During the few years which have intervened since the discovery of fish culture, its practise has advanced with rapid strides, and although it is still little more than in its infancy; the laws which govern its management have been so far ascertained and applied that it is now an established art, capable of yielding vast results for the benefit of mankind. The days of doubt and uncertainty have passed away, and numerous experiments lending invariably to the same end have established it on a firm basis. For a time cautious persons, even when most enthusiastic could not help questioning in their own minds what the final outcome would be, and whether all that was predicted for the new undertaking would be realized, but success in all well considered and properly conducted attempts has swept away fear and hesitation, and experience may now be said to have fully confirmed the highest hopes of the most sanguine. The possibilities which fish culture suggested were so far beyond what can be obtained in other fields of human labor, so greatly exceeded the best results in agriculture that it seemed impossible that they could be realized, or that this enterprise would have remained so long undiscovered or undeveloped. But day after day and year after year the theory has been put in practical operation, where all its steps could be and were accurately noted, and the incredible increase and profit obtained left but one conclusion possible. No persons could be more cautious, more slow to express a positive opinion, or to accept a hasty judgment than the authors of this work, as they can show by ail their writings, acts and utterances, but they feel at last that they and the public can give perfect credence to the claims of fish culture, provided it be conducted as intelligently and wisely as other departments of modern human labor.

It must not, however, be forgotten that this new art is as exact and exacting as any other, nor that it has its limits and must be managed with care and not slurred over or slighted. To the ignorant and indifferent it will yield no more than the cultivation of the land and possibly not so much, and precisely what those limits are of which we speak and what are the requisites of circumstance and manipulation, this work is intended to show. This is meant for a practical book on a practical subject, in which nothing shall be stated on conjecture; no mere fancy picture however alluring shall be presented to the public, and the bare facts with plain directions shall be given that all who wish may read and understand, and all who have the opportunity may practice what is herein set forth. With that view no attempt will be made at grace of diction, and scientific names, formulas and information will be omitted as far as is thoroughly consonant with the purpose to be attained, and no farther. Many misapprehensions exist in the public mind in relation to a matter which has dawned upon the world so lately and so suddenly, expectations as extravagant in some directions as they are depressed in others, and while one man will try to raise the best of fish from the worst of waters, another doubts if anything can be achieved from the most favorable opportunities. It is the function of this book to correct these mistakes and prevent these blunders.

The culture of fish has been gradually extended from one species to another until we have a fair idea of what can be done in all cases, and those even who try new experiments have much to guide them, and can, up to a certain point tread with assured footsteps. At first the only species treated by the artificial method was the salmon, the most valuable and highly prized; thereafter the process was applied to trout, then to shad and afterward to whitefish, lake-trout, herring, perch, bass, striped bass, sturgeon and many others with more or less success. The greatest promise for purely artificial manipulation is with the salmon, the trout, the lake-trout and the shad, but the close study of the habits of other varieties which followed the attempts with them have so familiarized the fishculturists with the necesities of their growth and increase that a subsidiary branch of fish-culture has grown up in which the natural process is assisted, protected and developed. This incidental method has yielded benefits that,allowing for the difference of labor and money expended, approach those reached through the more scientific and intricate management of the higher classes of fish. All these processes will be considered, explained and fully detailed in order that the utmost benefit may be received by the reader from the knowedge acquired by more than twenty years of study and experiment in the production and growth of fish. We believe that we can safely say that the authors of this book have had a hundred fold more experience in pisciculture than any other persons in this country, and that by them, or under their control, the most important inventions and discoveries have been made, either in the best methods of impregnating and hatching the eggs, or in protecting, transporting and growing the fish. They have been practically engaged in fish culture since its introduction into America; have studied, labored, and experimented in all its departments: have tested all theories propounded abroad and at home, and have had under their charge in the New York state hatching house the largest and most efficient establishment in the world for producing actual results, and for separating fact from error. As a consequence they feel they can promise that nothing will be given as an established fact that has not been fully proved by the personal experience of the writers, for they are resolved to make this book trustworthy if it is nothing else.

Before entering upon the details of practical management, it may not be unadvisable to take a general review of fish culture, and give some suggestions of universal application. It has been said that an acre of water would produce as much as five acres of land, if it were tilled with equal intelligence. In making such a comparison, it must be borne in mind that the crop of one needs no manure, requires no care during its period of growth and after it has once been planted, and that it is harvested by simply taking it from the water in which it dwells. It is almost wholly profit. The other must not merely be planted but must be fertilized at great expense, and worked and cultivated with assiduous labor of man and beast, and finally when at last successfully harvested and saved from destruction through disease, insects and the elements, it yields but a meagre advance upon the cost of time and trouble. It has been the habit to cultivate the land and neglect the water, the one has been reduced to private ownership and constitutes a large part of individual wealth, while the other is a sort of common property too little appreciated to be reduced to possession where this is possible, and abandoned as a sort of waste to yield what it may without care to the tew chance persons who make a living out of it. If our wheat crop is damaged or the corn crop diminished or the cotton crop short, the public press rings with lamentation, and the country mourns over a national calamity. But the supply of our fish crop yielding millions of pounds of food per annum may be in process of utter annihilation, and yet no voice is raised, and we sit by with folded hands in idleness. The land we value dearly, because to till it costs us dear in sweat and thought, and the water we despise because it yields its free will offering without an effort on our part. We have tilled the ground four thousand years, we have just begun to till the water.