Page:Popular Science Monthly Volume 32.djvu/738

 Disinfection by Heat and by Steam.—Dr. II. F. Parsons has found, in experiments on the disinfection of packages by heat and by steam, that dry heat at the boiling-point for an hour is sufficient to destroy active bacilli of all ordinary infectious diseases; but, if spores are to be attacked, a heat of 245° for an hour or of 220° for four hours will be required. The complete penetration of an object by steam-heat for more than five minutes is sufficient for its full disinfection; and this method is applicable to such articles as pillows, which are very difficult of penetration to dry heat. Moistening the air of the heated chamber diminishes the time necessary for penetration, while it also makes the distribution of temperature through the chamber more agreeable, and tends to prevent the scorching of articles placed in it; but it was not found to increase the disinfecting power at the temperature employed. Damage may be done to articles in disinfecting them by heat or steam, by scorching or partial de-composition of organic substances; by fixing of stains; by melting of fusible substances; by changes in color, gloss, etc.; by shrinking and felting of woolen materials; or by wetting. The nature of the articles should, therefore, be regarded in adapting the process to them.

English Taxes.—The first recorded tax imposed upon Britain was laid by Julius Cæsar, who, after his victories, required for Rome an annual tribute of men and wild animals—the men to be kept as hostages, the animals to be fought with in the arena. When ecclesiastical domination came in, the Pope levied a "Peter's pence" for the support of his English University at Rome. When the English conquered Wales, they levied on the people an annual tax of three hundred wolves' heads, which proved a great blessing to the principality. After England became exposed to great danger from the incursions of the Northmen, a land-tax of twelve pence per "hide" was levied in order to raise a sum with which to buy off the invaders. The consequence of this silly policy was that more invaders came to be bought off. A poll-tax was imposed in the fifteenth century of one shilling a year upon every person, except he belonged to the clergy, above the age of fifteen years. This was distasteful to the people, and led to rebellion. In another form of taxation, laborers and tradesmen were required to give their services to the king or to a noble. Many palaces, Windsor Castle among them, were built in this way. From 1695, for thirteen years, every person not a pauper was required to pay a tax for each child born to him, rising from two shillings in the case of a common person to thirty pounds in the case of a duke. A bachelor's tax of one shilling in the case of ordinary persons was imposed on unmarried men over twenty-five years old, and on widowers without children, but wealthy people and nobles had to pay more. By Queen Elizabeth's act of uniformity, persons who refused to become Episcopalians, or who absented themselves from church on Sunday.«, had to pay a tax of a shilling a year. Perhaps the most oppressive and impolitic taxes imposed by the British Government were those on windows and on funerals, with which even the history of this nineteenth century has been blotted.



second ten days of January were extraordinarily cold all through the North-west, and temperatures were registered at some places much below what had ever before been observed in the United States. At Iowa City, according to Professor Hinrichs, the mercury was at or below zero every night from the 11th to the 20th. During the twenty-eight years that weather observations have been taken, there have been only five decades having a mean temperature of zero or below; only one of these was during the first eighteen years, while the other four were during the last ten years. This shows that extreme cold has been seven times more frequent during the latter than during the former years, and is another indication of what the author has often held, that the later winters in Iowa have been colder than the former ones.

has been successfully tried in the Seine for stopping boats. The apparatus is a cable, having on it a series of canvas cones, which open out by the action of the water, and close again when drawn the usual way. A steamer running thirteen knots was stopped each time by the apparatus in thirteen seconds, and in a space of from twenty to thirty feet. 