Page:Proceedings of the Royal Society of London Vol 1.djvu/264

Rh 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 maybe 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 follows; 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.

The instruments with which Mr. Gilpin‘s observations on the variation, 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 Philosophical 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 pursued to ascertain what allowances were proper to be made in the results of his observations.

After stating the circumstances above mentioned, Mr. Gilpin proceeds 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.