still worse disaster, that of carrying away the fishes into strange waters and destroying the ponds.

The fundamental rule in carp-culture is that the water be of the same depth in summer and winter. If the supply of water is too plentiful. great quantities of mud are carried into the pond, embedding the grass which grows in it and on its banks; this, in consequence, will rot and poison the water.. The carp immediately desert such water on account of its offensive odor, and retire from their proper feeding places to depths dedcient in the production of food.

The mud, which is being constantly reproduced, consists of decomposed plants. From these, different gaseous compounds develop themselves in midsummer, and the fishes become sickly in consequence. In this case, especially if they rise to the surface seeking for air, more water must be supplied through the inlet-sluice, when they will recover by degrees. A casualty of this description may occur in very large ponds, though no overflow may have taken place.

Pernicious gases develop themselves from the mud even in winter, but they rarely have any bad effects, being injurious only if the water is covered by ice, when the fishes may die of suffocation. For this reason, large apertures should be cut into the ice for the supply of fresh air in ponds thus affected.

PLAN FOR ARTIFICIAL CARP PONDS. See pages 205 and 206.

I, breeding pond for spawning fishes and spawn; 11, pond for small fry; III, pond for large fish; a, supply of water; b, inlet; c, collector; o, outlet.

In Fig. 13, is presented a plan of ideal carp-ponds, purely artificial, which conform to some American methods of fish culture.

The foregoing is Doctor Hessel's plan for the general construction of carp pounds. To carry the plan into execution, a level or slightly slo

ping situation is required. By this method all danger from freshets can be avoided, providing the location itself is never over-flowed, or even if the pond embankments are above high water and are kept well sodded, so as to prevent washing away by slight currents. Locations liable to overflow should be avoided, if possible.

Peirce's American Method.

The matter comprising the foregoing pages is mainly compiled from foreign sources-Austrian, Italian, German, and French-the larger portion being from the German. Since 1873 I have collected every available translation upon the subject. In some cases I find much of the matter to be repetitions of previous writers, and frequently it is impossible to determine with whom it originated.* I have had considerable correspondence with German fish culturists upon the subject. Although the mass of matter from which the foregoing compilation has been condensed would equal from four to five hundred of these pages, yet I believe that all which is of practical value is herewith collated. For the purpose of perfect connection and harmony, I have found it necessary to introduce considerable original matter into the foregoing pages.

From their first introduction into this country I have given the food carp every possible attention; have had charge of the Government distributions in eastern Pennsylvania and southern New Jersey; have been carefully breeding them myself and have planned and superintended the construction of a large number of carp ponds for prominent parties in Pennsylvania, New Jersey, and Delaware. Based upon the most careful and patient observation and experience stated, I have devised certain methods of culture which I think are in advance of any hitherto practiced. Some of my devices are patentable, and I have been repeatedly advised to patent them. I shall not do so, but in the following pages cheerfully hand them over to the public for whatever they may be worth. I will here refer to my long experience as a general fish culturist for the purpose of saying that I do not consider such experience of much practical value to the carp culturist for the reason that the food carp is almost wholly unlike any other variety of fish in this country, excepting in its breeding habits, which, of course, are similar to all members of the family Cyprinidæ perhaps the most extensive of any in American inland waters, and embracing a large variety of common brook and pond fishes such as the roach, dace, and chub. The Chinese golden carp, of which the aquarium gold fish is a specimen, is also of the same family, and its breeding

[* This reminds me that I have, during the past three years, written a large number of articles upon this subject for many of the leading journals of this country. I very often find these articles in other journals mangled almost beyond recognition, the sense in a great measure destroyed, sometimes completely reversed. In two or three instances, editors of prominent journals have solicited these articles from me and then deliberately taken such liberties as above described. I mention this matter here to say that I am unwilling to father all which appears in public journals over my unattested signature.—PEIRCE.]

habits quite similar. I mention these facts here to show that the requisites in carp culture are unlike any other variety of food fish culture. In this connection I can, however, refer with more satisfaction to my hydraulic engineering experience of over thirty years, trusting that the results as applied to the construction of carp ponds, and illustrated in the following pages, may be of practical advantage to those engaging in this interesting and important industry.

