by 
the concavity of the curved grooves is more convex transversely than the 
upper surface : the distance between the converging lateral grooves in this 
surface is one inch. 

Among the few other phalangeal bones from Dr. Mantell's collection in the 
British Museum, there is one (figured in the ' Wonders of Geology,' pi. iii. 
fig. 1, as belonging to the fore-foot of the Iguanodon) which differs in a 
marked manner from the specimens just described, being as much compressed 
from side to side as the Iguanodon's ungual phalanges are, for the most part, 
flattened from above downwards. One of these compressed phalanges must 
have been at least four inches in length ; it now measures three inches, with 
the extremity broken ofi"; it is 2 inches 8 lines in vertical diameter at the 
base, and only 1 inch 2 lines in the greatest transverse diameter. The 
phalanx is more curved downwards than any of the true Iguanodon's pha- 
langes, and it is traversed by a longer and shallower groove, the lower 
margin of which is not produced into a lateral aliform process, nor does the 
distal end of the groove sink into the substance of the bone. 

The ungual phalanges on both the fore and hind feet of the Iguana resem- 
ble this phalanx in form more than they do those of the Iguanodon. In the 
fore-foot of the Crocodile the ungual phalanx of the first or innermost toe is 
broad and flat, with lateral ridges, much resembling the depressed phalanges 
of the Iguanodon. The ungual phalanx of the third digit is of the same length, 
but is thinner in botli transverse and vertical directions, but is less so in the 
latter. It is not more curved. Still the difference (and this is the greatest 
that I can perceive in comparing the different ungual phalanges of the same 
individual Crocodile (Croc.oc?/tos)) is much less than that which is manifested 
between the depressed and the compressed phalanges hitherto referred to the 
Iguanodon. In the great proportion of the skeleton found near Maidstone 
are two phalanges which correspond in form with those enormous specimens 
found near Horsham, and with the small depressed claw-bones from Tilgate 
Forest, unquestionably belonging to the Iguanodon, and supposed by Dr. 
Mantell to be peculiar to the hind-foot of that Saurian. 

Size of the Iguanodon. — From the comparison, which the few connected 
portions of the skeleton of the Iguanodon enable us to make, between the 
bones of the extremities and the vertebral column, it is evident that the hind- 
legs at least, and probably also the fore-legs, were longer and stronger in pro- 
portion to the trunk than in any existing Saurian. One can scarcely suppress 
a feeling of surprise, that this striking characteristic of the Iguanodon, in com- 
mon with other Dinosauria, should have been, hitherto, overlooked ; since the 
required evidence is only an associated vertebra and long bone of the same 
individual, or a comparison of the largest detached vertebrae with the longest 
femora or humeri. This characteristic is, nevertheless, one of the most im- 
portant towards a restoration of the extinct reptile, since an approximation to 
a true conception of the size of the entire animal could only be made after the 
general proportions of the body to the extremities had been ascertained. 

But it is very obvious tliat the exaggerated resemblances of the Iguanodon 
to the Iguana have misled the Palaeontologists who have hitherto published 
the results of their calculations of the size of the Iguanodon; and, hence, the 
dimensions of 100 feet in length arrived at by a comparison of the teeth and 
clavicle of the Iguanodon with the Iguana, of 75 feet from a similar compa- 
rison of their femora, and of 80 feet from that of the claw-bone, which, if 
founded upon the largest specimen from Horsham, instead of the one com- 



On BRITISH FOSSIL REPTILES. 143 

pared by Dr. Mantell *, would yield a result of upwards of 200 feet for the total 
length of the Iguanodon, since the Horsham phalanx exceeds the size of the 
largest of the recent Iguana's phalanges by 40 times ! 

But the same reasons which have been assigned for calculating the bulk of 
the Megalosaurus on the basis of the vertebrae, apply with equal force to the 
Iguanodon. Now the largest vertebra of an Iguanodon which has yet been 
obtained does not, as has been before stated, exceed 4^ inches in length ; the 
most common size being 4 inches. The intervertebral substance is shown, by 
the naturally juxtaposed series of dorsal vertebrae in the Maidstone Iguano- 
don, to be not more than one-third of an inch in thickness. All the accurately 
determined vertebrae of the Iguanodon manifest the same constancy of their 
antero-posterior diameter which prevails in Saurians generally ; the discovery 
of the true character of the supposed Lacertian vertebrae, six inches in length, 
removes the only remaining doubt that could have attached itself to this im- 
portant element in the present calculation-}-. The cervical vertebrae of the 
Iguanodon, when discovered, if they prove to differ in length from the known 
dorsal and caudal vertebrae, will be, in all probability, somewhat shorter, as 
they are in the Hylaeosaur and in all known Crocodiles and Lizards. It re- 
mains, therefore, to discover the most probable number of the vertebrae of the 
Iguanodon, in order to apply their length individually to the estimate of the 
length of the entire body. The structure of the vertebrae and the ribs, and 
especially the variation in both structure and size which the ribs of the Igua- 
nodon, already obtained, demonstrate to have prevailed in the costal series, 
render it much more probable that the number of the costal vertebrae would 
resemble that of the Crocodiles than that of the Scincus or other Lizards with 
unusually numerous dorsal vertebrae, and which possess ribs of a simple and 
uniform structure, and of nearly equal size. The most probable number of 
vertebrae of the trunk, from the atlas to the last lumbar inclusive, calculated 
from Crocodilian analogies, would be 24 vertebrae ; which is also the number 
possessed by the Iguana. 

Twenty-four vertebrae, estimated with their intervertebral spaces at 5 inches 
each, give 10 feet ; if to this we add the length of the sacrum, viz. 17 inches, 
then that of the trunk of the Iguanodon would be 11 feet 5 inches; which 
exceeds that of the Megatherium. If there be any part of the skeleton of 
the Iguana which may with greater probability than the rest be supposed 
to have the proportions of the corresponding part of the Iguanodon, it is the 
lower jaw, by virtue of the analogy of the teeth and the substances they are 
adapted to prepare for digestion. Now the lower jaw gives the length of the 
head in the Iguana, and this equals the length of six dorsal vertebrae, so that 
as 5 inches rather exceeds the length of the largest Iguanodon's vertebra yet 
obtained, with the intervertebral space superadded,onthis calculation the lensjth 
of the head of the \a,rgest Igutmodon must have been 2 feet 6 inches. In the 
description of the caudal vertebrae it has been shown that theIguanodo7i could 
as little have resembled the Iguana in the length of its tail;]:, as in the anato- 
mical characters of any of the constituent vertebra of that part : the chano-es 
which the series of six caudal vertebrae present in the length and form of the 
spinous processes, and in the place of origin of the transverse processes, indi- 
cate the tail to have been shorter in the Iguanodon than in the Crocodile. 
Assuming, however, that the number of caudal vertebrae of the Iguanodon 
equalled that in the Crocodile, and alloAving to each vertebra with its inter- 

* Mantell, Geology of the South-east of England, -p. 314. 
t See p. 92 of the present Report. 

X See also the judicious remarks hy Dr. Buckland to the same effect, Bridgewater Treatise, 
p. 244. 



144 REPORT— 1841. 

■vertebral space 4|- inches, we obtain the length of 12 feet 6 inches for the 
tail of the Iguanodon. On the foregoing data, therefore, we may liberally 
assign the following dimensions to the Iguanodon : — Feet. 

Length of head, say 3 

Length of trunk with sacrum 12 

Length of tail 13 

Total length of the Iguanodon ... 28 
The same observations on the general form and proportions of the animal, 
and its approximation in this respect to the Mammalia, especially the great 
extinct Megatherioid or Pachyd.ermal species, apply as well to the Iguanodon 
as to the Megalosaurus. 

Order LACERTILIA. 

Leaving now the gigantic Saurians constituting the order Dinosauria, 
above characterized, and establishing in several important points of their os- 
teological structure the transition from the Crocodilian to theLacertian order, 
I next proceed to notice the remains of those extinct Reptiles, which manifest 
in the enduring parts of their organization a closer affinity to the extensive 
and varied order of the smaller and lower organized Saurians which are dis- 
tributed over all the warmer parts of the present surface of the earth. 

The ancient representatives of the Lacertian order are for the most part of 
gigantic size, and deviate, like many of the ancient Crocodilians, from ex- 
isting Lizards, by very remarkable characters of the vertebrae, teeth, and 
dermal bones. 

Genus Mosasaurus. 

Commencing with the species which retain the ordinary ball and socket 
structure of the vertebrae, the gigantic Mosasaurus first claims attention. Two 
vertebrae which have the anterior articular facet concave,' the posterior con- 
vex, and the other characters of this genus, are preserved in the Mantellian 
Collection. They are from the chalk formation in Sussex, and have been re- 
ferred by Dr. Mantell to the genus Mosasaurus. 

Genus Leiodon. 

Hitherto no teeth corresponding with those of the Mosasaurus Hoffmanni 
of St. Peter's Mount near Maestricht, have been discovered in the chalk 
formations of England. The teeth of the Pliosaur have, in some instances, 
been mistaken for those of the Mosasaur. 

The teeth from the chalk of Norfolk, figured and described in my 'Odonto- 
graphy*' as representatives of the gen\xs Leiodon, make the nearest approach 
to the characters of those of the Mosasaurus. They are about one half the 
size of the maxillary teeth of the Mosasaurus Hoffmanni, and difi"er more es- 
sentially in having their outer side as convex as the inner side, the transverse 
section of the crown being elliptic, the pointed extremities of the ellipse cor- 
responding with two opposite longitudinal trenchant ridges, which separate 
the outer from the^ inner side of the tooth. The crown expands at the base, 
which is circular, and is anchylosed to a conical process, developed from the 
broad alveolar margin of the jaw. In this, which is termed the " acrodoi^t " 
type of dentition, the Leiodon corresponds with the Mosasaur. It is proba- 
ble that the vertebrae of the two extinct reptiles may have corresponded in 
form ; and it is possible that those from the English chalk, hitherto referred 
to the Mosasaurus, may appertain to the same species as the teeth here de- 

* P. 261, pi. Ixxii. 



ON BRITISH FOSSIL REPTILES. 145 

scribed. From tlie correspondence in the general structure, smootli external 
surface, and mode of attachment of tlie teeth between the Maestriclit Mosa- 
saur and the English Leiodon, it may be concluded that the latter reptile had 
the same affinity to the Lacertian type, which the Mosasaur so strikingly 
manifests in the presence of pterygoid teeth. 

Genus Kaphiosaurus. 

Under this name I propose to notice a small and hitherto undescribed genus 
of Lacertians, from tlie chalk I'ormations near Cambridge, indicated by a por- 
tion of the lower jaw, containing twenty-two close-set, awl-shaped teeth an- 
chylosed by their bases to an outer alveolar parapet of bone, and thus corre- 
sponding with the pleurodout type of dentition among the Lizards. 

To the same genus may belong a beautiful specimen in the museum of Sir 
Philip Egerton, consisting of a series of twenty dorsal, two lumbar, two 
sacral, and a few of the caudal vertebrae, with the pelvic bones, from the chalk 
near Maidstone, which correspond with the jaw of the Raphiosaiirus in size. 
The vertebral characters are essentially those of the modern Lacertians ; but 
the absence of extremities and teeth prevents the generic affinities being ac- 
curately determined. 

It is interesting to find this second- instajiee of the ' procoelian ' type of 
vertebrae — or those with the anterior cup and posterior ball — in the chalk 
formations, below which I have not met with any instance of a Reptile agree- 
ing with the existing species in this structure. 

Pleurodont Eocene Lizard. — Among the fossils obtained by Mr. Col- 
chester from the Eocene sand, underlying the Red Crag at Kyson, or King- 
ston, in Suffolk, the existence of a lizard, about the size of the Iguana, is in- 
dicated by a part of a lower jaw, armed with close-set, slender, subcylindri- 
cal, antero-posteriorly compressed teeth, attached to shallow alveoli, and with 
their bases protected by an external jjarapet of bone. The fragment of jaw 
is traversed by a longitudinal groove on the inside, and perforated, as in most 
modern lizards, by immerous vascular foramina along the outside. The teeth 
are hollow at their Ijase. 

Scincoid Oolite Lizard. — A small Lacertian is indicated by remains dis- 
covered in the celebrated oolite at Stonesiield. The most intelligible of these 
is a femur, ten lines in lengtli, having a hemispherical head supported on 
a short subcompressed neck, on each side of the base of which there is a 
strong conical trochanterian process : the middle of the shaft is cylindrical, 
and soon expands to form a broad distal extremity. This shape of the bone 
proves it not to be the young of any of the great Saui'ians hitherto discovered 
at Stonesfield (the expansion of the distal end removes it from the Ciielonian 
reptiles), but indicates its affinity to the Scincoidian lizards, the largest forms 
of which, it may be remarked, now exist in Australia, where they are asso- 
ciated with Araucaria: and cycadeous plants, with living Terebratulce, and Tri- 
gonicE, and with the peculiar marsupial quadrupeds ; the remains of all which 
forms of organized beings characterize the same stratum and locality as that 
in which the present extinct Lacertian was found. 

No vertebras of tlie procoelian type have hitherto Iieen discovered in the 
oolite, and it is most probable that those of the small Lacertian here indica- 
ted, agree with those of most other extinct Saurians of the secondary forma- 
tions in having both articular extremities subconcave. 

Genus Riiynchosaurus. 

The biconcave structure unquestionably characterizes the vertebra? of the 
small Lacertian from the new red sandstone quarries near Shrewsbury, on 
which the M'ell-mt\rkeU and distinct genus Rhynchosaurus is founded. 

1841, I, 



146 REPORT — 1841. 

For the opportunity of examining the rare and interesting remains of the 
Rhynchosaurus I am indebted to Dr. Ogier Ward of Shrewsburj^, and to the 
Council of the Natural History Society of that town, in the museum of which 
many of the fossils here described are deposited. 

They occur at the Grinsill quarries, in a fine-grained sandstone, and also in 
a coarse burr-sandstone ; in the latter are imbedded some vertebree, portions 
of the lower jaw, a nearly entire skull, fragments of the pelvis and of two 
femora: in the fine-grained sandstone, vertebrae, ribs, and some bones of the 
scapular and pelvic arches are imbedded. The bones present a very brittle 
and compact texture ; the exposed surface is usually smooth, or very finely 
striated, and of a light blue colour. The sandstones containing these bones 
occasionally exhibit impressions of footsteps which resemble those figured in 
the Memoir by Messrs. Murchison and Strickland, Geol. Trans., 2nd Series, 
vol. V. pi. xxviii. fig. 1, but differ in the more distinct marks of the claws, the 
less distinct impression of a web, the more diminutive size of the innermost toe, 
and an impression corresponding with the hinder part of the foot, which Dr. 
Ward compares to " a hind-toe pointing backwardt-, that, like the hind-claw 
of some birds, only touched the ground with its point, which was armed in 
some of the foot-prints with a claw still longer than those of the fore-toes *." 
The foot-prints are likewise more equal in size and likewise in their intervals 
than those figured by Messrs. Murchison and Strickland : they measure from 
the extremity of the outermost or fifth toe to that of the innermost or first 
rudimental toe, about one inch and a half. They are the only foot-prints that 
have as yet been detected in the new red sandstone quarries at Grinsill. 
, I proceed now to describe the fossil bones, respecting which Dr. Ward ob- 
serves, " as they have always been found nearly in the same bed as that im- 
pressed by the footsteps above described, I am induced to believe that these 
are the bones of the same animal :" an opinion, Avhich, from the correspond- 
ence between the bones and the foot-prints in size, is, at least, highly probable. 

Vertebrce. — Both surfaces of the centrum are concave, and are deeper than 
in the biconcave vertebree of the extinct Crocodilians ; the texture of the cen- 
trum is compact throughout. The two lateral surfaces join the under surface 
at a nearly right angle, the transverse section presenting a subquadrate form, 
with the angles rounded off: the under surface and sides are regularly con- 
cave longitudinally. 

The neural arch is anchylosed with the centrum, without trace of suture, as in 
most lizards : it immediately expands and sends outwards from each angle of its 
base a broad triangular process with a flat articular surface ; the two anterior 
surfaces look directly upwards, the posterior ones downwards ; the latter are 
continued backwards beyond the posterior extremity of the centrum; the tu- 
bercle for the simple articulation of the rib is situated immediately beneath the 
anterior oblique process. So far the vertebrae of the Rhynchosaurus, always 
excepting their biconcave structure, resemble the vertebrae of most recent li- 
zards. In the modification next to be noticed, they show one of the verte- 
bral characters of the Dinosauria. A broad obtuse ridge rises from the upper 
convex surface of the posterior articular process and arches forwards along 
the neural arch above the anterior articular process, and gradually subsides 
anterior to its base : the upper part of this arched angular ridge forms, Avith 
that of the opposite side, a platform, from the middle line of which the spi- 
nous process is developed. This structure is not present in existing lizards; 
the sides of the neural arch in their vertebrae immediately converge from the 
articular processes to the base of the spine, without the intervention of an 
angular ridge formed by the side of a raised platform. The base of the spinous 
* Extract of a letter, dated Shrewsbury, November 27th, 1840. 



ON BRITISH FOSSIL REPTILES. 147 

process in the Rhynchosaur is broadest behind, and commences there by two 
roots or ridges, one from the upper and back part of each posterior articular 
process : they meet at the posterior part of the summit of the neural arch, 
whence the spinous process is continued upwards as a simple plate of bone, 
its base extending forwards along about two-thirds of the length of the plat- 
form, which then again divides into two ridges, which diverge from each other 
in slight curves to the anterior and external angles of the neurapophyses. The 
interspace of the diverging anterior crura of the base of the spine is occupied 
by a triangular fossa, not continued into the substance of the spine ; this 
fossa is bounded below by u horizontal plate of bone extended over the an- 
terior part of the spinal canal, and terminated by a convex outline. The 
anterior margin of the spinous process is thin and trenchant; the height of 
the spine does not exceed the antero- posterior diameter of its base ; it is 
obliquely rounded off. The spinal canal sinks into the middle part of the 
centrum and rises to the base of the spine, so that its vertical diameter is twice 
as great at the middle as at the two extremities : this modification resembles 
in a certain degi'ee that of the vertebrae of the Palaosaurus from the Bristol 
conglomerate. The following are dimensions of the most perfect of the dorsal 

vertebrae of the Rhvnchosaurus : — t • 

•^ Lines, 

The length of the centrum 5^ 

Height of the articular end 3 

Breadth of the articular end 2f ^ 

From the lower margin of the posterior extremity of the centrum to 1 _ 

the posterior part of the base of the spine j 

From the lower margin of the posterior extremity of the centrum to 1 „ 

the summit of the spine j 

Antero-posterior extent of base of spine 4 

Breadth of the neural arch, from the outer margin of one anterior! _i 

articular process to that of the opposite side J 2 

Breadth of the neural arch at the interspace between the anterior and 1 . 

posterior oblique processes J 

Breadth of the neural arch across the middle of the spinal platform . 2 

Skull. — The most complete specimen yet obtained of this instructive part 
of the skeleton of the Rhynchosaurus, is imbedded in a portion of the coarse- 
grained sandstone from the Grinsill quarries. The lower jaw is in its natural 
position, as when the mouth is shut, showing that the parts had not been dis- 
located from the time of the death of the animal to its becoming imbedded in 
the sand. 

The skull presents the form of a four-sided pyramid, compressed laterally, 
and with the upper facet arching down in a graceful curve to the apex, which 
is formed by the termination of the muzzle. The very narrow cranial box; 
the wide temporal fossae on each side, bounded posteriorly by the parietal and 
the mastoid bones, and laterally by strong compressed zygomata ; the long 
tympanic pedicle, descending freely and vertically from the point of union of 
the posterior transverse and zygomatic arches, and terminating in a convex 
pulley for the articular concavity of the lower jaw ; the large and complete 
orbits ; and the short, compressed, and bent down maxillae, — all combine to 
prove the i'ossil to belong to the Lacertian division of the Saurian order. The 
mode of articulation of the skull with the spine cannot be determined in the 
present specimen, but the lateral compression and the depth of the skull, the 
great vertical breadth of the superior maxillary bone, the smaller relative size 
of the temporal spaces, the great vertical breadth of the lower jaw, all prove 
that it does not belong to a reptile of the Batrachian order. The shortness 

l2 



148 REPORT — 1841. 

of the muzzle and its compressed form, equally remove it from the Croeodili- 
ans. No Clieloniau has the tympanic pedicle so long, so narrow, or so freely 
suspended to the posterior and lateral angles of the cranium. 

The general aspect of the skull differs, however, from that of existing Lacer- 
tians, and resembles that of a bird or turtle, which resemblance is increased 
by the apparent absence of teeth. The intermaxillary bones, moreover, are 
double, as in Crocodiles and Chelonians, but, with this exception, all the essen- 
tial characters of the structure of the skull are those of the Lizard. 

Of the proper walls of the cerebral cavity, the portion formed by the parietal 
and frontal bones is exposed ; the parietal is traversed longitudinally by a thin, 
but high, median crest; the part of the bone forming the sides of the small 
cerebral cavity are convex, and the breadth of the bone diminishes towards 
the occiput ; here it divides into two branches, which pass outwards more 
transversely than in existing lizards. There is no perforation either in the 
parietal bone or in the coronal suture. At the anterior part of the parietal 
crest two lines diverge from each other at a right angle to the upper part of 
the oi'bit, and separate the post-frontals. A nearly transverse suture divides 
the fore-part of the parietal from the post-frontals. The median frontal bone 
is single, like tiiat of the New World Monitors ( Thorictes, Tejus, <Src.) and the 
Iguanse, and not divided, as in the Varanians. It expands slightly as it ad- 
vances towards the fore-part of the orbits : the oblique lines dividing the 
median frontals from the post-frontals, and the supraorbital ridges are raised, 
so that the interspace is slightly concave, and the surface is also broken by 
irregular elevations and depressions. Each post-frontal is divided by a nearly 
transverse suture. The posterior frontal completes the upper and outer part 
of the orbit by a thin, well-defined, curved plate ; an irregular obtuse ridge 
descends in a nearly vertical direction behind this plate, and then the posterior 
frontal contracts and is extended backwards in the form of along compressed 
process, gradually terminating in a point, which overlaps the zygomatic bone. 
This bone forms the medium of union between the long posterior frontal and 
the mastoid. 

The tympanic bone presents a slight sigmoid flexure, and is expanded trans- 
versely at its distal extremity ; its posterior surface is exposed, which is con- 
vex and rounded, and continued externally in the form of a thin plate, which 
is concave behind. The thick convex stem divides near the lower end into 
two ridges, which diverge, like the condyles of a humerus, and intercept the 
trochlea, on Avhich the concave articulation of the lower jaw plays. The tym- 
panic trochlea is convex from behind forwards, concave from side to side. 
The orbit is large, nearly circular in form, and its bony frame is complete ; 
this is formed above by the median, anterior, and posterior frontals ; before 
by the anterior frontal and lachrymal; below by the malar; and behind by the 
malar and posterior frontal. 

The malar bone, as in most lizards, is long, slender, and bent upon itself, 
but its external surface is unusually concave, the orbital plate bending out- 
wards like the corresponding rim formed by the frontal bone. The anterior 
or horizontal branch of the malar gradually tapers to a point which is Avedged 
in between the lachrymal and maxillary bones. The posterior branch ascends 
at nearly a right angle, and is apjilied obliquely to the posterior part of the 
descending process of the posterior frontal. At the angle between the two 
portions of the malar a process is continued backwards for about half an inch, 
but its extremity is broken off. The lachrymal bone presents the same relative 
position and size as in the Thorictes, Lacerta, and most lizards ; a tubercle 
rises from about the middle of its external surface. The superior maxillary 
is a broad vertical triangular plate of bone, with a smooth external surface ; 



ON BRITISH FOSSIL REPTILES. 149 

the alveolar borxler projects externally like a ridge, above -wliich the bone is 
slightly concave. This ridge appears to be slightly dentated ; it overlaps 
the corresponding alveolar border of the lower jaw. The posterior and su- 
perior margin of the maxillary is slightly concave, and joins the malar and 
lachrymal bones and a small part of the prefrontal : the anterior superior mar- 
gin joins the upper half of the elongated intermaxillary, which divides it from 
the nasal bones and the external nostril ; the lower side or base of the triangle, 
M'hich forms the alveolar border, is convex. 

The most singular character of the cranium of the present fossil genus is 
afforded by the intermaxillary bones. These, in their length and regular 
downward curvature, give to the fore-part of the skull the physiognomy of 
that of a parrot or accipitrine bird, but they differ essentially from both those 
of the bird and lizard in being distinct from each other throughout their whole 
length, and in gradually diminishing to their inferior extremity, which is not 
expanded and continued laterally to form any part of the alveolar border of 
the upper jaw. Each intermaxillary bone is a slender, subcompressed, elon- 
gated bone, bent so as to describe a quarter of a circle ; the upper half is 
thinner, but rather broader than the lower half, and is wedged in between 
the superior maxillary, frontal and nasal bones ; the lower half, which is some- 
what narrower but thicker, and is subcylindrical, projects freely doivnwards 
beyond the superior maxillary bone; the deep anterior extremity or com- 
pressed symphysis of the lower jaw is applied to the posterior surface of these 
produced extremities of the two intermaxillaries, when the mouth is closed. 
The two intermaxillaries converge towards each other from their posterior 
origins, and are in close contact with each other, where they form the singular 
curved projecting beak. 

The external nostril is single and situated between the upper diverging ends 
of the intermaxillaries, but a fracture of the fossil at this part prevents the 
precise form of this aperture, or the mode of termination of the nasal bones, 
from being determined. The nasal bones, if not actually absent in the present 
fossil, as in most Chelonians, must have been extremely small, as in the Cha- 
meleons. 

The lower jaw is of considerable depth, and exceeds, as in most Saurians, 
the length of the cranium. The articular cavity is deep and wide ; the angle 
of the jaw is broken off directly behind this cavity on the left side, but is con- 
tinued backwards beyond it for more than half an inch on the right side. The 
ramus gradually expands in the vertical direction, and becomes thinner from 
side to side, as it advances forwai'ds to about its middle part, which is just 
behind the orbit, where it measures 11 lines in depth; it then begins gra- 
dually to diminish vertically to the symphysis, which again slightly increases 
vertically to its termination, which is obliquely truncated, much compressed 
laterally, and applied against the deflected extremities of the produced inter- 
maxillaries. The posterior half of the maxillary ramus is slightly convex ex- 
ternally, the anterior narrower part is slightly concave ; the superior margin 
describes a slight but graceful sigmoid curve, convex posteriorly, and con- 
cave anteriorly, where it is applied to the convex alveolar border of the upper 
maxillary bone, to the inner side of which it is closely adapted. The alve- 
olar border forms an external, convex, projecting ridge, analogous to that of 
the upper jaw. The composite structure of the lower jaw is very clearly dis- 
played in the fossil. The articular piece is short, but is continued forward 
as a slender process below the angular piece, as in the Varamis; the angular 
piece is relatively larger than in the Varanus, and presents nearly the same 
proportions as in the Thorictes. The supra-angular is larger, and occupies 
the proportion of the jaw formed by the supra-angular and coronoid elements 



J50 REPORT 1841, 

in TJwrictes and other lizards : the opercular element extends further upon 
the outside of the jaw from its lower margin than in the existing lizards ; the 
Thorict.es again, in this respect, coming nearest to the Rhynchosaurus : the 
dentary element constitutes the rest of the outer part of the ramus, but not 
the slightest trace of teeth is discernible. 

The present singular and highly interesting cranium seems to have been 
preserved with the mouth in the naturally closed state, and the upper and 
lower jaws are in close contact. In this state we must suppose that they were 
originally buried in the sandy matrix which afterwards hardened around them; 
and since lizards, owing to the unlimited reproduction of their teeth, do not 
become edentulous by age, we must conclude that the state in which the 
Rhynchosaurus was buried, with its lower jaw in undisturbed articulation with 
the head, accorded with its natural condition, while living, so far as the less 
perishable hard parts of its masticatory organs were concerned. Neverthe- 
less, since a view of the inner side of the alveolar border of the jaws has not 
been obtained, we cannot be assured of the actual edentulous character of 
this very singular Saurian ; for in the genera Agama and Chameleo the den- 
tal system, seen only from the outside of the jaws, is represented by mere den- 
tations of the alveolar border, and the anchylosed bases of the teeth, the crowns 
of which really form the dentations, are recognizable only by an inside view. 
The indications of the dental system are at any rate more obscure in the 
Rhynchosaurus than in any existing Lacertian ; the dentations of the upper 
jaw are absolutely feebler than in the Chameleon, and no trace of them can 
be detected in the lower jaw, where they are strongest in the Chameleon. 
The absence of the coronoid process in the Rhynchosaurits, which is conspi- 
cuously developed in all existing lizards, corresponds with the unarmed con- 
dition of the jaw, and the resemblance of the Rhynchosaurus in this respect 
to the Tesludo ( Chelys) ferox, would seem to indicate that the correspond- 
ence extended to the toothless condition of the jaws. The resemblance of 
the mouth to the compressed beak of certain sea-birds, the bending down of 
the curved and elongated intermaxillaries, so as to be opposed to the deep 
symphysial extremity of the lower jaw, are further indications that the ancient 
Rhynchosaur may have had its jaws encased by a bony sheath, as in birds 
and turtles. 

A small flattened triangular plate, which adhered to the posterior part of 
the skull, was suspected by Dr. Ward to be a tooth ; it appeared to me, from 
the character of the exposed surface, to have at least equal claims to be re- 
garded as a dermal scute. In prepai'ing the mould of the cranium this part 
was detached and lost, a circumstance M'hich I have much regretted, since it 
prevented my applying to it the test of a microscopical examination. 

I proceed now briefly to notice the other portions of the skeleton, which, 
from their size, texture, and community of stratum and locality, are with much 
probability referable to the Rhynchosaurus. 

Considerable portions of two rami of two distinct lower jaws, in portions of 
sandstone from the Grinsill quarries, show the same structure as that of the 
jaw in the cranium above described ; the thick edentulous alveolar border is 
bounded below on the outside by the longitudinal channel ; the lower border 
of the ramus is thick and smoothly rounded, it is somewhat abruptly con- 
stricted immediately behind the deflected extremity or symphysis. The struc- 
ture of the bone is very compact ; the fractured end demonstrates the large 
cavity, common in reptiles, which is included between the opercular and 
dentary pieces. 

One piece of fine-grained sandstone contains a considerable proportion of 
four of the dorsal vertebrae in a connected chain, which measures 1 inch 10 



ON BRITISH FOSSIL REPTILES. 151 

lines. Near this chain of four and a smaller part of a fifth vertebra, there 
are portions of four ribs. These have a single, not a bifurcated head ; they 
are subcompressed, slightly and pretty uniformly curved, and grooved longi- 
tudinally on both sides ; the longest portion of rib measures 2 inches, follow- 
ing the curvature. The same fragment of sandstone contains three flat bones, 
which offer several striking modifications, whether they be compared with the 
constituents of an os innoniinatum or of the scapular arch. 

The most entire of the three bones consists of a thicker articular end ; 
a long, broad and thin plate, forming the body of the bone ; and a mode- 
rately long trihedral process, given off from the convex margin near the 
articular end. In these characters the comparative anatomist conversant 
with the modifications of the skeleton in recent and extinct Saurians will re- 
cognize a resemblance to the scapula of the Iguanodou and Hylaeosaur, in 
a minor degree to the ischium of the Crocodile, and somewhat more remote- 
ly, to the pubis of the Tortoise. The trihedral process, in the second compa- 
rison, would match the anterior pubic process of the Crocodile's ischium, 
but the entire bone would differ from that of the Crocodile in the slender- 
ness of the pubic process, in the greater breadth and less length of the body 
of the bone, and in its extreme thinness ; it increases in thickness, however, 
as in the Crocodile's ischium, towards the articular end. The correspond- 
ence of the trihedral process of the bone in question with the long spinous 
process of the Chelonian pubis, is less close than the one just discussed. If 
the present well-marked bone of the Rhynchosaur be regarded as a scapula, 
it is to that bone in the Dinosauria that it offers most resemblance ; and the 
prismatic process would then correspond with the one sent off from the an- 
terior part of the coracoid articular surface in the scapula of the Hylaeosaur 
and Iguanodon. It is the concavity at the neck of the bone, at the side oppo- 
site that from which the process is sent, which gives it a nearer resemblance 
to the Dinosaurian scapula than to the Crocodilian ischium ; it differs from 
the scapula of tlie Crocodile in having the posterior margin, beyond the neck, 
straight instead of convex ; the corresponding margin in the ischium being 
concave. The blade of the bone, considered as scapula, is broader and shorter 
than in either the Dinosaurs or Crocodiles. Its outer surface is slightly con- 
vex : supposing it to be placed vertically upon the thicker articular end, the 
prismatic process is directed forwards and downwards. There are a few small 
pits or inequalities near the neck or thick articular margin in the present fossil. 
The outer surface of the plate is marked with extremely fine striae, radiating 

from the neck. , , • 

In. Lm. 

Length of the bone 18 

Breadth of neck 5^ 

Breadth of base 10 

Length of trihedral process 8 

Coracoid. — The remains of a thin and broad plate of bone, attached by a 
short neck to an apparently articular thickened head or process, might be 
compared with a coracoid, as it resembles, so far as it is preserved, the cora- 
coid of lizards, more than it does any other known bone; there is not, how- 
ever, the perforation near the articular surface. The breadth of the neck is 
6 lines, that of tiie body of the bone which remains 13 lines ; the length, or 
diameter at right angles to the above, is 10 lines ; the bone is tliinned off to 
an edge, which is gently convex. 

Humerus. — A tiiird bone, imbedded in the same piece of sandstone at a 
little distance from the preceding, is expanded at both extremities, contracted 
and twisted in the middle ; one of the expanded extremities, apparently the 



152 REPORT — 1811. 

proximal end, is nearly entire; it terminates by an irregular convex border, 
not thinned off to an edge, but adapted to the formation of a joint, and to the 
attachment of cartilage. The exposed surface of the expanded head is con- 
cave from side to side., somev. hat resembling the expanded and bent pubic 
plate in lizards. The opposite extremity is broken across ; it shows the com- 
mencement of a slight longitudinal ri(lge near its middle part. This bone 
bears most resemblance to a humerus, but I am at present unable to deter- 
mine it unequivocally. If compared v.ith the left pubis of Lacertians, the 
entire and bent extremity corresponds with the median portion of that bone ; 
but the middle part or stem is much longer in the fossil, and the broken end, 
which would agree with the acetabular end of the pubis, is too thin to have 
entered into the formation of such a cavity in the fossil ; it likewise wants the 
perforation which characterizes the pubis in lizards. The same thinness and 
imperforate condition of the fractured end oppose the comjjarison of the pre- 
sent bone with the coracoid of the Crocodile. 

In. Lin. 

Length of this bone as far as complete 19 

Breadth of middle 3 

Breadth of entire expanded extremity 10 

In the slab containing the above-described bones, there are other fragments 
of bone, but too small and imperfect for profitable description. Those of 
which I have endeavoured to make the form and analogies intelligible, though 
evidently peculiar, as might be expected in a Saurian with so strange a head, 
and perhaps with a hind-toe directed backwards as in birds, may be regarded 
as, most probably, constituents of a strong and well-developed pectoral arch, 
and a humerus ; and they indubitably indicate a mechanism for locomotion 
on land, which would well agree with that of the animal that has left the im- 
pressions of its footsteps upon the same sandstone. 

Radius and Ulna. — Another piece of coarse-grained sandstone from the 
same quarry contains a series of seven or eight vertebrfe in a very fragmentary 
state, also two or three ribs, rather more slender and not so distinctly grooved 
as in the fine-grained slab, and the proximal extremities of two long bones, 
which may be best compared with the radius and ulna. The shaft of the 
radius is more slender than that of the ulna ; one side is flat, the other con- 
vex ; it expands and assumes a subtrihedral figure, by the development of a 
slight longitudinal ridge ; its proximal end is conipi-Cfscd and more suddenly 
expanded ; its breadth is 2\ lines, that of the shaft of the bone is 1 line. The 
impression, partly broken away in the stone, indicates the greater expansion 
of the distal end of this bone, with a length of 1 inch 3 lines. The proximal 
end of the ulna has a distinct trihedral figure, and the expanded extremity is 
produced backwards, so as to indicate the olecranon; the breadth of the head 
is 4 lines, that of the middle of the shaft is 2^ lines. There is a portion of a 
broad and flat bone in this piece which may have belonged to the scapular 
arch. 

Ilium. — In another piece of stone, with the other portion of the same chain 
of five vcrtebrcB, there is a broad and flat bone, apparently terminating in a 
long narroAv process at one end, which may be an ilium ; its length is indi- 
cated to be at least 1 incii 7 lines. 

Femora. — A thin piece of burr or coarse-grained sandstone contains the 
articular end of a broad and flat bone, in which the raised oblong surface of 
the joint is divided by a smooth channel, and may be compared with the co- 
tyloid portion of the ilium ; the same piece of stone contains the shafts of two 
long bones, most probably femora. The length of the most perfect of these 
is 2 inches, and this does not include the distal end ; the diameter of the 



ON BRITISH FOSSIL, UEPTILES. 153 

middle of the shaft Is 2-^ lines ; the siuface of the preserved middle part shows 
tlie shaft to have been somewhat angular ; the compact outer wall of the bone 
is about a quarter of a line thick ; a large medullarj^ cavity extends the whole 
length of the sliaft, agreeing with the indications of terrestrial habits yielded 
by the bones before described ; the extremities of the femora are spongy, but 
nuich deconijjosed and stained with iron-mould. 

There are few genera of extinct reptiles of M'hich it is more desirable to 
obtain the means of determining the precise modifications of the locomotive 
extremities than the lilajnchosaurus. The fortunate preservation of the skull 
has brought to light modifications of the Lacertine structure leading towards 
Ciwlonia and Birds, which before were unknown ; the vertebra likewise ex- 
hibit very interesting deviations from the Lacertian type. The entire recon- 
struction of the skeleton of the Ehynchosaurus may be ultimately accom- 
plished, if the same interest in the collection and preservation of the fossils 
of the Grinsill quarries be continued, as has already produced so important 
an accession to Palajontology through the well-directed zeal of Dr. Ogier 
Ward and other members of the Literary and Scientific Association at 
Shrewsbury. 

Thecodonts. 

Among the inferior or squamate Saurians there are two leading modifica- 
tions in the mode of attachment of the teeth, the base of which may be either 
anchylosed to the summit of an alveolar ridge, or to the bottom of an alveolar 
groove, and supported by its lateral wall. These modifications are indicated 
respectively by the terms " acrodont" and " pleurodont." A third mode of 
fixation is presented by some extinct Saurians, which, in other parts of their 
organization, adhere to the squamate or Lacertine division of the order, the 
teeth being implanted in sockets, cither loosely or confluent with the bony 
walls of the cavity; these I have termed the "thecodont"* Lacertians: the 
most ancient of all Saurians belong to this group. 

Thecodontosaurus, Riley and Stutchbury. — In the dolomitic conglomerate at 
Redland near Bristol, a formation considered to belong to the oldest or lowest 
division of the new red sandstone scries, remains of reptiles have been dis- 
coveied by Dr. Riley and Mr. Stutchbury f, which are allied in the form of 
their teeth to the typical Varanian Monitors, but differ in having the teeth 
imbedded in distinct sockets ; to this condition, however, the Varani, among 
the squamate Saurians, make an approacii in the shallow cavities containing 
the base of the teeth along the bottom of the alveolar groove. 

In the ancient extinct genus in question the sockets are deeper, and the 
inner alveolar wall is nearly as high as the outer one; the teeth are arranged 
in a close-set series, slightly decreasing in size towards the posterior part of 
the jaw ; each ramus of the lower jaw is supposed to have contained twenty- 
one teeth. These are conical, rather slender, compressed and acutely pointed, 
with an anterior and posterior finely-serrated edge, the serratures being di- 
rected towards the apex of the tooth, as in the genus Bhopalodon of G. 
I'ischer; the outer surface is more convex than the inner one; the apex is 
slightly recurved ; the base of the crown contracts a little to form the fang, 
which is subcylindrical. The pulp-cavity remains open in the base of the 
crown. In their microscopic structure, the teeth of the Thecodontosaurus 
closely correspond with that of tlie teeth of the Varamis, Monitor, and Me- 
galosaurus. The body of the tooth consists of compact dentine, in which the 
calcigerous tubes diverge from an open pulp-cavity at nearly right angles to 

* Odontography, part ii. p. 266. f Geological Transactions, 1836, p. 349. 



154 REPORT — 1841. 

the surface of the tooth ; they form a slight curve at their origin, with the 
concavity directed towards the base of the tooth ; then proceed straight, and 
at the periphery bend upwards in the contrary direction. The diameter of 
the calcigerous tube is sj^q*'^ °^ ^^ ^'^^^ ' ^^^^ breadth of the interspace of the 
tubes is g^jjjth of an inch. The crown of the tooth is invested Avith a simple 

coat of enamel. 

This microscopic examination of the structure of the teeth, which I have 
been enabled to make by the kindness of Mr. Stutehbury, satisfactorily esta- 
blishes the distinction between the Saurian of the Bristol conglomerate and 
the reptiles of the later member of the new red sandstone system in War- 
wickshire, which I have described under the name of Lubyrinthodon. 

Palceosaurus, Riley and Stutehbury. — In the formation which contained 
the jaw and teeth of the Thecodontosaurus, two other teeth were separately 
discovered, differing from the preceding and from each other ; the crown of 
one of these teeth measuring 9 lines in length and 5 lines in breadth. It is 
compressed, pointed, with opposite trenchant and serrated margins ; but its 
breadth as compared with its length is so much greater than in the Thecodonto- 
saurus, that Dr. Riley and Mr. Stutehbury have founded upon it the gemxsPa- 
lceosaurus,and distinguish it by the specific name oiplatyodon, from the second 
tooth, which they refer to the same genus under the name of Palceosaurus 
cylindrodon. The portion of the tooth of the Palceosaurus cylindrodon which 
has been preserved, shows that the crown is sub-compressed and traversed by 
two opposite finely-serrated ridges, as in the Thecodontosaurus and Rho- 
palodon ; its length is 5 lines, its breadth at the base 2 lines. 

The vertebrae associated with these teeth are biconcave, with the middle 
of the body more constricted, and terminal articular cavities rather deeper 
than in TeleosaWrus ; but they are chiefly remarkable for the depth of the 
spinal canal at the middle of each vertebra, where it sinks into the substance 
of the centrum ; thus the canal is wider, vertically, at the middle than at the 
two ends of the vertebra : an analogous structure, but less marked, obtains in 
the dorsal vertebrae of the Rhynchosaurus from the new red sandstone of 
Shropshire. 

Besides deviating from existing lizards in the thecodont dentition and bi- 
concave vertebrae, the ancient Saurians of the Magnesian conglomerate also 
differed in having some of their ribs articulated by a head and tubercle to 
two surfaces of the vertebra, as at the anterior part of the chest in Crocodiles 
and Dinosaurs. The shaft of the rib was traversed, as in the Ichthyosaur 
and Rhynchosaur, by a deep longitudinal groove. Some fragmentary bones 
indicate obscurely that the pectoral arch deviated from the Crocodilian and 
approached the Lacertian or Enaliosaurian type in the presence of a clavicle 
and in the breadth and complicated form of the coracoid. The humerus ap- 
pears to have been little more than half the length of the femur, and to have 
been, like that of the Rhynchosaurus, unusually expanded at the two extre- 
mities. The femur is thus described by the discoverers of the present the- 
codont reptiles : — 

" Two femurs, in a tolerable state of perfection, have fortunately been 
found ; one, of the right side, exhibiting nearly the whole of the bone, the 
inferior condyles only wanting ; the other is the left, and exhibits the con- 
dyles, but is very imperfect at the superior extremity. The first mentioned 
measures 10 inches in length ; from the head to the middle of the trochanter 
3 inches j^ths ; from the trochanter to the inferior condyle 5 inches /^ths. 
In the left femur the transverse diameter of the condyles is 2 inches y%ths ; 
the centre of the cylinder 1 inch. They are curved in two directions upon 



ON BRITISH FOSSIL. REPTILES. 155 

the axis, giving them somewhat a twisted form, or the shape of a long/an- 
tero-posteriorly. The trochanter is well preserved, wedge-sliaped, and of 
considerable size, as may be seen by reference to the figures. The articular 
head is flattened at the space between the trochanter, and the articular ex- 
tremity is more curved than any other part of the bone : the centre is nearly 
round, but a slight elevation or ridge exists on its posterior surface, in the 
situation of the linea aspera of the human femur. The condyles are flat- 
tened, the outer one being the larger ; there is a deep depression between 
them posteriorly, and a very slight one anteriorly. 

" On an attentive comparison of these femurs with those of the Crocodile 
and Megalosaurus, we again recognise a resemblauce. A comparison with 
the femurs of the Monitors evidently shows that our animal cannot have be- 
longed to that family. The femurs of the Monitor are much less curved, 
being nearly straight, and the trochanter is much nearer the articular ex- 
tremity ; characters sufficiently showing a wide diff"erence between them." 

The tibia, fibula, and metatarsal bones manifest, like the femur, the fitness 
of the thecodont Saurians for progression on land. The ungual phalanges 
are sub-compressed ; curved downwards, pointed, and impressed on each 
side with the usual curved canal. 

The general conclusions which may be drawn from the knowledge at pi^e- 
sent possessed of the osteology of the Thecodontosauriis and PalcEosaurus, 
the antiquity of which the discoverers of these genera regard as being greater 
than that of any other vertebrated animals, excepting fishes, are, that in their 
thecodont type of dentition, biconcave vertebrae, double-jointed ribs, and pro- 
portionate size of the bones of the extremities, they are nearly allied to the 
Teleosaurus ; but that they combine a Lacertian form of tooth, and structure 
of the pectoral and probably pelvic arch with these Crocodilian cliaracters, 
having distinctive modifications, as the moniliform spinal canal, in which, 
however, the almost contemporary Rhynchosaur participates. It would be 
interesting to ascertain whether the caudal vertebrae are characterized, as in 
the Thuringian Protorosaur, by double diverging spinous processes*. 

Cludyodon, nob. — In the new red sandstone (Keuper?) of Warwick and 
Leamington, there occur detached, pointed, trenchant, recurved teeth, the 
crowns of which are sometimes 1 inch 4 lines in length, and 5 lines across the 
base : they have been found in the same quarries as those containing the re- 
mains of the LabyrinthodoH. In their compressed form, anterior and posterior 
serrated edges, sharp points, and microscopic structure, these teeth agree with 
those of the Saurian reptiles of the Bristol conglomerate. In their breadth, as 
compared with their length and thickness, they are intermediate between the 
Thecodontosauriis and the Palccosaiiriis platyodon ; but they are larger, with 
longer and more recurved crowns, and thus more nearly approach the form 
characteristic of the teeth of the Megalosaurus\. From these teeth, however, 
they differ in their greater degree of compression, and in a slight contraction 
at the base of the crown ; I therefore indicate the genus, of which, as yet, only 
the teeth are known, by the name of Cladyodon, and the species from the 
Warwickshire sandstones by the name of Cladyodon Lloydii, in testimony 
of the friendly aid of Dr. Lloyd of Leamington, to whose zealous co-opera- 
tion I owe the materials for the description of the teeth of the present genus, 
and the still more remarkable ones of the British species of Labyrinthodon, 
with which tiie teeth of the Cludyodon are associated. 

* This structure I have ascertained in the original specimen described by Spener, now 
preserved in the Iliiiiterian Museum. 

t One of the teeth of the Cladyodon is figured in the Memoir of Messrs. Murchison and 
Strickland on the Warwick Sandstones, Geol. Trans., second series, vol. v. pi. xxviii. fig. 6. 



156 REPORT — 1S41. 

Order PTEROSAURIA. 

The term Ornithocephalus, originally imposed by Soemmering on the genus 
Pterodactjjlus, Cuv,, which is the typo of the present extinct order of reptiles, 
would be much more applicable to the RJti/nchosaurus ; for although a more 
striking approach to the class of birds is made by the modification of the 
pectoral extremity which endowed the Pterodactyle with the power of flight, 
it is precisely in the structure of the cranium that it adheres most closely to 
the ordinary Saurian type of structure. 

The genus Pterodactylus was ranked among the swimming-birds by Blu- 
menbach, with the clieiropterous Mammalia (Bats) by Hermann and Soem- 
mering, and has been proved to belong to the order of Reptiles by Cuvier, 
The Pterodactylus longirostris, from the lithographic slate of Pappenheim, 
was the earliest known species ; the Pter, hrevirostris, Pter. medius, and Pter. 
grandisy were next established, and subsequently the British species Pter. ma- 
cronyx was determined by Dr. Buckland, from remains discovei'ed in the lias 
of Lyme Regis, and which, before they came under the discriminative glance 
of the Oxford Professor, had passed as the bones of birds. 

