SCIENTIFIC ITEMS.

Lyttelton Times, Volume LXVIII, Issue 8323, 10 November 1887, Page 3

SCIENTIFIC ITEMS.

TEMPERING STEEL WITH ELECTRICITY. At the shop of the Sedgwick Mainspring Co., 19 and 21 South Canal street, Chicago (says the West Electrician ) can be seen a very interesting application of electricity to the arts. It consists of tempering watch springs by means of the electric current. In one part of the room stands what is known to the trade as a onelight dynamo. The conductors from the dynamo lead to another part of the room, to a bench on which stands an ordinary oil tempering bath. One of the conductors connects with a point within the oil bath, and th® other to a point without. The piece of flat soft steel wire that is to be tempered to the blue colour is fed under the contact point on the outside of the bath first and then under the one on the inside. When it reaches the latter the circuit in complete, and the wire immediately and uniformly becomes heated. No means have been taken to measure the current exactly for the purpose of doing the whole work mechanically. The variation in the percentage of carbon in different pieces of steel forbids the delicate process of tempering from becoming a purely mechani cal piece of work. Therefore, with the electric current as with a fire, the colour of '.the stool determines the length of

. ...iMugaßnmgimagMM,mu win time that it shall be heated. Several advantages are claimed for this process of tempering. The chief one is that the . steel does not have time to oxidize after it has been heated to the proper colour before it is under cover of the oil, and consequently that the steel wire is of the same thickness when it is tempered as it was before it entered the process. The heating is uniform throughout the length of the spring, and there is less liability of defective spots. The process is a rapid one, the springs being heated and passing into the bath at the rate of four inches a second. The large watchmaking concerns look with great favour on the new process, and the Sedgwick Mainspring Company are just about to double tbeir capacity for the purpose of keeping up with their orders. WEIGHT CAEEIED BY GEEHAN INEANTET. The maximum and minimum weights in the new approved forms of equipment to be supplied to the German infantry have been arranged by the authorities at Berlin. The Bavarian forces, as usual in most of the military innovations made of lata beyond the Ehine, will he suited first, and although the fact is clear, the reasons for the warlike preparations in this kingdom before the rest of Germany are not immediately apparent. The heavier burden of the equipments of two sizes, it is expressly stated, is only to bo served out to men whose physical conformation and powers are found superior to the average, a disposition in itself a proof of the extreme care and solicitude of the German commanders for their followers in the ranks. Taking the basis of 28 grammes to the ounce, and 428 grammes to the English lb, the weights of the different items of equipment can be closely determined: Knapsack and fittings, of maximum scale, 1170 grammes ; belt, waist plate, and frog for bayonet sheath, 399 grammes; three cartridge pouches and straps, 1015 grammes; pair laced shoes, 1200 grammes; helmet and mountings, 495 grammes ; camp utensils, 735 grammes; brushes and housewife, 600 grammes; and biscuit bag, 800 grammes; or 6514 grammes in all. But to estimate the full weight carried by the German infantryman in heavy marching order must be added his rifle, which weighs 4600 grammes; 100 cartridges, 4300 grammes; and the bayonet and sheath, 900 grammes. Spare under linen, socks, greatcoat, and boots, with camp or service tools and bread, may be counted for 17 kilos, to give an aggregate of 23 kilos 300 grammes. If the odds and ends—not included in the regulation kit, which every soldier possesses—are taken into account, the lump burden may be calculated at the average of 25 kilos, or 551 b 3oz English. THE “HOELA’s” ASCENT. The ascent of the balloon Horla, under the direction of M. Jovis, took place at an early hour on the morning of August 13, iu the presence of about 400 people. The work of inflation was commenced at the La Vilette gasworks shortly after four o’clock, while the car was being laden with a selection of scientific instruments of various kinds, 400 kilos of ballast, three small balloons containing oxygen for inhaling, if necessary, two guinea-pigs for experimental purposes, two pigeons, &c. It was half-past six before the balloon got filled to its capacity of 6500 cubic metres of gas, and a few minutes after seven M. Jovis took leave of his wife and child, and