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 silicic 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 pro- 
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- 
other are arranged according to their molecular type. 
“« 2d. The compounds of the members of any other group than group 
first, with the members of group first, are arranged together in groups 
according to molecular types principally, and according to isomorphism 
wherever isomorphisms exist.’”* 
Although we have presented 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 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 : fj 
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 Rey. 
Peter B. Broprs, 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. Nicotzer while 
in employ under the Bureau of the corps of topographical engineers. 
Washington, 1843. (With a large map.) 
lil. The Encyclopedia of Chemistry, theoretical and practical ; pre- 
senting a complete and extended view of the present state of chemical 
science. Part IX, ending with cobalt. pp. 464. 
IV. North American Sylva: Micwavx and Nurratt. Vol. IV, 2d 
half, royal 8vo. pp. 57 to 1386. 23 plates. 
* Mr. Gibbs acknowledged his indebtedness to Drs. Kane and Graham, for the 
aid he has derived from their published suggestions on this subject. 
