452 
Potash in Castor Cake. 
The amount of potash in castor cake appears to 
Jiave been very seldom determined. The late Mr. 
Prin-iie found nearly 2 per cent, in a samj.h! of 
.secondary quality, wiiile the author in a similar 
quality found only -91 per cent. In drawin;< out 
the tables for manuring of tea the author f(Hin<l 
it necessary to take account of the j)otash in 
second-cla.'^s castor cake, and iiavinj^- only de- 
termined it once himself, he gave weight to Mr. 
Pringle's analysis, taking the figure at I-.") a 
little above the mean of the two aiial\ ses. Three 
subsequent determinations by Mr. \\'. \\. JJm-. 
nett, F,c.s., however, have confirmeil the author's 
figures, the results obtained being 02, -94, l l.">, 
so that 1 per cent, may be taken as quite higll 
enough to represent the potash in second-class cas- 
tor as cake imported into f'eylon. The followin" 
details of Mr. I'ringle's analysis and of the 
author's. It would ajjjiear as if the jiotasli were 
replaceable to some extent by lime, Mr. Printile 
having found only a tiace of lime, while tlie 
author found -78 per cent. If the class of castor 
cake represented by Mr. Pringle's analysis can 
be freely obtained, it would be worth* to the 
Ceylon planter P2 per tons for its jiotash more 
than that represented by the authoi's analj'sis. 
The following are details of the two analyses: 
Analyses of two samples of Castor Cake. 
Seeondanj qualitij 
Pringle. 
Author. 
Moisture 
6-71 
90C 
Organic matter 
87-30 
8.3- 19 
Ash 
5-99 
7 21 
100-00 
100-00 
Nitrogen ... 
505 
4-89 
Sand 
-8,3 
2-82 
SoluLleAsh 
5-lG 
4-39 
Potash 
1-98 
-91 
Lime 
■09 
-78 
Phosphoric Acid 
1-21 
1-24 
For the determination of potash and other 
mineral constituents in castor cake of the hrst 
quality, I submitted a sample of wliat is .sold 
in Colombo as best quality to jMr. Tatlock, 
Glasgow, who for quarter of a century has been 
regarded as an authority on the det ermination of 
potash, and whose modification of th-i general 
process is the one generally adopted in agricul- 
tural laboratories. The following -were the 
results obtained in his laboratory. 
Mineral Constitnents of Castor Cake. Best quality^ 
Per cent. 
Lime ... ... .. -87 
Phosphoric Acid 
Potash 
Ash 
2-94 
1-25 
9-42 
S-40 
Water 
Of the samples submitted to me the richest 
white castor cake contained nitrogen equal to 
9-.S5 per cent, of ammonia ; hut according to 
Mr. Pringle it can be produced with nitrogen 
equal to 10 per cent, of ammonia Of those 
samples analysed in 1891 the nitrogen in no case 
quite reached the equivalent of 8 per cent of 
ammonia. The following are some examples of 
the castor cake of commerce in Ceylon: — 
g 
a, 
V s 
Z. a; 
1- « 
e t~. r. 
i i'- 
rr, 
1 
|! 
ff; OJ X "5 
7" 'P 
>C * l.'S c< 
b 
e s 
£. u 
•J 
1 a- 
Oi 0 p 
I ^ X ^ 
0 
© 
® 
X©«ft 3 
•s I- r>. « 
'2 — "* 1 0 
4 « 1 ? 
© 0 0 
i 
•b 1' » 
V a 
o 
C =1 
V~ ^ 
0 C C5 
« ac' 
0 1'- e n 
I. 
o c 
CI 
iO •« 0 
7 * 
00 © 0 
© 
© 
1^ — ao IM 
0* « w « 
per 
cent. 
1^: v. i- 
35 t~ CC 
i-- tN 0: 
9 
6 
© 
^ X 35 ao 
«9 « 91 
per 
cent. 
r- i-t 1 » 
OS 0 © 
1 
S 1 
i 
CM «~ © M5 
« ® X OS 
'.S 
'c 
S 1 
* - - 
.i. tv - I. S — 
- t2 s 
- ^ «< W V2 a; 
The following is an inferior sample: — 
Moisture 
Organic matter 
Ash 
per cent. 
910 
. 80-14 
. 10-76 
100-00 
3- 86 
4- 69 
6-48 
4-28 
of only 
Nitrogen 
Equ,al to Ammonia 
Soluble .Vsh ... 
Sand 
Analysis shows this sample to be „. 
half the commercial value in Colombo of the 
second example in previous page, and of con- 
siderably less than half the value to the planter 
on a distant estate. 
The abnormal composition of the following 
samples was due to the presence of bone dust :— 
Analysis of CaMor Cake containing Bone Dust. 
per cent. 
7-75 
... 73-65 
18-60 
Moisture 
Organic matter 
Ash 
Nitrogen 
Equal to Anmionia ... ..' 
Soluble Ash ... ... 
Phosphoric Acid .. 
Equal to Tri basic Pho.sphate of Lime 
(To he continued.) 
100-00 
5- 75 
6- 98 
13-71 
4-87 
10-64 
