8 ON Tin: MKDICINAL AND TOXICOLOGICAL 



the plant to the analysis of polarized liiz^lit nnder a higli magnify- 

 ing]^ power, Dr. Brewster detected a hcautifnl arrangement of the 

 silicious particles, which are distrihuted in two lines parallel to 

 the axis of the stem, and extending over the M'hole snrface. Each 

 ])article lias a regular axis of double refraction, lie concludes 

 that tlie crystalline portions of silex and other earths, which are 

 found in vegetahle tissues, are not foreign substances of accidental 

 occurrence, but are integral parts of the plant itself, and probably 

 perform some important function in the process of vegetable life 

 (Grev., Fl. Edin., 214). Lind., Xat. Syst. Bot. and Outlines of 

 First Principles, 300. 



E<2uisetum hyemale^ Z. Lenhossek recommends this and the 

 E. limosum, L., as dinretics. A decoction of the dried plant is 

 employed, the fresh being too active. Two to three drachms are 

 added to a pint of water, of which the dose is three to six ounces 

 every three hours (Archiv. Gen. de Med. xvi. 455). In atonic 

 dropsy they are considered too active, causing hematuria. Tliey 

 might be given in the form of powder. Some consider them em- 

 menagogues. Tliey have also been administered to promote the 

 cicatrization of the nlcei*s in phthisis. Hoffman prescribed them 

 in malignant fevers. Mathiole (Comm. 386) states that they con- 

 stipate ; though portions of the plant are eaten in Eome and in 

 Tuscany. One species may be substituted for another (De Cand. 

 Essai, 511). Tlie stems of the E. liyemale are employed in pol- 

 ishing wood, cleaning vessels, c^c. M. Diebold found it to be 

 composed of chlorophylle, wax, yellow extractive matter, gallate 

 of lime, malic acid, oxide of iron, salts, t^'C. MM. Pictet and 

 John found silica in large i^rojtortion. Bull, des Sc. Med. Fer. 

 xvi. 459. Mcrat v.^' De Lens' Diet, de Mat. Med. Ill, 127. 



K<pnsctum limosum. Tlie diuretic power of this plant, also, 

 according to tlie com]taratively recent investigations of Lenhos- 

 sek, in A'^ienna. are well marked, to a sufficient degree to produce 

 hematuria (Edin. Med. and Surg. Jour. 1S27 ; Archiv. Gen. de 

 Med. IG, 450; Jour, de Chim. Med. iii. 554; M. Ilichard, Elem. 

 d'llist. Nat. Med. 11. 55). According to the observer alluded 

 to, the i»lant does not irritate the digestive canal, nor derange the 

 circulation. They are advised in cases of serous accumulations 

 induced by atony. An acid is obtained called equisetic, analo- 

 gous if not similar to maUiCy from the distillation of malic acid. 



