| Show SCIENTIFIC MISCEllANY The e Ilea idea that the critical temperature for tempering steel Is the temperature at the motel loses hoses Ia Its magnetic pro properties has suggested to Wilam William r lor br I a a ulous In for tor guiding tempering work log Ing his theory by experiments with an electrical balance he made for br factory work on nn Instrument ot of a per permanent manent hor horse e shoe magnet having extend extended r ed cd soft ot Irn iron Iles poles one pale being ann arrn ge geto 11 to 10 rock back under normal condit I A Apiece Apiece piece of at cold steel holds both lot so op but when the 1 ample Is 11 II UI Is its magnetic properties are lot lost th the rocking in 19 released ed and Is Its dying back gives time tho signal for tor Quenching the tho steel ro The device has baa proven ot of great grent value lue In avoiding overheatIng wih with the ing resulting brittleness cracking and warp Building engineering structures on a toilet old foundation of at water Is ii the rather rathel startling plan b by which W tv E B Murray 1 a California engIneer to confer upon the world The Tho float noat In log would have 1 a large weight weighted el ed bUO bare with n a brad broad projecting flange nanga an and would be Immert immersed 1 In th the sea the Iho tower lower portion would rest In the tho waters belo below the disturbed surface With Wih form torm or of construction it II Is believed that th action of ae waves would olid b be slight I It I is that Ihl this form torm ot of building should have a wide range oC f u usefulness and I IL Is specIally adapted for tire lighthouses Cors forts and bridges When tell signals are souL under to mc 11 vessel e Lr Lord Rayleigh has haB fecund the microphone receiver wi will lp whether tho sound e from the right or orthe orth the th left leCt but bue that I it cannot be determined wih with certainty whether tue tho signals la is from a point ahead or one behind n attempt to trace trace th the origin of oC zoological gardens and natural history museums hn has been made by J von Pley Pleyel el ei i a German lie Ho concludes that genes gerles originated parly partly In the war worship hip of sacred and tarl partly In the ambi lon lion of rulers to collect specimens ot of rare valuable and laRe savage creature creatures Te simplest form torm of zoological gardens was known to the Chinese Greeks Greek wa Homan and Mexicans In Iner er ery ancient times a Chinese menagerie dating front lW I ii C being the oldest on record The Tho don den or of lons lions kept by of which we lo are told lold In the Iho nook Book ot of Daniel Is ni an ot of Ihl the prim primtivo tivo menageries and the Iho sacred acred white hrc horses ot of and nOI and tho th s eQ railed white ot of Burma nUrma and SIam tilam represent another typo The mona menA gori In In Park London seems aroma to ha have ve suggested te the u es In Paris Faris that Is regarded as the Iho modern zoological garden a Groping In or dim light the tho diver has beep been ablo abie hitherto to make only the simplest makeshIft repairs but wit the Yale submarine lamp Ind and recently In pneumatic tools It is 18 possible for him 11 to 10 do almot alY ny and clean Ing tag ot of ut docking The lamp 8 a watertIght metallic casing enclosIng a a special t double siaM glass chamber beneath the tho casing I Is pro pra by a a rIgid metal guard anI and holds tho carbons A storage bater battery or small generator supplies electric curent current through f a suitable cable The submerged lamp weighing but I a tow pounds 11 nutty be easily carried about anti lights a equal tl to larer rom romA room A novel 10 die made by a firm hB has semicircular te teeth lh which haive th con convex vex fX Ilde chic toward the point ot of tIme tile tilean an are cut very cry deep The Thos ne tile II Ic adapt nl ted led Cor or hat soft metals wood od And marble anti II is claimed to 10 d do three times tim the work ot of the ordinary nil file while keep Ing Is its edge edgo longer being and cutting without slipping A nw new at Brussels II is to he be bemid mid matte on institution vt of Import flare and In place ot of the fhe usual few Cew tank ot of more or less fishes It Is expected to display the tho complete l le river lake laka rind pond fauna tRUM of Ie Belgium um Mona to than this nn a as much or of the o nora flora wi will he ba shown ns as II city be found proc The central salon alon will resemble wi a winter garden Hh I ft central basin buln send and tanks let Into time Iho wals wails end some ome tanks vil chew specimens of oC al alt nouN while others wIll contain crustaceans wi tans reptiles orm I insects ard and plank ton ton To old In r thin the net list gina Inn rivers wIth natIve md tren fishes viii 1 he n ii of nf the directors F pedal attention wll 11 bo be given lu to foreign s c ant and one coo tank I to 10 b be reserved for the IlIa American catfish which h i to 10 b be Into the riven or th the country 1 Clari reinforced th wire has be been n shown hown b by tIe 1 rf f Ih the fire pI pra 1101 committee to fo b be realy really of great I advantage In r tI 1 tire Tree Tiree ope open Ings wert cere wih lh wired Ilau glass fire was R for It H I Iho th tern tem hAl 1 F but butot not ot I t I degrees The e new mi ma Is Io nt not only tom tor Ih the oh Db I effer to 10 tre nrc but for tor 11 Its reo me to 10 do ty by breakIng mall Ind and felling whOn In such II as the tho glass rr roofs ot of stations |
