1020s Prof. Treadwell’s Improvements in Cannon. 
seded by the Jater one. That is used in forming the hoops of 
the Parrott gun, and in most of the British guns. d the best 
gun which could now be made, as experience has shown, would 
be composed of a barrel of cast-iron or steel, inclosed and com- 
pressed by a cylinder of coil. 
e need not discuss the question of priority of invention be- 
tween Mr. Treadwell and others, competitors for a share in the 
honor of producing the modern cannon. His independence of 
each and all of them has never been called in question. Nor 
principal result of this third investigation, proceeds to show, 
that, to attain with effect the end sought for by hooping a cast» 
iron gun, it is necessary to harden the wrought-iron hoop by 
cold hammering and severe stretching before placing it upon the 
gun-body. He computes, that, by this simple means, a hoope 
gun may be made more than twice as strong as those which have 
been constructed by Blakely and Parrott, the materials being in 
both cases the same. 
gz q 
restored (rifling excepted) from Mr. Treadwell’s papers alone. 
And now, Mr. Treadwell, in delivering into your hands this 
beautiful gold medal and its silver duplicate, I have much pleas- a 
