58S 
THE TROPICAL AGRICULTURIST. [March i, 1894. 
Valuation of Manures. 
Wliei'ever tlie Jiianures of coinnierce are used 
to a considerable extent, tlie price i.s based on tlie 
chemical composition as determined by analysis. 
The manure is either sold at so mucli per ton with 
a {guaranteed analysis, or it may be sold at so 
much per unit of one or more of the three imitort- 
antconstituents : nitroj^en (or ammonia), jibosplioiic 
acid (or phosphate of lime) and potash, found by 
analysis to be actually present. 
By the unit of any ingredient is meant tlie one- 
hundredth part of a ton of that ingredient. The 
unit has a commercial value affixed to it based 
on the price of the ingredient in manures at 
port. Tlie p) ice of a unit is therefore not a fixed 
quantity ; but fluctuates according to the law 
of supply and demand. It has to be adjusteil 
from time to time as the market varies when 
commercial transactions are conducted on the 
basis of analysis. It will, however, be of consider- 
able use if I give here a list of values of units 
of manurial ingredients, even although, by the 
time it is in the hands of the public, its accuracy 
will be only approximate. 
The following is the rule for finding the com- 
niercial value of a manu)'e at port from its 
analysis. Multiply the ])er«entage of the valualile 
ingredient in the analysis by thepjice of the units, 
the product or where there is more than one 
valuable ingredient, the sum of the products will 
give the commevcial value of the maiiui e : — 
Table showing the commercial valve In Colombo 
of one-hundredth part of a ton of the imporfnnl 
Gonstitnents of manure : — 
K. c. 
* Ammonia in .sulphate of ammonia con- 
taining 24 per cent of ammonia x2 XS 
Ammonia — equivalent in nitrate of 
potash containing nitrogen equal to 
14 per cent of ammonia ... ... 1"2 Jo 
Ammonia — equivalent in nitrate of soda 
containing nitrogen eqxial to 19 per 
cent of ammonia ... 
9 
25 
Ammonia — equivalent in steamed bones 
9 
00 
Ammonia— equivalent in dried blood. 
oil cakes and fish manure ... 
7 
00 
Ammonia— equivalent in bone dust 
(i 
75 
Phosphate of lime soluble as in 40 to 
50 per cent superphosphate 
.3 
25 
Phosphate of lime insoluble as in fish 
manure and steamed bones 
0 
90 
Phosphate of lime insoluble as in bone 
dust 
0 
75 
Phosphate of lime leckoned as tribasic 
in basic slag 
1 
92 
Phosphate of lime insokible in finely- 
78 
ground mineral pliosjihates 
] 
Phosphates in oil cakes 
0 
80 
Potash in nitrate of potash ... 
2 
50 
Potash in nitrate of potash imported 
rom Europe 
3 
90 
Potash in sulphate of potash 27 % 
4 
89 
Do in kainit 12 % 
6 
27 
Do in muriate of potash 50 % 
64 
Do in oil cakes .. 
•> 
00 
Soluble ash in oil cakes 
0 
75 
* Jjiable to considerable fluctuation, 
A few examples of the method of using the units 
for the valuation of manures will ma^le the matter 
clear : thus, suppose we have a goo<l sample of 
uitre containing 12-45 per cent of nitrogen whidi 
IS equivalent to 15 ) 1 per < ent r.f amnionia and 
41-92 per cent of potash. 
Ammonia l.VJl y J{12 15 = KlM .-iH 
lotash 41-92 y i-M 104 SO 
Value per ton in Colomljo K2MS a» 
Take an example of steamed bones containin- 
2-o2 per cent of nitrogen equivalent to 3-06 per cent 
of ammonia and 50 5 i>er cent of phosphate ..f 
lime. 
Ammonia 3 06 x R<» = }{27 .'-,4 
Phosphate of 
lime 50-5(J ^ Ho(i-9»» 45 4.'; 
Value per ton in Colombo ... l{7'j y.i 
Take an example of go<id Ijone diwt containin" 
nitrogen equal to 4-5 per cent of aniiiioDia and 
50 per cent of phosphate of lime. 
Ammonia 4 5 i{6 75 -RaO :t8 
J'hosphate of 
50 -y. Ko-75 =- 5 25 
Value per ton in Colombo .. 67 88 
Take an examjile of gootl castor cake contain 
ing 7 i)er cent nitrogen equal to 85 per ceni 
of ammonia and 7 l>er cent of scduble asli. 
Ammonia 85 K7 =K59 50 
Soluble a.sh 7 >r KO-75 = 5 25 
Value per ton in Colombo ...64 75 
La.stly, take an example of inferior castor cake 
containing nitrogen equal to ammonia 4 69 iiercent 
and soluble ash 6 48 j>er cent. 
Ammonia 4-69 x K7 --^K32 8a 
Soluble ash 6 48 x ,, 0-75 = 4 86 
\'alue per ton in Colombo ... R37 69 
It will be abundantly evident from the last two 
examples, that, from a commercial point of view, 
when a manure is purchased on the l>ajsis of its 
analysis, for application at no great distance 
from tlie place of purcha-se, it does not greatly 
matter whether it is rich or comparatively poor in 
fertilising ingredients : but the economy of pur 
chasing a m.auure rich in fertilising ingredients is 
apparent when the manure ha-s to be carrie<l a 
considerable distance. Thus, in the tv.o examples 
of castor cake just referred to, one ton of the 
better quality has a manurial value equal to 1-72 
tons of the inferior quality. Let us suppose each 
manure lias to be carried a hundred miles at )2J 
cents per mile per ton, the cost on the estate of 
equal quantities of the valuable constituents of 
the manures may be calculated thus : 
Cost of 1 ton castor cake good quality 
.at port ■==R64 75 
carnage on same for 100 mUes at 124 cents =12 50 
Cost on the estate ... R77 05 
Cost of 1-72 tons inferior castor cake at 
^Poyt ... =R64 75 
Carriageonsamefor 100 miles at 12icts. =21 50 
Cost on the Estate R86 2.'> 
By purchasing one ton of the manure of <'x od 
quality the planter would thus .save R9 in carria< e 
comparetl to \n hat he would have to pay for the 
same manurial ingredients in the inferior manure. 
