Twentieth century hand-book for steam engineers and electricians with questions and answers; a practical non-technical treatise .. (1913)
Swingle, Calvin Franklin, 1846- [from old catalog] · Chicago, F. J. Drake & company · leaf 507
., wheresprings of high tension (80 to 125 lbs.) are required. The lines on such scales are so close together, and thefigures are so small, that it is very difficult to distinguishthem. However, there are other and more simple methodsthat can be used, and the results are just as accurate. 494 Steam… … A Fig. 178
