The fish-hatching establishment at West Barnstable, Mass., was begun in the spring of 1868. The experiments have as yet been confined mostly to trout, of which we have hatched this year some 60,000, as well as 2,000 salmon ova which were procured in New Brunswick by the State Commissioners of Fisheries, by whom they were presented to us. As the process of hatching goes on during the transport of the eggs in wet moss, we lost several by their batching on the way in the cars. x, x, x, x, x, x, springs, a, a, a, drains, c, hatching house. D represents a series of ponds for young fish, E, E, E, spawning ways. 6, 6, plank troughs. The two ponds between E, K, E, are for spawning nsh. The large pond represented by dotted lines, on the right of this, is used as a reservoir for fish. The dotted lines on the cat above the ponds represent aproposed series of ponds. Atankis also placed at this point, indicated by the x on the left of this series of proposed ponds. The place selected lor building the ponds to contain the parent trout, was a swampy piece of land at the head of a brook of considerable size, running into the salt water after a course of a mile and a half or two miles, and containing a half dozen or more pure springs, the waters of which formed 'lie fountain head of the stream. Two ponds have thus far been made by excavation, each about forty feet long by twenty feet wide, and from three to four and a half feet deep. They are connected together, the same water being used for both ponds. The supply of water is about eighteen square inches, and is taken from tanks made of plank, varying in size from ten to fifteen feet in length, and from four to ten feet in breadth, sunk in the soft mud at the points where the springs come to the surface, and as deep as was necessary to reach the substratum of sand, which was generally about five feet. These tanks have no bottom planks, and the water wells up through the sand at the bottom, forming reservoirs of living water of even temperature, summer and winter, and not subject to freshet or variation in quantity. The temperature of the springs varies but little from 48 throughout the year. There are now about seven hundred parent trout in the two ponds, ranging from throe-quarters of a pound to three pounds in weight. It is calculated that the first pond will sustain over 2,000 fish of the larger size, while in the second three times that number of smaller fish will thrive. This is allowing one large fish or three of the smaller size to the cubic foot. They are fed daily with live minnows and shrimp caught on the adjacent salt marshes, or, when they cannot be conveniently obtained, with chopped liver, the roe of codfish, etc. The ponds are stoned, and one of them which was built in low, wet land, is cemented on each side of the stones. Having learned by former experience that trout will spawn in the pond, and the ova thus be lost if its bottom is sandy or gravelly, we covered the bottom, where its nature seemed to invite the fish to this operation, with flat Btones, thus obviating the difficulty so far as we have observed. Aquatic plants, mosses, etc., were introduced and now cover the bottom, not only providing a large amount of food in the form of Crustacea, snails, etc., but also supplying to the water the necessary chemical elements which are being constantly exhausted by the respiration of the fish. The water enters each pond through a plank trough, the sides of which are sunk nearly to the level of the ground. These troughs are fifty feet long and three and a half feet wide, and are filled to the depth of six inches with coarse gravel, over which there are six inches of water flowing with a slight current to the ponds. As it is the habit of the trout to seek shallow running streams to spawn, they eagerly resort to these spawning ways when ready, and are taken by closing the bottom of the way, and driving the fish into a bag net at its entrance into the pond. They are then removed in tubs to the hatching house, for the purpose of taking the ova from the female and impregnating them with the milt of the male fish. The modus operandi is as follows : The female fish is grasped with one hand by the back and shoulders, the vunt lieing hold under the surface of the water in a tin pan or other vessel partly filled, while with, the other hand the abdomen is gently rubbed or pressed toward the vent. If the ova are mature and ready to be shed, a slight pressure is sufficient to extrude them. The same operation is then gone through with the male; if his milt is mature, it will flow in a small quantity into the vessel. A few drops are sufficient to impregnate thousands of eggs. The milt and the ova are then gently stirred together, and allowed to remain undisturbed for five or ten minutes. The water is then poured off, new water is gently admitted to wash the eggs, and they are ready to be placed in the hatching troughs. It may be as well to state here that the spawning time for trout is from October till March, the principal spawning months being November and December. It is generally cal- culated that a trout weighing one pound will produce 1,000 eggs; the larger and smaller ones in the same general proportion. I have known, however, during the past season, a trout of less than half a pound in weight, to deliver 1,000 eggs by actual count. The first requisite now is a supply of pure spring water for hatching