244 



deposited, and by remaining there some time, is more easily digested 

 when it passes to the second, or digesting portion. 



The difference, with respect to the teeth, between those animals 



which ruminate, and those which (although they eat nearly the same 



kind of food,) do not ruminate, is, according to our author, as follows. 



Ruminants that are furnished with horns have molares, or grinding- 



teeth, in both jaws, and incisors only in the lower jaw. 



Ruminants that are without horns have, besides the above, what 

 may be called tusks, or fighting teeth ; but these are of no use in 

 eating. The Camelopardalis forms an intermediate link between the 

 two, as it has short horns and no tusks. 



Annexed to Mr. Home's paper, is an account of some experiments 

 made on the urine of the Camel, by Mr. Brande. 



The result of his experiments gives the component parts as fol- 

 lows ; but it must be observed, that the quantity he had to operate 

 upon was so small, that his analysis must be considered merely as 

 an approximation to the truth. 



Water 75 



Phosphate of lime, muriate of ammonia, sulphate of") g 



potash, urate of potash J 



Muriate of potash 8 



Urea 6 



95 



Observations on the Variation, and on the Dip of the magnetic Needle, 

 made at the Apartments of the Royal Society, between the Years 

 1786 and 1805 inclusive. By Mr. George Gilpin. Communicated 

 by Henry Cavendish, Esq. F.R.S. Read June 19, 1806. {Phil. 

 Trans. 1806,^. 385.] 



The instruments with which Mr. Gilpin's observations on the va- 

 riation, and on the dip of the magnetic needle were made, are the 

 same as were used in former observations, and are described by 

 Mr. Cavendish, in a paper printed in the 66th volume of the Philo- 

 sophical Transactions. But as the observations now communicated 

 by Mr. Gilpin are the first that have been given since the compass 

 was put up in the Society's Apartments in Somerset Place, he has 

 thought proper to describe very particularly its situation in the house, 

 at the time the observations were made, and also the method he pur- 

 sued to ascertain what allowances were proper to be made in the re- 

 sults of his observations. 



After stating the circumstances above mentioned, Mr. Gilpin pro- 

 ceeds to the observations. These are detailed in five tables, of which 

 the following is a summary account. 



Table 1. contains, in sixteen pages, the observations made on the 

 variation, at various but stated times of the day, from September 1, 

 1786, to December 31, 1787. It is so disposed, that the increase or 

 decrease of the variation may be seen by mere inspection. 



