Cassius. Zsigmondy says, "I look upon the knowledge that a mixture of colloid bodies can behave, under some conditions, as a chemical compound, and that the properties of one body in such mixtures can be hidden by those in another as the most important conclusion to be drawn from this work."
The Abuse of Unskilled Labor.—The number of diseases directly or indirectly due to continued long standing is especially numerous among women. The London Lancet, which nearly twenty years ago attempted to improve matters in this respect in the case of shop-girls, has again taken up the subject, and recently published an editorial urging customers of the shops to boycott those establishments where no sitting accommodations are provided for the clerks. It says: "We, as medical men, maintain that sitting accommodations are absolutely necessary for shopgirls. The only argument having even the semblance of legitimacy which we have heard put forward in defense of the nonprovision of seats is that sitting is conducive to idleness, but in this connection such a premise can not be permitted, for an employee would be bound to come forward when an intending purchaser entered the shop.… The very fact that in many shops she is not allowed to sit down is conducive to idleness—idleness of the worst kind, the idleness of pretending to do something while in reality nothing is being done. Can nothing be done to stop this—as we once called it without the least exaggeration or sensationalism—'cruelty to women'? To the true woman—the woman with feelings for her sisters, the woman of love and sympathy, the true woman in every sense of the word—we appeal for help in this matter. If such women would abstain from purchasing at shops where they see that the employees are compelled to work from morning till night without permission to rest from their labors even when opportunity occurs, we should soon see the end of a practice which ruins the health and shortens the lives of many of our shopgirls." That there is a certain amount of danger for women from long-continued standing, to the point of exhaustion, there is no doubt, and much can be done toward improving the present conditions in this respect and in other hygienic ways in the shops. The large influx of women during recent years into the counting-room and the salesroom gives such questions an increasing importance, especially in the less skilled positions where labor combinations for mutual protection are not possible. There has already been considerable agitation of the question in this country, and there still remains much to be done. But, as Lord Salisbury pointed out in causing the rejection of a bill for remedying present shop conditions in England, it is a question not suitable for legislation, and can only be settled through the indirect action of public opinion on the shopkeeper himself.
The Occurrence of Gold Ores.—The following paragraphs are from an article by H. M. Chance in the Engineering Magazine for July, entitled The Increasing Production of Gold: "Another reason for anticipating further increase in the production of gold is found in our better knowledge of gold ores, and of the conditions under which gold occurs in Nature. Until the discovery of the Cripple Creek district the occurrence of gold as tellurid in deposits of large extent and value was practically unknown. Gold was, of course, known to occur, sparingly in some ores, partially as a tellurid associated with other minerals; but such a mineralized belt as that at Cripple Creek was entirely unknown, and such deposits were not looked for by the prospector. Similarly, we now know of another class of gold ores in which the gold occurs apparently in some form chemically combined in a siliceous matrix, often approaching a true jasper or hornstone, and showing by analysis possibly ninety-five per cent of silica. Such ores show no trace of 'free' or metallic gold, and the presence of gold can be determined only by assay or analysis. A few such discoveries have recently been made, accidentally, by inexperienced persons, who had rock assayed from curiosity. Similarly again, in the last few years gold has been found in most unpromising-looking porphyry dikes—the very rocks prospectors the world over have regarded as necessarily barren because they almost invariably fail to show any 'free' or metallic gold by the miner's quick 'horn' or 'pan'
