Scientific.

Waikato Times, Volume XXVI, Issue 2128, 27 February 1886, Page 2 (Supplement)

Scientific.

— STKAM FOB K\TIN(.IIHHINC FlllES.— The New York Steim Heating Company, who have. h-id their pipes laid under thw strcf ts and furnished steam for li eating and power for operating .ill kinds of machinery, iv the lower p irt of the city, are now extending their pipes further up Bro.idw.iy, and in time they expect to compass the entire city with their heiting system. The editor ot the Fireman's Journal, in a conversation some months ago with the secretary of the Steam Heating Company, was informed that before long the company would be prepared to put out fires m that portion of the city corered by their mains. Recently W. 0. Andrews, president of the company, explained definitely the plain they propose to adopt in the dry goods district for putting out fires. He said : "The use of Hto.irn for putting out fires ih not new. It is in operation in a &i'oat many factories a" over the world. There has never been any publ'c system, because tho conditions have never ex'stod before under which it could bo put i*i operation. Tno steam drives out tho air and smothers tho fi-e, and docs not damago tho goods us water does. By putting stand-pipes in each bu'lding, with 4 or 5 inch nozzles on each floor, which could be turned on from the street, tho steam could bo turned on W any part of the structure. It would be so '"'ght a draught on our boiler* that I doubt if it would lower the pressure to put out any ordinary fire. The dry goods district contains more inflammable material than any similar territory in the world. It is inadequately protected at present." This might do weU enough in coined spaces, but where the air has fu" access to the flames, firemeD are of the opinion that the fire would beat the steam every time. Still, we hope the experiment will be tiled, for it may bo made a valuable auxiliary to the fire department. — Firem in'rt Journal.

— The Standard Ohm.— Some time fiffo the International Conference of Electiicians determined to adopt the name of " ohm for the unit of electrical resistance. The vnluc of 1 ohm is represented by a mercury column of 1 metre in length, and one square metre in section, at a temperature of 0 degrees C. This resolution was taken in the spring of last year. The one th'ng that remained yet to be done was to " rea'iae" the standard ohm. Each of the different nations could undertake this real Nation. In Franrp, M. Coohory, Minister of Posts and Telesrraphs, entrusted this labour to M. Rene" Benoifc, first a-sistant-superintendent of tho International Office of Weights and Measures. M. Benoit seemed to be specially maiked out for this delicate work, seeing that he had previously prepared tho prototypes of the metre in hldiated platina, wHoh had been very much noticed M. Bfnoit, being *i advance of the scientists of other nations, lodged as early aa the sth December last, in the archives of the Ministry of Posts and Telegraphs, four standards of vex/ great accuracy, the difference bctwern them being less than 100,000 th. In this way tho standard ohm has been changed from a mere definition to a reality.

— Silicon in Cast-Iron. — In a recent paper to the Chemical Society, Mr T, Turner gave an account of some expei Iments made by t iking 1 pr v o cast-iron and fusing it with quantities of ,v':oon pig, co as to produce tost baw, which were tested by Profcbaor Kennedy, of Ui""vor.«ity College. Tho pure cist-iron was pie. pared by he.ititig wrought-iron with charcoal for about fivo hours, and the composition of the product was C=l9B, Si=ol9, Mn=ol4, P=o-32, S=o 35. Tho si'icon pig-iron wns composed of C = 1-81, Si = 9.80, Mn = 19-5, P=o/21, S = 084 The tct ban were I*l inches in diameter and 19.7 inches loner. Contrary to tho generally accepted views on the subject, a suitable addition of .silicon (up to 2"5 per cent) improves tho tensile strength of tho metal. Thus with 0 per cent, of silicon, the breaking load was 10*14 tons per f-quaro inch ; with 1 per cent it was 12.72 tons ; with 2 percent., I.WO tons ; and 25 per cent., 14 62 tons. With 3 per cent, of silicon, however, it was 12.23 ton*, and continued to full till with 5 per cent, it was 10.16 tons, aud a proportion with 10 per cent. 4.75 tons only. Silicon also gives finer, emoother cast'njrs.

