Analyses of Books. 
145 
to our knowledge of the animal kingdom, to allow us to follow Horace’s maxim in 
this instance, and keep our descriptions under review and correction “ in nonum 
annum.” 
5. Geology of the Himmalaya. 
A correspondent wishes to have some further account of the Slate clays and Lime- 
stones described by Dr. Go van, in his communication to the Asiatic Society. He 
is said by the newspapers to have stated that gypsum is found in the former, there- 
by assimilating them with the Newer red sandstone ; and bivalve shells in the latter. 
Our correspondent wishes to know of what genera these shells are. He would also 
be thankful for a description of the two rocks, and a fuller account of their relations . 
6. Geology of Udayapur. 
Dr. Hardie, whose communications on the Geology of Central India, have been 
so often noticed in the Report of proceedings of the Asiatic Society, is employed we 
understand on a continuation of his paper on the Geology of the valley of Udayapur. 
He is in particular preparing very complete sections of the strata. We wait with in- 
terest the result of his labours. 
Analyses op Books. 
Transactions of the Royal Society of London. 
Part 1. 
For the year 1828, 
The first part of the Transactions of the Royal Society have reached this country; 
and, having been favoured with a sight of them, we hasten to lay before our readers 
a pretty full abstract of their contents. The papers appear to us to be all commu- 
nications of great interest, and fully support the high character that attaches to the 
Transactions of this learned body. 
I. Experiments to ascertain the ratio of the Magnetic forces , acting on a needle 
suspended horizontally in Paris and in London. By Captain Edward Sabine of 
the Hey at Artillery , Sec. R. S. pp. I t° 14- 
In making experiments on the intensity of Terrestrial Magnetism, at different 
places on the eartii's surface ; the principal precautions necessary are, to take care, 
that the power of the needle to be affected by the magnetic influence residing in 
tbe earth, does not alter, in the intervals of the several experiments ; and rhat the 
temperatures in which the experiments are performed, lie as nearly as possible, the 
Si *me. Both these objects were attorned in the present series; as the same needles 
"ere employed, at Paris, and London : and on returning to London, the experi- 
ments were again repeated, and found to give the same results. The like prurau- 
turns were taken, in determining the magnetic influences at London, and Edin- 
burgh.— With regard to the temperature, it was endeavoured, as far as was possible, 
Jo perform the experiments in the same temperature, at each place ; and to show 
"O'" far this effort was successful, the following table of the mean temperatures of 
the experiments compared, is given. 
- " at Paris 
at London 54°, 5 
50 
40.5 
54.5 
55 
54,5 
62 ° 
52 
59 
66,5 
54 
53 
As there is still a preponderance of temperature at Paris, the results were cor. 
'“H by using a formula of Professor Hansteeu’s. Supposing the time of a 
^rations in the temperature of / to be T seconds and in the temperature t to be 
1 spfflmds then T=T (1 0 000165 (t — t) the temperature being expressed m 
°T Fahrenheit. . . , . , . , . ■ 
„ T , he object was, to determine at each place, the time m winch the horizontal 
"^e performed a certain number of vibrations (100). The following extracts 
''■ gwe an idea of the instruments used, and the methods of proceeding 
The magnetic needle emploved in these experiments were cylinders of 0,16 inch 
"meter, ami 2,4 inches in length, pointed at the ends : they were suspended by a 
S11 ‘i?le silk fibre, of rather more than 5 inches in length, file box in which they 
!^ e , enclosed (as a protection from the weather) was of wood, having at 
ne bottom, a graduated circle in ivory ; rather exceeding in diameter ttie ien & ui 