Of this species Dr. Buckland describes the principal bones of the extremi- 
ties, and several vertebrae ; the cranium has not yet been discovered. The 
valuable subject of th^ Professor's memoir is deposited in the British Mu- 
seum ; the Memoir is contained in the thii'd volume of the second series of 
the Transactions of the Geological Society, and an accurate figure of the 
specimen is given, of the size of nature, at plate xxvii.* 

A second stratum, in which the remains of Pterodactyles have been de- 
tected by Dr. Buckland, is the oolite slate of Stonesfield. Some fine speci- 
mens of the lohg bones of the extremities of Pterodactyles from that locality, 
in the collection of John Hunter, were referred by that celebrated anatomist 
to the class of birds. 

Sauria IncertjE Sedis. 

Pohjptychodon. — A large species of Saurian is indicated by thick conical 
teeth, having the general character of those of the Crocodile, but distin- 
guished by numerous, closely-set, longitudinal ridges, M'hich are continued, of 
nearly equal length, to within 2 lines of the apex of the crown. These teeth 
have been described and figured in my ' Odontography' under the name of 
Pohjptycliodon. In their size and general form these Saurian teeth resemble 
those of the great sauroid fish, Hypsodon, Ag., but may be distinguished by 
the solidity of the crown, and the conformity of the structure of the dentine 
with tliat of the Crocodiles ; also by the ridges on the exterior of the crown 
of the Hypsodon's teeth being alternately long and short, and terminating 
abruptly at difierent but commonly greater distances from the apex than in 
PolyjJtychodon, the interspaces between the longer ridges widening as they 
approach the apex. The tooth of the Pohjptychodon is slightly and regu- 
larly curved, and invested Avith a moderately thick layer of enamel, of which 
substance the ridges are composed, the surface of the outermost layer of den- 
tine being smooth. A tooth of this reptile from the lower greensaud 
(Kentish-rag quarries) near Maidstone, in the collection of Mr. Benstead of 
that townf, has a crown 3 inches long, and 1 inch 4 lines across the base. 
The compact dentine is resolved by decomposition into a series of super- 
imposed thin hollow cones, and the short and wide conical pulp-cavity is con- 

* See also the interesting cliaptw on " Flying Saurians'' in the 'Bridgewater Treatise,' 
vol. i. 1). 221. 

t Presented by that gentleman, since the reading of this Report, to the Museum of the 
Royal College of Surgeons. 



ON BRITISH FOSSIL REPTILES. 157 

fined to the base or fang. The cavity of the tooth in Hypsodon would ap- 
pear to have been much larger, as it is in many predatory iishes, in which the 
teeth are more rapidly shed and renewed than in Crocodilian reptiles. 

The teeth of Poli/ptychodon differ from those supposed to have belonged 
to Poiliilopleuron, in the ridges of the crown being more numerous and close 
set, and in the transverse section being nearly circular instead of being ellip- 
tical : from the teeth of Pliosaurus those of Polyptychodon differ in being 
round and not three-sided, and in having longitudinal ridges over the whole 
surface of the crown ; and from the teeth of 3Iosasaurus they differ in being 
ridged and not smooth. 

Gigantic Fossil Saurian from the Lower Greensand at Hytlie. 

Under this head I have to notice some remains of a Saurian of marine 
habits, but most probably of the Crocodilian order, as gigantic as the Ceiio- 
saurus or Polyptychodon, but, in the absence of dental and vertebral charac- 
ters, not referable to any known genus. These remains were discovered by 
H. B. Mackeson, Esq. of Hythe, in the greensand quarries near that town, 
and include portions of the iliac, ischial and pubic bones, a large proportion 
of the shaft of a femur, parts of a tibia and fibula, and several metatarsal 
bones. In consequence of the absence of vertebras and teeth, the present ob- 
servations will be limited to indicating the characters by which these remains 
differ from previously known extinct genera of Saurians. In the first place, 
as the femur and other long bones have no medullary cavities, but a central 
structure composed of coarse cancelli, it is evident that the animal of which 
they formed part was of marine habits ; but the best- preserved bone being a 
femur, this circumstance, independently of the size and shape of the metatar- 
sals, at once negatives the idea that these remains belonged to the Cetacean 
order, whilst the form and proportions of the metatarsals equally forbid their 
reference to any other Mammalian genus. 

Femur. — The portions of this bone secured by Mr. Mackeson include 
about the two distal thirds, excepting the articular extremity ; its length is 

2 feet 4 inches ; its circumference in the middle, or smallest part of the shaft, 
is 15 inchec 6 lines, and at the broken distal end, 2 feet 5 inches. These 
dimensions prove that the animal was equal to the most gigantic described 
Iguanodon*. If the supposition of the proportion of the femur which has 
been preserved be right, this bone differs from that of the Iguanodon, not 
only in the want of a medullary cavity, but also in the absence of the compressed 
process which projects from the inner side of the middle of the shaft. The 
bone also expands more gradually than in the femur of the Iguanodon, and 
the posterior jiart of the condyles nmst have been wider apart in conse- 
quence of the posterior inter-condyloid longitudinal excavation being longer 
and wider. 

Tibia and Fibula. — The portion of a tibia which has been preserved is 
compressed near its head, and the side next to the fibula is slightly concave. 
The longest transverse diameter is 8 inches 9 lines, and the two other trans- 
verse diameters at right angles to the preceding, give respectively 3 inches 

3 lines, and 2 inches 6 lines. The bone soon assumes a thicker form, its cir- 
cumference at about one-third from its proximal end being 16 inches G lines. 
The cancelli occupying the central portion of the bone are arranged in a suc- 
cession of layers around a point nearest tlie narrower end of tlie transverse 
section. Lower down the tibia again becomes compi*essed, and towards the 

* The length of the largest femur yet obtained of this Saurian is 4 feet 6 inches, its 
smallest circumference I foot 10 inches. 



158 REPORT— 1841. 

distal end the transverse section exhibits the form of a plate bent towards the 
fibula, and its narrowest transverse diameter is 2| inches. 

The portion of tlie fibula is 11^ inches long. In the middle it is flat on 
one side, slightly concave on another, and convex on the two remaining sides. 
It presents the same cancellous structure as the tibia, but the concentric ar- 
rangement of the layers of cells is more exact. Towards the opposite end of 
the bone the concave side becomes first flat, and is then produced into a con- 
vex wall, terminating one end of a transverse section of a compressed and 
bent thick plate of bone. 

Metatarsals. — These bones exhibit the characteristic irregularity of length 
of the Crocodilian metatarsals. Of two imbedded in the rock, and apparently 
the innermost and second, of the left hind-foot, the former or smaller measured 
1 foot in length and the latter 2 feet, having a diameter of 8 inches at its 
greater end, and of 4 inches 5 lines at its narrowest or middle part, and of 
G inches at its other extremity, Avhich was imperfect. The whole of the bone 
within the compact outer crust consisted of cells varying from a half to two- 
thirds of a line in diameter. Portions of four other detached metatarsals are 
described. 

Ilia, Ischia, Pubis, and Coracoid Bone. — These bones conform in the main 
to the Eiialiosaurian type. The remains of the ilia are flat and nearly straight, 
and they gradually but slightly widen towards one end. Of one ilium a por- 
tion, 25 inches long and 10 inches across at the broadest end, is preserved, 
and of the other a I'ragment 20 inches in length. 

The mesial extremities of the pubis and ischium are preserved in the same 
block of stone. The pubis differs from the Crocodilian type in its greater 
breadth. The portion exposed in this block is principally convex, but it be- 
comes concave towards the opposite or median margin. At its broadest part 
it is 13 inches across, and its length is 17 inches. This expanded extremity 
is rounded, and the diameter of the corresponding expanded extremity of the 
ischium, which is obliquely truncated, is 9 inches. In another block of stone 
the expanded extremity of the opposite pubis is preserved, and measures 14 
inches across and 22 inches in length. 

The bone which bears most resemblance to a coracoid is 2 feet in length 
and 17 inches in its greatest breadth, and it varies in thickness from 3 to 5 
inches. The breadth of this bone indicates the great development of the 
muscles destined for the movement of the fore-leg, whence it may be inferred 
that the anterior extremities were more powerfully and habitually used in pro- 
gressive motion than in the Teleosaurian Crocodiles. 

It will be sufficiently apparent, from the brief notice of the principal cha- 
racters of these interesting remains here given, that they cannot have be- 
longed to any of the genera of the great ambulatory terrestrial Dinosaurs ; 
and, on the other hand, the length, thickness, and form of the condyles of 
the femur, and the size and shape of the metatarsal bones equally remove the 
Enaliosaurs from the pale of comparison. 

There then remain, as claimants of the fossils in question, first, the great 
Mosasaunis of the Cretaceous formations, the locomotive extremities of 
which have not been yet discovered ; secondly, the equally gigantic Cetio- 
saurus brcvis, associated with the lyuanodon in the Wealden, and, from its 
or"-anization, more likely than the Iguanodon to be found in later marine de- 
posits ; finally, the Reptile of the Maidstone greensand, to which the name of 
Polyptychodon has been provisionally assigned from the configuration of its 
teeth. But, since the teeth of the geims Cetiosaurus are not yet determined, 
the identity of this genus with Polyptychodon is open to suspicion ; and sub- 
sequent discoveries may demonstrate that the great Saurian of the Hythe 



ON BRITISH FOSSIL REPTILES. 159 

greensand indicated by bones of the extremities, that of the Maidstone 
greensand by its teeth, and that of the Wealden formation recognized by 
its vertebrae, are all parts of the same extinct reptile. 

Genus Rysosteus, nob. 

I have been favoured by Mr. Johnson of Bristol, with the opportunity of 
examining a small anterior dorsal vertebra, (No. 177, of his interesting Col- 
lection,) half imbedded in its pyritic matrix, from the Bone-bed of Aust Pas- 
sage, near Bristol. 

Both articular ends of the body of this vertebra are concave, but deeper 
than in Teleosaurus, with a central short transverse linear impression. The 
lower part of the side of the body is raised into an obtuse longitudinal ridge, 
above which, between it and the transverse process, is a wide but not deep 
depression. The centrum slightly expands to the two extremities, which have 
a circular contour. The transverse process is broken off: its base, which is 
as deep as long, rests in a small proportion upon the centrum, but chiefly upon 
the side of the neurapophysis, the limits of which are not defined by a per- 
sistent suture. The neural arch rests upon the whole antero-posterior extent 
of the upper part of the centrum, rises nearly vertically to a height not quite 
equal to that of the centrum, then slopes abruptly inwards to support the base 
of the spine. This is nearly equal in antero-posterior extent to the centrum, 
and slightly increases in that direction by inclining over the interspace of the 
posterior oblique processes : it also slightly gains in thickness, and is termi- 
nated by a flat and rough surface, the contour of which is nearly parallel with 
that of the under surface of the centrum. The sides of the spine for two lines 
below the summit are wrinkled* or impressed by vertical or slightly oblique 
coarse grooves. The posterior oblique process is moderately long and slender ; 
its flat elliptical articular surface looks downwards and slightly outwards. The 
non-articular surfaces of the vertebra are smooth, except near the summit of 
the spine, the lateral ridges and grooves of which form the chief characteristic 
of the present vertebra. 

This vertebra, though it resembles those of a few species of Plesiosaur in 
the depth of its terminal articular surfaces, difl'ers too much in its length and 
lateral compression to be referable to that genus ; the rough and thick trun- 
cated summit of the spinous process rather indicates the species to have be- 
longed to the loricate family of Saurians. It diflPers from the vertebrae of the 
Teleosaur and other known Amphicoelian Crocodiles in the form and verti- 
cal thickness of the transverse processes, in the lateral longitudinal ridge of 
the centrum, and in the antero-posterior extent and form of the spinous pro- 
cess. It difl'ers from the vertebrae of the Labyrinthodon in the articidar ends 
being at right angles to the axis of the centrum and not oblique ; in the greater 
vertical thickness of the transverse process ; and in the spine not being sud- 
denly expanded and flattened at the summit, as in the dorsal vertebrae of the 
Labyrinthodon. 

The following are dimensions of the vertebra of Rysosteiis : — 

Lines. 

Antero-posterior extent of centrum 11 

Transverse diameter of articular end 5 

Vertical diameter of articular end 6 

Vertical diameter of entire vertebra 16 

Antero-posterior extent of spinous process .... 10 

* The name here proposed for the Saurian of the Bone-hed, from pucriis wrinkled, ocreov 
a bone, relates to this structure. 



160 REPORT — 1841. 

I have received other portions of lii/sosteus from tlie Bone-bed at West- 
bury Cliff, on the Severn, eiglit miles from Gloucester. 

Two spinous processes of fractured vertebrae are conspicuous and readily re- 
cognizable by their wrinkled surface and great antero-posterior extent; they 
agree also in size with the vertebra from Aust Passage, and seem to be evi- 
dently of the same species. 

The distal end of a Saurian humerus and a nearly entire femur are asso- 
ciated with these vertebral fragments. The humerus has an angular and 
twisted shaft, and greatly expanded articular extremities, the surface of which 
is ridged like the spinous processes, but with somewhat wider intervals. 

The femur equals the length of three vertebrse and a half; resembles that 
of the Teleosaurus in shape, but has the outer surface of the expanded ex- 
tremities wrinkled, though in a minor degree than in tlie humerus. The cor- 
respondence of the long bones in size, and in the wrinkled character of part 
of their surface with the vertebras, almost demonstrates that they belong to 
the same species of Saurian. 

Order CHELONIA. 
Family Testudinid^, Tortoises, or Land-Tortoises. 

Neiv Tied Sandstone Tortoises. — The most ancient of the evidences of Rep- 
tiles of the Chelonian order, in British formations, appear to be referable to 
Land-tortoises. The foot-prints upon the thin superimposed strata of the 
new red sandstone quarries at Corn-Cockle Muir, of which an account is given 
by Dr. Duncan in the Transactions of the lloyal Society of Edinburgh for the 
year 1828, and those subsequently discovered in the same ancient formation 
at the quarries of Craigs, two miles east of the town of Dumfries, are regarded 
by Dr. Buckland as bearing most resemblance to the foot-prints of a small 
species of tortoise*. 

Oolite Tortoises. — The impressions of horny scutes, about the size of those 
covering the carapace of a tortoise ten inches in length, occur not unfrequently 
in the oolitic slate of Stonesfield, and leave a light brown stain upon the matrix. 
These corres]5ond so closely in form and in the arrangement and distinctness 
of the concentric lines with those of existing tortoisesf, that the position which 
they originally held on the carapace may often be determined. 

Family EmydidjE, Fresh-water Tortoises. 

Emys, sp. indet. — In the museum of Prof. Bell there is a specimen of an 
Emydian Chelonite from the Eocene clay near Harwich, which differs from 
the Emys testudiniformis of Sheppey in its flatter figure. 

The carapace is elliptical, gently convex at the middle and concave at the 
sides, the margins being slightly raised. The external surface of i\\e osseous 
buckler is slightly rugous ; the length of the carapace is 11 inches ; its breadth 
at the suture between the fifth and sixth rib is 10 inches. 

The first vertebral plate is nearly flat ; the middle part of its posterior 
margin extends backwards about one line and a half. The second vertebral 
plate is of an oblong quadrangular figure, 6 lines in breadth : the third ver- 
tebral plate is six-sided and 8 lines in breadth, the two anterior sides being 
the shortest : the tenth and eleventh vertebral plates are broad. 

* "On comparing somo of tliese ini])ressions witli the tracks which I caused to be made on 
soft sand, clay, and upon nubalced pie-crust, by a living Emys and Testudo Grceca, I found 
the correspondence with the latter sufficiently close, allowing for difference of species, to ren- 
der it highly probable that the fossil footsteps were also impressed by the feet of land-tortoises." 
— Bridgewater Treatise, vol. i. p. 261. 

t The Emys centrata is, however, so denominated on account of the resemblance of its 
scutes, in their concentric striation with those of tortoises, 



ON BRITISH FOSSIL REPTILES. IGl 

The normal or rounded portion of the rib begins to project from the under 
surface of the expanded plate at two inches distance from the head of the rib ; 
but the superincumbent expanded portions and their sutures are continued as 
far as the marginal plates ; as in other full-grown Emydes. 

Emys testudiniformis, nob. 
Emys de Sheppey, Cuv. ? 

Most of the Chelonites from the Eocene clay of Sheppey belong to the ma- 
rine family* of the order, from which the present species differs in the depth 
of the bony cuirass, the convexity of the carapace, the concavity of the plas- 
tron, and the extent of ossification of both these parts. The more immediate 
affinities of the present fossil are elucidated by the comparison of the points 
of structure which it displays with the anatomical characters of the carapace 
of the Emys and Testudo. 

The specimen, on which the species Emys testudiniformis is founded, in- 
cludes a large proportion of the first, second, third, fourth, fifth and sixth, 
with a fragment of the seventh expanded vertebral ribs of the left side ; a 
small proportion of the second, third, fourth, fifth and sixth vertebral plates ; 
the hyo- and hyposternals, and part of the entosternal bones of the plastron. 

The first rib is 1 inch 10 lines, in greatest breadth ; 1 inch 5 lines broad 
at its junction with the vertebral plates, and four-fifths of the vertebral mar- 
gin is articulated with the second vertebral plate ; one-fifth part, divided by 
an angle from the preceding, joins a corresponding side of the lateral angle 
of the third vertebral plate ; in this structure it resembles both the genus 
Testudx) and some species of Emys. 

The third, fourth, fifth and sixth vertebral plates are of equal breadth as 
in Emydes ; not alternately broad and narrow as in the Testudines : they are 
likewise of uniform figure, as in most Emydes ; not variable, as in Testudines : 
the vertebral plates also resemble those of the existing Emydes, and particu- 
larly of the Box-terrapin (^Cistudo) in form. The lateral margin of each is 
bounded by two'lines, meeting at an open angle, the anterior line is only one- 
fourth part the length of the posterior one ; and this resemblance may be stated 
with confidence, since the portion of the entosternal piece preserved in the 
plastron determines the anterior part of the fossil. 

The ribs preserved in the present Chelonite differ from the corresponding 
ones of the Tortoises and resemble those of the Emydes in their regular 
breadth, and the uniform figure of the extremities articulated with the ver- 
tebral pieces ; the anterior line of the angular extremity is nearly three times 
as long as the posterior one. 

Further evidence of the relation of the present Chelonite to the freshwater 
family is given by the impressions of the epidermal scutes : those covering 
the vertebral plates {scuta vertebralia) agree with those of most Emydians 
in the very sligiit production of the angle at the middle of their lateral mar- 
gins, which is bounded by a line running parallel with the axis of the cara- 
pace, except wliere it bends out to form that small angle. 

The middle part of each side of the plastron, in the Emys testudiniformis, 
is joined to the carapace by a strong and uninterrupted bony wall, continued 
from a large proportion of the hyo- and hyposternal bones upwards to the mar- 
ginal costal pieces. The median margin of the hyo- and hyposternals are ar- 
ticulated together by a linear suture, traversing the median line of the plas- 
tron, and only broken by a slight angle formed by the right hyposternal, whicli 
is a little larger than the left. A similar inequality is not unusual in both Tor- 
toises and Emydes. The transverse suture is, of course, broken by the same 

* See Proceedings of the Geological Society, Dec. 1, 184L 
IS'il. M 



162 REPORT — 1841. 

inequality ; that portion which runs between the left hj'^o- and hyposternals 
being two or three lines in advance of the one between the I'ight hyo- and 
hyposternals. The posterior half of the broad entosternal piece is articulated 
to a semicircular emargination at the middle of the hyosternals ; so that the 
whole plastron forms one continuous plate of bone. This is relatively thicker 
than in existing Emydes, resembling in its strength that of Tortoises ; and it 
is likewise slightly concave in the middle, which structure is more common in 
Tortoises than in Emydians, save those in which the sternum is moveable ; in 
most of the other species the sternum is flat or slightly convex. 

I have shown in my paper on the Turtles of Sheppey *, that the carapace 
figured by Cuvierf was not sufliiciently perfect to decide, the affinities of the 
Chelonian to which it belonged ; if the vertebral scutes were less broad and 
angular than in marine turtles, the vertebral plates — much less variable in 
their proportions — were, on the other hand, as narrow as in turtles. But with 
reference to the plastron of the Sheppey Chelonite, figured by Parkinson I, 
and supposed by Cuvier to belong to an Emys of the same species as the ca- 
rapace above alluded to, I have been able to determine, by an examination 
of the original specimen in the museum of Prof. Bell, that it belonged to the 
marine genus Chelone and to the species lovglceps. In the fossil JEmys in 
Mr. Bowerbank's collection, the plastron being in great part preserved, esta- 
blishes its nonconformity with the marine turtles, and manifests a striking 
diff'erence from Parkinson's fossil plastron. 

The entosternal piece is impressed, as in Tortoises and Emydes, by a me- 
dian longitudinal furrow; a transverse linear impression traverses the hyoster- 
nals half an inch behind the suture of the entosternal; the second transverse 
line is not so near the first as in Tortoises, but bears the same relation to the 
transverse suture of the plastron as in most Emydes ; it does not pass straight 
across the plastron, but the right half inclines obliquely inward to a more 
posterior part of the median suture than is touched by the left half. The 
third transverse line passes straight across the plastron between the posterior 
ends of the bony lateral walls, uniting the carapace and plastron. 

In. Lines. 

The breadth of the plastron is 5 10 

The outer posterior extent of the lateral wall is .... .3 9 

The breadth of the entosternum 1 5 

The depth of the whole bony cuirass at the middle line is 4< 

In the convexity of the carapace and relative depth of the osseous box the 
Sheppey Chelonite slightly surpasses most existing species, resembling in this 
respect the JEmys ocellata and Cistudo Carolina. The plastron is also slightly 
concave, as in the male of Cistudo vulgaris : it is, however, entire at the line 
where the transverse joint of the plastron exists in the Box-tortoises; and the 
extent and firm ossification of the lateral supporting walls of the carapace for- 
bid likewise a I'eference of the fossil to those genera. The general characters 
of the present fossil, more especially the uniformity of size and breadth of the 
preserved vertebral plates and ribs, prove it to be essentially related to the 
freshwater or Emydian Tortoises. It exceeded in size, however, almost all 
known Emydians, and was almost double the dimensions of the Emydian spe- 
cies ( Cistudo Europea^ now inhabiting central Europe. It appears, like the 
Cistudines, to have approached the form of the land-tortoises, in the convexity 
of the carapace, but without possessing that division and hinge of the plastron 
which peculiarly distinguishes the box-tortoises. In the thickness and strength 

* Geological Proceedings, December 1, 1841. 
t Ossem. Foss., torn. v. part iv. pi. xv. fig. 12, 
X Organic Remains, vol. iii. pi. xviii, fig. 2. 



ON BRITISH FOSSIL REPTILES. 163 

of the bones of the buckler, especially of the sternum, we may discern an affi- 
nity to Testudo. 

Assuming that the Chelonite here described may be identical with that of 
which the carapace from Mr. Crow's collection is figured in the ' Ossemens 
Fossiles*,' the 'Emys de Sheppey' of Cuvier will be one of the ' Synonyms' of 
the present species. Mr. Gray, in his ' Synopsis Reptilium,' has given Latin 
names to all the fossil reptiles indicated or established by Cuvier, and has 
called the ' Emys de Sheppey ' ' Emys Parkinsonii,' referring as representa- 
tions of this species, not to the figure of the carapace above cited, which may 
belong to the same species as the present Emys, but to the figure of the 
plastron, copied by Cuvier from ' Parkinson's Organic Remains,' and to the 
figure of the skull in the same work, both of which most unquestionably be- 
long to the genus Chelone and not to the genus Emys. 

The ' Emys Parkinsonii ' of Mr. Gray is a synonym of my Chelone longiceps. 
Cuvier's name, — which, besides the claim of priority, is the honest result of 
labour devoted to the elucidation of its subject, — if rendered into Latin would 
be Emys toliapicus ; but as the species to which it refers may not be the one 
here described, and is not the only freshwater tortoise which the clay of 
Sheppey has yielded ; and since the characters of the present species have 
not, hitlierto, been defined nor its affinities to the land-tortoises been pointed 
out, the interests of science, it appears to me, will be best consulted by naming 
the present species Emys testudiniformis. 

The fossil here described is from the Eocene clay of Sheppey Island, and 
forms part of the collection of J. S. Bowerbank, Esq. 

Platemys Boiverbankii, nob — Another specimen from the same rich col- 
lection of Sheppey remains actually indicates a distinct species of the fresh- 
water family of Chelonia, which from its more depressed figure, its size, and 
the general form of the sternum, most probably belonged to the Platemydian 
division of that family f. 

The sternum is 13 inches in length and 10 inches in breadth ; it is 
broader before than behind, rounded in front, notched behind : the surface 
is nearly flat, slightly convex at the anterior part, and as slightly concave 
behind. 

The lateral bony wall or ala uniting the plastron to the carapace is 5 inches 
in length or antero-posterior extent, and it commences 3 inches behind the 
anterior extremity of the plastron. The episternals meet in advance of the 
entosternal, the length of the suture joining their anterior extremities, being 
7 lines : from the peripheral end of this suture to that of the suture between 
the episternal and hyosternal bones is 2 inches 6 lines : from the latter suture 
to the anterior concavity of the lateral wall is 5 lines. In a tortoise with a 
plastron 13 inches long, the length of the same suture was 1^ inch, and the 
suture between the episternal and hyosternal bones is nearer the lateral wall. 
The Emydes, especially Emys {Platemys) depressa, most resembles the fossil, 
especially in the more important character of the relative length of the lateral 
wall and suture. 

The carapace presents the same conformation and regularity of size of the 
vertebral plates and ribs as in the Emys testudiniformis ; but it is flat, even 
slightly concave along the middle tract ; and has somewhat narrower verte- 
bral plates, of which the third to the eighth may be distinguished in the fos- 
sil ; the ninth being concealed by the union of the vertebral extremities of 
the 7th pair of expanded ribs. 

* Ed. 1824, vol. V. part ii. pi. xv. fig. 12. 
t Ilydraspk, Bell and Gray. 
M 2 



1G4 REPORT — 1841. 

The vertebral plates are all smooth and flat ; their dimensions are as fol- 
lows: — In. Lines. 
Length of the fourth plate ...... 1 1 1 

Greatest breadtli . . . ' 1 3 

Length of the fifth plate 1 8 

Greatest breadth 1 3 

Length of the sixth plate 1 6 

Greatest breadth 1 3 

Length of the seventh plate 1 1 

Greatest breadth 1 3 

Length of the eighth plate 9 

Greatest breadth 1 

In the circumstance of the vertebral plates in this fossil decreasing in length 
without losing breadth, as well as in the junction of the seventh pair of ribs, 
the present fossil resembles the Sheppey carapace from Mr. Crow's collection 
figured by Cuvier ; which may, therefore, have belonged to the present spe- 
cies of Platemys. 

Platemys Bullockii, nob. — A very fine plastron of a Platemys from Shep- 
pey was obtained by the British Museum at the sale of Bullock's collection, 
which differs from the preceding in the finely punctate character of the ex- 
ternal surface of the bone, and in the narrower notches between the body of 
the plastron and the lateral alae or uniting wall. The following are dimen- 
sions of this specimen : — In. Lines. 

Length 16 6 

Extreme breadth (anterior to lateral wall) 8 

Breadth or transverse extent of lateral wall 2 6 

Antero-posterior extent of lateral wall 5 6 

Antero-posterior extent of carapace anterior to lateral wall . 5 
Antero-posterior extent of carapace posterior to lateral wall 6 

The anterior contour of the sternum is rounded ; the posterior termination 
is notched. The lateral wall extends horizontally, almost parallel with the 
plane of the sternum, and expands to join, by a wavy suture, the marginal 
plates ; six of these are preserved on each side ; their lower margins form a 
very open angle. The anterior part of the entosternum is bounded by two 
nearly straight lines, converging forwards at an angle of 65°, with the apex 
rounded off; the posterior contour of this bone is semicircular. The length 
of the entosternal is 2 inches 10 lines ; its breadth 3 inches 7 lines. 

The chief peculiarity of this plastron is the intercalation of a supernume- 
rary piece of bone between the hyosternal and hyposternal elements, on each 
side ; so that the plastron is crossed by two transverse sutures, instead of one ; 
each suture being similarly interrupted in the middle by an angular deflection 
from the right, half an inch back, to the left side. The extremities of the 
transverse sutures terminate each at the apex formed by the inner or lower 
border of the parallel marginal plates. The first or anterior of these sutures 
is distant from the anterior margin of the plastron 6 inches 5 lines : the second 
suture is distant from the same margin 8 inches 9 lines : the right half of the 
suture, which is a few lines in advance of the left, is the part from which 
these measurements are taken. 

It might be suspected that the transverse impressions of the second or third 
pairs of sternal scutes had liere been mistaken for a suture ; but due care was 
observed to avoid this error: the sternal scutes have left obvious impressions, 
which prove that they were in the same number as in the Platemydians ge- 
nerally, and quite distinct from the sutures in question. 



ON BRITISH FOSSIL REPTILES. 165 

Thus the first median scute is in the form of an ancient shield ; its posterior 
apex impressing and crossing the anterior apex of the entosternum. The pos- 
terior transverse boundary of the succeeding pair of sternal scutes crosses the 
plastron 4^ inches from its anterior margin ; that of the third pair of scutes 
crosses at 7| inches from the anterior border, and between the two transverse 
sutures ; that of the fourth pair at 10 inches distance from the anterior mar- 
gin, and about 1^ inch behind the second transverse suture ; passing straight 
across the plastron between the posterior concave margins of the lateral walls. 
The posterior boundary of the fifth pair of scutes inclines obliquely back- 
wards from the median line, as usual ; it is 3 inches behind the preceding 
transverse impression. 

It is in the interspace of these impressions that traces of the transverse su- 
ture between the hyposternals and xiphisternals are obvious, about 4 inches 
from the posterior extremity of the plastron. If these traces were not so ob- 
vious, it might be supposed that the xiphisternals were of unusual length, 
entering into the formation of the lateral wall, and extending backwards from 
the second transverse suture to the end of the plastron ; but this disproportion 
would be hardly less anomalous than the existence of the additional pair of 
bones intercalated between the hyo- and hyposternals which this present fossil 
evidently displays. 

In most of the existing large Emydes and Platemydes, the median transverse 
suture traverses the plastron a little behind the third pair of scutes, or across 
the fourth pair ; so that the second transverse suture in the fossil has the ana- 
logous position, and accordingly has most right to be regarded as the normal 
boundary between the hyo- and hyposternals. One of the most distinctive 
characters of the present extinct Platemys is, therefore, the division of each 
hyosternal bone into two, the sternum consisting of eleven instead of nine 
pieces ; if the very interesting anomaly which it displays be not an accidental 
or individual variety. 

The chief difference in regard to the sternal scutes, is the addition of two 
small ones anteriorly, one on each side of the median anterior pair in the 
fossil. 

The obtuse ridge which forms the angle between the carapace and plas- 
tron is preserved in the fossil. 

Tretosternon punctatum, nob. — In the rich collection of fossil remains be- 
longing to Sir P. Egerton, there is the posterior part of the carapace of a fine 
species of freshwater tortoise, which, by its broad and extremely flattened 
form and sculptured surface, is evidently closely allied to the genus Trionyx, 
but which, from the impressions of distinct horny scutes, is essentially related 
to the Emydian family, and is nearly allied to the genus Platemys, D. & B. 
(^Hydraspis, Bell.) : this portion of carapace contains the fifth to the twelfth 
vertebral plates inclusive, and the five posterior pairs of expanded vertebral 
ribs. The external surface of both elements of the carapace is closely pitted 
with minute irregular impressions, smaller than a pin's head, and along their 
sutural margins for the extent of two or three lines by straight and parallel 
linear impressions, at right angles or nearly so to those margins : the pin- 
head impressions are sparing or absent at these striated margins. 

The breadth of the carapace, across the fourth pair of ribs, is 13|^ inches : 
the length of the moiety of the carapace here preserved is 9 inches : the en- 
tire length would be, probably, 17 inches. The flattened ribs gradually ex- 
pand towards their distal extremity. 

The close resemblance which this species makes to the Trionyces, in the 
sculpturing of the external surface of the carapace, is very striking ; but the 
impressions of the horny scutes, and the non-continuation of a narrow tooth- 



166 REPORT — 1841. 

like portion of the rib from the distal end of the expanded part, are essential 
distinctions. 

The entire and rounded terminal margins of the truncated and expanded 
extremities of the ribs, beyond which there is not the slightest trace of pro- 
jecting tooth-lilce processes, strongly indicates that the marginal plates were 
either wanting or rudimental, as in the genus Cryptopus, 

This fossil is from the Purbeck limestone. 

In the collection of Mr, Bowerbank is preserved the left half of the plas- 
tron of the same species of freshwater tortoise, from the Purbeck limestone, 
at Swanage, equal in size and probably of the same species as the preceding, 
but with fainter impressions on the external surface. This Chelonite includes 
the hyosternal, the hyposternal, and a considerable part of the xiphisternal 
bones, but wants the extremity of this bone. It is a very remarkable and 
characteristic fossil, chiefly on account of the great extent of the lateral wall, 
which is continued outwards, in the same plane with the rest of the plastron, 
as in the Emydian subgenus Platysternon, Gray, accompanied by an unusual 
width of the notches, anterior and posterior to this wall, for the emergence of 
the fore and hind-feet. The length of this fossil, taken along the median su- 
ture, is 13 inches; the breadth of the sternum along the median transverse 
suture must have exceeded 12 inches. The antero-posterior extent of the 
contracted part of the lateral wall is 7 inches ; that of its expanded outermost 
part 9 inches ; the antero-posterior diameter of the hyposternal bone 4 inches 
4 lines ; extent of transverse suture between this and the xiphisternal 3 inches. 
The outer and anterior angle of the xiphisternal has a shallow angular notch 
which receives a corresponding process of the hyposternal : the median mar- 
gin of the hyposternal has a semicircular piece cut out of it just where it joins 
the hyosternal : the bone gradually narrows off to the edge of this emargi- 
nation, which is exposed, by a careful removal of the matrix, without any 
trace of fracture of the bone. If it be, as it seems, a natural structure, then 
the centre of the sternum must have presented an elliptical vacuity, closed by 
membrane or cartilage of nearly two inches diameter, situated immediately 
behind the transverse suture uniting the hyo- and hyposternals. Such an ap- 
proximation to the Trionyces and Chelones presented by an extinct species, 
which from the extensive lateral union by a continuous bony plate of the side 
of the plastron with the carapace, and from the complete ossification of the 
latter is essentially an Emydian species, forms a very interesting transitional 
modification, especially if it be combined, as there seems good reason to be- 
lieve, with the sculptured surface of a remarkably flattened carapace, such as 
the Chelonite, in Sir P. Egerton's collection, from the same stratum and loca- 
lity presents. 

The sternum, like the carapace above mentioned, is impressed by the mar- 
gins of distinct scutes. 

The transverse line bounding the second sternal scute has the same rela- 
tive position as in the Testudo Schweigeri and Platemys planiceps. The two 
succeeding sternal scutes have a more equal antero-posterior extent than in 
those species. The impression commences at the median line, nearly an inch 
in advance of the transverse suture and three inches behind the second trans- 
verse scute, and describes a slight curve which is convex towards the anterior 
part of the plastron. The third scutal line commences from the middle of the 
median emargination, and instead of running parallel with the preceding line, 
as in the Tortoises and ordinary Emydes which I have examined, it inclines 
backwards as it passes outwards, and terminates at the middle of the posterior 
lateral emargination. The fifth scutal line is oblique, as in the Emydians 
generally, and here therefore runs parallel with the fourth line at a distance 



ON BRITISH FOSSIL REPTILES. 16? 

of three inches and a half from it. The line bounding the lower part of the 
marginal scutes, which in Tortoises is either parallel with or a little above the 
suture uniting the lateral wall of the plastron with the marginal plates, here 
intersects the marginal wall of the plastron at a distance of from two-thirds 
of an inch to one inch and a half from that margin : impressions of four of 
the marginal scutes may thus be traced upon this part of the sternum, a struc- 
ture in which the present fossil differs most remarkably from all known ex- 
isting Tortoises. This difference it is the more necessary to bear in mind, 
since, in the antero-posterior extent as well as the transverse extent of the 
lateral wall of the sternum, and in the form and extent of the emarginations 
which bound the anterior and posterior pai't of this wall, the present fossil 
exhibits a closer resemblance with the Land-tortoises than with the ordinary 
Emydes. But the external surface of the plastron, instead of being slightly 
concave, as in most tortoises, is slightly convex ; and where the plastron is 
convex externally in existing tortoises, namely, at the outer margin of the 
lateral wall, the fossil exhibits a slight concavity. In short, the character of 
the surface is such as Avould lead one having in his mind the plastron of a 
Tortoise as the ground of comparison, to suppose, at the first sight of the fossil, 
that he was looking on the inner side of the plastron ; but the distinct and 
well-marked impressions of the epidermal scutes proves that it is actually the 
outer surface of the plastron which is here exposed. The anterior margin of 
the plastron is truncated, as in most Platemydians. 

The osseous basis of the present plastron is half an inch in thickness ; the 
structure of the bone is compact at the surface, including a coarsely spongy 
diploe, as in the Chelonians generally. 

Portions of ribs of the Tretosternon pu7ictatum*, which from their specific 
punctation and sculpturing of the outer surface have been referred to the 
genus Trionyx, have been discovered by Dr. Mantell in the Wealden of Til- 
gate. 

Amongst recent Emydians an approach to the Trionyces is made by the 
subgenus Cryptopus {Emyda of Gray), inasmuch as the marginal plates, espe- 
cially of the posterior free margin of the carapace, exist in a rudimental or 
abortive state, as small granulated ossicles, suspended in the integument cover- 
ing that border. 

The subgenus Chelydra manifests its affinity to Trionyx by another modi- 
fication of its osseous structure, viz. the absence of the lateral osseous walls, 
or alaj joining the plastron to the carapace, which are united only by flexible 
cartilage, throughout life. 

No known existing species of Emydian has a free unossified central space 
in the sternum in the full-grown state; but this is an immature character 
common to all Chelonians, and is persistent in marine Turtles and Trionyces. 

In the present highly interesting extinct genus, Tretosternon, it would ap- 
pear that the absence of marginal plates, and a cartilaginous union of the 
plastron with the carapace, Avere associated likewise with a small vacuity in the 
middle of the sternum of the mature animal. The evidently feebly-developed 
scutes, and the sculpturing of the external surface of the flattened carapace, 
complete the last step in the transition from the Elodite to the Potamite fami- 
lies of Chelonians in the system of MM. Dumeril and Bibron. 

Platemys Mantelli, Emys de Sussex, Cuv., Emys Mantelli, Gray The 

fossils discovered by Dr. Mantell in the Wealden strata of Tilgate Forest, and 
the resemblance of which to the flat species of Emydian discovered by M. 
Hugi in the Jura limestone at Soleure has been pointed out by Cuvier, are 
referable to the Pleuroderal section of the Emydian family, as arranged by 
* Illustrations of the Geology of Sussex, 4to, pi. vi. figs. 1, 3 & 5. 



168 REPORT — 1841. 

Messrs. Dumeril and Bibron*, and, in that section, to the genus Platemys : 
not enough of the skeleton of any individual has yet been obtained to afford 
a foundation for a specific character. 

Large Emydian from the Kimmej-idge Clay. — In the museum of Sir P. 
Grey Egerton is preserved the pubic bone of a large Emydian tortoise, ob- 
tained from Heddington Pits. The bone measures 4^ inches in length, and 
2 inches 10 lines in the breadth of the symphysial plate. As its specific de- 
viations, particularly in regard to the length of the sternal process, from the 
pubis of ordinary Emydians are well marked, it may probably belong to a 
species of Platemys. 

Footsteps of Emydians in New Red Sandsto7ie. — Among the numerous 
footsteps of Reptiles impressed upon the sandstone of Stourton Quarries, 
Cheshire, those of an Emydian Tortoise of moderate size are not uncommon. 

Genus Trionyx. 

Certain British fossils from the secondary formations, referred to Trionyx, 
have been proved to belong either to another family of Chelonians, or to a di- 
stinct class of animals. We learn from Dr. Buckland, that the supposed Tri- 
onyx from the new red sandstone at Caithness (Caithness slate), has been pro- 
nounced by M. Agassiz to be part of a fish : it is referable to the ganoid genus 
Coccosteus. 

I have as yet seen no Chelonite from the Wealden freshwater formations 
that can be confidently affirmed to belong to Trionyx. The specimen de- 
scribed and figured in the ' Illustrations of the Geology of Sussex,' 4to, p. 60, 
pi. vi. fig. 8, is the dermal scute of the Crocodilian genus Goniopholis, as Dr. 
Mantell himself has subsequently recognized : the other portions (pi. vi. figs. 
1, 3, 5) belong, as already observed, to the Tretosternon punctatum, a species 
which, like the Goniopholis, is common to the Wealden of Tilgate and the 
Purbeck limestone. 

Femur from lias at Linksjield. — I have been favoured by Mr. Robertson 
of Elgin, with the examination of a Chelonian femur, 4f inches in length, 
from a stratum at Linksfield, in which remains of Plesiosaurus and Hybodus 
occur ; and this femur, though not identical in form with that of any Trio- 
nyx with which I could compare it, yet resembles the modifications of the bone 
in that genus more closely than in Tortoises, Emydians or Turtles. 

Although some of the turtles of the Eocene period, as the Chelone lotigi- 
ceps, present such modifications of the jaws as seem to have adapted them to 
habits and food analogous to those of the Trionyx, yet evidences of this 
genus, to which the destruction of the eggs and young of Crocodiles is more 
particularly assigned in the Nile and Ganges, are not wanting in certain lo- 
calities where the London clay appears to have been deposited under circum- 
stances analogous to those at the termination of equally gigantic rivers. 

Unequivocal portions of a true Trionyx have been obtained from the 
Eocene clay at Sheppey, and at Bracklesham : they are also associated, as in 
the Paris basin, with remains of Anoplotherium and Palceotherium in the 
Eocene lacustrine deposits of the quarries at Benstead in the Isle of Wight. 

Family Chelonidje, Thalassianf family, or Tui'tles. 
Genus Chelone. 
Chelone planiceps, nob. — The oldest British geological formation from which 

* Erpetologie, 8vo, 1835, torn. ii. pp. 1/2, 372. 

t "Cheloniens ThaJassites," Dumeril and Bibron, /. c, p. 506. The unfortunate similarity 
of tlie generic name of the maiine Chelonians, viz. Chelone, with the name of the order, Che- 
Ionia, renders the term ' thalassian' convenient, in allusion to the peculiarities of the marine 
species or ' Turtles.' 



ON BRITISH FOSSIL REPTILES. 169 

fossil remains, clearly referable to the marine genus Chelone, have hitherto 
been found, is the Portland sandstone. 

Prof. Buckland possesses portions of the carapace and a beautiful specimen 
of the skull of a Chelonian from the Portland sandstone, which, in the large 
size of the orbits, the breadth but otherwise small size of the external nostril, 
the extent of the osseous plate covering the temporal fossae, and formed prin- 
cipally by the expanded posterior frontal and parietal bones, presents une- 
quivocal characters of a marine species. It differs, however, from all other 
known recent and most extinct Turtles, in having the cranium more depressed, 
the nasal bones divided by a distinct transverse suture from the pre-frontals, 
and by some otlier minor differences, in which an affinity to the Platemydian 
family may be traced. The length of this cranium is 4? inches 4 lines, its 
greatest breadth 4 inches. The chief modification of external form is the deep 
emargination of the lower border of the cranium, between the malar and tym- 
panic bones ; a character by which the present species approaches Emys and 
Testudo. The Chelone longiceps of the Eocene tertiary formations makes a 
similar but less marked approach to Emys ; and the present Turtle also re- 
sembles Chel. longiceps* in the form of the mastoid bone, which, instead of 
forming a thick convexity behind the wide tympanic cavity, forms a smooth 
and slightly concave, moderately broad, semicircular plate of bone. The 
muzzle is, however, as short in the Turtle of the Portland stone as in ordinary 
species of Chelone ; the distance, for example, from the anterior part of the 
orbit to the end of the muzzle, is only 11 lines. The median frontal sends a 
narrow pointed process forwards between the pre-frontals, as far as the suture 
which divides them from the nasal bones. The breadth of the interorbital 
space is relatively less than in recent Turtles, or than in the Chelone longi- 
ceps : it measures 8 lines. 

The median frontal enters into the formation of the upper part of the or- 
bit, in a greater proportion than in Chel. mydas : in the Chel. imbricata it is 
excluded by the imion of the post-frontal and pre-frontal bones. The outer 
surface of the skull is rather undulated, marked with fine strite and punctures, 
but not rugous, as in Chel. breviceps\; the nasal bones are convex, and 
impressed with larger pits. The upper boundary of the nasal aperture is 
straight, the lateral ones curve to a point below : the breadth of this aperture 
is 7 lines; that of the orbit is 13 lines. 

The nasal process of the superior maxillary is characterised by a slightly 
raised rough portion. 

The lower jaw closely conforms to the ordinary Thalassian type ; the sym- 
physis is convex, oblique, and as short as usual ; there is no approximation 
to the peculiar condition of this part in the Harwich Turtle ( Chel. plani- 
me?itu)nX). 

The suture between the supra-angular and dentary piece does not make 
so long and sharp an angle forwards, as in the Chelones mydas and Caretta ; 
the coronoid process is rather higher, and the dentary piece sends out a ridge 
which seems to have bounded the insertion of the temporal muscle below. 

Thus the present cranium offers ample proof of its specific distinction from 
that of any previously described Chelone ; and, while it has all the essential 
characters of that marine genus, exhibits some points of resemblance to the 
Emydians, as in the minor breadth of the interorbital space, the deep con- 
cavity of the lower border of the skull behind the orbit, and in the form of 
the mastoid bone. The separate nasal bone, which is the most interesting 

* See Proceedings of the Geological Society, December 1st, 1841. 
t Ibid. X Ibid. 



170 REPOKT— 1841. 

structure in the present skull, though hitherto unknown in the genus Chelone, 
has been met with in the Platemydian subgenus, Chelodina, the cranium of 
which, in other respects, closely conforms to the ordinary Emydian type, and 
has not the temporal fossas protected by bone, as in tW ' Emys {Podocnemis) 
expansa*. 

Chelone obovata, nob. — The most compli 3 and beau*'*"" I specimen of a 
fossil turtle, from secondary strata, that I liav&'j <^ set one from the 

estuary limestone formation of the Isle of Purbeck, in 'ihe CTolTection of Chan- 
ning Pearce, Esq. of Bradford, Wiltshire. 

This species differs from the Chelone Benstedi of the chalk, from the Gla- 
ris Turtle, and from all the well-determined Eocene species in the form of 
the carapace, which, although obtusely pointed behind, begins to contract to 
that extremity only at its posterior third part ; it gradually widens through 
the two anterior thirds of its extent, and is broadest at the junction of the 
fifth and sixth ribs ; the contour being obversely ovate, or with the broader 
end turned downwards. This modification of form arises, not from the supe- 
rior length of the fifth and sixth pairs of ribs, but f;'om the breadth of their 
sternal appendages, called marginal plates. The internal surface of the cara- 
pace is exposed to view, and is shallower than in any other Chelone ; resem- 
bling in this character the Trionyx and Tretosternon ; the margins of the 
carapace are slightly bent upwards, as in some Emydes. 

The first vertebral plate is shorter antero-posteriorly, and less deeply emar- 
ginate anteriorly than in the Maestricht Chelone f, and the first pair of ex- 
jjanded ribs is narrower. This well-marked difference fortunately occurs in 
the only parts in which a comparison could be established with the Tui'tles 
from a stratum so nearly contemporaneous with the Purbeck beds. The first 
rib is straight, and rather narrower in proportion than in the Eocene Turtles ; 
in Chelone mydas this rib is the broadest of the series. It very gradually con- 
tracts into its dentiform extremity, which on the left side appears to have been 
separated by a narrow membranous space from the anterior marginal plates, 
but not on the right side. The second rib is broader in proportion to the 
first than in any other species of Chelone, recent or extinct ; more so even 
than in the Trionyx, in which the first rib is narrower than the second. The 
third and fourth ribs are the broadest. 

In. Lin. 
The length of the expanded part of the fourth rib is . 3 
The breadth of the expanded part of the fourth rib . 1 5 
The length of the dentiform extremity 10 

The rest gradually diminish in length and breadth. They are all as flat 
upon the under surface as in Chelone mydas, presenting a great contrast to 
the Harwich species, Chel. planimentum, in this respect. 

