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PROFESSOR OSBORNE REYNOLDS AND MR. J. H. SMITH ON A 
the testing machine and engine were attended to, the cocks being adjusted to give 
the necessary flow for each hearing ; the large oil vessels on the wall were filled up ; 
the rope was placed on a suitable step of speed pulley, and the movable pulley was 
adjusted to give the requisite tension for driving; a specimen was inserted in the 
manner previously described ; the counter reading was taken ; the water inlet cock 
connected to the hydraulic brake was adjusted so as to give the necessary flow of 
water through the brake ; and the apparatus was then ready for the carrying-out of 
a test. 
Having decided upon the particular speed at which the machine was to run, the 
speed of the engine to obtain this was found from the tabulated results of a series of 
experiments previously made ; the flow of water from the engine brake was 
regulated (see p. 275) by means of the water outlet valve, attached to the spindle of 
which was a long arm, which enabled one to delicately adjust the valve opening (so 
as to bring the engine to the chosen speed); the machine was started after the 
engine had been working steadily for a few minutes. 
At the commencement of a test the author usually watched the speed indicator 
attached to the machine ; the engine attendant watched the engine speed indicator 
and adjusted the outlet valve of the brake if necessary. The speed of the machine 
gradually rose; the time taken to rise to the required speed varied from 60 to 100 
seconds when the machine was started first thing in the morning, but the speed was 
attained in about 20 seconds when the machine had been running for a short time 
before beginning the test. 
It was very important to carefully watch the speed indicator columns on starting, 
as the speed of the engine had to be reduced always one or two revolutions per 
minute in the first few minutes of the run, which appeared to be the time necessary 
to obtain steady lubrication of the bearings ; moreover, a great amount of trouble 
was saved when the brake had been carefully adjusted at the commencement of the 
test, for in many experiments, when tins adjustment had been made, it was found 
unnecessary to touch the outlet cock for periods of 30 minutes or even longer. On 
arriving at the steady speed, it was only necessary to watch the speed indicator on 
the engine, since the fluctuations of the two speed indicators were found to agree, but 
still the indicator connected to the machine was examined about every 10 minutes. 
Throughout the test the boiler was attended to, so as to keep the pressure as 
nearly constant as possible. 
The time at which the machine attained the required speed was taken by means of 
a watch ; and when the speed of the engine had become steady, the counter on the 
testing machine was pushed home, and the number of revolutions taken for from 
10 to 100 minutes, according to the length of the time taken for the test; after one 
minute’s interval, during which the counter reading was taken, the counter was 
again pushed home, and so on throughout the test. 
The time at which the specimen broke was taken, and the total time from 