the eggs,—neither too warm nor too oold. Prom 45 to 50 is the best. Every degree warmer or colder will make from six to eight day's difference in the time of hatching. Prom 37 to 54 is considered the limit within which to hatch trout. By a calculation in Mr. Norris' book(" American Pish Culture "), it will take one hundred and sixty-five days with water at 37, and thirty-two days with water at 54. The hatching house in the establishment we have spoken of is a wooden building twenty feet long by twelve feet wide, into which water is admitted about three feet above the level of the floor, from springs immediately in the rear, inclosed in sunken tanks, as before described, and covered so as to be out of reach of cold or heat. To enable the water to be brought in at this hight from the floor, the house is sunk three feet in the ground, and the boards are covered with a heavy coat of pitch inside and out, to a point above the level of the sur- j rounding ground to prevent their rotting. The amount of water now used in the house is what will flow through two faucets, one jch in diameter, with a moderate pressure. This is led, in the first instance, into a straining trough (Pig. 2), running across the width of the building, where it passes through flannel strainers, d, to insure its purity. It then flows into a distributing trough (6), which is parallel to the i straining trough and a few inches lower, from which, by , means of faucets, it is let on to the hatching troughs in such quantity as may be best. The hatching troughs (Fig. 2, c) are placed at right angles to the others, and are sixteen feet long, fifteen inches wide, and eight inches deep, and are six in number with covers upon hinges, the top of them being about fifteen inches from the floor. They are lined with slate, one-half of an inch thick, upon the sides and bottom, with transverse subdivisions; every two feet made of the same material and two inches in hight. A fungus growth, very detrimental to the ova, is unavoidable when wood only is used. The bottom of the troughs is covered with about one inch of moderately fine gravel, and over it flows a constant stream of screened spring water about an inch deep, the lower end of the trough being depressed two inches. On this gravel the impregnated ova are placed in a single layer. In about three weeks the eyes can be seen in the impregnated eggs, appearing simply as two black specks; the blood-vessels of the future fish may also be seen, and from this time its development may be traced daily in the shell. With the temperature of the water at 48, we may look for the hatching of the ova from the forty-fifth to the fiftieth day. A trout just hatched is about three-eighths of an inch in length, and has attached to it an umbilical sac of several times its own bulk, which sustains the yonng fish for about forty days, when it is absorbed. The young fish may now be let out into the waters it is desired to stock. They will thrive if placed in a brook even at this early age, such waters supplying an abundance of minute particles of food. If reared in confinement, however, they must be fed with raw liver chopped to the consistency of blood and mixed with water, with the yolk of eggs grated very fine and treated in the same way, or thin sour curds. The latter food is perhaps the best as it sinks more slowly, and trout seize their food in transitu, paying little attention to it after it reaches the bottom. We have sought only to give such a general description of a fish breeding establishment, and of the habits and treatment of the fish, as would give some idea of the practical parts of the art of pisciculture. There are many details connected with the subject which we have not touched upon. They can be found very thoroughly treated of in any of the modern works on pisciculture, of which Norris' " American Pish Culture " is the latest and most practical. In the above all general considerations have been avoided. It would, perhaps, have been as well to have stated that the arguments in favor of artificial hatching of eggs are based on the small proportion of them that are hatched when deposited in a stream, by the fish following the course of nature, and the very large proportion when hatched by artificial arrangement. The many enemies of fish spawn (other fish, water insects, birds, rats, not to speak of sediment, freshets, ice, etc., etc.) reduce the number of the eggs sadly, it has been calculated by English pisciculturists that not one salmon reaches the proper size for the table out of every thousaud eggs deposited in the stream. As the salmon migrates to the sea when weighing only a few ounces, it would, however, be more subject to casualty than the trout.