The median row of vertebral plates, after the first, are as narrow as in most 
Chelones, and appear, as far as their form can be traced from an inside view, 
to resemble those of the Chel. mydas and Chel. longiceps, but to have been 
narrower than in the extinct Eocene Turtles : the length of the fourth ver- 
tebral plate in the Chel. obovata, for example, is 1 inch 3 lines, its greatest 
breadth is 6 lines. The eleventh six-sided plate, which resembles a triangle, 
with truncated angles, and is wedged between the last pair of ribs, is here 
divided by a transverse suture into two nearly equal parts. The twelfth plate 

* The different proportions in which the cranial bones, especially the post-frontals, enter 
into the formation of the bony covering of the temporal fossa; in the Emys expaiisa, serve to 
distinguish the skull of a Chelone from that of this exceptional example of an Emydian with 
the temporal fossae covered by bone. 

t Cuv. Ossem. Foss,, tom. v. pt. 2. pi. xiv. Tortues, fig. 1 and 2. 



ON BRITISH FOSSIL REPTILES. ' l7l 

is nearly twice as broad as long, and has convex lateral margins : the thir- 
teenth vertebral plate, or the last of the marginal plates, is relatively broader 
than in existing turtles, and has its posterior margin more feebly emargi- 
nate. The marginal p! tes differ in the superior expanse of those attached to 
the fifth, sixth and sevt.ith ribs. That to which the eighth rib is attached 
corresponds with +.he tenth in th" Chel. mydas, and the eleventh projects in 
an angular form Jie i '-^rspace between the dentiform extremity of the 

eighth rib and thi. n. elfti. t^ertebral plate. The thirteenth marginal plate sends 
a similar process between the seventh and eighth ribs : the exterior margins 
of all the marginal plates are straight, and the carapace is bounded by an 
unbroken contour. The diameter of the marginal plate attached to the fifth 
rib, parallel with the axis of the carapace, is 1 inch 6 lines ; the diameter 
transverse to the carapace is 6 lines : 

In. Lin. 

The length of the carapace 109 

The breadth of the carapace 9 6 

A considerable proportion of the plastron of the same individual is pre- 
served, together with part of the bones of the hinder extremities, and both afford 
essential characters of the genus Chelone. The plastron of the Chelone obo- 
vata resembles that of the Eocene Turtles in the greater extent of ossification, 
and especially in the greater breadth of the xiphisternals, as compared with the 
recent species ; but it differs from all other known species of Chelone in the 
greater depth of the notches at the anterior part of the hyosternals and at 
the posterior part of the hyposternals, which notches correspond with those 
that in the more fully ossified plastrons of Emijdes give passage to the four 
locomotive extremities. The essential condition, however, of the plastron 
of the marine turtles is preserved, first, in the defective ossification of the 
lateral margins of the plastron between the hyo- and hyposternals, which are 
not co-extended and united to form a lateral wall of support to the carapace, 
as in the Emydes ; and, secondly, in the form, and union by gomphosis, of the 
xiphisternals with the hyposternals : what proportion of the central part of 
the plastron continued unossified, the condition of the specimen does not allow 
of determining. There is evidence of the concavity of the sternum along 
the middle of the under surface, as in most Chelones. 

The hyosternal is chiefly remarkable for the sudden expansion of the ex- 
ternal radiated process, which occasions a notch at its posterior part, at the 
lateral unossified interspace between the hyo- and hyposternal bones, almost 
as deep as that which is anterior to the radiated process. The hyposternal 
bone presents likewise a similar modification of form. By this peculiarity of 
form the present species might be known by a single detached hyosternal or 
hyposternal bone. The tooth-like process of the hyosternal, which is im- 
planted in the xiphisternal, is received into a notch, the inner boundary of 
which is much deeper than the outer. 

The breadth of both the' xiphisternals, taken across the termination of this 
notch, is 3 inches : they are separated by an angular fissure for the extent of 
an inch at their posterior interspace, but their median dentated margins meet 
in the rest of their extent, which is about one inch and a half. 

Tlie breadth of sternum, across the hyposternal bones, is 8 inches ; the least 
antero-posterior extent of the conjoined hyo- and hyposternals is 4^ inches. 

In this admeasurement, as compared with the transverse extent o? the same 
bones, the Chelone ohovata differs in a marked degree from the Chel. lougiceps 
of Slieppey, and indeed approaches nearer to the existing species of Chelone 
than do the Eocene Turtles. The adherence to the thalassian type is like- 
wise well exhibited in the present fossil by the forms and proportions of the 



172 REPORT — 1841. 

principal bones of the hind-extremities or paddles, which are much shorter as 
compared with the fore-paddles and the body generally, in the marine than in 
any of the freshwater or land Chelonia. The length of the femur is 1 inch 
9 lines ; that of the tibia 1 inch 7 lines. The articular extremities are too 
imperfect to allow of a comparison of the forms of these bones with the cor- 
responding ones of existing species. 

Since the carapace of the Chelone obovata approaches, in those modifications 
by which it differs from other turtles, to the Emydian type, it is not impro- 
bable that the skull of the Chelonian, above described, from the contiguous 
subjacent stratum of Portland stone, which offers analogous approximations 
to the Emydian group, may belong to the same species. 

fVealden Chelone, sp. indeterm. — Portions of the carapace and plastron, 
and bones of the extremities of a large species of marine turtle, some of 
them indicating individuals with a carapace nearly three feet in length, have 
been discovered by Dr. Mantell in the Wealden strata of Tilgate Forest, and 
are figured in his valuable ' Illustrations of the Geology of Sussex.' 

No specific characters are deduced from these fossils, and the nature of the 
specimens seems not to have allowed the approximation to be carried closer 
than to the marine genus Chelone. With regard to one of the specimens, 
(pi. vi. fig. 2.) however, Mr. Clift's authority is quoted for its resemblance 
with the corresponding part of Chelone itnbricata, and Dr. Mantell acknow- 
ledges that " as Cuvier had referred the turtles of Melsbroeck to the Emydes, 
we at first entertained doubts whether our appropriation of this specimen to 
the Chelonice were correct. Mr. Clift's remark, however, tends to confirm the 
opinion that it belongs to a marine turtle," loc. cit., p. 62. 

After a careful comparison of the specimens in the Mantellian Collection* in 
the British Museum, I have come to the conclusion that the Wealden species 
differs from Chelone imbricata, Ch. carmata, and other known species in as 
great a degree as do many of the other extinct Chelones, in regard to the 
greater extent of the ossification of the costal interspaces and of the sternum. 

In the convexity of the under side of the vertebral ribs ; and in the modi- 
fications of the form of the episternal, hyosternal and hyposternal bones the 
Wealden species offers the nearest resemblance to the Chelone planimentum 
of the Harwich Eocene clay. It is to be regretted that this relationship can- 
not be more decisively tested by a comparison of the skulls, and especially of 
the lower jaw of the two species : l)ut these parts of the skeleton appear not to 
have been as yet discovered in the Wealden. 

Chelone pulchriceps, nob. — The cranial anatomy of a fossil turtle from the 
superincumbent beds of lower greensand differs from that of other known 
species, but presents the nearest resemblance to that of the turtle from the 
Portland stone. 

A small cranium of the present species of Chelone, from the greensand 
near Barnwell, Cambridge, in the museum of the Rev. Thomas Image of 
Whepstead, in the same county, is depressed, and likewise has the nasal bones 
marked off by a suture from the anterior frontals, but in a different manner 
from that in the skull of the Portland turtle. The characters of the genus 
Chelone are clearly expressed by the extensive roof of bone overarching the 
temporal fossae, and by as large a proportion of this roof being formed by the 
post-frontals as in existing Chelones. The orbits are also large, and their 
superior interspace is broad. 

The median frontals form a small proportion of the upper border of the or- 

* No. 2338, " Sternal plate of a marine turtle," MS. Catalogue of Mantellian Museum, 
now in the British Museum, is unquestionably the left hyposternal, and part of the lateral 
wall, supporting the carapace of a Tortoise or Emys. 



ON BRITISH FOSSIL REPTILES. 173 

bits ; the anterior extremities of the median frontals, instead of converging to 
a point, are extended forwards, between the anterior frontals, in a broader 
proportion than in the Portland Turtle, and are obliquely truncated : it is only 
in the genus Chelys among existing Chelonians, that the anterior frontals are 
thus separated from each other ; but in the Chelys the intervening extremities 
of the median frontals are continued to the upper border of the external 
nostril. In the present fossil cranium the oblique extremities of the anterior 
frontals are arrested at the distance of four lines from the nasal aperture, which 
is bounded above by two distinct nasal bones ; these bones are joined by su- 
ture to the median frontals, to the anterior frontals, and to the superior max- 
illaries ; the nasal processes of which extend upward, and exclude the anterior 
frontals from the nasal boundary. The superior maxillaries are traversed 
obliquely by a large and deep scutal impression, above which the superior 
maxillary forms a convex prominence at the anterior part of the orbit. The 
scutal groove which traverses the median frontals is as strongly marked ; that 
which impresses the post-frontals is fainter. The expanded trumpet-shaped 
portion of the tympanic bone comes nearer the upper margin of the cavity 
than in existing Chelones. 

The palatal bones have no true palatal process. The palatal processes of 
the intermaxillary and maxillary bones form an unusually prominent angular 
ridge, running nearly parallel with the trenchant margin of the jaw : the bony 
palate is not extended along the middle line beyond the intermaxillaries. The 
pterygoid bones present moderately wide and deep external emarginations. 

In. Lin. 

Length of the cranium from the occipital tubercle . 2 3 

Breadth of the cranium above the tympanic cavities . 1 6 

Depth of the cranium at the parietal bones .... 1 

Antero-posterior diameter of the orbit 10 

Breadth of the interorbital space 8 

Chelone Benstedi, nob. 
Emys Benstedi, Mantell. , 

Although very characteristic remains of Chelonian reptiles have been de- 
termined by Cuvier, from the cretaceous beds of St. Peter's Mount, near 
Maestricht, no evidence of the present order of Reptiles in British chalk 
formations had been made public until my description of a Chelonite from 
the lower chalk at Burham, Kent, in the museum of Sir P. Egerton, appeared 
in the Proceedings of the Geological Society. This Chelonite consisted of 
four marginal plates of the carapace, and a few other obscure fragments, 
sufficient to prove that the species was not Trionyx or Testudo : and as they 
differed in form from those of the recent species of Chelone, with which I 
compared them, and resembled rather the posterior marginal plates of some 
Emydians, I stated that this correspondence " rendered it probable that these 
remains are referable to that family of Chelonia which lives in fresh water or 
estuaries." Subsequent observation of the various interesting modifications 
by which extinct Chelones diminish, as it were, the gap between the marine 
and freshwater genera as they remain at the present day, has weakened the 
impression which the character of the marginal plates of the chalk Chelo- 
nite first made in favour of its Emydian affinities ; and the examination of the 
beautiful Chelonite, obtained from the same quarries at Burham, and relieved 
from the chalk matrix by Mr. Bensted, lately described and figured by Dr. 
Mantell in the Philosophical Transactions, has demonstrated that it is not an 
Emys but a true Chelone. 



174 REPORT — 1841. 

The fossil in question consists of nearly the whole carapace, and a con- 
siderable portion of the plastron, with a coracoid bone. 

The carapace includes all the dorsal or vertebral plates, save the first; the 
usual number of expanded ribs, viz. eight pairs ; and the entire border of 
marginal plates, save the three first. In the sternum the hyosternal and hy- 
posternal bones may be distinguished. The general form of the carapace is 
elliptical, terminated by a point at the narrower posterior end, Avhich, how- 
ever, is less contracted than in other Chelones. It is as depressed as in Che- 
lones generally. To judge from the unniutilated vertebral plates, which are 
the four last, the carapace appears to have been traversed by a median longi- 
tudinal crest, from which the sides gently slope with a slight convex curva- 
ture, as in Chelone mydas. 

The more immediate indications of the close affinity of the fossil to the 
marine turtles are given by the incomplete ossification and anchylosis of the 
ribs and sternal bones, the latter being in consequence dislocated from each 
other ; and more especially by the shape and size of the marginal plates at- 
tached to the third, fourth, fifth, and sixth ribS; as also by the form and 
length of the coracoid bone. 

The vertebral plates are as narrow relatively as in the ordinary Chelones ; 
but their precise form can only be distinguished in the three last. The ninth*, 
or that to which the eighth rib is in part articulated, is 3 lines in length and 
2 in breadth ; the tenth expands posteriorly into a triangular form ; both 
these have their middle part raised into a ridge ; the eleventh plate is sud- 
denly expanded, with angular sides, which slope away from a median longi- 
tudinal ridge : this is crossed by a transverse ridge just anterior to the junc- 
tion of the plate with the median terminal plate of the marginal series, which 
is convex above and traversed by a median longitudinal furrow. The margins 
of this plate meet posteriorly at an open angle. The second to the seventh 
pairs of expanded ribs are joined together only along their vertebral halves. 
The length of the expanded part of the third rib is 9 lines ; its narrow, 
tooth-like part, before it reaches the marginal plate, is also 9 lines ; about 3 
lines of its extremity is inserted into the deep groove of the concave surface 
of the marginal plate. The width of the interspace between the narrow parts 
of the third and fourth ribs is 4 lines ; the length of the expanded part of the 
first rib is IO5 lines; the breadth of the expanded part of the first rib is 8 
lines ; the length of the narrow end of the rib, clear of the marginal plate, 
is 3 lines. In the superior bi'eadth of the first rib the Chelone Bensledi agrees 
with existing turtles, and differs strikingly from the Purbeck species. The 
last short rib sends, almost directly backwards, a short, narrow, tooth-like 
process, at right angles to the anterior margin of its sub-triangular expanded 
part. In Chelone obovata it is extended more nearly parallel with the ex- 
panded part. 

The marginal plates have the same general uniformity of size which we 
observe in the existing Chelones ; the posterior ones are not expanded as in 
the Purbeck Chelone, and in certain Emydes, as Emys serrata. See. ; but the 
most decisive evidence against the Emydian affinities of the present fossil is 
afforded by the form and development of the inferior borders of the marginal 
plates attached to the fourth, fifth, and sixth ribs; for these plates, instead of 
being expanded and extended inwards to join the hyo- and hyposternals, and to 
combine with these elements of the plastron in forming the lateral supporting 
wall of the carapace, are not so much developed in breadth as the same parts of 
the posterior marginal plates, but form with them an even free border, as in other 
Chelones; in which not any of the marginal plates are joined with the sternum. 
* In all Emydes the proportions of this plate are the reverse of those in the fossil. 



ON BRITISH FOSSIL REPTILES. 175 

With reference to the general imperfect ossification of the carapace, the 
deductions in favour of the marine nature of the Chalk Chelonite might be 
invalidated by the hypothesis that it was the young of some very large spe- 
cies of Emys ; but the existing Emydians, at the immature period when they 
exhibit the incomplete ossification of the carapace and plastron, have the 
marginal plates opposite the lateral processes of the hyosternals and hypo- 
sternals joined with those processes by an inward development of their in- 
ferior border, which is suddenly and considerably broader than the inferior 
border of the contiguous free marginal plates. The outer contour of the 
ninth, tenth, and eleventh plates projects in the form of a slight angle, and 
thus differs from the same parts of Chelone mydas and Chelone obovata ; the 
others have a straight free margin. The marginal plates appear as if bent 
upon themselves to form their outer margin, at a rather acute angle, receiving 
the extremities of the rib in a depression excavated in the concavity of the 
angle ; they are nearly twice as long in the direction parallel with the margin 
of the carapace than transverse to it, and are traversed in the latter direction 
along the middle of their upper surface with the groove or impression of the 
marginal scutes. The free edge of the upjier plate of the marginal pieces is 
slightly notched above the insertion of the rib, and they correspond with 
those of the Chelonite from the Burham chalk-pit in the collection of Sir 
P. Egerton. The form of the median or vertebral scutes is only to be traced 
at the anterior part of the carapace, but their relative breadth and the out- 
ward extension of their lateral angles correspond, like the characters of the 
more enduring parts, with the type of structure of the marine turtles. The 
breadth of the first vertebral scute is 1 inch 8 lines, that of the second scute 
is 2 inches. 

The coracoid bone varies in form so as to be very characteristic of the dif- 
ferent genera of Chelonians ; it is a triangular plate in Testudo, a more elon- 
gated triangle in Chelys, a broad bent elongated plate in Trionyx, a narrower 
bent plate in Emys, a long, straight, slender bone, slightly expanded and 
flattened at the sternal end, in Chelone : now it is precisely the latter form 
that this bone, fortunately preserved in the present specimen, here exhibits, 
showing that the same modifications of the skeleton are combined in the past 
as in the present species of Chelone ; it is 1 inch 7 lines in length, cylindrical 
at its humeral half, and gently expanded to a breadth of 3 lines at its sternal 
end. The proportion which this bone presents of one-fourth the length of 
the carapace is only paralleled in the existing Chelones ; it is much shorter 
in the Emydes. 

The hyosternal and hyposternal bones resemble rather those of the turtles 
than of the young Emydes ; certainly no Emys, with a carapace 5 inches in 
length, presents such forms as these bones exhibit in the present fossil; 
several rays or pointed spines of bone are developed from the anterior half of 
the median margin of the hyosternal piece, as in Chelone caretta ; the rest of 
the margin contributes to form the circumference of the large central aper- 
ture of the sternum. The hyposternal sends similar rays from the posterior 
half of its outer margin, leaving the anterior half to join, probably the same 
proportion of the outer margin of the hyosternal, so as to form a deep lateral 
angular notch of the sternum. The length of the hyposternal is 1 inch 
2 lines. The epi-, ento- and xiphisternal bones ai-e not preserved. 

From the preceding description it must be obvious, as has been already 
observed, that the present Chelonite of the chalk can only be supposed to 
belong to the genus Emys, on the supposition that it is a very young spe- 
cimen of some unusually large species : but against this supposition, the 
pointed form of the hind end of the carapace, the regularity of the size of 



176 REPORT — 1841. 

the marginal plates, tlie non-development of the lower margin of any of these 
plates for a junction Avith the plastron, the narrow elongate form of the ver- 
tebral plates, and the broad vertebral scutes, collectively and separately mili- 
tate ; whilst in all these modifications the Turtle from the Chalk so closely 
corresponds with the true Chelones, that I cannot hesitate to refer it to the 
marine family of the order. , 

From the breadth of the xiphisternals in the remains of this species first 
described by me, I was induced to suppose that a new subgenus ( Cimochelys) 
of marine Turtles was thereby indicated, having a closer affinity to the Emydes 
than the typical species ; and the same affinity seems to be shown by the 
more regular elliptical form of the carapace of Mr. Bensted's beautiful spe- 
cimen. The structure of the cranium, when this desirable part of the skeleton 
is discovered, may confirm the propriety of the subgeneric distinction ; but 
the numerous decided marks of closer affinity to Clielone leave no alternative 
than to regard the fossil species of the chalk as a member of that genus. 

It difi'ers from all known species, especially the sub-carinated species of 
Sheppey, in the form of the carapace, which is more truly elliptical than in 
any other species with which I am acquainted. 

I have been favoured with. the opportunity of inspecting portions of the 
skeleton of a large Chelonian obtained by Mrs. Smith, of Tonbridge Wells, 
from the lower chalk at Burham, Kent, and skilfully relieved from iheir 
mineral bed by that lady. The principal bones consist of two series, one 
containing five, the other four, of the marginal plates of the carapace, in 
natural connection, and from that part of the margin where they receive the 
extremities of the vertebral ribs. These marginal plates in Chelone mydas 
are three-sided, and have two terminal surfaces by which they are united, 
suturally, to one another : of the three free surfaces, the one, directed towards 
the interior of the body, is characterized by a deep depression for the recep- 
tion of the tooth-like extremity of the rib ; the two otlaer (upper and under) 
surfaces meet at an angle, which is produced at certain parts to form the 
marginal dentations of the lateral and posterior parts of the carapace in that 
species of turtle, but is more open and obtuse in the marginal plates at 
the anterior part of the carapace. In the fossil the marginal plates have the 
general characters of those of the genus Clielone, but differ from those of the 
Chelone mydas, in being more concave on the central or perforated side, and 
they are also concave at the upper side, and in a slighter degree at the under 
side ; these sides likewise meet at a more acute angle, and this angle is pro- 
duced into a sharper and more continuous ridge : but this ridge subsides at 
one end of the series of five plates, and the upper and under sides gradually 
meet at a more open angle, which is rounded off in the first of the series. 
This plate, therefore, answers to the third marginal plate in the Chelone 
mydas, or that which receives the end of the first expanded vertebral rib ; 
and the remainder, therefore, to the fourth, fifth, sixth, and seventh marginal 
plates : now these are precisely the marginal plates in the Ernys, which have 
their inferior margins developed inwards and articulated by suture to the 
lateral wall of the carapace : but these margins not being so developed or 
terminated in the present fossil, but, on the contrary, being inferior to the 
upper margin in breadth*, and terminating like that margin in a blunted 
edge, prove the present Chelonite to belong, like the smaller Chelonite from 
the same chalk-pit already described, to the marine genus Chelone. 

The following admeasurements will show the different proportions of the 

* The upper margin, which is distinguished by a slight notch where the costal groove leads 
to the pit, is broader than the lower one, in these plates of the Chelone mydas ; but the dif- 
ference is less than in the present fossil species. 



Foss 


ilChel. 


Chel. mi/das. 


In. 


Liu. 


111. Lin. 


7 


3 


8 2 


1 


1 


10 


1 


2 


1 6 



ON BRITISH FOSSIL REPTILES. 1/7 

marginal plates of the present specimen as compared with the corresponding 
ones of a Cheloiie mi/das of similar general size : — 

Length of the series of five plates in a straiglit line 
Breadth of the upper surface of the third (fiftii) . 
Interspace of costal depressions 

Thus the marginal plates of the chalk turtle, besides being more concave, 
are broader in proportion to their length, or antero-posterior diameter. In 
these respects they correspond with the form of the marginal plates in the 
Chelone Benstedi, and most probably belong to a larger and older specimen of 
the same species. 

There are two other marginal plates imbedded in the same portion of 
chalk, Avith their ujiper, smooth, slightly concave surfaces exposed; and the 
toothed or sternal extremities of three of the vertebral ribs, which by their 
length and size also prove this specimen to be a turtle. One of these frag- 
ments of rib measures 5h inches, and the expanded plates developed from 
each side of its upper surface are concave on their exterior surface, which is 
flat or slightly convex in Cheloiie mydas. 

A separate portion of chalk from the same pit contains the scapula and its 
acromial branch or anchylosed clavicle, with the articular surface which joins 
with the coracoid and humerus. The angle at which the scapula and clavicle 
meet is more open in Chelone than in Emys or Chelys : the present specimen 
presents the same angle as in the Maestricht Chelone figured by Cuvier *, in 
which it is rather more open than in the recent species of turtle. A broad, 
thin, slightly concave plate of bone appears, by the radiation of the fine 
striaj at its under part, to represent the expanded parietal bone of the 
cranium. 

The carapace of the turtle to Avhich the fragments above described be- 
longed, must have been nearly if not quite two feet in length. 

Eocene Tertiary Chelones. — Although both the leading divisions of fresh- 
water Chelonians are represented in the Eocene tertiary formations of Great 
Britain, the one by the Emys testudiniformis, the other by the Plaiemys or 
Hydmspis Bullockii, the Chelonian Reptiles from the London clay of Shep- 
pey and Harwich are for the most part true turtles, or species of the genus 
Chelone. Already good evidence of at least five distinct species have been 
obtained from these localities, and it is probable that others remain to be 
discovered ; they are generally of smaller size than the species which are now 
restricted to warmer or intertropical latitudes, and differ from those species, 
as well as from each other, by well-marked characters afforded by the skull, 
the carapace, and the plastron. 

Chelone longiceps — The most common species, Chelone longiceps\, is di- 
stinguished by very interesting modifications both of the cranium and osseous 
buckler, by which it approaches more nearly to the freshwater Chelonians 
than do any of the existing species of Chelone. In the prolongation of the 
conical rostrum and osseous palate, the skull of this species resembles that of 
a Trionyx, but the tem.poral fossae are covered by a roof of bone having the 
characteristic anatomical structure of the true Chelones. The buckler is broader 
in proportion, and both carapace and plastron are more completely ossified 
than in recent turtles ; thus both the hyosternals and hyposternals are broader 

* Ossein. Foss., torn. v. part ii. pL xiv. fig. 5. 

t The characters of this and the other species of Chelone from the Loudon clay forma- 
tion are detailed in ray Memoir on that subject read before the Geological Society, Dec. 1, 
1841, 

184:1. N 



178 REPORT — 1841. 

than they are long ; the xiphisternals are unusually broad. The tooth-like 
processes from the mesial margins of the hyo- and hyposternals are more 
numerous and smaller than in existing species, and interlock with each other, 
so that two margins of each of these bones are joined by suture, instead of 
one, as in almost all other turtles. Yet in the largest specimens of this species 
which I have seen, the centre of the sternum remains unossified, its sides un- 
united by bone with the. carapace, and the external and part of the internal 
margins of its constituent bones preserve their separated tooth-like rays. 

The small specimen of which the plastron is figured by Parkinson and by 
Cuvier, belongs to the present species of Chelone ; it is now preserved in the 
rich collection of Prof. Bell. In the same collection there is preserved a 
specimen of Chelone longiceps, the plastron of which is 8 inches in length 
and nearly 8 inches in breadth ; in this specimen, which is the largest of the 
present species that I have seen, the central vacuity of the plastron and the 
toothed margins of many of the constituent bones remain. Three of the Che- 
lonites in the museum of Sir P. Egerton, two in that of Mr. Bowerbank, one 
in that of Mr. Dixon, and one in the Hunterian Collection, belong to the 
Chelone longiceps. All these specimens are from the Isle of Sheppey. 

Chelone planimenttim, nob. — The species which, in the number of indi- 
viduals representing it comes next in order after the Chelone longiceps, is 
characterized by a flat and unusually long symphysis of the lower jaw, but 
this is associated with a broad, high, and convex cranium, and with a muzzle 
not longer than in ordinary Chelones. The carapace is characterized by the 
strength of the ribs which traverse the whole of the under part of the ex- 
panded plates in the form of thick convex ridges. 

All the specimens of this species that I have hitherto seen are from the 
Eocene clay of the eastern coast of Essex. A carapace in the British Mu- 
seum measures 13 inches in length and 12 inches across the fourth pair of 
expanded ribs. A skull in the museum of Prof. Sedgwick, associated with a 
carapace and other parts of the skeleton of the same individual, and another 
skull in that of Prof. Bell, indicate that the head was relatiA'ely as large in 
the Chelone planimentum as in the Chelone imhricata. 

Chelone breviceps, nob. — This species, in the narrow, ovate, and posteriorly 
pointed carapace, and in the less extensive ossification of the sternum, re- 
sembles more the recent Chelones than does the Chelone longiceps. Its cra- 
nium also preserves the ordinary form in its depth and in the shortness of its 
muzzle. The external surface of the cranium and osseous buckler is rugous. 
The angles by which the expanded ribs are wedged into the interspaces of the 
vertebral plates have equal or nearly equal sides. It appears to have exceeded 
the Chelone longiceps in size : a portion of the osseous buckler of a Chelone 
breviceps, with a carapace 16 inches in length, is preserved in the museum of 
Mr. Robertson, surgeon, at Chatham. 

Smaller specimens of the Chelone breviceps, all from the Isle of Sheppey 
are preserved in the Hunterian Collection, in the museum of Prof. Bell, and 
in that of Mr. Bowerbank. Mr. Bowerbank's specimen exhibits the head in 
connection with the carapace and plastron, and is the most beautiful Chelo- 
nite, perhaps, that has yet been obtained from any formation. 

Chelone convexa, nob The surface of the bony buckler of this species, 

like that of the Chelone longiceps, is smooth, but the forms of the constituent 
bones of the carapace and their degree of ossification differ considerably from 
those of a Chelone longiceps of the same size, and resemble those of Chelone 
mydas. The carapace is more convex than in the preceding species from 
Sheppey, and than in the existing Chelones, whence the specific name of the 
present extinct species. It is from the Isle of Sheppey. 



i 



ON BRITISH FOSSIL REPTILES. 179 

Chelone suheristata, nob. — This species, also from the Isle of Sheppey, has 
the usual thalassian form of carapace, which is narrow, ovate, and contracted 
to a point behind, with a sternum resembling also existing Chelones, in the 
form and degree of ossification of its constituent pieces, and the slenderness 
of the xiphisternals. It may be distinguished from the Chelone breviceps by 
the smoothness of its carapace, the different form of the vertebral plates, and 
the development of a sharp ridge on the sixth and eighth vertebral plates. 

The sole example of this species which has come under my observation is 
the osseous buckler, 9 inches in length and 6^ inches in breadth, in the 
museum of Mr. Bowerbank. 

Chelone latiscu^ta, nob. — This species is founded on a nearly complete ' 
buckler of a turtle from Sheppey, measuring 3 inches in length, from the 
second to the seventh plate inclusive : it may be a variety, or the immature 
state of Chelone longiceps, but I have not yet had the opportunity of ascer- 
taining to what extent the relative breadth of the vertebral scutes varies in 
individuals of different age of existing species of turtle. In the present case 
the vertebral scutes are nearly twice as broad in proportion to their length, 
as they are in the Clielone longiceps, or in any of the other well-marked spe- 
cies of Eocene turtles. 

The indications of Chelonites from Eocene strata, in the works of Parkin- 
son, Woodward and Konig, being unaccompanied by the anatomical deduc- 
tions essential to the establishment of their true affinities, have been either 
misinterpreted or neglected ; and except the citation of Woodward's Chelone 
Harvicensis, in M. H. v. Meyer's Compilation*, the existence in the London 
clay of fossil Emydes alone has been recognized in the latest summaries of 
the present branch of Paleontology f. These, therefore, could indicate but 
little difference between the present fauna and that of the Eocene period in 
regard to the Chelonian order. But the case assumes a very different aspect 
when we arrive at the conviction that the majority of Sheppey Chelonites be- 
long to the marine genus Chelone, and reflect that the number of extinct 
Eocene turtles from that limited locality very nearly equals that of all the 
well-determined species of Chelone now known to exist. For notwithstand- 
ing the assiduous search of the naturalist-collector, and the attractions which 
the shell and flesh of turtles offer to the commercial voyager, the tropical 
seas, though so often traversed, have not as yet yielded more than five good 
species of Chelone ; and of these only two, as Chelone mydas and Chelone 
caretta, are known to frequent the same locality. Now, whilst it is obvious 
that but a small proportion of the organized treasures of the vast deposit of 
petrified mud and clay which fills the London Basin have been brought to 
light, the results of the examination of fossil Chelonites evidently show that 
the ancient ocean of the Eocene epoch was more abundantly provided with 
turtles, and that these presented a greater variety of specific modifications 
than the same extent of ocean in any of the warmer parts of the earth at the 
present day. 

The indications which the Sheppey turtles give, in conjunction with the 
other organic remams from the same depository, of the higher temperature 
that prevailed in the latitude in which they lived, cannot be overlooked ; yet 
at the same time the conditions, which allow of the attainment of the size 
which tlie present tropical turtles often exhibit, would seem not to have been 
present in the time and place of existence of the extinct species of Chelone 

* I'alaiologica, p. 104. 

t See Cuvier, Ossem. Fossiles, ed. 183G, 8vo, torn. k. p. 464 ; Bucklawl, Bridgewater 
Treatise, vol. i. p. 258 ; the recent comprehensive work on Erpetolog)', by :MM. Dumeril 
and Bibron, torn. ii. p. 533; and Dr. Grant in the British Annual for 1839, p. 266. 

n2 



180 REPORT— 1841. 

above enumerated ; and again, tlie affinities to the freshwater forms whieli 
the skeleton of some of the Eocene Clcelones exhibit, accord with the indi- 
cations tiiat tiicy inhabited the estuary of a great river. 

Order OPHIDIA. 

In the Appendix to the second 4to edition of the ' Ossemens Fossiles,' Cu- 
vier remarks, " Les os de serpens sent encore phis rares, s'il est possible. Je 
n'en ai vu que des vertebres des breches osseuses de Cette, dont j'ai parle tl 
Tarticle de ces breches, et une seule des terrains d'eau douce de I'ile de Shep- 
pey*." 

The'Ophidiolites from this formation have been the subject of a memoir 
by me, pubUshed in the sixth volume (second series) of the Geological Trans- 
actions, in which the best-preserved specimens in the collections of John 
Hunter and Mr. Bowerbank are described. The Hunterian Ophidiolites 
were referred by the Founder of the collection, in the original MS. Cata- 
logue, to the Crocodile ; some of those in the private collections I found 
ticketed •' Vertebrae of Tortoise." All these specimens presented the general 
characteristics of the vertebrae of serpents, and resembled in structure as well 
as size those of the Constrictors (Python and Boa^ more than those of the 
colubrine or poisonous families. Very recognizable differences are to be dis- 
cerned in the Eocene fossil vertebrae as compared with the vertebrae of exist- 
ing Pythons and Boae ; they are longer as compared with their height or 
breadth ; the costal tubercle is placed lower down ; the transverse process 
supporting the lower anterior articular process has a greater vertical extent^ 
and the ridge continued from the lower anterior to the lower posterior oblique 
■process is less developed ; the oblique processes do not extend so far outwards, 
and the spinous process is higher, but has a less antero-posterior extent than 
in existing land-serpents. The middle of the posterior margin of the neura- 
pophysis, opposite the external angle of the articular excavation or mortise, 
is produced backwards in the form of an angular plate. The inferior surface 
of the vertebra is not longitudinally carinated, as in some Coluhri, but has a 
tubercle at the middle of the anterior part, as in the Python. 

These differences justify the consideration of the Sheppey Ophidiolite as 
the representative of a distinct genus as well as species, for which I have pro- 
posed the name of Palceophis toliapiciis. 

The largest of the Ophidiolites in Mr. Bowerbank's collection exhibits a 
portion of the vertebral column suddenly bent upon itself, including about 
thirty vertebrte, and indicating the usual lateral flexibility of the spine. The 
Hunterian specimen also consists of a group of as many vertebras more dis- 
jointed, and cemented, with a number of long and slender ribs, irregularly 
together by a mass of indurated clay. In the ■museum of Mr. SauU a few 
vertebrae, and a fragment of the skull of the same Palaoplds, likewise from 
Sheppey, are preserved. The size of the vertebrae in the foregoing speci- 
mens corresponds with that of the vertebrae of a boa constrictor of 10 or 
12 feet in length. 

Vertebrae of a serpent agreeing in character with those of the London 
clay at Sheppey, but smaller, have been obtained by Mr. Colchester, from 
the sand of the Eocene formation underlying the Red Crag at Kyson or 
Kingston in Suffolk. These have also the small tubercle at the under and 
back part of the body of the vertebra, instead of the ridge, as in Coluber and 
Naja ; and thus, like the larger vertebrae from Sheppey, they come nearer to 
the Python ; but the bodies of these vertebra; are longer in proportion to 
their breadth, as in the Sheppey PalwopMs. The tubercle for the rib is 

* Tom. V. part ii. p. 526. 



I 



ON BRITISH FOSSIL REPTILES. 181 

single ; in Naja it is almost divided into two, the upper being convex, the 
lower moiety concave ; in the Python the upper half of the tubercle is con- 
vex and the lower half concave, but the two facets are not marked oft". In the 
Palccoplds, of both Sheppey and Kyson, it is simply convex. 

The most perfectly preserved, as well as the largest specimens of vertebrae 
of Palceophis which I have seen, are from the Eocene clay at Bracklesham, 
and are preserved in the select collection of Fr. Dixon, Esq. of Worthing. 
The serpent to which the largest of these vertebrae belonged must have been 
upwards of 20 feet in length. 

Ophidian reptiles, of ten, twelve, and twenty feet in length, exist in the 
jiresent day only in intertropical regions, and they for the most part prey on 
mammals and birds. If, therefore, direct evidence of species of both these 
warm-blooded classes in the London clay had not been obtained*, they might 
have been strongly suspected to have co-existed with serpents of such dimen- 
sions as those to which the vertebrae and ribs above mentioned belonged. 

Order BATRACHIA. 

Of this order of Reptiles, represented in the present Fauna of Great 
Britain by a few diminutive species of frogs, toads, and newts, the remains 
of some remarkable extinct members have been discovered in the New Red 
SandstQue of Warwickshire. 

As the determination of these fragments has been the result of the exami- 
nation, in part microscopical, of detached bones and fragments of bone and 
teeth, and since the Batrachian order, like most others at the confines of a 
great natural group, exhibits wide modifications of its typical structure, a ievi 
words may be expected touching the grounds for referring the fossils in 
question to the Batrachian order, especially since similar fossils in another 
country, specimens of the same species, have been regarded as parts of 
Saurians. 

The Batrachians have no fixed type of external form like the higher orders 
of Reptiles, but some, as the broad and flat-bodied toads and frogs, most 
resemble the Chelonians, especially the soft-skinned mud-tortoises ( Trionyx) ; 
other Batrachians, as the CcEcilia', resemble Ophidians ; a third group, as the 
Newts and Salamanders, represent the Lacertians ; and among the Perenni- 
branchiate reptiles there are species which combine with external gills the 
mutilated condition of the apodal fishes. 

Thus it will be perceived, that, even if the entire skeleton of one of the 
New Red Sandstone Batrachians had been obtained, there is no fixed or cha- 
racteristic general outward ibrm in the Batrachian order whereby its affinity 
to that group could have been determined. The common characters by which 
the Batrachians, so diversified in other respects, are naturally associated into 
one group or suborder of reptiles, besides being taken from the condition of 
the circulating and generative systems and other perishable parts, are, how- 
ever, fortunately as strongly manifested in modifications of th« skeleton and 
principally in the skull. This is joined to the atlas by the medium of two tu- 
bercles, developed exclusively from the lateral occipitals ; the bony palate is 
formed chiefly by two broad and flat bones, called ' vomerine' by Cuvier, and 
generally supj)orting teeth. It is only in the Batrachians among reptiles that 
examples are found of two or more rows of teeth on the same bone, espe- 
cially on the lower jaw (Cacilia;, Sireties). With regard to vertebral cha- 
racters, no such absolute Batrachian modifications can be adduced as those 
above cited from the anatomy of the cranium. Some Batrachians, as is well 
known, have the vertebra; united by ball-and-socket joints, as in most recent 
* Geological Transactions, second series, vol. vi. p. 203, pi. 21. 



182 REPORT — 1841. 

reptiles; others by biconcave joints, as in a few recent and most extinct 
Saurians. Some species have ribs, others want those appendages ; the pos- 
session of ribs, therefore, even if longer than those of the CcBcilicB, by a 
fossil reptile combining all the essential Batrachian characters of the skull, 
would not be sufficient ground for pronouncing such reptile to be a Saurian. 
Much less could its Saurian nature be pronounced from the circumstance of 
its possessing large conical striated teeth ; as the ordinary characters of size, 
form, number, and even presence or absence of teeth, varies much in existing 
Batrachians, the location of teeth on the vomerine bones being the only con- 
stant dental character in which they differ from all other orders of reptiles. 

My first acquaintance with the remarkable fossils under consideration was 
founded on the examination of portions of teeth, from the new red sandstone 
of Coton End quarry, Warwickshire, transmitted to me by Dr. Lloyd of Lea- 
mington. The external characters of these teeth corresponded with those 
which had previously been discovered, by Prof. Jaeger, in the German Keuper 
formation in Wirtemberg, and on which the genus Mastodonsaurus had been 
found. 

The results of a microscopic examination of the teeth of the Mastodon- 
saurus from the German Keuper, and of those from the New Red Sandstone 
of Warwickshire, have been detailed in the Proceedings of the Geological 
Society, January 1841, and illustrated in my ' Odontography,' pp. 195 — 217, 
pis. 63, 63 A, 63 B, 64, 64 a, 64 b. They proved that the teeth from both 
localities possessed in common a very remarkable and complicated structure, 
to the principle of which, viz. the convergence of numerous inflected folds of 
the external layer of cement towards the pulp-cavity, a very slight approach 
was made in the fang of the tooth of the Ichthyosaurus, and that a closer ap- 
proximation to the labyrinthine structure in question was made by the teeth of 
several species of fishes, while the teeth of existing Batrachians were simple, 
like those of most Saurians. 

Thus, inasmuch as the extinct animal in question manifested in the intimate 
structure of its teeth an affinity to fishes, it might be expected that, if it actu- 
ally belonged to the class of reptiles, the rest of its structure would manifest 
the characters of the lowest order, viz. the Batrachia, the existing members of 
which pass, though not by the dental character alluded to, yet by so many 
other remarkable degradations of structure, towards fishes. Now it has actu- 
ally happened that, in the same formation in Wirtemberg from which the la- 
byrinthic teeth of the so-called Mastodonsaurus have been derived, a frag- 
ment of the posterior portion of the skull has been obtained, showing the 
apparent absence of the basi-occipital, and the development of a separate 
condyle on each ex -occipital bone; whence Prof. Jaeger, recognizing the 
identity of this structure with the Batrachian character above mentioned, 
founded upon the fossil a new genus of Batrachia, which he called ' Sala- 
mandroides giganteus.' Subsequent discoveries, however, satisfied the Pro- 
fessor that the bi-condylous fragment of skull, representing the genus Sala- 
mandroides, belonged to the same reptile as the teeth, on which he had founded 
the genus Mastodonsaurus. But notwithstanding the evidence thus olitained 
of the Batrachian affinities of the Keuper Reptile, Prof. Jaeger preferred to 
retain for it the name which implied its membership with the Saurian order, 
and cancelled the genus Salamandroides, Avhich form of substantive has, in- 
deed, been forbidden by the canons of botanical nomenclature to be used as 
the name of a genus*. 

I proceed now briefly to notice the fossils from the Warwick sandstone 

* " Nomina generica in o'ides desinentia e foro Botanico releganda sunt." — Linnaei Plii- 
losophia Botanica, 1751, p. 161. 



ON BRITISH FOSSIL REPTILES. 183 

described in my Memoir read before the Geological Society, and in which 
additional, and, as it seems to me, conclusive proof is given of the Batrachian 
nature of the genus to which those fossils belong ; with the establishment of 
five distinct species, one of which is most probably identical with the Masto- 
donsaurus salamandroides of Prof. Jaeger. 

It is scarcely necessary to repeat the reasons which I have given to show 
that the generic denomination Mastodonsaurus cannot be retained ; first, it 
unavoidably recalls the idea of the mammalian genus Mastodon, or else a 
mammilloid form of tooth, whereas, all the teeth of the reptile so called are 
originally, and most of them are permanently of a cuspidate and not of a 
mammilloid form ; secondly, because the second element of the word, saurus, 
indicates the genus to belong to the Saurian and not to the Batrachian order 
of reptiles. For these reasons I have proposed to designate the genus in 
question Labyrinthodon, in allusion to the peculiar and characteristic struc- 
ture of the teeth. 

The specimens which I have examined are referable to five species, viz. 
\. Lahyrinthodon salamandroides; 2. L. leptognathus ; 3. L. pachygnathus ; 
4. L. ventricosus ; and 5. L. scutulatus : and I shall here briefly notice the 
characters exhibited by the bones assignable to the 2nd, 3rd, and 5th species. 

Lahyrinthodon leptognathus. — The remains which I consider as portions of 
this species, consist of fragments of the upper and lower jaws, two vertebrae, 
and a sternum. They were found in tlie sandstone quarries at Coton End, 
near Warwick. 

The portions of the upper jaw show that the maxillary or facial division of 
the skull was broad, much depressed, and flattened, resembling the skull of 
the gigantic Salamander and of the Alligator ; and the outer surface of the 
bones was strongly sculptured, as in the Crocodilian family, but of a relatively 
larger and coarser pattern. One portion of the upper jaw contains the an- 
terior moiety of the single row of small teeth, or thirty sockets, and the base 
of one of the great anterior tusks. The bases of the serial teeth project 
directly from the outer wall of the shallow socket, there being no alveolar 
ridge external to it. The large anterior fang is three times the size of the 
first of the serial teeth, and the size of these gradually diminishes as they are 
placed further back ; the length of the common-sized teeth being about two 
lines, and the greatest breadth one-third of a line. The apical two-thirds of 
each tooth is smooth, but the basal third is fluted, and anchylosed to the outer 
wall of the socket. The breadtli of the upper jaw, opposite the middle of the 
dental series, was two inches six lines ; in proceeding backwards the jaw gra- 
dually expands to three inches, and in proceeding forwards narrows, but in a 
less degree towards the anterior extremity, and then slightly widens or in- 
clines outwards on account of the large tusks. Where the upper jaw is entire, 
^ portion next the median suture, four lines in breadth, is separated from the 
maxillary bone by a longitudinal harmonia, and corresponds with the position 
of the nasal bone in the Crocodile. 

On comparing the structure of the cranium of the Lahyrinthodon with the 
existing Batrachiaus, it is true that an important modification will be found 
to exist. In botli the caducibranchiate and perennibranchiate species, tiie 
upper maxillary bones do not extend horizontally over the upper surface of 
the skull, but leave a very wide interval between the maxillary and nasal 
bones ; and the palatal processes of the former contribute as little to form the 
floor of the nasal cavity : in the Crocodiles, on the contrary, the palatal pro- 
cesses of the maxillary bones extend horizontally inwards, and meet at the 
middle line of tlie roof, forming an unbroken floor to the nasal cavity. In 
tiie Lahyrinthodon the superior maxillary bones, as already shown, extend in- 
wards to the nasal bone, constituting with it a continuous roof to the nasal 



184 REPORT — 1841. 

cavities ; but the palatal processes, instead of reaching to the middle line, as 
in the Crocodiles, are very narrow, as in the Batraclda. The osseous roof of 
the mouth is principally composed of a pair of broad and flat bones, analogous 
to the divided vomer in Batrachia, but of much greater relative extent, ap- 
proaching, in this respect, those of the Menopome, and defending the mouth 
with a more extensive roof of bone than exists in any Lacertian reptile : phy- 
siologically, therefore, the Labyrinthodon, in this part of its structure, comes 
nearest to the Crocodile ; but the structure itself, morphologically, is essen- 
tially Batrachian. In the Menopome and gigantic Salamander, a row of small 
teeth extends transversely across the anterior extremity of the vomerine bones : 
and the occurrence in the Lahyrintliodon of a similar row, consisting in each* 
palatine bone of three median small teeth and two outer larger ones, marks 
most strongly its Batrachian nature ; and from the outermost tooth a longi- 
tudinal row of small and equal-sized teeth is continued backward along the 
exterior margin of the palatine bone. The Avhole of this series of palatal 
teeth is nearly concentric with the maxillary teeth. 

In Lacertine reptiles the examples of a row of palatal teeth are rare, and, 
when present, it is short, and situated towards the back of the palate, upon 
the pterygoid bones, as in the Iguana and Mosasaur. In Batrachians the most 
common disposition of the palatal teeth is a transverse row placed at the ante- 
rior part of the divided vomer, as in Frogs, the Menopome and gigantic Sala- 
mander, and at the posterior part in certain toads. In the Amphiume, on the 
contrary, the palatal teeth form a nearly longitudinal series along the outer 
margin of the vomerine bones. The Lahyrintliodon combines both these dis- 
positions of the palatal teeth, which are arranged transversely across the fore 
part of the divided vomer and extend backwards along its outer margin. 
No teeth are placed on the pterygoid bones at the back of the palate as in 
the Saurians with palatal teeth. The posterior palatine apertures are, how- 
ever, more completely circumscribed by bone than in most Batrachians, and 
occupy the same relative position as in the Iguana. The posterior margin 
only of one of the anterior apertures is exhibited in the specimen here de- 
scribed, but from its curve I infer that the two apertures are not confluent, 
as in the Crocodile, the Frog, or the Menopome, but that they are distant, 
as in the Iguana. 

From the physiological condition of the nasal cavity it may be concluded 
that the Labyrinthodon differed from the Batrachians and resembled the Sau- 
rians in having distinct posterior nasal apertures surrounded by bone, and that 
its mode of respiration was the same as in the higher air-breathing reptiles. 
In the shedding and renewal of the maxillary and the transverse palatal teeth, 
it is evident that the process took place alternately in each row, as in many 
iishes, M-hereby the dental series was always kept in an efficient state. 

Another instructive fossil is a portion of the left ramus of an under jaw 
of Lahyrintliodon leptognatlms from the War^-ick sandstone. It is six inches 
long, slender and straight, the syniphysial extremity is abruptly bent in- 
wards, and it presents almost as striking a Batrachian character as any of the 
bones just mentioned. The angular piece is of great breadth, and is con- 
tinued forward to near the symphysis, forming the whole of the inferior part 
of the jaw, and extending upon the inner as far as upon the outer side of the 
ramus, the inner plate performing the function of the detached os operculare 
in the jaw of Saurians. The dentary bone is supported upon a deep and wide 
groove along the upper surface of the angular piece, which also projects be- 
yond the groove, so as to form a strong convex ridge on the external side of 
the jaw, below the dentary piece. This character, which in the large bull-frog 
{Rana pipiens) is confined to the posterior part of the maxillary ramus, is 
in the Lubyrinthcdon continued to near the anterior extremity. The teeth 



ON BRITISH FOSSIL REPTILES. 185 

are long and slender, gradually diminishing in size towards the anterior portion 
of the jaw, and the fragment presents a linear series of not less than fifty 
sockets, placed alternately a little more internally ; and at the anterior in- 
flected part of the jaw is the base of the socket of a large tooth. The ante- 
rior portion of the jaw being broken off', it is uncertain if the serial teeth were 
continued externally to the anterior tusk, which is a remarkable ichthyoid 
character noticed in another species of Lahyrinthodon. 

