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while by awaiting the results of those made by foreign powers we can get our information at no expense to ourselves; that it will be time to start on the manufacture of ordnance when the need for it arises ; that the resources of this country are so great that a navy can spring into being at a moment's warping. We all know how very visionary such reliances are, how wide of the truth such expectations would be in reality. We have no plant where a steel gun of any considerable size could be made inside of many months, and, never having made one, we have no steel makers of experience in that particular branch. This very 9 inch B. L. R., spoken of above, has been under construction for nearly two years, and when finished will be but a make-shift. Now is the time when we should be learning, as well by failures as by successes, should be training skilled labor and should be increasing our facilities of manufacture.
Nor may the time be very far distant when we shall find ourselves engaged in a foreign war. As long as the Munroe doctrine is cherished so universally and so dearly by the American heart, just so long are we liable to be engaged in a foreign war at any time. The present question of an inter-oceanic canal may at any moment involve us in controversies with foreign powers. The minute it becomes for their interest to oppose or molest us for reason of this canal, in the way of free trade or otherwise, we are likely to find out that our inability to back up our Monroe doctrine is only too well known to them. They know how far we could enforce our dictations as to European intervention in the affairs of nations of the western continent. In the advent of such a war at what a disadvantage we should be ? Our forts with their present armament would leave our maritime cities at the mercy of a powerful enemy; torpedo defence, however admirable the system, however wisely planned or gallantly executed, can avail little except in combination with powerful ordnance. On the sea the same humiliating spectacle would be presented : a few cruising vessels, the fastest and luckiest of which might survive for a time and carry on a maritime guerilla warfare, would soon have no home ports open to them for protection or repair. Many desperate and gallant things would doubtless be done by the personnel of the Navy--and this we are warranted in predicting by reference to the past history of the navy—but can a great nation afford to wage war by a series of forlorn hopes ? Is it policy? Will it pay?
THE CHAIRMAN. I should like to ask the lecturer what, in his opinion, is the best gun for the navy.
Lieut. LYON. In the gun of the future we are as sure to come to a breech loader as we were to come to the same thing in small arms. As to the material of which it will be made, I should say that it would be of steel, as that metal is the strongest and most elastic one suitable for making guns that we know of. There is an element of uncertainty in steel forgings of large size that must of course be eliminated if possible, and for this reason, as well as for the practical knowledge to be gained by our steel workers and ordnance officers, we should now be making experiments. Taking the Krupp as the best type of large steel guns, we still know that quite a number of them have burst in service. In case of war, we can make very excellent guns on the Palliser system, casting the casings of such dimensions and length as we like, and not being limited, as now, by the form of old smooth bore guns.
There are still advocates of cast iron simply for rified guns, and their claim is that in the few experimental guns of that kind experimented with in this country, where the cast iron is exceptionally good, such violent powder and such vicious systems of rifling and projectiles were used as not to give the guns an honest trial. There were occasional pressures withstood of one hundred thousands, one hundred and fifty thousands, and even two hundred thousands of pounds, which would seem suficient to burst any gun. I think that, in case of an emergency, cast iron rified guns, even with enlarged chambers, could be used with our system of projectiles, and good powder, and derelop a very good life. The tensile strength of the iron in the casing of the 12.25 inch gun now at Sandy Hook is over thirty three thousand pounds per sq. inch, and that can well be guaranteed for future guns, with a good chance of getting it higher, besides which we know in this metal how much to trust, while with large steel guns so far mide, the probabilities are that there are parts where the metal of the gun is not up to that in the test specimens.
THE CHAIRMAN. It was my experience during the war, and doubtless other officers present had the same experience, that the distrust of cast iron rifles became very great, and I should feel very sorry to see that form of metal introduced again without much experiment.
Commodore RANSOY. What is the relative strength of cast iron and cast steel gun nietal?
Lieut. Lyon. We may take the strength of good gun iron as thirty-three thousand pounds per sq. inch. I do not know of any steel used for guns that is over one hundred thousand pounds per square inch tensile strength. A vastly greater strength for steel can be obtained, but it becomes too brittle for guns. In the jacket for the tube of a steel gun now ordered from the South Boston Iron Co., the tensile strength is expected to come up to about that figure, -one hundred thousand pounds.
