179-3 
CHEMICAL CONSTITUENTS, Silicia, SiO,.—This oxide of silicium is present 
in the plant in large quantities, ranging, according to different authorities, from 
7.5 to 41.2 per cent. of the whole herb. 
Equisetic Acid, Aconitic Acid, C,H,O,.—This acid was determined in 4. fu- 
watile as magnesium aconitate by Braconnot, who considers it present in the other 
species of the genus. It forms in highly acid klinorhombic prisms, fusing at about 
130° (266° F.), and soluble in both water and alcohol. This acid has also been 
called “mallic,” because it is formed upon the destructive distillation of mallic 
acid; but it fails to answer to the properties of that acid, as well as to its com- 
position, C,H,Q,. 
PHYSIOLOGICAL ACTION.—Dr. Hugh M. Smith states* the following symp- 
toms arising in persons taking from 50 to 150 drops‘of the tincture: Greatly 
increased appetite ; severe sharp pain, with soreness, in the lower abdomen ; pain, 
tenderness, and distention of the bladder, with frequent urging to urinate; sharp 
pain along the urethra, burning and aching in the penis and testicles when urinat- 
ing, with soreness of the testicles and spermatic cord; dull pain and soreness in 
the back, with.prostration. 
It is said that where cattle have been given too large quantities of an infusion 
as a diuretic, it has caused the voidance of blood. 
DESCRIPTION OF PLATE 179. 
1. Lower portion of stem. 
2. Upper portion of stem. 
(Two feet of stem between Nos. 1 and 2 left out.) 
3. Fruiting head (enlarged. ) 
4. Sporangia, outer; 5. inner view. 
6. Damp spore x 200. 
7. Dry spore x 200. 
8. Stoma x 200. 
: From Binghamton, N. Y., May 1, 1884. 
esi seen mate 
* Thesis, N. Y. Hom. Med. Coll., 1876; Allen, Ency. Pure Mat. Med., vol. iv., pp. 204-210. 
