Dec. 9, 1869] 
fact, are the most frequently recurrent and concurrent 
planes of a crystal. The far greater elegance of the stereo- 
graphic projection for the representation of the zones of a 
crystal than the sort of contracted and symbolised Quen- 
stedtian method employed by Professor Dana will certainly 
prevent this latter from ever becoming adopted in other 
works. Passing from the crystallographic to the chemical 
notation, we may say that Professor Dana accepts a sort 
of nuclear theory of chemical combination, and illustrates 
this by a corresponding notation. As, however, the use 
of this system is only partially introduced into the work, 
NATURE 
163 
we may dismiss it with the remark that, inasmuch as the 
use of formule of one shape or another to express a 
particular compound can only be a relative and not an 
absolute expression of the modes in which its elementary 
units are combined, when one such formula or system 
of formulating is to be conventionally selected for adop- 
tion, that will be the best to select which expresses best the 
| relations between the compounds from the point of view 
| of the author employing them. Professor Dana’s does not 
seem to us to meet this requirement as from the point of 
view of the mineralogist, N. STORY MASKELYNE, 
BELL’S NEW TRACKS IN NORTH AMERICA 
New Tracks in North America: A Journal of Travel 
and Adventure in 1867-68. By W. A. Bell, M.B., 
F,R.G.S., &c. With a map, 20 lithographs, 22 wood- 
cuts, and 3 botanical plates. 2 vols., 236 and pp. 
(Chapman & Hall.) 
HIS is an unusually important book of travels, giving 
222 
322 
not that it is a basin with a mm all round to act as an in- 
surmountable barrier to drainage, but rather because it is 
in reality a collection of hundreds of smaller basins, each 
of which has its stream and lake, which lose by evaporation 
and percolation what is supplied by the limited rainfall. 
Cultivation is, however, increasing the rainfall in Utah, 
and the Great Salt Lake has consequently of late years 
been steadily rising. The rainfall from year to year is 
interesting particulars of the vast wild Western ! irregular, At Fort Yuma, on the borders of California 
country which, and Arizona, it 
though still the was in four re- 
home of the Pai ees Above cent years 0°33, 
Apache and the 4 . oe S57 04s200nand 
Buffalo, is every U) per Carboniferous limestone, 2°94 inches. Irri- 
day being more _ 5,500 ft. : r 6,800 ft. gation must be 
and more #4277 resorted to for 
brought into sub- Crass-stratified sandstone. all agricultural 
jection by the operations. 
settlers, traders, 4 300 it, EG aap 5,600 ft. The _ barren, 
miners, capital- a monotonous 
ists, and railways mountain ranges 
of the “ Anglo- ofthe great basin 
Saxons” of Ame- are rich in mine- 
rica, as Dr. Bell ae rals. One silver 
calls them. 3,300 ft. 46001. Jode, the Com- 
The author stock, yields an- 
was well placed a = = nually four mil- 
for sbeathibe re- oer lions sterling, or 
liable informa- Devonian? SSeS more than all the 
tion, having been minesin Mexico, 
attached in 1867 ‘Limestone, mud-rocks, Jo and Nevada fur- 
to the surveying and sandstones. — nished twenty 
expeditions of Silurian. —— million dollars 
the Pacific Rail- 1,000 ft. Potsdam sandstone. 2,300 ft. oof gold in 1867 
way as_ photo- to California’s 
grapherand phy- twenty-five. 
sician. In this Copper and iron 
manner he tra- are also plenti- 
velled “about Taare ful, and the un- 
5,000 miles be- 
worked coal- 
yond the pale of Ba Sy ae aa reg pee AN fields are nume- 
Sage . nn < fe eas ee md z ov g = 
civilisation and SAA ARS a EN toni a SPEER Ma? Boe rous. Hydraulic 
railways.” His Fe TS power isnowem- 
contributions to SECTION OF THE CANON OF THE COLORADO ON THE HIGH MESA, WEST OF THE ployed in mining 
a LITTLE COLORADO (BY J. S. NEWBERRY, M.D.) a : & 
the physical geo- in California. 
graphy of the as- The machine 
tonishing country south-west of the Rocky range are care- 
fully done. He writes a brief treatise on the natural drain- 
age system of the district, and especially of the Great Basin, 
which is considerably larger than France, and so-called be- 
cause none of its rivers reach the sea. The reason of this is 
| used was invented in 1852 by one Mattison, of Connecticut, 
and directs a stream of water from a two-inch pipe undera 
pressure of perhaps 200 ft. perpendicular, which gives a 
tremendous force, against a bank or hill-side, containing 
placer gold, tearing down the earth into the washing sluices 