— Th is Electro Deposition Alumixiom. — The use of aluminium i 3 extending from day to day, and new processes for producing it in largo quantities by electrolysis. A recent one obtains aluminium in large quantities by electrolysis. Attempts to deposit the metal in this way have frequently been made before, but with indifferent success, and the results have not been of such a nature as to promise large returns ; but Mr E. Senet, as the Bulletin Int. des Telephones reports, has devised a process for depositing aluminium as easily as copper or silver. For this purpose a current of G or seven volts and 4 amperes is employed. The electrolyte consist of a saturated solution of sulphate of aluminium in the presence of a solution of chloride of sodium (common salt), the two liquids being separated from each other by a. porous cup. By the action of the current, there is formed a double chloride of of sodium and aluminium, which is immediately decomposed, setting free the aluminium, which is deposited on the object forming the cathode. In this way an excellent deposit is obtained. —Ax Interesting Discovery. — The "Vos<:i«che Zietung " reports that quite lately, when the foundations wore being cleared for a building close to the St. Sophia Church at Kief, tho workmen oamo on some weapons, colon f od eai ..henware,' md an urn, a ll in excellent condition. The urn contained a set of ornaments for a woman in perfect preservation ; the importance of which consists lees in their antiquity (probably the tenth or eleventh rentury) thrn in their completeness. The tru was well fastened, and had evidently never been disturbed since the possessor hid away from enemios her most valuable offoots Alonar ■with other articles there wero nine old square silver coins kaown as " gilvna." Thorc is a complete head-dress, consisting of a lace- work of indescribable intricacy, but which has been kept *t» its original position by silver plates to which it is sewn, so that one can see how a well-to-do Russian woman of the preTartario times adorned himself. Tfco silver plates are oblong, su-rounding tho head and forming a sort of diadem. A quantity of silver and gold pendants hung all round from tho«e plates : the pendants which would como over the ears being much larger than tho other*. There were silver bracelets and neckluces, and a gold ring, which is not soldered, but welded, and pioba'-ily belongs even to an older dii'.e than the other objects. There was a considerable quantity of other silver and gold ornaments, chiefly pradants, many of which show extremely fine filagree work. The larger gold objects are of the cla=s known ea cloisonne work. All tho ornaments show finish and taste ; and if they are of nativo oiigin, they are e\idcDco of tho peiTection to which the art} had been brought iv Russia rae centuries ago. — Manufactorks pbom the Air.- The process of Brin Brothers is about as follows : — First, the air is drawn, by means of a partial vacuum, through a vessel of quicklime, which absorbs nil the carbonic acid and moisture, and reduces it to a mixture of o.\yg"n and nitrogen. These gasses are thou di-uvn into the retorts, heated at 500 dci{ , and the artifical lung absorbs the <>\ygeu, while the nitrogen is diawn off to a gasometer for conveisiou into ammonia, etc. The Biius have, for the first time, made the nitificial In m* indestructible. The use of b.iryta for the purpose is not unknown ; but hitherto the barty.i has been perishable, and has required renewal every four-and- twenty houis, at g.*eat expense. They make it virtually i idestructible and unchangeable. In this way they claim to have effected an absolute revolution in chemistry, for with a lung for a machine, and the atmospheric air for the material,

they ran make as much oxygen as they like, and its uses, pieaeiit find pioapeetive are almost innumerable and mc deniable. For ventilation, aerating water without carbonic acid, for increasing the heat of bh.st fnrnancps and the liyht of lamps, its uses are silf-uvident. The nitrogen, which was at fiiat looked upon ns wasted, has, by a process due to the name inventors, been turned into ammoniacnl salts for manure. Most of the U3es of these proiluots were known. What is clanu-d H tlie. almost fabulous reduction in the cost of the production. The chemical text books, according to Meiers. liiin, an; nt fault as to the possibilities of paryta. They tench that it in destructible ; and the Brins maintain that, as they know how to treat it, it is indestructible. Oxygen in large quantities means a revolution in half the processes of chemical industries. — Scientific American.