Having thus been the means of introducing improved cannon locks into the naval service, and strongly convinced of the very great importance of applying locks to all land service artillery, whether field, siege or garrison, the author addressed to the Master General, and Board of Ordnance, a recommendation to that effect in the same paper in which he proposed the improved doubleflinted locks for general adoption in the navy. But the Board of Ordnance not having, as the reader will perceive, in their letter dated January 16, 1818, come to any decision on that proposition, in conveying to the author their approval of the other, he resolved to endeavour to procure support in the prosecution of his plan by consulting officers of greater experience and authority, and, in the event of their judgment coinciding with his, to press the subject on the reconsideration of the Board with all the energy in his power. He accordingly transmitted a copy of his proposition to his gallant friend and associate the late Sir Alexander Dickson, an officer eminently qualified by his great experience, knowledge, and talent to pronounce authoritatively upon all matters connected with artillery service, and received in reply the letter printed in the subjoined note."

"Valenciennes, 20th April, 1818.

MY DEAR SIR HOWARD,-Having fully considered the matter, I feel much pleasure, in compliance with your wish, in being able to state that your proals for the more extended use of locks coincide in the most essential points wt. n.y own ideas on the subject.

The use of locks with heavy ordnance, particularly in the operations of a se, presents very great advantages; for by the employment of slow-match only the fire is frequently retarded, and nothing can be more dangerous than azited portfires in a battery. I have seen several very shocking accidents occasioned by the use of them, owing to the want of presence of mind of the

er having the portfire lighted in his hand at the moment of a shell falling Lear him. In the sieges I have directed I have ever prevented, as much as in nower, the use of portfires; but Ciudad Rodrigo was the only operation in

I was fully successful in this respect; and it was to the help of about Liten or twenty naval gun-locks, in addition to the slow-match used, that I was indebted for the vigorous fire kept up in that attack. I trust in future, therefore, that in all siege equipments each piece of ordnance will be supplied with a lock, the use of which, under every circumstance, except in heavy rain, would supersede the portfire, which in the very confined situation of a land battery, and where much powder is in circulation, is so dangerous.

"In the operation of defence, also, the same arguments, in a great degree,

Supported by that distinguished officer, the author's proposition received favourable consideration, and would then have been carried into effect had not financial and other considerations rendered it inexpedient to provide forthwith the necessary supply of locks. Thus the measure remained in a state of suspension, until at length the discovery of the percussion principle, and its application to fowling pieces, indicated that all flint-locks would ere long be superseded by percussion locks and tubes. This having been effected, the author, in 1851, reverted to his proposition of 1817-under a still stronger conviction of the greater importance, or it may well be said, of the more pressing necessity of this measure in the present improved state of artillery science and gunnery practice, than when he first wrote. This equipment is so forcibly urged in Sir Alexander Dickson's letter with respect to field and siege artillery, that nothing need, or could be said, to add to the weight of that testimony, whilst much that has been stated in the course of this work on the vast importance of the percussion lock and tube, in firing at ships in motion, applies strongly to the necessity of providing these means of procuring a more instantaneous explosion to all guns in coast batteries, which, though at rest themselves, will have to fire at moving objects,-ships

hold good in favour of locks; and they are truly valuable in coast batteries, and in all night firing.

"With respect to their being applied to artillery in the field, I am convinced that, with a tube such as you describe, locks would be of infinite service with field guns in ordinary duties, such as reviews, firing exercises, and salutes, and in all real service, when not too closely engaged. The effect of the lock being sufficiently certain in these situations, the saving of portfires would be great, and there would be far less risk when in action amongst ripe corn, dry grass in villages, or amongst houses; for the setting fire to a country more generally arises from cutting the portfire than from the discharge.

"In concluding, I have to observe that I do not mean to resolve the question merely into one of economy, as I deem it on most occasions an effectual simplification of manœuvre by saving the trouble of continually lighting and cutting portfires, at the same time affording the means of firing with celerity at moving objects.

"I remain, my dear Sir Howard, &c. &c.
(Signed)
"A. DICKSON.

"Colonel Sir Howard Douglas, Bart.
&c.
&c."

Having thus been the means of introducing improved cannon locks into the naval service, and strongly convinced of the very great importance of applying locks to all land service artillery, whether field, siege or garrison, the author addressed to the Master General, and Board of Ordnance, a recommendation to that effect in the same paper in which he proposed the improved doubleflinted locks for general adoption in the navy. But the Board of Ordnance not having, as the reader will perceive, in their letter dated January 16, 1818, come to any decision on that proposition, in conveying to the author their approval of the other, he resolved to endeavour to procure support in the prosecution of his plan by consulting officers of greater experience and authority, and, in the event of their judgment coinciding with his, to press the subject on the reconsideration of the Board with all the energy in his power. accordingly transmitted a copy of his proposition to his gallant friend and associate the late Sir Alexander Dickson, an officer eminently qualified by his great experience, knowledge, and talent to pronounce authoritatively upon all matters connected with artillery service, and received in reply the letter printed in the subjoined note."

