THE INDIA-RUBBER AND GUTTA-PERCHA AND ELECTRICAL TRADES JOURNAL, PRICE VOL. IX., No. 8. MARCH 8, 1893. ONE SHILLING & SIXPENCE. CONTENTS. ^ PAGE PAGE PAGE The Chemistry of Gutta-Percha... 225 BANKRUPTCIES, &C 254 Carless, Capel & Leonard ...: Macalister, J. & R. viii. Liverpool Rubber Company, Applications for Letters Patent... 255 Castle Rubber Company XIX. Maclellan, George, & Co ... iii. Limited 227 EMPLOYMENT REGISTER 256 Chautard, V. & Christensen ... viii. Markus, B iv. Mandleberg v, Morley 227 Rubber Telegraphic Addresses ... xii. Clark, Sons & Co Metzeler & Co viii. The India-Rubber, Gutta-Percha, Clayton Aniline Co., Limited ... Mills, John vi. and Telegraph Works Com­ Clayton Foundry Company ... Mistovski, L., & Co xiii. pany, Limited 229 Clouth, Franz Moseley, David, & Sons ... 240 NEW INVENTIONS 230 Clyde Rubber Works Company... Nathan, M., & Co. American Rubber Notes 233 Cohen, A., & Co North British Rubber Company The Inventor of Gutta-Percha Dean & Son Peartree, A. Covered Wire 234 Delatour, Alphonse Peel Brothers & Co Boiler Explosions 235 Dermatine Company, Limited ... Powell & Barstow Submarine Telegraphy 235 Dick, R. & J Reddaway, P., & Co Horse Power 235 Employers' Liability Assurance Robinson, Jos., & Co The Waterproof Trade 236 Corporation Rowley, Thos., & Co BITS 237 Felten & Guilleaume Rubber Reclaiming Company... ELECTRICAL NOTES 238 Forster & Gregory ... ... ... Scott, G. H., & Co. New Books 239 Forster and Gregory, Limited ... Scottish India-Rubber Company LEADING ARTICLE, &C 241 ADVRTISEMKNTS. Gutta-Percha Company, The ... Shaw, Francis Vll. Dark Sayings 243 Ancoats Vale Rubber Co., Limited Heald, John Skelton, Sleat & Co XV. NOTES BY "QUIZ" 244 Anderson, Anderson, & Anderson Henley's (W. T.) Telegraph Smith, Alfred Monthly Report (La Rocque) ... 248 Anderson, Joseph & Sons Works Co., Limited 239 Sphincter Hose and Engineer­ Continental Market Report ... 249 Anderson, Wm. & Co. ... Hulme, Thomas xvii. ing Company Italian Rubber Trade 249 Armitage, Sir E., & Sons ... Hutchinson, A., & Co Thornton & Co United States Rubber Statistics 250 Armitage, Thomas xiv. Iddon Brothers Tuck & Co. ... ... ... German Rubber Trade, 1892 ... 251 Backhouse, Ambrose xiv. Irwell Rubber Company Turner Brothers XIX. The French Rubber Trade ... 252 Bender & Martiny ... ' Johnson & Phillips 256 United Asbestos Company ... 24^ The Austro-Hungarian Rubber Berthold & Co 256 Rerr & Jubb xii. Victoria Rubber Company ... Trade, 1892 253 Birnbaum, B., & Son Koeber's Ironworks Waddington & Co., Limited ... India's Rubber Trade, 1892 ... 253 Blackman Ventilating Company xviii, Kohsel & Sohn Warne, Wm., & Co Italian Sulphur Exports 253 Calmon, Alfred xiv. Kramrisch, Sgal & Co Wertheim, Louis Not So Green As He Looked ... 254 Campbell, Achnach & Co. Liverpool Rubber Company ... THE CHEMISTRY OF GUTTA-PERCHA. temperature. Towards solvents it acts in the same manner as Gutta-percha. BY GRANVILLE H. SHARPE, F.C.S., Alhine, C20H32O2, is the white crystalline solid which Lecturer on Chemistry and Technology. separates out from a hot alcoholic solution of Gutta­ (Continued from page 195.) percha, on allowing it to cool. It melts at a temperature of r75° to r8o° C.; above this point it suffers decom­ UTTA-PERCHA of commerce, besides position, and yields the same products as Gutta-percha. containing the pure hydro-carbon and Fluavile, C20H32O, is the yellow amorphous powder 6 some mechanically held water, is associated that is deposited on the alcoholic solution of Gutta­ with a considerable proportion of resinous percha cooling. Under ordinary conditions it is hard matter, as seen in the annexed analysis :— and resinous, but becomes soft when held between the Hydro-carbon .. 7970 hands, and melts between 100° and 110° C. ; if the Resin .. 1510 temperature be increased beyond this it is decomposed, Wood Fibre.. 218 Water .. 250 at the same time evolving strong smelling vapours. Ash .. 0-52 Gutta-percha in its various modifications possesses a lOOOOO remarkable porosity, as can be shewn in the following The Gutta obtained by extracting the crude article manner:—A portion is dissolved in some carbon with alcohol possesses a whitish appearance, and may disulphide, and a drop of this solution allowed to be rolled into thin sheets having a certain degree spontaneously evaporate upon a glass plate ; a thin layer of ductility, but not very elastic. When heated, of Gutta-percha is thus obtained, the porous structure it changes colour to a yellowish hue, which darkens of which may be distinctly remarked under the micro­ and becomes more transparent at an increased scope. If the spot be moistened with water, the 226 THE INDIA-RUBBER AND GUTTA-PERCHA March 8, 1893. appearance becomes more opaque, and the small sharp blades project. By a rapid rotating action the cavities are seen to be much enlarged. One of the Gutta is reduced to thin shavings, which are transferred most important properties of Gutta-percha is its power to a trough containing water, and heated by steam. of withstanding