superiority of the American rails has undoubtedly contributed to this result. In spite of these encouraging signs, these sure indications of the success which at no distant day will reward this branch of American industry, it must not be imagined that checks and reverses are hereafter to be escaped. The production of the year 1857 promised in the summer to be much larger than that of 1856; but the panic of September wrought the same effect in the iron-business as in all the other manufactures of the country, and in the spring of 1858 more than half of the iron-works of the United States were standing idle. Mr. Lesley states that the returns received in answer to the circular issued by the Iron-Association, July 1, 1858, were, almost without exception, unfavorable, and that these replies are sufficient to prove a very serious diminution in the production of iron for the year 1858. When the manufacture of iron, in its various branches, has expanded to its true proportions, and has reached a magnitude and importance second only to the agricultural interest of the country, the iron-masters of that generation may read in this first publication of the Iron-Association the record of the struggles and trials of their more adventurous, but less fortunate predecessors. The construction of the directory which constitutes the first part of the "Guide" might be improved in several respects. An alphabetical arrangement of the furnaces, forges, and rolling-mills, in each State, would be much more convenient for reference than the obscure and uncertain system which has been followed. If a State can be divided, like Pennsylvania, into two or three sections, by strongly marked geological features, it would, perhaps, be well to subdivide the list of its iron-works into corresponding sections, and then to make the arrangement of each section alphabetical. But convenience of reference is the essential property of a directory; and to that convenience the natural desire to follow a geological or geographical arrangement should he sacrificed. Some important items of information, such as the means of transportation, and the distance of each furnace or forge from its market, are not given in all cases; the power by which the works are driven, whether steam or water, is not uniformly stated; and the pressure of the blast used, that very important condition of success in the management of a furnace, is stated in only a very few instances. A useful piece of information, seldom given in the descriptions of forges and rolling-mills, is the source from which the iron used in the works is obtained; and it is also desirable that the nature of the work done in each forge or mill should be invariably stated. It would he interesting to know the number of men employed in the iron-manufacture throughout the country, and it would not seem difficult for the Association to add this fact to the very valuable statistics which they have already collected.