He

"MY DEAR SIR HOWARD,-Having fully considered the matter, I feel much pleasure, in compliance with your wish, in being able to state that your proposals for the more extended use of locks coincide in the most essential points with my own ideas on the subject.

"The use of locks with heavy ordnance, particularly in the operations of a siege, presents very great advantages; for by the employment of slow-match only the fire is frequently retarded, and nothing can be more dangerous than lighted portfires in a battery. I have seen several very shocking accidents occasioned by the use of them, owing to the want of presence of mind of the gunner having the portfire lighted in his hand at the moment of a shell falling near him. In the sieges I have directed I have ever prevented, as much as in my power, the use of portfires; but Ciudad Rodrigo was the only operation in which I was fully successful in this respect; and it was to the help of about sixteen or twenty naval gun-locks, in addition to the slow-match used, that I was indebted for the vigorous fire kept up in that attack. I trust in future, therefore, that in all siege equipments each piece of ordnance will be supplied with a lock, the use of which, under every circumstance, except in heavy rain, would supersede the portfire, which in the very confined situation of a land battery, and where much powder is in circulation, is so dangerous.

"In the operation of defence, also, the same arguments, in a great degree,

was, however, modified and improved so as to be stronger, and better suited to the locks in use in this country, by Colonel Dundas, Inspector of Artillery, to whom the service is so much indebted for his management of that important department, to which he was appointed in 1839.

The hammer A (fig. 35), which is of wrought iron

Fig. 35.

Α'

American Lock, improved.

of good quality, is fixed into a block or joint of gun-metal by means of a pin a, and a slot is made in the hammer to admit of a back motion. The hammer falls by its own gravity upon the vent

on the lanyard BC being pulled, when, being liberated from the larger part of the slot in which it is made to turn, it instantly shifts or passes away by the continued action of the lanyard, which pulls it from its first position directly over the vent, as shown by the black lines at A'in the figure. The weight of the hammer is 3 lbs. 374. This lock, though extremely ingenious and advantageous from the simplicity of the contrivance by which the hammer, having performed its office, is drawn back from the top of the vent by the same force which causes it to strike the tube, is not so quick in its action as it might be if the motion were produced by a spring. The hammer, as will be perceived in the figure, has a considerable space to pass through ere its face strike the tube at b. The motion has to be generated by the pull of a line, which changes its direction by passing round a small axis; and, having a very small leverage at the beginning of the motion, it requires a strong and continued pull to produce a smart blow and instantly draw the hammer back. This lock requires a much stronger jerk than the common spring flint-locks. The hammer has to beat down the head of the tube, and if the pull is not strong and continued the tube is not exploded. It

advancing, in continued change of distance and position, to that proximity which they must attain to attack batteries or fortresses with effect, and particularly in firing at steam-vessels, running at full speed across the line of fire of a battery, instead of stopping to engage it in its strongest direction. In this case coast battery guns will be required to "shoot flying" (Art. 383), but they will have little chance of hitting active steamers at considerable distances, unless, in aiming the gun, allowance be made for the distance the steamer moves in the time elapsed between the firing of the gun and the shot striking the object; in fact, unless the action of the lock and tube be so quick as to produce the most instantaneous possible discharge, the chances of hitting in such shooting will be very remote.

373. This important manner of igniting the charge was first attempted by fixing the lock to the ventfield out of the way of the explosion from the vent. For this purpose it was necessary to make the tube of a rectangular form, so that one part might receive the percussion of the cock, and the other part convey ignition to the charge. This construction was found, however, to be so sluggish as not to accomplish the great desideratum in naval gunnery, which is, that the firing of the charge and the actual delivery of the shot from the gun shall take place as quickly as possible after pulling the trigger-line, in order that there may be little time for any alteration to take place, from the motion of the ship, in the aim of the gun. Thus it was necessary to devise some means by which the hammer, after having struck fairly upon the head of the tube placed in the vent, should instantaneously slip or be drawn aside, so as to be out of the way of the explosion through the vent. Various modes of effecting this have been devised in the British and in other naval services, but the most efficient and simple implement of this nature is that which was invented by an American named Hidden, and patented in 1842. The hammer

a Ordnance Memoranda. Naval Percussion Locks, by Lieut. Dahlgsen, U. S. Navy, Assistant Inspector of Ordnance.