NOTES ON SCIENCE, MECHANICAL INVENTIONS ETC.

New Zealand Herald, Volume XXVI, Issue 9325, 30 March 1889, Page 4 (Supplement)

NOTES ON SCIENCE, MECHANICAL INVENTIONS ETC.

' THE AGE OF,. TREES. , [ Where - "the zone test can be applied, Wo ' • knoxVlihat the ago 'imputed to th& tree will /■hot err* in the way of excess, clearly marked;'ij'ing Seasons growth. "season to" have resulted in an - unusually f thin or perhaps 'ah indistinguishable' lay&, .ono year's credit will remain unentered*in tho tree's automatic "On this basis 'of computation the following ages have been strictly " verified „in Germany. In ''that country, as in Finland and ' Sweden, the * pi no and fir have attayicd td from <)QQ;,to ,700 years. The greatest ascertained' age of the larch (in Bavaria) is 274 years/ while tho fjtlver fir has reached 248. Tho oldest known specimen oft tho iiolm oak (near Achaflenburg) t numbered 4TO years ;jvyhilo in all the common oaks aboufffeO years old the . heart was beginning .to decay. Tho maximum ages of other Gorman trees—as found by counting tho>»rings— aro as follows:—Red beech;. 245 ; 'ash, 170"; elm, 130 ; birch, 200;»aspen, 210; and alder, 145 years. Tho*' lime, beloved gf tho Fatherland, generally evades ■ this test. Probably one of tjhe longest standing of all, it is seldom found in a sound condition* at an advanced age. • . # MOUNTAINS OF IRON. . _ , , Mountains- of iron aro becoming quite common. in various parts' of the world. The latest discovery..ofthis kii^di.has,ro cently been found in Burmah. . Dr. Noetling, of the Geological Survey of India,- in a recent report ..on magnetic .rock: among tho Shan' Hills of Upper Burmah, describes a mountain or lii if at Suigauiig " consists of a lingo mass o£ iron ore/-. Having, lie says, , noticed on the, "way numerous pieces of iron ore, which became stilljnoro frequent on thd* southern rftde of: the hill, fie examined the latter in several directiShs. lie found tho, surface everywhere covered'with largo blocks of.iton ore, originating evidently from superficial decomposition of lower beds; .He concluded, "that the whole hill consisted of a largo'mass of iron ore. Ho was unable to ascertain the geological conditions under which this ore occurs, or its exact limits and extensions, on account of the dense jungle and the tremendous- attraction rendering his compass useless. He estimates, however, tjhat tho hill covers, abreast, an area of about';; square mile, and that it rises abous 200 feet above the level of tho Twiungo valley. The oro is liematito peroxide" of iron.' .. LIGHTING DOMESTIC FIRES BY ELECTRICITY. Mr.'Leigh S. Powell, in the columns of Jthe Electrical Review, "suggests a new use 'for electricity, i.e., to light domestic fires. He proposes to make the bars of the grate one electrode, anil an iron plabe lob into the back part of tho grate the other. Cinders and colte being themselves conductors, when the 'grate is filled with these and the current turned on, heat is developed at tho points of contact between tho pieces of fuel, these localities being those of tho highest resistance. With an experimental arrangement Mr. Powell found tho cost of lighting a fire to be l ; , J d or 2d—a prohibitive price—but ho thinks that with a greater E. M. F. than he had at command this cost would be* much reduced. Breams of being able to light a tire by pressing a button before you get out of bed on a cold winter morning are undoubtedly..pleasant. FELLING TREES BY ELECTRICITY. • Hitherto machines for felling trees have been driven by steam power, but this is sometimes inconvenient, especially in thick woods, and electric power has recently been adopted in the Galician forests. Usually, in such machines, tho trunk is sawn, but its this case it is drilled. When tho wood is of a soft nature the drill has a sweeping motion, and cuts into the trunk by means of cutting edges on its sides. The drill is actuated by, an electric motor mounted on a carriage/ which is brought up close to the tree and shackled to it. Tho motor is capable of turning round its vertical axis ; and the drill is geared to it in such a manner that it can turn through an arc of a circle and make a sweeping cut 'into the trunk. The first cut made, tho drill is advanced a few notches, and another section of tho wood removed 4 in the same way, until the trunk is half severed. It is then clamped to keep the cut from closing, and the operation continued until it would bo unsafe to go on. The remainder is finished by a handsaw or .an, axe. The current is conveyed .to tho."motor by in-*, sulatcd leads brought Vthrough tho forest from a generator placed in some convenient site. ■ : ' REVOLUTION GAS. BURNINO. A revolution in, gas ; burning, says the* New York Tribune, is proposed by Charles S. Upton, manager of the Rochester Lamp Company, New York City, who has patented,; at a cost of £10,000, in ;all countries in-'the. 'world, a new gas-burner; •.•The " ISiagara"! burner, as it is termed, sheds; a soft'lamp-! {light of • 100-candle power, consumes "six 1 feet of gas an hour, is simple in construction, and will-, be made to fit any gas The secret of the patent is in sub.emitting' the-flame ; tp ; a -process of combustion, through perforated .brass fittings after ltlleaves the jet. , One hundred,men are at present',employed making;-a.stock of tho nevr\burners,*whioli will be on'salo soon at the price :of6s each. ...j' ; Hits'; i .-

