surface pale pink, with fine longitudinal striae: no marked odour; astrin- 

 gent taste. 



Tinctura Hamamelidis. Dose, 30-60 min.; 2-4 c.c. 

 10; Alcohol 45%, 100: by percolation. 



Hamamelidis Folia. The leaves fresh and dried of Hamamelis 

 virginiana. Broadly oval in outline, 3-6 inches long; upper surface dark- 

 green to brownish, the lower paler in colour; no marked odour; an astrin- 

 gent, slightly bitter taste. 



Extractum Hamamelidis Liquidum. Dose, 5-15 min.; 0.3-1 c.c. 

 An alcohol extract. 



Unguentum Hamamelidis. 10; Hydrous Wool Fat, 90. 



Liquor Hamamelidis. An alcoholic solution made from the fresh 

 leaves by maceration in alcohol and distillation. 



Hemidesmi Radix. Hemidesmus Root. The dried root of Hemidesi 

 mus Indicus. The root is long, nearly cylindrical, tortuous, and long- 

 tudinally furrowed; about 1/4 inch thick; brownish in colour: odour 

 fragrant; taste sweet. 



Syrupus Hemidesmi. Dose, 30-60 min.; 2-4 c.c. 

 10; Sugar, 70; Water, 50. 



HIRUDO. LEECHES. Sanguisuga medicinalis and S officinalis. 



Homatropinse Hydrobromidum. Homatropine Hydrobro- 

 mide. Dose, 1/80-1/20 gr.; 3/4-3 mgms. 



A white crystalline powder or aggregation of crystals. Soluble 1 in 6 of 

 water, 1 in 18 of alcohol. I ncompatibles, as for alkaloids. 



lamellae Homatropinae. Gelatin disks each containing 1/100 



HYDRARGYRUM. MERCURY. 



Incompatibility, most salts of mercury are insoluble and hence the 

 range of incompatibility of the soluble salts is a wide one: amongst the 

 substances producing precipitation in solution of mercuric salts are al- 

 kali hydrates or carbonates including ammonium, lime-water, borax, 

 soluble iodides and bromides (precipitate soluble in excess), phosphates. 

 hypophosphites, and sulphites, arsenites, ferrous salts, tartarated anti- 

 mony, tannic acid, albumin, gelatin, some bitter principles, and gluco- 

 sides. With mercurous salts the reactions are similar with the addition 

 that iodides lead to the formation of metallic mercury and mercuric iodide, 

 the same is true of chlorides; oxidising reagents lead to the formation of 

 mercuric salts; cane-sugar, milk-sugar, acacia and tragacanth reduce mer- 

 >curous salts. 



1 Hydrargyrum. A silvery white metal. Volatilises with heat. 



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