The sockets of the teeth are shallower than in the upper jaw ; the outer wall 
is more developed than the inner, and the anchylosed bases of the teeth more 
nearly resemble, in their oblique position, those of existing Batrachia. With 
regard to the modification of the microscopic structure of the teeth, I may ob- 
serve that, between the apex and the part where the inflected vertical folds of 
the cement commence, the tooth resembles, in the simplicity of its intimate 
structure, that of the entire tooth of ordinary Batrachia and most reptiles ; 
and in the lower or basal half of the tooth the structure described in the works 
before quoted commences, and gradually increases in complexity. 

From the long and slender character of this ramus, the length of the head, 
as compared with the breadth, approximates more nearly to Crocodilian pro- 
portions than to tlie ordinary Batrachian ones ; but among existing Batrachia 
it resembles most nearly the Amphiume. 

A dorsal vertebra from Coton End presents further evidence of the Batra- 
chian nature of the Lahyrinthodon. It has concave articular cavities at the 
extremities of the body, a condition now known, among existing reptiles, only 
in the Geckos, and in the lower or perennibranchiate division of Batrachians. 
It is a common structure in extinct Saurians, but the depth of the vertebral 
articular cavities in the Lahyrinthodon exceeds that in the Amphiccelian Cro- 
codilians and in most Plesiosaurs. The body of the vertebra is elongate and 
subcompressed, with a smooth but not regularly curved lateral surface, termi- 
nating below in a slightly produced, longitudinal, median ridge ; and it ex- 
hibits the same exceptional condition in the Reptilian class as do the vertebrae 
of existing Batrachians, in having the superior arch or neurapophysis anchy- 
losed with the centrum. From each side of the base of the neural arch a thick 
and strong transverse process extends obliquely outwards and upwards. 

A symmetrical bone, resembling the episternum of the Ichthyosaurus, was 
associated with the preceding remains. It consists of a stem or middle, which 
gradually thickens to the upper end, where cross-pieces are given off at right 
angles to the stem, and support on each a pretty deep and wide groove indi- 
cating strongly the presence of clavicles, and thus pointing out another di- 
stinction from Crocodiles, in which clavicles are wanting. Most Batrachians 
possess these bones. 

The modifications of the jaws, and more especially those of the bony palate 
of the Lahyrinthodon leptognathus, prove the fossil to have been essentially 
Batrachian, but with affinities to the higher Sauria, leading, in the form of the 
skull and the sculpturing of the cranial bones, to the Crocodilian group, in 
the collocation of the larger fangs at the anterior extremities of the jav's to 
the Plesiosaurus, and in one part of the dental structure, in the form of the 
episternum, and the biconcave vertebra;, to the Ichthyosatiriis. Another 
marked peculiarity in this fossil is the anchylosis of the base of the teeth to 
distinct and shallow sockets, by which it is made to resemble the Sphyrasna 
aiul certain other fishes. From the absence of any trace of excavation at the 
iimer side of the base of the functional teeth, or of alveoli of reserve for the 
successional teeth, it may be concluded that the teeth were reproduced, as iu 
the lower Batrachians and in many fishes, especially the higher Chondroptery- 
gii, which formed t\ia Am jjhibia Nantes of Linnaius, in the soft nmcous mem- 
brane which covered the alveolar margin, and that they subsequently became 



186 REPORT — 1841. 

fixed to the bone by anchylosis, as in the Pike and Lophius. This anatomical 
fact militates strongly against the idea tliat the Labyrinthodon is a Saurian *. 
No remains of the locomotive organs of the L. leptognathus have yet been 
found. 

Labyrinthodon pachygnatlms. — The remains of this species, which have been 
obtained, consist of portions of the lower and upper jaws, an anterior frontal 
bone, a fractured humerus, an ilium with a great part of the acetabulum, the 
head of a femur, and two ungual phalanges. A portion, nine and a half inches 
long, of a right ramus of a lower jaw, in addition to the characters common to it 
and the fragment of the lower jaw of the L. leptognathus, in the structure of 
the angular and dentary pieces, shows that the outer wall of the alveolar process 
is not higher than the inner, as in Frogs and Toads, the Salamanders and Me- 
nopome, in all of which the base of the teeth is anchylosed to the inner side 
of an external alveolar plate. The smaller serial teeth ai'e about forty in num- 
ber, and gradually diminish in size as they approach both ends, but chiefly so 
towards the anterior part of the jaw. The sockets are close together, and the 
alternate ones are empty. The great laniary teeth were apparently three in 
each symphysis, and the length of the largest is considered to have been one 
and a half inch. A section through the base of the anterior tusk above the 
socket exhibits the structure described in the Proceedings of the Geological 
Society, January, 1841, but a section of the second tusk, also taken above the 
socket, shows a less complex modification of the labyrinthic arrangement, one, 
viz. which is closely analogous to that at the base of the teeth of the Ichthyo- 
saurus. The apical half of the tusks has a smooth and polished surface, and 
the pulp-cavity is continued, of small size, into the centre of this part of the 
tooth. In the serial teeth, which in other respects, except size, correspond 
with the preceding description of the tusks, the central pulp-cavity is more 
quickly obliterated, but the alveoli are large, moderately deep and complete: 
the texture of the teeth is dense and brittle. The base of each tooth is an- 
chylosed to the bottom of its socket, as in Scomberoid and Sauroid fishes; but 
the Labyrinthodon possesses a still more ichthyic character in the continua- 
tion, preserved in this specimen, of a row of small teeth anterior and external 
to the two or three larger tusks. A double row of teeth thus occasioned does 
not exist in the maxillary bones, either superior or inferior, of any Saurian 
I'eptilef ; but in Batrachia it has been noticed in the lower jaw of the Ccecilia, 
and it is not an uncommon structure in fishes. 

A fragment of the superior maxillary bone manifests a striking deviation 
from the Crocodilian type of structure in the continuation of the palatal plate 
of the intermaxillary bone for about an inch to the outer side of the base of 
the external plate or process ; while in the Crocodiles the external wall of the 
intermaxillary bone is united by the whole of its outer margin with the maxil- 
lary, and is thence continued along the whole outer contour of the intermax- 
illary bone. Now in the Labyrinthodon the intermaxillary bone presents the 
same peculiar modification of the Batrachian condition of this bone as in the 
higher organized Batrachia, the palatal process of the intermaxillary extending 
beyond the outer plate both externally and, though in a less degree, internally, 
where it forms part of the boundary of the anterior palatal foramen, whence 
the outer plate rises in the form of a compressed process from a longitudinal 
tract in the upper part of the palatal process ; it is here broken off' near its 
margin, and the fractured surface gives the breadth of the base of the outer 

* It would be highly desirable to determine in how many of the characters above detailed 
the Nothosaurus mirabilis, Muenster, may dexdate, like the Labyrinthodon, from the Saurian 
type of structure : it would seem to connect the Plesiosaurus with the Labyrinthodon. 

t The successional teeth in Plesiosaurus and Not/iosaurus are sometimes so far developed 
before they displace their predecessors as to cause the appearance of a double row. 



ON BRITISH FOSSIL REPTILES. 187 

plate, stamping the fossil with a Batrachian character conspicuous above all 
the Saurian modifications by which the essential nature of the fossil appears 
at first sight to be masked. 

In the anterior frontal bone there are indications of Crocodilian structure. 
Its superior surface is sHghtly convex and pitted with irregular impressions ; 
and from its posterior and outer part it sends downwards a broad and slightly 
concave process, which appears to be the anterior boundary of the orbit. This 
process presents near its upper margin a deep pit, from which a groove is con- 
tinued forwards ; and in tlie corresponding orbital plate of the Crocodile there 
is a similar but smaller foramen. 

From these remains of the cranium of the Lah, pachygnathus, it is evident 
that the facial or maxillary part of the skull was formed in the main after the 
Crocodilian type, but with well-marked Batrachian modifications in the in- 
termaxillary and inferior maxillary bones. The most important fact which 
they show is, that this Sauroid Batrachian had subterminal nostrils, leading to 
a wide and shallow nasal cavity, separated by a broad and almost continuous 
palatal flooring f om the cavity of the mouth ; indicating, with their horizon- 
tal position, that their posterior apertures were placed far behind the anterior 
or external nostrils; whereas in the air-breathing Batrachia the nasal meatus 
is short and vertical, and the internal apertures pierce the anterior part of the 
pjilate. It may be inferred, therefore, that the apparatus for breathing by 
i-nspiration must have been present in the habyrinthodon as in the Crocodile ; 
and hence still further, that the skeleton of the Labyrinthodon will be found 
to be provided with well-developed costal ribs, and not, as in most of the exist- 
ing Batrachians, with merely rudimentary styles. Since the essential condi- 
tion of this defective state of the ribs of Batrachians is well known to be their 
fish-like mode of generation and necessary distension of the abdomen, it is 
probable that the generative economy of these fossil reptiles, in which the 
more complete ribs would prevent the excessive enlargement of the ovaria 
and oviducts, may have been similar to that of Saurian reptiles. 

A fragment of a vertebra of Lab. pachygnathus presents analogous charac- 
ters to the vertebra of the Lab. leptognathus previously noticed. 

Of the few bones of the extremities whicii have come under my inspection, 
one presents all the characteristics of the corresponding part of the humerus 
of a toad or frog, viz. the convex, somewhat transversely extended articular 
end, the internal longitudinal depression, and the well-developed deltoid ridge. 
The length of the fragment is two inches, and the breadth is thirteen lines. 
The ridges are moderately thick and compact, with a central medullary ca- 
vity. In its structure as well as in its general form, the present bone agrees 
with the Batrachian, and differs from the Crocodilian type. 

In the riglit ilium, about six inches in length, and in the acetabulum, there 
is a combination of Crocodilian and Batrachian characters. The acetabular 
cavity is bounded on its upper part by a produced and sharp ridge, as in the 
frog; and not emarginate at its anterior part, as in the crocodile. Above the 
acetabulum in the frog the ilium gives off a broad and depressed process, the 
lower extremity of which is separated from the acetabulum by a smooth con- 
cave groove, I)oth of which are wanting in the crocodile, there being only a 
slight rising of the upper border of the acetabulum. These characters, how- 
ever, are well developed in the Labyrinthodon : but the process, instead of 
being depressed, is compressed, and its internal extremity is pointed and bent 
forwards, representing the rudiment of the long anterior process of the ilium 
in i\w. Batrachia anoura ; but it does not attain in the Labyrinthodon the par- 
allel of the anterior margin of the acetabulum, and the bone terminates in a 
thick truncated extremity a few lines anterior to tlie acetabidum ; which gives 
an essential feature of resemblance to the Crocodiles and difference from the 



188 BEPORT — 1841. 

Batrachians. But the most marked difference in this fossil from the crocodile 
is the length of the ilium posterior to the acetabulum, in which it agrees with 
the analogous portion of the frog and other tailless Batrachians ; while, on 
the contrarj'^, there is an agreement with the Crocodilian type in the mode of 
articulation to the vertebral column. In the frog a transverse process of a 
single vertebra abuts against the anterior extremity of the produced ilium. 
In the crocodile the transverse processes of two vertebrae are thickened and 
expanded, and joined to a rough, concave, articular surface occupying the 
inner side of the ilium, and a little posterior to the acetabular cavity. In the 
Labi/rinthodon is a similar well-marked, rough, elongated, concave, articular 
surface, divided by a non-articular surface, and destined lor the reception of 
the external extremities of two sacral ribs. The Labyrinthodon likewise 
agrees with the crocodile in the lower part of the acetabulum being com- 
pleted by the upper extremity of the pubis, the anterior and inferior part of 
the ilium oifering an obtuse process at the posterior part of the lower boun- 
dary of the acetabular cavity. 

As the fragment of the ilium was discovered in the same quarry as the two 
fragments of the cranium and the portion of the lower jaws, it is probable 
that they niay have belonged to the same animal ; and if so, as the portions 
of the head correspond in size with those of the head of a crocodile six or 
seven feet in length, but the acetabular cavity with tliat of a crocodile twenty- 
five feet in length, then the hinder extremities of the Labyrinthodon must 
have been of disproportionate magnitude compared with those of existing Sau- 
rians, but of approximate magnitude with some of the living anourous Batra- 
chians. That such a reptile, of a size equal to that of the species whose re- 
mains have just been described, existed at the period of the formation of the 
New Red Sandstone, is abundantly manifested by the remains of those singu- 
lar impressions to which the term Cheirotheriiim has been applied. Other 
impressions, as those of the Clieirotherium Hercules, correspond in size with 
the remains of the Labyrinthodon Salamandr aides, which have been dis- 
covered at Guy's Cliff. The head of a femur from the same quarry in which 
the ilium was found exactly fits the acetabulum or the articular cavity of that 
bone. The two toe-bones, or terminal phalanges, resemble those of Batra- 
chians in presenting no trace of a nail, and from their size they may be re- 
ferred to the hind-feet of the L. pachygnathus. 

Thus, all these osseous remains from the Warwick and Leamington sand- 
stones agree with each other and with the fossil remains of the great Masto- 
donsaurus Salamandroides of the German keuper in their essentially Batra- 
chian nature. Now it has been suggested by more than one Palteontologist 
that the impressions of the Cheirotheriiim may have been the foot-prints of 
aBatrachian; but, in consequence of the peculiarities of the impressions, it 
is obvious that the animal must have been quite distinct in the form of its 
feet from any known Batrachian or other reptile. In the attempt to solve 
the difficult problem of the nature of the animal which has impressed the 
New Red Sandstone with the Cheirotherian foot-prints, we cannot overlook 
the fact that we have in the Labyrinthodon also a Batrachian reptile, differ- 
ing as remarkably from all other Batrachians, and from every other reptile in 
the structure of its teeth : both the footsteps and the fossils are, moreover, 
peculiar to the New Red Sandstone ; and the hypothesis that the footsteps of 
the Cheirotheriiim are those of the Labyrinthodo7i, which I have proposed in 
my Memoir read before the Geological Society, may be allowed to be sup- 
ported by more facts than had before been brought to bear upon the question. 

Labyrinthodon scutidatiis. — The remains, to Avhich this specific designation 
has been applied, composed a closely and irregularly aggregated group of 
bones imbedded in sandstone, and manifestly belonging to the same skeleton; 



ON BRITISH FOSSIL REPTILES. 189 

they consist of foui* vertebrtE, portions of ribs, a humerus, a femur, two tibiae, 
one end of a large flat bone, and several small osseous, dermal scutes. The 
mass was discovered in the new red sandstone at Leamington, and was trans- 
mitted to me by Dr. Lloyd in the summer of 1 840. 

The vertebras present biconcave articular surfaces similar to those of the 
other species. In two of them, the surfaces slope in a parallel direction ob- 
li((uely from tlie axis of the vertebrse, as in the dorsal vertebrije of the frog, 
indicating an habitual inflexion of the spine, analogous to that in the humped 
back oi' the frog. The neurapophyses are anchylosed to the vertebral body. 
Tlie spinous process rises from the whole length of the middle line of the 
neurapophysial arch, and its chief peculiarity is the expansion of its elongated 
summit into a horizontally flattened plate, sculptured irregularly on the upper 
surface. A similar flattening of the summit of the elongated spine is exhi- 
bited in the large atlas of the toad. The body of the vertebra? agrees with 
tliat of the L. leptognathus. The humerus is an inch long, regularly convex 
at the proximal extremity, and expanded at both extremities, l)ut contracted 
in the middle. A portion of a somewhat shorter and flatter bone is bent at 
a subacute angle with the distal extremity, and resembles most nearly the 
anchylosed radius and ulna of the Batrachia. 

The femur wants both the extremities ; its shaft is subtrihedral and slightly 
bent, and its walls are thin and compact, including a large medullary cavity. 
The tibias are as long, but thicker and stronger than the femur. They had 
lost their articular extremities, but exhibited that remarkable compression of 
their distal portion which characterizes the corresponding bone in the Ba- 
trachia : they likewise have the longitudinal impression along the middle of 
the flattened surface. The length of the more perfect shaft is 2 inches 1 line. 

With respect to the osseous dermal scuta, tliough they form a striking in- 
stance of tlie Crocodilian affinities of the Leamington fossil, yet as these de- 
tached superficial bones are the most liable to be separated from the frag- 
mentary skeleton of the individual they once clothed, the negative fact of 
their not having been found associated with the remains of the Labyrintho- 
don in other localities, proves nothing in regard to a difference of dermal 
structure between the Leamington and Warwick species. Indeed no anato- 
mist can contemplate the extensive development and bold sculpturing of the 
dermal surface of cranial bones in the Lahyrinthodon pachygnathus and L. 
leptognathus without a suspicion, that the same character may have been mani- 
fested in bony plates of the skin in other parts of the body. Admitting for 
a moment this structure to be proved, to what extent, it will be asked, does 
it aflect the claims of the LahyrintJiodonto be admitted into the order of Ba- 
trachians, in which every known species is covered with a soft, lubricous and 
naked integument, without scales or scuta ? In reply, I have observed*, that 
the skin is the seat of variable characters in all animals ; and, if considered 
apart from the modifications of the osseous and dental systems, is apt to mis- 
lead the naturalist who is in (|uest of the real affinities of a species : thus we 
have in the Trionyx an example of a soft-skinned animal among Chelonian 
reptiles. 

The following are the names of the species of extinct Reptiles in the order 
in which they are described in the second and concluding part of the Re- 
port : — 

Order Enaliosauria. 

Pliosuurus hrachydeirus, Owen. 
Pliosaurus trochanterius, Owen. 

* Geological Proceedings, January 1841. 



190 REPORT— 1841r 

Order Crocodilia. 

Crocodilus Spenceri, Buckland. 

Suchosaurus cultridens, Owen. 

Goniopholis crassidens, Owen. 

Teleosaurus Chapma7ini, Konig. 

Teleosaurus Cadotnensis, Geoft'roy. 

Teleosaurus asthenodeirus, Owen. 

Steneosaiirus brevirostris (rostro-minor), GeofFroy. 

Poikilopleuron Bucklandi, Deslongchanips. 

Streptospondylus Cuvieri, Owen. 

Streptdspondylus major, O. 

Cetiosaurus brevis, 0. 

Cetiosaurus brachyiirus, O. 

Cetiosaurus medius, O. 

Cetiosaurus longus, O. 

Order Dinosauria. 

Megalosaurus Bucklandi, Cuvier. 
HylcEosaurus armatus, Mantell. 
Iguanodon Mantelli, Cuvier. 

Order Lacertilia. 

Mosasaurus Hoffmanni, Conybeare. 

Leiodon anceps, Owen. 

Raphiosaurus subulidens, Owen. 

Lacerta, sp. ind., Eocene. 

Lacerta, sp. ind. (allied to Scincus), Oolite. 

Rhynchosaurus articeps, Owen. 

Thecodo7itosaurus antiquus, Riley and Stutchbury. 

Palceosaurus cylindrodon, Riley and Stutchbury. 

Palceosaurus platyodon, Riley and Stutchbury. 

Cladyodon Lloydii, Owen. 

Order Pterosauria. 

Pterodactylus macronyx, Buckland. 
Pterodactylus, sp. ind. 

Sauria Incertve Sedis. 

PolyptycJiodon, Owen. 
Rysosieus, Owen. 

Order Chelonia. 

Testudo Dy.ncani, Owen. 
Testudo, sp. ind. Oolite. 
Emys testudiniformis, O. 
Platemys Bowerbankii, O. 
Platemys Bullockii, O. 
Platemys Mantelli, Cuvier. 
Tretosternon punctatum, O. 
Emys, sp. ind. Kirameridge Clay. 
Emys, sp. ind. New Red Sandstone. 
Trionyx, sp. ind. 
Cheloim pluniceps, O. 
Chelo7ie obovata, O. 



ON BRITISH FOSSIL REPTILES. 191 

Chelone, sp. ind. Wealden. 
Chelone pulchriceps, O. 
Chelone Benstedi, Owen. 
Chelone longiceps, O. 
Chelone breviceps, O. 
Chelone convexa, O. 
Chelone subcristata, O. 
Chelone latiscutata, O. 

Order Ophidia. 

Palceophis toliapicus. 

Order Batrachia. 

LabyrintJiodon Salamandroides, Owen. 
Labyrinthodon leptognathus, O. 
Labyrinthodon pachygnathus, O. 
Labyrinthodon ventricosus, O. 
Labyrinthodon scutulatus, O. 



SUMMARY. 



A retrospective glance at the catalogue of Reptiles which formerly existed 
on that portion of the earth's surface constituting the present small island of 
Britain, and which are noAv extinct, must call forth such novel and surprising re- 
flections on the dealings of Providence with the animated beings of this planet, 
as may well lead, in the first place, to a questioning of the truth of the af- 
firmations with which the present summary commences. Did the numerous, 
strange, and gigantic representatives of the several orders of Reptiles actually 
at any time live and move and propagate their kind in the localities where 
their bones are now so abundantly found ? Are not these bones the relics 
rather of antediluvian creatures, which perished in the great historical Cata- 
strophe of Water, and have been washed from latitudes suitable to their exist- 
ence to more northern shores ? Are the British Fossil Reptiles actually 
extinct, and may not some living representatives of the Labyrinthodons, 
Enaliosaurs, Dinosaurs, &c., still remain to be discovered in those warmer 
regions where alone large species of reptiles are now known to exist ? 

Such questions and explanations of the phaenomena which are the subject 
of the present Report will be most likely to suggest themselves to those who are 
not conversant with the truths of Geology, and who may never have been eye- 
witnesses of the circumstances under which fossil bones of reptiles are found. 

In many 'cases these circumstances are so opposed to any that can be con- 
ceived to have been produced by the operation of a superincumbent bed of 
waters upon the present surface of the earth during a period of less than one 
year, that the earliest observers to whom the operations of a temporary 
general deluge suggested the first explanation of the appearance of the re- 
mains of a large and strange animal, were irresistibly led to the conviction 
that the conditions under which such fossil animal was found Avere wholly 
inexplicable on the supposition of its carcase having been left by the re- 
tiring waters of a flood. Thus the good Quaker of Whitby, in his letter 
to Dr. Fothergill, recounting the discovery of the extinct species of Croco- 
dile that now bears his name ( Telcosaurus Chapmanni), says, " The bones 
were covered five or six feet with the water every full sea, and were about 
nine or ten yards from the cliff", which is nearly perpendicular, and about sixty 



192 REPORT — 1841. 

yards Iiigh, and is continually weai'ing away by the sea washing against it: 
and, if I may judge by what has happened in my own memory, it must have 
extended beyond these bones less than a century ago. There are several regu- 
lar strata or layers of stone, of some yards thickness, that run along the cliff 
nearly parallel to tlie horizon and to one another. I mention this to obviate an 
objection, that this animal may have been upon the surface, and in a series of 
years may have sunk down to where it lay, which will now appear impossible, 
at least when the stones, &c.. have had their present consistence*." 

It must be obvious, indeed, that the regular succession of horizontal layers, 
— "beginning from the top, of earth, clay, marble, stones, both hard and soft, of 
various thicknesses, till it comes down to the black slate or alum rockf," — 
mounting to the height of near two hundred feet above the petrified skeleton, 
could not have been the result of the deposit of a temporary overflow of di- 
luvial waters continuing for a few months, supposing even those Avaters to 
have been thickly charged with the ruined surface of the old earth. Succes- 
sion of strata, as of all other phsenomena, must take place in successive periods 
of time ; the hundredth layer of lias, counting downwards, which contained 
the skeleton of the strange Crocodile, must once have been the uppermost, and 
some time must have elapsed between the deposition of that stratum with its 
organized contents and the deposition of the succeeding layer above. 

If the fossilized bones of the animals described in the pi-esent memoir had 
been drifted to this island by a flood, they would be found mingled together 
in the superficial strata usually termed ' diluvial,' and would characterize no 
particular formation or locality. But the reverse of this is the fact ; and it is 
the cumulative evidence of the limitation of certain genera to particular for- 
mations that gives its chief value to the present class of researches. 

In the most superficial fossiliferous deposits which indicate the last opera- 
tion of a body of v/ater, either frozen or fluid, upon the surface of the British 
islands, no remains of reptiles have come under my observation. Cuvier alludes 
to a single bone of a crocodile said to have been found associated with the 
usual fossils of the drift or diluvium at Brentford J : but no other evidence 
of any other species or genus of Reptile, which is now confined to warmer 
regions of the globe, has yet been recognized in the British strata called di- 
luvial, or in any that are more recent than the oldest Tertiary formations. 

In these Eocene beds, accumulated in some localities to the thickness of 
three hundred feet and upwards, the remains of crocodiles, tortoises, trio- 
nyxes, turtles, and large serpents, are more or less common. These fossils 
severally exhibit well-marked and unequivocal specific differences when com- 
pared with the bones of their known existing congeners ; but their osteology 
does not present any modifications of generic value. The nearest approach 
to this degree of deviation occurs in the Eocene Chelonian Reptiles, as in 
that species of turtle from Sheppey, which combines the jaws of a Trionyx 
with the bony helmet of a Turtle, and presents an extent of ossification of the 
buckler nearly equalling that of an Erays. The Eocene Crocodile exhibits 
all the characters of the osseous and dental systems M'hich distinguish the 
genus as restricted in the latest systems of Erpetology ; and whilst it cannot 
be identified with any known species, most resembles, not the commonest and 
nearest existing Crocodile, as that of the Nile, but a rarer and more remote 
one, viz. the Crocodilus Schlcgelii of Borneo. Not any species of Reptile of 
the Tertiary strata has been discovered in the chalk upon which those strata 
immediately rest. 

* Philosophical Transactions, 1758, p. 688. t Ibid., p. 789. 

X Dr. Buckland has suggested to me that this bone was probably washed out of the clay 
beneath the diluvium, 



ox BRITISH FOSSIL REPTILES. 193 

A small lizard, closely corresponding in vertebral structure with existing 
species, but differing in its dentition ; and a gigantic marine species (3fosa- 
saiirus), which is the first, in the present descending survey, to offer osteolo- 
gical and dental combinations wholly unknown in existing Saurians, — con- 
stitute the representatives of the Lacertian order in the cretaceous beds, which 
form the most recent of the secondary deposits. 

In tracing upwards the extinct Reptiles we find that the union of the ver- 
tebras by a hinder ball received into an anterior cup, a structure which, with 
an insignificant exception — the Gecko — prevails throughout the Saurian order 
as it now exists, commences with the Lacertian Reptiles which perished du- 
ring the deposition of the chalk, and, in the Crocodilian and Ophidian Rep- 
tiles, is first found in the species which made their appearance during the 
deposition of the London clay. 

Of the Crocodilian order I have yet seen no unequivocal representatives 
from the British chalk. 

All the well-determined Chelonians of the cretaceous period are marine 
species, and are equally distinct, with the Lacertians, from those of the super- 
imposed tertiary beds. 

The most interesting fact which the Palaeontology of the cretaceous period 
has yielded, with reference to the great Saurian division of the class of Rep- 
tiles, is the commencement, or rather the last appearance of the fossil remains 
of an order of Reptiles {Enaliosauria) now altogether extinct. I have de- 
termined portions of the lower jaw with teeth of a large species of Ichthyo- 
saurus from the lower chalk between Folkstone and Dover, which is very 
closely allied to, if not identical with, the Ichthyosaurus communis. The femur 
of a large Plesiosaurus has been obtained from the chalk of Shakspeare's 
Cliff. Remains of more than one species of Plesiosaurus occur in the Gault, 
and are associated with the Ichthyosaurus in the greensand near Cambridge, 
and in the Kentish Rag near Maidstone. 

In the greensand also we first meet with evidences of Reptiles exhibiting 
modifications of structure, especially of the locomotive extremities, as remark- 
able and as different from those of existing species as are presented by the 
Enaliosauria, but pointing as strongly to an adaptation for terrestrial life as 
does the Enaliosaurian structure to aquatic existence. The specimen of the 
unquestionably terrestrial Saurian here alluded to, viz. the Iguanodon, is the 
more remarkable in the subcretaceous marine strata, in consequence of its pre- 
senting the largest proportion of the connected skeleton of the same indivi- 
dual of this species tliat has hitherto been found. 

Gigantic Ci-ocodilian Reptiles, removed by generic modifications of struc- 
ture from the Eocene and existing Crocodiles, now likewise begin to be in- 
dicated, as by the teeth of the Polyptychodon from the greensand quarry at 
Maidstone, and by the large bones of the extremities from the quarries of a 
corresponding stratum at Hythe. 

The Chelonian from the greensand (Chelone pulchriceps) differs from the 
Eocene and all existing turtles in a very interesting modification of the anatomy 
of the cranium. 

In the Wealden group of freshwater strata, the Enaliosaurian order con- 
tinues to be represented by the Plesiosaurus, but no remains of the more 
strictly marine genus. Ichthyosaurus, have yet been discovered. This cir- 
cumstance corresponds with the more strict adaptation for marine existence 
which the structure of the Ichthyosaurus presents, and corroborates the in- 
ference that the Plesiosaurus lived nearer the shore, and ascended estuaries. 
The re-appearance of the Ichthyosaurus in the chalk formations proves that 
it had continued to exist in the neighbouring ocean, and indicates, perhaps, 
ISll. o 



I94 REPORT — 1841. 

that the deposition of the cretaceous beds was related to the formation of the 
Wealden group by proximity of time as well as place. The terrestrial group 
of gigantic Reptiles receives in the Wealden an accession of two new genera, 
viz. Hylceosaurus and Megabsaurus ; and the remains of both these, and 
especially of the Iguanodon, are so abundant, that the Wealden strata may 
be regarded as the metropolis of the Dinosaurian order *. 

The amphibious Crocodiles might be expected, from their known habits at 
the present day, to liave left abundant evidences of their remains in strata, 
which seem to have been deposited at the estuary or mouth of some great 
river ; in a climate, indicated by its vegetable fossils to have been warmer or 
more equable than at present ; and during a period of time which permitted 
the accumulation of 1000 feet of strata. Accordingly, the Crocodilian order 
of Reptiles has been found to be represented by several distinct genera in the 
Wealden formations. 

Some new characters and modifications of structure might also have been 
anticipated in those Crocodilians which existed at a period antecedent to the 
deposition of about 1500 feet of cretaceous strata, which, again, preceded the 
formation of the whole series of superimposed tertiary and diluvial beds. 
Nevertheless, the remarkable modifications which all the Wealden Crocodi- 
lians present in the structure of their vertebrae, as compared with the Eocene 
and existing Crocodiles, could not have been anticipated ; and even now that 
they are ascertained by repeated observation, some of them still remain in- 
explicable in relation to any conjectural habits of the species, or hypotheti- 
cal conditions under which they actually existed. We may understand why 
the ball-and-socket articulation of the vertebras of the present amphibious 
Crocodiles frequenting dry land, should be exchanged for a "joint having 
elastic substance included between two concave articular surfaces, as a struc- 
ture better adapted to Crocodiles more habitually living and moving in water ; 
but these Crocodiles Avith biconcave vertebra are associated with others having 
plano-concave vertebrae, and also with a species having vertebrae joined by 
ball-and-socket articulations. And the difficulty is not diminished by the re- 
markable fact of the latter structure being the rererse of that in i-ecent Ci"o- 
codiles, the ball and the cup having changed places in the extinct Strepto- 
spmidylus ; and having assumed the position which they present in certain 
Sauroid fishes, and in the dorsal and cervical vertebrae of some of the herbivo- 
rous Mammalia. 

The biconcave, plano-concave, and convexo-concave modifications of the 
vertebrae are not the only points in which the extinct Crocodilians of the 
Wealden strata diflPer from those of the London clay and from the existing 
species. The genus GoniophoUs, for example, exhibits a remarkable deve- 
lopment of its dermal armour, the large quadrangular scutes of which, inter- 
locked by teeth received into depressions, are gigantic representations of the 
scales of some of the Ganoid fishes ; Avhile the smaller hexagonal and penta- 
gonal scutes t were articulated together by marginal sutures, as in the dermal 
bony covering of the armadillo. The Poikilopleuron exhibits a medullary 
cavity in the body of the vertebrae, and a double origin of the spinous pro- 
cess. The Suchosaurus offers a very striking change in the form of the 

* Dr. Mantell calculates that not less than seventy individuals of the Iguanodon, varying 
in age and magnitude, from the young just escaped from the shell to the mature animal, with 
a femur of more than a yard in length, have come under his examination ; and he justly oh- 
serves that " more than thrice that number have, in all probability, been destroyed by thg 
workmen, and altogether eluded the observation of the PaJjeoutologist." — See his Memoir in 
the Philosophical Transactions, 1841. 

t These have been discovered since the first sheets of this Report went to press by my 
friend Mr. Holmes of Horsham, in the Wealden strata neai- that town. 



b 



ON BRITISH FOSSIL REPTILES. 195 

teeth. The Ceiiosaurus surpasses all modern Crocodiles in its enormous 
bulk, which almost rivals that of the Whales, its successors in the modern 
seas. 1 he genus Streptospondylus, which, in repeating the ball-and-socket 
structure, offers the strange anomaly of an anterior position of the ball and a 
posterior one of the socket, makes its first appearance in the Wealden by a 
species which must have been little inferior to the Cetiosaurus in length. 

The huge terrestrial Saurians of the Wealden deviate in so much greater 
a degree than the Crocodilians from the existing types, as to render the forma- 
tion of a distinct order for their reception necessary. 

It does not appear that any of the Chelonians of the Wealden period are 
specifically identical with those of the chalk, A new and singular osculant 
genus, Tretosternon, here represents the Trionyces of the Eocene freshwater 
or estuary formations. A new species of Turtle, with an Emydian form of 
shell, occurs in the Purbeck limestone ; and the head of a turtle from the 
Portland stone, upon which the Purbeck beds immediately rest, exhibits the 
same distinction of the separate nasal bones, as does the skull of the turtle 
from the greensand, but combined with well-marked specific differences in 
other parts. 

The Portland stone introduces us to the great Oolitic series, in which we 
lose sight of the Jguanodon, Hylceosaurus, Goniopholis, and Suchosaurus, 
but find that the Megalosaurus, Poikilopleuron, Cetiosaurus, Streptospon- 
dylus, and Plesiosaurus, are genera common to the Wealden and Oolitic 
periods. 

Now also the genus Ichthyosaurus, which was represented by a single 
species in the chalk epoch, astonishes us by the number of individuals, and 
the great variety of specific modifications and varieties of form and bulk, 
under which it existed in the oolitic periods ; especially in the older divisions 
of the oolite, as the lias. The number and variety of Plesiosaurian Reptiles 
are even more surprising, and the modifications of their skeleton being more 
marked and various, proportionally facilitate the determination of the species. 
The largest of these Plesiosaurian Reptiles deviates, indeed, so far from the 
typical structure of the genus as to merit subgeneric distinction. This sub- 
genus, the Pliosaurus, characterizes the Kimmeridge and Oxford clays, but 
appears not to have existed at the period of the lower oolite. 

In the place of the Goniopholis and Suchosaurus, the Crocodilian genera, 
Sfeneosaurus and Teleosaurus, with the subgenera, Aelodon, Mystriosaurus, 
Macrospondylus, &c. (separated, perhaps, without sufficient reason, from the 
first two typical genera of Amphicoelian Crocodiles), make their appearance 
in the oolitic strata, especially in the lower divisions. The long and narrow 
snouts, sharp and slender teeth, short fore-limbs, and imbricated scutation of 
these extinct Crocodilians, attest, with their vertebral structure, their adapta- 
tion to an aquatic life, and to the capture of a prey not more highly or- 
ganized than fishes. 

Some small species of Crocodilians and Lacertians have left a few bones 
of their extremities in the oolitic slate of Stonesfield ; and a most singular 
order of Reptiles now makes its appearance, the skeleton of which exhibits 
a modification of the Lacertian type of structure closely analogous to that 
by virtue of which the mammalian Bat is endowed with the powers of fiight. 
Tiie flying Dragons, called Pterodactyli, were of small size, and are restricted, 
like the Teleosauri and Steneosauri, to the oolitic group. All the other genera 
are continued into the Wealden, — the Poikilopleuron and Megalosaurus, by 
identical species, — the other genera by species which are distinct from those 
of the oolite. The Plesiosaurus and Ichthyosaurus existed, as we have seen, 
as late as the deposition of the chalk. The analogy between the extinct Rep- 

o2 



196 REPOUT~1841. 

tiles and Fishes, in regard to the great proportion of genera which are com- 
mon to the Wcaklen and Oolite, and the small proportion which is continued 
into the Cretaceous formations, offers a valuable corroboration of the subordi- 
nate character of the Wealden group as a member of the great Oolitic series. 

No species or genus of Saurian represented by fossils from the Oolite has 
yet been discovered in older or lower strata in the British Islands. The Rys- 
osteus is apparently confined to the bone-bed under the lias, which may be 
regarded as the oldest member of the Oolitic series in these islands. 

The Reptiles of the Poikilltic strata exhibit deviations from the typical 
structure of the recent families, together with osculant characters joining 
groups now distinct, as great and even more anomalous than occur in any of 
the preceding extinct genera. 

The Rhynchosaurus of the New Red Sandstone near Shrewsbury manifests 
Ornithic and Chelonian modifications, grafted upon an essentially Lacertian 
type of cranial structure ; no approach even to the form of its extraordinary 
head being made by any other of the extinct members of the Saurian order. 
The vertebrae of the Rhynchosaurus differ from those of existing Lizards, 
Chelonians, and Birds, and combine the biconcave structure with the oblique 
processes and costal articulations of the vertebrae of recent Lizards. 

The -Labyrinthodonts of the same formation exhibit a different but an 
equally remarkable combination of characters, Crocodilian modifications being 
superinduced upon a fundamental organization of the Batrachian type. The 
structure of the teeth in this remarkable family, which is the most complex 
that has hitherto been met with in the whole animal kingdom, is unique in 
the class of Reptiles, and is but partially and comparatively feebly repeated 
in that of Fishes. It is highly probable that the modifications of the loco- 
motive extremities were as peculiar as the dental characters, if we may judge 
from the foot-prints of the so-called Chdrotherium, to which the Labyrintho- 
donts alone have at present an equitable claim. 

Finally, tlie Palceosaurus and other genera of the Magnesian conglome- 
rate, like the so-called Monitors of Thuringia, are lizards which combined a 
thecodont type of dentition, with biconcave vertebrae, having the superadded 
peculiarity of a series of ventricose excavations in the bodies of the vertebrae 
for the spinal chord, instead of a cylindrical canal. 

Below the New Red Sandstone system, notwithstanding that the older de- 
posits, as the coal-measures, have been more thoroughly explored by man than 
any other geological formation, no trace of a vertebrate animal more highly 
organized than a fish, has been detected. 

From this survey it is evident that many races of extinct reptiles have suc- 
ceeded each other as inhabitants of the portion of the earth now forming 
Great Britain ; their abundant remains, through strata of immense thickness, 
show that they existed in great numbers, and probably for many successive 
generations. Their coprolites prove that they fed upon organized beings co- 
existing with them and characterizing the same strata, but now equally ex- 
tinct with their devourers. 

To what natural or secondary cause, it may then be asked, can the succes- 
sive genera and species of Reptiles be attributed ? Does the hypothesis of 
the transmutation of species, by a march of development occasioning a pro- 
gressive ascent in the organic scale, afford any explanation of these surprising 
phenomena? Do the speculations of Maillet, Lamarck and Geoffroy de- 
rive any support or meet with additional disproof from the facts already 
determined in the reptilian department of Palaeontology ? 

A slight survey of organic remains may, indeed, appear to support their 



ON BRITISH FOSSIL REPTILES. 19? 

views of the origin of animated species ; but of no stream of science is it 
more necessary, than of Paleontology, to ' drink deep or taste not*.' 

Of all vertebrated animals, the Reptiles form the class which is least fixed 
in its characters, and is most transitional in its range of modifications ; the 
lowest organized species are hardly distinguishable from fishes, and the highest 
manifest so great an advance in all the important systems of their organism, 
tliat naturalists are not yet agreed as to whether reptiles ought to remain in 
one class or form two. Reptiles are, besides, the only class of vertebrate ani- 
mals in which certain species undergo, after birth, a metamorphosis as singular 
and extreme as in insects. 

If the progressive development of animal organization ever extended be- 
yond the acquisition of the mature characters of the individual, so as to abro- 
gate fixity of species by a transmutation of a lower into a higher organiza- 
tion, some evidence of it ought surely to be obtained from an extensive and 
deep survey of that class of animals which, Avhilst intermediate in organization 
between fishes and mammals, prevailed most on the earth during the long 
periods that intervened between the time when the only vertebrate animals 
were fishes, and the tertiary and modern epochs when mammals have become 
abundant, and have almost superseded reptiles in the herbivorous and carni- 
vorous departments of the economy of nature. 

In accordance with this not unreasonable expectation, the reptiles of the 
Magnesian conglomerate and New Red Sandstone ought to have been organi- 
zed according to the type of the most fish-like perennibranchiate Batrachians ; 
and the Fishes of the older strata, if they tended to a higher stage of deve- 
lopment, ought, upon achieving the passage to the Reptilian class, to have 
entered it at its lowest step. 

It is true, indeed, that the most characteristic Reptilian remains of the 
New Red Sandstone do belong essentially, as by their double occipital con- 
dyle, their vomerine palatal bones and teeth, &c., to the Batrachian order; 
but had the Labyrinthodonts now existed, instead of ranking as the lowest 
members of that order, they would most unquestionably have been esteemed 
the highest. And, as in the existing diversified order of Batrachia, one family f 
represents Fishes, a second | Serpents, a third genus § Chelonians, and a 
fourth II Lizards; so would the now lost Labyrinthodonts have formed Ba- 
trachian representatives of the highest order of Reptiles, viz, the Crocodilians. 
Here, therefore, we find the Batrachian making its first appearance under its 
highest, instead of its lowest or simplest conditions of structure. To use the 
figurative language of the transmutation theory, the Labyrinthodonts are de- 
graded Crocodiles, not elevated Fishes. 

But the hypothetical derivation of reptiles from metamorphosed fishes is 
more directly negatived by the fact, that the Batrachian type is not that 
under which reptiles make their first appearance in the strata which succeed 
the coal-measures. The Monitors of the Thuringian Zechstein are older than 
the Labyrinthodonts of the Keuper ; and among British Reptiles, the theco- 

* The following are the latest terms in which the transmutation-theory has been promul- 
gated, as supported by Pala;ontology : — " The life of animals exhibits a continued series of 
changes, which occupy so short a period that we can generally trace their entire order of 
succession, and perceive the whole chain of their metamorphoses. But the metamorphoses 
of species proceed so slowly with regard to us, that we can neither perceive their origin, their 
maturity, nor their decay; and we ascribe to them a Icind of perpetuity on the earth. A 
slight inspection of the organic relics deposited in the crust of the globe, shows that the 
forms of species, and the whole zoology of our planet, have been constantly changing, and 
that the organic kingdoms, like the siirtace they inhabit, have been graduallydevcloped from 
a simpler state to their present condition." — Dr. Grant's Lectures on Comparative Anatomy, 
Lancet, 1835, p. 1001. 

t Perennibranchiata. + Cccilladx. § Pipa. || Salamandra. 



198 REPORT— 1841. 

dont Lizards of the Magnesian conglomerate have equal claims to a more 
ancient origin. 

The questions, which the unbiased collector of evidence bearing upon the 
fixity or mutability of species has next to resolve respecting these primaeval 
Lizards, are, whether they appeared under the form of the low-organized spe- 
cies which one naturalist classes with Sauria, another with Ophidia, or 
whether they exhibit indications of having emerged, by progressive develop- 
ment of structure, from any lower organized pre-existing group of cold- 
blooded animals ? To these inquiries the Palaeontologist must reply, that 
the thecodont Lizards of the Zechstein and Magnesian conglomerates combine 
well-organized extremities, with teeth implanted in distinct sockets, instead 
of being soldered, as in frogs, to a simple alveolar parapet ; and that there- 
fore if they existed at the present day, they would take rank at the head of 
the Lacertian order, and not among the families most nearly allied to the in- 
ferior reptiles. Neither are the modifications of the skeleton of the Rhyn- 
chosaur from the New Red Sandstone such as indicated that singular Lacer- 
tian to have been derived from the Ophidian or Batrachian orders ; but, on 
the contrary, they connect it more closely than any known recent species, 
with Chelonia and Birds. 

The nearest approximation to the organization of fishes is made by the 
Ichthyosaurus, an extinct genus which appears to have been introduced into 
.the ancient seas subsequent to the deposition of the strata inclosing the re- 
mains of the thecodont Lizards. The ichthyic characters of this genus of ma- 
rine Saurians are not of a very important kind, being limited, like the modifica- 
tions of the mammalian type in Whales, to a relationship with locomotion in 
water, while all the modifications of the skeleton which are connected with 
the respiratory, digestive or generative functions, are conformable with the 
highest or Saurian type of reptiles ; such as the cranial anatomy, the large 
size of the intermaxillary bones excepted, — the dental structure, which cor- 
responds with that of the posterior teeth in Alligators, — the articulation of 
the neurapophyses to the bodies of the vertebras, — the complicated pectoral 
arch, — the sternum and complete abdominal cincture of ribs*, &c. The circle 
of numerous imbricated sclerotic bones reaches its maximum of development 
in the Ichthyosaurus ; but this is an exaggeration of a structure feebly sha- 
dowed forth in some existing Saurians, and more strongly shown in Birds, 
rather than a repetition of the simple bony sclerotic cup in Fishes. By no 
known forms of fossil animals can we diminisli the wide interval which divides 
the most sauroid of Fishes from an Ichthyosaurus. 

This most extraordinary Reptile is a singular compound in which Ichthyic, 
Cetacean, and Ornithic characters are engrafted upon an essentially Saurian 
type of structure. The Ichthyosaurus is, therefore, just such a form of animal 
as might be expected, were specific forms unstable, to demonstrate a mutation 
of characters or some tendency towards a progressive development into a 
higher and more consistent type of organization. Nor is the field for testing 
the transmutation theory less ample than the subject is favourable. We have 
the opportunity of tracing the Ichthyosauri, generation after generation, 
through the whole of the immense series of strata which intervene between the 
new red sandstone and the tertiary deposits. Not only, however, is the ge- 
neric type strictly adhered to, but the very species, which made its first abrupt 
appearance in the lowest of the oolitic series, maintains its characters un- 
changed and recognizable in the highest of the secondary strata. In the chalk 
formations, for example, the genus Ichthyosaurus quits the stage of existence 

* This structure proves that the mode of generation of the Ichthyosaurus must have re- 
sembled that of the Crocodile, and not that of the Batrachians or Fishes. 



ON BRITISH FOSSIL REPTILES. 199 

as suddenly as it entered it in the lias, and with every appreciable osteological 
character unchanged. 

Of the different species of the Ichthyosaurus, founded upon minor modi- 
fications of the skeleton, several appear contemporaneously in the strata where 
the genus is first introduced ; and those which remain the longest manifest 
as little change of specific as of generic characters. There is no evidence 
whatever that one species has succeeded or been the result of the transmuta- 
tion of a former species. The tenuirostral Ichthyosaurus existed at the same 
time, and under the same external influences, as the stronger and shorter jawed 
Ichthyosaurus communis ; just as the tenuirostral Delphinus Gangeticus co- 
exists at present with the short-jawed porpoise. 

If the relative periods of existence of the different Enaliosaurian reptiles 
were not well ascertained, and room were allowed for conjecture as to their 
successive appearance on this planet, it Avould be as easy as seductive to spe- 
culate on the metamorphoses by which their organic framework, influenced 
by varying conditions, during a lapse of ages, might have been gradually 
modified, so as to have successively developed itself from an Ichthyosaur to 
a Plesiosaur, and thence to a Crocodfle. 

We may readily conceive, for example, the fish-like characters of the ver- 
tebral column of the Ichthyosaurus to have been obliterated by a filling-up 
of the intervertebral cavities through ossification of the intermediate elastic 
tissue, and the Plesiosaurian type of vertebra to be thus acquired. The normal 
digits of the fin might be supposed to become strengthened and elongated by 
more frequent reptation on dry land, and thus to cause an atrophy of the 
supernumerary fingers : phalanges of a more saurian figure might have been 
produced by the confluence of a certain number of digital ossicles: the head 
might be shortened by a stunted growth of the intermaxillary bones, and thus 
be reduced to Plesiosaurian proportions. The teeth might become more 
firmly fixed by the shooting of bony walls across their interspaces, as in the 
young Crocodiles. If we now elongate the bodies of the vertebra, reduce 
some twenty pairs of anterior ribs to hatchet-bones, place the fore-paddles at 
a corresponding distance from the head, and the hind-paddles proportionally 
nearer the end of the tail, little more will be required to complete the trans- 
mutation of the Ichthyosaur into the Plesiosaur. 

