Military works are not exactly the kind of literature we look for from the United States. The gigantic European wars which ensanguined the early years of the century, make us apt to depreciate all contests that have since occurred. With Austerlitz and Jena, Leipzig and Toulouse, Salamanca and Waterloo, fresh in our memory, we scarcely heed the gallant actions of which Hungary and Northern Italy have recently been the scene. Still less do we regard, otherwise than with a smile, the easy triumphs obtained by Anglo-Americans over Indians and Mexicans. And, therefore, we were glad to find, on examining these two bulky volumes of _Military Reconnoissances_, that they had other claims to interest besides the narration of unequal combats between the stalwart and intrepid children of the Union and the degenerate descendants of the Spanish Conquistadores. Their military portions are quite subordinate, and they may be read as books of travel, written by highly intelligent and scientific men. They comprise the notes and reports of several American staff and engineer officers sent at different times to explore New Mexico, Texas, the country of the Navajos Indians, and other wild and little known districts south and west of the States--to which much of the territory thus travelled over has since been annexed. The most copious and interesting of the reports is that of Major (then Lieutenant) Emory, who, in June 1846, received orders to repair to Fort Leavenworth, with three junior officers, and to report himself and party to Colonel Kearney, as field and topographical engineers to his command. Colonel Kearney's column, rather magniloquently styled "The Army of the West," was destined to strike a blow at the northern provinces of Mexico, particularly at New Mexico and California. This "Army of the West" was on a very diminutive scale, consisting of two batteries of six-pounders, three squadrons of dragoons, a regiment of Missouri cavalry, and two companies of infantry. It was part of Lieutenant Emory's instructions that, when military duties permitted, he and his subalterns should give their time and attention to the observation of the regions they were to traverse. The calls upon their military services proving extremely limited, they diligently pursued their peaceable and scientific researches, to which we are now indebted for a closely printed volume of notes, a large number of drawings of scenery, plants, antiquities, Indians, &c., and a map, as large as a table-cloth, of the route of the expedition. The other and more lately printed volume, more miscellaneous, and perhaps less generally interesting in its printed contents, surpasses its companion in the merits of its pictorial portion, consisting of seventy-five plates, many of them very curious, and some of them remarkably good specimens of the new art of printing in colours.