^{page 189 note *} Lambert, Pyrometrie, 4to, 1779, page 356.

^{page 190 note *} Supplement to the 6th edition of the Encyclopedia Britannica, article Climate, incorporated in the 7th edition.

^{page 194 note *} Philosophical Transactions, 1836, p. 577.

^{page 194 note †} More lately Mr Adie has constructed two sets of thermometers resembling these, one, extending to 24 French feet for Greenwich Observatory; the other, including only the 12 feet thermometer, for Mr Caldecott of Trevandrum in India. Both of these sets of instruments were fortunately transported to their destinations without any accident. The graduation of the Greenwich instruments was performed by myself, and a much larger number of points fixed than above described. The result was examined, and the scale determined, by a simple method of graphical projection and interpolation, which led to the most satisfactory results; I should, therefore, recommend this method to others undertaking the same tedious and difficult operation.

^{page 195 note *} Encyc. Brit., Article Climate.

^{page 195 note †} Subsequently (May 1838), a quantity of Roman cement was employed to secure completely the opening of the holes.

^{page 200 note *} The application of this correction becomes exceedingly easy, by considering the correction for air temperature to apply, not only to the exposed part of the tube, but also to the first 9 inches of the buried stem.

^{page 202 note *} Fechner's Repertorium, II. 430. The expansion of absolute alcohol is somewhat greater as given by Muncke, in a paper in the Petersburg Transactions, read 5th September 1834.

^{page 204 note *} Quetelet, Annales de l'Observatoire Royale de Bruxelles, iv. 150.

^{page 208 note *} For farther particulars, see the Appendix at the end of this memoir, and also Sub-Section F.

^{page 212 note *} See the Appendix.

^{page 214 note *} Pyrometrie, § 675.

^{page 214 note †} Ann. de l'Observatoire de Bruxelles, iv. 169.

^{page 217 note *} Annales, &c., vol. iv. p. 112.

^{page 218 note *} Poisson, Théorie de la Chaleur; Suppl., p. 4.

^{page 218 note †} Mean of two experiments, 1·556 and 1·538. It is evident, that since it is required to find the specific heat of unit of volume of the mass to be heated or cooled, we must take the aggregate of sand as we find it in the soil, and not the specific gravity of the individual grains. Accordingly, the specific gravity was determined by comparing the weights of closely packed sand and of distilled water contained in a stoppered phial.

^{page 220 note *} See Second Report on Meteorology, Arts. 104, &c, in the British Association Reports for 1840.

^{page 220 note †} Taken from the Second Report on Meteorology, British Association Report, 1840, Art. 88, &c.