I50 STORRS AGRICULTURAL EXPERIMENT STATION. 
by Stohmann, which consists of tubes and gas cocks so arranged 
that either cylinder can be connected with the bomb or discon- 
nected without trouble. A manometer is joined to the tube 
leading to the bomb. One cylinder alone is used for charging 
until the pressure falls below 20 atmospheres. ‘Thereafter, in 
charging, the oxygen is allowed to run from this cylinder into the 
bomb until the pressure is the same in both; the connection then 
is shut off and the other cylinder, in which the pressure is higher, 
is connected with the bomb and the charging up to 20 atmos- 
pheres is completed. In this way the oxygen in the first cylinder 
can be used until the pressure is reduced to one atmosphere. 
The cylinder is then sent away to be refilled. We find it con- 
venient to have three cylinders and are thus never without at 
least one with sufficient pressure for charging. 
The results of our experience thus far may be briefly summarized. 
1. Asto apparatus. The bombs we have had made at home 
as above described seem to promise better than anything we 
should be able to obtain from European makers. The strongest 
and best gun steel is to be had in this country and the work- 
manship is better than anything we have seen in apparatus of. 
the kind made in France or Germany. We are not yet certain 
that the platinum lining can be more advantageously provided | 
here than in Germany though that now seems probable. We 
are attempting to find a way to put on the lining by electro- 
plating, using another metal between the steel and the platinum. 
If this proves successful it will materially lessen the cost; if it 
does not, a lining of sheet platinum can be used. We hope that 
it will prove feasible to use some cheaper metal than platinum 
for lining the steel bomb or to use some non-corrosive metal in 
the place of the steel for the whole bomb and thus avoid the 
lining entirely, but are not yet able to speak of the prospect of 
success. The accessory apparatus is simple and easily obtained. 
There is therefore no doubt that an accurate, convenient, rea- 
sonably durable and inexpensive bomb calorimeter with the 
accessory apparatus can be made available to those who have 
occasion to use it. . 
2. As to method. To determine the thermal equivalent of 
the apparatus is a somewhat difficult and time-consuming opera- 
tion, but when that is done and the schedules for noting the 
observations and the formulas for calculating the results are 
made out and the method of manipulation is well in hand, the 


