



Chemistry and Physics. 43 1 



water or alcohol they are resolved into terpinol and hydrochloric acid 

 by assimilating one eq. of water. The same compound is directly 

 formed by the action of hydrochloric acid gas on terpinol ; it is iso- 

 meric with the hydrochloric compound of oil of lemons, but differs 

 from it in its properties. The action of anhydrous phosphoric acid 



upon terebol removes all the oxygen as water, and yields an oil which 

 is identical in composition with oil of turpentine. 



[Dr. List appears to have overlooked the important relations of this 

 substance as one of a series of homologous oils, four of which have 

 been studied. The formula which he proposes should be doubled to 

 accord with the equivalents adopted by the German chemists, and then 

 writing its formula C 40 H 68 2 , we have a number of equivalents of 

 hydrogen divisible by 4. But in M. Gerhardt's notation its formula 

 will be C 2o H 34 O, referring it to the form R~ 6 0. We have of this series 

 by the discovery of terpinol at least five known compounds; phenol 

 I C 6 H 6 O, anisol C 7 H 8 O, carvacrol C 10 H l4 O, cedrol C 16 H 26 O, 



and terpinol C 20 H 34 O, which appear to be homologous. The car- 

 bohydrogen which the latter yields by anhydrous phosphoric acid, will 

 be probably C 20 H 32 , homologous with cerdrene which is formed by 

 the same process from cedrol, and with cinnamene. These homologies 

 point out an interesting field for research in examining the reactions of 

 the last three oils with chlorine, nitric acid and ammonia.] 



T. S H. 



6. Improved Method of preserving Milk, patented by F. H. F. Louis, 

 (Chem. Gaz., Jan., 1849.) — The milk is to be mixed with well clarified 

 raw sugar, 4 oz. to the gallon. It is then to be evaporated with agita- 

 tion ; when nearly solid it must be pressed into cakes of suitable size. 



Steam may be used for the evaporation, or if time is no object, spon- 

 taneous evaporation in very shallow pans, with the fluid not more than 

 one-tenth of an inch in depth, or a drying chamber may be used, the 

 temperature not to exceed 122° F. 



The cakes remain sweet and fresh for a long time and are soluble in 

 warm water. Another process is, to heat the sweetened milk nearly to 

 the boiling point, and before it becomes cold to curdle it by rennet or a 

 weak acid. The curd is separated from the whey, and by strong pres- 

 sure after washing in cold water, it is obtained free from adhering water. 

 The whey is to be evaporated to dryness. The curd placed over a 

 slow fire is continually stirred, and the dried whey added very gradu- 

 ally, with a small portion of bicarbonate of soda. After a while the 

 ingredients melt and unite. A small quantity of finely pulverized gum- 

 dragon, hastens the solidification. 



Cream may be preserved by the same methods. 



G. C. Sch^ffer. 



7. On a New Method for Amalgamating Zinc; by Prof. O. N. Stod- 

 dard, Miami University, Ohio, (in a letter to one of the Editors.) — This 

 method consists in the employment of double chlorid of zinc and am- 

 monia, (the same solution which is so useful in soldering iron and steel. 



The zinc to be amalgamated, is heated to about 450° F. or 500° F., 

 and the liquid applied by a cloth or sponge and the mercury suffered 

 to flow immediately over the surface while still moist. 



