Observations on Shooting Apparatus. 
379 
1830.] -coo, 0 -i-j- - 
after calcination, the composition, according to this analysis, will be found, by in- 
creasing all the results 6 per cent, which will give as follows 
Alumina, 74,2 > 
Water, 
Oxyde of copper, 5,5 
99.4 
This composition does not differ much from the result of Professor John’s analy- 
sis dedSn being made in his of the oxyde of iron : the oxydes of copper and 
iron, 1 have already argued to be variable in quantity, and bestowing as variable a 
C °The precious* variety of turquoise may, however, be safely regarded as a sub-hy - 
dratc green variety was analyzed in a similar manner to the preceding, 
the composition appeared to lie as follows : — 
Alumina, (with trace of sulphuric acid,) 
Water, 
P rot oxyde of iron, 
Protoxyde of copper, 
100 
F Two <r rains of the white earthy turquoise, analyzed in the same way although 
i "rairined bv which operation it lost 19 per cent, of water, left a residue 
KYwVm? M nt. insoluble in nitric acid, which was, probably, silex or s.l.cate of 
i * • r n, P carbonate of ammonia also precipitated only 30 percent, of alumina 
Z n ric loZL llxhe copper was small in quantity, and no iron was 
from the nitric soiu ,{ifi r iencv of 20 per cent, therefore, remained 
recognized by desi ’ re preserving the reft of the specimen, prevented 
unaccounted fj ? . further than to ascertain that there was barely a perceptible 
my pursuing the inquiry luruier ^ ^ ig> of the three , the least soluble ; 
quantity of sulpln l P cxpect ed from its friable decomposed state. It is, 
contrary to what would 1 b J for this is more likely to be the nascent 
perhaps, improper to call ■ j » felspar, bv the action of the 
L™ of the the hydrate 
„7a?oo,rL a ;“r«ic" la’r, in tt cLnlar cayitie/or air bubbles of the iron stone. 
62 
18 
18 
2 
IV 
r nervations on Shooting Apparatus ; with directions by which 
.—Observatio g^ J ^ ^ /jwfe expense or trouble, 
Zahe a new sort of Charges or Cartridges, on a safe and simple prin- 
ciple. By Mr. J. Jenour. 
[From the Mechanics Magazine.] 
i i i,„ Pn written and the most contradictory notions have pre- 
Though much has been nnn »« rs reducible to a few simple facts, 
railed on the present subject, it appe. d f t0 himself and others. 
The sportsman’s principal f loading/and the utmost possible 
o/ any single heat of gain. 
effect of bis gun; that is to J, ^ ( between the nearest and the 
f without being liable o mang » . (admitting the gun to be of the best 
greatest distance practicable In ttajvww £ appear to be-1. 
materials and workmanship), the * 3 . Length of barrel. 4. Size 
Size of the bore. 2. Deviation fro 5 c ^ addi 6 . Leading and foulness of 
jf shot and proportions o 1 > Either with loose shot or cartridges of different 
barrel. 7. Clubbing °r ^Umg, eitb diffcrcnt wayg of loading, &c. , 
sorts. 8. The spread or dish of the s , y u bore ' boot sharper, or, in other 
First, as to the size ot the bore. G calibre> propor tionably ; thus, 
words, throw their shot strong ; , ifference Q f a 16-gauge light gun, with an ounce 
we may take as a maximum, bore about the size of a half-crown 
and half of No. 6 shot ; and a duck ojir case> the light gun would perforin 
piece, carrying a pound of -No. 1 b 
