SHOP-PRACTICE AND ERECTION. 287 



sampko of heavy plates riveted by both hand- and machine- 

 work were split with a saw, and the rivets and holes shown 

 in cross-section. All machine-driven rivets completely filled 

 the rivet-holes, while the hand-work was seen to be very 

 irregular. In his work entitled " Iron Highway Bridges," 

 and in connection with suggestions for riveting, the follow- 

 ing is given by Mr. Alfred P. Boiler, M. Am. Soc. C. E.: 

 " Power-riveting is so superior in all respects to hand-rivet- 

 ing that a higher unit of strain, by probably 10 per cent., can 

 be used under the former system; so that if it is considered 

 proper to strain hand-rivet work up to 13,500 Ibs. per square 

 inch, work riveted up by steam or hydraulic power can be 

 safely proportioned on a basis of 15,000 Ibs. per square inch." 



So clearly is the superiority of power-riveting, that it is 

 specified almost exclusively for boiler-work, bridge-work, and 

 in fact for almost all shop-work, but its use in the field is com- 

 paratively limited and of recent date. In this connection, the 

 Engineering News for May, 1895, publishes a description of 

 a stand-pipe erected at St. Barnard, by L. Schreiber & Sons 

 Co., of Cincinnati, Ohio, who used for the field-work a pneu- 

 matic riveting-machine, suspended from a 'hoist by the 

 arm of a crane with mast in the centre of the shell. In re- 

 sponse to an inquiry as to this work and as to the cost and 

 efficiency of power field-riveting in general, Messrs. Schrei- 

 ber & Sons Co. reply " that we have found pneumatic rivet- 

 ing much better than hand-work, especially so if the machin- 

 ery is of the proper kind. We do this work under very high 

 pressure and hardly believe (owing to the fact that the ma- 

 chinery required for this work is very heavy) that there is a 

 great saving over hand-riveting. However, there is a little 

 in favor of the machine-riveting." 



The Logan Iron Works, contractors for a stand-pipe at 

 College Point, L. I., used a pneumatic riveting-machine in 

 driving some 75,000 rivets. According to information re- 