—American Naturalist. Improved Awnings Wanted-—A Suggestion, In the midst of the great advance of mechanic art, and the cultivation of all those means of comfort which go to make what we may well consider refined civilization, there is often a strange and unaccountable neglect of certain very palpable matters, the inconvenience of which, strangely enough, is constantly recurring to us, and yet brings no reform. Every city in our Union is, and has been subject for many years to the positive nuisance of what are called " awnings; " a stupid device to protect goods in store windows from the action of the sun—and this at the expense of the public comfort. To effect "which purpose the plan, almost without an exception, is to use sail-cloth, either stretched or on roller. In very heavy rain the awnings that through a negligence, far too common, are left spread out over the sidewalks get rilled with rain-water, and ever and anon, deluge the passengers who are necessitated to walk under them. They all are claimed to be water-proof; and such is the actual fact, for they do discharge the water as in the manner stated; and in proof of which so many witnesses can seriously testify. The wind frequently assists in this ejection of water; and does more, for it makes such serious rents in these sail-cloth ceilings that the rain, like the express trains, " goes right through, without stoppage!" And, even where the things are fairly rolled up (more through economy on the part of the proprietor than for any regard for the comfort of the dear people), the framing yet remains to catch the falling rain and transmit it in heavy drips to the recipient dresses and silk hats whose wearers have the luck to be on hand. A cry of " stand from under! " would be altogether vain, for there is a forest of such bare poles or bars still awaiting the unfortunate in his fancied escape. It is literally running the rain-let. Now, in sober sadness let us ask—why is this shameful nuisance permitted ? Have we no better means of shedding the sidewalks from the sun than by this antiquated makeshift? Our areas have been made pleasant with the light of day transmitted through ground-glass, There surely is no reason why ground glass, of a much less thickness, could not be used in sliding-frames for the purpose now so bar barously monopolized by sail-cloth. Whether it rained or not, the glass would prove a protector to the foot pas-_ senger. And moreover, the merchant might have his sign on the glass, and with the aid of artistic taste this side walk covering might be made a most desirable decoration as well as a necessity to our street architecture. We merely make the suggestion in the hope that some ingenious inventor may turn his mind to a subject that all have more or less a feeling appreciation of. Let some fitting substitute be given to the public, and municipal authorities peremtorily abolish the existing trespass ings on our streets in the form of those awnings; a sound so closely akin to the other expression—awful, as to be truly suggestive.—Sloan's Architectural Review. The Nichols Steel Patents. For the past few months we have heard much talk about the Nichols patent processes for the conversion of malleable iron and white cast-iron articles into steel; but, more from the want of time than curiosity or interest, we did not visit the works of the Canton Malleable Iron Company, where the experimenting has been done until recently. Five patents have been granted to Mr. Nichols and the members of the Malleable Iron Company jointly, and although they are for different processes, each does its work so thorough, ly that we could not decide upon a favorite. Two are for converting malleable iron castings into steel. One of these is an instantaneous process, and the other requires from one to twenty-four hours, depending upon the size of the articles, The one we esteem for its quickness of action and the other for its superior production. Another patent is for converting white cast iron into steel. The article was taken right from the foundery floor- and packed in annealing pots, and then placed in the ovens precisely after the manner of making malleable iron, differing only in the chemicals used in the pots. This patent we look upon as especially valuable. We were shown plow points thus made that were heated under our observation, hammered to a fine edge and thus tempered so hard that after breaking off a point to see the quality of the steel we readily scratched our name upon the window glass. We were also shown many other articles, among them knife guards used by reaper and mower manufacturers, and by them made of wrought iron at great expense. By far however the most interesting experiment we witnessed was under a patent for refining steel or restoring burnt steel. We saw a piece of steel broken, one half of which was thrown into the fire and burnt until the particles looked lifeless and granulated easily. This same piece was again heated and plunged into the chemical bath and in a moment came forth, not only restored to life, but in comparison to the piece held in our hand it was much finer, and upon test much superior in strength. Another patent secures a process by which caBt iron is hardened more thoroughly and permanently than by any other known means. The saving that will accrue from the use of this process in the manufacture of car-wheels alone must be enormous. We look upon these processes as wonderful and, in our opinion,will in a year's time develop themselves into immense value, and we feel proud that the patents are held by Canton citizens.—Canton (0.) Repository and Republican. THE English parliamentary committee upon the proposed channel tunnel between England and France, have had an interview with the Emperor of the French, and have obtained a copy of the report of the French special commission appointed to examine into the practicability of the proposed work. The report is favorable, and indorses the pi ans of the English engineers as feasible.
This article was originally published with the title "A Fish Farm" in Scientific American 21, 7, 101 (August 1869)