Popular Science Monthly/Volume 18/December 1880/Notes

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Mr. Rogers Field, in a recent lecture on house-drainage at the Parkes Museum of Hygiene, condemned all forms of water-traps as a means of excluding sewer-gas from dwellings, on the ground that they allow the gases to pass through them by the water absorbing it on one side and giving it off on the other. In his opinion, the only sure way to keep these gases out of the house is by thorough ventilation and disconnection. Efficient ventilation moans a continuous current of fresh air through the drains and pipes, but even then perfect security can only be obtained by cutting off direct communication between the sewer and the house-drains.

The last annual report of the New Haven Board of Health contains a valuable letter addressed to the Common Council of that city, by the President of the Board, Professor William H. Brewer, of the Sheffield Scientific School, setting forth in a forcible way the financial advantages of a thorough system of sanitary administration in towns and villages. This letter should be in the hands of all the village trustees in the land, many of whom may be reached by money considerations when mere questions of life and death would scarcely arrest attention.

In its crusade against the London shop-keepers for obliging their saleswomen to stand continually during business hours, the "Lancet" is disposed to lay a part of the blame on the patrons of these establishments. It thinks if there were any real sympathy, on the part of the public, for the young persons who are made to suffer by the system of standing, it would long ago have been brought to a summary close. We sometimes hear of women having a special faculty for nursing the sick: they should show in this matter that they have the humanity to avoid the creation of needless disease.

Mr. Nilson has prepared a quantity of the oxide of the new metal ytterbium, or ytterbine, and finds the atomic weight of the metal to be 17·301. Ytterbine appears in the state of an infusible white powder of a density of 9·175, insoluble in water, but easily dissolved in acids, even when diluted, at a boiling heat; but, when cold, they attack it with difficulty, even if concentrated. The solutions are colorless, and show no absorption rays in the spectrum. The earth and its salts do not communicate any color to flames; but the chloride gives a very bright spectrum with the electric spark.

A new remedy for neuralgia has been introduced into England from the Feejee islands. It is called tonga, and is brought in the shape of fragments of woody fiber, bark, and leaves, broken up into pieces so small as to make it hard to identify them botanically, mixed and done up into balls of about the size of an orange. To prepare it, the ball is soaked in cold water for about ten minutes, when the infusion is drawn off and a claret-glass of it is taken three times a day. The ball is then dried and hung up, and can be used over and over again for a year. The principal constituent of the remedy appears to be the stem of a species of Raphidophora.

M. Lortet, who has been studying the fauna of the Lake of Tiberias, reports that its surface is 212 metres (689 feet) below the level of the Mediterranean, and that its greatest depth, which is at the northern extremity opposite the upper mouth of the Jordan, is 250 metres (812 feet). On both shores of the lake are terraces covered with rounded pebbles, rising to a height which indicates that the level of the lake was once the same as that of the Mediterranean. He believes that the waters of the lake were formerly very salt, more so than sea-water, but not so excessively salt as the waters of the Dead Sea, and that they have been freshened since the level of the lake was lowered by volcanic convulsions, by the flow of the Jordan, till they have become drinkable.

Professor Schneltzler, assuming that the color of flowers is due to the combination of different chemical elements in their tissues, has shown by experiment that when an alcoholic extract of the color is made it is enough to add to it an acid or alkaline substance to cause it to exhibit any of the colors which plants present. Flowers of the peony, for example, give a violet liquid in alcohol; if salt of sorrel is added to this liquid, it will turn a pure red; soda produces, according to the quantity that is added, violet, blue, or green.

Those in pursuit of the marvelous may learn a grain of caution from the following, taken from an article on "Living Toads in Stone" by Mr. Thomas G. Denny, in a recent number of "Science Gossip": "Most of us have heard of 'Flint Jack,' but I do not think many readers of this journal have met with any manufacturers of fossil toads; but I knew many years ago a working naturalist living in Leeds who used to prepare for sale toads, stated to have been found in beds of coal, by baking them perfectly black and hard in an oven, and then taking square pieces of coal and, after splitting them carefully, he would cut a hollow in each portion to receive the 'ancient reptile.'"

Mr. Frederick Ransome has succeeded in producing a good hydraulic cement from the slag of blast-furnaces. His process, which is applicable to almost any quality of slag, has the advantage over previous methods of making cement, that while in them the materials, lime, silica, and alumina, had to be brought together and carefully combined, in blast-furnace slag the combination has already been completely effected before the slag has left the furnaces, and generally with the proportions of silica and alumina that are required. By mixing the slag with an additional quantity of lime and calcining the mass, a strong and reliable cement of an agreeable color is produced.

It has been affirmed, in proof of the theory that fat is formed from albumen, that the albumen of the cheese in the cellars of Roquefort is changed to fat by the action of a fungus found there. The assertion is disproved by experiments made by Herr Sieber on the cheese in these cellars, which show that the most marked change that cheese undergoes in ripening is the loss of water, and that the proportion of fat remains unaltered if only the dry substance be considered. A decomposition of the albumen also takes place, the caseine passing into a series of decomposition-products which are similar to products of putrefaction in the first stage of putrefactive fermentation, but the analyses show no transformation of albumen into fat.

Efforts to reduce monkeys to discipline have not very often been successful. A native of the province of Bengal has, however, trained several of them to work the cords by which the punka, or ventilating fan of India, is moved. They perform their task to perfection, and, thanks to their activity, keep the punkas in continuous motion, maintaining a constant, agreeable movement of air all through the room.

Dr. Henry Barnes records a case of an extremely severe attack of gout brought on by sleeping in a newly painted room. Three years before, the patient, an old man, had suffered a slight attack of the disease (the first of his life), but soon recovered, and, up to the time of this exposure, had been quite free from gouty symptoms. The introduction of lead into the system is given as the cause of the attack.

A company with large capital has been formed in Paris to work up an invention for coating thread with silk. The invention embraces, according to the "Bulletin des Soies," a chemical process for covering linen or other vegetable threads with amesh of silken matter in a manner similar to that in which metallic objects are plated with gold or silver. The process is dependent on the fact, which has long been known, that silk is soluble in several strong acid preparations.

The French Chamber of Deputies has voted a credit of fifty thousand francs to M. Pasteur to enable him to extend his researches upon the contagious diseases of animals. The labors of M. Pasteur during the last four years have already led to the discovery of the causes of carbonaceous affections, and the knowledge thus gained has been employed to prevent them in many cases. His present investigations are in relation to the character of virulent maladies in general.