Commanner SICARD. While it is true that steel specimens sometimes show a tensile strength of over two hundred thousand pounds per square inch, it must be remembered that such steel is very “high” and “short” consequently unfit for use in the construction of cannon, owing to its want of extensibility ;-especially would it be unsuitable for those parts contiguous to the bore. The effect of vibratory strain is disastrous to short metals, and it is found much better, in practice, to reduce the elastic and tensile limits of the steel, and increase its extensibility; as the molecules of the metal are then in such a condition with regard to each other that they may be somewhat separated or rearranged under strain without cracks being initiated. Personally, I am of opinion that in introducing steel guns we should not, at first, strive for very high tensile limits, but be content with low and soft steels, in which the margin of safety is large. This remark has reference to the body of the gun, as the outer jacket may be made “higher" without objection. For guns of moderate caliber, from sixty to eighty thonsand pounds seems a good figure to start on with an extensibility (at failure) of about 20 per cent. The extensibility of soft steel measured after fracture is much greater than that shown at the
failure” of the metal, which latter point is arrived at when the specimen under test no longer supports the maximum weight, but stretches as the weights are removed from the steelyards of the testing machine. After passing this point the "lite" of the metal may be said to be gone.
Lieut. Lyon. The steel ingots which I am about to cast at the Norway Iron Works for short tubes for 60 B. L. R.s, are to have, when forged, a tensile strength of eighty thousand pounds, an elastic limit of about thirty five thousand pounds, and an elongation at failure of about 17 per cent.
Commander SICARD. It will be safest at first (as I before remarked) to make our steel guns rather mild. In the introduction of the new armament we do not wish to have any accidents, and in fairly low steel there is safety. After manufacturers become accustomed to the production of gun steel we may proceed to harden the metal as endurance may require, though if it should happen that the bores of the soft guns wear too fast, they can be tubed.
I quite agree with Lieut. Lyon that in some respects the Parrott gun was far in advance of its time, notably in length of bore and in the twist of the rifling. The expansion system, also, though crude, was a step in the right direction.
Lieut. STRONG. What is the relative strength of the 8 inch converted rifle and Krupp guns of about the same caliber?
Lieut. LYON. I do not know the relative strength, but it can be calculated, always supposing that the steel is homogeneous and up to the qualities of the test specimens; but, as I said before, we have from experience always an element of doubt in large masses of steel as to its homogeneity. The doubt in the Palliser tube would be as to a defective weld, which would affect the longitudinal strength only of the tube. This latter gun would not, in case of rupture, burst explosively.
Commander SICARD. A comparison of the strength of the systems could be made if we knew the mechanical qualities of the metal in each case, and the amount of squeeze with which the Krupp rings are placed, but after all there would be a wide margin of uncertainty, owing to unavoidable errors in manufacture, the varying qualities of large masses of metal, and the uncertainty as to the exact amount of squeeze that has really been obtained by the placing of the rings. It is a well known fact that cracks have developed in many steel tubes, and have often resulted in the failure of the piece, while in other cases experimental guns have supported a very large number of rounds, long after the walls of the bore hare become covered with cracks and fissures, the exterior of the piece badly swollen, and the rings separated by the elongation of the piece. There is a want of uniformity in the qualities of current production from the steel works that will for the present necessitate the use of comparatively soft ingots.
Commodore RANSOM. Can we arrive at the exact tensile strength required?
Commander SICARD. It is not possible in the present state of manufacture to arrive exactly at the limits required, the efforts of the gun steel makers being still tentative. The furnace is usually under the direction of an experienced practical man, with whom should be associated a scientific metallurgist who is experienced in chemical analysis, etc. These men working together on sufficiently large orders to stimulate their ambition would doubtless make continual improvement in the product of their works.
THE CHAIRYAN. I am sure all present will agree with me in returning thanks to Lieut. Lyon for his interesting and able paper.
NEW YORK BRANCH.
FEB. 19th, 1880.
COM'DR E. O. MATTHEWS U. S. N., in the chair.
THE TRAINING OF SEAMEN.
By LT.-COMDR. F. E. CHADWICK, U.S. N.
MR. CHAIRMAN AND GENTLEMEN :
I can only hope to give a slight résumé of the methods pursued abroad in training men for the navy. But I shall, at least be able to show how much more attention has been given to the subject in nationalities which we have usually looked upon as far behind us in educational subjects and methods, than amongst ourselves. While we have admittedly, by almost all, been foremost in the education of our officers, both as to the time of the establishment of a system of higher education, and as to the extent of the education itself, we have been more than backward in doing anything for the enlisted men of the service; any real efforts in this latter direction being made long after the establishment of complete systems by the greater naval powers of Europe.
While England, France, Italy and Germany were all making radical changes in their training and treatment of men, we, for many years of the time these changes have been progressing, were almost perfectly supine and careless, depending for our supply of those who were to uphold the honor of the flag, upon the waifs of every nation which drifted to our shores. Nor did we only wait for them to come; we took them on board in every foreign port, until the crew of an American man-of-war represented almost every tongue and color.
The apprentice system, in existence between 1865 and 1870, gave us many excellent men, some of whom still remain with us, and who are amongst the best we now have. This system was however handicapped by the inducements held out to parents to send their sous on board ship with the prospect of having them enter the Naval Academy; a certain number of entries from the training ship being allowed yearly. The consequence naturally was that a large number of the