2 BULLETIN 165, U. S. DEPARTMENT OF AGRICULTURE. 



The following formulas are typical examples of the variation in 

 the amount of ingredients and the cost per 100 gallons: 



No. 3. 



No.l. 



No. 2. 



2.8 



8 



1.6 



6 



100 



100 



31 



69 



Quassia chips pounds. 



Whale-oil soap do 1.6 6 6 



Water gallons.. 100 100 100 



Cost per 100 gallons cents.. 31 69 74.2 



These formulas are concocted differently by different growers. 



Some soak the chips 24 hours in a barrel of water and then boil them 



for 2 hours. Some boil them for 2 hours without previous soaking, 



and others boil them with the whale-oil soap. The several formulas 



and methods of preparation all have their advocates among the hop 



growers. 



CHEMICAL LITERATURE ON QUASSIIN. 



The quassia chips commonly used in preparing spray solutions are 

 the wood of the Jamaica quassia (Picrasma excelsa Swz.). The 

 literature on the chemical nature of quassiin, the active principle of 

 quassia wood, was found to be very limited, but the few important 

 references that the writer was able to obtain are discussed below. 



The wood of Picrasma excelsa (Swz.) Planch. (Quassia e Swz.; Q. polygama Lind- 

 say; Piceaena e Lindl.; Simaruba e D. C.) or of Quassia amara L. (Fam. Simarubacese). 



Description. — Jamaica quassia. Occurring in various forms, usually chips, raspings, 

 or billets, yellowish white or pale yellow, and of rather coarse texture; odor slight; 

 taste intensely bitter; medullary rays containing tetragonal prisms or small, arrow- 

 shaped crystals of calcium oxylate. Billets of Jamaica quassia are usually 12.5 cm. 

 or more in diameter; in tangential section the medullary rays are mostly 3 to 5 rows 

 of cells in width. 



Surinam quassia. Occurring usually in billets not exceeding 7.5 cm. in diameter; 

 the wood is heavier, harder, and more deeply colored than that of Jamaica quassia, 

 and the medullary rays in tangential section are mostly 1 or 2 rows of cells in width. 



Constituents. — Although Jamaica quassia is said to contain traces of a yellowish 

 alkaloid, giving a fine blue fluorescence with acidulated alcohol, the important bitter 

 principle is a neutral, crystalline substance, commonly known as quassiin, but deter- 

 mined by Massute to be a mixture of two crystalline bodies, which he denominated 

 a- and /?- picrasmin. 



Quassiin is extracted by neutralizing the aqueous infusion with soda, precipitating 

 with tannin and decomposing the precipitate with lead oxide or lime. It is commonly 

 said to exist to the extent of only 0.05 to 0.15 per cent, but really exists in much larger 

 amount, Wiggers says 0.75 per cent. This discrepancy is probably due to the fact that 

 it is difficult to procure in the pure state, and that the purification processes involve 

 considerable loss. Quassiin crystallizes in needles or prisms, and is soluble in alcohol 

 and in chloroform and in 1,200 parts of cold water. Its bitterness is most intense. The 

 ar-picrasmin (C 35 H 46 O 10 ) melts at 204° C. The /?-picrasmin (C 36 H 4S O 10 ) at 209° to 

 212° C. (408.2 o ^413.6° F.). The bitter principle of Surinam quassia is closely related 

 and of similar action, but not identical. 1 To it the name quassin is commonly 

 applied. 



1 Hare, H. A., Caspari, O, and Rusby, H. H. National Standard Dispensatory, ed. 2, revised and 

 enlarged, p. 1334, Philadelphia, 1909. 



