HOW THE DEADLY ARSENIC IS OBTAINED.

Rodney and Otamatea Times, Waitemata and Kaipara Gazette, 11 September 1912, Page 7

HOW THE DEADLY ARSENIC IS OBTAINED.

The most easily administered of poisons, and, until comparative' recent j years, the least easily detected of them all, it is l little wonder that arsenic should have played so important a part in the annals of crime. That it still does so is more to be marvelled at, for,> thanks to the great strides made in scientific research during- recent years, infallible tests may now be applied which will reveal the presence. of arsenic in the organs of the body, even though, several years may have elapsed before the finger of suspicion indicates the commission of some dark deed. The reason for its popularity, from the poisoner's point of view, is apparent in the fact that arsenic mixes readily with food, and, unlike other poisons, has no taste other than a slightly sweetish savour, which is not at all unpleasant (and which, mixed with food, passes unnoticed) and, moreover, in the fact that it has no smell. Commercial Uses. Sinister as is the vision usually associated in our minds with arsenic, the uses to which this mineral poison is put are many and varied. As a medicine ft has proved of immense value in certain cases ; it is mixed with *cad in the manufacture of shot; it enters into the composition of certain kinds of glass, and is largely used in the making of aniline dyes. The world's supply of this deadly poison is drawn very largely from the mines of Cornwall and Devonshire, from which district something like six hundred tons of arsenic a month were forthcoming- during-' the first years of the industry, established rather over thirty years ago; but the yield has since then been greatly reduced. Prior to the recognition of its commercial uses, the arsenic resulting from the smelting of the tin ore (for tin not freed from arsenic is of little' value) was disposed of as refuse, and anybody willing to cart it away from j the mine was quite at liberty to do so —and welcome—the stuff so carted • away being generally used for purpoi ses of road-mending. With the intro- ; duction of the industry, however, all ithis was changed. The "rubbish," it was now found, was of even more value than the tin, I and whereas the ores were originally j burnt for the sake of the tin or cop- ! per, they were now burnt rather fqr the arsenic contained therein. "Refuse" heaps throughout the ore-bear-ing district were n6w carefully raked over, roads were torn up, and abanjdoned mines were re-opened at tremendous cost for the sake of this saro*=> hitherto discarded product. A Safe Occupation. "And, after all, what is arsenic?" you ask. ( Well, arsenic has been described as white soot. Arsenic in its natural state ' is contained in the stones, or ores, and these as they come from the mines are J crushed to the consistency of fine j gravel, which gravel is then shovelled j into a furnace to be calcined. The fumes generated by this roasting process would deposit upon any object held therein a greyish film, which can be scraped away in the form of a grey powder, and here you have the crude arsenic. To obtain the commercial product, refined arsenic, as it is called, this crude arsenic is roasted yet again, which frees it from the carbon and other unwanted ingredients which it contains. Fortunately, the manufacture of arsenic is practically unattended with danger where ordinary precautions are observed, and one hears little or nothing of any serious injury befalling the workers.