The Sampling of Manures and Feeding-si uj^s. 
861 
be sent up for analysis than in the case of a material like 
superphosphate. When taking por tions from a manure delivered in 
bulk, it is essentia] to draw them, not from one part only, but from 
different parts, interior as well as exterior, for considerable differences 
of moisture may be noticeable, and it is only by thus taking 
from various parts that anything like an average sample can be got. 
Shoddy, especially, is a material very likely to gain or lose moisture 
according as the atmosphere is moist or dry, and so, both in selecting 
and in sending samples for analysis, particular care must be taken to 
have and to keep them in the same state as the bulk. To send a 
sample of shoddy simply wrapped in a paper cover, or in a linen bag, 
as is too often done, is to make an analysis quite worthless, and 
unfair alike to analyst, purchaser, and vendor. The discrepancies 
which are sometimes pointed to as occurring between the analyses 
of different analytical chemists, and which are put down to want 
of care or skill on their part, are, in a great number of instances, 
due to samples having undergone change during transit, owing to 
not having been sent in proper covers. 
I might instance a case in which a farmer sent me a sample of 
shoddy, merely wrapped up in brown paper. It gave on analysis 
about 5 1 per cent, of ammonia, but had about 28 per cent, of moisture. 
As the result came below the guarantee given him, the farmer sent 
to two other analysts other samples which he had taken at the 
same time and had since left lying about in paper. Their reports 
showed respectively 6| per cent, and 7 per cent, of ammonia. On 
re-testing, for my own satisfaction, the original sample which had 
been lying about similarly, I obtained results practically agreeing 
with the other chemists' ; but then I found, too, that the percentage 
of moisture, instead of being 28, was now only about 11 per cent., the 
sample having dried to this extent meantime, and my original result 
having been quite correct for the sample as it then was. There were 
really no discrepancies of analysis, but only of the condition in which 
the different samples came to the respective analysts. 
xYs an instance of the injustice that may be done in the sending 
of a sample that is not representative of the bulk, I may mention a 
case which recently occurred. It is well known that superphosphate 
is liable to some extent to "go back," as it is termed, upon keeping, 
showing less soluble phosphate by 2 or 3 per cent., it may be, than 
before. A farmer had deliveries sent to him monthly for a period 
extending over six months, upon a guarantee of a certain percentage 
of soluble phosphate. He took samples from each delivery as it 
came in, but kept these lying about until all six deliveries had come 
in, when he mixed them all together and sent up one sample for 
analysis. Now this was not fair to the vendors, for the real question 
was — what was the quality of each delivery as the contractor 
delivered it ? not, what would a sample test, some of which had been 
lying about for six months or more, other of it for tive months, and 
so on 1 
These examples will show the necessity, in the case of manures, 
of attention being paid to the two conditions I have laid down — viz. : 
