666 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



Preservation of Milk. 



The irerms to which Mr. Williamson attributes the fermenta- 

 tion of milk are not destroyed by ordinary boiling, but if the 

 milk be boiled under a pressure of about 22 pounds to the inch, 

 he asserts their destruction is effected, after which the milk may 

 be preserved in air-tight cans any length of time. 



Magnet made of Ikon Shavings. 

 A new magnet of considerable power has been introduced by 

 M. Greiss, which is composed of the long spirals formed by a 

 chisel in turning iron. He states tliat the magnetism of these spi- 

 rals is of a very permanent nature. The end of the spiral which 

 the chisel first touches is invariably the south pole. 



Explorations in Africa. 

 The Geographical Society of France are raising funds to enable 

 M. Les^aiut to explore certain unknown parts of Central Africa, 

 especially the territory between the basin of the Upper Nile and 

 the French colony of Gaboon. M. Lessaint believes the central 

 platteau is fertile, and its inhabitants will doubtless furnish inte- 

 resting subjects for ethnologists. 



Artificial Mixture for Busts. 

 Chloride of magnesium, is convertible into anhydrous of mag- 

 nesia, which, when soaked in water and formed into lumps, 

 becomes hard and transparent as alabaster. This, if pulverized 

 and mixed with an equal quantity of powdered marble, form«, a 

 substance which, after being pressed into a mold and exposed for 

 some time to the action of water, is suitable for statuary. 



Laurite. 



A new mineral has been discovered by Wohler in the fine 

 grained platinum ore from Borneo, to which he has given the 

 name laurite. It is a sulphide of ruthenium and osmium, consist- 

 ing of small grains of iron-black color, of high lustre, harder than 

 quartz. Its analysis gave ruthenium 65.18, osmium 3,03, sulphur 

 31.79. This is the first sulphide found in the group of platina 

 metals. 



To RESTORE Stained Glass. 



M. Chevreul states that old and dim stained glass of windows 

 can be restored to its original brilliancy by a simple process. The 



