386 Bibliography. 
The eleventh comprises potassium, sodium and lithium. 
The twelfth consists of yttrium and thorium. 
The thirteenth of cerium, latanium, didymium, erbium and terbium, 
The fourteenth comprises carbon, boron and silicon. The author 
proposes to reduce the received equivalent of boron and silicon by one 
third, and thus assimilate their acids in constitution to carbonic acid; thus 
CO,, BO,, and SiO,, and certainly, the general analogy of boracic 
and silicie acids, to the carbonic, in their chemical relations, and the 
great simplification which it would introduce in our views of the com- 
position of the natural silicates, appear to offer some ground for the ne 
posed change. 
The arrangement of the compounds is one obviously growing out of 
the system adopted for the elements, and we will only mention the prin- 
ciples of his classification. 
** Ist. The compounds of the members of group first with one an- 
einer are arranged according to their molecular type. 
e compounds of the members of any other group than group 
he with the members of group first, are arranged together in groups 
according to molecular ho yi and according to isomorphism 
wherever isomorphisms ex 
Although we have seen but an imperfect outline of Mr. Gibbs’s 
principles of arrangement, we may safely say that he has ably shown the 
gradation by which the different substances are united to each other, and 
fully vindicated the motto of his essay, “‘ Natura non a facit saltum.” 
8. New Books Received. —Among numerous, interesting, and im- 
portant works on our table, we have space in this number to note the 
titles only of the following : 
I. A History of Fossil Insects in the Secondary Rocks of England, 
accompanied by a particular account of the strata in which they occur, 
and of the circumstances connected with their preservation. By Rev. 
Peter B. Broviz, M. A., F. G.S.  8vo., pp. 130, plates 11. London, 
J. Van Voorst. 1845. 
II. Report intended to illustrate a map of the hydrographical basin of 
the upper Mississippi River, made by (the late). J. N. Niconzer while 
in employ under the Bureau of the corps of topographical vin 
Washington, 1843, (With a large map.) 
Ill. The Encyclopedia of Chemistry, theoretical and practical ; pre: 
senting a complete and extended view of the present state of ut 
science. Part IX, ending with cobalt. pp. 464. 
IV. North American Sylva: Micuavx and Nurratu. Vol. IV, 2d 
half, royal 8vo. pp. 57 to 136. 23 plates. pe LO = 
* Mr. Gibbs acknowledged his indebtedness to Drs. Kane and Graham, for the 
aid he has derived from their published suggestions on this subject. 
