CHEMICAL NOTATION IN THE PHARMACOPffilA. 
219 
tricalcic, and triferrous salts. The “ arseniate of soda” of the Pharmacopoeia 
appears to be the disodic arseniate; but, as its composition may be deter¬ 
mined by the volumetric test, the formula is not required. The name 
“ borax” indicates a well-known commercial product, and the formula at¬ 
tached to it could safely be omitted. If necessary, the officinal compound 
might be distinguished from octahedral borax by the statement that it is or¬ 
dinary or prismatic borax, containing 47T2 per cent, of water, which is given 
off at a red heat. The formulsB of the basic salts do not appear to throw any 
useful light upon the constitution of these bodies. The compound called 
“ white bismuth ” certainly contains the elements of water, and may be re¬ 
garded as a hydrato-nitrate, but hydrogen is omitted in the Pharmacopoeia 
formula. The composition of this basic nitrate of bismuth appears to vary 
according to the quantity of water used and the length of time spent in the 
washing. Again, the formula given for the so-called “ subacetate of copper,” 
or verdigris, implies that an extremely variable product has a fixed composi¬ 
tion. The composition of the so-called “subacetate of lead” is intimated 
by the quantitative oxalic acid test. The ofiicinal “ carbonates ” of magnesia, 
zinc, and lead are hydrocarbonates, or basic salts; and if their formulae were 
omitted, it would be advisable to give percentage representations of their 
composition. Thus, taking the present formula! as correct expressions, the 
“carbonate of magnesia” contains 41’88 parts of magnesia, 34‘56 of anhy¬ 
drous carbonic acid or carbonic anhydride, and 23 56 of water; the “ carbon¬ 
ate of zinc” contains 71'26 parts of oxide of zinc, 12'90 of carbonic anhydride, 
and 15’84 of water; and the “carbonate of lead ” contains 86'32 parts of 
normal oxide of lead, 11’36 of carbonic anhydride, and 2'32 of water. The 
“ carbonate of ammonia” of the Pharmacopoeia, being an irregular compound, 
might also require a statement of its percentage composition, in place of the 
omitted formula. It contains 28'81 parts of ammonia, 55‘93 of carbonic an¬ 
hydride, and 15‘26 of water. The formula given for the well-known double 
salt “ alum” might be advantageously omitted, as it represents the potash 
alum, which is no longer a commercial article. The definition also applies to 
potash alum, and not to the ammonia alum now used in pharmacy. The 
double tartrates and double citrates are perfectly individualized by their 
names, characters, and tests, and their formula? might be safely omitted. 
The same remark applies to the ammoniated salts which are prescribed as 
tests in the Appendix. 
Miscellaneous Compounds .—The remaining compounds for which chemical 
formulae are given in the present British Pharmacopoeia are the alcohols and 
ethers, the alkaloids, the sugars, santonin, pyroxylin, and the substitution- 
products named “ammoniated mercury” and “sulphate of indigo.” The 
names and descriptions of all those compounds are unambiguous, and their 
formulae might be safely omitted. 
4, Norman Terrace, Stockwell, S. 
Mr. Carteighe feared that it was now too late for the forthcoming edition of the 
Pharmacopoeia to be affected by the arguments adduced by Mr. Brough, although their 
cogency was indisputable. He trusted, however, that future editions of that work 
would be freed from the incubus of all theoretical formulae. 
ON A NEW MACEEATINO APPAEATUS. 
BY MR. E. W. GILES. 
The unostentatious arrangement exhibited before the Conference, for the 
