AND ITS APPLICATION TO MR, B. TOWER’S EXPERIMENTS. 
215 
The moments of friction in inches and lbs,, divided by 24 X R, are called the nominal 
friction per square inch. 
These nominal loads, and nominal frictions, with the number of revolutions from 
100 to 450, at which they were taken, are arranged in tables for each kind of oil used, 
and also for the same oil at different temperatures of the bath. 
All the tables relative to the oil bath in the first report refer to the same brass and 
journal. And with this brass, to be here called No. 1, no definite measurements of 
the actual pressure were made. 
The second report contains the account of the pressure measurements, but it is to 
be noticed that these were made with a new brass, here called No. 2, and that the 
only friction measurements recorded with this brass are three made at velocities five 
times less than the smallest velocity used in the case of brass No. 1. 
It thus happens that while by the application of the foregoing theory to the friction 
experiments on brass No. 1 a value is obtained for a, the difference in radii of brass 
No. 1 and the journal; and from the pressure experiments on brass No. 2 a value is 
obtained for a in the case of brass No. 2 ; since these are different brasses there is no 
means of checking the one estimate against the other. 
The following tables extracted from Mr. Tower’s reports are those to which 
reference has chiefly to be made. 
The first of these extracts is a portion of Table I. in Mr. Tower’s first report; this 
related to olive oil, but corresponds very closely with the results for lard oil also, 
although not quite so close for mineral oil. 
The second extract is Table IX. in the first report; this shows the effect of 
temperature on the friction of the journal with lard oil. 
The third extract is from the second report, being Table XII., representing the oil 
pressure at different parts of the bearing as measured with brass No, 2. 
From Table I. (Mr. Tower’s 1st Report, Brass No. 1.) Bath of Olive Oil. Tempera¬ 
ture, 90 deg. Falir., 4-in. journal, 6-in. long. Chord of arc of contacts 3‘92 in. 
load 
quare 
Total 
vided 
3. 
Nominal friction per square inch of bearing. 
r—i y 
c3 £ . X 
C ~ -li 
100 rev. 
150 rev. 
200 rev. 
250 rev. 
300 rev. 
350 rev. 
400 rev. 
450 rev. 
a j § § >> 
105 ft. 
157 ft. 
209 ft. 
262 ft. 
314 ft, 
360 ft. 
419 ft. 
471 ft. 
£ 
per min. 
per min. 
per min. 
per min. 
per min. 
per min. 
per min. 
per min. 
520 
•416 
•520 
•624 
•675 
•728 
•779 
•883 
468 
, , 
•514 
•607 
•654 
•701 
•794 
•841 
•935 
415 
•498 
■580 
•622 
•705 
•787 
•870 
•995 
363 
•472 
•580 
•616 
■689 
•725 
■798 
•907 
310 
•464 
•526 
•588 
‘650 
•680 
•742 
•835 
258 
•361 
•438 
•515 
•592 
•644 
•669 
•747 
•798 
205 
•368 
•43 
•512 
•572 
•613 
•675 
•736 
•818 
153 
•351 
■458 
•535 
■611 
•672 
•718 
•764 
•871 
100 
1 
■36 
•45 
- 555 
•63 
•69 
•77 
•82 
•89 