System Indispensable.

No person should for one moment think of engaging in carp culture, except with the same degree of system which is required to render any other industry a success. Nothing must be done in a haphazard manner, nothing left to chance. Most of those commencing the business, or desiring to, seem to think that if they have a permanent supply of water, no matter in what shape, whether a lake, mill-pond, ice-pond, brick-yard hole, open stream, ditch, or even a permanent mud-hole, they have only to introduce a few carp, when, after a brief time, they expect to gather a perpetual harvest. Most of those who have already engaged in the business will find their locations briefly described in the foregoing enumeration. Their efforts will prove unsatisfactory in most cases. Such of the waters named as will support fish are almost certain to contain different varieties of the family Cyprinidæ, with which the food carp is sure to hybridize, and such offspring is utterly worthless. Quite a number of parties in different States have during the past fifty years or more been engaged in raising the common gold-fish in ice-ponds, or other ponds very simply prepared for the purpose. As the business is of little account, many persons having these ponds have introduced therein the food carp, (the government supplying them free.) The result is that some of these parties are selling the progeny thus bred at enormous prices, while at the same time they are of no value whatever. Some one has sent me a circular issued by one of these parties, with a nicely engraved specimen of what he terms a German carp. It is unmistakably a hybrid of the food carp and common gold-fish. It will be charitable to suppose that the publisher of that circular is ignorant in regard to the absolute worthlessness of the fish which he is offering for sale at various prices, up to five dollars each. Concerning these haphazard methods of culture, one conclusion is inevitable. Within a few years, there will be a "hue and cry" in widely extended localities that the carp is a fraud, and carp culture a humbug. On the other hand, those who commence and conduct the business according to the most-approved methods, maintaining the same degree of system required for any successful business, will find the industry very interesting, simple, requiring little attention, and, withal, exceedingly profitable.

The illustrations upon the following pages are from plans which have been carried out under my personal supervision, and are, therefore, practical instead of ideal. In devising these plans and methods, I have kept

constantly in view the fact that the food carp is naturally a vegetable feeder, though also feeding readily upon microscopic and larger animalculæ, which breed or live upon various aquatic plants. Some parties who assume to give information concerning carp culture write knowingly as to the feeding of carp, the kinds of food required, &c. It is true that hungry carp will eat any vegetable matter that a hungry pig would consume, while the latter would nearly or quite starve if it only had access to the natural food of the carp. I boldly maintain that in order to succeed in carp culture, these fish should not be fed at all, except when nearly ready for the table, and then in the manner which I will describe further on. Their ponds should be inexhaustible pastures, where they 'can feed at will. If artificially fed, they will cease foraging, and hang FIG. 14.

around the artificial feeding places. Carp cannot be raised by any system of artificial feeding for much, if any, less than fifty cents a pound. It is probable that they will sell at about twenty cents a pound.

Granting now that my premises are correct, it must be evident that carp ponds should be constructed with especial reference to an ample supply of natural food within constant reach of the fish. To accomplish this, it is necessary that the water should be kept at the highest degree of temperature possible from atmospheric contact. Shallow ponds and sunny locations then are important factors. And another equally important requisite is that the surplus water discharges from the bottom instead of the surface of the ponds, thus constantly drawing off the

SECTIONAL VIEW OF PEIRCE'S CARP POND-SLUICE. See pages 210 and 212. coldest water.

Warm water is absolutely necessary in order to produce a luxuriant growth of aquatic vegetation, as well as myriads of animalculæ. I have succeeded in accomplishing, as it seems to me, all that can be desired in this direction by my method of contours for pond bottoms, as shown by Figs. 14 and 16, and particularly by means of the pond-sluice, shown at Figs. 15 and 16. Simple as is this device, it is the result of

FIG. 16.

(CROSS-SECTION OF CARP POND THROUGH COLLECTOR, SLUICE, AND EMBANKMENT. See pages 210 and 213.

many years' experience in the construction of fish-ponds. If anything more simple, cheap, or effective can be devised, I shall be pleased to recommend and introduce it.

Directions for Construction.

These sluices are made of common inch lumber or of thicker material zup to two-inch plank. I use inch lumber in most cases. Fig. 15, which