stepping into the car with M. Mallet, gave the order to let go. The balloon ascended slowly, and soon took a north-west direction until another current carried it eastward, and it became lost to view a little after eight o’clock. Its altitude at that moment was variously estimated at from 9000 ft to 12,000 ft. In the afternoon a telegram, dated Baconfoy, received by the Aeronautical Union, announced that the descent had been with difficulty effected in the Forest of Pregre, near the Villa St Hubert, belonging to the King of the Belgians, in Luxemburg. M. Jovis stated stated that they had reached an altitude of over 21,000 ft, but M. Mallet had swooned twice. Their ballast having given out, they had been unable to ascend any further. Though the scientific results of the ascension are not yet known, M. Jovis has given some information from the notes ie took during his aerial journey. The two guinea-pigs did not suffer ia any way, but one of the pigeons fell in suspended animation in its cage at the altitude of 6000 metres, and only recovered after the descent. The other pigeon, let loose at 5000 metres, has not reappeared, and must either have succumbed from the effects of the ascent, or been chased by sparrow-hawks, which happened on a previous occasion. The balloon descended in the forest of the Ardennes, the guide rope and its anchor catching in an oak, and the aeronauts alighted without great difficulty. Nevertheless, when he touched the earth, M. Mallett fell, and remained lying on the ground in an exhausted condition till the balloon had been emptied of its gas. The Horla, which left the Vilette at seven o’clock, was driven westward. At twenty * minutes to ten, the balloon had returned, and was high in the air above Villette. At twenty minutes to nine, the balloon was at an altitude of 4800 metres, and at a quarter past nine 6000 metres. By twenty minutes to ten they had risen to the height of 6600 metres; and at ten, when the balloon had risen 50 metres more, M. Mallett fainted. M. Jovis relates that he brought him to by administering oxygen gas. Though Mallett had almost lost consciousness, he would not hear of descending, and told Jovis to go higher, so the last ballast was thrown out of the car. At ten minutes past ten the aeronauts had reached the height of 7000 metres, aud Mallet seemed better. Jovis maintains he feltno inconvenience whatever. The two men conversed, and found their vocal organs had experienced no alteration, and their dynamometric strength was the same as when on the earth. The descent then began. At twenty minutes past ten the balloon had descended to 5930 metres, where it was surrounded by compact masses of cloud. From that moment the descent was extremely rapid. At twenty-four minutes past ten the aeronauts were at 4005 metres, and a single minute later at only 3850 metres. Both aeronauts were, so to say, dazed by the vertiginous rapidity of the fall. Jovis acknowledges he could no longer distinguish anything. At eleven o’clock the balloon fell in the forest, both men being in a completely exhausted condition. Jovis says he had so far lost his reckoning that he imagined himself to be in the Department of the Seine-et-Mame. As the crow flies the distance between Paris and the spot near St Hubert where the balloon touched the ground is about 380 kilometres (233 miles), and Jovis considers that with the course travelled by the balloon, driven in different directions by the currents of air, the real distance travelled in four hours was not less than 500 kilometres. Two aeronauts, who are well known both-in France and England—Messrs Capazza and Gaston Tissandier—have been asked to express an opinion on the ascent just made by Messrs Jovis and Mallet. They both contend it is not difficult to reach a height of 7000 metres. According to Capazza, who says he would willingly go up to that height every day as a morning promenade before breakfast, the real difficulty does not commence before 8000 metres ; and Tissandier agrees with him sb'far as he puts the distance of the beginning of difficulties at 7500 to 8000 metres. Tissandier declares he is ready any day once more to ascend 8000 metres, hut he would not care to go higher. It will be remembered that he was the only survivor of the ascension made in the Zenith on April 15, 1875, and in which. Croce, Spinelli, and Sivel lost their lives. The Zenith, rose to an altitude of over 8600 metres. Capazza, who is famous for having crossed the Mediterranean in a balloon from Corsica to France, affirms that Jovis could never have imagined he would reach 8000 metres in a balloon so small as the Horla. It was, ho contends, quite impossible.— Standard.