Arizona republican., 1901-10-27
SCIENTIFIC MISCELLANY

eilli of the Baltic sea have been a sub ject of study by Nj. T. Tarchanoff. The light is found to be a manifestation of respiration. connected with the con sumption of oxygen. and the power Of emitting 1t lasts for two or three weeks to as many months. Shocks and the introduction of air excite extra activ- ity. The luminosity Is affected also by chemicals and by temperature. being temporarily extinguished at about :is degrees C. and permanently so at 30 degrees. but continuing considerably below freezing point. The pressure of the bacilli. therefore, may give for sev- eral hours the remarkable phenomenon of luminous ice. Even more striking r. the luminous frog. which NJ. Tarcha- noff produced by injecting a little Q: the bouillon into the dorsal lymphat!c sac of the frog. when the bacilli entered the blood and gradually illuminated tn. whole animal. the tongue shining with great brillianoy. This strange effect. lasted three or four hours.
 Much as it has been sought. a sat- isfactory solder for aluminium is re- ported to be still wanting. The diffi- culties are due to the rapid cooling of the joint through the high heat con ductiyity of aluminium. and to corro- sion by galvanic action between the aluminium and the metals of the solder. Mixtures of zinc and tin that appear to adhere firmly are loosened after few months by this corrosion. Heating the joint during soldering may overcome one difficulty. but solder containing sufficient aluminium to prevent gal vanic action cannot be melted with the soldering iron.
 
 In the new method of steamboat pro- pulsion of MT. Robert Carr. steam IS generated in special boiler. and Is made to drive air through tubes open ing at the stern, the pressure of the ais against the water driving the boat. Reversing is effected by turning the ai- into a tube running to the bow. ant steering by closing the jet on one side.
 The difficult ptroblem of getting in fantry across streams is solved by Commander Cluchagne. of the French army, in very simple manner H. employs easily carried metal cylinders twelve inches long and six inches il diameter, which may be divided into halves for use as pails and kettI.s during halt. and which may be closed to serve as water-tight buoys, with special couplings to attach them 1 pairs to swimming belts or to join them fin considerable number for rafts and bridges. The pair of buoys beltei to the pack not only floats the non- swimmer. but is a very effective aid in learning the art of swimming For crossing wide rivers a raft ten feet long. composed of 16O cylinders, has been used. and this readily carried six men. forty-six knapsacks and four guns. total weight of 1880 pounds. Bridges are readily pushed across mar row streams. a bridge forty feet long and three feet wide formed of 24O cyl finders. weighing 4s5 pounds.
 
 Important advantages are claimed for the new process of diluting acety- lene by passing it through a volatile hydrocarbon, like petroleum. ether or gasoline. with exclusion of air. The gas thus carbureted seems to overcome the difficulties of acetylene incandes- cent lighting. as 1t heats the mantle without depositing soot and does not show the tendency of pure acetylene to recoil into the burner. while 1t gives much cheaper illumination than any other acetylene light. The explosive ness of the acetylene is materially less ened. while it Is made more availabl for use in gas engines.
 
 The species of fungi that have been known to show luminosity are found by Prof. D. McAlpine to number twenty-one. of which eleven belong to the genus Pleurotus. and five are pecu- liar to Australia. The luminosity is not due to phosphorescent bacteria. but to eombustion-probably of excreted metabolic products-in the fungus it. self The light is thought to serve the fungus by attracting insects that scat ter its spores.
 An atmospheric" or Newcomer en- zine near Glasgow has been lifting coal since 1909. It has cylinder 32A inches in diameter and 66 inch stroke. and is run at twenty-seven revolutions per minute, with a pressure of 7h pounds. developing twenty-seven horse power.
 The rapid decay of leather. which is becoming painfully noticeable where ever this material Is used. Is traced bv a committee of British librarians to the quick processes of modern tanners. The use of certain mineral acids is con demned. as we'll excessive shaving. ernbossing and glazing: and the catechol series of tanning agents which includes gambler, larch. uuel- bracho, hemlock and turwar bark-:s found to produce leather that is very liable to rot quickly. Leather so tanned is much used for cheap book binding. Much more durable proves to be leather made with the pyrogallol class of tannin. including myrabolas and sumac; and pure sumac is recom- mended as the best tanning material for bookbinding leather.
 The demonstration of the earth's curvature by leveling has been lately repeated by MT. H. Yule Oldham with q view of obtaining a photographic record. On a straight stretch of the English river Bedford are two bridges, six miles apart, with no intervening obstacles. and the height above water level of the parapet of one bridge was