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Page:Popular Science Monthly Volume 35.djvu/444

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THE POPULAR SCIENCE MONTHLY.

One of the simplest patterns is produced by the tracing point rapidly revolving in a circle, while the glass slowly turns round on its axis. Another well-known pattern is traced out by a rather complicated mechanism, in which, by means of wheels having cogs along half their circumference, the tracing points are made to move up and down, and the glass to turn round, alternately, in a series of jerks. Although most of the patterns on glass are etched in this way, they lack the sharpness of definition required for the very best engravings. These latter are therefore carefully ground by hand, very small rapidly rotating wheels covered with fine rotten-stone powder being used to cut out the pattern on the glass. A large number of wheels of different shapes and, sizes must be used for the various details of a complicated design, such as a bunch of flowers and fruit, and this method is only resorted to in the case of the most expensive dessert sets, as it involves a considerable amount of skilled workmanship. With regard to the embossed patterns, so common on butter-dishes and similar articles, these, as well as the lenses used in lighthouses, are formed by pressing the molten glass into molds of the desired form. The flutings and ribbings on decanters, and the familiar lozenge or diamond patterns on cruets, are carved on the glass by means of grindstones, whose edges are rounded, angular, or flat, as the case may be. In the preliminary grinding, rotten-stone and water are used, but for the final polish the finest putty powder is required.

 

Roman Wines.—The increase in late years of the wine production of the province of Rome has been attended with great improvements in the quality of the wine produced. The principal group of wine-making districts is that of the "Castelli Romani," the wines of which are robust and durable. The land is of volcanic origin, and the ancient Roman rules of cultivation are followed. The cultivation of the white grape is giving place to that of the black, with a corresponding change in the color of the wine. The wine is kept in caves that consist of long corridors or galleries hewn out in layers of tufa, and having lateral niches, in each of which a butt is placed holding between eight and twelve hectolitres. The caves are ventilated by means of wells, and even in the height of summer the wine is thus kept at a very low temperature. The Government exercises strict measures against adulteration; and this is held to include the addition of any substances that are not found in pure wine, or the use of which is not in accordance with the rational principles on which wine-making is based. The addition of substances naturally to be found in wine is also considered as adulteration, if the substances are beyond the just proportions existing in pure wines. An exception is made in the case of gypsum, for which the maximum quantity to be permitted is determined by the Superior Board of Health.

 

Lead-Poisoning.—Several cases of lead-poisoning, caused by the preparation of homemade wine in earthenware dishes coated with litharge glazing (oxide of lead) have recently been noted in the London "Lancet." The symptoms were the appearance of a bluish line around the gums, vomiting of bile in large quantities, obstinate constipation, and constant abdominal pains. On analysis of some cherry-wine, from the use of which one of the cases had arisen, lead, in the form of sulphate, was found in very dangerous proportions.

 

Getting to Sleep.—Among the many recipes that have been given for overcoming wakefulness is one devised by a Mr. Gardner, and formerly celebrated in England, but now almost forgotten. It is to lie on the right side, with the head so placed on the pillow that the neck shall be straight; keeping the lips closed tightly, a rather full inspiration is to be taken through the nostrils, and the lungs then left to their own action. The person must now imagine that he sees the breath streaming in and out of his nostrils, and confine his attention to this idea. If properly carried out, this method is said to be infallible. Counting and repeating poetry are other means that have been recommended. Combing the hair, brushing the forehead with a soft shaving-brush, or fanning, are all good sleep-inducers, and might well be tried on sleepless children. To these may be added the Spanish practice of getting a baby off to sleep by rubbing its back with the hand. A sensation of dry, burning heat