If next, in adaptation to a gradual change of surrounding circumstances, 
the jaws of the Plesiosaur became lengthened to the proportions of those of 
the tenuirostral Ichthyosaur, but at the expense of the maxillary, instead of 
the intermaxillary bones, preserving the socketed implantation of the teeth ; if, 
to balance the elongation of the jaws the neck at the same time shrank to 
nearly its former Ichthyosaurian proportions, with some slight modifications 
of the Plesiosaurian type of the vertebras ; if a further development and a 
more complete separation of the digits of the fore and hind members were to 
take place, so that they might serve for creeping as well as swimming ; if the 
exposure of the surface to two different media, and of the entire animal to perils 
of land as well as of sea, were to be followed by the ossification of certain 
parts of the skin, and the acquisition, by this change, of a dermal armour, — 
such we might conceive to be the leading steps in the transmutation of the 
Plesiosaur into the Teleosaur. 

And if the three forms of extinct Saurians, whose changes of specific and 
generic characters have thus been speculated on, had actually succeeded each 
otlier in strata successively superimposed in the order in which they have 
here been liypotlietically derived from one another, some colour of probability 
might attach itself to this hypothesis, and there would be ground for search- 
ing more closely into the anatomical and physiological possibilities of such 



200 REPORT — 1841. 

transmutations. Ichthyosaurus, Plesiosaurus and Teleosaurus are, however, 
genera which appeared contemporaneously on the stage of vital existence : 
one neither preceded nor came after the other. How the transmutation theory 
is to be reconciled to these facts is not obvious ; nor to these other, viz. that 
the Teleosaur ceases with the oolite, while the Ichthyosaur and Plesiosaur 
continue to co-exist to the deposition of the chalk, and disappear together 
alike unchanged ; the Ichthyosaur manifesting as little tendency to develop 
itself into a Plesiosaur, as this to degrade itself into the more fish-like modift- 
cation of the Enaliosaurian type. 

If it were urged that the Strejitospo7idylus, or Crocodile with ball-and- 
socket vertebrae, of which the remains occur in later secondary strata, when 
the Teleosaur had ceased to exist, might be a modification of the apparently 
extinct amphiccelian Crocodile, in which the vertebrae had undergone a pro- 
gressive development, analogous to that by which the biconcave joints of the 
vertebrae of the Tadpole are actually converted into the ball-and-socket joints 
of those of the mature Frog, the facts of both geology and anatomy again 
oppose themselves to such an hypothesis : for the remains of the Strepto- 
spondylus occur likewise in the Whitby lias, which is the earliest formation 
characterized by remains of the Teleosaurus ; and the modifications of the 
vertebral structure, by which the Streptospondylus differs from its ancient 
contemporary, and which it retains unaltered throughout the whole series of 
oolitic strata, is no approximation to the ball-and-socket structure of modern 
Crocodiles which first appears in the Mosasaurus and the Eocene Crocodiles, 
but is the very reverse. As reasonably* might we infer that the Teleosaur was 
an intermediate form between the Streptaspondylus and modern Crocodiles, 
and that the anterior ball had first subsided, and a sub-biconcave type of ver- 
tebrae had been produced before the posterior ball, which characterizes the ver- 
tebrae of recent Crocodiles, was finally developed. 

If the present species of animals had resulted from progressive develop- 
ment and transmutation of former species, each class ought now to present 
its typical characters under their highest recognized conditions of organiza- 
tion : but the review of the characters of fossil Reptiles, taken in the present 
Report, proves that this is not the case. 

No reptile now exists which combines a complicated and thecodont den- 
tition with limbs so proportionally large and strong, having such well-de- 
veloped marrow bones, and sustaining the weight of the trunk by synchon- 
drosis or anchylosis to so long and complicated a sacrum, as in the order 
Dinosauria. 

The Megalosaurs and Iguanodons, rejoicing in these undeniably most per- 
fect modifications of the Reptilian type, attained the greatest bulk, and must 
have played the most conspicuous parts, in their respective characters as de- 
vourers of animals and feeders upon vegetables, that this earth has ever wit- 
nessed in oviparous and cold-blooded creatures. They were as superior in 
organization and in bulk to the Crocodiles that preceded them as to those 
which came after them. 

There is not the slightest ground for affirming that the proccelian Gavial of 
the present day is in any respect more highly organized than the opisthocoe- 
lian Gavial of the oldest lias. If the differences of vertebral structure in these 
Crocodilians were contrasted, in reference to their relative approximation to 
the vertebral structure of the higher animals, the resemblance of the ball-and- 
socket joints of the spine of the Streptospondylus to those of certain mam- 
mals would give precedence in organic perfection to the primasval Gavial. 

If, therefore, the extinct species, in which the Reptilian organization cul- 
minated, were on the march of development to a higher type, the Megalo- 



ON BRITISH FOSSIL REPTILES. 201 

saurus ought to have given origin to the carnivorous mammalia, and the 
herbivorous should have been derived from the Iguanodon, But where is the 
trace of such mammalia in the strata immediately succeeding those in which 
we lose sight of the relics of the great Dinosaurian Reptiles ? Or where, in- 
deed, can any mammiferous animal be pointed out whose organization can 
by any ingenuity or licence of conjecture, be derived Avithout violation of all 
known anatomical and physiological principles, from transmutation or pro- 
gressive development of the highest reptiles ? 

If something more than a slight inspection be bestowed upon the organic 
relics deposited in the crust of the globe, we learn that the introduction of 
mammalia on that crust is independent of the appearance of the highest forms 
of Reptiles. The small insectivorous mammals of the lower oolite* are con- 
temporary with the most ancient Dinosaur, and are anterior to the Iguanodon. 

The period when the class of Reptiles flourished under the widest modi- 
fications, in the greatest number and of the highest grade of organization, is 
past ; and, since the extinction of the Dinosaurian order, it has been declining. 
The Reptilia are now in great part superseded by higher classes : Pterodac- 
tyles have given way to Birds ; Megalosaurs and Iguanodons to cai-nivorous 
and herbivorous mammalia ; but the sudden extinction of the one, and the 
abrupt appearance of the other, are alike inexplicable on any known natural 
causes or analogies. 

New species, genera, and families of Reptiles have constantly succeeded 
each other, since the earliest periods in which the remains of this class can 
be discerned ; but the change has been, upon the whole, from the complicated 
to the simple. 

The Batrachian order, which is first indicated by the large and powerful 
Crocodiloid Labyrinthodonts, has dwindled down to the diminutive and de- 
fenceless Anourans and the fish-like Perennibranchians. The Saurian order 
was anciently represented by Reptiles manifesting the Crocodilian grade of 
organization under a rich variety of modifications and with great develop- 
ment of bulk and power : it has now subsided into a swarm of small Lacer- 
tians, headed by so few examples of the higher or loricate species, that it is 
no marvel such relics of a once predominating group should have found a 
humble place in Linnaus's Catalogue of Nature as coordinate members of 
the genus Lacerta. 

Nevertheless some general analogies may be traced between the phaeno- 
mena of the succession of Reptiles as a class, and those observed in the de- 
velopment of an individual reptile from the ovum. Thus the Embryonic 
structure of the vertebrae of the existing Crocodiles accords with the bicon- 
cave type ; and this is exchanged, in the development of the individual as in 
the succession of species, for the ball-and-socket structure as the latest con- 
dition. 

The almost universal prevalence of the more or less biconcave structure of 
the vertebrae of the earlier reptiles thus establishes a most interesting analogy 
between them and the earlier stages of growth of existing reptiles. 

A similar analogy has been pointed out by M. Agassiz, between the hete- 
rocercal fishes, which exclusively prevail in the oldest fossiliferous strata, 
and the embryos of existing homucercal fishes, which seem to pass through 
the heterocercal stage. 

The superior number of loricate Reptiles, and the more complete develop- 
ment of the dermal armour in the Crocodilian genera Steneosaurus, Teleo- 

* For the proof of the often doubted mammalian character of the Thylacothcrium and 
Phascnlotherium of the Stonestield slate, the reader is referred to the Memoirs in the Sixth 
Volume of the Second Scries of the Geological Transactions, pp. 47-58. 



202 REPORT— 1841. 

saurus, Goniopholis, &c., of the Oolitic and Wealden strata, corresponds 
with the prevalence of the well-mailed Ganoid order of fishes in the same 
formations. 

The fossil reptiles, like the fossil fishes, approximate nearest to existing 
species in the tertiary deposits, and diiFer from them most widely in strata 
whose antiquity is highest. 

Not a single species of fossil reptile now lives on the present surface of 
the globe. 

The characters of modern genera cannot be applied to any species of fossil 
reptile in strata lower than the tertiary formations. 

No reptile, with vertebrae articulated like those of existing species, has 
been discovered below the chalk. 

Some doubt may be entertained as to whether the Ichthyosaurus communis 
did not leave its remains in both oolitic and cretaceous formations, but with 
this exception no single species of fossil reptile has yet been found that is 
common to any two great geological formations. 

The evidence acquired by the researches which are detailed in the body 
of this Report, permits of no other conclusion than that the diff'erent species 
of Reptiles were suddenly introduced upon the earth's surface, although it 
demonstrates a certain systematic regularity in the order of their appearance. 
Upon the whole thej' make a progressive approach to the organization of the 
existing species, yet not by an uninterrupted succession of approximating 
steps. Neither is the progression one of ascent, for the Reptiles have not 
begun by the perennibranchiate type of organization, by which, at the present 
day, they most closely approach fishes ; nor have they terminated at the op- 
posite extreme, viz. at the Dinosaurian order, where we know that the Rep- 
tilian type of structure made the nearest approach to Mammals. 

Thus, though a general progression may be discerned, the interruptions 
and faults, to use a geological phrase, negative the notion that the progression 
has been the result of self-developing energies adequate to a transmutation 
of specific characters ; but, on the contrary, support the conclusion that the 
modifications of osteological structure which characterize the extinct Rep- 
tiles, were originally impressed upon them at their creation, and have been 
neither derived from improvement of a lower, nor lost by progi'essive develop- 
ment into a higher type. 

The general progressive approximation of the animal kingdom to its pre- 
sent condition has been, doubtless, accompanied by a corresponding progress 
of the inorganic world ; and thus, the diff'erences which comparative anatomy 
demonstrates to have existed between the vertebrated inhabitants of the 
secondary epochs of the geological history of the earth, and the tertiary and 
present periods, form legitimate grounds for speculation, not only on the 
essential nature and causes of those diflierences, but upon the progressive 
changes to which our planet and its atmosphere may have been subject. For 
whether there had been grounds for regarding the organic phaenomena of pri- 
maeval times as earlier stages in the progressive development and transmuta- 
tion of species, or whether, as the closest investigation of these phaenomena 
seems to demonstrate, they have been the result of expressly created and suc- 
cessively introduced species, — they naturally lead the physiologist to specu- 
late on the varying conditions of the surrounding media to which such organic 
differences may have related. 

Now Reptiles mainly and essentially diflFer from Birds and Mammals in 
the less active performance of the respiratory function, and in a lower and 
simpler structure of the lungs and heart, whereby they become, so to say, 



ON BRITISH FOSSIL REPTILES. 203 

less dependent on the atmosphere, or oxygen, for existence. From their ex- 
traordinary prevalence in the secondary periods, under varied modifications 
of size and structure, severally adapting them to the performance of those 
tasks in the economy of organic nature which are now assigned to the warm- 
blooded and quick-breathing classes, the physiologist is led to conjecture that 
the atmosphere had not undergone those changes, which the consolidation and 
concentration of certain of its elements in subsequent additions to the earth's 
crust may have occasioned, during the long lapse of ages during which the 
extinction of so large a proportion of the Reptilian class took place. And if 
the chemist, by wide and extended views of his science in relation to geology 
and mineralogy, should demonstrate, as the botanist, from considerations of 
the peculiar features of the extinct Flora has been led to suspect, that the at- 
mosphere of this globe formerly contained more carbon and less oxygen than 
at present, then the anatomist might, a priori, have concluded that the highest 
classes of animals suited to the respiration of such a medium must have been 
the cold-blooded fishes and reptiles. 

And besides the probability of such a condition of the zoological series 
being connected with the chemical modifications of the air, the terrestrial 
Reptiles, from the inferior energy of their muscular contractions, and still 
more from the greater irritability of the fibres and power of continuing their 
actions, would constitute the highest organized species, best adapted to exist 
under greater atmospheric pressure than operates on the surface of the earth 
at the present time. 

Through such a medium approaching in a corresponding degree to the 
physical properties of water, a cold-blooded animal might even rise above the 
surface and wing its heavy flight, since this would demand less energetic mus- 
cular actions than are now requisite for such a kind of locomotion ; and thus 
we may conceive why the atmosphere of our planet, during the earlier oolitic 
periods, may have been traversed by creatures of no higher organization than 
Saurians. If we may presume to conjecture that atmospheric pressure has 
been diminished by a change in the composition as well as by a diminution 
of the general mass of the air, the beautiful adaptation of the structure of 
birds to a medium thus rendered both lighter and more invigorating, by the 
abstraction of carbon and an increase of oxygen, must be appreciable by 
every physiologist. And it is not without interest to observe, that the period 
when such change would be thus indicated by the first appearance of birds 
in the Wealden strata*, is likewise characterized by the prevalence of those 
Dinosaurian Reptiles which in structure most nearly approach Mammalia, and 
which, in all probability, from their correspondence with Crocodiles in the 
anatomy of the thorax, enjoyed a circulation as complete as that of the Cro- 
codile when breathing freely on dry landf. 

* Foot-prints alone, like those termed ' Ornithichnites,' observed in the New Red Sand- 
stone of Connecticut, are insufficient to support the inference of the possession of the 
highly developed organization of a bird of flight by the creatures which have left them. The 
Uhynchosaur and biped Pterodactyles already warn us how closely the ornithic type may be 
approached without the essential chai-acters of the Saurian being lost. By the Chirotherian 
Ichnolites we learn how closely an animal, in all probability a Batrachian, may resemble a 
pedinianous mammal in the form of its foot-prints. 

The degree in which flying insects can resist noxious gases, which would be quickly fatal to 
the wai-ni-blooded Verteljrates, invalidates the objection to a pi'ogressive change of atmosphere 
having accompanied the prevalence of quick-breathing animals, which might be suggested by 
the Libellutee of the has and by the oolitic Beetles. 

t All existing Reptiles, which have the ribs at the anterior part of the thorax united by 
a head and tubercle to the centrum and neurapophysis of the vertel)rpe, have a heart with 
two distinct ventricles as well as two auricles. The contiguous aortic aiising from the two 
ventricles intercommunicate by an aperture so placed as to be covered by the sigmoid valves 



204 ^ REPORT— 1841. 

The first indications of the warm-blooded classes, it might be anticipated, 
would appear, if introduced into the Reptilian era, under the form of such 
small insectivorous mammals, as are known at the present day to have a lower 
amount of respiration than the rest of the class ; and the earliest discovered 
remains of mammalia, as, for example, those in the Stonesfield oolite, are 
actually the jaws of such species, with which are combined the characters 
of that order, Marsupialia, which is most nearly related to the oviparous Ver- 
tebrata. 

The present speculations are, however, offered with all due diffidence ; the 
collection of the evidence requisite for pursuing them to a semblance even 
of demonstration is only just begun, and they are thrown out with no other 
expectation of utility than as incentives to the chemical considerations of the 
nature and possibilities of such atmospheric changes as may be physiologi- 
cally connected with the variations of organic nature made known by the re- 
searches of the anatomist. 

A too cautious observer would, perhaps, have shrunk from such specula- 
tions, although legitimately suggesting themselves from the necessary rela- 
tions between the organs and media of respiration ; but the sincere and ardent 
searcher after truth, in exploring the dark regions of the past, must feel him- 
self bound to speak of whatever a ray from the intellectual torch may reach, 
even though the features of the object should be but dimly revealed. 

when blood is transmitted equally through them. When the amphibious Crocodile suffers 
an interruption in the pulmonary circulation by continued submersion, the aorta from the 
left ventricle, by the communication above mentioned, receives venous blood from the over- 
charged cavities of the right side of the heart ; but when respiration is in full vigour on dry 
land, an undiluted stream of arterial blood is transmitted through the left aorta to the head 
and anterior extremities. The Dinosaurs, having the same thoracic structure as the Croco- 
diles, may be concluded to have possessed a four-chambered heart ; and, from their superior 
adaptation to terrestrial life, to have enjoyed the function of such a highly-organized centre 
of circulation in a degree more nearly approaching that which now characterizes the warm- 
blooded Vertebrata. 



ERRATA. 

Page 64, 14 lines from bottom, ybr ' Coelospondylian' read ' Amphicoelian.' 

67, 25 lines from top, ./or ' bifurcate' read ' biporcate.' 

88, after the 3rd line from top, insert ' with convexo-concave vertebrae.' 

104, 14 lines from bottom,/or ' Cloeospondylian ' read ' Amphicoehan. 



ON RAILWAY CONSTANTS. 205 



Reports on the Determination of the Mean Value of Railway 

Constants, 



NOTICE. 

The two following Reports, as well as the Report by Dr. Lardner on the 
same subject, already publislied in the Reports of the British Association 
for 1838, have been furnished in compliance with the request of the Com- 
mittee to whom the superintendence of the experiments and the grants of 
money for the purpose of ascertaining the amount of railway constants was 
entrusted by the British Association. 

. The Committee originally appointed in 1837 consisted of Mr. H. Earle, 
Dr. Lardner, Mr. Locke, Mr. Rennie, and Mr. Macneil, to these Mr. Edward 
Woods was subsequently added. 

The engagements of the various members of the Committee prevented 
them from giving that personal and individual attention to the experiments 
which were so highly desirable, and but for the continued and indefatigable 
exertions of Dr. Lardner, Mr. H. Earle, and Mr. E. Woods, the object of the 
Association could never have been carried out. 

Of the two following Reports, the one is in continuation and conclusion of 
that which has already appeared by Dr. Lardner ; the other is a separate 
and independent Report by Mr. E. Woods, referring partly to the same and 
partly to a great number of additional experiments. 

The Report of Mr. E. Woods, while it agrees in many important particulars, 
differs in others from the Reports of Dr. Lardner, and, when viewed as a 
whole, is somewhat different both in its structure and in the manner in which 
the conclusions are arrived at, deduced, and reasoned upon. 

Under these circumstances, the Committee of the Mechanical Section of 
the British Association at Plymouth were of opinion that the objects of the 
Association would be best fulfilled by the publication of both ; the results in 
which both agree will be looked upon as extremely valuable both by the 
theoretical and practical man, while those in which they differ will form sub- 
jects of great interest for future inquiry. 



Second and concluding Report on the Determination, of the Mean 
Value of Raihvay Constants. By Dionysius Lardner, LL.D., 
F.R.S., &c. 

By reference to the former part of this Report, it will be perceived that among 
the points which remained for furtlier experimental inquiry the principal were 
the following : 

1. Whether the presence of the engine and tender in front of the train has 
any effect in rendering the resistance to the progressive motion of the train, 
arising from friction or atmospheric resistance, or both of these combined, 
less than it would be if the train were moved forward with the front of the 
foremost coach presented directly to the air. 

2. Whether the ybrm of the front of the train produces any sensible effect 
on the resistance, or whether any advantage can be gained by the adoption 
of a pointed front like the bow of a ship. 

3. Whether, in moving down an inclined plane by gravity, the resistance 



206 REPORT— 1841. 

of the air acting against the foremost carriage has a greater effect in throw- 
ing the succeeding carriages out of square than it would have if the train 
were preceded by the engine and tender. 

4. In what manner the resistance would be modified by increasing the 
length and weight of the train. 

These questions have severally arisen out of objections urged against the 
experiments detailed in the former part of this Report, and against the vali- 
dity of the consequences therein deduced from them, by Mr. I. K. Brunei, 
the engineer of the Great Western Railway, in a report addi-essed to the 
directors of that company. 

Although, from the general experience of the writer of this Report and of 
the other members of the Committee, it appeared that none of these various 
objections had much weight, it was considered right to bring them to the 
immediate test of experiment. 

It was first objected, " That the circumstances under which the experiments 
" were performed were not really, though they were apparently, similar to 
" those of any ordinary train in motion ; that the carriages in these experi- 
" ments were sent with the square end foremost to meet and receive the full 
" resistance due to their surface, which is totally different from the case in 
" which the engine precedes them." The engine in front, it was stated, would 
act as a cut-air or bow, and thus destroy or diminish the resistance produced 
by the flat front of the carriage moving foremost. 

In order to ascertain the force of this objection, the following experiment 
was made. 

An engine called the "Fury" was reduced as nearly as possible to the 
condition of an ordinary carriage, by detaching from the axles and removing 
from the engine the connecting rods, pistons, working gear, and every mo- 
ving part which could produce any mechanical resistance different from that 
to which an ordinary coach would be subject. Two coaches were also pro- 
cured, and so loaded as to be exactly equal in weight with the engine and 
tender. 

The engine and tender were then placed at the summit of the Sutton in- 
clined plane on the Liverpool and Manchester Railway, which falls 1 in 89, 
for about a mile and a half, and were allowed to descend the plane by their 
gravity ; the time of passing a succession of stakes dividing the plane into 
spaces of 110 yards, was noted. 

The two coaches were next placed at the summit of the plane, and allowed 
in like manner to descend, and the circumstances of their descent observed 
in the same way. 

Sutton Incline Plane. — Is laid Avith 60 lbs. rails, 3 feet bearings, on stone 
blocks: road has been recently relaid : posts are placed 110 yards, or one 
sixteenth of a mile apart : descent from No. to No. 1 1 post is 3*63 feet per 
110 yards =1 in 90*9 : gravitating force is therefore 24*64 lbs. per ton : de- 
scent from No. 11 to No. 20 post is 3'71 feet per 110 yards = 1 in 88'5; gra- 
vitating force is therefore 25*31 lbs. per ton. 

Whiston Incline Plane. — Was laid with 50 lbs. rails, 3 feet bearings, on 
stone blocks, about three years since: posts placed 110 yards, or one six- 
teenth of a mile apart : descent 1 in 96 : gravitating force is therefore 23*33 
lbs. per ton. A section of these planes is given in fig. 1. Plate I. A breeze 
from W.N.W. : a drizzling rain : rails quite wet, and in good order for 
travelling. 

The details of these two experiments were as follows : — 



ON RAILWAY CONSTANTS. 



207 



Experiment with ^^ Fury" and Tender. 

cwts. qrs. lbs. 

"Fuiy" engine 147 3 

Tender 75 

Load 5 



Gross weight ... 227 3 
From a state of rest, down Sutton Incline Plane. 



Yds. 



110 

220 

330 

440 

550 

660 

770 

880 

990 

1100 

1210 

1320 

1430 

1540 

1650 

1760 

1870 

1980 

2090 

2200 

2310 



Times. 



11 1 
59 

12 22 

40 



13 



14 



15 



55 

9 
21-5 
34 
44-5 
55 

5 

14-5 
24 
33 
41-5 
50-5 
58-5 

7 
15 

22-25 
30-5 
38-5 






58 

23 

18 

15 

14 

12-5 

12-5 

10-5 

10-5 

10 

9-5 

9-5 

9 

8-5 

9 

8 

8-5 

8 

7-25 

8-25 

8-0 



Average 
Diffs 



jl2-5 
1 10-5 



} 



9-5 



8-5 



V 8-25 
I 7-75 



Miles 

per 

hour. 



3-88 

9-78 

12-50 

15-00 

16-07 

18-00 

21-43 
22-50 
23-68 
25-00 

26-47 

27-27 

29-03 
28-12 



Yds. 
2420 
2530 
2640 
2750 
2860 
2970 
3080 
3190 
3300 
3410 
3520 
3630 
3740 
3850 
3960 
4070 
4180 
4290 
4400 
4510 
4620 
4710 



Times. 



m s 
15 46-5 
54-5 

3 

11-5 
21 
31 
41-5 
52-5 

4-5 
16-25 
29-75 
44-25 
59 
15 
33 
53 
13-5 
38 

4 
35-5 

21 17 

22 38 



16 



17 



18 



19 



20 






8 
8 

8-5 

8-5 

9-5 

10 

10-5 

11 

12-25 
11-75 
13-5 
14-5 
14-75 
16 
18 
20 
20-5 
24-5 
26 
31-5 
41-5 
81 



Average 
Diffs 



8-5 



1 12-1 



00 



Miles 

per 

hour. 



28-12 

26-47 

23-68 
22-50 
21-43 
20-45 

18-75 

16-66 

15-51 

15-25 

14-06 

12-50 

11-25 

10-97 

9-18 

8-65 

7-14 

6-14 



Experiment with two Coaches. 

Two First Class Carriages, 
cwts. 

Caledonian 116 

Earl of Derby ..... 110 



qrs, 
3 




lbs. 





226 3 
From a state of rest, down Sutton Incline Plane. 





(A 


Times. 




Average 
Diffs. 


Miles 

per 

hour. 


s 


(2 


Times. 


4 


Average 
Diffs. 


Miles 

per 

hour. 


Yds. 

110 
220 
330 
440 
550 
660 
770 




1 
2 

3 
4 

5 
6 
7 


h m s 
9 23 
53-25 

24 15 
33-5 
48-75 

25 2 
14-25 
26 


53-25 

21-75 

18-5 

15-25 

13-25 

12-25 

11-75 




4-22 
10-35 
12-16 
14-75 
16-98 
18-36 
19-14 


Yds. 

880 
990 
1100 
1210 
1320 
1430 
1540 


8 
9 
10 
11 
12 
13 
14 


h m s 

9 25 36-75 
47-5 
57 
26 7 
16 
25 
34 


10-75 
10-75 
9-5 
10 
9 
9 
9 


1 10-75 
1 9-75 

. 9-00 


20-94 
23-08 

25-00 

















208 



REPORT — 1841. 

Table (^Continued'). 



5 


i 


Times. 


(5 


Average 
DifFs. 


Miles 
per 
hour. 






Times. 


5 


Average 
Diffs, 


Miles 
per 
hour. 


Yds. 
1C50 
17fiO 
1870 
1980 
2090 
2200 
2310 
2420 
2530 
2640 
2750 
2860 
2970 
3080 


15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 


h m s 
9 26 42-5 
51-25 
59-25 

27 7-25 
15-75 
23-75 
32 

39-75 
48-25 
57 

28 6-5 
16 
26-5 
37-25 


8-5 
8-75 
8 
8 

8-5 
8 

8-25 
7-75 
8-5 
8-75 
9-5 
9-5 
10-5 
10-75 


1 8-62 
1 8-00 
I 8-25 


26-10 

28-12 

27-26 
27-26 

27-00 

23-68 

21-43 
20-94 


Yds. 
3190 
3300 
3410 
3520 
3630 
3740 
3850 
3960 
4070 
4180 
4290 
4400 
4510 
4577 


29 
30 
31 
32 
33 
34 
35 
36 
37 
38 
39 
40 
41 


h m s 
9 28 49 

29 1 
13-5 
27-25 
42 
58 

30 15-5 
35-25 
57 

31 21-25 
50 

32 22-5 

33 7 

34 40 


11-75 

12 

12-5 

13-75 

14-75 

16 

17-5 

19-75 

21-75 

24-25 

28-75 

32-5 

44-5 

93 




1914 

18-75 

18-00 

16-36 

15-25 

14-06 

12-86 

11-39 

10-35 

9-27 

7-82 

6-92 

5-06 












. 8-33 
1 9-5 























The general results of these two experiments are placed in juxtaposition 
in the following table : — 





Weight. 


Total distance 
run. 


Time of run- 
ning total 
distance. 


Greatest speed. 


Time of descend- 
ing the Sutton 
plane to 20, 


Fury and Tender 
Two Coaches ... 

Difference... 


Tons. 
11-39 
11-33 


Yards. 
4710 
4577 


m s 
11 37 
11 40 


Miles per hour. 
29 
28-12 


m s 
4 29 
4 24 


-06 


133 


3 




5 



It appears, therefore, that the difference in the whole distance run by the 
two coaches and by the engine and tender, amounted to only 133 yards in a 
distance little short of three miles ; and there was only three seconds differ- 
ence in the time which elapsed between the moment of starting and the mo- 
ment of coming to rest. The maximum speed was the same, and the times 
of descending the inclined plane differed by only five seconds. The differ- 
ence, such as it was, was in favour of the coaclies. In fact the differences 
of the numbers in the successive columns are only sucli as woidd take place 
in the same experiment twice repeated with the same coaches. 

As a further experimental test of this point, the engine and tender were 
now placed in front of a train of four coaches, and were allowed to descend 
the plane in the same manner. The engine and tender were tlien removed, 
and replaced by two coaches of equal weight, and the train of six coaches 
was allowed to descend the plane in the same manner. The details of these 
experiments are as follows: — 

Engine, Tender, and four First Class Carriages, viz. 

cwts. qrs. lbs. 

^"'■y, "i 222 3 

Tender J 

Clarence ^ 

Sovereign 1 

Traveller | 

TelegraphJ 



326 3 4 



Gross weight 



S49 2 4 









ON RAILWAY CONSTANTS. 






yoy 




Posts. 


Times. 


Diffs. 


8) • 

2SS 


« 5 

^ o 


t^ 


Posts. 


Times. 


Diffs. 


& . 
2SS 


si 


Q 








< 


cu 


Q 








< 


a. 


Yds, 




h m s 


1 


Yds. 




h m s 














3 30 30 








2640 


24 


3 35 34-5 


8 




28-12 


no 


1 


31 29 


59 




3-81 


2750 


25 




17-5 r 


8-75 


25-72 


220 


2 


54 


25 




9-00 


2860 


26 


52 


330 


3 


32 12 


18 




12-50 


2970 


27 


36 0-5 


8-5 1 
9-25/ 


8-87 


25-34 


440 


4 


• 28 


16 




14-06 


3080 


28 


9-75 


550 


5 


42 


14 




16-07 


3190 


29 


19 


9-25 




24-32 


660 


6 


55 


13 




17-30 


3300 


30 


29-25 


10-25 




21-94 


770 


7 


33 7 


12 




18-75 


3410 


31 


40 


10-75 




20-94 


880 
990 


8 
9 


18 


11 
21-2 1 





20-45 


3520 
3630 


32 

33 


51-25 
37 2 


11-25 1 
10-75 / 


11-00 


20-45 


1100 


10 


39 


10-5 


21-43 


3740 


34 


14 


12 




18-75 


1210 
1320 


11 
12 


48-5 
58 


9-5 1 
9-5 / 


9-5 


23-68 


3850 
3960 


35 
36 


27 

40 


13 l 
13 


13-00 


17-30 


1430 
1540 


13 
14 


34 7 
155 


9 \ 
8-5 J 


8-75 


25-72 


4070 
4180 


37 
38 


54-5 
38 9 


14-5 1 
14-5 J 


14-50 


15-51 


1650 


15 


24 


8-5 \ 
8-5 / 




26-47 


4290 


39 


25 


16 




1406 


1760 


16 


32-5 


8-50 


4400 


40 


42 


17 




13-23 


1870 


17 


40-5 


8 I 
8-25/ 


8-12 


27-68 


4510 


41 


39 0-5 


18-5 




1216 


1980 


18 


48-75 


4620 


42 


20 


19-5 . 




11-54 


2090 


19 


56 


7-251 
7-5 


7-37 


30-50 


4730 


43 


43 


23 





9-78 


2200 


20 


35 3-5 


4840 


44 


40 11 


28 





8-04 


2310 


21 


11-25 


7-751 






4950 


45 


50 


39 




5-78 


2420 


22 


19 


7-75 [ 


7-67 


29-34 


5060 


46 


42 11 


81 




2-78 


2530 


23 


26-5 


7-5 J 






5068 




39 


28 







Six First Class I ^yf^^ ' 

Carriages, viz. j ^^^^ 

° L Clarence 

Gross weight 



cwts. 


qrs. 


lbs. 




cwts. 


qrs. 


lbs. 


93 





24. 


Sovereign 


. 90 


2 


24 


91 


1 


24- 


Traveller 


. 91 


2 


24 


88 


3 


24 


Telegraph 


. 93 


1 


24 


• 


549 


cwts. 


2qrs. 4 lbs. 













From 


a state of rest, down Sutton Incline Plane. 














?n.r 


c 












M 3 


(A 


Posts. 


Times. 


Diffs. 


2Se 


^ o 

— J3 




Vi 


Times. 


Diffs. 


2!c 


.2 o 

■- JS 


P. 








l« 




P 


(2 






j;5 
< 




Yds. 




h m s 








Yds. 




h m s 














12 5 30 








2640 24 


12 10 28-5 


8-25 1 
8 / 


8-12 


27-68 


110 


1 


6 26 


56 




4-02 


27501 25 


36-5 


220 


2 


50 


24 




9-37 


2860 


26 


45-5 


9 1 






330 


3 


7 8-5 


18-5 




12-16 


2970 


27 


54-5 


9 I 


9-00 


25-00 


440 


4 


25 


16-5 




1.3-63 


3080 


28 


11 3-5 


9 






550 


5 


38-5 


13-5 




16-66 


3190 


29 


13 


9-5 




23-68 


660 


6 


51-5 


13 




17-30 


3300 


30 


23 


10 




22-50 


770 


7 


8 3 


11-5 




19-56 


3410 31 


35-5 


12-5 \ 

8-5 f 


10-5 


21-43 


880 


8 


14 


11 




20-45 


3520 32 


44 


990 


9 


24-25 


10-251 
10-25 J 


10-25 


21-94 


3630 33 


55 


11 




20-45 


1100 


10 


34-5 


37401 34 


12 7 


12 




18-75 


1210 


11 


44 


9-5 




23-68 


3850 35 


20 


13 




17-30 


1320 


12 


53 


9 1 


9-00 


25-00 


3960, 36 


33-25 


13-25 




16-98 


1430 


13 


9 2 


9 J 


4070 37 


48 


14-75 




15-25 


1540 


14 


10-25 


8-251 






4180 38 


13 3 


15 




15-00 


1650 


15 


19 


8-75; 


8-50 


2647 


42901 39 


19-5 


16-5 




13-63 


1760 


16 


27 


8 I 


8-00 


•38-12 


4400 40 


38-5 


19 




11-84 


1870 


17 


35 


8 r 


4510 41 


59 


20-5 




10-97 


1980 


18 


43 


8 1 


7-75 


2902 


4020 42 


14 23-5 


24-5 




9-18 


2090 


19 


50-5 


7-5 / 


4730 43 


54-5 


31 




7-26 


2200 


20 


58 


7-5 \ 






4840 44 


15 51 


56-5 




3-98 


2310 


21 


10 5 


7 J 


7-25 


31 03 


4850, ... 


16 18 








2420 


22 


13 


8 "1 


















2530 


23 


20-25 


7-25; 


7-62 


29-5 














U 


m. 








P 















210 



REPORT — 1841. 



Transverse sections of the engine and the coaches are given in figs. 2 
and 3. Plate I. 

The general results of these experiments are here shown in juxtaposition : — ■ 





Weight. 


Total 
distance. 


Time of 

running total 

distance. 


Greatest 
speed. 


Time of 

descending 

Sutton Plane. 


Fury, tender, and" 
four coaches... ' 
Six coaches 


Tons. 

27-45 
27-45 


Yards. 
5068 
4850 


m s 
12 9 
10 48 


Miles per hour. 
30-5 
31 


m s 
4 33 
4 28 


Difference 




218 


1 21 




5 



It is evident from these results, independently of other experiments which 
will be presently stated, that the form of the front, whether flat or sharp, has 
no observable effect on the resistance; and that whether the engine and 
tender be in front, or two carriages of the same weight, the motion of the 
train and the resistance to its motion will be exactly the same. 

The form of a boat or beak having been given to some of the engines on 
one of the lines of railway, and the advantages attending such a form in 
diminishing the resistance having much insisted on, it was determined to 
ascertain its effect by direct experiment. 

For this purpose a sharp end was constructed to be attached in front of 
the foremost carriage, consisting of two boards equal in height to the body 
of the carriage, and which being attached to each corner, were united in 
front at an angle, the vertex of the angle being five feet six inches before 
the flat front of the carriage, and the base of the angle being six feet six 
inches, corresponding with the width of the carriage. Thus, instead of pre- 
senting a flat surface to the air, the carriage having this apparatus attached 
would present a wedge to it, which would have the effect of a cut-air. 

This contrivance was first tried with a single coach, which, having it 
attached in front, was moved as before down the Sutton Plane ; and the cir- 
cumstances of the motion having been observed and recorded, the wedge 
was removed, and the coach again moved down the plane with its flat end 
presented to the air. The following are the results of these experi- 
ments : — 





Weight. 


Total 
distance run. 


Time of 

running total 

distance. 


Greatest 
velocity. 


Time of de- 
scending Sutton 
Plane 1 in 89. 


Coach with point-" 
ed front 

Coach with flat 
front 

Difference 


Tons. 
5-35 

5-35 


Yards. 
3975 

3905 


m s 

11 
11 


Miles per hour. 

24-3 
23-7 


m s 
5 35 

4 45 




70 






50 



This result shows that the form of the front produced no effect on the 
resistance. 

It was determined to remove all possible doubt on this point by varying 
the circumstances of the experiment. A train of eight coaches was accord- 
ingly prepared and brought to the series of inclined planes at Madeley on the 
Grand Junction Railway, the section and curves of which have been de- 
scribed in the fii'st part of this Report. This train was first moved down the 



ON RAILWAY CONSTANTS. 



211 



planes with the pointed end attached, and afterwards without that appendage. 
The details of these two experiments were as follows : — 

July 11th, 1839. — Experiment No. I. 
Eight Second Class Carriages, No. 12, 35, 5, 22, 9, 29, 30, 20. 

tons. cwts. qrs. 

Weight of Carriages and Load , ... 40 
Ten Passengers 15 



Gross weight ... 40 15 
Pointed end placed in front. 

Initial velocity 23'71 miles per hour, down JVIadeley Plane. 



Dist. 




Times. 


Diffs. 


Speed. 


Dist. 


Ph 


Times. 


Diffs, 


Speed. 


Yards. 




h m s 








Yards. 




1 m s 










61 


8 27 36-5 










21 


8 33 18-5 


8-5 


?4-25 


23-89 




60 


46-5 


10 








20 


27 


8-5 








59 


55-75 


9-25 








19 


36 


9 









58 
57 


28 4-25 
13 


8-5 
8-75 


36-5 


22-41 


4000 


18 
17 


44-75 
53-25 


8-75 
8-5 


34-75 


23-54 




56 
55 


22 

30-25 


9 
8-25 








16 
15 


34 2 
10 


8-75 
8 








54 


39 


8-75 








14 
13 


19 


Q 








53 


47-5 


8-5 


34-5 


23-71 




27 


if 

8 


33-75 


24-24 


500 


52 


56 


8-5 






4500 


12 


36 


9 








51 


29 5 


9 








11 


44 


8 








50 
49 


13 
22 


8 
9 


34-5 


23-71 




10 
9 


53-25 
33 1-75 


9-25 

8-5 


34-75 


23-54 




48 


30 


8 








8 


10 


8-25 






1000 


47 


39 


9 






5000 


7 


18 


8 








46 


47-5 


8-5 








6 
5 


27 
35-25 


9 








45 


56-25 


8-75 


34-25 


23-89 




8-25 


33-5 


24-42 


1500 


44 
43 
42 
41 


30 4-25 
13-25 
21-75 
30 


8 
9 

8-5 
8-25 


33-75 


24-24 


5500 


4 
3 
2 

1 


44 

52-75 
36 1 
9 


8-75 
8-75 
8-25 
8 


33-75 


24-24 


2000 


40 
39 
38 
37 


38-5 
47-25 
55-25 
31 3 


8-5 
8-75 
8 
7-75 


33 


24-79 


6000 




1 
2 
3 


17-75 
26 
34-5 
43 


8-75 
8-25 
8-5 
8-5 


34 


24-06 




36 
35 
34 
33 


12-25 
20-25 

37" 


9-25 

8 

8-25 

8-5 


34 


2406 




4 
5 
6 

7 


52 

37 
9-25 

18 


9 

8 
9-25 

8-75 


35 


23-37 


2500 


32 
31 
30 
29 


46 

54 

32 2 

10 


9 
8 
8 
8 


33 


24-79 


6500 


8 

9 

10 

11 


27-5 
36-5 
46 
55-5 


9-5 
9 

9-5 
9-5 


37-5 


21-81 


3000 


28 
27 
26 
25 


18-25 

35-25 
44-25 


8-25 
8-5 
8-5 
9 


34-25 


23-89 


7000 


12 
13 
14 
15 


38 4-5 
14 
23-5 
33 


9 

9-5 
9-5 
9-5 


37-5 


21-81 


350C 


24 
23 
22 


53 
'33 1-25 
10 


8-75 
8-25 
8-75 








16 
17 


42-5 
52-5 


9-5 
100 







p2 



212 



REPORT — 1841, 



Experiment No. I. (contimiecC). 



1 
Dist. 


1 


Times, 


Diffs. 


Speed. 


Dist. 


1 


Times. 


Diffs. 


Speed. 


Yards. 




h m s 








Yards 




h m s 








750fl 


18 


8 39 1-75 


9-25 








50 


8 44 26 


10-5 








19 


11-5 


9-75 


38-5 


21-25 




51 


36-5 


10-5 


41-5 


19-71 




20 


21-25 


9-75 








52 


47-5 


11 








21 


31 


9-75 






11,000 


53 


58 


10-5 








22 


41 


10 








54 


45 8-25 


10-25 






8000 


23 


51 


10 


39-5 


20-71 


• 


55 


19 


10-75 


42-5 


19-25 




24 


40 075 


9-75 








56 


29-5 


10-5 








25 


10-5 


9-75 




1 


57 


40-5 


11 








26 


20-5 


10 






11,500 


58 


51-75 


11-25 








27 


30-25 


9-75 


39-25 


20-84 




59 


46 2 


10-25 


43 


19-02 


8500 


28 


40 


9-75 








60 


13-25 


11-25 








29 


50-25 


10-25 








61 


24-5 


11-25 








30 


41 0-25 


10 








62 


35-75 


11-25 








31 


10 


9-75 


39-75 


20-58 


12,000 


63 


47-5 


11-75 


45-5 


17-98 




32 


20-5 


10-5 








64 


59-25 


11-75 






9000 


33 


30-5 


10 








65 


47 11 


11-75 








34 


41 


10-5 








66 


23 


12 








35 


51-25 


10-25 


41-25 


19-86 




67 


35 


12 


47-5 


17-22 




36 


42 1-25 


10 






12,500 


68 


47-25 


12-25 








37 


11-25 


10 








69 


59-25 


12 






9500 


38 


21-75 


10-5 








70 


48 12-25 


13 








39 


32-25 


10-5 


41 


19-95 




71 


24-5 


12-25 


49-5 


16-53 




40 


42-5 


10-25 








72 


37-75 


13-25 








41 


53-25 


10-75 






13,000 


73 


51-25 


13-5 








42 


43 3 


9-75 








74 


49 4 


12-75 






10,000 


43 


13-25 


10-25 


41 


19-95 




75 


... 


13-25 


52-75 


15-51 




44 


23-75 


10-5 








76 


31 


13-75 








45 


34 


10-25 








77 


44-75 


13-75 




14-87 




46 


44-75 


10-75 






13,500 


78 


58-5 


13-75 








47 


55 


10-25 


41-75 


19-60 


14,411 




54 24-5 






* 


10,500 


48 


44 5-25 


10-25 


















49 


15-5 


10-25 



















Breeze down the Plane. 
* Stopped. 



ON RAILWAY CONSTANTS. 



213 



July 11th, 1839. — Experiment No. II. 

Eight Second Class Carriages as before. • 

tons. cwts. qrs. 
Weight of Carriage and Load .... 40 
Ten Passengers 15 



Gross weight 



. 40 15 
Pointed end taken off. 



From 


initial velocity 23*37 miles 


per hour, 


down Madeley Plane. 




Dist. 


c2 


Times. 


Diffs. 


Speed. 


Dist. 


1 


Times. 


Diffs. 


Speed. 


Yards. 


61 


h m s 
9 37 43 








Yards. 


18 


h m s 
9 43 14-25 


7-75 








60 


53-5 


10-5 






4000 


17 


22-25 


8 


31 


26-39 





59 
58 
57 


38 3 
12-5 
21-25 


9-5 
9-5 

8-75 


38-25 


21-39 




16 
15 
14 


30-25 

38 

46-25 


8 

7-75 

8-25 








56 


30 


8-75 








13 




7-75 


31-75 


25-77 




55 
54 
53 


38 
46 
53-25 


8 
8 
7-25 


32 


25-57 


4500 


12 
11 
10 


44 2 
9-75 
18 


8 

7-75 

8-25 






500 


52 


39 


6-75 








9 


25-75 


7-75 


31-75 


25-77 




51 

50 
49 


15" 
22-5 


7-5 
7-5 

7-5 


29-25 


27-97 


5000 


8 
7 
6 


33-5 

41-25 

49-5 


7-75 
7-75 
8-25 








48 


29-5 


7 








5 


57 


7-5 


31-25 


26-18 


1000 


47 


36-5 


7 








4 
3 
2 




8 
8 
7-5 








46 
45 


44-25 
51-5 


7-75 
7-25 


29 


28-21 


5500 


45 5 
13 
20-5 








44 


58-5 


7 








1 


28-25 


7-75 


31-25 


26-18 


1500 


43 
42 


40 5-75 
13-25 


7-25 
7-5 









■1 


36 


7-75 

8 
8 , 








41 


20-5 


7-25 


29 


28-21 




1 
2 


44 
52 








40 


27-75 


7-25 






6000 


3 


46 


8 


31-75 


25-76 


2000 


39 
38 
37 


35-25 

43 

50-25 


7-5 

7-75 

7-25 


29-75 


27-50 




4 
5 
6 


7-75 
16 
24 


7-75 

8-25 
8 








36 


57-25 


7 








7 


33 


9 


33 


24-79 




35 
34 


41 4-5 
12 


7-25 
7-5 






6500 


8 


41 


8 
9 

8-5 








33 


19-25 


7-25 


29 


28-21 




9 
10 


50 

58-5 






2500 


32 
31 


27 
34-5 


7-75 
7-5 








11 


47 7 


8-5 


34 


24-06 




30 
29 


42 
49-25 


7-5 
7-25 


30 


27-27 


7000 


12 
13 
14 


15-5 
24-5 
33 


8-5 

9 

8-5 








28 


57 


7-75 








15 


42 


9 


35 


23-37 


3000 


27 


42 4 


7 




















26 


12-25 


8-25 








16 


51-25 


9-25 








25 


19-75 


7-5 


30-5 


26-82 


7500 


17 
18 


48 0-25 


9 

8-75 








24 


27-5 


7-75 








19 


is' 


9 


36 


22-73 


3500 


23 
22 


35 
43 


7-5 

8 








20 


27-25 


9-25 








21 


51-25 


8-27 


31-5 


25-97 




21 
22 


36-5 

46 

55-5 


9-25 
9-5 








20 


58-5 


7-25 






8000 


23 


9-5 


37-5 


21-81 




19 


43 6-5 


8 



















214 



REPORT — 1841. 









Experiment No 


II. (continued). 








Dist. 




Times. 


Diffs. 


Speed. 


Dist. 


J2 


Times. 


Diffs. 


Speed. 


Yards. 




h m s 








Yards. 




h m s 










24 


9 49 4-25 


8-75 








55 


9 54 19 


10-75 


42-5 


19-25 




25 
26 
27 


14-5 
24-5 
31-5 


10-25 
10 

7 


36 


22-73 


11,500 


56 
57 
58 


29-75 
40-5 

52 


10-75 
10-75 
11-5 






8500 


28 


43 


11-5 








59 


55 2-5 


10-5 


43-5 


18-81 




29 
30 
31 


52-75 
50 2-5 
12 


9-75 
9-75 
9-5 


40-5 


20-20 




60 
61 
62 


13-75 
25-25 
36-5 


11-25 

11-5 

11-25 








32 


22-25 


10-25 






12,000 


63 


48-75 


12-25 


46-25 


17-69 


9000 


33 
34 
35 


32-25 
42-25 
52-5 


10 
10 
10-25 


40-5 


20-20 




64 
65 
66 


56 0-5 
12-5 
34-5 


11-75 

12 

12 








36 


51 2 


9-5 








67 


37 


12-5 


48-25 


16-96 


9500 


37 
38 
39 


12-25 
22-25 
32-25 


10-25 

10 

10 


39-75 


20-58 


12,500 


68 
69 
70 


50 
57 2-5 
15 


13 

12-5 

12-5 








40 


42-6 


10-25 








71 


28-5 


13-5 


51*5 


15-89 




41 


52-75 


10-25 








79, 


41-75 


13-^5 






10,000 


42 
43 


52 3 
13-25 


10-25 
10-25 


41 


19-95 


13,000 


73 

74 


55-5 
58 9 


13-75 
13-5 








44 


23-25 


10 








75 


... 


