Scientific and Useful.
Mataura Ensign, Volume 12, Issue 923, 25 October 1889, Page 7
Scientific and Useful.
' ', » — ■ ; A I.AND 05 GOED. The late eminent geologist, Sir Roderick Murohison, made a prediction that' is worth reviving at the present junoture. He declared from scientific data in his , possession that, in the matter of gold production, Weßtiern Australia would one day be found to be the trunk of the tree, the other great auriferous colonies — Victoria, Queensland, and New South Wales — being only the branches. And such an amount of mineral wealth has been revealed in Western Australia of late years that it would really seem as if we were within measurable distance of the full realisation of Sir [Roderick's prophecy.
A SUBTEBBAHEAN BIVBB IN K)KDON. An interesting public work at the south side of the Thames has just been interrupted by a curious obstruction. A company was recently formed, writeß a correspondent, to run a subrailway from . near London Bridge to near Olapham Common. All appears to have gone well until within 200 yards of the terminus. Here the drivers cut into a wall of gravel, and, dipping, found themselves over a subterranean river bed of distinctly aqueous character, further,- experiments led to the discovery that th'iß stream crosses the peninsula formed by the ecoentrio bed of the Thames. It is partvof the river Effta, up which good Queen Bess sailed from the Tower when she paid her visits to Sir Walter Raleigh, and it discharges still into the parent river hard by Lambeth Palace. Soundings on a cross out, with a view to a deviation in the line, were made, but though a.dip of 120 feet was made, -the ipdispensable hard foundation has not yet been discovered ; so the line s; icks. THE RADIATING POWEB OS FLAMES. At the last meeting of the Berlin Physical Society, Dr B. Von Helmholtz communicated the results of his experiments on the radiating power of flames. The problem which he had set before himself was to determine the relationship between the radiunt energy of flames and the amount of gas consumed for their production. Luminous flames radiated more energy than non-luminous, and it was proved by an extended series of careful quantitative experiments that the radiating powe* of the flames waß not dependant upon their ■ '/ ■ '
temperature. Haviig calculated the total useful effect whioh cai be obtained as radiant energy from the gasos which are consumed in the prodnotion of flane, Dr Helmholtz arrives at the interesting resilt that it is far more economical to use the Ihe gaseß for driving a dynamo which supples incandescent lamps, and to use the energy fadiated from the latter, than to burn the gasefjand to utilise the ener-, gy which is radiated oit from their non-luminous flames. j [ ■ ' ' ' SILVBRIJG IRON. ; <: A^new Austrian patented prp,oes9 for silvering articles of iron is thus described : — The article is first plunged juto a pickle of hot dil-' ute hydrochloric acid, whence ifc is removed to ,a solution of merouiy nitrate and connected with a zinc pole of i Bunsen element, gas carbon and platinum sWing'as the other pole. It 'is rapidly covered jith a layer of quicksilver, when it is removed, washed, and transferred to a silver bath and silver; 1. By heating to 3008 C. (5728 B.) the mercury is driven off and the 'silver firm!? fixed on the iron. To save silver the wire can bo first covered with a layer of tin • 1 part of cream of tartar is dissolved in 8 parts of boiling water and one or more tin anodes are joined with the carbon pole of a Bunsen element. The zinc pole communicates with a well cleaned piece of copper, and the, battery isjmade to act till enough tin has deposited on the copper, when this is taken but and the ironware put in its place. The wire thuß covered: with its tin chemically pure and silvered is much cheaper than any alvered metals. how edison's agent turned thb tables. There are sometimes amusing episodes at the President's visit to the Paris Exhibition. He is generally followed without his knowledge by newspaper men, who get money from the exhibitors by promising to speak of his ' visit. Some of the exhibitors have themselves to thank for being thus fleeced j but recently Mr Edison's agent turned the tables. After M. Oarnot had heard some passages of music by phonograph, the apparatus repeated the following message : — " A quarter of an hour ago a man styling himself reporter for the , came and said that, as the President of the Republic; was about to visit üb, he was ready for 600 f. to give us a long puff ; wheras, if we did not give him the money, he should not mention the visit. We replied that the phonograph was a scientific, not an industrial affair, and did not require puffing; but we wish to inform the President of the Republio by the phonograph of the traffic that is attempted to be made of his kind visits." M. Oarnot was much amused at this exposure, especially as the newspaper named was bit" terly anti-Republican. PAPIER-MACHE. ' The manufacture of papier-mache* (literally " chewed paper ") forms an important branch of the paper industry. Who does not remember those projectiles of our school days which we called " spit balls," and which when thrown at a wall or ceiling adhered thereto with tenacity ? What was most striking about these balls waa their extraordinary hardness after they beoame thoroughly dry, this being the more marked in proportion as the chewing had been more perfect. It was thoroughly observing such hardness that the idea occurred to' some one to employ paper pulp in the manufacture of various obj ects. Yet the subßtance employed in the industry is not " mashed " paper in the absolute sense of the word, but is a paper converted into a soft cardboard by mechanical processes. In the manufacture of papier* mache the raw material used ia a bluishgrey, unsized, strong, fine-grained paper. These sheets are. pasted together by means of a layer of dextrine or starch, applied with a steel spatula. When the desired thickness has been obtained, the mass is put into a hydraulic press that operates in a highly-heated drying-room. Under the immense pressuro of this apparatus there forms a solid block, whioh is as hard as boxwood or ebony, and which is perfectly plane or has the form of the mould in .which the raw material, so ductile when moist and so hard when dry, was compressed. It can be moulded into any shape whatever, that of table«legs, chair-3rmß, rosework, mouldings, &c. . This moulded and pressed paper can . bo easily turned in the lathe, and made into light indestructible balls and beads, or be fashioned intolinkstands, caskets, and cylinders. It is from this substance that are manufactured all those bracelets of largo black beads studded with imitation diamonds,; all those necklaces, pins, claspa, and trinklets of all sorts that are taken for jet or some precious wood. Again, those handsome bracelets composed of semi-luo d and opaline globules that seem to have been cut out of a stone formed of concentric layers, like certain precious stones, are merely of papier-maohe, cemented with white varnish, and coated with the same, : ; So, too, those beautiful nacreous, painted, and gilded trays, round tableai and oaskets. that are. known as Japanese work are' Merely' 'papier-mache. , '