The elements of the first drills with minute instructions might be comprised in a hand book of one half the compass of Steuben’s tract; and this elementary work placed in the hands of all descriptions of troops, infantry, artillery, and cavalry, should be the first rule of practice for them all in common. This introduced, the government could at leisure prepare instructions for a more comprehensive course of manœuvres, and particularly hand books upon the same simple principles of drills for artillery, riflemen, and cavalry, in their particular branches of duty. It being to be understood as a fundamental principle, that as the movements and action of all kinds of troops are regulated by the movements of infantry; or in other words, as infantry compose the main body, line, or column; the riflemen, artillery, and cavalry must be governed in their movements by the main body, to which they are appendages or auxiliaries; and it is therefore required that they should know themselves how to execute the infantry manœuvres, in order that they should not, like the French at Rosbach, be confounded by movements of which they are ignorant. The profound mathematician may look down from the elevation of abstract science upon the cold common place of syllabic combination and Arabic numerical notation; but he owes his first knowlege to the alphabet of language and arithmetic; here he must have begun, and here the military man of whatever grade must also begin. He must learn the alphabet of military knowlege at the drill, he must take his lessons and learn them; he must study and practice what he has learned there, in order to teach; and the officer must learn both to command others and to obey. There is no science which may not be attained by earnest application and practice. But no science or art can be acquired or understood without both; and the more carefully that study is pursued and the more frequently it is practised, the more efficient will it be in the individual and in the regular mass of individuals. But practice is above all requisite, careful, frequent, constant, obstinately pursued practice. _But this is not yet a system._ We have exhibited the elementary branch of military instruction first, merely because it is the point at which every military body must commence; because this is what is now most wanted, and because while it is carrying into practical use, the general system containing all the purposes and uses of an efficient military establishment may in the mean time be prepared and digested. Having treated so much on this subject, its importance will excuse the discussion of it more at large. To the perfection of a military establishment for the U. States two things are essential. The _first_ is, that it should be such as to be equally applicable in its operation to the militia and to the army of the U. States, whenever the former are called forth.