MISCELLANY. 
351 
two ounces, put this on to a fresh filter, on which has been placed some 
animal charcoal with a few grains of powdered chloride of barium ; evapo- 
rate the filtered liquor until the product left to itself presents the appear- 
ance of flakey crystals of a brilliant whiteness, which when dried, must 
be kept in a well-stopped bottle — Journ. de Chim. Med. 
Hyposulphite of Soda. — Berzelius proposes the following as a simple 
and easy method of preparing the hyposulphite of soda, now extensively 
used in photography: 
Saturate a solution of carbonate of soda with sulphurous acid gas, so 
as to form a bisulphite of soda. Boil a weak solution of hydrate of soda 
with sulphur to saturation. Add the latter solution to the former until 
there shall be a slight excess of sulphuret of sodium ; filter, evaporate, 
and crystallize. The salt thus obtained, when freed from the mother- 
liquor, will be hyposulphite of soda. 
Lond. Pharm. Journ. and Trans. 
Sialagogues. — Dr. Samuel Wright has published an elaborate and 
learned essay on the Physiology and Pathology of the Saliva, in the Lon- 
don Lancet. Among other matters he enumerates, incidentally, the va- 
rious medicinal substances, which, in addition to mercury and its com- 
pounds, have been known to induce salivation. Although the fact is well 
understood concerning most of them, yet it may be useful to enumerate the 
whole in consecutive order. 
1. Iodine and its salts sometimes act as remote sialagogues. Authori- 
ties. Carro, quoted by Bayle; Dr. Manson, Cogswell's Essay on 
Iodine. 
Hydriodate of potash has induced ptyalism, as observed by Drs. Clen- 
denning and Wallace, and Dr. Wright himself. Cantu, Coindet and 
Gairdner have detected iodine by chemical tests, in the saliva of persons 
who are taking it, 
2. Chlorine. — The continued use of chlorine wafer is said to have caused 
salivation. Pereira. 
3. Bromine. — Dr. Glover produced ptyalism in dogs and rabbits by the 
administration of single poisonous doses of it. 
4. Digitalis. — A case is recorded in Rust's Magazine, in which the 
salivary discharge continued for three weeks. Other authorities. Wither- 
ing, Christison, Barton, 
5. Hemlock — The injection of a watery solution of hemlock into the 
veins of a horse has been known to produce salivation (Moiroud.) Dr. 
