CONTENTS OF VOL. XXI.—FOURTH SERIES. 
M. G. Wertheim on the Cubical Compressibility of certain 
sold tromorenedus Bodies: oo... ris tici. bis eetewens ci 
Mr. T. Tate on a New Electrometer (the Siphon Electrometer) 
for measuring the Electrical Charge of the Prime Conductor 
of a Machine; and on the Dispersion of different Liquids by 
Migew@i@al Action [5 i.) ci cise fnew iid ae po eka 
“gece of the Royal Society :— 
Dr. Hofman on the Action of Nitrous Acid upon Nitro- 
Preuylenediamine:.), .... +. veal ei Ieidaa i dawyias 
Mr. W. Hopkins on the Construction of a new Calorimeter 
_ for determining the Radiating Powers of Surfaces .... 
Mr. C. G. Williams on Isoprene and Caoutchine ...... 
Dr. Joule and Prof. W. Thomson on the Thermal Effects 
me Pinas in Motion. . ...< . --.-.22 Rt Ue Pe EES ey eee 
Mr. E. J. Lowe on a new Ozone-box and Test-slips .. .. 
Proceedings of the Cambridge Philosophical Society :— 
The Rev. Dr. Donaldson on the Origin and proper value 
geene word. © Armument 1.5 deh wigs tse a.com eo chs ose 
Prof. Challis on the Planet within the orbit of Mercury.. 
Prof. De Morgan on the Syllogism, No. IV., and on the 
Bozic of Relations. .isavc as .aegedtt Weed oes 
The Public Orator on the Pronunciation of the Ancient 
and Modern Greek Languages .. 
Mr. H. D. Macleod on the present State of the Science ‘of 
2S LT ew bn 5061057 1h ee a a eT an lei See RD nEnT 
On the Optical Properties of the Picrate of Manganese, by M. 
ELE? LYSE 8 OIE Se ae ae ee er Pe 
Experiments on the possibility of a Capillary Infiltration through 
Porous Substances, notwithstanding a strong counterpres- 
sure of vapour, by M. Daubrée 
PS eS. OLW 6 Ss 608.6: e) 0) ie! 6: 0) 6 8 ee 0.8) 6)» 
NUMBER CXLIII.—SUPPLEMENT TO VOL. XXI. 
M. L. Lorenz on the Reflexion of Light at the Boundary of two 
eomec Uransparent Media: . 22.05. 2.4. ia ee ele 3 hig ore'e's 
Mr, A. Cayley on a Surface of the Fourth Order .......... 
Dr. Atkinson’s Chemical Notices from Foreign Journals 
rae @uallis on Theoretical Physics... 60.0605... 66 cece ws 
Mr. D. Vaughan on Phenomena which may be traced to the 
Presence of a Medium pervading all Space .............. 
Prof. Sylvester on a Problem in Tactic which serves to disclose 
the existence of a Four-valued Function of three sets of three 
PPeES CACO VY OE a ee RIGS SRW ES ERMA RET SPER EL 
Notices respecting New Books :—Mr. Todhunter’s History of 
the Progress of the Calculus of Variations during the Nine- 
Rene MCONUUEY: 53 8 ood oicisi oS vs Beda de wind os,i sipaits 
Proceedings of the Royal Society :— 
Messrs. J. B. Lawes, J. H. Gilbert, and Dr. Pugh on the 
Sources of the Nitrogen of Vegetation.............. 
Mr. F. J. Evans on the Deviations of the Compass observed 
on Board of all the Iron-built Ships and a selection of 
the Wood-built Steam-ships in Her Majesty’s Navy, &c. 
Vii 
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