288 TOWERS AND TASKS FOR WATER- WORKS. 



ceived from the manufacturer of this machine, " not a single 

 rivet had to be cut out or caulked, a most exceptional record 

 which has not been equalled by any other machine. They 

 drove 800 to 1200 rivets per day, depending on size. They 

 tell me the cost of driving by machine was less than half that 

 of driving by hand. Allowing three men and a boy on ma- 

 chine, at $9.00 per day and $4.50 for cost of running air- 

 compressor and fuel, or $13.50 per day for crew, this makes 

 a cost of about one to one and a half cents per rivet." 



A quotation from a communication to the Engineering 

 Nezvs from Mr. Freeman C. Coffin, M. Am. Soc. C. E., will 

 be used in concluding this subject, and is as follows: " The 

 rivets should be driven by steam or hydraulic power. This 

 may seem radical, but I do not think so. I see no real rea- 

 son why it could not be done with the suitable appliances. 

 If field-riveting can be clone by power in any structure, a 

 stand-pipe is the best form, as there are continuous rows of 

 rivets of about the same diameter, and the only especial form 

 of appliance would be the yoke of the riveter, which would 

 need to straddle a 5-foot plate. I do not believe that this is 

 impracticable. I think it must hurt the feelings of any engi- 

 neer to see two men with heavy sledges pounding away at 

 a cool rivet, endeavoring to form a head on it. The usual 

 result is a very thin, flat head, as the rivets are used as short 

 as possible in order not to cause too much trouble if they 

 happen to get cold before they are finished." 