the action of most chemical substances, The water is raised to its boiling point, and the shavings and its great permanency generally. It effectually collect together in masses, which are removed for resists the action of cold water and damp, and is not further treatment to a toothed cylinder, known as a attacked by caustic soda or potash, even when in a devilling machine. In this appliance the Gutta-percha concentrated condition. Ammonia and the vegetable is reduced to fine shreds, which fall into a tank of and mineral acids do not touch it, and it remains water ; the impurities sink to the bottom, and the unaltered by contact with wines, beer, etc. purified article floats upon the surface of the water. Concentrated sulphuric acid colours it brown, These floating fragments are removed by means of emitting at the same time fumes of sulphurous acid. perforated ladles, well washed in cold water and dried. Concentrated hydrochloric acid has but a slight action It is then softened either by hot water or heated in cast- on it, and Gutta-percha tubing is consequently largely iron vessels, and finally placed in the kneading machine, employed in chemical factories for running this acid which expels a deal of water and atmospheric air, and from one vessel to another. Nitric acid, however, renders it homogeneous. This apparatus is a cylindrical exerts a powerful action upon it, evolving deep red box, inside which revolves an axis fitted with projections suffocating fumes of nitrogen oxides ; the Gutta-percha that press the Gutta against the side, and form it into a becomes pasty, and after a time dries to a friable mass. thoroughly well kneaded mass, possessing great plasti­ In the cold carbon disulphide and chloroform dissolve city, and which can be readily fashioned into any desired Gutta-percha, and the impurities may be separated shape. therefrom by filtration beneath a glass vessel, to prevent In some cases certain bodies are introduced into this loss by evaporation. The impurities remain behind masticator for the sake of adding increased hardness and upon the filter, and an almost colourless liquid passes density, or for the purpose of colouring ; amongst such through. If this solution be exposed to the atmosphere may be mentioned sulphur, yellow ochre, and vermillion, the volatile carbon disulphide will escape, and a cake of red lead, gypsum, and resin. whitish Gutta-percha will remain behind. By varying the nature and amount of the body added Raw Gutta- percha of commerce is invariably so it is easy to obtain a product of any desired condition. impure that it must pass through a preparatory cleansing Lastly, after mastication, the Gutta is once more process before it can be applied for manufacturing passed through a rolling mill and well rolled. purposes, in order to free it from the earthy and other It has at various times been proposed to substitute extraneous matters with which it is associated, and some solvent, such as carbon disulphide, for the puri­ which in many cases have been wilfully added as fication of raw Gutta-percha, in lieu of the processes adulterants. referred to, but it does not appear that hitherto the This consists at first in disintegrating the Gutta­ suggestion has met with any favourable results. percha by means of suitable machinery, and a The important property which Gutta-percha has of subsequent course of washing. It is not unfrequently resisting changes of temperature, the action of acids, the case that stones are present, which it is necessary to alkalies, and other chemicals, is considerably increased remove prior to cutting the material to pieces, so as to by treating it, under certain conditions, with sulphur avoid any damage to the machines employed. For this or some compound containing sulphur, which makes it purpose the crude blocks are softened in warm water, invaluable for many industrial purposes. and rolled out into thin sheets by means of rollers This process is known as vulcanising, and has been constructed in such a manner that if a stone appears practised for a considerable time. The sulphur is the upper roller is lifted up, and then falls down again usually incorporated in conjunction with a metal, when the stone has passed through, thus enabling a although there are various methods by which the desired workman to detach all stones effectively, and with little results can be attained, viz. :— trouble. 1. By treatment with sulphur alone, at the necessary The sheets are then folded together, so as to form a temperatures. block adapted to the size of the cutting apparatus, 2. By treatment with metallic compounds of sulphur, which is a wheel of circular construction, from which such as the sulphides of lead and antimony. March 8, 1893. 227 3. By treatment with chloride of sulphur dissolved in MANDLEBERG v. MORLEV. carbon disulphide. The following formula is given for preparing vulcanised IHE following is the judgment of Mr. Justice Gutta-percha :— • Stirling in the above case delivered in the High PARTS BY WEIGHT.