The difference between the chlorine-free and the chlorine-containing oxalic bases are summarised as follows:—

FROGS.
Chlorine-Holding Bases.Chlorine-Free Bases.
Notable narcosis; no heightened reflex action, muscular cramps, nor spontaneous convulsions.Narcosis occurs late, and is little pronounced; a notable increase of reflex excitability; more and more muscular paralysis; between times, muscular cramps.
CATS.
Notable narcosis and salivation; no mydriasis; convulsions and paralysis; no change in the respirations.Great excitement; general shivering, rising to pure clonic convulsions; paralysis of the hind legs; notable mydriasis, jerking, and superficial respiration; weak narcosis.
DOGS.
Notable narcosis; occasional vomiting; the rest as in cats.Narcosis evident; the rest as in cats.

PART IX.—INORGANIC POISONS.

I.—PRECIPITATED FROM A HYDROCHLORIC ACID SOLUTION BY HYDRIC SULPHIDE—PRECIPITATE YELLOW OR ORANGE.[700]
Arsenic—Antimony—Cadmium.

[700] Fresenius has pointed out that sulphur may mask small quantities of arsenic, antimony, tin, &c., and he recommends that the turbid liquid in which apparently nothing but sulphur has separated should be treated as follows:—A test-tube is half filled with the liquid, and then a couple of c.c. of petroleum ether or of benzene added, the tube closed by the thumb, and the contents well shaken. The sulphur dissolves, and is held in solution by the solvent, which latter forms a clear upper layer. If traces of a metallic sulphide were mixed with the sulphur, thin coloured films are seen at the junction of the two layers, and the sulphides may also coat the tube above the level of the liquid with a slight faintly-coloured pellicle (Chem. News, Jan. 4, 1895).

1. ARSENIC.