CHEMISTRY. 



113 



The Ammonium-Amalgam Controversy. 

 The American Journal of Science for May 

 contains a paper by the late Dr. 0. M. Weth- 

 erill, on the existence of the so-called com- 

 pound, ammonium-amalgam. After describing 

 the preparation of methyl-ammonium oxalate 

 by Lea's process, he says that when a portion 

 of fluid sodium amalgam, the size of a pea, was 

 placed by him in a small test-tube ( inch diam- 

 eter), and the solution of methyl-ammonium 

 oxalate was added, the swelling (or formation 

 of the mercury with the so-called metal ammo- 

 nium) was observed both with and without 

 shaking, in the cold and warm. The same ex- 

 periment was performed with different speci- 

 mens of methyl-ammonium oxalate ; in some 

 instances the swelling was from eight to ten 

 times the original volume, which was very 

 much less than the turgescence of the ammo- 

 nium salt. The methyl-ammonium amalgam 

 presented the same buttery appearance as the 

 ammonium amalgam. When the lump was 

 pressed between two plates of glass, myriads 

 of gas-bubbles were apparent ; when these 

 were pressed out, the amalgam was .at once 

 restored to the condition of mercury. A piece 

 of filter-paper was placed upon a glass plate, 

 then saturated with a strong solution of the 

 recrystallized methyl-ammonium oxalate ; a 

 globule of mercury the size of a small pea was 

 placed upon the paper with the negative poles 

 of twenty Bunsen cells in contact with it, the 

 positive pole touching the paper ; the globule 

 of mercury swelled slightly, presented a but- 

 tery appearance, attached itself to and amal- 

 gamated the blade of a penknife which was in 

 contact with the negative pole, and, upon be- 

 ing pressed under a glass plate, showed innu- 

 merable gas-bubbles in its substance in fact, 

 was a metallic froth. It results from these ex- 

 periments that the compound ammonium ex- 

 amined by this author may form the so-called 

 amalgam. 



Sulphur in Illuminating Gas. The follow- 

 ing practical method of proving the presence 

 of sulphur in illuminating gas is published by 

 Ulex, of Hamburg. 



If a platinum dish is filled with half a litre of water 

 and heated over a Bunsen burner until all the water 

 is evaporated, a viscous fluid is found on the outside 

 of the dish, where it was in contact with the flame, 

 which is concentrated sulphuric acid. A second 

 proof of the presence of sulphur in purified coal-gas 

 can be obtained from lamp-chimneys. After being 

 used a short time, their interior becomes lined with 

 a white coating, and in places with incrustations. If 

 they are rinsed out with water, sulphate of ammonia 

 is found in this. A more convincing proof is the 

 following : If several gas-burners have been ignited 

 in a room for several evenings, it is only necessary 

 to rub the tip of the finger over a pane of glass and 

 wash it oft* with distilled water, to obtain a solu- 

 tion, which turns white and milky, on the addition 

 of barium chloride, from sulphate of "baryta, and 

 brick-red on the addition of iodide of potassium 

 and mercury. If the windows of a room in which 

 gas is burnt are not washed for a week, thousands 

 of small lustrous crystals may be observed in sun- 

 light, which also give the above reaction, and prove 

 to be sulphate of ammonia, and, as the solution has 

 VOL. xi. 8 A 



an acid reaction, contain an excess of sulphuric acid. 

 To the presence of sulphate-of-ammonia fumes in a 

 room must probably be ascribed the difficulty with 

 which plants are raised in the same, and often die, 

 and the complaint of persons with weak lungs of the 

 dryness of the air in rooms where gas is burned, 

 while in reality the moisture of the same is so much 

 increased by burning-gas. 



Chemistry of Tobacco - Smoke. Drs. Yohl 

 and Eulenberg have invariably found nicotine 

 in commercial smoking-tobacco four per cent. 

 or more while only traces of it could be dis- 

 covered in chewing- tobacco and snuff. They 

 say that there are no cases on record of nico- 

 tine-poisoning from the use of snuffor chewing- 

 tobacco. The gaseous products of the combus- 

 tion of good cigars and smoking-tobacco are 

 oxygen, nitrogen, marsh-gas, carbonic oxide, 

 sulphuretted hydrogen, and hydrocyanic acid. 

 Other products are formic, acetic, metacetic, 

 butyric, valeric, and carbolic acids; creosote 

 and succinic acid, a solid hydro-carbon and a 

 liquid hydro-carbon. The poisonous charac- 

 teristics of tobacco are found in the alkaloids 

 of the pyridin and picolin series, produced 

 from the destructive distillation of wood as 

 well as from tobacco. . Experiments upon ani- 

 mals proved that these were sufficient to cause 

 death. The same alkaloids resulting from the 

 distillation of opium, Drs. Vohl and Eulenberg 

 suggest that those substances, and not the mor- 

 phine, cause the effects noticeable in opium- 

 smoking. 



Chinese Varnish. The Chinese varnish, 

 schio-lias, employed for making wooden ves- 

 sels water-tight, is said to be made by mixing 

 three parts of fresh-beaten, defibrinated blood 

 with four parts of slacked lime and some alum 

 the result being a thin, sticky mass, which is 

 immediately ready for use. Wooden chests 

 coated two or three times with this varnish 

 have performed the journey over Siberia to St. 

 Petersburg and back, and remained sound 

 and water-tight. Even baskets of straw, used 

 in China for the transportation of oil, are made 

 perfectly fit for the purpose. Pasteboard by 

 its use becomes both in appearance and firm- 

 ness like wood. In China most of the ex- 

 posed wood-work is coated with schio-lias, 

 which gives it an ugly red appearance, but it 

 gains in durability. - 



Etching on Glass. In place of using aqueous 

 hydrofluoric acid for engraving on glass, Mr. 

 Siegevart recommends a solution of eight parts 

 of any alkaline fluoride dissolved in 100 parts 

 of water, mixing this solution, just previous to 

 use, with one part of oil of vitriol. In order 

 to remove any trace of organic matter, the 

 glass before immersion in the bath should be 

 thoroughly cleansed with a solution of bichro- 

 mate of potash, acidulated with sulphuric acid. 

 A few hours' exposure is said to be sufficient 

 at ordinary temperatures to obtain a true frost- 

 ed surface. 



Chloralum. This article, the accurate chem- 

 ical term for which is chloride of aluminium, 

 is coming into use in England as a disinfectant,, 



