









| 15214 | 14733 | 4747 base ) 
| | | 
wee | 

The results from (5) are taken from Dunkerley’s paper. 
The values of c// really differed slightly for the two pulleys ; 
the values given in the headings to the Table are the means 
for the two cases. 
Tt will be seen that except in the first instance, where the 
pulley was only an inch from a support, the simple formula 
(6) differs but little from (5). The difference for the larger 
values of c/l is so small that the improvement obtained when 
(10) is substituted for (6) is hardly worth considering. 
§ 24. Table IV. gives particulars of the critical number of 
revolutions per minute of an unloaded shaft as observed and 
calculated by Dunkerley, and as calculated from several of 
the other equations advanced above. 
TasLe [V.—Unloaded overhanging Shaft, critical speeds. 




Transverse Vibrations of Rotating Shafts. Spal 
TasieE III. 
Bg roe {|) 2 207 3°66 499 | 7:66- 10°32 
“ida | 3066" | 59-10 0 =| 2666 | 2400 21-33" 
/ ie Fiat J | Fi | 
Pulley I | II. | “eal th wel ees els Foe ieee Tee Lhe |i.) 0, 
Formula . | | | | | 
2 ae | 16390 | 13816 | 4808 3353 8318 2277 2428 16481572 1056 1162 782 
| | | | ‘ 
ee... |12014| 8020} 4603 3157 | 8256 , 2209 2398}1617 1562 |1051| 1161 | 779 
/ | ' | 
| | | | 
Maps... | 3307 | 2275 | | 




! Caleulated values from | 
i | Observed . | 
ote value. (1) by | | 
Dunkeder | ©) \A4)@i=0)! (5) |@5)at=0). 
1/10 . 1309 1301 1351 | 
1/7 1435 1397 | 1450 | 
1/5 1472 1516 1571 1574 | 
1/3 1606 1704 2013 \) 1747 
| 1/2 1558 1606 3825 i. Teoy | 
i 1002 1031 1058 1046 

The values calculated by Dunkerley for small values of ¢/l 
are apparently affected by the error referred to in (a) ; if 
this were corrected his values should practically coincide 
| 

