My own experience on this subject has been limited to its application for the saving of life from shipwreck, where the application of a line to the rocket limits its range and velocity; but sufficient is left in a rocket of an inch and a half diameter effectually to carry out a line of a quarter of an inch diameter to a distance of 600 or 800 yards: that is, more than double the distance obtained by either Manby’s apparatus or the rockets now in use; which, lamentable to state, are quite inadequate to the purposes for which they are intended. Though the improvements in rifled cannon are at present only in their infancy, they have nevertheless attained to an extraordinary degree of perfection, verifying all our predictions to the letter. A writer in the _Times_ makes the following statements in favour of Mr. Whitworth’s improvements:-- “While some men of really inventive talent, and a great many charlatans, have been permitted to waste the public money in trying vainly to improve our artillery, it seems passing strange that it should not long ago have been discovered how impossible it was to hope for successful results in the direction in which they were working. It was clear that while increased range and precision of firing were wanted, it was nearly as important to bring the charges of ammunition and the weight of metal in guns into more manageable proportions to each other, and to the facilities for transit on active service. No sensible man can have witnessed the frightful damage done to the efficiency of our army in the Crimea by the exigencies of the siege-train during the winter of 1854-5 without being impressed with this conviction. The principle of the rifle offered an obvious suggestion for the proper means of working out the foregoing problem; but then for artillery, rifling by grooves would not do without the use of a pliant metal in the projectile, and the cost of lead rendered its application to that purpose impracticable. It was necessary, therefore, to alter the existing mode of rifling, and to modify the bore of the cannon, so that an iron projectile could be discharged from it, rotating on its own axis in the line of flight. This result once secured, it is obvious that a field-piece or gun of position would become a rifle on a large scale, and that the same immense increase of range and of penetration which had been realised by the smaller weapon as compared with Brown Bess, would be placed at the command of the artillery service. It is consolatory, after a series of failures worthy even of Brunel in launching the _Leviathan_, that the country has at last the well-grounded hope of an improvement by which our ordnance may be placed on a proper footing. In pursuing those careful experiments which he undertook for the Government, principally to improve the rifle, Mr. Whitworth, the eminent machinist, adopted a polygonal spiral bore of a uniform pitch, but more rapid than could be attained by grooves.