invention of Mr. Brougton, improved by Mr. P. Burgess. The grinder is a horizontal circular plate of cast-iron, 10 feet in diameter and 2 inches thick. The upper surface is planed and has ribs beneath to give it strength. This large plate is keyed on the end of a vertical shaft, which is made to revolve at a velocity of forty-five revolutions a minute. The plate of glass to be ground is placed upon the circular table just described; half-way between the center and the circumference an adjustable frame of the proper weight is placed upon it so as to confine the edges and prevent the plate from slipping away. This frame carries in its center a round rod, standing vertically, which is kept in its place by two bars fastened to the frame of the machine. This arrangement prevents the frame from moving away, but does not prevent it from revolving. There is room on the circular table for four glass plates, disposed in a similar manner, at a distance from the center. A trough full of sand, with an aperture in the bottom proportional to the quantity of sand required, is suspended above. The machine is put in operation by making the ten feet table revolve. The frames above being held in their place, the glass they carry is rubbed by the table, and the velocity being greater at the circumference of the table than near the center, these frames themselves begin to revolve in a contrary direction. This motion, which is a result of the first, has the advantage of regulating the friction by successively bringing every point of the glass near the center, where the friction is least, and near the circumference where it is greatest. The polishing machine is nearly similar to the grinding machine. The only difference is that its upper surface is formed of wooden rings covered with felt, which are screwed upon the cast-iron table, and that these circular rings are eccentric to the table, and leave between them parallel circular ridges of nearly the same breadth as the wooden rings. The glass plates are placed upon this machine as upon the other, in exactly the same manner; but instead of sand falling on it from a box, oxide of iron or rouge, thoroughly mixed with water, is used, and is applied to the felt with a brush. A writer in the Tribune, says, he saw a plate of glass taken from the grinding machine and placed on the polishing table, which came out of the machine perfectly smooth on one side after one hour. It takes ten hours to obtain a similar result by hand labor. The grinding machine is calculated to produce equal results. And, when we call to mind that the St. Gobain Company, which seems to have the monopoly of the trade with the United States, makes enormous profits, and that the duty on glass plate is thirty per cent, we doubt not that the new company has in hand one of the best inventions of the time. WROUGHT IRON-FORGE HAMMERS AND FORGING. The Liverpool Albion, in noticing the January number of Orr's Circle of the Industrial Arts, gives some extracts from a paper on Wrought Iron in large Masses." We subjoin a few paragraphs from this paper : “The manufacture of wrought iron in large masses cannot boast of a very early origin. Although we read in the most ancient of Books that Tubal Cain, before the Flood, was an instructor of every artificer in brass and iron, it would doubtless have puzzled even that great founder of the iron trade, had he been furnished with an order to make the large masses of wrought iron required for a Great Britain, Persia, Marlborough, or Great Eastern steamship; and he would have been equally at a loss with many modern craftsmen, had he been requested to forge a monster gun,' or a doub.e-throw crank-shaft for engines of 1,000 horsepower. Were he again permitted to visit the world, the mighty machinery at work on every hand would compel the admission, that his trade had made great strides during his absence. These advances in the manufacture of wrought iron in large masses have taken place almost entirely within the present century, if not, indeed, within the last thirty years. Up to that period, the improvement apon Tubal Cain's (we presume original) inventions were of so limited a nature that, in the year 1820, the manufacture of a shaft-say of six inches diameter, and weighing fifteen or twenty cwt.-required the concentrated exertions of a large establishment, and was considered a vast triumph if successfully accomplished; whereas, we are now accustomed to forgings of twenty or thirty tons' weight, as matters of every-day occurrence, scarcely exciting the slightest notice. Nor do we stop even here--much larger masses will, no doubt, ere long, be manufactured for the construction of iron ships, which, in future years, owing to the increased size and strength of the plates, will be built upon a scale that would but recently have been deemed fabulous. This consideration, combined with the requirements of rapid communication, which demand more colossal engines, call for renewed energy in conducting this important manufacture. It may, perhaps, not be out of place to mention here, as a fact having few parallels in other branches of the industrial arts, that, almost without exception, all the improvements that have latterly crowded upon each other in this trade have originated with the hammermen or workmen themselves, and have been worked without even the protection of an exclusive patent right." After a description of ancient and modern forge hammers, the writer describes the materials consumed in the forge, the chief of which are the coals and the iron : "It is of considerable importance (he says) that care should be used in the selection of the fuel for the manufacture of forgings, as great difference exists in this