13-5 


54 


15-15 




45 

46 
47 


34 

44-25 

54-5 


10-75 
10-25 
10-25 


41-25 


19-83 


13,500 


76 

77 
78 


36-5 
51 
59 5 


14 

14-5 

14 






10,500 


48 


53 5 


10-5 






13,598 




19-5 


14-5 


57 


14-35 




49 


15 


10 






13,785 




51-5 




* 






50 


26 


11 






13,915 




10 16 










51 


36-5 


10-5 


42 


19-48 


14,242 




1 53-5 










52 


47-25 


10-75 






14,331 




3 22 








11,000 


53 
54 


58 
54 8-25 


10-75 
10-25 



















Breeze down the Plane. 

* Stopped. 



The general results of these two experiments are here exhibited in juxta- 
position. 





so 


1) 

i . 


bo 

c . 

.-H <U 

C o 

c c 

si 


T3 

a. 
'a 


e 
o 

'5 


O 


Cm 

o 

« a 

a. 
w 


.S b^ 

1' 


bO . 

a.s 


Time of moving 
round 1 in 330. 


Train with point- ' 
edendforemost. ' 


Tons. 

40-75 


Yards. 

14,411 


m s 
26 48 


MUes 
per hr. 

23-70 


Miles 
per hr. 

24- 


Miles 
per hr. 

19-25 


Miles: 
per hr. 

14-87 


m s 

8 41 


m s 
8 60 


ra s 
4 50 


Same train in its' 
ordinary state. 


40-75 


14,331 


25 39 


23-37 


26-18 


19-25 


14-35 


7 53 


9 32 


4 57 


Difference 




80 


1 9 


0-33 


2-18 




0-52 


48 


42 


7 



ON RAILWAY CONSTANTS. 



215 



It appears, therefore, that the distance run with the wedge foremost dif- 
fered only 80 yards in a distance of about eight miles from that through which 
the same train ran with its flat front. This and the other differences indi- 
cated in the table are evidently such only as would take place Avith the same 
experiment twice repeated with the same carriages. 

With a view to ascertain how far mere magnitude of frontage, indepen- 
dently of the general magnitude of the train, is productive of resistance, the 
front of a coach was enlarged by boards extending from either side to a di- 
stance of about twenty inches, adding about twenty-four square feet to the 
front surface, and forming a sort of wings in front of the carriage, but no 
corresponding Avidth being given to any other part of the carriage. The 
coach thus prepared was placed at the summit of the Sutton plane, and al- 
lowed to descend from a state of rest. It was then brought back to the sum- 
mit and the wings removed, and was allowed to descend in its ordinary 
state. The result of these two experiments was as follows : — 





Weight. 


Total 

distance 

run. 


Time of 
running 

that 
distance. 


Greatest 
speed. 


Time of 

moving down 

Sutton Plane 

1-89. 


Coach with en- "1 
larged front. J 

Coach with or-l 
dinary front. J 


Tons. 
5-35 

535 


Yards. 

3,139 

3,289 


m s 
9 10 

9 2 


m. per h. 
19-15 

21-45 


m s 
5 31 

4 15 


Difference 




150 


8 


2-30 


I 16 



From which it was inferred, that mere width of frontage, apart from the 
general increase of magnitude, was not productive of any considerable prac- 
tical effect in increasing the resistance. 

A strong impression existed in the minds of some engineers and scientific 
men, to whom the results of these experiments was communicated while 
they were in progress, that the shape of the hinder part of the train might 
iiave an effect upon tlie resistance. It was supposed that in very rapid mo- 
tion a tendency to a vacuum would be produced behind the train, and that 
a corresponding atmospheric resistance, due to this partial vacuum, would 
be produced in front ; that, consequently, if the square shape was removed 
from the hinder part, less resistance would be found. Although no great 
weight was attached to this, it was determined, nevertheless, to submit it to 
a trial, and with that view a train of three carriages was placed at the sum- 
mit of the Sutton plane, falling -^, and allowed to descend by gravity in 
their ordinary state. They were next alloAved to descend, having the pointed 
end behind ; they next descended with the pointed end before : and, lastly, 
they were once more allowed to descend without the pointed end. The result 
of these four experiments is given in the following table. (See Table, p. 216.) 

In the third column is expressed the entire distance run, in yards ; in the 
fourth column is the time of going that distance ; in the fifth column is the 
speed acquired in descending the Sutton plane ; in the sixth column the time 
of descending that plane; in the seventh column the time of moving a di- 
stance of 2\ miles from the time of starting ; and in the last column, the 
time of moving from the twelfth to the twenty-eighth stake, throughout 
which, tiie motion being tolerably rapid, the effect of the air might be ex- 
pected to be greatest. 

It is evident, from these experiments, that no modification of the resist- 



216 



REPORT 1841. 



auce is produced by the form of either end of the train, at least within any 
practical limits, to which the variation oT that form can be subject. 

In order to ascertain whether the open spaces between the successive car- 
riages forming the train had any effect upon the resistance, hooks were at- 
tached to the edges of the ends of the several coaches, by means of which 
canvas was stretched from coach to coach so as to cover in those open 
spaces, and convert the train into a single unbroken column. The train thus 
prepared was the same train of eight coaches used in the former experiments, 
and the following are the details of the experiments made on the Madeley 
planes. 





Weight. 


Total 

distance 

run. 


Time of 
running 

total 
distance. 


Greatest 
speed. 


Time of 

moving down 

Sutton Plane 

1-89. 


Time of 
moving 
2^ miles. 


Time from 
stake 12 

to 
stake 28. 


Three coaches.with 1 

flat front and end. J 
Same,with pointed ' 

end 

Same, with pointed 

front 

Same, with flat 

front and end.... 


Tons. 

14-8 
14-8 
14-8 
14-8 


Yards. 
5,209 

5,350 

5,576 

5,518 


in s 

13 50 
13 45 
13 1 
13 25 


m. per h. 

32-14 
31-03 
3214 
32-14 


m s 

4 28 
4 25 
4 23 
4 22 


m s 
7 54 

7 50 

7 30 

7 32 


m s 
2 9 

2 9 

2 5 

2 6 



July 11th, 1839. 



Eight Second Class Carriages as before, the spaces between the Carriages 
being closed up with canvas. 

tons. cwts. qrs. 
Weight of Carriage and Load .... 40 
Ten Passengers 15 



Gross weight .... 40 1 5 
From initial velocity 25*57 miles per hour, down Madeley Plane. 



Dist. 


(A 

1 


Times. 


Diffs. 


Speed. 


Dist. 


1/5 


Times. 


DiflTs. 


Speed, 


Yards. 


m 


h m s 
12 17 44-25 








Yards. 


44 


h m s 
12 19 57 


7-25 








60 


53-5 


9-25 








43 


20 4-5 


7-5 








59 


18 2 


8-5 






1500 


42 


12 


7-5 








58 


10 


8 








41 


20 


8- 


30-25 


27-05 





57 


17-75 


7-75 


33-5 


24-42 




40 


27-75 


7-75 








56 


25-25 


7-5 








39 


35-25 


7-5 








55 


33 


7-75 








38 


43-25 


8 








54 


40-5 


7-5 






2000 


37 


51-25 


8 


31-25 


26-18 




53 


48-75 


8-25 


31 


26-39 




36 


58-5 


7-25 






500 


52 


56 


7-25 








35 


21 6 


7-5 








51 


19 3-5 


7-5 








34 


14 


8 








50 


11-25 


7-75 








33 


21-75 


7-75 


30-5 


26-82 




49 


19 


7-75 


30-25 


27-05 


2500 


32 


30 


8-25 








48 


26-5 


7-5 








31 


37-5 


7-5 






1000 


47 


34-25 


7-75 








30 


45-25 


7-75 








46 


41-25 


7 








29 


53-25 


8 


31-5 


25-97 




45 


49-75 


8-5 


30-75 


26-61 




28 


22 1 


7-75 







ON RAILWAY CONSTANTS. 
Table (continued). 



217 



Dist. 


u5 


Times. 


DifFs. 


Speed. 


Dist. 


Vi 


Times. 


Diffs. 


Speed. 


Yards. 




h m s 








Yards. 




h m s 








3000 


27 


12 22 8-5 


7-5 






8500 


28 


12 29 53.25 


9-75 








26 


16-5 


8 








29 


30 2-5 


9-25 








25 


24-5 


8 ; 


n-25 


26-18 




30 


. 12-5 


10 




















31 


22-5 


10 39 1 


20-98 




24 


32-75 


8-25 




















23 


40-5 


7-75 








32 


33 


10-5 






3500 


22 


49 


8-5 






9000 


33 


42-5 


9-5 








21 


57 


8 . 


J2-5 


25-17 




34 


53-25 


10-75 








20 
19 


9^ 'i 


« 








35 


31 3-25 


10 


40-75 


20-07 




^0 (J 

13 




8 








36 


14 


10-75 








18 


21-25 


8-25 








37 


24-5 


10-5 






4000 


17 
16 


29-5 
38 


8-25 
8-5 


32-5 


25-17 


9500 


38 
39 


35-25 
46-25 


10-75 
11 


43 


19-02 




15 


46 


8 








40 


57 


10-75 








14 


54 


8 








41 


32 7-75 


10-75 








13 


24 1-75 


7-75 


32-25 


25-37 




42 


18-5 


10-75 






4500 


12 


10 


8-25 






10,000 


43 


29-5 


11 


43-25 


18-91 




11 


18 


8 








44 


40-25 


10-75 








10 


26 


8 








45 


51-75 


11-5 








9 


34 


8 


32-25 


25-37 




46 


33 2-5 


10-75 








8 


42-25 


8-25 








47 


13-75 


11-25 


44-25 


18-49 


5000 


7 


50-25 


8 






10,500 


48 


25 


11-25 








6 


58 


7-75 








49 


36 


11 








5 


25 6 


8 


32 


25-57 




50 


48 


12 








4 


14 


8 








51 


59 


11 


45-25 


18-08 




3 


22 


8 








52 


34 10 


11 






5500 


2 


30 


8 






11,000 


53 


21-25 


11-25 








1 


38 


8 


32 


25-57 




54 


33 


11-75 











46-25 


8-25 








55 


44-5 


11-5 


45-5 


17-99 




1 


54-25 


8 








56 


55-75 


11-25 








2 


26 2 


7-75 








57 


35 7-75 


12 






6000 


3 


10 


8 


32 


25-57 


11,500 


58 


19-25 


11-5 








4 


18 


8 








59 


32 


12-75 


47-5 


17-22 




5 


26-5 


8-5 








60 


44 


12 








6 


35 


8-0 








61 


55-75 


11-75 








7 


43-5 


8-5 


33-5 


24-42 




62 


36 8 


12-25 






6500 


8 


52-25 


8-75 






12,000 


63 


21 


13 


49 


16-69 




9 


27 0-5 


8-25 








64 


34-25 


13-25 








10 


9 


8-5 








65 


47-75 


13-5 








11 


18 


9 


34-5 


23-71 




66 


37 2 


14-25 








12 


26-5 


8-5 








67 


15 


13 


54 


15-15 


7000 


13 


35-25 


8-75 






12,500 


68 


29 


14 








14 


44-25 


9 








69 


43-25 


14-25 








15 


53-25 


9 


35-25 


23-21 




70 


58 


14-75 








16 


28 1-5 


8-25 








71 


38 13 


15 


58 


14-10 




17 


10-5 


9 








72 


28-25 


15-25 






7500 


18 


19-25 


8-75 






13,000 


73 


43-25 


15 








19 


28-75 


9-5 


35-5 


23-05 




74 


59 


15-75 








20 


38 


9-25 








75 




16 


62 


13-19 




21 


47-25 


9-25 








76 


39 31 


16 




12-78 




22 


56-25 


9 








77 


47-5 


16-5 






800C 


23 


29 5-25 


9 


36-5 


22-41 


13,500 


78 


40 4 


16-3 




12-39 




24 


M-25 


9 






13,59fc 




22 


18 




11-36 




25 


24 


9-75 






13,785 




41 5 










26 


34 


10 






13,915 




54-5 










27 


43-5 


9-5 


38-25 


21-39 


13,967 


« 


42 53-25 










Breeze down the Plan 


e. 













218 



REPORT— 1841. 



On comparing the general results of this experiment with those of the same 
train in its ordinary state,we obtain the following comparative table of effects. 







o 

c 

•s § 

CO 

e2 


bo 

11 

S 2 

H 


T3 
Oi 

1 

'5 
l-i 


Uniform speed on 
1 in 177. 


o 

Is 


o 

o o 

«.S 

a) 
a> 

eg- 


a t^ 

'> "" 
o a 

s- 

o c 
« & 

.§-§ 

H 


? IN 
« c 

1' 


bo© 

cro 

1-2 

si 


Train with 1 
Canvas J 

Train without 1 
Canvas J 

Difference ... 


Tons. 

40-75 
40-75 


Yards. 

13,967 
14,331 


m s 
25 9 
25 39 


Miles 
per hr. 

25-57 
23-37 


Miles 
perhr. 

25-37 
26-18 


Miles 
per hr. 

18-08 
19-25 


Miles 
per hr. 

14-10 
14-35 


m s 

8 2 
7 53 


m s 
10 47 
9 32 


m s 
4 31 
4 57 




364 


30 


2-20 


0-81 


117 


0-25 


9 


1 15 


26 



These results prove that the open spaces between the coaches have no 
effect on the resistance. 

On comparing the preceding experiments with those made with a train of 
waggons having high sides and ends capable of being taken down and laid flat 
upon them, it will be seen that although a change of frontage produce no ob- 
servable effect on the resistance, a change in the entire volume or bulk of the 
train produces a very considerable effect on the resistance to the tractive power. 

If that part of the resistance due to the a,ir depend altogether, or chiefly, 
on the frontage of the train, it would follow that by increasing the extent of 
the train by additional coaches, that part of the resistance would receive 
either no augmentation, or would be inconsiderably increased. To reduce 
this to the test of experiment, it was accordingly determined to run trains of 
various magnitude down inclined planes till they should attain uniform velo- 
cities, and thereby discover the manner in which their resistance would be 
affected. 

Experiments of this kind having been already made with trains of four 
coaches, and reported in the former part of this paper, it was now resolved 
to extend them to trains of six and eight coaches. The following are the 
results of these experiments, which in their details were conducted in all re- 
spects in the same manner as before. 



Number 








Uniform 


of 


Weight. 


Wind. 


Gradient. 


velocity 


Coaches. 








attained. 




Tons. 




One in 


Miles per 
hour. 


4 


15-6 


F 


96 


31-2 


4 


18- 


F 


96 


33-72 


4 


18- 


F 


177 


21-25 


4 


20-5 


F 


177 


22-9 


4 


20-5 


F 


89 


38-25 


4 


20-2 


F 


265 


1913 


6 


27-5 


A 


89 


32-3 


6 


27-5 


F 


89 


375 


6 


27-5 


F 


96 


34-6 


6 


27-5 


A 


96 


27-8 


6 


34-5 


C 


89 


35-3 


8 


36-5 


F 


89 


>36-5 


8 


40-75 


F 


177 


2615 


8 


40-75 


S 


177 


<17-7 


8 


40-75 


cc 


89 


31-4 



ON RAILWAY CONSTANTS. 219 

In the third column F expresses a favourable wind, A an adverse wind, C 
nearly calm, CC a dead calm, and S a side wind. 

The last experiment with a train of eight coaches, weighing nearly forty 
tons, shows that, in a dead calm, the resistance of that train at $\\ miles an 
hour amounted to the eighty-ninth part of its weight ; whereas the common 
estimate of the resistance of such a train at that speed has been hitherto about 
the 250th part of its weight ! This fact alone, were it unconnected with any 
others, would sufficiently illustrate the enormous extent of error which has 
prevailed hitherto in such estimations in railway practice. The third expe- 
riment with eight carriages was made with a side wind, the effect of which is 
abundantly manifested by the speed expressed in the last column. While 
the same train, moving with a fair wind down the Madeley plane, had a re- 
sistance equal to the 177th of its weight, at 26 miles an hour, its resistance 
with a side wind was of greater amount at 17"7 miles an hour. The relative 
effects of a fair and adverse wind are likewise exhibited in the third and 
fourth experiments with six coaches, down the Whiston plane. The velocity, 
which gives a resistance equal to the 96th part of the load, was 34^ miles an 
hour with a fair wind, and only 27J with an adverse wind. 

It is evident, from these experiments, that the manner in which the atmo- 
sphere resists a railway train, whatever it be, depends on the number of 
coaches forming the train, and that the foremost coaches do not, by clearing 
a passage for those which succeed them, produce any diminution of the total 
resistance, which is worthy of attention in practical operations. 

The writer of this Report pointed out long since a probable source of re- 
sistance, which the results above stated entitle to some attention. 

The wheels of the several carriages produce vortices of air around them, 
and play in some measure the part of fanners or blowers. A considerable 
force must be absorbed by so great a number of these wheels moving at 
such a velocity. In a train of eight carriages we have thirty-two three-feet 
wheels playing these parts of blowers, and revolving from four to five times 
in a second. How much force must be expended in maintaining such a 
motion, it is needless to say. But, besides this, another circumstance was 
observed. In these experiments, as well as in general railway practice, it is 
found that an extensive current of air moves beside a train, the current di- 
minishing in velocity as the distance from the train increases. Immediately 
contiguous to the side of the coaches the air moves with little less velocity 
than the coaches themselves. Outside that is another current, moving at a 
less rate, and beyond that another at a further diminished rate. There is 
thus a succession of currents, one outside another, exending to a consider- 
able distance at each side of the train. All the resistance produced by the 
lateral friction of each of these currents upon each other must be brought 
to the account of the aggregate resistance to the moving power ; and it is 
evident that these resistances will depend on the length of the train and the 
bulk of the coaches which form it. 

The following are the details of other experiments made on various gra- 
dients, with a view of illustrating the same practical principles. 



220 



REPORT — 1841. 



Six Passengers 



July 11th, 1839. 
Eight Second Class Carriages. 

tons. 

. 4.0 





Weight of Carriages and Load 



cwts, qrs. 

9 



Gross weight . 40 9 
Started spontaneously from a state of rest — on a curve of one mile radius- 







in 


a cutting 


sheltered from the wind. 












Times. 


Diffs, 


Speed. 






Times. 


Diffs. 


Speed. 





55 


1 45 








1000 


45 


1 50 0-5 


16-25 


■ 


12-49 


100 


54 


46 26-5 


86-5 




2-36 


1100 


44 


17 


16-5 


200 


53 


47 7-25 


40-75 




5-02 


1200 


43 


32-25 


15-25 




13-41 


300 


52 


38-25 


31 




6-60 


1300 


42 


47-25 


15 




13-63 


400 


51 


48 4-25 


26 




7-86 


1400 


41 


51 1-25 


14 




14-61 


500 


50 


27-5 


23-25 




8-80 


1500 


40 


15 


13-75 




14-87 


600 


49 


48-75 


21-25 




9-62 


1600 


39 


28-25 


13-25 




15-44 


700 


48 


49 7-75 


19 




10-76 


1700 


38 


41-25 


13 




15-73 


800 


47 


26-5 


18-75 




10-91 


1800 


37 


54-75 


13-5 


. 


15-73* 


900 


46 


44-25 


17-75 




11-52 


1900 


36 


52 7-25 


12-5 



Breeze down the Plane. 
* Stopped by the Break. 

July 11th, 1839. 
Eight Second Class Carriages as before. 



Weight of Carriages and Load 
Six Passengers 



Gross weight 



tons. cwts. qrs. 

40 
9 



40 







Started spontaneously from a state of rest on a straight line — in a cutting 

sheltered from the wind. 



5 


04 


Times. 


Diffs. 


Speed. 


P 


o5 
0( 


Times. 


Diffs. 


Speed. 





33 


2 20 








400 


29 


2 24 24 




39 


5-24 


10 


-9 


30-5 


30-5 






500 


28 


58 




34 


6-01 


20 


•8 


43-5 


13 






600 


27 


25 30 




32 


6-39 


30 


•7 


53-75 


10-25 






700 


26 


26 




30 


6-81 


40 


-6 


21 3 


9-25 






800 


25 


28-25 




28-25 


7-24 


50 


-5 


11-25 


8-25 






900 


24 


55 




26-75 


7-64 


60 


•4 


18-25 


7 






1000 


23 


27 20 




25 


8-18 


70 


•3 


26-5 


8-25 






1100 


22 


44-25 




24-25 


8-43 


80 


-2 










1200 


21 


28 7 




22-75 


8-99 


90 


-1 


42 


15-5 






1300 


20 


29 




22 


9-29 


100 


32 


49-5 


7-5 


109-5 


1-86 


1400 


19 


52 




23 


8-89* 


200 


31 


22 55 




65-5 


3-12 


1500 


18 


29 18-25 




26-25 




300 


30 


23 45 




50 


4-09 















Breeze down the Plane. 
* Stopped by the Break. 



ON RAILWAY CONSTANTS. 



221 



July 11th, 1839. 
Eight Second Class Carriages as before. 

tons. cwts. qrs. 
Weight of Carriages and Load . .40 
Six Passengers 9 



Gross weight 40 9 

Started spontaneously from a state of rest on a curve of one mile radius 
on embankment. 



Dist. 



Yds. 



100 

200 

300 

400 

500 

600 

700 

800 

900 

1000 

1100 



Posts. 



15 

14 

13 

12 

11 

10 

9 

8 

7 

6 

5 

4 



Times. 



m s 
38 30 

40 34 

41 40 

42 42 

43 37 

44 30-5 

45 23 

46 7 
44 

47 20 
55 

48 28 



Diffs. 


Speed. 


12-4 




1-65 


66 




3-10 


62 




3-30 


55 




3-72 


53-5 




3-82 


52-5 




3-90 


44 




4-65 


37 




5-53 


36 




5-68 


35 




5-84* 


33 




6-20 



Dist. 



Yds. 
1200 
1300 
1400 
1500 
1600 
1700 
1800 
1900 
2000 
2100 
2183 



Posts. 



3 
2 
1 

1 
2 
3 
4 
5 
6 



Times. 



m s 

48 59-5 

49 31 

50 3 
34 

51 6 
41 

52 21 

53 8 

54 8-5 

55 27 
57 54 



Diffs, 



31-5 

31-5 

32 

31 

32 

35 

40 

47 

60-5 

78-5 



Speed. 



6-49 
6-49 
6-39 
6-60 
6-39 
5-84 
511 
4-35 
3-38 
2-60t 



Train brought to rest on the Plane 1 in 267 without the Break. 

Breeze down the Plane. 

* End of curve. -f- Stopped. 



July 11th, 1839. 
Single Carriage, No. 12, descending on straight line. Gradient 1 in 267. 

tons. cwts. qrs. 
Weight of Carriage and Load ... 5 
Three Passengers 4 2 



Gross weight 5 4 2 
From initial velocity 12*21 miles per hour. 



Dist. 


Posts. 


Times. 


Diffs. 


Speed. 


Dist . 
Yds. 


Posts. 


Times. 


Diffs. 


Speed. 


Yds. 




h m s 










h m s 











29 


3 31 30-5 








1100 


40 


3 36 35-5 


52-5 




390 


100 


30 


47-25 


16-75 




12-21 


1200 


41 


37 25 


49-5 




4-13 


200 


31 


32 5 


17-75 




11-52 


1300 


42 


38 24-5 


59-5 




3-43 


300 


32 


23-25 


18-25 




11-21 


1400 


43 


39 30 


65-5 




3-12 


400 


33 


43 


19-75 




10-35 


1500 


44 


40 49 


79 




2-58 


500 


34 


33 4 


21 




9-74 


1600 


45 


42 6 


77 




2-66 


600 


35 


27 


23 




8-89 


1700 


46 


43 45-5 


99-5 






700 


36 


52 


25 




8-18 


1800 


47 


45 29 


103-5 






800 


37 


34 20 


28 




30 


1900 


48 


50 29 


300 






900 
1000 


38 
39 


56 
35 43 


36 
47 




7-68 
5-35 


1974 




54 50 






• 





Breeze down the Plane. 
• Stopped. 



222 



REPORT — 1841. 



July 11th, 1839. 
Single Carriage, No. 9, descending on straight line. Gradient 1 in 267- 

tons, cwts, qrs. 

Weight of Carriage and Load ... 5 
Three Passengers 0*42 



Gross weight 5 4 
From initial velocity 14"10 miles per hour. 





1/5 












tA 










Dist. 


ifi 


Times. 


Diffs. 


Speed. 


Dist. 


I 


Times. 


Diffs. 


Speed. 


Yards. 




h m s 








Yards. 




h m s 










28 


3 29 11 








1800 


46 


3 34 29 


22 




9-29 


100 


29 


27 


16 






1900 


47 


52 


23 






200 


30 


40 


13 


14-5 


14-10 


2000 


48 


35 14 


22 


22-5 


9-09 


300 


31 


56 


16 






2100 


49 


36 


22 




9-29 


400 


32 


30 12 


16 






2200 


50 


58 


22 






500 


33 


27 


15 




13-05 


2300 


51 


36 22 


24 


23 


8-89 


600 


34 


43 


16 




12-78 


2400 


52 


45 


23 






700 


35 


31 


17 






2500 


53 


37 11 


26 


24-5 


8-35 


800 


36 


17 


17 






2600 


54 


37 


26 




7-86 


900 


37 


33 


16 






2700 


55 


38 7 


30 






1000 


38 


51 


18 


17 


12-03 


2800 


56 


35 


28 


29 


7-05 


1100 


39 


32 8 


17 






2900 


57 


39 5 


30 




6-82 


1200 


40 


28 


20 






3000 


58 


38 


33 




6-20 


1300 


41 


45 


17 






3100 


59 


40 16 


38 




5-38 


1400 


42 


33 5 


20 


18-5 


11-05 


3200 


60 


59 


43 




4-75 


1500 


43 


25 


20 




10-22 


3300 


61 


42 15 


76 




2-69 


1600 


44 


47 


22 






3393 




44 25* 








1700 


45 


34 7 


20 


21 


9-74 















Breeze down the Plane. 
* Stopped. 

July 11 th, 1839. 
Four Second-Class Carriages, Nos. 5, 9, 29, 30. 

tons. cwts. qrs. 
Weight of Carriage and Load 20 
Three Passengers .... 042 



Gross weight 20 4 2 
From initial velocity 40*90 miles per hour, down Madeley Plane. 



Dist. 


05 

(2 


Times. 


Diffs. 


Speed. 


Dist. 


CA 


Times. 


Diffs. 


Speed. 


Yards. 




h m s 








Yards. 




h m s 










61 


6 50 58 










49 


6 52 3-25 


5-25 


21-75 


37-61 





60 
59 

58 
57 


51 4 
9 
14 
19-5 


6 
5 
5 
5-5 


21-5 


38-04 


1000 


48 
47 
46 
45 


9 

14-25 
20-25 
26 


5-75 
5-25 
6 
5-75 


22-75 


35-96 




56 
55 
54 
53 


25 
30-5 
35-75 
41-5 


5-5 
5-5 
5-25 
5-75 


22 


37-18 


1500 


44 
43 
42 
41 


32-25 
38 
44 
50-5 


6-25 
5-75 
6 
6-5 


24-5 


33-39 


500 


52 
51 
50 


47 
53 

58 


5-5 

6 

5 








40 
39 

38 


56 
53 2-25 
8-25 


5-5 

6-25 

6 







I 



ON RAILWAY CONSTANTS. 



223 



Table (continued). 



Dist. 


1 


Times. 


Diffs. 


Speed. 


Dist. 




Times, 


Diffs. 


Speed. 


Yards 




] m s 








Yards. 




h m s 








2000 


37 


6 53 15 


6-75 


24-5 


33-39 




15 


6 59 54-25 


9-25 


37-25 


21-96 




36 


21-25 


6-25 








16 


7 3 


8-75 








35 


27-75 


6-5 








17 


12-75 


9-75 








34 


34-25 


6-5 






7500 


18 


22-25 


9-5 








33 




6-5 


25-75 


31-77 




19 


32 


9-75 


37-75 


21-67 


2500 


32 


47-25 


6-5 








20 


41-5 


9-5 








31 


53-5 


6-25 








21 


51-25 


9-75 








30 


54 


6-5 








22 


1 0-5 


9-25 








29 


6-5 


6-5 


25-75 


31-77 


8000 


23 


10 


9-5 


38 


21-53 




28 


13 


6-5 








24 


20 


10 






3000 


27 


20 


7 








25 


30-25 


10-25 








26 


27 


7 








26 


40-25 


10 








25 


34-25 


7-25 


27-75 


29-48 




27 


50-25 


10 


40-25 


20-32 




24 


41-25 


7 






8500 


28 


2 


9-75 








23 


48-75 


7-5 








29 


10 


10 






3500 


22 


55-75 


7 








30 


20 


10 








21 


55 3 


7-25 


28-75 


28-45 




31 


30-25 


10-25 


40 


20-45 




20 


10 


7 








32 


40-25 


10 








19 


17 


7 






9000 


33 


50-25 


10 








18 


25 


8 








34 


3 0-5 


10-25 






4000 


17 


32-5 


7-5 


29-5 


27-73 




35 


10-5 


10 








16 


39-75 


7-25 








36 


21 


10-5 


50-75 


19-80 




15 


47-5 


7-75 








37 


31 


10 








14 


55 


7-5 






9500 


38 


41-25 


10-25 








13 


56 2 


7 


29-5 


27-73 




39 


52 


10-75 






4500 


12 


9-75 


7-75 








40 


4 2-5 


10-5 


41-5 


19-71 




11 


17-25 


7-5 








41 


13 


10-5 








10 


25 


7-75 








42 


23-75 


10-75 








9 


32-75 


7-75 


30-75 


26-61 


10,000 


43 


34-25 


10-5 








8 


40 


7-25 








44 


44-75 


10-5 


42-25 


19-36 


5000 


7 


48 


8 








45 


55-5 


10-75 








6 


55-75 


7-75 








46 


5 6 


10-5 








5 


57 3-25 


7-5 


30-5 


26-82 




47 


16-25 


10-25 








4 


11-25 


8 






10,500 


48 


27-5 


11-25 


42-75 


1913 




3 


19-25 


8 








49 


38 


10-5 






5500 


2 


27-25 


8 








50 


49 


11 








1 


35-25 


8 


32 


25-57 




51 


6 


11 











43-5 


8-25 








52 


10-25 


10-25 


42-75 


19-13 




1 


51-5 


8 






11,000 


53 


21 


10-75 








2 


58 


8-5 








54 


32-5 


11-5 






6000 


3 


7-75 


7-75 


32-5 


25-17 




55 


43 


10-5 








4 


16 


8-25 








56 


54 


11 


43-75 


18-70 




5 


24-5 


8-5 








57 


7 4-5 


10-5 








6 


33-25 


8-75 






11,500 


58 


15-5 


11 








7 


42 


8-75 


34-25 


23-89 




59 


27 


11-5 






6500 


8 


50-75 


8-75 








60 


38-5 


11-5 


44-5 


18-38 




9 


59 


9-26 








61 


50 


11-5 








10 


8-5 


8-5 








62 


8 1-25 


11-25 








11 


17 


8-5 


35 


2337 


12,000 


63 


13 


11-75 








12 


26-5 


9-5 








64 


25 


12 


46-5 


17-58 


7000 


13 


37-55 


9-25 








65 


37 


12 








14 


45 


9-25 








66 


47-75 


11-75 







224 



REPORT — 1841. 



Table (^continued). 



Dist. 


i 
I 


Times. 


Diffs, 


Speed. 


Dist. 


4 


Times. 


Diffs. 


Speed. 


Yards. 


67 


h m s 
7 9 1 


12-25 






Yards. 


75 


h m s 


13-25 






12,500 


68 


13-25 


12-25 


48-25 


16-95 




76 


7 10 57-25 


13-5 


53-25 


15-36 




69 


25-75 


12-5 








77 


11 11 


13-75 








70 


38-5 


12-75 






13,500 


78 


24-5 


13-5 








71 


51-75 


13-25 






13,785 


■ ■■ 


12 8 




, 






72 


10 4 


12-25 


50-75 


16-12 


13,915 


• •• 


32-25 








13,000 


73 
74 


17 
30-5 


13 
13-5 






14,242 

14,498 


... 


13 59-5 

14 45-5 * 









A Stiff Breeze down the Plane. 
* Stopped. 



July 11th, 1839. 
Four Second Class Carriages, Nos. 12, 20, 35, 22. 

tons. cwts. qrs. 

Weight of Carriage and Load 20 

Seven Passengers 102 



20 10 2 
From initial velocity 32*73 miles per hour, down Madeley Plane. 



Dist. 


Posts. 


Times. 


Diffs. 


Speed. 


Dist. 


Posts. 


Times. 


Diffs. 


Speed. 


Yards. 


61 


h m s 
7 11 4 








Yards. 


34 


[i m s 
7 14 3 


7 








60 


11 


7 








33 


10 


7 


29 


28-21 




59 

58 


16 
23 


5 

7 






2500 


32 


18 


8 









57 


29 


6 


25 


32-73 




31 
30 


26 
33 


8 

7 








56 


35 


6 








29 


40 


7 


30 


27-27 




55 


41 


6 




















54 


48 


7 








28 


48 


8 








53 


54 


6 


25 


32-73 


3000 


27 

26 


56 
15 4 


8 
8 






500 


52 
51 


12 1 

8 


7 
7 








25 


11 


7 


31 


26-39 




50 


14 


6 








24 


20 


y 








49 


21 


7 


27 


30-30 


3500 


23 
22 


28 
36 


8 
8 








48 


26 


5 








21 


44 


8 


33 


24-79 


1000 


47 


33 


7 




















46 


40 


7 








20 


52 


8 








45 


47 


7 


26 


31-46 




19 

18 


16 

8 


8 
8 








44 


53 


6 






4000 


17 


... 


9 


33 


24-79 




43 


13 


7 


















1500 


42 


7 


7 








16 


26 


9 








41 


14 


7 


27 


30-30 




15 
14 


35 
44 


9 
9 








40 


21 


7 








13 


53 


9 


36 


22-72 




39 


28 


7 




















38 


34 


6 






4500 


12 


17 2 


9 






2000 


37 


41 


7 


27 


30-30 




11 

10 
9 


11 
18 


9 

7 

10 








36 


48 


7 








28 


35 


23-37 




35 


56 


8 



















ON RAILWAY CONSTANTS. 



22" 



Table {continued). 



Dist. 


Posts. 


Times. 


Diffs. 


Speed. 


Dist. 


Posts. 


Times. 


DiflTs. 


Speed. 


Yards. 




h m s 








Yards. 




h m s 










8 


7 17 36 


8 








31 


7 24 37 


13 


52 


15-73 


5000 


7 
5 


45 

54 

18 3 


9 
9 
9 


35 


23-37 


9000 


32 
33 
34 


50 

25 3 

16 


13 
13 
13 








4 


13 


10 








35 


29 


13 








3 


22 


9 








36 


43 


14 


66 


12-39 


5500 


2 

1 


31 
40 


9 
9 


37 


2211 


9500 


37 

38 


57 
26 11 


14 
14 











49 


9 








39 


25 


14 








1 


58 


9 








40 


40 


15 


57 


14-35 


6000 


2 
3 


19 7 
17 


9 
10 


37 


22-11 




41 
42 


55 
27 10 


15 
15 








4 


27 


10 






10,000 


43 


25 


15 








5 


37 


10 








44 


40 


15 


60 


16-63 




6 

7 


47 
57 


10 
10 


40 


20-44 




45 
46 


55 
28 10 


15 
15 






G500 


8 


20 7 


10 








47 


27 


17 








9 


17 


10 






10,500 


48 


44 


17 


64 


12-79 




10 
11 


27 

38 


10 
11 


41 


19-95 




49 

50 


29 1 

18 


17 

17 








12 


50 


12 








51 


36 


18 


•^ 




7000 


13 


21 1 


11 








52 


53 


17 


69 


11-85 




14 
15 


12 
23 


11 
11 


45 


18-18 


11,000 


53 

54 


30 10 

28 


17 

18 








16 


34 


11 








55 


48 


20 








17 


44 


10 








56 


31 8 


20 


75 


10-91 


7500 


18 
19 


56 
22 8 


12 
12 


45 


18-18 


11,500 


57 
58 


28 
50 


20 
22 




9-29 




20 


20 


12 








59 


32 13 


23 








21 


32 


12 








60 


36 


23 




8-89 


8000 


22 

23 

24 


44 
56 

23 8 


12 
12 

12 


48 


17-04 




61 
62 


33 2 
27 


26 
25 


25-5 


8-02 




25 


21 


13 






12,000 


63 


55 


28 




7-30 




26 


33 


12 








64 


34 28 


33 




6-20 




27 


45 


12 


49 


16-69 




65 
66 


35 2 

38 


34 
36 




6-01 
5-68 


8500 


28 


58 


13 








Q7 


36 23 


45 




4-54 




29 


24 11 


13 






12,500 


68 


37 30 


67 




3-05 




30 


24 


13 






12,555 




39 8 






* 



A Stiff Breeze down the Plane. 



* Stopped at C8 post -\- 55 yards. 



184-1. 



226 



REPORT — 1841. 



July 12th, 1839. 



Six Second Class Carriages, Nos. 3.5, 9, 29, 22, 12, 20. 



Weight of Carriages and Load . 

Six Passengers 9 



tons. cwts. qrs. 
30 




Gross weight ... 30 9 
From initial velocity 25"57 miles per hour, down Madeley Plane. 



, 


n 






13 




in 






t: 


C/1 




Times. 


DifFs. 


<u 


U3 


U3 


Times. 


DifFs. 




Q 


(5 






eg- 


Q 


O 

0-1 






W 


Yds. 


61 


h m s 
1 36 53-5 








Yds. 


19 


h m s 

1 43 19-5 


11-5 








60 


37 2 


8-5 








18 


32 


12-5 








59 


10 


8 






4000 


17 


44-5 


12-5 


48 


17-04 





58 
57 


18-5 
26 


8-5 
7-5 


32-5 


25-17 




16 
15 


56 
44 8-5 


11-5 
12-5 








56 


34 


8 








14 


21 


12-5 








55 


42 


8 








13 


33-5 


12-5 


49 


16-69 




54 
53 


50 
58 


8 
8 


32 


25-57 


4500 


12 
11 


46-25 

58-75 


12-75 
12-5 






500 


52 


38 6 


8 








10 


45 11-75 


13 








51 




8-5 








9 


25 


13-25 


51-5 


15-88 




50 
49 


23 " 


8-5 
8 


33 


24-79 


5000 


8 

7 


38 
52-5 


13 
14-5 








48 


39 


8 








6 


46 6 


13-5 






1000 


47 


48-25 


9-25 








5 


20-75 


14-75 


55-75 


14-67 




46 
45 


56-5 
39 5-25 


8-25 
8-75 


34-25 


23-89 




4 
3 


36 
50-75 


15-25 
14-75 








44 


' 14 


8-75 






5500 


2 


47 4-75 


14 








43 


23 


9 








1 


19-5 


1475 


58-75 


13-92 


1500 


42 
41 


31-5 
40-25 


8-5 
8-75 


35 


23-37 





1 


34 
48-5 


14-5 
14-5 








40 


48-5 


8-25 








2 


48 3 


14-5 








39 


58-5 


10 






6000 


3 


19-25 


16-25 


59-75 


13-69 


2000 


38 
37 


40 7-75 
16-5 


9-25 

8-75 


36-25 


22-57 




4 
5 


35 

52 


15-75 
17 








36 


25-75 


9-25 








6 


49 9 


17 








35 


35 


9-25 








7 


27-5 


18-5 


68-25 


11-98 




34 
33 


44-25 
53-5 


9-25 
9-25 


37 


2211 


6500 


8 
9 


48 
50 9 


20-5 
21 






2500 


32 


41 2-5 


9 








10 


30-5 


21-5 








31 


11-25 


8-75 








11 


53 


22-5 


85-5 


9-56 




30 

29 


21 
30-5 


9-75 
9-5 


37 


2211 


7000 


12 
13 


51 14-75 
39 


21-75 
24-25 








28 


40-25 


9-75 








14 


52 2-5 


23-5 






3000 


27 


50-25 


10 








15 


27-25 


24-75 


94-25 


8-64 




26 
25 


42 0-5 
11-25 


10-25 
10-75 


40-75 


20-07 




16 
17 


53-5 
53 22-5 


26-25 
29 




7-79 
7-05 




24 


22-25 


11 






7500 


18 


56-5 


34 




601 




23 


33-5 


11-25 








19 


54 37-25 


40-75 




502* 


3500 


22 


45 


11-5 








20 


55 25-5 


48-25 








21 


56-5 


11-5 


45-25 


18-08 


7800 


21 


56 31-25 


65-75 








20 


43 8 


11-5 






7881 




58 33-5 









* Stopped at 21 post + 81 yards. 

Breeze from the west, or nearly at right angles to road. 



ON RAILWAY CONSTANTS. 

July 12th, 1839. 

Eight Second Class Carriages. 

tons. cwts. qrs. 
Weight of Carriages and Load . . 40 
Six Passengers 9 



227 



Gross weight ... 40 9 
From initial velocity 20"07 miles per hour, down Madeley Plane. 





m 






TJ 


, 


«? 






'6 


Ul 


tn 


Times. 


Diffs. 


01 




Q 


Times. 


Diffs. 


01 


Q 


(S 






^ 


s 


(S 






CO 


Yds. 


61 


h m s 
2 30 58 








Yds, 


18 


h m s 
2 38 16-25 


11 








60 


31 14 


16 




12-78 


4000 


17 


27-25 


11 


43 


19-02 





59 

58 
57 


27 
38 
48-75 


13 
11 
10-75 




15-73 
18-59 
19-02 




16 
15 
14 


38 

49-75 
39 


10-75 
11-75 
10-25 








56 


59 


10-25 








13 


11 


11 


43-75 


18-70 




55 
54 
53 


32 9 
19-25 
29-5 


10 

10-25 

10-25 


40-75 


20-07 


4500 


12 
11 

10 


22 
33 

44-25 


11 
11 
11-25 






500 


52 


40 


10-5 








9 


55-0 


10-75 


44 


18-59 




51 
50 
49 


50 

33 

9 


10 

10 

9 


39-5 


20-71 


5000 


8 
7 
6 


40 6 
17-5 
29-25 


11 

11-5 

11-75 








48 


19 


10 








5 


■ 41 


11-75 


46 


17-78 


1000 


47 
46 
45 


29-25 

39 

49-25 


10-25 

9-75 

10-25 


40-25 


20-33 


5500 


4 
3 
2 


52-75 
41 4 


11-75 
11-25 
11-5 








44 


58-5 


9-25 








1 


" 27-25 


11-75 


46-25 


17-69 


1500 


43 
42 
41 


34 8-5 
18 
27-75 


10 

9-5 
9-75 


38-5 


21-25 





1 
2 


39 
50-5 
42 1-5 


11-75 

11-5 

11 








40 


37-5 


9-75 






6000 


3 


13-25 


11-75 


46 


17-78 


2000 


39 
38 
37 


47-25 
56-25 
35 5-5 


9-75 

9 

9-25 


37-75 


21-67 




4 

5 
6 


25-75 
37-75 
50-25 


12-5 

12 

12-5 








36 


15-5 


10 








7 


43 3-25 


13 


50 


16-36 




35 
34 
33 


25 
35 
44-75 


9-5 
10 
9-75 


39-25 


20-84 


6500 


8 

9 

10 


16-25 

29-5 

43-5 


13 

13-25 

14 






2500 


32 


54-25 


9-5 








11 


57 


13-5 


53-75 


15-22 




31 

30 

29 


36 3-5 
13-25 
23 


9-25 
9-75 
9-75 


38-25 


21-39 


7000 


12 
13 
14 


44 10-25 
24-5 
39 


13-25 
14-25 
14-5 








28 


32-75 


9-75 








15 


53-25 


14-25 


56-25 


14-54 


3000 


27 
26 
25 


42-75 
53 
37 2-5 


10 

10-25 
9-5 


39-5 


20-71 


7500 


16 
17 

18 


45 7 
22 

37 


13-75 

15 

15 








24 


12-5 


10 








19 


53 


16 


59-75 


13-69 


3500 


23 
22 
21 


22-5 
33-5 
44-25 


10 
11 
10-75 


41-75 


19-59 




20 
21 
22 


46 8 
23-75 
39-75 


15 

15-75 

16 








20 


54-5 


10-25 






8000 


23 


56 


16-25 


63 


12-98 




19 


38 5-25 


10-75 



















q2 



228 



REPORT — 1841. 



Table (co7itinued). 











































Dist. 


o 
Oh 


Times. 


Diffs. 


Speed. ! 


Dist. 


o 


Times. 


Diffs. 


Speed. 


Yards. 




h m s 








Yards. 




h m s 










24 


2 47 13 


17 








40 


2 52 50-75 


26-75 








25 


30-5 


17-5 








41 


53 15-5 


24-75 








26 


48-5 


18 








42 


43 


27-5 








27 


48 6 


17-5 


70 


11-69 


10,000 


43 


54 7-75 


24-75 


103-75 




8500 


28 


24 25 


18-25 








44 


35 


27-25 








29 


43 25 


19 








45 


55 3 


28 








30 


49 2-5 


19-25 








46 


32-5 


29-5 








31 


22-25 


19-75 


76-25 


10-73 




47 


56 3 


30-5 






9000 


32 
33 
34 
35 


42-5 
50 3-5 

26 
48-5 


20-25 
21 
22-5 
22-5 


86-25 


9-48 


10,500 


48 
49 
50 
51 
52 


35-75 

57 8 
42-5 

58 21 

59 2 


32-75 

32-25 

34-5 

38-5 

41 








36 


51 11 


22-5 






11,000 


53 


53 


51 








37 


34-75 


23-75 






11,100 


54 


3 1 15 


82 






9500 


38 
39 


58-5 
52 24 


23-75 
25-5 


95-5 




11,154 




2 42-5 


* 







Wind from west, but rather less than in preceding. 

* Stopped at 42 +37 yards ; the last 600 or 800 yards were in a cutting completely shel- 
tered from the wind. 



July 12th, 1839. 

Experiments continued on Sutton Inclined Sutton Plane. 

Four Second Class Carriages, Nos. 30, 5, 20, 12. 



Weight of Carriages and Load 
Six Passengers 



tons. cwts. qrs. 

20 

9 



Gross weight 



.... 20 9 
From initial velocity 33"64; miles per hour, down Sutton Incline. 



. 


«3 






TJ 




« 






13 


(A 


Ui 


Times. 


Diffs. 


a> 


U3 


(fi 


Times. 


Diffs. 


a 


Q 


Cl( 






CO 


« 


^ 






a. 
w 


Yds. 




h m s 








Yds. 




h m s 










4 


6 20 53-5 








1210 


11 


6 22 30 


6-25 








3 




6 






1320 


12 


36 


6 


24-75 


36-36 





2 
1 




21 6 
12-5 
19-25 


6-5 
6-5 
6-75 


25-75 


34-95 


1430 
1540 
1650 


13 
14 
15 


42-25 

48-25 
54-75 


6-25 

6 

6-5 






110 


1 


26-25 


7 






1760 


16 


23 0-5 


5-75 


24-5 


36-73 


220 
330 
440 


2 
3 

4 


32-75 
39-25 
46 


6-5 
6-5 
6-75 


26-75 


33-64 


1870 
1980 
2090 


17 

18 
19 


6 
12-25 

18 


5-5 

6-25 

5-75 






550 


5 


52-5 


6-5 






2200 


20 


24 


6 


23-5 


38-29 


660 
770 

880 


6 

7 
8 


58-5 
22 5 
11-25 


6 

6-5 

6-25 


25-25 


35-64 


2310 
2420 


21 
22 


30-25 
36 


6-25 
5-75 


6 


37-50 


990 


9 


17-25 


6 






2530 


23 


42-5 


6-5 






1100 


10 


23-75 


6-5 






2640 


24 


49 


6-i) 







ON BAILWAY CONSTANTS. 



229 







. 




Table 


conti' 


nued 


)• 








(/J 

5 


t/1 


Times. 


Diffs. 


1 




(2 


Times. 


Diffs. 


13 


Yds. 
2750 

2860 
2970 

3080 
3190 
3300 

3410 
3520 

3630 
3740 

3850 
3960 

4070 


25 

26 
27 

28 
39 
30 

31 
32 

33 
34 

35 
36 

37 


h m s 
6 

24 2.5 
9 

16-75 

24-5 

32-25 

40 

48-25 

57 

25 5-75 

15 
24-25 

34-5 


6-5 

7 
6-5 

7-75 
7-75 
7-75 

7-75 

8-25 

8-75 
8-75 

9-25 
9-25 

10-25 


6-5 
6-75 

7-75 
8 

8-75 
9-25 


34-61 
33-33 

29-03 

28-12 

25-71 

24-32 
21-95 


Yds. 

