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Show SCIENTIFIC LETTER. With the Metals The Body Will Burn -Notes. Experiments With UeUU-An in tor-eating tor-eating series of nw alloys of gold willi aluminum was shown by Professor Roberts-Austen in a lecture at the Loudon Lou-don Ryal institution a few days ago. One of these, containing 20 per cent of aluminum, Is esrecially remarkable as forming an exception to the usual rule that the melting point of an alloy is lower than that of either of it! constituents, constitu-ents, this alloy having a melting point above that of gold, its tuoit infusible element. Very curiously, the alloy with 10 per cent of aluminum follows the usual role. These alloys, it may be added, have very brilliant colors, the 20 per cent alloy beiiig a beautiful ruby, while those containing greater percentages percent-ages of aluminum are purple. In determining the fusing points of the most refractory motale, Professor Riberts Austen used as pyrometer a thermo-couple consisting of a rod of an alloy of the same metal with 10 per cent of platinum. With this instrument instru-ment he has measured temperatures as high as 2000 centigrade, and it is now possible lo make measurements ranging rang-ing from that temperature down to 2000 below zsro. By means of an oxy-hydro-gen blowpipe and a reflecting galvanometer galvano-meter the lecturer was able to show the recalescence o! iroD, and that at this point the iron becomes sndlenly magnetic. mag-netic. An experiment of greater prac tical interest was that of cooling a load, d red hot bar of iron which remained re-mained rigid nntil it reached its point of recalescence, when it suddenly began to bend. Street Microbes The dust of the streets ot Naples has been t e snbject of an elsbrate investigation by Dr. Luigi Maufredi, who reveals startling possi bilitks of evil. The microbes of all kind found in the dust averaged 716,-521X00 716,-521X00 per gramme, though in the cleanest and least traveled streets! the average number was only 10,000,000 per gramme, while in tte bnsiest thoroughfare thorough-fare it rose to l,O00,OC0,C0O, and inionie uf ihe dirtiest streets to the enormous figure of .5,000,000.000 per gramme. witnessed by the medical attendant has been lately des iibed by Dr. B. II-llartwell II-llartwell of Ayer Mass. On May 21, ISM, this physician was hastily summoned sum-moned into a garden near which lie happened to be, and there he found a burning woman lying on the ground the Hames reaching to a height of 12 or 15 inches above the bo.ly. On smothering smother-ing the fire, it was seen that the flesh of the right shoulder, the abdomen and both legs had burned and the bones of the legs had been calcined. The woman was 49 years old, of active and nervons temperament, and, nnlike most persons alleged to' have burned, was not very fat, and was not addicted to the use of alcohol. Fire hal caught in her clothing cloth-ing from a pile of roots she had been destroying. Proof that the flesh was set on fire by the clothing alone, and burned of Itself, was the fact that only a few charred leaves were aronnd or under tho body. The longest cataleptic sleep knofii to medical science has been attracting attention in Germany. The latest report states that the man a miner of Silesia had been unconscious for four and a half months, with no unnatural appearance except absolute rigidity of the limbs. During this time the patient's pa-tient's hair has grown but his beard has remained stationary. Food is given by tube. Pipes of cement in which wire net ting is imbedded are now being made, in Berlin. The wire netting increases the strength of the pipes, and adapts them for service as waier conduits. On a French railway requiring no locomotive in one direction, on account of being all down grade, it is proposed to nse eleotric motors, and to make the descending train generate and btore part of the current necessary for returning. return-ing. The German public has been warned against certain forms of stoves, from whose nse several cases of poisoning by carbonic cxid are known, to have resulted. re-sulted. The black metallic sand covering the bottom of the bay of San Blas.Argentine Republic, proves to be very rich in iilver. Many of these organisms were those of disease, and the nnhealthinoes of the street or qaarter was directly proportional propor-tional to the number of microbes in the dust. The infective power of the dnst was tested with positive results in 73 pircent of the experiment -suppuration, tetanus, tuberculocin. blood-poisot'l blood-poisot'l g, etc., te'Dgprcdue d in du-st inoculated guinea-pigs. The New Jiurypls cf Electiicity Mr. Tesla, the American electrician whose brilliant experiments have been excit ing the world's wonder, believes thut all substances may ba madeplio?p',oiescent by electric currents of sufficiently rapid oscillation and hih pressure. What i-ncces6arj i-ncces6arj is to drive the air molecules forcibly enough and nnmeronsiy enough more forcibly aod nnmeroHsIy in open air than in a patt;al vacuum-to vacuum-to raiso the surface of the substance to the glowing stage. In his late expert menls before the London institution o! eh ctrical engineers, Mr. Tesla used a special alternating c rrent dynamo, with 3S0 electro-magnets, driven at a speed cf 2000 revolutions per minute, and supplying a current oscillating 13.0CO times per second. Passing through a battery of leyden jars nnd the primary circuit of an induction coil, currents from this machine were given a frequency of one or two million times per second, and enormsusly high potential. poten-tial. Between two sheets of tin foil connected with the poles of this generator gener-ator and placed several feet apart, the npace was endowed with most extraordinary extraordi-nary properties. An exhausted tube waved in it, though having no electrical electri-cal connection, glowed like a flaming sword, and a glow lamp held in it gave oat light. Connected with one pole of ihe generator, a metal oint shone in the dark like a torch, and two parallel wires about a foot apart, each connected with one pole, glowed with a blue light throughout their length while a sheet of flame, burning without consumption of material except the current, showed between the wires. This flame is explained ex-plained as being due to collisions of the air molecules. Most singularly the highly electrified atmosphei e is utterly without effect on the human body, and it mny become practicable to electrify whole rooms sufficiently to cause glow lamps in them to give light, or even to make the atmosphere Inminous. A Dim "Central Sun"-Not long ago Professor Vogel showed that the variability varia-bility of the star Algol is due to the regular passage before it, in periods of about sixty-nine hours, of a dark body which cnts off a portion of the light. Mr. S. C. Chandlers has now deman-strated deman-strated mathematically tint Algol and its dark satellite are moving around another dark or feebly illuminated body so distant that the revolution requires about 130 year?. Confirmation of this discovery will have an especial interest, as tending to prove the existence of large daik bodies throughout spac- Will the Body Burn? Over seventy cases of so-called sponraneous combustion com-bustion of the human body are recorded in medical literature, and seem to show that the living body, under certain conditions, con-ditions, must at least support combustion. com-bustion. The first case, however, in which the burning has been actually |