pag: 
Observations on Mr Sang’s Remarks relative to the Great 
Logarithmic Table compiled at the Bureau du Cadastre 
under the direction of M. Prony. By M. F. Lefort. r 
Communicated by Mr Sang, who has translated the 
paper from the French, . . . . 563 
Observations relatives aux remarques publiees par M. 
Edward Sang dans les u Proceedings of the Royal 
Society of Edinburgh, Session 1874-1875,” sut les 
grandes tables logarithmiques et trigonometriques cal- 
culees au Bureau du Cadastre sous la direction de Prony; 
par F. Lefort, Inspecteur general des Ponts et Chaussees, 
membre correspondant de l’Academie des Sciences de 
Naples, . . . . . . 564 
Observation relative to Mr Edward Sang’s u Remarks on 
the Great Logarithmic and Trigonometrical Tables 
calculated in the Bureau du Cadastre under the direction 
of Prony,” published in the Proceedings of the Royal 
Society of Edinburgh, Session 1874-1875, by M. F. 
Lefort, Inspecteur General des Ponts et Chaussees, 
Corresponding Member of the Academy of Sciences of 
Naples, ...... 574 
Reply to M. Lefort’s Observations. By Edward Sang, . 581 
Monday , 2 ls£ June 1875. 
Note on Electric Resistance of Solutions, By William 
Durham and P. R. Scott Lang, M.A.,. . . 587 
On the Circumscribed, Inscribed, and Escribed Circles of a 
Spherical Triangle. By C. G. Colson, Esq. Com- 
municated by Professor Tait, . . . . 589 
On some Remarkable Changes, Additions, and Omissions of 
Letters in Certain Cognate European Words. By the 
Hon. Lord Neaves, , . . . . 596 - 
De Interpolation des fonctions irrationnelles en general, et 
des fonctions logarithmiques en particulier, a l’aide des 
tables numeriques. Par F. Lefort, inspecteur general 
des Ponts et chaussees, membre correspondant de 
FAcad^mie des Sciences de Naples, . . . 602 
Monday , 5th July 1875. 
The Theory of the Causes by which Storms Progress in an 
Easterly Direction over the British Isles, and why the 
Barometer does not always indicate real vertical pres- 
sure. By Robert Tennent, Esq., . . . 612 
On Electric Images. By Professor Tait, . . . 623 
Laboratory Notes. By Professor Tait — 
a. On the Origin of Atmospheric Electricity, . .623 
h. Experiments on the Thermal Conductivity of some 
Dielectrics. By Messrs C. M. Smith and C. G. 
Knott, . . . . . . 623 
A Chapter on the Tides. By the Rev. James Pearson, M.A., 
Vicar of Fleetwood. Communicated by Professor Tait, 627 
Farther Researches in very perfect Yacua. By Professors 
Dewar and Tait, ..... 628 
On the Electric Resistance of Iron at a High Temperature. 
By Messrs C. M. Smith, C. G. Knott, and A. Mac- 
farlane. (Plate), , . ( . yTY . . 629 
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