790 REPORT—1904. 
daily in the pit, when it was found that the loss of nitrogen was reduced from 
27°8 per cent. to 7-1 per cent. In this connection Pfeiffer says: ‘The cost, how- 
ever, was nearly a mark for each kilo. of nitrogen conserved, and the use of 
sulphuric acid is associated with so many drawbacks that its employment cannot 
be recommended.’ 
Schneidewind came to a similar conclusion, and thus expresses himself: ‘ As a 
result of numerous conservation experiments carried out with various quantities 
of sulphuric acid, and with various acid sulphates, we cannot advise the use of 
these substances.’ 
But although no benefits have been obtained from the use of the substances 
indicated, some useful information is available as to the advantages of giving 
attention in other directions to the management of farmyard manure. Hansen 
and Giinther took four lots of manure of similar character, storing two of the lots 
in pits and placing the other two in heaps in the open field. From the end of 
September till the middle of December the pitted material had on the average 
parted with 13:25 per cent. of total nitrogen, whereas the loss in the manure in 
heaps averaged 25°3 per cent. When the behaviour of the ammoniacal nitrogen 
was investigated it was found that the loss was 35°73 per cent. in the pits and 
82°5 per cent. in the heaps. The loss, therefore, is greatest in that part of the 
nitrogen which is the most active and the most valuable. 
In another series of experiments by the same investigators the manure was all 
placed in pits, but in one case it was spread equally and trodden down, while the 
escape of liquids was prevented. In the other case the manure was simply thrown 
loosely and irregularly into the pit without spreading or treading, the surface 
being left uneven and therefore much exposed to the air, while the liquids were 
allowed to drain away. After lying for twenty-two weeks the loss of nitrogen 
was 15:76 per cent. in the pit containing the carefully treated manure, whereas in 
the other pit the loss amounted to 34°58 per cent. 
Pfeiffer in a series of experiments proved that much of the nitrogen that 
disappears from manure is lost before the manure is transferred from the stall to 
the dungstead. He is strongly of opinion that stalls, boxes, and the like, should 
either be cleaned out twice daily, or, if the construction admits, the manure 
should be left to accumulate till it is some feet in depth, as in the system of 
management that prevails in cattle-courts and yards in this country. 
The general conclusion arrived at, and clearly expressed by Pfeiffer, is that 
excessive loss in manure can be best avoided by storing it ina deep mass ina 
water-tight dungstead placed in a well-shaded situation, in which the material is 
firmly compressed. The necessary compression can be secured in various ways, 
perhaps most conveniently and effectively by means of the treading of cattle. The 
use of a considerable proportion of moss-litter is strongly recommended. This 
substance not only absorbs and retains the liquids, but, being acid, it fixes 
ammonia. In the absence of moss-litter, loamy soil rich in humus will prove a 
useful substitute. 
The Chemical Fixation of Atmospheric Nitrogen, 
It has for long been the dream of chemists to discover, or welcome the discovery, 
of a chemical process, capable of industrial application, by which the nitrogen of 
the air could be made available to replace or to supplement our rather limited 
supplies of nitrogenous manures. In his Presidential Address, Sir William 
Crookes had something to say on this fascinating subject, and looked hopefully to 
electricity to solve the problem. He pointed out that with current costing one- 
third of a penny per Board of Trade unit a ton of nitrate of soda could be produced 
for 267. ; while ata cost of one-seventeenth of a penny per unit—a rate possible when 
large natural sources of power, like Niagara, are available—the cost of such artificial 
nitrate of soda need not be more than 5/, per ton.? 
Dr. von Lepel, in giving an account of recent work on this subject to the 
1 Crookes, The Wheat Problem, p. 47. 
