SCIENCE NOTES.

Woodville Examiner, Volume V, Issue 45, 3 April 1889, Page 2

SCIENCE NOTES.

..A MECHANWAL NpVgl/JY,; ; ; y, \ ■ The- remarkable 'Mannesman.'! process ot making seamless tubes is described by-Mr F. Siemens as consisting in passing tin? red-hot bar of solid metal hrg'.'assbßtween; reyolving-cqnpidicalrolls... T^ascrolls are so arranged that the vary tut? velocities of revolution with which the'different parts are-brought into contact cause the formation of a hollow through the bar’s centre. Tubes a fool/ in diameter, witlTa/shdllonly a quarter of an inch thick, may be produced iii this way, ana great strength is chrimettfortlieTn7" Tubes with sealed ends jn;ty lie made, the hollow centre being a vacuum? o , , •

AGES.: , : ' ’An ufferasimg feißdre of the Paris Exhibition wifi be, a group of forty-pine struc; lures' iofeh led to.gixe a history of the ham.ui dwelling. The different types of shelter represented Will include-those of. the ' prehistoric' period-under rocks, in caves, on water and on land ; and .from, later tunes those of early historic civilization, of Aryan civilization, of Roman civilization in the East and in the WhSt/aifd of rude civilizations disconnected from the general progress ofhumanity-the Chinese, Japanese,-, Eskimo,' -’African, Aztec;-fete.. Fhe iiipoi:lpr3 t 'tlie,'costaiiies- of the oec.u-:, (jiuits, ami the surroundings will be those of the different epochs studied. THS-ELECTRIC AGE. • ‘ v / that elec- . tHcal sciepoe has-Jaadiß a greater, advance; in the last twenty years than in all the 600- liistoflb years preceeding.: / Mere* is discovered in one day now than 1000 years of the middle ages. We find alt sorts'oT'Tvbrk for eletrieitv. to' do. 'We oiakp it - carry opr messages, ''drive bar-' engines,, ring our door-belly'.and scare; the burglar; we-take itits'a mwli.cmC/Hght,' our gas with it, see by it, heay from talk with it, and now-we are beginning to teachit to write.

; onb:year clocks.-,. - ■ , An important improvement in clocks,has, keen shown the 'British Association for the advancement' of science by.TMt .W;. H. Douglas. ■ The new feature is the torsion pendulum,' which, with lever and escapement, may be applied•,to prdipacj works-, and by its slow rate of,vibration makes practicable the con version of'aheigh t-day clookirito one requiring winding only'once a year. . ' ■, ' PHOTbfiRAhHIC PIiOGKESS. ■/ .' . Among recent -camera achievements' is a portrait copy'taken by the light of a Cuban fire-fly in thirty seconds," aml'a ; photograph .of (he. aurora borealis. To obtain the latter had.'been'declared ah utter impossibility. .m.... ; i