Chemical Catechism. — Galvanism. 233 



^vith chemical science. And in ord-er to remove in 

 some measure the dilHcuhies which such persons lind in 

 acquiring chemical knowledge, we understand that he has 

 observed the utmost simplicity of language and arranore- 

 ment, and has varied the mode of putting the o,ucstioiK, 

 whenever tlie subjects seemed to require more than ordinary 

 elucidation. A very copious collection of Notes will be 

 subjoined for the use of the preceptor in explaining the 

 doctrines taught in the body of the work, and for tlie pur- 

 pose of pointing out the connection which subsists between 

 chemistry and the arts, and showing the various ways in 

 which the several substances in nature are applied in the 

 manufactures of the country. We understand that he in- 

 tends to annex a vocabulary of chemical terms, various 

 useful tables, a chapter of amusing experiments, and re- 

 ferences to the most approved treatises in every department 

 of the science. The work (now in the press) will be 

 ready for publication the beginning of February. It will 

 be entitled a Chemical Catechism, and will be comprised 

 in one volume, octavo. 



GALVANISM. 



Doctor Joseph Baronio has published at Milan the de- 

 scription of a Galvanic pile, formed of vegetable materials- 

 only. The author cut disks of horse-radish and beet-root 

 of about two inches in diameter; aftewards he pr .pared 

 equal disks of ualnut-tree wood. The latter disks are sa 

 raised at their edges as to contain a little solution of acidu- 

 lous tartrite of potash in vinegar, in which they have beea 

 previously boiled, to purge them from the resinous princi- 

 ple which the walnut-tree contains. By forming the pile 

 with sixty pairs of disks, one of horse-radish, the other of 

 beet-root, v»'ith disks of wood between the pairs, and iu 

 each of these a little of the abovemenlioned solution, he 

 cblalncd Galvanic effects, in a prepared Irog, of which, by 

 means of a leaf of Cochlearia, lie made the spinal marrow 

 communicate with the base of the pile, while by a double 

 band of gray paper, well moistened with vinegar, he made 

 its muscles coujmunicaie with the lop of the pile. 



The description of tlie apparatus is so clear and detailed, 

 a« to p-ove that the author, who is already known by se- 

 veral productions in physicdl science, wishes that philoso- 

 phers and amateurs should repeat his experiment. 



For horse-radish and beet-root, the author has already 

 substituted disks of other vegetables with equal success, 

 and he flatters himself that tlicse will serve to extend the 



application 



