ARTIFICIAL REFRIGERATION AND ICE MAKING. LXVII. 
Scale 56 mm = 1Kg C 
1” = 64 Ibs. 
Gauge (—~ pili 
ee 
Cauvge 
ze Atm tive 
give the maximum of tightness as the point on the diagram 
showing the end of the suction stroke is very sharp, the same 
being the case at the end of the compression stroke. The 
Suction and delivery valve springs do not offer much resistance 
to the opening of the valve, where the valves are anything like 
tight a greater resistance to the opening of the valve would 
be exercised by the film of oil which would be between the valve’s 
Surface and its seat. 
With regard to No. 2, the results of some experiments 
made on two twenty-four ton Linde Compressors to ascertain 
the power required to overcome the friction in the stuffing 
box, shewed that with a condenser pressure of 180 Ibs. per square 
inch, the power required was somewhat less than one quarter 
indicated horse power the gland remaining perfectly tight and 
Cool. It is not absolutely necessary to have a special pump for 
_ Pumping the oil through the lantern bush, as the oil is not under 
Pressure. A sight drop lubricator is frequently used. As regards — 
oil getting into the system of a plant, this is practically prevented 
by the insertion of an oil collector ; a little oil in the compressor 
is an advantage as it ensures the tightness of the valves and 
_ piston rings. 
Dealing with No. 4, the general design and construction of the 
“Machine, Mr. Statham said that this point has received the Linde 
~ British Refrigeration Co’s. special attention, and as a result of 
