1 6 Reynolds and Moorby, Equivalent of Heat. 



At first the difficulties looked formidable, but on 

 trying by gradually restricting the supply of water to the 

 brake when absorbing 60 H.P., and finding that it ran quite 

 steadily with its automatic adjustment, till the temperature 

 of the effluent water was within 3° or 4° of 212°, he 

 further considered the matter, and formed preliminary 

 designs for what seemed to be the most essential appli- 

 ances to meet the altered circumstances. These involved : 



(i) An artificial atmosphere; or a means of main- 

 taining a steady pressure in the air passages of the brake 

 of about four-thirds of an atmosphere. 



(2) A circulating pump and a water cooler, by which 

 the entering water, some 30 pounds a minute, could be 

 forced through the cooler into the brake at a temperature 

 of 32^, having been cooled by ice from the temperature of 

 the town's main. 



(3) A condenser by which the effluent water leaving 

 the brake at 2 12*^ F., might be cooled down to atmospheric 

 temperature before being discharged into the atmosphere 

 and weighed. 



(4) Such alteration in the manner of supporting the 

 brake on the shaft, as would prevent excess of leakage 

 from the bushes in consequence of the greater pressure of 

 air in the brake ; since not only would the leaks be 

 increased, but, when the rise of temperature of the water 

 was increased to 180^, the quantity for any power would 

 be diminished to one-sixth of what it would be for 30^, so 

 that any leakage would have six times the relative 

 importance. 



(5) Some means which would afford assurance of the 

 elimination of the radiation and conduction, as with a rise 

 of 140'^Fahr. above that of the laboratory, these would 

 probably amount to two or three per cent of the total heat. 



(6) Scales for the greater facility and accuracy in 

 weighing the water, with a switch actuated by the counter. 



