Page:Journal of a Voyage to Greenland, in the Year 1821.djvu/259

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APPENDIX.
205

greatest impulse, and to destroy that friction which so much diminishes the force and accuracy of flight of the harpoons now in use. On the discharge, the harpoon is disengaged from the wooden cap, by the splitting of the latter.

To cause the withers to extend beyond the orifice made by the harpoon, and to ensure their catching, springs were added as here represented.

Neither the lock of the gun mentioned in the certificate, nor the gun itself, possessed any originality, (and only a simple means was used to prevent the gun from going off by accident, by a cover over the hammer); it exploded the charge by percussion, giving a powerful stroke upon well primed and dried fulminating composition, in copper caps, which effectually defied the elements to prevent the use of the instrument: much attention is requisite in employing this composition, but when that attention is scrupulously paid, it will never fail; in confirmation, I have exploded more than a hundred primings in succession without one having missed.

The gun used in the experiments was two inches in diameter, in the bore, and fourteen inches in length, having at the bottom a chamber and antechamber for the more immediate manner of exploding the charge, and producing the greatest velocity.

The preceding remarks on the failure of late years, in taking whales with the certificate I did myself the honour of sending to Captain Scoresby, as a gentleman of great experience on the subject, and, in return, had the pleasure