Calligraphy, 377 



affect the same alcalies dissolved in water. This phenom- 

 enon is owing to the formation of a particular acid by the 

 reaction of the carburet and alcohol, promoted by the al- 

 cali. 



The new acid contains sulphur, carbon, and hydrogene. 

 It is probable that the two first perform the same function 

 in this combination, that cyanogen does in the hydro-cya- 

 nic acid, and that they unite in a different proportion from 

 that in which they are combined in common carburet of 

 sulphur. Prof. Z. has given the name of Xanthogene, 

 (from ^av^os, yellow, and ysMva^^,) to this compound radical, 

 because it forms combinations of a yellow color with some 

 of the metals ; and he has named the new compound, the 

 hydroxanthic acid. At commmon temperatures it has the 

 appearance of a colourless, translucid oil. It is heavier than 

 water, and does not combine with it. 



7* Calligraphy. — M. LeRoi has contrived a new and 

 very simple method for teaching the art of writing. A thin 

 and perfectly transparent plate of horn, of the usual size of 

 a leaf of paper, has the polish removed from one of its 

 sides. When laid upon the copy the hand of a child easily 

 traces the letters upon the unpolished side, which neither 

 absorbs the ink nor allows it to spread. When the whole 

 plate is written over, the ink is washed off with water, and 

 4s ready for a new exercise. Thus the same horn which is 

 not liable to break, may serve indefinitely, and by this 

 means produce a great economy of paper — a consideration 

 not to be neglected. Several analogous methods have 

 been adopted both in England and France. Oiled paper, 

 glass, a machine for guiding the pupil's hand, &;c., have 

 been used, but it is evident that the method of M. Le Roi 

 has none of their imperfections. The minister of ihe inte- 

 rior, who has witnessed the success obtained by this inven- 

 tion, has rewarded the author ; and the societies of encour- 

 agement, and of elementary instruction, as well as the wri- 

 ting academy, have expressed their approbation of this new 

 process. Mothers may teach their children to write in the 

 absence of the master, or even dispense with his attendance 

 by the adoption of the horn. 



Vol. Vlf.— No, 2. 48 