4180 

4290 
4400 

4510 
4620 
4730 
4840 
4950 
5060 
5170 

5203 

5643 
5869 


38 

39 
40 

41 
42 
43 
44 
45 
46 
47 
I 

XIII— 
IV 

I 

xni— 

II 


h m s 
6 25 4-5 

55-75 

26 6-25 

18-25 
31-25 
45 
59-5 

27 15-25 
33 
52 

58 

29 40 
32 


10-5 

10-75 
10-5 

12 

13 

13-75 

14-5 

15-75 

17-75 

19 

* 


10-62 


21-43 

21-17 

18-75 
17-30 
16-36 
15-51 
14-28 
12-67 
11-84 



A light breeze from west, or down the Plane. 
* Stopped at xm- mile post, -\- 226 yards. 



July 12th, 1839. 
Six Second Class Carriages, Nos. 30, 5, 20, 12, 22, 29. 



Weight of Carriages and Load 
Six Passengers 



tons, cwts, qrs. 
30 
9 



Gross weight . ' . 30 9 
From initial velocity 26"4'7 miles per hour, down Sutton Incline. 



Dist. 


1 


Times. 


Diffs. 


Speed. 


Dist. 


2 


Times. 


Diffs. 


Speed. 


Yards. 




h m s 








Yards. 




h m s 










4 


7 23 31 








2090 


19 


7 26 20-75 


6-75 








3 


38-5 


7-5 






2200 


20 


27-25 


6-5 


25-5 


35-29 





2 

1 



46-75 
55 
24 3-5 


8-25 
8-25 
8-5 


32-5 


27-69 


2310 
2420 


31 
23 


34 
40 


6-75 
6 


6-38 


35-29 


110 
220 
330 


1 
2 
3 


12-25 

20 

28-25 


8-75 
7.75 
8-25 






2530 
2640 
2750 


23 
24 
25 


47 
54 
27 0-5 


7 
7 
6-5 


6-83 


32-92 


440 


4 


36 


7-75 


32-5 


27-69 


2860 


26 


7-5 


7 




3214 


550 


5 


44 


8 






2970 


27 


15 


75 




30-00 


660 


6 


51-5 


7-5 






3080 


28 


23 


8 






770 


7 


59 


7-5 






3190 


29 


31 


8 






880 


8 


25 6 


7 


30 


30-00 


3300 


30 


39 


8 


8 


28-12 


990 


9 


13 


7 






3410 


31 


47 


8 




28-12 


1100 


10 


20-25 


7-25 






3520 


32 


55-5 


8-5 




26-47 


1210 
1320 


11 
12 


27-5 
34-5 


7-25 

7 


28-5 


31-58 


3630 
3740 


33 
34 


28 4-75 
14 


9-25 
9-25 






1430 


13 


41-25 


6-75 






3850 


35 


23-25 


9-25 


9-25 


24-32 


1540 
1650 
1760 


14 
15 
16 


48-25 
55 
26 1-75 

8 
14 


7 

6-75 

6-75 

6-25 
6 


27-25 


33-02 


3960 
4070 

4180 
4290 


36 
37 

38 
39 


33-5 
43-75 

54-5 
29 5-5 


10-25 
10-25 

10-75 
11 


10-25 


21-95 

20-93 
20-45 


1870 
1980 


17 

18 



230 



REPORT — 1841. 











Table (continued). 








^ 


u5 








TS 


. 


UJ 






V 


<A 


^ 


Times. 


Diffs. 


0) 


en 


f^ 


'Times. 


Diffs. 


<i} 


Q 


Ph 








^ 


s 


di 






a, 


Yds. 




h m s 








Yds. 




h m s 








4400 


40 


7 29 17-5 


12 




18-75 


4950 


45 


7 30 29-25 


17 




13-23 


4510 


41 


30 


12-5 




18-00 


5060 


46 


48 


18-75 




12-00 


4620 


42 


43-25 


13-25 




16-98 


5170 


47 


31 8 


20 




11-25* 


4730 


43 


57-25 


14 




1607 


5203 


I 


14 








4840 


44 


30 12-25 


15 




15-00 


5616 


^^« 


34 3 









Nearly calm. 
* Stopped at XIII — mile post +413 yards. 



July 12th, 1839. 
Eight Second Class Carriages. 



Weight of Carriages and Load 
Six Passengers 



tons. cwts. qrs. 

40 

9 



Gross weight . 40 9 
From state of rest, down Sutton Incline Plane. 



1^ 
5 


(5 


Yards. 










110 


1 


220 


2 


330 


3 


440 


4 


550 


5 


660 


6 


770 


7 


880 


8 


990 


9 


1100 


10 


1210 


11 


1320 


12 


1430 


13 


1540 


14 


1650 


15 


1760 


16 


1870 


17 


1980 


18 


2090 


19 


2200 


20 


2310 


21 


2420 


22 


2530 


23 


2640 


24 


2750 


25 


2860 


26 


2970 


27 



Times. 



m 
52 

53 



54 



55 



s 


55 
17 
35 
50 

3-5 
16 

27-25 
38 

48-25 
58-25 

7-75 
16-5 
25 

34 
41-75 

50 
57-75 

5 
12-75 

19-75 

27-5 

34-25 

41-75 
49-5 

57 
57 4-5 
13 



56 



Diffs. 



55 
22 
18 
15 
13-5 
12-5 
11-25 
10-75 
10-25 
10 
9-5 
8-75 
8-5 

9 

7-75 

8-25 
7-75 

7-25 
7-75 

7 

7-75 

6-75 

7-5 
7-75 

7-5 

7-5 
8-5 



8-37 



7-5 

7-17 

7-67 

7-83 



Speed, 



4-09 
10-22 
12-50 
15-00 
16-66 
18-00 
20-00 
20-93 
21-95 
22-50 
23-68 
25-71 
26-47 

26-86 

27-27 
29-03 

30-00 



31-39 
29-51 

28-72 



Yards 
3080 
3190 

3300 
3410 

3520 
3630 
3740 

3850 
3960 

4070 
4180 

4290 
4400 
4510 
4620 
4730 
4840 
4950 
5060 
5170 
5203 
5485 



28 
29 

30 
31 

32 
33 
34 

35 
36 

37 

38 

39 
40 
41 
42 
43 
44 
45 
46 
47 



xm— 

IV 



Times. 



h m s 

7 57 22 

30-5 

39-25 
49 

58 

58 8 
18 

29 
40 

51-75 

59 3-5 

16 
29 

43-25 
58 

8 14 

31-75 

51-5 

13 

38-5 

47 

19 



1 



Diffs. 



8-75 
9-75 

9 

10 
10 

11 
11 

11-75 
11-75 

12-5 

13 

14-25 

14-75 

16 

17-75 

19-75 

21-5 

25-5 



8-75 



9-25 



9-66 



11 



11-75 



Speed. 



25-71 



24-32 



23-27 



20-45 



19-15 

18-00 
17-30 
15-79 
15-25 
14-06 
12-67 
11-39 
10-46 
8-82* 



Dead calm. 
* Stopped at XIII j^mile post + 282 yards. 



ON RAILWAY CONSTANTS. 



231 






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Z 
H 

CO 



233 REPORT — 1841, 

The obvious tendency which this body of experiments had to support, a prin- 
ciple — which the author of this Report had advanced and supported before 
a Committee of the House of Lords in the year 1835, but which then and 
ever since was declared by engineers to be paradoxical and absurd, and one 
which had no foundation in practice — suggested the trial of one extended 
experiment, by which the truth or falsehood of that doctrine would be put 
beyond all doubt. The doctrine referred to vf&s, that a railway laid doivn 
with gradients not exceeding twenty feet a mile would be for all practical pur- 
poses, nearly if not altogether as good as a railway of equal length laid down 
from terminus to terminus on a dead level. The grounds on which he advanced 
this doctrine were, that a compensation would be obtained on the descending 
gradients for the disadvantages of the ascending gradients. This compensa- 
tion would be either in time, or power, or both, which would be saved in 
the descent ; and he consequently maintained, that a railway graduated 
within the limits proposed would be worked at as great an average speed, 
and with as small an expenditure of moving power, as a dead level*. 

If the principle now advanced be admitted, it will follow that the whole 
amount of inconvenience which would ensue from the adoption of eighteen 
or twenty-foot gradients would be a variation in the speed of transport. The 
average speed, the time of completing the journey, the expenditure of power, 
the expense of maintaining the line, and supplying it with locomotive power, 
would be the same. The great practical importance of these circumstances 
is quite evident. 

To reduce this question to the immediate test of experiment, it was deter- 
mined to prepare an engine and full train of twelve coaches loaded as such 
a train would be in the ordinary traffic of a railway, and to run this train on 
the railway from Liverpool to Birmingham and back, observing the moment 
of passing each quarter-mile post, and obtaining thereby the actual speed 
with Avhich each gradient, from one end to the other of the line, was ascended 
and descended, and the speed on the levels. By taking a mean of the speed 
in ascending and descending the gradients, it would be necessary, if the prin- 
ciple maintained by the writer of this Report were valid, that this mean 
should be exactly or very nearly equal to the speed on the level. 

The experiment was accordingly made on the 16th July 1839, and the fol- 
lowing are the details of it : — 

Experiment with the Hecla Locomotive Engine. 

On a trip from Liverpool to Birmingham and back, with a load consisting 
of the Tender and Twelve Second Class Grand Junction Carriages. 
Weather fine and calm ; rails dry ; water in the tender warm. 





tons. cwt. 


qrs. 


tons. 


cwt. 


qrs. 


Hecla Engine . 






12 








Tender .... 


10 











Carriages, No. 5, 


5 











Do. 30, 


5 
1 forward 





20 








Carrie( 


32 









1 



* The principle here advocated has nothing in common with that of tlie undulating rail- 
way proposed some years ago. That project had for its foundation a supposed advantage, 
derivable from the acceleration of the load descending inclined planes of greater inclination 
than the angle of repose; it was maintained, that the momentum thus acquired woidd com- 
pensate for the steepness of the plane in the ascent, and it was essential to this project that 
the gradients should exceed the angle of repose. It is, on the contrary, essential to the prin- 
ciple maintained in the present Report, that the gradients should not exceed the angle of 
repose. Tlie principle of what was called the undulating railway was evidently fallacious. 



ON RAILWAY CONSTANTS. 



233 



tons. cwt. qrs. tons. cwt. qrs. 

Brought forward 32 

Carriages, No. 29, 5 

Do. 9, 5 

Do. 12, 5 

Do. 20, 5 

Do. 22, 5 

Do. 35, 5 

Do. 31, 5 0, 

Do. 5, 5 

Do. 23, 5 

Do. (open) 7, 5 50 

Gross weight of Train ... 82 

Dimensions of the Hecla. 

ft. in. 

Diameter of Driving Wheels 5 Q 

Diameter of Cylinder 121 

Length of Stroke 18 

Diameter of Blast-pipe 2J 

Internal Dimensions of Firebox. 

Width crosswise 3 6i- 

Length lengthwise 2 4^ 

Depth from underside of roof to top of Grate Bars 3 4I 
Number of Tubes 117. 

Length of Tubes 8 65 

External diameter 1# 

Heating surface per lineal foot . . . -375 sq. feet. 
Heating surface of Firebox .... 45-38 do. 
Heating surface of Tubes 373'7 do. 



Total heatinsr surface 



419-08 



do. 



" Hecla," Tender and Twelve Carriages. 
From Liverpool to Birmingham. 



1 
1 

a 


1 


Times. 


i 

z 
3 


S to 


S 


B 




1 




1 
S 


Times. 


c 


an 


u 
Oi 

Mi 




Fall . 


12 
3 

2 
2 

3 
3 

1 
2 
3 

4 

I 


h m s 
10 28 12 

29 33 

30 25 

31 46 

32 23 
57 

33 28 
58 

34 26 
53 

35 20 


81 
52 
81 
37 
34 
31 
30 
28 
27 
27 




11-11 

17-30 
22-22 
24-32 
26-47 
29-03 
30-00 
32-14 
33-33 
33-33 




Fall 

to'dt 


2 
3 

5 
1 
2 
3 

6 
1 
2 

3 

7 


h m 8 
10 35 46 

36 12 
38 

37 3 
29 
55 

38 21 
47 

39 14 
39 

40 6 


26 
26 
26 
25 
26 
26 
26 
26 
27 
25 
27 


© 

© 

■to 


34-61 





234 



REPORT — 1841. 



Table (^continued). 



ft Times. 



Rise 



9fi 8 



Level 



Fall 



10 



13 



10 40 37 
41 13 



47 



a S 



Rise 



80 y 



Fall 



27 



Level. 3 
Rise r28 

-^ L 1 



12 



52 27 

56 

53 27 
58 

54 30 

55 35 
56 

45 

57 27 

58 11 
54 

59 38 

20 
55 

1 27 



ii o 



29-03 
2500 
21-43 
18-00 
15-56 
13-63 
18-37 
23-68 
26-47 
27-27 



30-00 



33-33 
32-14 
21-07 
20-00 
21-95 
24-32 
23-68 
20-93 
28-42 
3214 



Slacknd. 
do. ■S c 
do. -2 2 

do.^f-; 

do.-sS 

do. !=« 

do. tx^ 

B " 

a" 

Stopd. c 
start. S 

C 



14-75 
18-00 
21-68 
24-32 
27-27 
28-12 
30-51 
31-03 

31-58 
31-03 
29-03 
29-03 
28-12 
27-70 
27-27 
24-32 
21-43 
20-45 
20-93 
20-45 
21-43 
25-71 
28-12 
31-03 
31-03 
34-61 
33-33 
33-33 
30-00 



ft 
S 



Rise 

1 

3¥0 



Level ■ 



Rise 
1 

4*0 



Rise 

!__ 

1585 



Fall 
1 ■< 

?Fo 



29 



30 



31 



32 



Level ■ 



Rise 
1 

400 



Rise 

1 



r33 



2200 

Rise 

I 

Level 



Rise 

1 

4.40 



34 



35 



36 



37 



38 



39 



Times. 



12 



Level < 



40 



41 



42 



m s 

4 44 

5 13 

48 

6 22 
55 

7 27 
58 

8 28 
58 

9 28 

10 
32 

11 3 
41 

12 47 

16 20 
53 

17 53 

18 32 

19 6 
37 

20 7 
37 

21 10 
39 

22 12 
45 

23 19 
51 

24 24 
55 

25 26| 31 
55| 29 

26 25 
55 

27 27 

28 
33 

29 7 
40 

30 12 
43 

31 14 
43 

32 15 
47 

33 19 
52 

34 22 
52 

35 22 
52 

36 21 
50 

37 20 
50 

38 19 



29 
29 
35 
34 
33 
32 
31 
30 
30 
30 
32 
32 
31 
38 



60 
39 
34 
31 
30 
30 
33 
29 
33 
33 
34 
32 
33 
31 



30 
30 
32 
33 
33 
34 
33 
32 
31 
31 
29 
32 
32 
32 
33 
30 
30 
30 
30 
29 
29 
30 
30 
29 



S bo 

go 

0« 






CO 3 

CJ o 



49 30 



31-03 
31-03 
25-71 
26-47 
27-27 
28-12 
29-03 
30-00 
30-00 
30-00 
28-12 
28-12 
29-03 
23-68 



15-00 
23-07 
26-47 
2903 
30-00 
30-00 

29-03 



27-27 



29-03 
29-03 
31-03 
30-00 
30-00 
28-12 
27-27 
27-27 
26-47 
27-27 
28-12 
2903 
29-03 



Stop. ^ 
Start. 1 



29-50 

28-12 
28-12 
27-27 
3000 

3000 



30-71 



ON RAILWAY CONSTANTS. 



235 



Table (continued). 



g 

1 


1" 


Times. 


C 

£ 

f? 


(1> . 
O bo 
C 0) 


Cue 


1 

i 


'■3 
2 


i 


Times. 


u 

So 


tu • 

v bo 

Is 


u 

8g 

2-= 




o 


i 




5 


QS 


g 


a 


O 


1 




5 


p« 


S 


K 




h m s 












h m s 












' 2 


12 39 18 


29 










r 3 


1 21 20 


26 




34-61 






3 


47 


29 


CO 


30-71 






57 


46 


26 




34-61 






43 


40 16 


29 








1 


22 13 


27 


-1 






Level <j 


1 


45 


29 










9, 


40 


27 












42 








stop. % 


Fall 

1 ^ 


3 


23 7 


27 


■* 










47 30 








start. £ 


59 


58 


35 


28 


f *>» 


33-16 






3 


48 12 












1 


24 2 


27 


<N 








^44 


49 18 


66 




13-63 






2 


30 


28 










1 


50 8 


50 




18-00 






3 


56 


26 








Rise 


2 


54 


46 




19-56 






[59 


25 23 


27 


-l 






1 • 

350 


3 


51 35 


41 




21-95 






1 


49 


26 








45 


52 15 


40 




22-50 






2 


26 17 


2S 










1 


53 


38 




23-68 




Fall 


3 


43 


26 


s^ 


32-58 






- 2 


53 30 


37 




24-32 




1 ■{ 


60 


27 11 


28 


(«■■> 






3 


54 6 


36 


■ 






fiJO 


1 


38 


27 










46 


42 


36 










2 


28 8 


30 










1 


55 18 


36 










3 


37 


29 










2 


51 


33 










61 


29 5 


28 


-1 






Rise 


3 


56 31 


40 


oo 








r 1 


33 


28 








2W5 1 


47 


57 8 


37 


1— 1 


24-87 






2 


30 2 


29 










1 


46 


38 


CO 








3 


30 


28 










2 


58 22 


S^ 










62 


59 


29 






Sm. low. 




3 


58 


36 










1 


31 27 


28 






Bd.coke. 




48 


59 33 


35 










2 


55 


28 










1 


1 8 


35 










3 


32 23 


28 










-■ 2 

3 
49 


45 

1 21 

59 


37 
36 
38 


in 

CO 


24-66 

23-68 




Fall 


63 

1 
2 


51 
33 19 

47 


28 
28 

28 


© 

CO 


31-36 






1 


2 37 


38 




23-68 




505 


3 


34 16 


29 


•x 








2 


3 17 


40 


-^ 








64 


44 


28 








Rise 


3 


57 


40 










1 


35 14 


30 








1 I 
T77 "1 


50 


4 38 


41 










2 


43 


29 










1 


5 20 


42 










3 


36 13 


30 










2 


6 


40 


22-25 






65 


42 


29 










3 


40 


40 










1 


37 12 


30 










51 


7 20 


40 










2 


41 


29 










1 


8 1 


41 










3 


38 11 


30 










2 


41 


40 










[66 


40 


29 . 


' 


31-03 






- 3 


9 22 


41 




21-95 






1 


39 12 


32 




28-12 






52 


10 


38 




23-68 






2 


45 


33 




27-27 




Rise 


1 


37 


37 




24-32 




Fall 


3 


40 18 


33 




27-27 




TJo ' 


2 


11 14 


37 




24-32 




1 ■{ 


67 


53 


35 . 




25-71 




3 
53 


49 
12 24 


35 
35 




25-71 
25-71 




'2 105 


2 
3 


42 7 
42 


1-14 . 
35 . 




24-32 






25-71 




1 


58 


34 




26-47 






68 


43 21 


39 . 




23-07 




Level • 


r 2 
3 


13 32 

14 7 


34 
35 




26-47 
25-71 


Slackd. 






44 30 
51 5 








Stopped. 
Started. 




r64 


15 1 


54 




16-66 


do, aj 




2 


52 31 












1 


48 


47 




1915 


do. 1 


Rise 


3 


53 27 


56 . 




16-07 






2 


16 52 


64 




14-06 


do. 1 


63 C, 


69 


54 16 


49 




18-37 






3 


17 30 


38 




23-68 


^ 




1 


58 


42 . 




31-43 




Fall 

I -1 


55 


18 5 


35 




25-71 






2 


55 36 


38 . 




23-68 




1 


36 


31 




29-03 






r 3 


56 15 


39 . 




23-07 




?Uo 


2 


19 6 


30 




30-00 




Level i 


70 


50 


35 . 




25-71 






3 


33 


27 


-\ 








1 


57 23 


33 . 




27-27 






50 

1 




20 1 

27 
54 


28 
26 
27 


.»>. 
(N 


33-33 




Rise 

too 


^ 2 
3 
.71 


54 

58 27 

59 


31 . 
33 . 
33 . 




29-03 
27-27 






27-27 


1 





























236 



REPORT — 1841. 



Table (continued). 



o 



Rise 

-A- -i 
¥00 



Level • 



Rise 

1 

¥40 



Rise 

1 

530 



Level ■ 



1 
2 
3 

72 
1 
2 
3 

73-1 
2 
3 

74 
1 
2 
3 

75 
1 
2 
3 

76 
1 
2 
3 

77 
1 
2 
3 

78 
1 
2 
3 

79 
1 
2 
3 

80 
1 
2 
3 

81 
1 
2 
3 

82 
1 
2 
3 

83 



2 

3 

84 



Times. 



h. m. 

1 59 

2 

1 
2 

4 

5 

6 

7 
7 
8 



10 
11 

12 

13 

14 
15 

16 

17 
18 

19 
20 



34 

8 
41 
15 
50 
23 
57 

1 
30 


30 

2 
36 

7 
39 
12 
45 
20 
55 
30 

5 
38 
12 
47 
22 
57 
31 

8 
43 
21 
57 
34 
11 
47 
23 





21 10 
45 

22 20 
53 

23 27 

24 3 
38 

25 14 
49 

26 25 

27 30 

31 42 

32 59 

33 46 

34 25 






34 
34 
33 
34 
35 
33 
34 
64 
29 
30 
30 
32 
34 
31 
32 
33 
33 
35 
35 
35 
35 
33 
34 
35 
35 
35 
34 
37 
35 
38 
36 
37 
37 
36 
36 
37 



35 
35 
33 
34 
36 
35 
36 
35 
36 



47 
39 



go 



26-47 



26-87 

28-12 
31-03 
30-00 
30-00 
28-12 

27-70 

28-12 
27-27 
27-27 
25-71 
25-71 






25-45 



19-15 
23-07 



Fall 

joO 



85 



86 



87 



88 



89 



90 



Fall ' 
1 1 



Stop. £ 

start. S 



Level ■ 



Rise 

1 < 
3F7" 



91 



92 



93 



94 



95 



96 



Times. 


O 

O 

G 

1 
5 


h. m. s. 
2 34 58 


33 


35 28 


30 


57 


29 


36 25 


28 


52 


27 


37 17 


25 


44 


27 


38 8 


24 


32 


24 


57 


25 


39 22 


25 


47 


25 


40 11 


24 


37 


26 


41 3 


26 


30 


27 


57 


27 


42 24 


27 


51 


27 


43 18 


27 


45 


27 


44 13 


28 


39 


26 


45 6 


27 


33 


27 


46 


27 


28 


28 


54 


26 


47 20 


26 


47 


27 


48 11 


24 


37 


26 


49 3 


26 


54 


51 


50 19 


25 


43 


24 


51 8 


25 


33 


25 


58 


25 


52 23 


25 


48 


25 


53 15 


27 


42 


27 


54 12 


30 


42 


30 


55 14 


32 


46 


32 


56 20 


34 


57 10 





ft*-: 



. 27-27 
. 30-00 
. 31-03 
.32-14 
. 33-33 

34-61 






i-'^ 36-73 



. 34-61 
. 34-61 






33-33 






35-48 



. 36-00 
. 3600 
. 3600 
. 33-33 
. 33-33 
. 30-00 
. 30-00 
.28-12 
.28-12 
. 26-47 



ON RAILWAY CONSTANTS. 



237 



Consumption of Coke. 

616 pounds used to get up steam in the morning, 1 To be added in the se- 
and to fill up the firebox previous to starting J cond trip. 

Quantity of coke consumed during the trip of 95 miles, indu- 
sive of what was required to fill up the firebox at the end of 
the journey 3654? 

Coke consumed per mile 

Ditto per ton per mile upon the load (nett) 



lbs. 
38-4 lbs. 
■55 lbs. 



Intervals. 


Dist. 
in 

miles. 




Water 


Water evaporated. 






evaporated. 


Per mile. 


Per hour. 


From Liverpool to Warrington... 
Warrington to Crewe 


18 
24 

24f 
14| 
13i 




Gallons. 

393 
555 
519 
396 
245 


Gallons. 

21-83 
23-12 
20-97 
26-84 
18-15 


Cubic ft. 


337 cubic ft. water 
evaporated by 3654 
lbs. coke = 1 cub. 
ft. water per 10-84 
lbs. coke. 


Stafford to Whampton 

Whampton to Birmingham 




95 


' 


2108 


22-19 


93-2 





Statement of the time occupied in performing a trip from Liverpool to Bir- 
mingham, 95 miles, on an average rise of 1 in 2462, and of the time lost 
in stoppages and slackening and getting into the speed at the Stations. 



h m s 

Started ftoni Liverpool 10 28 121 .^^j^^;^^ ^f 

Arrived in Birmingham a 57 lOJ 



TIME LOST ON THE ROAD. 

Gettins; up speed at Liverpool, H to 4 miles, = 2} miles ... 
At full speed would have been 

Slackened speed at Sutton, &c., 11|- to 14^ miles, = 3^ miles... 
At full speed '. 

Stoppage, &c. at Warrington, 19| to 21J miles, = 2 miles .. 
At full speed 



Stoppage, &c. at Hartford, 31 J to 33i miles, =■ 2 miles 
At full speed 



Stoppage, &c. at Crewe, 43^ to 45^ miles, = 2 miles ... 
At full speed 

Slackened at Whitmore, 53 j- to 55 ,| miles, = 2 miles ... 
At full speed 

Stoppage, &c. at Stafford, 67} to 69J miles, =- 2 miles 
At full speed 

Stoppage, &c. at Whampton, 83 to 85 miles, = 2 miles 
At full speed 

Slackened at Birmingham, 96 to 96| miles, = 2 miles... 
At full speed 



s 

41 

20 

8 
51 

4 
16 

34 


8 
56 

34 


33 
4 




24 




Lost. 



21 
17 
48 
34 
12 
34 
29 

24 



Time which would have been occupied if the Train had started from 
Liverpool at full speed, and travelled from thence to Birmingham with- 
out stopping 



19 



39 



19 



Equal to an average speed of 28*60 miles per hour. 

Up an average rise of 1 in 24'62. 

Time, exclusive of dead stoppages, 3 hours 37 minutes. 



238 



REPORT — 1841. 



" Hecla," Tender and Twelve Carriages. 
From Birmingham to Liverpool. 



g 


4 

o 


Times. 


S 

Si 


u 


u 

w 3 


i 


1 


o 

rv 


Times. 


i 


i! 


at 

&>; 

in 3 




1 


s 




« 


Sg 


<u o 


Qi 


2 


& 




s 


^J 




o 


o 


s 




» 


q« 


s 


K 


o 


1 




R 


p" 


s 


tf 




h m s 












h m s 












" 


4 47 30 












fl4 


5 18 20 


41 




21-95 






1 


49 '27 












1 


55 


35 




25-71 


C 

o 




1 


50 19 


52 




17-30 








22 8 


• >> 






stop, g- 


Fall 


2 


58 


39 




2307 








23 12 








Start, g 


sir ' 


3 


51 32 


34 




26-47 






2 


24 3 








It 


2 


52 4 


32 




28-12 






3 


43 


40 




22-50 


> 




1 


33 


29 




31-03 






15 


25 19 


36 




25-00 


1 




2 


53 


27 




32-73 






1 


52 


33 




27-27 






3 


28 


28 






2 


26 22 


30 




30-00 






'- 3 


55 


27 




32-73 






3 


50 


28 




3214 




Level ■ 


1 


54 23 


28 






16 1 


27 41 


51 




35-30 






2 


51 


28 




32-14 






2 


28 7 


26 




34-61 






" 3 


55 20 


29 




3103 






3 


33 


26 


W5 


36-75 






4 


50 


30 




30-00 






17 


56 


23 


/^ 






1 


56 21 


31 




2903 






1 


29 20 


24 


J \#'l 








2 


53 


32 




28-12 




Fall 


2 


44 


24 










3 


57 25 


32 




28-12 




1 • 

330 


3 


30 8 


24 










5 


57 


32 




28-12 




18 


32 


24 










1 


58 30 


33 










1 


56 


24 










2 


59 2 


32 










2 


31 19 


23 










3 


32 


30 










3 


45 


26 










6 


5 6 


34 










19 


32 8 


23 








Rise 


1 
2 


39 
1 13 


33 
34 










1 
2 


32 
56 


24 
24 




37-41 




3 


47 


34 










3 


33 20 


24 


IM 






1 

532 


7 

1 


2 20 
53 


33 
33 










20 

1 


44 
34 9 


24 
25 










2 


3 25 


32 




27-35 






2 


32 


23 










3 


58 


33 






3 


56 


24 










8 


4 30 


32 


CO 








21 


35 19 


23 










1 


5 3 


33 










1 


44 


25 










2 


35 


32 










2 


36 9 


25 










3 


6 9 


34 










'- 3 


33 


24 


«5 


36-75 






9 


42 


33 










22 


58 


25 


--* 






1 
2 


7 16 
49 


34 
33 








Fall 


1 
2 


37 23 
47 


25 
24 


in 


36-75 






3 


8 22 


33 








?io ■ 


3 


38 12 


25 










10 


55 


33 


, 








23 


38 


26 




35-64 






1 


9 28 


33 










1 


39 4 


26 


>h 








2 


10 1 


33 


•s? 


27-27 






2 


28 


24 


<N 








3 


34 


33 










'' 3 


54 


26 . 




34-61 






11 


11 10 


36 


■ 








24 


40 20 


26 . 


• . • * * 


34-61 




Rise 


1 
2 


46 
12 22 


36 
36 








Level. 


1 
2 


48 
41 13 


28 
25 




33-97 




sru 


3 
12 


57 
13 33 


35 
36 


® 


25-07 






3 
= 25 


38 
42 6 


25 

28 


«5 

•5b 


33-97 






1 


14 10 


37 


• Its 






1 


32 


26 . 




34-61 






2 


45 


35 










2 


57 


25 . 


■ ■*• • 


36-00 






3 
13 


15 22 

58 


37 
36 








Rise 
I ■ 

4 n (1 


3 
26 


43 21 
46 


24 
25 


1{S 


36-75 




Level - 


1 
2 
3 


16 33 

17 7 
39 


35 
34 
32 




26-47 
28-12 




^*j \j 


1 
2 
27 


44 10 
35 

45 23 


24 
25 

48 . 


»5 


36-75 
37-50 





ON RAILWAY CONSTANTS. 

Table (continued). 



239 



c 


"w 






IK . 


« 3 


M 


c 


i 




i 


u 


1-1 


i 




s* 


Times. 


CJ 


£^ 


rzxi 


B 


3 


c. 


Times. 




t^ 


<u o 


a 


2 






iS 


iSi- 




5 


s 




ffi 


ias; 


Sir, 


i 


o 


s 




fi 


Q n 


a 


W 


o 


S 







Q« 


p. 


K 




h m 3 












h m s 










Level ■ 


1 

2 


5 45 48 
46 14 


25 
26 




36-00 
34-61 






1 
2 


6 20 28 
21 2 


34 
34 


}" 


26-47 






■ 3 


40 


26 




34-61 






3 


36 


34 


l 








28 

1 


47 7 
33 


27 
26 




33-97 




Rise 

1 ■ 

390 


42 

1 


22 12 

45 


36 
33 




26-28 




Fall 


2 


48 1 


28 




32-14 




2 


23 19 


34 








1 1 


3 


31 


30 




30-00 




3 


54 


35 




25-71 




(35 




49 35 


<•> 






stop. 1 
Start, a 




43 


24 51 


57 






i 






52 


>•• 











25 5 








stop. 1 




291 


54 1 














27 52 








Start. 2 




' 2 


59 


58 




15-51 






1 


29 44 












3 


55 44 


45 




20-00 






2 


30 44 


60 




15-00 






30 


56 24 


40 




22-50 




Level 44 


32 9 


85 




21-16 




Rise 


1 


57 6 


42 




21-43 






f 1 


43 


34 




26-47 




1 ■{ 


2 


42 


36 




25-00 






2 


33 14 


31 




29-03 




2] 05 


3 


58 17 


35 




25-71 






3 


44 


30 




30-00 






31 


50 


33 




27-27 




Fall _. 


45 


34 12 


28 




32-14 






1 


59 22 


32 




28-12 




330 


1 


38 


26 




34-61 






2 


53 


31 


i 








2 


35 5 


27 




33-33 






- 3 


6 24 


31 


^s 


29-03 






3 


31 


26 




34-61 






32 


55 


31 










r46 


56 


25 




36-00 






2 


1 57 


62 




29-03 






1 


36 20 


24 




37-50 






3 
33 


2 27 
59 


30 
32 




29-03 






2 

3 


43 
37 6 


23 
23 




39-13 
39-13 






1 


3 30 


31 










47 


28 


22 


■* 








2 


4 1 


31 








Fall 

1 -■ 


1 


50 


22 










3 


33 


32 








2 


38 13 


23 








Rise 


34 


5 4 


31 








T77 


3 


35 


22 


t^ 






1 

505 


1 


34 


30 










48 


56 


21 


1 W 


41-32 






2 


6 6 


32 










1 


39 18 


22 


01 








3 


37 


31 




28-75 






2 


39 


21 










35 


7 9 


32 


CO 








3 


40 1 


22 










1 


40 


31 










49 


22 


21 










2 


8 12 


32 










f 1 


44 


22 




40-91 






3 


43 


31 










2 


41 7 


23 


- 








36 


9 15 


32 










3 


31 


24 










1 


46 


31 










50 


54 


23 










' 2 


10 17 


31 










1 


42 16 


22 


\^^ 


39-13 






3 


48 


31 


reo 


29-03 




Fall ^ 


2 


39 


23 










37 


11 19 


31 








3 


43 4 


25 








Rise 

1 i 


1 

2 


51 
12 22 


32 
31 


in 

. 05 


28-56 




2 65 


51 

1 


25 
47 


21 
22 


~ 






(i5 


3 


53 


31 










2 


44 10 


23 










38 

1 


13 24 
55 


31 
31 


■« 


29-03 






3 

52 


33 
56 


23 
23 


.05 


39-13 






2 


14 26 


31 










r 1 


45 20 


24 










r 3 


58 


32 




28-12 






2 


43 


23 










39 


15 30 


32 




28-12 




Fall 


3 


46 7 


24 










1 


16 3 


33 








1 1 


53 


31 


24 


37-50 




Rise 


2 


35 


32 








53TT 


1 


47 1 


30 




30-00 




1 ■* 

5 iJO 


3 

40 

1 


17 9 
42 

18 15 


34 
33 
33 


.00 
03 


27-27 






2 


45 
48 20 
51 45 


44 




20-45 


Stop. 1 
Start. £ 


Rise 


r 3 


48 
19 21 


33 
33 




27-27 




Level < 


54 

1 


53 55 

54 40 


45 . 




20-00 




791? 


41 


54 


33 


■05 






2 


55 19 


39 . 




23-07 


















L 3 


63 


34 . 




26-47 





240 



REPORT — 1841. 

Table (continued). 









. 


1 


1 




g 

1 




2i 


Times. 


o 


<• 




Q 



S5 






i 


Ut3 


c 


^ 












4) O 




1. M 


:=j:: 




S 


is 


SS! 


E 


Q 


• & 


K 




27-27 
2903 



Level, 



32-14 
3214 
33-33 
33-33 
36-00 
34-61 



33-33 
33-97 
34-61 




33-33 
34-61 
35-30 



2500 
24-32 
21-95 
23-68 
26-47 
27-27 
2903 
30-00 
30-00 
31-03 
32-14 
31-03 
31-03 



ON RAILWAY CONSTANTS. 



241 



Table {continued). 



i 




i 


s^ 


»^ 




. 








if 


it 




Times. 


g 


S» 




.:4 


0) 


s 

04 


Times. 


<u 


Chi: 

w :3 


«j 




1 


'S^ 


3o 

~J5 


s 


« 






!^ 


^a 




S 




Q 


Q'" 


s 


K 


o 


§ 




s 


p" 


S 



Rise 

XI 

1 

Hi) 



Level 



86 



87 



h m 

8 23 12 
47 

24 33 

25 27 

26 32 
28 1 

8 29 17 
30 7 



31 
35 
46 
54 
65 
89 
76 
50 



29-03 
25-71 
19-56 
16-66 
13-84 
10-11 
11-84 
18-00 



Slipping. 

* 



Lev^l 

IX 
VI 

Rise 

]_ 

n 



88 



91 



95 



8 30 50 

31 28 

32 5 

39 58 

40 30 

41 
51 



43 
38 
37 

7-53 
32 
30 

10-0 



20-93 
23-68 
24-32 

20-93 
28-12 
30- 
25- 5 



Stopped, 



* Interrupted by overtaking Liverpool and Manchester Train. 



Consumption OF Coke. 

lbs. 
Used during the trip of 95 miles, exclusive of what would "1 
have been required to fill up the firebox at the end of the > 2790 

journey J 

Add the quantity of coke at first put in to get up steam and 1 p, „. 
fill the firebox J 

3406- 

Coke consumed per mile • . 35*8 

Coke consumed per ton per mile . '51 



Consumption of Water. 



Intervals. 






Water 
evaporated. 


Water evaporated. 




Per mile. 


Per hour. 


From Birmingham to Wolver- 1 

hainpton J 

Wolverhampton to Stafford 
Stafford to Crewe 


13i 

14i 

241 

24 

18 


Rise. 

Fall. 

Rise & Fall. 

Fall. 


Gallons. 

311 

244 
452 
439 
427 


Gallons. 

23-04 

16-54 
18-26 
18-29 
23-72 


Cubic feet. 


300 cubic feet of 
water evapo- 
rated by 34-06 
lbs. of coke. 

=1 cubic foot of 
water, by 11-35 
lbs. of coke. 


Crewe to Warrington 

Warrington to Liverpool... 

Total 




95 




1873 


19-71 


85-7 







i 



1841. 



242 



REPORT— 1841. 



Statement of the time occupied in performing the trip from Birmingham 
to Liverpool, 95 miles, down an average descent of 1 in 24*62, and of 
the time lost in stoppages, and slackening and getting into speed at the 
Stations. 



h m 

Started from Birmingham 4 47 

Arrived in Liverpool 8 51 



s 

301 
^ 'f inclusive of stoppages 



TIME LOST ON THE ROAD. 

Getting up speed at Birmingham, | to 2| miles, = 2 miles... 
At full speed would have been 

Stoppages at Wolverhampton, 13f to 15 J miles, = 2 miles. . . 
At full speed 

Stoppages, &c. at Stafford, 28^ to 31^ miles, = 3 miles 

At full speed 

Stoppages, &c. at Whitmore, 42^ to 44^ miles, = 2 miles ... 
At full speed 



Stoppages, &c. at Crewe, 53 to 55| miles, = 2^ miles 
At full speed 



Stoppages, &c. at Warrington, 77J to 79 J- miles, = 2 miles . 
At full speed 



Delay arising from overtaking Train on Liverpool and Man- 
chester Line, 87f to 95f miles, = 8 miles 

At full speed 



5 58 

3 40 

9 11 

4 

11 52 

6 

9 55 
4 16 

10 55 
4 20 

30 16 
4 

20 10 
16 



2 18 
5 11 
5 52 

5 39 

6 35 
26 16 

4 10 



Time which would have been occupied if the Train had started from Bir- 
mingham at full speed, and travelled from thence to Liverpool without 
stopping 



h m s 
4 3 30 



56 1 



3 7 29 



Equal to an average speed of SO-'iO miles per hour. 

On an average descent of 1 in 2462. 

Time, exclusive of dead stoppages, 3 hours and 30 minutes. 



Table of the uniform speeds attained by the "Hecla," with a load consisting 
of the Tender and Twelve Carriages (=70 tons, gross) on the several 
Gradients of the Grand Junction Railway. 



Gradient. 


Uniform Speed. 


Mean. 


Remarks. 


Liverpool to 
Birmingham. 


Birmingham 
to Liverpool. 


Rise, 1 in 96 
1 in 177 
1 in 265 
1 in 330 
1 in 390 
1 in 400 


Miles per 
hour. 

13-63 
22-25 

24-87 
25-45 

26-47 


Miles per 
hour. 

25-07 
26-28 


Miles per 
hour. 

22-25 

24-87 
25-26 
26-28 


Speed not uniform. 



ON RAILWAY CONSTANTS. 

Table {continued). 



243 



Gradient. 


Uniform speed. 


Mean. 


Remarks. 


Liverpool to 


Birmingham 




Birmingham. 


to Liverpool, 








Miles per 


Miles per 


Miles per 






hour. 


hour. 


hour. 




1 in 400 


27-27 





26-87 




1 in 505 




28-75 


28-75 




1 in 532 




27-35 


27-35 




1 in 590 




27-27 


27-27 




1 in 650 




29-03 


29-03 




Ijcvel 


30-71 


31-15 
32-79 


30-93 
32-79 


r First starting, and in 


Fall, 1 in 3474 


1 in 1094 


34-6i 







■1 better than average 


lin 650 


32-58 




32-58 


order. 


lin 590 


3316 




33-16 




1 in 532 


34-30 




34-30 




1 in 505 


31-36 






Bad coke. 


1 in 440 




35-64 


35-64 




1 in 400 




36-75 


36-75 




1 in 330 


36-73 


37-41 


37-07 




1 in 265 




39-13 


39-13 




lin 177 




41-32 


41-32 





The principle of compensation will be however more directly tested by 
taking the mean speed in ascending each gradient, and the mean speed in de- 
scending them respectively, and comparing together the means of these se- 
verally with the mean speed on the levels. This is done in the following 
table : — 



Gradient. 


Speed. 


Mean. 


Ascending. 


Descending. 


One in 

177 

265 
330 
400 
532 
590 
650 


Miles per 
hour. 
22-25 
24-87 
25-26 
26-87 
27-35 
27-27 
29-03 


Miles per 
hour. 
41-32 
39-13 
37-07 
36-75 
34-30 
33-16 
32-58 


31-78 
32-00 
31-16 
31-81 
30-82 
30-21 
30-80 






Level... 


30-93 



These results render it quite apparent that the gradients do possess the 
compensating power ascribed to them. The discrepancy existing among 
the mean values of the speed, is nothing more than what may be ascribed 
to casual variations in the moving power. This experiment also was made 
under very favourable circumstances, the day being quite calm. Without 
going into the details of the principle on which these remarkable results de- 
pend, it may be stated generally, that since the chief part of the resistance 
of a railway train depends on the atmosphere, and is proportional to the 
square of the velocity, a very small diminution in the velocity itself produces 
a considerable diminution in its square. A train, in ascending a gradienti 

r2 



244 ' REPORT — 1841. 

may therefore relieve itself from as much atmospheric resistance as is equal 
to the gravitation of the plane by slackening its speed. If its speed be 
slackened so as to render the resistance equal to that which it would have 
upon a level, then the engine would have to work with a less evaporating 
power than on a level, inasmuch as the motion would be slower. In practice, 
therefore, it never can be needful to slacken the speed so much as to equalize 
the resistance with that upon the level. Supposing the evaporating power 
to remain the same, the speed need only be slackened, so that with the same 
evaporation an increased resistance can be overcome at a speed less than 
the level, but not so much less as would render the resistance equal to the 
level. This, in fact, is what takes place in practice, as is apparent from the 
results above given. 

By comparing the average evaporation effected in the above experiment 
with the average speed, an approximate value of the mean pressure of steam 
on the pistons may be obtained. 

Let L = the stroke of the piston in feet, 
A = the area of the piston in square feet, 
n = the number of Strokes of the piston per minute, 
••• 2 ?i A L = the number of cubic feet of space through which the piston 
moves per minute. 

Let c L A = the clearage, or the space between the steam-valve and the 
piston at each end of the stroke, 

•.• the volume of steam admitted to each cylinder through the steam-valve 
at each stroke will be 2 w A L (1 + c). 

Let W = the water in cubic feet admitted per minute in the form of steam 
to each cylinder, 

Let S = the number of cubic feet produced by a cubic foot of water at 
the density which the steam has in the cylinders, 

Hence we shall have WS = 2wLA(l +c). 

And if P = the pressure of steam in the cylinder in lbs. per square foot, 
we shall have -^ ^ ^ 

p= "^ " h 

2«LA(l+c) 

where a = 4347826 and 5 = 618. 

In the present case we have L = 1-5, A = 0"853. Let us take c = 0'05. 

The mean rate of evaporation per hour was 89'5 cubic feet of water. The 
rate per minute would then be P-iQ cubic feet. Hence, since half the steam 
is supplied to each cylinder, we shall have W = 0"745. 

The mean speed of the train being 30'93 miles per hour, the velocity in 
feet per minute was 2722. To find the velocity of the piston, this must be 
reduced in the ratio of the circumference of the driving wheel to twice the 
length of the stroke. But the driving wheel being 5 feet in diameter, its cir- 
cumference will be 15*7 feet; and since 2L = 3, the velocity of the piston 
will be q 

2722 X -4-= 520; 
15-7 



and the value of n will therefore be 
Hence we obtain 



« = -5^ = ^= 173-3. 
2L 3 



P = 0-74-5 X 4347826 ^^g ^ gg,^. 

346-6 X 1-5 X 0-853 x 1-05 

* See Lardner on the Steam-Engine, 7th edit., p. 514, 



ON RAILWAY CONSTANTS. 245 

Hence the pressure per square inch was 46 lbs. If 14*5 lbs. be deducted for 
the atmosphere, there will remain 31*5 lbs. per square inch to overcome all 
the resistances, including those of the engine itself. 

The sura of the areas of the pistons being 246 square inches, the total 
pressure upon them, after deducting the resistance of the atmosphere, was 
246 X 31*5 = 7749. If we allow 2 lbs. per square inch to represent the re- 
action of the blast pipe, the effective pressure will be 7257 lbs. This reduced 

o 

to the contact of the driving-wheels with the rails by multiplying it by » 

15*7 
will give 1386 lbs. as the whole tractive force expended on the gross load. 

If 1 50 lbs. be deducted from this as representing the force expended on the 
engine itself, there will remain 1236 lbs. to represent the actual force ex- 
pended in drawing the train, including the tender. 

The weight of the train, including the tender, being in this case 70 tons, 
the ratio of the weight to the gross resistance will be 126 to 1, and conse- 
quently that will represent the mean angle of repose for a train of this mag- 
nitude moved at 31 miles an hour. 

It may be useful to form an approximate estimate of the proportion in 
which the total tractive force of 1236 is distributed between the different 
sources of resistance. If we take the friction according to the results of the 
experiments detailed in the first part of this Report to be at the rate of 5'5 lbs. 
per ton of the gross weight of the load, the total amount of the friction of 
the train of twelve coaches and tender, weighing 70 tons, will be 385 lbs. 
Thus we shall have — 

Friction proper of the load ..... 385 lbs. 
Atmospheric resistance 851 do- 
Total resistance 1236 do. 

It follows, therefore, that this train of twelve coaches, engine, and tender, 
moving down an inclined plane falling at the rate of 1 in 120, with a velocity 
of 30*90 miles an hour, would not be accelerated, and that to move it down 
planes of less inclination at the same speed would require an amount of trac- 
tive power to be exerted by the engine, which would depend on the inclina- 
tion of the plane. 

It was found in this experiment, that the mean evaporating power of the 
coke was at the rate of 1 cwfr. of coke to 10 cubic feet of water, or ll"21bs. 
of coke per cubic foot of water. This consumption of fuel does not greatly 
exceed the common estimate for the consumption of coal in ordinary low- 
pressure boilers. 

The results of this experiment are quite in accordance with those of all 
the other experiments which have been stated in this Report. Lighter and 
smaller trains, moving with the same speed, suffered greater resistance in 
proportion to their weight, or what amounts to the same, they acquired less 
speed with the same resistance. 

Taking the same estimate of the friction proper, the following table ex- 
hibits the total resistances to which trains of different magnitudes were found 
in these experiments to be subject when moving at the speeds given in the 
fourth column, and the proportion in which these resistances are due to the 
different resisting influences respectively : — 



246 



REPORT — 1841. 



Description of Train, 


Weight. 


Wind. 


Speed. 


Friction 
proper. 


Atmo- 
spiieric 

resist- 
ance. 


ToUl 
resist- 
ance. 


Twelve coaches and tender . 
Eiffht coaches 


tons. 

70 
40| 
40f 
34i 

27i 

m 

27i 

27i 

20^ 

20i 

20 

18 

18 

15i 


Calm 


m.perh. 

31 

SH 

26^ 

35^ 

37i 

34i 

321 

27i 

38i 

23 

19 

33f 

2H 


lbs. 
385 
225 
225 
190 
151 
151 
151 
151 
114 
114 
110 
100 
100 
85 


lbs. 

851 
800 
291 
678 
404 
374 
404 
374 
402 
145 
59 
321 
127 
279 


lbs. 

1236 
1025 
516 
868 
555 
525 
555 
525 
516 
259 
169 
421 
227 
364 


Dead calm ... 
Fair wind .... 
Calm 


T^ifht coaches 


Six coaches 




Fair wind .... 
Fair wind .... 
Adverse wind 
Adverse wind 
Fair wind.... 
Fair wind.... 
Fair wind .... 
Fair wind .... 
Fair wind. ... 
Fair wind .... 


