120 



KANSAS ACADEMY OF SCIENCE. 



= {^-h)l ] J 



(35) 



dx ' " *- ?2 



From (35) we see that the increment of M2 is negative, as x varies from ?i + ^2 



to I; hence, M2 is greatest for a; := Jj -j- I2. 



dM'," ^ 



= (Q" + w)^ — Rj = o. 



dz 



z = {-l+j)[^ql-\-w{l,+l,)~\ 



ql2 + w{l-^ + ^2)2 

 21^ 



(36) 



The value of z in (36), and the corresponding value of x substituted in (34), will 

 give the value of (M2 )max. 



M'3" == (g + iv) (— - ) and (M3 )max. = (g + zt,) ^ (37) 



THE EXTEACTIVE YIELD OF VARIOUS IMPORTANT VEGETABLE 

 MEDICINAL SUBSTANCES. 



BY PBOF. L. E. SAYRE, UNIVEBSITY OF KANSAS. 



The amount of extractive yielded by a fibrous drug, while it does not afiford a 

 sure test of its value, furnishes a data by which the working pharmacist and physi- 

 cian may judge of the quality of the material in hand. It also gives a means by 

 which such adulterations as insoluble woody fiber may be detected. There have not 

 been to my knowledge any reliable tables made out of this kind, and at the sugges- 

 tion of a few medical colleagues, I have prepared the following table, which is the 

 result of my own examination of the standard drugs of the market. 



Table showing the percentage of extractive, dried at 100° C, contained in prom- 

 inent medicinal vegetable substances of the market. 



(The solvents employed being those of the United States Pharmacopoeia. ) 



Per Cent. 



Aconite 14.15 



Apocynum cannabinum 1 4.40 



Belladonna leaves 22.70 



Burdock root 24.00 



Buchu leaves 23.30 



Belladonna root 9.65 



Colchicum root 19.45 



Cannabis indica 13.00 



Coca leaves 24.70 



Conium 28.60 



Digitalis leaves 34.10 



Gelseminum root 11.60 



Hydrastis 23.20 



HyoscyamuB leaves 19.50 



Per Cent. 



Hydrangia 9.06 



Ipecac root 12.45 



Convalluria 33.50 



Mezereum 11.80 



Nux vomica 13.70 



Podophyllum 13.80 



Poke root 17.12 



Pleurisy root 25.20 



Stramonium seed 14.10 



Veratrum 18.00 



Viburnum opulus 15.20 



Yerba santa 31.95 



Juborandi 23.58 



