CHEMICAL SCIENCE. 211 



formed the principal part. These crystalline combinations were 

 obtained even when linseed oil was used. 



The Capillary Attraction of Paper has been employed by M. 

 Schonbein in chemical analysis. He employs in his researches leaves 

 of unsized white paper, suspended at right angles above the surface 

 of the liquid. They are plunged into the liquor to the depth of two 

 or three millimetres, and remain so till the liquor rises to the height of 

 three centimetres. M. Schonbein's experiments show that alkaline, 

 acid, and saline solutions have different degrees of action. For ex- 

 ample, potash, iodide of potassium, and water, are imbibed with dif- 

 ferent degrees of rapidity. The water rises before the others ; the 

 iodide of potassium follows, and the potash comes last. 



Vapors of Saline Solutions. It is known that a saturated solution 

 of salt in water boils at 228 Fah., while pure water boils at 212; 

 but Rudberg says that the vapors of saline solutions under the ordi- 

 nary pressure of the atmosphere have only the temperature that they 

 would possess if they were disengaged from pure water under the 

 same pressure. 



New Frigorific Mixture. Reissig recommends a mixture of sul- 

 phocyanide of potassium and snow or powdered ice, which will pro- 

 duce a reduction of temperature to thirty-five degrees below zero, 

 Fahrenheit. The salt is always recovered by evaporation. 



Chloride of Lime as an Insecticide. Dingler's Polytechnisches 

 Journal says : By scattering chloride of lime on a plank in a stable, all 

 kinds of flies, but more especially biting flies, were quickly got rid of. 

 Sprinkling beds of vegetables with even a weak solution of this salt 

 effectually preserves them from caterpillars, butterflies, slugs, etc. 

 It has the same effect when sprinkled on the foliage of fruit trees. 

 A paste of one part of powdered chloride of lime, and one-half part 

 of some fatty matter, placed in a narrow band round the trunk of the 

 tree, prevents insects from creeping up it. It has ever been noticed 

 that rats and mice quit places in which a certain quantity of chloride 

 of lime has been spread. 



Soapstone Powder as a Lubricator. Soapstone powder, in the 

 form of dust, is proposed as a lubricant for the axles of machines. 

 For this purpose it is prepared as follows: It is first reduced to 

 the condition of very fine powder; then it is washed to remove 

 all gritty particles ; then it is steeped for a short period in dilute 

 muriatic acid (about one quart of acid to twenty of water), in 

 which it is stirred until all particles of iron which it contains are 

 dissolved. The powder is then washed in pure water again to re- 

 move all traces of acid, then it is dried, and is the purified steatite pow- 

 der used for lubrication. It is not used alone, but is mixed with oils 

 and fats, in the proportion of about thirty-five per cent, of the 

 powder added to paraffine, rape, or other oil. This steatite powder 

 mixed with any of the soapy compounds which are also now used in 

 many cases for lubrication also answers a good purpose. It is chiefly 

 intended for heavy machinery, such as the journals of water-wheels, 

 railway and other carriages. 