Six coaches 


Six coaches 






Four coaches 


Four coaches 


Four coaches 




Four coaches 





Upon a general view of the body of experimental researches which have 
been detailed in this Report, the following practical conclusions appear to be 
fully established : — 

1 . The resistance offered to the moving power by a railway train is not, as 
has been heretofore supposed, independent of the speed, but is augmented in 
a high proportion as the speed is increased. 

2. If the carriages be unaltered in number, form, and magnitude, the re- 
sistance will be in the simple ratio of the load, the speed and other circum- 
stances being the same. 

3. If the train be increased by augmenting the number of carriages, the 
ratio of the resistance to the weight at the same speed, other things being the 
same, will be diminished. 

4. The practice hitherto adopted of expressing the resistance on railways 
as so man^ pounds per ton of the gross load ought to be discontinued, since 
the resistance is not proportional to the gross load, and therefore such ex- 
pression may lead to erroneous conclusions. 

5. The resistance of ordinary loads transported on railways at ordinary 
speeds, more especially of passenger trains, is very much greater than has 
been heretofore assumed, being with heavy loads at least double the common 
estimate, and with light loads threefold greater. 

6. That a considerable amount of the resistance, more especially in the 
case of passenger trains, is due to the resistance of the air, and therefore 
expedients (such as wheels of increased magnitude) to diminish the amount 
of the mechanical resistances are not likely to be attended with adequate 
advantage. 

7. That the resistance due to the air appears to proceed from the effect of 
the entire volume of the train, and not to depend in any sensible degree on 
the form of its foremost end. Expedients, therefore, for attaching a sharp 
front to the engine are ineffectual and useless. 

8. That the mathematical formulae given in the first part of this Report, 
consisting of two parts,^ — one proportional to the gross weight of the load but 
independent of the speed, and the other proportional to the square of the 
speed — have given results in all the cases to which they have been applied 
in accordance with the experiments. Such formulse may therefore be taken 
to represent the facts until further and more extended and varied experience 
shall show the corrections of. which they may be susceptible. 

9. That the resistance produced to railway trains moving at ordinary speeds, 



ON RAILWAY CONSTANTS. 24? 

by curves of a mile radius, is inappreciable, and therefore curves of a much 
shorter radius may be safely laid down. 

10. That the mean amount of resistance to railway trains being so much 
above the estimate heretofore adopted by engineers, and the resistance from 
curves being so much less than their estimate of it, the practical principles 
on which they have generally acted in laying out lines of railway will require 
serious modifications, all of which fortunately will have a tendency to diminish 
the expense and difficulty attending the construction and the working of rail- 
ways. 

In consequence of the low estimate of the resistance and the high estimate 
of the effect of curves, which engineers in general have heretofore adopted, 
great expense has been incurred and difficulties encountered to obtain flat gra- 
dients and straight lines. In some cases the gradients have been so levelled as 
not to exceed from four to six feet per mile, and the lines have been rendered 
so straight, that the curves nowhere have so short a radius as a mile. From 
what has been proved in the present Report, it is evident that such lines of 
railway will afford no practical advantage over those which have been laid 
down with gradients of sixteen, twenty, or even twenty-five feet per mile, and 
on which curves of a mile or less radius have been allowed. 

The writer of this Report cannot conclude it without acknowledging the 
liberal assistance he has received from the Grand Junction Railway Com- 
pany, who supplied engines, carriages, and waggons, without charge, for the 
experiments ; also from the Liverpool and Manchester Railw'ay Company, who 
allowed many of the experiments to be made on their line. 

Mr. Hardman Earle of Liverpool, has also been of the greatest assistance 
in conducting the experiments, several of which were suggested by him. 

Similar acknowledgements are also due to Mr. Edward Woods, engineer to 
the Liverpool and Manchester Railway Company. This gentleman super- 
intended and directed many of the most Important experiments, and subse- 
quently reduced and tabulated them, when the writer of this Report was pre- 
vented by professional business from being present. 



Report on Railway Constants. By Edward Woods. 

In the first Report, by Dr. Lardner, of the Committee appointed by the 
British Association to investigate the mean values of the resistance of trains 
moving upon railways, published in the eighth volume of the Transactions 
of the Association, the various modes proposed for ascertaining the amount 
of resistance to the tractive power were described, and their relative merits 
discussed. 

The methods alluded to were — 

L By the dynamometer. 

2. By observing the motion of a load down an inclined plane, sufficiently 
steep to give accelerated motion. 

3. By putting the load in motion on a straight and level line of railway, so 
as to impart to it a certain known velocity, and then observing the rate of 
its retardation. 

4. By a combination of the two preceding methods, as resorted to by Le 
Comte de Pambour. 

5. By a plan proposed by Dr. Lardner, viz. selecting two inclined planes of 



248 REPORT— 1841. 

different acclivities, and observing the maximum loads which an engine can 
draw up those planes whilst exerting an equal tractive power. 

At the time of the publication of their first Report the Committee had 
made a number of experiments in accordance with the second method, — that 
of observing the motion of trains down inclined planes of different degrees of 
acclivity, noting whether the motion were accelerated, uniform, or retarded. 
Althougli these preliminary experiments were limited in number, and tried 
under rather disadvantageous circumstances as respected the weather, the fact 
that resistance increased in a heretofore unsuspected degree, in proportion as 
the speed of the train increased, was satisfactorily established. In what ratio 
the increment tooii place, whether as the square or some other function of 
the velocity, could not be determined, the results presenting some trifling 
apparent discordances, in consequence of the varying effect of the wind which 
prevailed at the time of the experiments. In pursuing their inquiries at a 
subsequent period, the Committee have been more fully convinced of the 
soundness of the principle which guided them in the selection of the method 
they at first adopted, and they have accordingly continued to conduct their 
experiments in a similar manner, repeating them with various sizes of trains, 
at various velocities, on the Sutton incline of 1 in 89 on the Liverpool and 
Manchester Railway, and on the inclines of 1 in 177, 1 in 265, and 1 in 330, 
on the Grand Junction Railway. 

It is to be regretted that the weather was not on all occasions perfectly 
favourable. In some instances, however, there was not a breath of wind to 
disturb the results, especially when engaged at the Sutton incline plane. 
Such results deserve great confidence, and are particularly valuable for de- 
termining the amount of friction, properly so called. 

A few remarks are necessary on the principle of analysis, adopted with re- 
gard to the observations which appear in a tabular form at the end of this 
Report. The data given there or elsewhere in the Report are, — 

1. The coefficient of gravity on the inclination of the plane. 

2. The initial velocity of the train at some determinate point on that plane. 
This may be either zero, as when the train starts from a state of rest, or some 
positive quantity. 

3. The terminal velocity at some other detei-minate point on the same plane. 

4. The time elapsed in traversing the space intervening between those two 
points. 

5. The space intervening. 

6. The force of gravitation, which in this latitude is known to be repre- 
sented by 32^, the velocity in feet per second acquired by a body falling 
freely in vacuo, at the end of the first second. 

1. The weight or mass of the train, exclusive of the wheels and axles. 

8. The weight or mass of the train subject to rolling motion, viz. the wheels 
and axles. 

9. The radius of the wheels. 

10. The distance from the centre of the wheel to the centre of oscillation. 
From these data, when accurately obtained, the resistance of the train can 

be determined with absolute precision, the method turning altogether upon a 
comparison between a certain fixed and standard force, the force of gravita- 
tion, and the observed force by which the train is impelled in its descent. If 
a body move down an inclined plane without encountering resistance, its ve- 
locity at any given depth below the level of the point where its motion first 
commences will be always equal to the velocity it would have acquired by a 
free vertical descent, through the same height. If, then, this standard velocity 
be compared with the qbserved velocity of a body which has moved down a 



ON RAILWAY CONSTANTS. 249 

similar inclined plane to the same point, but which does meet with resistance 
in its passage, we at once obtain the means of assigning what amount of re- 
sistance it has suffered. 

Some persons have objected to this method, on the ground that. the results 
hitherto obtained by it have not always been consistent with each other. 
Such inconsistencies, however, may be satisfactorily explained, either on the 
supposition of the data not having been correct, or, what is more probable, 
from the fact of the existence of unobserved causes of irregularity, such as 
the influence of favouring or adverse winds, and differences of friction of the 
carriages. It will hereafter be shown what a remarkable correspondence the 
motions of the same train exhibit when permitted to descend along the same 
plane from the same point of elevation, provided the atmosphere be perfectly 
calm. Such correspondence could only exist under the uniform operation 
of the same producing cause, and the absence of accidental causes ; and we 
therefore conceive that no surer test can be applied to determine the mean 
resistance experienced by a train in moving from one point to another down 
an uniform inclination, than a comparison between the observed time of its 
passage and the time it would have occupied if resistance had been altogether 
removed. 

There are three cases of the motion to which the same formula is equally 
applicable : — 

1. When the motion is accelerated. 

2. When the motion is uniform. 

3. When the motion is retarded. 

In the first case the coefficient (determined by the inclination of the plane) 
of gravity is greater than the coefficient of resistance, and therefore the quan- 
tity which must be added to the coefficient of gravity to represent the coeffi- 
cient resistance is negative. 

In the second case the coefficient of gravity is equal to the coefficient of 
resistance, and no correction is required. 

In the third case the coefficient of gravity is less than the coefiicient of 
resistance, and the addition to the coefficient of gravity is a. positive one. 

In all cases therefore the coefficient of resistance may be found, by adding 
to the coefficient of gravity a quantity (determined by considerations alluded 
to in the former Report) which is either negative, or equal to zero, or positive. 

This quantity may be thus obtained : — Multiply the initial velocity (2) in 
feet per second by the time in seconds (4). From this product subtract the 
space (in feet) passed over (5), and divide the difference by 16j2 times the 
square of the time occupied (4). The quotient thus found must be subjected 
to a slight correction, owing to the rotation of part of the moving mass, which 
correction may be detei-mined by reference to data Nos. 7, 8, 9, and 10. 

The initial velocity multiplied by the time represents the space which the 
train would describe were that velocity to remain constant. In the case of 
imiform motion, the velocity does remain constant, and the product of the 
two numbers equals the space traversed. Their difference, and consequently 
the whole quantity dependent upon it, vanishes, and the coefficient of gravity 
becomes also the coefficient of resistance. 

In accelerated motion the product of the numbers is less than the space 
traversed, and the quantity to be added to the coefficient of gravity is nega- 
tive, indicating the amount by which the force of gravity exceeds that of the 
resistance. On the other hand, when the motion is retarded, the reverse 
takes place, and the quantity to be added is positive. 

Under the condition of uniform motion we are enabled positively to pro- 
nounce what is the mean resistance for that particular velocity. When, how- 



250 REPORT— 1841. 

ever, the velocity is accelerated or retarded between the two points of ob- 
servation, although the mean resistance is known, we cannot state whether 
that mean resistance is due to the mean velocity, or to some other velocity 
intermediate between the limits of the initial and terminal velocities, because 
experience has not yet assigned the law of the corresponding increments of 
resistance and speed. It will be sufficient for all practical, and even theo- 
retical purposes, to assume the mean resistance as applying to the mean ve- 
locity, remarking that the calculations are chiefly made from observations 
where the initial and final velocities do not widely differ, thus reducing, as 
far as possible, the limits of error. A more considerable source of error 
arises from the difficulty of obtaining with precision the initial velocity, 
owing to our inability to measure the time of passing from stake to stake 
accurately to a small fraction of a second. To obviate this, a mean has been 
taken from the observed times of traversing one or two spaces, preceding 
and succeeding the post at which the actual velocity is required. The errors 
are thus diffused over a larger space, and rendered less sensible. 

The carriages employed belonged either to the Grand Junction, or to the 
Liverpool and Manchester Company. The former were first class, the latter 
second class, but both kinds were closed at the top and sides, presented the 
same transverse section, were loaded to nearly the same gross weights, and 
in other respects were identical. It is next to impossible to obtain two car- 
riages even of similar make, whose friction shall be exactly the same, and 
accordingly a slight difference was observed, and it was found on the whole 
that the mean friction of the Grand Junction carriages exceeded the mean 
friction of the Liverpool and Manchester carriages, a fact which may be ac- 
counted for by the latter having been in use for a longer period. 

We shall now consider the results afforded by the tables under the follow- 
ing heads : — 

1 . The Evaluation of Friction proper. 

2. The additional resistance produced by increase of speed in trains of 
different sizes. 

3. The effect of modifying the form of frontage, and of otherwise altering 
the nature of the exterior surface of the train, as for instance, by closing up 
the spaces between the carriages, ascertaining also the effect of the engine (as 
regards its external configuration in diminishing the resistance). 

1. TJie Evaluation of Friction, properly so called. — On the 23 rd of August 
1839, the weather being perfectly fine and calm, three Liverpool and Man- 
chester first class carriages, weighing gross l^'S tons, were allowed to de- 
scend the Sutton inclined plane from a state of rest, starting from a post 
numbered 0, and urged only by the force of gravitation. The experiment 
was repeated four times, and the train descended the plane from to 22 post, 
a distance of 2420 yards, in the following times respectively : — 

1st. 4 m 28 s. 2nd. 4 m 25 s. 3rd. 4 m 23 s. 4th. 4 m 22 s. 

These results coincide so closely, that we may fairly consider the sum of 
the resistances to have been the same in all cases, or at any rate to have de- 
creased in only a very slight ratio, in proportion as the axles became better 
lubricated by continued running. 

The fourth experiment is chosen as the subject of calculation, to determine 
the resistance of the said carriages at very slow velocities. Five separate 
computations are made from observations of the times of descent from No. 
to No. 1, No. to No. 2, No. to No. 3, No. to No. 4, and No. to 
No. 5 posts respectively. 



ON RAILWAY CONSTANTS. 



251 



tons. 



The weight of the train, exclusive of wheels and 1 , ^ . 

axles, was equal to J 

The weight subject to rolling motion, viz. the wheels \ „ , 

and axles, was J 



Total 



14.-8 



The radius of the wheels was 18 inches, and the distance from the centre 
of the wheel to the centre of oscillation was 10 inches. In accordance with 
these data, the quotient alluded to, page 249, must be corrected by multiply- 
ing it into the constant number 1*09. 

Three Liverpool and Manchester First-class Carriages. 



No. 
Post to 


Time 
occupied. 


Space 
passed 
over. 


Coefficient 
of 

gravity. 


Coefficient 

of 
resistance. 


Resistance. 


Mean velocity. 


In lbs. 
per ton. 


Total. 


Feet 
per second. 


MUes 
per hour. 


1 

2 

3 
4 
5 


seconds. 

52 

73 

89 

104 

117 


feet. 
330 
660 
990 
1320 
1650 


•01098 
■01098 
•01098 
•01098 
•01098 


•00271 
•00259 
•00250 
■00271 
•00281 


6-07 
5^80 
5-60 
6-07 
6-29 


89^8 
85^8 
82^9 
89^8 
93^1 


6-34 

9-04 

1112 

1269 

1410 


4^32 
6^16 
7^58 
8-65 
9-61 



At these slow velocities the atmosphere would not offer much resistance, 
and we may therefore practically consider the resistances assigned to be those 
of friction alone. One remarkable result will not escape the attention, viz. 
that the resistance diminishes until the train attains the speed of 7*58 miles per 
hour, after which it again increases, owing no doubt to the opposition of the 
air at the higher mean velocity. At 4*32 miles per hour the resistance was 
6"07 lbs., whereas at 7'58 miles per hour it becomes only 5*60 lbs. per ton, 
showing a difference of ^ lbs. of a lb. per ton. This fact, it is believed, has 
hitherto been unnoticed. The cause is owing to a more perfect lubrication 
of the axles at the higher speed, and depends probably upon the formation 
of a certain thickness of film of grease between the brass step and the upper 
surface of the journal which keeps the two surfaces more effectually apart. 
In consequence of the slow velocity the pressure of the step upon the journal 
has a longer time to act in effecting the displacement of the fresh grease 
which has been supplied from the box, and the result is a greater amount of 
friction. 

We proceed to estimate the friction of the other description of carriages, 
viz. those belonging to the Grand Junction Company, and which were used 
in the experiments on the long planes of the Grand Junction Railway. 

On the evening of the 12th of July, 1839, a train of eight second-class 
Grand Junction carriages, weighing gross iO-lS tons, was brought to the 
top of the Sutton inclined plane, and allowed to descend from a state of rest 
from the post numbered 0, as in the previously mentioned instance. The 
weather was perfectly calm and fine. The carriages had been previously in 
use throughout the day on the Grand Junction line, and the experiments 
made with them will be hereafter noticed. It is sufficient to observe, that the 
friction of these carriages would be reduced to its minimum by the work 
they had undergone. 

The time of descent from to 22 post was •t'" 34=-25. As a check upon 
the results, an experiment made with the very same carriages, performed on 
the 8th July, and recorded in Table No. 6, may be referred to. In that in- 



252 



REPORT — 1841. 



stance, the time of descent through the same space was 4™ 5P, indicating a 
slightly increased amount of friction. It is not thought necessary to enter 
into a calculation of their friction on the 8th July, inasinuch as the perform- 
ances agree very closely; and with the view of comparison with other sets of 
experiments made on the same day, it is considered on the whole fairer to 
ascertain the friction on that day, viz. the 12th July. 

Five computations are made from observations of the times of descent 

from No. to No. 5 post. 

tons. 

The weight of the train, exclusive of wheels and axles, was S^'OS 

The weight subject to rolling motion, viz. the wheels and axles, was 6*40 



Total .... 40-45 
The radius of the wheels was 18 inches, and the distance from the centre 
of the wheel to the centre of oscillation, 10 inches. In accordance with these 
data, the coefficient of correction for the quotient alluded to, page 249, is 1'088. 

Eight Grand Junction Carriages = 40'45 tons. 



No.O 


Time 


Space 


Coefficient 


Coefficient 


Resistance. 


Mean resistance. 


Post 
to 


occu- 
pied. 


passed 
over. 


of 
gravity. 


of 
resistance. 


In lbs. 
per ton. 


Total. 


Feet per 
second. 


Miles 
per hour. 




seconds. 


feet. 














1 


55 


330 


•01098 


■00360 


8^06 


326-2 


6-00 


4-09 


2 


7; 


660 


•01098 


•00346 


7-75 


313^5 


8-57 


5-84 


3 


95 


990 


•01098 


■00356 


7^97 


322-5 


10-42 


7-10 


4 


110 


1320 


•01098 


•00360 


8-06 


326-2 


11-09 


7-56 


5 


123-5 


1650 


•01098 


•00366 


8^20 


331-6 


13-36 


9-11 



Here, as before, we find the friction diminishes, it being least when the speed 
averages 5*84 miles per hour. From both series of experiments we deduce 
the following conclusions, which will be adopted in the subsequent investiga- 
tions : — 

1. The friction was least when the train was moving at the rate of about 
6 miles per hour. 

2. The total resistance of the train was also least when moving at about 6 
miles per hour, notwithstanding the effect of the atmosphere at that speed. 

3. The mean resistance of the Liverpool and Manchester carriages was 
never less than 5-60 lbs. per ton. 

-i. The mean resistance of the Grand Junction carriages was never less 
than 7*75 lbs. per ton. 

We shall call the friction of the Liverpool and Manchester carriages equal 
to 6 lbs. per ton, and that of the Grand Junction carriages equal to 8 lbs. per 
ton, numbers which represent nearly the mean of the computed measures of 
friction. 

2. The second point of our inquiry is now to be considered, viz. the effect 
which accompanies an increased speed of the train, as regards the amount of 
resistance experienced. We shall first present an analysis of the experiments 
made on the Sutton plane when the air was perfectly calm. Some of these 
experiments have been before noticed and made use of for determining the 
friction of the trains, but all will be found detailed in the Tables numbered 
IV., v., VIL, VIIL 

To begin wij;h the train of three Liverpool and Manchester carriages, which 
descended the Sutton plane on the 23rd August, 1839 (see Table, No. IV.). 
The weight and other particulars have been stated before. The train having 
acquired considerable speed, was observed to pass posts Nos. 5, 10 and 15, at 



ON RAILWAY CONSTANTS. 



253 



the respective velocities of 27"50 feet, S^-TS feet, and 41*2,5 feet per second, 
the velocity having evidently been accelerated throughout. Three compu- 
tations have been made from these data, in connection with the time occu- 
pied in traversing the distances between the posts, distances equal to 1650 
feet in each case. The mean resistance having been computed, the mean ve- 
locity (found by dividing the distance in feet by the number of seconds oc- 
cupied in passing over) is placed opposite in the table, and it is to this mean 
velocity that the resistance is presumed to refer. 

Three Liverpool and Manchester Carriages = 14"8 tons. 



Ground of 
experiment. 


Time 
occu- 
pied. 


Space 
passed 
over. 


Initial 
velocity. 


Coefficient 

of 

gravity. 


Coefficient 

of 
resistance. 


Resistance. 


Mean velocity. 


In lbs. 
per ton. 


Total. 


Feet per 
second. 


Miles 
per hour. 


Post. 

5 to 10 
10 to 15 
15 to 20 


seconds. 
50 

43 

38 


feet. 

1650 
1650 
1650 


ft. per sec. 
27-50 

34-73 

41-25 


-01113 
•01113 
-01113 


•00367 
•00539 
-00726 


8-22 
12-07 
16-26 


1216 
178-6 
240-7 


33-00 
38-37 
43-42 


22-50 
26-16 
29-60 



The friction of the train of eight Grand Junction carriages was determined 
from an experiment on the Sutton incline (Table, No. V.). The resistance 
at higher speeds may be deduced from the same experiment. In this resist- 
ance, as in the case of the Liverpool and Manchester train, the carriages 
started from a state of rest, at No. post, and were accelerated to the foot of 
the plane. 

Eight Grand Junction Carriages = 40*4<5 tons. 



Ground of 
experiment. 


Time 
occu- 
pied. 


Space 
passed 
over. 


Initial 
velocity. 


Coefficient 

of 

gravity. 


Coefficient 

of 
resistance. 


Resistance. 


Mean velocity. 


In lbs. 
per ton. 


Total. 


Feet per 
second. 


Miles 
per hour. 


Post. 

5 to 10 
10 to 15 
15 to 20 


seconds. 

54-75 

43-5 

38-0 


feet. 

1650 
1650 
1650 


ft. per sec. 

25-26 
34-30 
40-84 


-01113 
•01113 
-01113 


-00505 
•00547 
•00654 


11-31 
12-25 
14-65 


457-6 
495-6 
592-6 


30-13 
37-93 
43-42 


20-54 
25-86 
2961 



Bearing in mind that the friction of the two sets of carriages were respect- 
ively determined to be 6 and 8 lbs. per ton, it will be seen how considerably 
the resistance has augmented with the speed. The resistance experienced by 
the train of three carriages, when moving at 22'5 miles per hour, became 8'22 
lbs. per ton; when at 26'16 miles per hour, 12"07lbs. per ton ; and when at 
29*6 miles per hour, 16"26 lbs. per ton, or finally, more thautdouble the re- 
sistance at 6 miles per hour. The resistance encountered by the train of 
eight carriages, when moving at 20*54 miles per hour, became 11 'SI lbs.; 
when at 25*86 miles, 12*25 lbs.; and when at 29*61 miles per hour, 14*65 lbs. 
Here the ratio of the increase was less, owing to the greater weight of the 
train. 

On the same evening, the 12th July, two other experiments were made 
with portions of the same train of cai'riages. A train of four carriages was 
provided, and after that a train of six carriages. These trains, instead of being 
allowed to descend quietly from the top of the plane, were impelled over the 
summit at the speeds of 33 and 26 miles per hour, by means of a locomotive 



254 



REPORT — 1841. 



engine, Avhich on reaching the post No. 0, ceased to propel. The force of gra- 
vitation afterwards accelerated the speed down the plane. An examination 
of the respective rates of acceleration will give the means of determining the 
resistances in each case. See Tables, Nos. VII. and VIII. 

Four Grand Junction Carriages = 20*45 tons. 



Ground of 
experiment. 


Time 
occu- 
pied. 


Space 
passed 
over. 


Initial 
velocity. 


Coefficient 

of 

gravity. 


Coefficient 

of 
resistance. 


Resistance. 


Mean velocity. 


In lbs. 
per ton. 


Total. 


Feet per 
second. 


Miles 
per hour. 


Post. 
to 10 

10 to 20 


seconds. 

64-50 
60-25 


feet. 

3300 
3300 


ft. per sec. 

48-00 
53-33 


•01098 
-01120 


•00767 
•00958 


17-18 
21 ^46 


349-8 

438-8 


51-16 
54-77 


34-88 
37-34 



Six Grand Junction Carriages = 30*45 tons. 



Ground of 
experi- 
ment. 


Time 
occu- 
pied. 


Space 

passed 

over. 


Initial 
velocity. 


Coefficient 

of 

gravity. 


Coefficient 

of 
resistance. 


Resistance. 


Mean velocity. 


In lbs. 
per ton. 


Total. 


Feet per 
second. 


Miles per 
hour. 


Post. 
OtolO 

10 to 20 


seconds. 

76-75 
67-00 


feet. 
3300 

3300 


ft. per sec. 

38-26 
46-32 


-01098 
•01120 


•00681 
•00825 


1525 

18^48 


464^4 
561-2 


43-00 
49-25 


29-31 
33-58 



We shall now examine the experiments made on the Grand Junction planes, 
and then present a summary of the results of the whole series. A moderate 
breeze blew directly down the plane during the course of the experiments. Its 
effects could not be accurately estimated, but as the wind acted to favour the 
descent of the train, the amount of resistance experienced and recorded must 
be less than could have been obtained in a calm state of the atmosphere. The 
error is on the right side for strengthening the force of the argument, which 
maintains the existence of an opposing power far exceeding what hitherto it 
had been supposed was encountered, and created as it were by the speed itself. 
At no very distant period in the history of railways, calculations were adduced 
before committeesof the Houses of Parliament, to prove the dangerous tendency 
of permitting such gradients as 1 in 100 to be formed on any railway, and to 
show what an enormous and fearful acceleration would take place in the mo- 
tion of a train if allowed to descend such planes without control. Even a 
plane of 1 in 177, it was supposed would demand a vigorous application of the 
brakes to limit the velocity within due bounds. In the infancy of the system, 
and the absence of extended experience, mistakes like these were natural. A 
valuation of the friction of carriages had been frequently made by various in- 
quirers with a considerable degree of accuracy. They however overlooked 
in a great measure the influences brought into play by the rapidity of motion, 
and erred in forming too early generalizations from data still imperfect, ap- 
plying the same standard to weigh the opposing forces, whether the train were 
proceeding at the speed of a steam-boat on the ocean, or winging its way 
through air with the swiftness of an eagle's flight. 

The experiments described in this and the former Report show the fallacy 
of erecting theories and establishing formulae on too slender a basis of facts. 
In a department of science, whose principles and laws are not yet fully deve- 
loped, it behoves us to proceed upon a plan of the most cautious and rigid 
induction. Formulae derived from mere theoretical considerations are of little 



ON RAILWAY CONSTANTS. 255 

value in reference to such a subject ; but they may answer a more useful pur- 
pose when applied to express in a condensed form results between which an 
analogy has been traced, serving thus as the first steps of a generalization to 
be completed only by multiplying observations in every possible way. 

On the 11th July, 1839, the eight second class Grand Junction carriages 
were taken to the planes, extending from Madeley to Crewe. The wind, as be- 
fore noticed, blew down the plane. The train of eight carriages was thrice 
discharged over the head of the plane, at a speed varying from 23 to 26 miles 
per hour. 

Secondly, one half the train, or four carriages, was dismissed over the head 
of the plane at 40'9 miles per hour ; the other half, or four carriages, was dis- 
missed at 32*73 miles per hour ; and, lastly, a train of six carriages was dis- 
missed at the speed of 25*57 miles per hour. 

1. Eight carriages, weighing gross 40*75 tons, dismissed over the top of 
Madeley plane, 1 in 177, at 23*71 miles per hour, accelerated to 24*79 miles 
per hour, and varied between 24*79 and 23*54 miles per hour, until reaching 
the foot. See Table, No. IX. 

2. Same train dismissed at 23*37 miles per hour, accelerated to 28*21, and 
varied between 28*21 and 25*77 miles per hour, until reaching the foot. See 
Table, No. X. 

3. Same train dismissed at 26*39 miles per hour, accelerated to 27*05 miles 
per hour, and varied between 27*05 and 25*17 miles per hour, until reaching 
the foot. See Table, No. XI. 

In the first case the maximum speed was attained at post No. 40 ; in the 
second case at post No. 48 ; in the third case at post No. 52. Let us com- 
pare the times of descent from post No. 40, for instance, to post No. at the 
foot of the plane, and deduce from thence the average uniform speed over that 
distance of 4000 yards. The times were respectively, 

5 min. 39*25 seconds = 24*1 miles per hour. 
5 . . . 8*25 ... = 26*4 
5 . . . 18*50 ... = 25*6 
The mean of the whole is 25*4 miles per hour. 

The circumstance of the speed having ceased to accelerate and having be- 
come uniform, renders unnecessaiy any calculation of the amount of resistance ; 
for it has been already shown that, in the case of uniform motion, the coefli- 
cient of gravity is equal to the coeflScient of resistance. The fraction j-fy in 
this instance then represents the coefficient of resistance ; in other words, 
12*65 lbs. per ton was the mean resistance encountered by the train of eight car- 
riages, tvhen moving at the mean velocity of25'4f iniles per hour. 

Upon reaching the foot of the 177 plane, the trains passed on to a plane of 
1 in 265, extending from the post numbered to that numbered 54. The ob- 
servations of its motion afford the means of ascertaining the resistance at a 
slower uniform velocity. 

1. Eight carriages entered upon the 1 in 265 plane at 24*06 miles per hour ; 
their motion was gradually retarded to 19*83 miles, over a space of about 3000 
yards, and finally became uniform over the remaining distance. 

2. Same carriages entered the plane at 25*76 miles per hour ; their motion 
was retarded to 20*20 miles, over a space of 3000 yards, and finally became 
uniform, or nearly so over the remaining distance. 

3. Same carriages entered the plane at 25*57 miles per hour ; their motion 
was retarded to 19*02, over a space of 3500 yards, and finally became nearly 

; uniform. 



256 REPORT — 1841. 

The times of passing from No. 30 to No. 54 posts, 2400 yards, were re- 
spectivelj^ 

4 min. 8'0 seconds = 19"7 miles per hour. 
4 . . . 5-75 ... = 19-9 ... 

4 . . . 20-50 ... = 18-9 
The mean of the whole is 1 9*5 miles per hour. 

The force of gravity on the plane being expressed by ^^j, 8*45 lbs. per ton 
was the mean resistance encountered by the train of eight carriages, when moving 
at the mean velocity ofl9'5 miles per /lour. 

The train afterwards passed on to a plane of 1 in 330, but suffered throughout 
a gradual retardation, showing that the resistance exceeded the gravitating 
force on this plane. Were it deemed necessary a computation could readily 
be made of the resistance at still slower speeds from the observed rate of re- 
tardation, but this has already been determined from the Sutton experiments, 
which, from the absence of any disturbing effects produced by wind, are more 
to be depended upon. 

The trains of four carriages next require our attention. The fact of so 
slight an acceleration as that from 23 to 25 miles per hour, having been pro- 
duced during the descent of a plane more than 5000 yards in length, was suf- 
ficiently remarkable, and demanded an accurate verification. It was deter- 
mined accordingly to make a sort of experimentum crucis, by dismissing the 
train from the head of the plane at a velocity considerably exceeding the 
maximum hitherto obtamed during any portion of the descent, and to note 
whether, instead of further acceleration, an actual retardation would not take 
place. The event turned out as had been anticipated. 

The four carriages were dismissed over the top at 40 miles per hour ; their 
speed diminished ; when half way down the plane it was reduced to 30 miles 
per hour ; and by the time they reached the foot it did not exceed 25"17 miles 
per hour. See Table, No. XII. 

The plane, it became evident, was too short to allow the train to acquire the 
uniform velocity due to the resistance, otherwise, in all probability, the speed 
would have been further lessened. 

The remaining four carriages, composing a train of equal weight with the 
former, were now dismissed at 32*73 miles per hour. They were retarded to 
22*72 miles per hour, and then continued uniform to the foot, over a space 
of 1600 yards. The time occupied in traversing the last 1600 yards was 2' 
23" = 22*8 miles per hour. 12*65 lbs. per ton was therefore the mean resist- 
ance encountered by this train of four carriages, when moving at the mean ve- 
locity of22-S miles per hour.' 

At the top of the 1 in 265 plane the speed of the first set of four carriages 
was 25*17 miles per hour. This continued to decrease for 3400 yards, after 
which the motion became uniform at 19*2 miles per hour, indicating a resist- 
ance of 8*45 lbs. per ton. 

The wind, which up to the time of the last experiment had blown in a di- 
rection to favour the motion of the trains down the plane, now veered round 
to the westward and fell on the sides of the carriages, tending to press the 
flanges of the wheel against the rails. This new source of resistance was soon 
rendered evident by the sluggish motion of the second train of four carriages 
in the latter part of its course (Table XIII.) ; also by that of a train of six 
carriages (Table XIV.), which afterwards descended ; and lastly, by repeating 
the experiments with the entire train of eight carriages (Table XV.). 

The Time Tables are given in the App. (see Tabs. XIII. XIV. XV.), but we 



ON RAILWAY CONSTANTS. 



257 



deem it unnecessary to draw therefrom any numerical deductions with refer- 
ence to the value of resistance. A comparison of the last trial of the train 
of eight carriages with the first three trials of the same train is well worthy 
of notice, as illustrating the powerful effects of a side wind. In the first case 
the mean initial velocity at the top was 24 miles per houi-, and the mean final 
velocity at the foot, 25"4 miles per hour. Under the influence of a side wind, 
the initial velocity being 20*07 miles per hour, the final velocity at the foot 
M'as only 17*69 miles per hour, with the probability of a further retardation 
had the incline been longer. 

The following Table presents a summary of the calculations we have made 
of the various amounts of resistance opposed to the different trains, on the lo- 
calities and under the circumstances assigned. 



Nature of the Traill. 


Weight 
of the 
Train. 


Name of incHned 

plane where 

experiment was 

made. 


Mean velocity. 


Measures of resistance. 




Coefficient 

of 
resistance. 


Pounds 
per 
ton. 


Total. 


Feet per 
second. 


Miles 
per hour. 


3L.& M. coaches... 
Ditto 


tons. 

14^80 
14-8 
148 
14-8 

20-45 
20-45 
20-45 
20-45 
20-45 

30-45 
30-45 
30-45 

40-45 
40-45 
40-45 
40-45 
40-45 
40-45 


Sutton 1 in 89 
Ditto 


8-80 
33-00 
38-37 
43-42 

8-80 
28-16 
33-44 
51-16 
54-77 

8-80 
43-00 
49-25 

8-80 
28-60 
30-13 
37-25 
37^93 
4342 


6-00 
22-50 
26-16 
29-60 

6-00 
19-20 
22-80 
34-88 
37-34 

6-00 
29-31 
33^58 

600 
19-50 
20-54 
25-40 
25-86 
29-61 


-00268 
-00367 
-00539 
-00726 

-00357 
■00377 
-00564 
•00767 
•00958 

•00357 
•00681 
•00825 

•00357 
•00377 
•00505 
•00564 
-00547 
-00654 


6-00 

8-22 

12-07 

16-26 

8-00 

8-45 

12-65 

17-18 

21-46 

8-00 
15-25 

18-48 

8-00 
8-45 
11-31 
12-65 
12-25 
14-65 


88-8 
121-6 
178-6 
240-7 

163-6 
172-8 

258-7 
349-8 
438-8 

243-6 
464-4 
561-2 

323-6 
341-8 
457-6 
511-7 
495-6 
592-6 


Ditto 


Ditto 


Ditto 


Ditto 


4 Gd. Jn. coaches... 
Ditto 


Sutton 


Madeley 

Ditto 


Ditto 


Ditto 


Sutton 


Ditto 


Ditto 


6 Gd. Jn. coaches... 
Ditto 


Sutton 


Ditto 


Ditto 


Ditto 


8 Gd. Jn. coaches... 
Ditto 


Sutton 


Madeley 

Sutton 


Ditto 


Ditto 


Madeley 

Sutton 


Ditto 


Ditto 


Ditto 







One of the important questions which the examination of such a series would 
suggest is, whether any relation can be traced between the speed and the ex- 
cess of resistance produced by the speed, and to what extent this excess is mo- 
dified by altering the size of the train. To enable the reader more readily to 
perceive what degree of connection subsists, the following table is constructed, 
presenting, in one column, the speed in miles per hour ; in anothei", the weight 
and description of the train ; and in a third, the excess of resistance in pounds 
per ton, or difference between' the total resistance and the resistance due to 
friction alone, the whole being arranged in the order of increasing speed, group- 
ing together experiments with trains of unequal sizes when their respective 
velocities were found nearly equal. 

The excess of resistance, as exhibited in the fourth column, evidently in- 
creases with the speed. Thus, at 20*54 miles, the excess is 3*31 lbs.; at 25-86 
miles, 4*25 lbs ; at 29*61 miles, 6*65 lbs. per ton, in a train of eight carriages. 



1841. 



258 



REPORT — 1841. 



Speed in miles, 
per hour. 


Train. 


Excess per ton 
of load. 


Number of 
Carriages. 


Weight. 


19-20 
19-50 
20-54 
22-50 
22-80 
26-16 
25-40 
25-86 
29-60 
29-31 
29-61 
34-88 
33-58 
37-34 


4 
8 
8 
3 
4 
3 
8 
8 
3 
6 
8 
4 
6 
4 


Tons. 

20-45 

40-45 

40-45 

14-8 

20-45 

14-8 

40-45 

40-45 

14-8 

30-45 

40-45 

20-45 

30-45 

20-45 


Pounds. 

0-45 

0-45 

3-31 

2-22 

4-65 

6-07 

4-65 

4-25 

10-26 

7-25 

6-65 

9-18 

10-48 

13-46 



In like manner, the excess at 29*3 1 miles per hour is 7*2.5lbs., and at 33"58 
miles, lO'^Slbs. per ton, in a train of six carriages. 

So in a train of four carriages, at 22*8 miles, the excess is 4*65 lbs.; at 34*88 
miles, 9'181bs.; and at 37'34 miles, 13*46 lbs. per ton. 

In a train of three carriages, at 22*5 miles, the excess is 2*22 lbs. ; at 26*16 
miles, 6*07 lbs.; and at 29*60 miles per hour, 10*26 lbs. per ton. 

The trains of four and eight carriages respectively, showed an excess of 
about half a pound only, but their motion was in some degree affected by 
the wind. 

The excess of resistance per unit of the load increases as the size of the 
train diminishes, though not in the same proportion. This consequence would 
naturally be expected from the circumstance of an equal frontage being ex- 
posed to the air, whether the train consist, for instance, of three or eight car- 
riages. Whatever resistance may be occasioned by the atmosphere acting on 
that frontage would in the one case be divided over three, and in the other 
over eight carriages. The fact of its not increasing in the same proportion 
pi'oves that the train is subject to a resistance independent both of friction 
and mere frontage, and that in fact many complicated causes conspire to pro- 
duce the entire resistance. 

At the speed of 29 to 30 miles per hour there is a group of experiments 
made with three, six and eight coaches, which seems best to exhibit the effect 
alluded to. The increase of the train from three to six coaches, diminishes 
the excess per ton about 3 lbs., and increases the total excess of resistance in 
the proportion of 1 to 1^, not as 1 : 2, which is the proportion of the loads. 

We do not, however, consider the observations to be as yet sufficiently nu- 
merous to warrant the foundation of any specific theory of resistance. The 
number of experiments in each group is extremely limited ; some of the cir- 
cumstances influencing the results, as for instance the wind, are not to be 
estimated, and therefore we deem it wiser to abstain from entering into the 
mathematical consideration of the laws which regulate the motion of solid 
bodies through a fluid medium until we can procure a mean from a large col- 
lection of groups of facts similar to those of which we have just afforded a 
specimen, otherwise we shall be in danger of having our inferences over- 
turned by succeeding experiments, and discredit thrown upon the character 
pf our inquiries. 



ON RAILWAY CONSTANTS. 



2.59 



The most important results are those relating to the train of eight car- 
riages, because this load is the nearest approach to the average size of the 
ordinary passenger trains usually travelling upon railways. Thirty miles per 
hour is a fair average speed ; and the resistance encountered by such a train 
moving at thirty miles per hour amounts, as we have already shown, to 
nearly 1 5 lbs. per ton, or almost double the value of friction only. These 
are results of an eminently practical tendency, indicating at what expenditure 
of power we can expect to be able to transfer a given load, and what degree 
of excess of power in the motive force, over and above the power required 
to overcome the fi'iction, is necessary to the maintenance of an assigned rate 
of speed. The friction may no doubt be made less than 8 lbs. per ton by 
proper attention to the accurate fitting and perfect lubrication of the axles, 
and to the squareness with which they are placed on the framing, as indeed 
is made evident by the fact of certain carriages having run with a friction of 
only 6 lbs. per ton ; but it is scarcely probable that a much lower amount 
will be attained, nor indeed would the reduction be of much importance in 
the economic working of passenger trains, which, from their high velocity, 
must necessarily bring into play large and independent soui-ces of resistance. 

Having ascertained the resistance to trains at various speeds, and under 
the circumstances in which they are found when employed in the regular 
traffic of the road, the attention of the Committee was earnestly directed to 
discovering how far any diiference in the external configuration of the train, 
and modification of the form of the front or hind surfaces, or any altera- 
tion in the shape of the leading vehicle, might affect the resistance it 
experienced. 

The information obtained in the course of this part of the inquiry is of a 
negative rather than a positive nature, proving that certain changes do not 
aflPect the resistance, but not satisfactorily pointing to any general principle 
whereby we can decide upon what the increase of resistance precisely 
depends. 

The form of the front and the hind end of a train of carriages is flat, pre- 
senting an area of 62 square feet, including a sectional transverse measure- 
ment of the area of the axle and wheels, and springs and axle-boxes. To 
give the train the power of more readily cutting its way through the atmo- 
sphere, a sort of boat-shaped appendage was provided. Two boards, equal 
in height to the body of the carriage, were united in front, at an angle, the 
vertex being 5 ft. 6 in. before the flat front, and the base 6 ft. 6 in., cor- 
responding with the width of the carriage. A single coach, weighing 5*37 
tons, was dismissed from post No. 0, at the top of Sutton Plane, first with the 
prow applied in front, and afterwards without the prow. 

The following Table is abstracted from Tables XVIII. and XIX. given 
in the Appendix : — 



One Carriage 
5-37 tons. 


Total Time 
distance run. ' occupied. 


Time of de- 
scending Sut- 
ton Incline, 
2420 yards. 


Maximum 
speed. 


Pointed front 

Flat front 


Yards. 

3975 
3905 


m s 
10 59 
10 59 


m s 
5 54 
5 5 


Miles. 
24-3 
23-7 




Diiferences 


70 





49 


0-6 



The diff'erence is only seventy yards in a distance of more than two miles ; 
the times of performing the distance precisely the same. 

s2 



260 



REPORT — 1841. 



A train of eiglit carriages, weighing gros.s 40'75 tons, was dismissed from 
the top of Madeley Plane,"both with the pointed front and the flat front ; see 
Tables IX. and X. ~ 



The following is an abstract :- 



Eight Carriages 
= 40-75 tons. 


Total 

distance 

run. 


Time 
occupied. 


Initial 
speed. 


Time of descending. 


Time of de- 
scending the 
three planes, 
13,500 yards. 


1 in 177. 


1 in 265. 


1 in 330. 


Pointed front ... 
Flat front 

Differences.... 


Yards. 
14411 
14331 


m s 

26 lU 
25 OJ 


Mile.s. 

23-7 
23-3 


8 4f 
7 14f 


8 50i 
8 32i 


4 50J 
4 56| 


21 45A 
20 41- 


80 


1 lOJ 


0-4 


50 


ISi 


6i 


1 1| 



The difference is only eighty yards in a distance of eight miles, and the 
other differences also far too small to establish any actual difference in the 
resistance. 

The pointed prow was next applied to a train of three carriages, weighing 
gross l-i'S tons. This train was dismissed four times down the Sutton Plane. 
In the first and last trips the train descended without having the prow 
attached either before or behind, and in its ordinary state. In the second 
trip the prow was fixed behi7id the last carriage ; in the third trip in front of 
the first carriage. The weather was perfectly fine and calm. The following 
results are abstracted from Tables I. II. III. IV. in the Appendix : — 



Three Carriages 
= 14-8 tons. 


Total 

distance 

run. 


Time 
occupied. 


Time of 
descending 

Sutton, 
2420 yards. 


Maximum 
speed. 


Time of 
nmning 
the first 
2i miles. 


Pointed front 

Flat front and end. 


Yards. 

5576 
5518 


m s 

13 1 
13 25 


m 8 

4 23 
4 22 


Miles. 

321 
321 


7 30 
7 32 


Differences 

Pointed end 

Flat front and end. 


58 

5350 
5209 


24 

13 45 
13 50 


1 

4 25 

4 28 


0-0 

31-0 
32-1 


2 

7 50 
7 54 


Differences 


141 


5 


3 


11 


' 



The differences are extremely slight, and such only as would have taken 
place with the same experiment repeated twice over. The pointed prow was 
placed at the back of the train, to test an opinion expressed by several indi- 
viduals who were interested in the inquiry, that the resistance would in some 
measure be found to depend upon the shape of the hind surface of the last 
vehicle, and that if the end were pointed, the air would quickly and gently 
slide into the space just before occupied by the train, without causing so great 
a relative vacuum. The experiment showed that the pointed prow, whether 
placed behind the last carriage, or before the first carriage, exercised no 
appreciable influence on the rate of the train's motion, or on the resistance 
of which that motion was the index. 

The next subject of inquiry was, whether the circumstance of the car- 
riages being sent with their square ends foremost, instead of being preceded, 
as they usually are, by the engine and tender, Avas likely to throw any doubt 
upon the correctness of the values of resistance determined heretofore for 
the several trains of carriages. 



tA 



ON RAILWAY CONSTANTS. 



261 



The engine, it might be supposed, would act as a sort of cut-air to throw 
aside the current, and break its force before it reached the flat surface of the 
carriage. However improbable such a consequence might be after the indi- 
cations just recorded, where a still more decided change of form was made 
the subject of trial, it was nevertheless determined to put the case to actual 
experiment. Accordingly a four-wheeled engine, the "Fury" and its tender, 
were weighted equal to two carriages. The pistons, connecting rods, and 
other working gear of the engine, were detached from the driving wheels, so 
that the engine should be subject to no other friction save that to which a 
carriage is subject. The grate-bars, ash-pan, &c. were removed, in order to 
make the engine as light as possible, and to assimilate its weight to that of a 
loaded carriage; two carriages were also prepared of equal weight. The 
Fury and tender were first dismissed down the Sutton Incline ; afterwards 
the two carriages, and their times of descent compared. 

The following is an abstract of the performances recorded in Tables 
XX. XXI. :— 



Train. 


Weight. 


Total 

distance 

run. 


Time 
occupied. 


Time of 

descending 

Sutton Incline, 

2420 yards. 


Maximum 
speed. 


Furv and tender 


Tons. 
11-38 
11-33 


Yards. 

4710 
4577 


m s 

11 37 
11 40 


m s 
4 45 
4 40 


Miles. 

29-0 
28-1 






Differences 


•05 


133 


3 


5 


0-9 





The differences, as will be seen, are extremely slight. Each train was now 
increased by four carriages, and the contest took place between a train con- 
sisting of the Fury tender and four carriages, and a train of equal weight, 
consisting of six carriages. Tables XXII. and XXIII. may be referred to. 
The following is an abstract : — 



Train. 


Weight. 


Total 

distance 

run. 


Time 
occupied. 


Time of 

descending 

Sutton Incline, 

2420 yards. 


Maximum 
speed. 


Fury, tender and 4 coaches... 
Six coaches 


Tons. 
27-45 
27-45 


Yards. 
5068 
4850 


m s 
12 9 
10 48 


m s 

4 49 
4 43 


Miles. 

30-5 
31-0 




Differences 




218 


1 21 


6 


0-.) 





Here again there are no greater differences than might be expected with 
an experiment repeated twice over with the same train, and we may fairly 
conclude that the form of the front has no observable effect, and that whether 
the engine and tender be in front, or two carriages of equal weight, the resist- 
ance will be the same. 

It has already been shown that at equal speeds, tlie excess of resistance, 
after deducting the friction, does not increase in the ratio of the load; a 
train of six carriages, at twenty-nine and a half miles, having experienced 
only one and a half times the. resistance that a train of half that size at the 
same speed was subject to. This fact pointed to the conclusion that the 
excess of resistance observed at high speeds was due to something besides 
the mere extent of frontage, and this conclusion was confirmed by the ex- 
periment we are about to cite.