It is so distinctly evident that the immense advance which is at the present period in operation upon military weapons and practice must extend its influence to dress and appointments, that a treatise of this kind would not now be complete in its parts without a reference to them. Dress will be affected pre-eminently, in a manner which has not, as yet, attracted much, if any, public attention. It will be indescribably more than ever important to distinguish the troops of one nation from those of other nations, by uniforms that can be known afar off. Among the most perplexing, hindering, and revolting incidents of a campaign, are those of mistaking foes for friends and friends for foes. Facts are the best arguments; and a few of those which occurred under the author’s own observation, in a corps probably as little liable to make mistakes as any that ever stood on a battle-field, are offered in enforcement of this consideration. During the retreat from Madrid, in the grey of the morning, after having been harassed through the greater part of the day before by impudent dashes of the French light cavalry, a Spanish cavalry patrol was fired upon, under the very natural impression that they were Frenchmen, re-commencing their previous practice. After this, while engaged in the pursuit of a beaten enemy through a mountainous and intricate country, the battalion was compelled, as a matter of reasonable prudence, to scale a rocky hill, in order to take up a position of defence against three battalions in blue, which had just appeared as if moving to intercept the line of retreat. When a quarter of an hour had been wasted, they also turned out to be Spaniards. On a subsequent occasion, in following up a charge in line, from the thick smoke that still hung on the enemy’s infantry a body of horsemen, of which some evidently were cuirassiers, broke furiously upon the front. It had all the appearance of an effort of the French cavalry to cover the retreat, and the whole fire was for a moment concentrated upon it, until some of the headmost horsemen, falling almost upon the bayonets, were perceived to be English light dragoons. These are a few, and only a very few, of the evils which have already arisen from indistinctness in uniform. If, then, the mischief was so great in connexion with the limited and uncertain power of the old musquet, what will it not be with the distant and accurate fire of the long range rifle? A group of your own staff officers, a patrol of your own cavalry, or a battalion in blue of your own infantry, eight hundred yards off, might be almost destroyed before it could be possible to correct the mistake; while bodies of the enemy might, from your uncertainty, pass and repass with corresponding impunity. _Whatever uniforms, therefore, we adopt or maintain, it is evident that, for cavalry as well as infantry, broad_ NATIONAL DISTINCTIVENESS _should be a most predominant consideration_.