Scientific Intelligence. 157 



formed first into sugar of grapes, then into ulmie acid, and (if atmo- 

 spheric air is present) into formic acid. 2nd. When cane sugar is 

 changed into sugar of grapes, the action of the acids takes place even 

 at common temperatures. 3rd. That the smallest quantity of acid 

 acts in the same manner hut more slowly. An acid less dilute will 

 act more quickly than an acid more dilute. 4th. Dilute acids under 

 the action of atmospheric air cannot transform sugar into formic acid. 

 5th. The action of alkalies upon sugar is identical with that of 

 acids. His experiments confirm the accuracy of the composition 

 assigned to ulmic acid hy Boullay, viz. C 2 HO. Ulmic acid may he 

 readily formed by boiling together 10 parts sugar, 30 water, and 1 

 concentrated sulphuric acid. In three quarters of an hour a scum 

 forms on the surface which may be skimmed off; in a few minutes it 

 is formed anew. This scum is ulmic acid with a little ulmin, which 

 may be separated by ammonia. Water should be added occasionally 

 in order to re-place what evaporates. — {Ann. de Chim. lix. 407.) 



VI. — Chloro-benzine and Chloro-benzide. 



Chloro-benzine is formed, by exposing benzine and chlorine in a 

 close vessel to the action of the sun. A white vapour forms and is 

 gradually deposited in crystals. It is insoluble in water, little soluble 

 in alcohol, but more soluble in ether. Fuses at 269^°. It consists 

 of carbon 25*14 ■ hydrogen 2-06 ; chlorine 72-80. This is equiva- 

 lent to cs mi ci i|. 



Chloro-benzide may be readily formed by subjecting chloro-benzine 

 to distillation, mixed with an excess of hydrate of barytes or lime. 

 Water, and a chloride is formed, and chloro-benzide passes over. 

 Chloro-benzide is an oily colourless liquid. Specific gravity 1-457. 

 Insoluble in water, very soluble in alcohol, ether and benzine. Not 

 altered by acids and alkalies. Boiling point 410°. It consists of 

 carbon 39-91; hydrogen 1-62; chlorine 58-47. The density of 

 its vapour was found to be 6-37. This corresponds with 6 vol. 

 carbon vapor =2-4990, 1| hydrogen = -991, 1J chlorine =3*75= 

 6-24. — (Poggendorff's Ann. xxxv. 370.) 



VII. — Silica, in Plants. 



Struve has obtained the following results from an examination of 

 the ashes of several plants. 



(Erdmann tend Schweigger Sbidel's Journal, v. 462.) 



