Page:Popular Science Monthly Volume 38.djvu/883

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method of rendering the fugitive colors fast, must be answered in the negative. The fast or fugitive character of a color is an inherent property of the coloring matter used, and depends mainly, if not entirely, upon its chemical constitution. In order to improve the fastness of coal-tar colors we should examine thoroughly the characteristic of every coloring matter, then choose the fastest and reject the rest, or only employ them when they are perfectly admissible. Such a process of selecting the fittest has gone on in the past with reference to the dye-woods, and such is the sifting process now at work among the coal-tar colors. Side by side with this must run the selection of the most brilliant and most easily applied of the fast colors, so that the ultimate goal of perfection to which we would thus attain would be to have all our colors fast, brilliant, and easily applied. Given a good range of brilliant colors, it becomes possible by their varied combinations to produce the most peculiar, pleasing, and attractive shades of grays and olives and browns, and the thousand and one delicate tints beloved by the artist; and they yield when desired a richness and life and body of color compared with which older colors are poor and lifeless. Let the artist, inexperienced perhaps in the application and proper use of coal-tar colors, confine his attention, if he wishes, to the more somber and older dye-stuffs, but do not allow him to persuade you that there is no beauty or permanence or other quality of excellence in any of the coal-tar colors of to-day.


Prof. F. V. Riley takes a hopeful view of the promise of good results to come in apiculture from experiment and investigation. He pointed out, in his address last fall before the Society of Economic Entomologists, as one of the most inviting fields the search for new varieties or species of bees and their introduction; "for just as American apiculture has profited in the past by the importation of races like the Italians, Syrians, and Carniolans, there is every prospect of further improvement by the study and introduction of such promising races as are either known to occur or may be found in parts of Africa and Asia." The further study of desirable bee forage plants, and the introduction and acclimatization of such as are known to be valuable to parts of the country where they do not yet occur, are very desirable.

A new spice adulterant is described by Frank A. Hennesey, Ph. G., in The Pharmaceutical Era. It consists of ground crackers made from a very low grade of wheat—but little better than cattle-feed. The powder thus obtained is colored yellow with turmeric, black with charcoal, brown with Spanish brown and turmeric, etc., according to the spice it is to adulterate. The biscuits are made in a steam bakery in Philadelphia, and large quantities of them have been delivered to a certain spice house in the same city. The presence of this adulterant can not be detected except by a chemical analysis of some difficulty. Ordinary cracker dust has also been used for this purpose.

A correspondent of La Nature, from Bagdad, describes a shower of rain accompanied by a fall of "manna," that took place in August, 1890, around Mardeen and Diarbekir. A surface about ten kilometres in circumference was visited. The nutritious substance was picked up by the people and made by some of them into bread, which had a pleasant taste and was easily digested. A specimen of it sent to La Nature was in the form of spherules, about as large as millet-seed, agglutinated together; was yellowish on the outside and white within. It proved, after a botanical examination, to be a lichen (Lecanora esculenta), which, according to Decaisne, is common in the arid mountainous regions of the Tartarian desert, where it lies on the ground, distinguishable only by the most practiced eyes from the gravel with which it is mingled. Parrot told, in 1828, of a shower of it which fell in Persia, where it was collected by the people and was greedily eaten by cattle. The particles had probably been taken up by some whirlwind and separated from the accompanying sand while passing through the atmosphere.

A bold device, which will also furnish a new source of excitement, is suggested by M. Aristide Berges, a French engineer, in the shape of an elevator-car to fall, with its passengers, through a thousand feet, or the height of the Eiffel Tower. During its fall the machine will acquire a velocity of about 250 feet per second, or more than twice that of the swiftest express train. The car will be built in the form of a long cone, strengthened by inner cones which will act to prevent the sudden compression of the air within the chamber, and will be about thirty feet high. To break its fall, a well of water will be provided, 160 feet deep, into which the machine will descend, and sink so gradually as to remove the sensation of shock. A picture is published by the designer showing the car carrying fifteen people in its headlong journey.