Should we have the ill-fortune to be half-drowned, suffocated by unwholesome gases or vitiated air, or to fall down in a fit, Dr Woillez is ready with his new apparatus for artificial respiration. The patient's person, all but the head, is placed in a cylinder of iron, from which one stroke of a powerful pump extracts the air; the lungs and chest of the sufferer expanding as the vacuum is formed. Eighteen such mechanical breathings can be produced in the minute, and at each of these a quart of air—double the quantity inspired in normal health—rushes in to oxygenate the blood. The spirosphore is beyond all doubt a potent agent in serious cases, but some cautious surgeons have expressed fears as to the secondary results which might attend its use.
Nothing but praise can be bestowed upon the successful efforts of M. Lenoir to construct a looking-glass which should neither grow yellow, and give us back a bilious presentment of ourselves as silvered mirrors do, nor destroy the health of the workmen, as was the case in the old process of mercurial amalgamation. The new glasses are backed with silver, washed with quicksilver certainly, but in solution not in vapour, and therefore innocuous to those who handle it.
Alcohol, as we know, can be distilled from almost anything; but Apothecary-Major Ballard, of the Cherchell Hospital, in Algeria, deserves some notice for finding out that Barbary figs, so called, will yield it in profusion and of excellent quality. The stoniest tracts of North Africa are indeed dappled with the flaming red blossoms of the prickly pear or cactus, and the fruit, guarded by its thorny envelope, can be had for the gathering. One ton and a half of these wild figs will give about sixteen gallons of colourless alcohol, at eighty-five degrees, and with a kirschwasser flavour. The same weight of beetroot yields but fifteen gallons of the far weaker spirit in common commercial demand; while beetroot, an exhausting crop, can only be grown on the best and most highly cultivated land.
The most enthusiastic advocates of ballooning would have hesitated to declare that submarine surveys were within the province of the aëronaut. Such, however, seems to be the case, since M. Duruof and his companion going up in a balloon, on the twenty-fifth of last August, at Cherbourg, and being at an altitude of five thousand feet, were amazed to see beneath them, with startling distinctness, every rock, fissure, and depression at the bottom of the sea. And yet the sea opposite Cape Lévy, where the aërial voyagers obtained this bird's-eye-view, has an average depth of above two hundred feet. So limpid did the water appear that the under-currents were perceptible, whilst nothing would have been easier than to sketch or map the bottom of the sea.
A novel and perhaps a practically useful property of madder, hitherto only known as the active principle of a red dye, has been found out by M. de Rostaing. Meat covered with a layer of dry madder powder defies decomposition. It dries, however, slowly, wasting by desiccation so much that in the course of months it is reduced to less than half its weight. A more economical means of preserving meat is that employed at Buenos Ayres, whence beef, mutton, and even entire animals are constantly forwarded, in a state of perfect conservation, to Antwerp and Havre. The solution in which the meat is steeped contains borax and boric acid, saltpetre and a little salt, borax being the prime agent. The experiments of M. Dumas prove that borax destroys the soluble atmospheric leavens which would otherwise promote decay; and so far so good. But another savant, M. Peligot, who has dosed the plants in his garden with borax and killed them very promptly by so doing, suggests an ugly doubt as to the perfect wholesomeness of meat steeped in borax as an article of diet.
In spite of all the progress that has been made in electric science since first Volta put together his 'crown of cups,' a perfect galvanic battery is yet to seek. M. Onimus has done something towards this in availing himself of the virtues of the new, tough, and supple material which bears the name of parchment-paper. Every electrician knows that the great theoretical merits of Professor Daniell's 'constant' battery are counterbalanced by the trouble, care, and annoyance which it entails. All double liquid batteries have hitherto proved bulky, vexatious, and expensive; but M. Onimus simplifies matters by using parchment-paper instead of a porous cell, the copper spiral encircling the parchment, which is wrapped around the cylinder of zinc, and the pair of elements being simply plunged into a solution of sulphate of copper.
M. Leclanché, whose battery has for years past set in motion half the electric bells of Europe, has put what he considers the finishing touches to his well-known invention. He now, to compose his negative element, adds to his mixture of peroxide of manganese resin and hard gas-charcoal finely powdered, about four per cent. of the bisulphate of potassium, wedges the mass in a steel mould capable of enduring enormous pressure, and brings it first to a dull red-heat, and then under the action of the hydraulic press. We are assured that one cell of the improved Leclanché battery can heat a platinum wire to redness. A single element of Grove's or Bunsen's arrangement can do no more than this; and the result is the more creditable to the ingenious Frenchman that his is a 'constant' battery, excited by one fluid (the muriate of ammonia), and in which the consumption of zinc, always an important item, has been reduced to a minimum.
What we call vegetable isinglass, and the Chinese by the name of thao, and which has hitherto been derived from Eastern Asia, is now extracted from French sea-weed, and made useful in French factories. It is in its crude state a yellowish gelatine, which the Industrial Society of Rouen has, after repeated experiments, succeeded in converting into what bids fair to be the best sizing for cotton cloths ever known. Macerated in water for twelve hours, boiled for fifteen minutes, strained, and stirred till it is cold, the thao gives a clear solution, which does not again become a jelly, and which can be laid cold upon any textile fabric, and left to dry. One invaluable property it has, since it defies, at common temperatures, damp and mildew; and is therefore already being applied to give lustre, not only to Rouen prints and Mulhouse muslins, but to the woollens of Puteaux and the silks of Lyons.
Ozone, the newest and the least stable of the gases, has recently been made to do good service in the sick-room. It makes short work with those miasmata and organic impurities of vitiated air which the Italians describe by the expressive name of malaria, and which every physician knows to be among the most baneful influences with which the convalescent patient, whose tenure of life is not yet quite assured, has to contend. A mixture should be made of permanganate of potash, peroxide of manganese, and oxalic acid, in equal parts, and two large spoonfuls with some water put into a plate and placed on the floor of the sick-chamber. Care should be taken, however, to remove steel fenders and fire-irons, and to cover up brass door-handles, since ozone will rust all metals meaner than gold and silver.