Note 813 — PART IX.—INORGANIC POISONS. (continued 2)
Reading edition
According to Fresenius (Zeitschr. f. anal. Chem., i. 445), a solution which contains 1⁄10000 of its weight of antimony, treated in this way, gives in two minutes a brown stain, and in ten a very notable and strong dark brown film. When in the proportion of 1 to 20,000, the reaction begins to be certain after a quarter of an hour; with greater dilution it requires longer time, 1 to 40,000 giving a doubtful reaction, and 1 to 50,000 not responding at all to this test.