SCIENCE NOTES.

Lake County Press, Issue 2637, 22 June 1916, Page 7

SCIENCE NOTES.

SERVIA'S MINERAL SPRINGS. One feature of Servia. which is little known but which one clay may make that gallant little country rich is its wealth of mineral springs. With some ' capital and enterprise several Serbian > spas might soon outdo the famous I watering-places of Austria and Ger- ■ many. One of them, Arandyelovats, ! has 'already attracted a considerable I number of visitors in recent years, but the baths at Kovilyacha have never re- [ ceived the attention they deserve. ; Waters of rare virtue are there—one • containing iodine for the scrofulous j rheumatic, another with iron, another , with peculiar potency for the euro of j eve diseases—such as might well make Ivovilyacha the finest spa in Europe, j WORKING POULTRY OVERTIME. A resident of Chicago is reported j to have devised a way to keep his i fowls up to their work during the j winter season, when tho short days have an undesirable effect on the pro- , due-turn of eggs. His plan is to pro- i vido his fowls with artificial light to ] work by, and ho has,, installed a series ; of lights to work in his hen house. J This is the way ho works his scheme. ' according to the Electrical Review: ■ :Vt six in the morning I turn on the j switch, and the fowls get up, think-) 'ing it is daylight. The lights are' turned off at daylight, when the neighbours' fowls are just arising. ! At four the lights are turned on again, and they are kept going until nine at night, when I turn out all j except the 2-candle'power lamps, j These give just sufficient light to give the appearance of dusk, and the' fowls begin to roost. 1 leave the small j lamps lit all night, so that if any of the! fowls want to get up at night to eat they can do so. Eleven days after j the lights were installed the daily I average jumped from 26 eggs to 83. ] ] During the moulting season under the ' old custom, when most of the food i was going to feathers instead of eggs, j I had only 11 eggs a day. Now 1 get 52 a day during the moulting. season. By'my method I keep the: liens thinking they are getting the' same amount of daylight all the year j round, and I am keeping them think-, ing all the time. ; NICKEL-PLATING ON ALUs' MINIUM. j A process for nickel-plating aluminium was recently described by I MM. Canae and Tassilly to the I Societe d'Encouragement pour I'lndustrie Nationale, as follows: The I aluminmui piece to be plated is passed through a boiling potash bath, then

d brushed with milk of lime, dipped in f a 0.2 per cent, potassium cyanide v bath for several minutes, and finally subjected to attack by an iron chloride solution—soo grammes hydrochloric acid, 500 grammes water, 2 grammes iron—till the appearance of the aluminimum resembles crystallised tinplate. After each stage in this treatment the work is thoroughly washed 1 in water. The following is found to 1 In* a satisfactory nickeling solution: • Water, 1,000 cubic centimetres; nickel chloride, 50 grammes; boric acid, 20 ' grammes, worked at '2.5 volts and I ampero per square decimeter. The deposit obtained is matt-grey on leaving the bath, but easily takes a good polish under the scratch brush. Above all, it is claimed that the coating will stand bending and hammering without peeling or cracking. The reason for the adherence of the deposit appears to lie in the strong reducing action of the nascent hydrogen evolved when the aluminium is plunged in the ferric chloride pickle. Metallic iron is deposited (in the aluminium, ami. though its amount is so small—o.2s to 0.5 gramme per square metre—that it cannot form a continuous inter- , mediate deposit, the iron forms with the aluminium a number of tiny couples favouring attack by the acid pickle. The surface of the aluminium is thus very minutely but very complctely pitted, so that, besides being deposited on the nearest practicable approach to a chemically pure surface, the nickel coating is actually locked or "rooted" into every part of the ! aluminium surface, and it is on this | mechanical action that the tenacity of

'< the deposit depends. A GIRL ELECTRICIAN. One of the most remarkable things in the replacement oi' men's labour by i women's, which is going on to-day, is j tlie great popularity which mechanical | work seems to bo' winning for itself i among women. It seems only yesterj day since practical mechanics even of I the simplest kind were still supposed ! to bo beyond even the grasp oi the female intelelct, and now to-day we ; have the "chaufl'euse" who can repair a car as well as any man, the woman driver of heavy transport lorries, and the skilled munition maker. Particular instances of women who are excelling in these branches of work, hitherto exclusively reserved for men, serve to show how great and rapid lias been the change. From Ireland comes the account of a young girl only just twenty years old who is doing the work of a skilled electrical engineer. She is Miss May Traill, the daughter of Mr. William A. Traill, C.F., a well-known engineer who was the constructor of one of the first electric tramways, the Giant's Causeway and Portrust Electric Tramway, which was opened in 1883. Miss Traill, who studied horticulture at Studley College, Warwickshire, passing fifth out of 135 candidates at the end of two years' course, exhibited her gift for mechanics while still a student, and as a result was made chauffeur of the collego motor lorry. When this was purchased by the Government she drove it from Studley to London, a distance of over 100 miles, and subsequently was placed on the staff of the college' in full charge of electric light and power installation. This consists of a fifty horse-power gas engine and suction gas plant driving two dynamos with a set of accumulators for the electrical lighting, and power for running the dairy and laundry plants and the electric 'incubators for hatching chickens by electricity. She has the assistance of a young lady pupil and two boys, and has set free a man who is now'engaged in making torpedoes. WIRELESS TRAIN CONTROL. Since experiments were made some two years ago on a small scale with the Prentice system of wireless train control on the "Hampton Court branch of the London and South-Western Railway, modifications have been introduced to bring it into conformity with British railway conditions, and experiments on a larger scale are now being carried out. The purpose of the apparatus is to prevent a train from running past a signal at danger, and its salient feature is that there is no mechanical connection between the track and the engine. A copper wire carrying a high frequency current runs along the line midway ' between the running rails, and is'divided into sections correspond ing with the ordinary signal sections, I the arrangement being such that when a train enters one section the current is cut off from the section immediately i behind it. The receiver on the engine consists ! of a length of copper wire directly ' over the, track wire and about 12in. ! above it. If the track wire is alive, j as it is when the section is clear, the j waves picked up from it by the receiver ' are caused to hold the brakes of the ! engine and train in the off position j and to indicate by a semaphore in the engine cab that the line is clear. But when the engine enters a. "dead" or danger section, an audible signal is sounded, the semaphore goes to danger, and the air brake is automatically applied by gravity.