PRUSSIC ACID 



MANURES 



.Tio.1 I iy inn, nt I 1 ..., mi in .laniini \ I'.ioi, uinl tint noiiu were found to C"r 

 .in;. prurtsic acid aa HIH )i, )>nt tii.it all manifested a cyaiiogenetio gluooaide " as- 



1 \vith an en/\me whieh IIIIH the proj>erty <if raiinm^ the nphtlinj uj. .| 

 the glucoside, and the consequent formation of pi-u-,-,!-- a \.-mphti 



<>t this ho gives particular* regarding the glucoaide ilhmrin in the leave* of 

 tl- t'i -. ,,.,/,,! r.i/f/.f,.. -,,-,- p. in-iiij .111,1 ,.| tli,- i;liie<>Miii< in the present 

 plant. "I was aMe," he adds, ' to OHtal.lish thn->- la.t-: fir.-' 



utanif. I an\ prusaic acid as Hurh ; secondly, nil tin- vanetiea, irrespec- 

 tive of tin- <<>!, >nr of tin- petiole or other !>"' 'un-s, i-untain.- : 

 genetic glueosi.le. whii-li varied inneh in amount : thinll'i, tins ^Im -O-K ! IH as- 



''il with an en/.yme whieh has the' property of causing tin- xplitting up of 



aooside, . n.l the <!!-, |nrnt formation of prussic nei,|. AH m the case of 



laavee, it i- "iil\ necessary to enisli tapioea runt with water in order to 



about this change. The amount of prusaic acid varied very much ; from 



Mime r,...ts 1'5 grains of prussic acid per pound of root was obtained, from others 



only one-tenth as mneh." " Hoilin;: the root is quite sufficient not only t,. 



y the en/\ine, but alao to allow the glucoaide to pass out into the 



i , for the root splits up freely." Dunstan and Henry (Pot*. Prop. Beans 

 of Phascolus Innntux, in Journ. Board Agri., 1908, xiv., 730) are of opinion 

 t hut the application of enough heat to destroy the activity of the enzyme present 

 should render such food material harmless. (See Phaseolus lunatus, p. S80.) In 

 M K i ' H i M: tapioca has the same properties and uses as starch. Hanausek (Micro. 

 Tech. Prod. (Winton and Barber, tronsl.), 1907, 45) gives interesting details 

 of his microscopical examinations of the grain. [Cf. Shortt, Man. Ind. Agri., 

 1885,* 307-10 ; Nicholls, Textbook Trop. Agri., 1892, 274-8 ; Pharmacog. Ind., iii., 

 203-5, app. ; Sawyer, Tapioca Cult, in Travancore, in Proc. and Journ. Agri.- 

 Hort. Soc. In>1., April to June, 1897, xi., 666-74 ; Agri. Ledg., 1897, No. 4 ; 

 1900, No. 15 ; 1904, No. 10 ; W. Awtralian Settlers' Guide, and Farmers' Hand- 

 book, 1897, iii., 450 ; Thorpe, Diet. Appl. Chem., 1898, i., 446-7 ; 1899, ii., 503 ; 



1900, iii., 781 ; Woodrow, Qard. in Ind., 1899, 442-3 ; Mukerji, Handbook Ind. Agri., 



1901, 468-77 ; Cassava Poisoning, in Imp. Dept. Agri. W. Ind., 1902, No. 7 

 (Leaflet Series) ; Bull. Dept. Agri. Jamaica, 1903, i., 35-8 ; Board of Trade Journ. 

 Bull. Imp. Inst., May 1903 ; Tracy, Cassava, U.S. Dept. Agri. BuU., 1903, 167.] 



MANURES AND FERTILISERS. The most general ver- 

 nacular names in India for manures are : Tchad, khau, pdus, khadar, 

 sar or sarra, kallar, etc. ; pdusa, Sansk. ; and zibl, Arab. 



Speaking of India as a whole, it may be said that systematic manuring 

 is almost entirely neglected by the Natives. From the most ancient 

 tunes they have been accustomed to observe a casual system of manuring, 

 namely the collection of such substances as are inexpensive and easily 

 obtainable. Moreover, by the very general employment of dried 

 cow-dung as fuel and the utter neglect, through insufficient litter, to 

 conserve cattle urine, they have been deprived of the most important 

 source of all fertilisers and the one readiest to hand, namely farm-yard 

 manure. Caste prejudices, moreover, have to a great extent forbidden 

 the employment of many manures such as bone, animal refuse, night- 

 soil, etc. Still, here and there the value of manure is fully understood 

 (as, for example, in some parts of the Western Presidency) ; and in the 

 treatment of special crops (such as sugar-cane) manuring is regularly 

 practised. But neither example nor precept have, as yet, succeeded in 

 arousing the average Native cultivator to a sense of the benefits likely 

 to accrue from an extended use of manure beyond that pursued by his 

 ancestors. But in all fairness it must be added that in the majority of 

 cases this apathy proceeds far less from ignorance than from inability to 

 purchase soil-fertilisers. The most urgent necessity of agricultural 

 progression in India is, therefore, a system of fuel and fodder reserves 

 calculated to release the supply of farm-yard manure for its more legitimate 

 purpose, that of a soil-fertiliser. 



7G7 



I : .--. | 14 



Ml :. :.. 



D.E.P., 

 v., 167-77 

 Manures. 



I 'nw- .ur._; 

 Fuel. 



Ossts. 



Sugar-cane. 



Inability. 



Fnel and Fodder 

 BSM <-. 



