Chemistry and Physics. 83 



SCIENTIFIC INTELLIGENCE. 



I. Chemistry and Physics. 



1 . The Production of Pure Sodium Hydroxide for Laboratory 

 Uses. — On account of the danger in dissolving any considerable 



amount of metallic sodium directly in water, because of the very 

 violent explosions that are likely to take place from an unex- 

 plained cause, even with bright metallic sodium, F. W. Kuster 

 has devised a method for effecting this solution slowly by the 

 help of moist air, and has thus obtained a very satisfactory and 

 cheap caustic alkali solution. He places a bell-jar in a large, flat 

 dish in which there is sufficient water to make a water-seal, and 

 under the ball-jar he places a platinum, silver, or nickel dish, cru- 

 cible, or wide-necked flask, as a receptacle for the caustic solution. 

 Above the receptacle is placed upon a tripod a piece of nickel 

 wire gauze, bent into a conical shape with its apex downward, and 

 in the cone pieces of sodium are placed after the outer crust has 

 been cut off. The sodium begins at once to deliquesce while 

 bubbles of hydrogen escape through the water-seal, and the 

 resulting sodium hydroxide solution drops as a very concentrated, 

 oily liquid from the point of the cone into the dish below. The 

 operation goes on until all the sodium has been used up, and at 

 last certain impurities of the sodium remain upon the wire-gauze, 

 so that this process gives a purer product than direct solution. 

 The solution thus obtained is of about 40 per cent strength, and it 

 may be kept absolutely free from carbonate. — Zeitschr. anorgan. 

 Chem., xli, 474. h. l. w. 



2. The Production of Magnetic Alloys from Non- Magnetic 

 Metals. — R. A. Hadfikld, who has produced the well-known 

 non-magnetic alloy of iron and manganese known as "manganese 

 steel," calls attention to the interesting fact that a magnetic alloy 

 can be produced from the non-magnetic metals, copper, alumin- 

 ium, and manganese. A sample of this alloy, which appears to 

 have been prepared by Dr. F. Heusler, contains 60 per cent cop- 

 per, 25 to 27 per cent manganese, 12 per cent aluminium, 6 to 7 

 per cent silicon, 0*5 to 1 per cent carbon and probably 0*5 per cent 

 iron ; but samples containing absolutely no iron had exactly the 

 same magnetic properties. It has been found that no alloy of 

 copper and aluminium is magnetic, hence it appears that the 

 magnetic properties of the alloy are due to manganese, which, 

 curiously enough, produces the non-magnetic alloy with iron. 

 It is to be observed, however, that the alloy under consideration 

 requires the presence of a certain amount of aluminium in order 

 that it may be magnetic, and that with fairly constant contents 

 of manganese amounting to 25 to 28 per cent, the maximum 

 "magnetizability" is reached when 14 per cent of aluminium is 

 present. — Chem. News, xc, 180. h. l. w. 



3. Ozobenzol. — A product of the action of ozone upon benzol 



