J. L. Smith on determining the Alkalies in Minerals. 89 
A more speedy method of separating the Alkalies directly from the 
lime fusion for both qualitative and quantitative determination. 
53, As soon as the fusion with carbonate of lime and sal-ammo- 
niac, gave evidence of the mineral being so thoroughly attacked, 
the question naturally arose as to the condition the alkalies were 
in after the fusion, and the possibility of dissolving them out by 
the agency of water alone, at least for the purpose of qualitative 
determination. Experiments directed to this object soon made it 
evident that the alkalies might be obtained from any silicate, 
without resorting to the use of acid as a solvent for the fusion. 
e mass as it comes from the crucible, is placed in a cap- 
sule with water, and then heated in a sand-bath or over a lamp 
for two or three hours, renewing the water from time to time as 
it evaporates. The mass disintegrates very shortly after being 
placed in the water. The contents of the capsule are next thrown 
ona filter, and the water passes through containing the chlorid 
of the alkalies, a little chlorid of calcium and caustic lime, all 
else that the mineral may have contained remains on the filter, 
except baryta and strontia if they be present in the mineral, but 
as these oxyds are of rare occurrence in silicates, no allusion will 
be had to them here. 
55. 'To the filtrate add carbonate of ammonia and boil for some 
time, when all the lime will be precipitated as carbonate, add a 
ew drops of a solution of carbonate of ammonia to the hot solu- 
tion to be sure that all the lime is precipitated, should this be the 
case, filter—the filtrate will contain the chlorids of the alkalies 
and chlorid of ammonium; it is evaporated to dryness over a 
water-bath in a small platinum capsule ; the capsule is carefully 
heated to expel the sal-ammoniac, and finally warmed up to 7 or 
00° F., it is then weighted with its contents, and the chlorids if 
mixed, separated in the way mentioned (45 and 46). The 
amount of sal-ammoniac to be expelled is quite small, not equal- 
ling the weight of mineral originally employed. 
56. Nothing in analysis can be simpler or more speedy than 
this process. Its constant accuracy still lacked some little to ren- 
der it perfect, as usually an amount of alkali remains behind, 
Tepresented by from 2, to one per cent. of the mineral used, cer- 
tainly a small amount, but still too much to be omitted in an 
accurate analysis. This also must be arrived at, and it can be 
accomplished in the following manner. 
57. hfier the fused mass fist been treated with watér filtered 
and washed as in (54), the filter and its contents are dried, the 
latter are detached from the filter, and rubbed up in a glaze 
Mortar with an amount of sal-ammoniac equal to one-half the 
weight of the mineral, and reheated in a platinum crucible ogi 
as in the first instance, treated with water, thrown on a filter and | 
Washed, the filtrate added to that from the first fusion, the whole 
treated with carbonate of ammonia, and completed as in (55). 
