322 Mr. Mallet on the Physical Conditions 



to make it appear one mass. The longitudinal bars are parallel in thickness throughout, 

 and meet edee to edge, but their exterior and interior arc slightly taper; the chase, there- 

 fore, is not cylindrical, but conical, as is also the chamber; the caliber at the muzzle being 

 20 inches, and that at the bottom, close to the chamber, 20J inches. The effect of this was 

 to give a much larger windage at the commencement of motion of the stone ball than at 

 its leaving the piece, -which, with very slow-burning powder, must have greatly eased the 

 strain upon the gun, without very materially reducing the velocity and range. 



This advantage may have been intentional ; but the primary object of this taper was, 

 no doubt, to facilitate the getting on of the external rings when red hot. It is obviously 

 so formed by design, and not by accident or error of workmanship ; and, being a uniform 

 taper, could not have resulted from swelling produced by the strain of explosion acting most 

 severely towards the breech. 



The following are the principal dimensions : — 



Feet Inches. 



Total length, 13 6 



External diameter of muzzle, 24| 



External diameter of breech, 27 



Greatest external diameter 2 4| 



Length of chase, interior, 8 9J 



Caliber at muzzle, 20 



Caliber at breech, 20J 



Longitudinal bars, twenty-five, each | in. thick x 2^ in. nearly. 

 External rings, average width, 3^ ins. ,, „ 



„ „ radial thickness, from 3f in. to i in. 



Length of chamber, interior, 3 9 



Diameter at mouth, 9| 



Diameter at breech, lOJ 



Thickness of wall of chamber, minimum, 6 



Thickness of breech in line of axis, 5| 



Vent, distant from exterior of breech in line of axis, 9J 



The vent is much enlarged (though still round), owing to corrosion. 



The iron of the gun has been commonly supposed Swedish ; it is much more probable, 

 however, that it is of iron faggoted up by hand-hammers from small bars of native-made 

 chaicoal-iron, from the ancient forges of Cumberland or other parts of the Border country. 

 Iron thus wrought is perfectly undistinguishable from Swedish, though usually a little 

 solter. 



The following is the history and .tradition respecting this gun, taken from " The 

 Statistical Account of Scotland :" — 



