between which and the body of the screw the press 

 lever was thrust; this latter was at that time coming 

 into use, being less liable to break than the lantern 

 head. The large diameter of the trundle enabled 

 the pressman to use it as a hand wheel to run the 

 screw down and give considerable pressure before 

 using the lever and windlass. This class of press 

 screws were made of cast iron, and rarely exceeded 

 6 inches diameter. They were cast at the foundry 

 of Rush & Muhlenberg, 46 Philadelphia, and turned 

 ready for cutting the screw thread on a lathe got up 

 by Cadwallader and Oliver Evans. This lathe was 

 the nearest approach to our present engine lathe 

 that I can recollect in Philadelphia at that time. It 

 was a wooden shear lathe with cast-iron slides for 

 the poppet head and tool-carrying rest, which rest 

 was moved by hand wheel with crank-handle operat- 

 ing a pinion attached to the rest and working into a 

 fixed cog-rack on the front shear. 



Screws for tobacco and other small presses were of 

 wrought iron and varied from about 2% to 4 inches 

 diameter, and in every case made of piled charcoal 

 iron, nine square bars being used to each pile; the 

 object being to have a solid center bar. These pile 

 rods of hammered iron of the required size were made 

 at some one or other of the Pennsylvania charcoal 

 forges. The piles were heated in a hollow fire of 

 imported bituminous coal, at that time known as 

 Liverpool coal, or an open hearth by a blast from 

 a couple of wooden tubs about 4 feet diameter, their 

 pistons alternating by a wooden walking beam, 

 worked through a connecting rod by a crank on the 

 end of the shaft of a breast water-wheel. There was a 

 third tub with weighted piston to regulate the blast. 



The forging was done under a couple of trip 

 hammers, one for roughing, the other for swedging, 

 driven by an undershot watcrwheel, with tappet 

 wheels on its shaft, regulated in their diameters and 

 number of tappets so as to give twice the number of 

 blows to the swedging hammer. The heads of the 

 screws with lever holes at right angles and one above 

 the other were shaped and finished on an ordinary 

 anvil, with hand hammer and sledges. On the end 

 of the screw bolt was forged a square tit not over 

 half an inch long and of such a size as to come within 



*» An outgrowth of the Oliver Evans Mars Works. Rush 

 and Muhlenberg, both sons-in-law of Evans, established their 

 foundry and machine works in 1816 on the site of the present 

 U.S. Mint, on Spring Garden Street west of Broad. (Greville 

 Bathe and Dorothy Bathe, Oliver Evans, Philadelphia, His- 

 torical Society of Pennsylvania, 1935, p. 232 and passim.) 



the diameter of the bottom of the screw-thread when 

 cut; the object of this tit will be explained further on. 



The turning and screw-cutting lathes were of the 

 most primitive construction. The bed or shears were 

 two white oak timbers about 12 or 14 inches square, 

 about 6 inches apart, securely bolted to stone founda- 

 tions. The lathe head was two pieces of timber the 

 same size as the shears boxed into and crossing them, 

 with a space of about a foot between them; into 

 these the boxes that carried the mandrel were let, 

 the overhanging center-carrying end of the mandrel 

 was square on which the face-plate, or rather cross, 

 was keyed; the entire end thrust was taken by the 

 boxes by collars on the journals, the back end of the 

 mandrel was also square and overhung sufficiently 

 to carry a spur wheel about 4 feet diameter, with 

 5- or 6-inch face with wooden cogs in which a trundle 

 pinion worked as the driver; part of the pinion shaft 

 was square, on which part slid a ratchet clutch, 

 which fastened by a corresponding ratchet on the 

 iron hub of a loose, deeply grooved wooden pulley, 

 driven by a twisted rope belt made of raw hide; 

 the ratchet clutch was so arranged as to be shoved 

 into gear or disengaged by a foot treadle in front of 

 the lathe shears, giving the operator instant com- 

 mand both in starting and stopping. 



The back or poppet head was similar to the main 

 head only differing in its timbers not being so heavy 

 and being set closer together, and on their under 

 sides connected by a piece of wood fitting and pro- 

 jecting into the space between the shears, to act as a 

 guide for the back head; the mandrel was square 

 let into and screwed on its angle to the head blocks, 

 the end of this back mandrel carrying the center 

 overhung the blocks about 3 inches and was ac- 

 curately turned to a collar, which, besides its especial 

 object, prevented the mandrel sliding back on the 

 head blocks. There was no arrangement to move 

 this mandrel forwards or back; the head was clamped 

 to the shears in the usual way, and the center held 

 to its work by wooden wedges driven between the 

 head block and a piece of scantling that lay across 

 the shears, held in its place by iron pins in holes 

 in the top of the shears. There were rows of these 

 auger holes about \% inches in diameter and 6 or 8 

 inches apart. The tool rest or rather rests, for they 

 were the lengths suited to the bolts to be turned and 

 screws to be cut, were flat bars of wrought iron se- 

 cured to wooden rests; the only way to regulate the 

 height of these long rests was by the thickness of the 

 wooden supports. Close to the edge next the work of 



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