PERMANENT- FOUNDATIONS. - «'One of the troublesome which architects have never rbcen*able to'settle is .tlfo '•-placing : of permanent -' foundations under large" buildings. -The" very latest experiment tried, according-to tho. "'American Architectj is* to cover— commencing 'tire 'footingtlie entiro area of ; the excavation of the building with a thick stratum of concrete, laid directly upon the top of the clay' hard-pan. The depth of this course is nearly two feet, and its object is to strengthen the clay, that tho settlement may bo-reduced to a minimum. MISCELLANEOUS.

Two electric lifts will bo employed in connection with the Eiffel Tower in the forthcoming Paris Exhibition. They will convey,.the public from the second to the f third, floor .of the tower, a distance of 492 -feet, and will make the trip in five minutes ■, and 'J without any intermediate* stoppage.;* The car of each lift will accommodate. 100 persons. Within a radius of 40 miles of Rochester, New York, thero are more than 1500 fruit evaporators,' giving employment during the autumn and winter to about 30,000 hands. Last season the production of these evaporators was about 30,000,000 pounds, worth at first cost about £400,000. A large proportion of the product is exported. A novelty for children in the form of a skinping-rppe which "plays tunes while it ' 1SC( 1 has been'introduced. ' There ls ; a > s'inall musical box fixed at the end of ( one' of the handles of the rope, and' the ', turning of the rope puts it at onco in action. I

Colorado is becoming an oil-producing state. In the Valley of tho Arkansas, near Pueblo, thero are a numbor of wells the yield of which is 1000 barrels per day. . Thero are several effectual means of taking." out grease spots. Chloroform will do . it. • So will a mixture of ; alcohol and ammonia ; or you can', wot tho place with•ammonia; water ; " then lay a white soft paper over it, and iron with a hot iron. Or rub French chalk on the wrong side ; lot it remain a day, split , a visiting card, lay the rough .side on the spot, and pass a warm iron lightly over. Or try the old-fashioned "grease bills"— stiff paste made of fuller's .earth and vinegar, moulded into balls and dried, wet the spot, scrape the ball over it, let it dry, and then wash it off with tepid ,watc/. ' :

ts' An .electric magnet with a carrying capacity of "800, pounds is attached to a crane in the Cleveland, O;, steel works, and readily picksilUp:.and handles billets and other masses., of iron without ; the use of chains, tongs," or : other devices. A mere lad is .thus enabled to do the work of 14 or 15 men. J ; . # According to the Mail and 'Express, quoted .by the Scientific American';, Mr. " 'AJ}ram'\Clark claims that he is ■ able, to make a lens 5 feet in diameter —" onawhich will bring'the moon within a few thousand feet of'.tho earth."

COal loses from 10 to 40 per cent, of its evaporative power if exposed to the effeots of sunshine and rain.

Robert Stevenson,; engineer, of Glasgow, is the last one to claim 'an invention which will drive ocean ships up to forty knots *an hour. : * , •' ■

It is stated thafc;a ; workman in the.Carson, Nevada,-mint has made 'the discovery that drill points-may be so tempered electrically that bhey, will penetrate the hardest steel or plate glass by being; Heated to a cherry red and then driven into a piece of lead.