important mineral, some being very much more suitable for the manufacture than others. The best for the purpose is a strong, dense, durable coal, possessing a good body, and having a dull, dirty appearance. Coal with a bright, clean look, easily broken, as a general rule, is not suitable. Of course, it is desirable that the coal should be as free from sulphur as possible, and that it should not contain any large proportion of those foreign matters which, having an affinity for iron, fuse on the bars in the shape of clinkers." In the manufacture of large forgings, Mr. Clay strongly advocates the use of puddled iron over scrap iron, for various reasons, one of which is, that— "Scrap iron is composed of many various qualities of iron, and all of them have their own special welding points. When worked together, one portion that is less refined is too much heated, and consequently deteriorated, before the more highly refined portions are at a welding heat; and we are thus placed in the awkward dilemma of either burning the one, or of being unable to weld the other. It may be said that this objection is a mere theoretical one, and that, practically, no such difficulty exists. This, however, is not the case, for the dif ference of temperature at which puddled iron and a highly refined iron weld is very considerable; although, from the difficulty of finding a really good pyrometer for these extreme heats, we are unable to give exact data in degrees. If any proof were required of this, which is a matter of every-day economy, it is only necessary to inquire into the heating of iron for our rolling-mills. It is a well-established fact, that, in the mixing of different descriptions of iron in the piles for that purpose, the hardest and most refined iron is always placed outside, and the puddled, or common iron, inside. Were a contrary practice pursued, and puddled iron of ordinary quality placed at the outside, and the highly refined, or scrap, placed in the center of the pile, the outer, or puddled, iron would be wasted and destroyed before the inner portion was sufficiently hot to weld.” GOLD IN THE FORM OF MALLEABLE SPONGE. The Chemical Gazette of London, in referring to this form of gold "which has been imported," it says. "of late years from America for the use of the dentists, and sold at prices between 7 and £8 per ounce," states that gold of a similar spongy character was obtained by the following method:- Gold free from copper is dissolved in "nitro-hydrochloric acid," keeping an excess of gold in the solution towards the close of the operation, so as to get rid of all nitric acid and avoid subsequent evaporation; any chloride of silver present is filtered off. The solution of gold is now placed in a flat-bottomed vessel and heated, and a strong solution of oxalic acid added; in a few hours the whole gold is deposited, and the supernatent liquid may be decanted off, taking care all the time not to disturb the gold at the bottom, and the vessel is then several times filled up with boiling water and decanted until the last washings contain no more oxalic acid. The gold is now carefully slipped on to a piece of filtering paper, and, by means of a spatula, gently pressed into the form of the desired cake, but somewhat thicker; it is then removed to a porcelain crucible and heated for a short time, somewhat below a red-heat, when it shrinks in dimensions, becomes coherent, and is similar to the American product in properties. As the American gold is of a reddish hue-it is propably precipitated by proto-sulphate of iron, and not by oxalic acid. NEW USES FOR THE CASTOR OIL OF COMMERCE. The cultivation of the palma-christa plant, which produces the seeds from which castor oil is pressed, has been somewhat extensive in this country, particularly in Illinois; but, owing to the limited use of castor oil, the demand has not been large enough to warrant extensive planting. But its application to other purposes may increase the demand and make its cultivation profitable--as it would be at $1 a bushel for the seeds in many places south of latitude 40°, up to which point the plant matures without much danger of frost, and although it grows much larger further south, it does not afford as great a yield in Mississippi as it does near the northern limit of its growth. New uses for castor oil have been discovered in France. M. Berris, a French chemist, declares that it is applicable to a great many industrial purposes to which it has not heretofore been considered applicable. He says: 46 By distilling castor oil upon concentrated potash, the sebacic acid and caprylic alcohol are extracted as separate products, which may be turned to a good account. The sebacic acid, having a high melting point, may be employed, instead of stearic acid, in the manufacture of candles, and if it be mixed with stearic acid, the hardness and quality of the candles are greatly improved, and in appearance they resemble porcelain. It is possible to use caprylic alcohol in all the purposes to which ordinary alcohol is put, particularly in illumination, and in the composition of varnishes, and from it certain other compounds may be derived, of remarkable odor, similar to those which are at present largely used in commerce." The French people expect that this discovery will prove of great advantage to the farmers in Algeria, since they can produce from a given quantity of land three times as much castor oil as they can olive oil, and twice as much as of palm oil, both of which productions afford good compensation to the cultivator. Shall we not make it equally profitable in this country? STATISTICS OF AGRICULTURE, &c. PUBLIC LANDS OF THE UNITED STATES. The annual report, for the year 