CHEMISTRY. 



119 



oil, and heavy oil and paraffin. The heavy oil and 

 parafiin are frozen and pressed. Solid parallin 

 (known as "scale" when in the crude state) is left 

 in the filter presses, while blue oil passes through. 

 The lattec undergoes further treatment with acid 

 and soda, and is fractionated into gas and lubricat- 

 ing oils. The lubricating oils are displacing vege- 

 table oils for machinery, since they do not clog and 

 are not liable to spontaneous combustion. The 

 paraffin scale, after further pressing, is purified by 

 sweating " out the oil and coloring matters, and 

 is then washed with bone black, filtered, and run 

 into cakes. It was pointed out in the discussion of 

 Mr. Kerr's paper that when stearine is added to the 

 wax in candle making, although the wax is made 

 harder, the melting point is lowered. 



In a process by M. Piloty to obtain anhydrous 

 hyponitrous acid, silver hyponitrite, suspended in 

 ether and treated with hydrogen chloride, gives 

 silver chloride and a solution of H 2 X 2 Oa in ether. 

 Kapid evaporation of the ether causes the deposition 

 of the acid as an oil, which solidifies in a freezing 

 mixture to a crystalline mass. Both the oil and 

 the solid possess explosive qualities. Of the nu- 

 merous isomerides of the formula HaXaOj theoret- 

 ically possible, this is the second to be isolated, the 

 nitraraide NHNO of Thiele and Lachman being 

 the first. 



In the same author's method of preparing the 

 salts of hyponitrous acid, hydroxylamine hydro- 

 chloride, by treatment in alcholic solution with 

 sodium ethylate and benzene-sulphonic chloride, is 

 cultivated into benzene sulphone-hydroxylamine, 

 C 6 H 5 S03.NH.OH. and this on treatment with con- 

 centrated-potash solution, gives the potassium salts 

 of benzene-sulphonic and hyponitrous acids, which 

 can be separated without difficulty. The mechanism 

 of the reaction is analogous to the production of 

 hyponitrite from potassium hydroxylamine mono- 

 sulphate. 



The process for the electrolytic production of 

 chlorate of potash, recently instituted by a manu- 

 facturing company at Niagara Falls, consists in 

 dissolving nitrate of potash (or chloride of potassium) 

 in tanks and filtering; then running the solution 

 into porcelain-lined pots, where it is decomposed, 

 forming the chlorate. This is allowed to run down 

 into crystallizing pans, after which it is freed from 

 moisture in centrifugal driers, dried in drying rooms, 

 and then packed. The operation, from the time 

 the muriate solution enters the hot room to the 

 time the chlorate is ready for shipment, consumes 

 about twenty-four hours. 



H. X. Warren has successfully used the principle 

 of electro-dissolution in the separation of boron, 

 silicon, and phosphorus from iron, the results seem- 

 ing to be most satisfactory with the boron. He has 

 also separated copper from its impurities of iron, 

 zinc, arsenic, etc., using hydrochloric acid as a sol- 

 vent instead of sulphuric acid. He has used this 

 method with excellent results in the analysis of com- 

 mercial copper, and has been able to detect arsenic in 

 it when all other methods failed. Electro-dissolution 

 may also be employed in the preparation of unstable 

 compounds, such as stannic nitrate, potassic ferrate, 

 ferric aceta'.e. which are decomposed on the appli- 

 cation of heat. 



Many properties of tellurium are described by 

 Cabell Whitehead in a paper on its separation from 

 copper residues. In the electrical refining of cop- 

 per ores, the washings from the gold residue con- 

 tain it as tellurous oxide or sulphate. It may be 

 obtained from these either by precipitation with 

 copper or by passing sulphurous anhydride through 

 the solution, and may be finally purified by distilla- 

 tion in hydrogen. When a solution of sodium tellu- 

 rite is added to a solution of an ammonium salt, a 



precipitated by sulphurous anhydride remains in >< 

 lution. Potassium ferrocvanide does not react wit 



white precipitate of tellurous anhydride is thrown 

 down, which becomes granular on boiling. A small 

 amount of tellurium or of some metal which can be- 

 not react with 

 tellurium chloride at once, but after a few hours 

 Prussian blue is formed. When tellurium is heated 

 with aluminium, the two combine with explosive 

 violence, forming a chololate-colored compound 

 difficult of fusion, which has the composition Al s Tej. 

 It is hard arid brittle, and can be readily ground to 

 powder ; when exposed to moist air it is decomposed, 

 and hydrogen telluride is slowly evolved ; when 

 thrown into water it is rapidly decomposed. Tellu- 

 rium is readily deposited by an electric current 

 from either an acid or an alkaline solution. It has 

 been found possible to separate tell urium from copper 

 by adding an excess of sodium hydroxide and about 

 3 grammes of potassium cyanide for each gramme of 

 copper present, and passing an electric current 

 through the solution, when the tellurium is thrown 

 down as a black, nonadherent precipitate which 

 can be readily filtered off. The solution can then 

 be slightly acidified with sulphuric acid, and the 

 copper estimated in the usual way by electrolysis. 



M. P. Pictet's method for the rapid determination 

 of nitric nitrogen in vegetable products depends on 

 the coloration taken by brucine on contact with 

 nitric acid, free or liberated from a nitrate by the 

 action of concentrated sulphuric acid. A drop of 

 the liquid containing the nitrate is placed on a plate 

 of porcelain, and a drop of pure concentrated sul- 

 phuric acid is mixed with it. Some . fragments of 

 brucine are allowed to fall into the liquid, which is 

 successively diluted with distilled water, the dilu- 

 tion being increased until the coloration ceases to 

 be produced. The method permits the determina- 

 tion of one part of .nitric nitrogen in 50,000 parts of 

 water. A nitrite in solution gives the same colora- 

 tion with brucine and sulphuric acid. Besides other 

 means for detecting nitrcus acid is the use in the 

 same manner as sulphuric acid of hydrochloric acid 

 acid not containing free chlorine. It decomposes 

 the nitrites without attacking the nitrates, and en- 

 ables us to detect with brucine a nitrite in presence 

 of a nitrate. 



In the new process for producing chlorine gas for 

 the manufacture of bleaching powder, which is said 

 to have been placed upon a practical basis by a 

 manufacturing house in Glasgow, gaseous hydro- 

 chloric acid is brought in contact with gaseous ni- 

 tric acid in an apparatus through which a constant 

 stream of heated sulphuric acid is flowing. The 

 sulphuric acid absorbs all the water formed by the 

 interaction of the two gases, and is concentrated 

 to be used over again. The gaseous hydrochloric 

 and nitric acids form by their interaction chlorine 

 and a compound of chlorine and nitrous oxide. 

 which are carried forward to a series of towers, 

 in which the nitrous oxide and some hydrochloric 

 acid are removed from the gases, and from which 

 the chlorine in a pure state passes on, either to be 

 absorbed by lime in the usual way with the forma- 

 tion of bleaching powder of high strength, or it 

 may be condensed in suitable apparatus into liquid 

 chlorine. The nitrous gas recovered in the towers 

 is reconverted into nitric acid, and returns to begin 

 the cycle of operations again. An apparatus for 

 the recovery of the nitric acid has also been erected, 

 and works well. It is claimed that by this process 

 all the chlorine in salt can be converted into bleach- 

 ing powder. 



In the Capitaine and Ilerlings process for mak- 

 ing oxalic acid from sawdust. 40 parts of soda lye 

 of 1'33 density, 20 parts of sawdust, and 1'5 part 

 of some substance containing a hydrocarbon (ma- 

 chine oil, vaseline, etc.) are heated at a temperature 



