W.W. Greener, "The Gun and Its Development" page 142
TOP-LEVER ACTIONS AND OTHERS.
There are two distinct types of top-levermechanisms in one the lever swings upon a horizontal pivot on the standing breech, and is either raised or is depressed to withdraw the holding-down bolt and open the gun. This type is not generally used. In the other the lever turns upon a vertical pivot, and actuates various mechanisms, used to bolt the breech-action body and the barrels together.
The first top-lever mechanism is said to be that of a Birmingham gunsmith named Matthews. His production was a crude one, but the principle was improved upon and adopted a better form of it was introduced by Westley Richards about 1860, and "was applied to pin-fire guns. The chief advantages of the breech action lever being placed upon the top of the gun are: first, it is possible to carry the gun in any position without catching or displacing the lever; second, the shooter can at once detect whether or not the action is securely fastened, the position of the lever being noticeable as the gun is raised to the shoulder for firing; third, it is easier to manipulate than any other, and, length for length, allows of greater leverage than if placed elsewhere; the power the manipulator has to control the lever fixed in this position is very great, it being possible with even a short top-lever to raise both locks to full-cock as well as withdraw the holding-down bolts and overcome the weight of the spring which drives them home. Another advantage is that the hand, after firing the gun, can work the lever without losing its grip of the stock. A variety of bolts have been used with the top-lever, the most common being the double holding-down bolt shown in the illustrations of the "Top-lever Gun with Back-action Locks." Single, treble, and even quadruple grip-bolts have been made. The double bolt is preferable, as the single bolt, being short, Top-lever Gun with Back-action Locks.
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In addition to the levers already described, the holding-down bolts have been actuated by other devices, or by modifications of one or other of the levers noticed. A favourite at one time was the "Purdey", a short lever in front of the trigger-guard, the bow of which was pierced to allow the thumb to reach the lever and force it forward. Other levers in this position, instead of being pushed forward, or from the gun, to open the mechanism, were pressed towards it—a plan favoured by "Stonehenge", and still in use on a modern French gun, and but recently discarded by a well-known firm of manufacturers in America. In some cases the lever, instead of being moved by thumb or finger, is worked by the hand, as in the "comb-lever", which extends from the breech to the comb of the gun-stock, and is depressed to withdraw the holding-down bolts.
Pete
