256 MR. J. C. DYER ON THE ORIGIN OF 



any nails of less than about one inch in lengthy so that 

 they could not be employed for making tacks^ or very 

 small nails^ although this branch of the trade offered the 

 greater chance of saving by self-acting machinery. It 

 thus became an object of importance to make such changes 

 in the patent machines as would fit them for making the 

 tacks and small nails as well as the larger ones. 



To ascertain whether this could be effected, I began by 

 tracing the successive movements to find where the de- 

 fective action took place, and its cause. After the nails 

 were cut, they were carried down to the heading-dies below 

 the cutter so that the head ends would stand out from the 

 gripping dies when the cutter rose out of the way of the 

 heading die ; but before the gripping dies closed upon the 

 nail, a small presser advanced to hold the nail near the 

 point, and prevent its falling out of the line of the dies ; 

 but in the case of tacks or small nails, the greater weight 

 of the other end caused it to fall and spoil the work. It 

 therefore became necessary to have the nail held at the 

 head end, in lieu of the point, when thus brought between 

 the gripping dies, and for removing the holder out of the way 

 to admit the advance of the heading die. To effect this 

 purpose I made the bed-cutter in two pieces to act together 

 in one line for cutting, and the portion cutting the head 

 end, after serving to support the nail as above, to slide 

 back out of the way of the heading, and by this simple 

 contrivance, of dividing the bed-cutter into two parts, one 

 fixed, the other moveable, the machine was quite as well 

 adapted for making tacks and minute nails as it was before 

 for making large ones; and this simple change rendered 

 the patent nail-making a complete success ; and by far the 

 larger profits accruing from their use came from the ma- 

 chines to which this slight change was applied. 



The course of movements of the several machines and 

 their rate of working were exhibited by means of wooden 