1857, of the Secretary of the Interior, Hon. J. THOMPSON, Opens with an exhibit of the operations of the General Land-office, preceded by an historical sketch of the methods by which the public domain was originally acquired. In the following tables and remarks we have arranged the principal statistics and facts in the report :— 1,450,000,000 The surface of the domain, exclusive of water, is., . acres 401,604,988 Of which there have never been offered, and are now liable to public sale.... 57,442,870 And on Sept'r 30, 1857, there were subject to entry, at private sale, upwards of.. 80,000,000 Railroad grants of March, 1857, estimated. Of the public domain, there have boen disposed of by private claims, During the fiscal year ended June 30, 1857, and the quarter ended Of which there were disposed of— For cash (viz., $4.225,908 18).. Located with military warrants.. Returned under swamp land grant.. 5,300,550.31 7,381,010.00 3,362,475.96 5,116,000.00 22,889,461.00 363,862,464 1,086,137,536 21,160,037.27 Of the lands sold and located during this period, it is estimated that threefourths were taken for actual settlement. The amount of money received on cash sales is $4,225,908 18. This shows a falling off in land receipts from those for the corresponding period of the preceding year of $5,323,145 99, with a falling off during the same period in the location of lands with warrants of more than 20 per cent. This diminution is attributable to the withdrawal of the extensive bodies of public lands, along the lines of the railroads, in the States and territory to which grants of land were made during the last Congress, and also to the sale of large quantities of land at the reduced prices fixed by the graduation act of the 4th August, 1854, and to the fact that the demand for new lands has been, in part, satisfied by the States having lands for disposal under the swamp, internal improvement, and other grants. The report favors a change in the pre-emption law. As the pre-emptor is not required to make proof of, and payment for, his claim until the day appointed by proclamation for the public sale of the lands, an interest is created in opposition to a public sale by proclamation. It is also suggested that settlers upon unoffered lands should be required to make their proof and payment within a specified period. Pre-emptions upon unsurveyed lands are now limited to particular States and territories. The Secretary recommends a general law authorizing pre-emptions upon lands of this character, superceding and repealing special statutes on the subject; and observes, further, that in order to remove all doubt in the construction of existing law, pre-emption privileges should also be extended to alternate reserved railroad sections, in cases where settlements have been made after the final allotment. The enhanced value of such lands presents only a stronger reason why preference should be given to settlers over all others. There are 83 organized land districts, each having a register and receiver, for the sale and disposal of the public lands. There is none for either New Mexico or Utah. In New Mexico the public surveys have been executed to a very limited extent, owing to Indian hostilities. In Utah the surveys were rapidly advanced, until the Surveyor-General abandoned his post, owing to reported hostilities of the Mormon authorities at Salt Lake City. The extent of the surveys in the latter territory, since the beginning of operations, exhibits a sphere of field work embracing 2,000,000 acres. A due regard for the public interests, as well as for the prosperity of New Mexico, would justify Congress in establishing a land-office and a board of commissioners for the ajudication of Spanish and Mexican claims in that territory. It is important to separate private property from the public lands before the settlements become dense, and consequent conflicts of claim and title arise. NURSERIES IN THE UNITED STATES. With the increase of horticultural knowledge and the means for furnishing gardens and orchards with the choicest varieties of fruit and shrubbery, there does not seem to have been a corresponding increase in those products, which, if not the most substantial of the fruits of culture, are certainly the most agreeable and the most conducive to sociality and enjoyment. This state of things ought not to exist. There ought to be more attention given to the culture of fruit than has ever yet been given to it. It is one of the most agreeable things in the world to watch the development of one's own fruit, the growth of one's trees, to eat the luscious products of one's own industry. Whoever has an opportunity to plant a tree, and to line his fences with fruit-bearing shrubbery, and does not improve it, is guilty of a neglect not only to himself, and family, and friends, but also to the public in whose midst he resides. We recently observed in a number of Goward's Real Estate Reporter, published in Boston, a long list of the names of nurserymen in the Eastern, Northern, Middle, and Western States, which was prepared for that paper, and was an extension of a similar list previously published in Life Illustrated. Without referring to any of the prominent nurseries included in that enumeration, we now give a recapitulation of the whole number in each State, as presented in the list above mentioned: In this connection we present the following extract from a letter from Rochester, in regard to the nurseries of that city. In the list to which we have above referred, we find the names of the firms of nineteen extensive nurseries in the city of Rochester : "Few people at a distance are aware of the vast extent of the nursery business of Rochester. I cannot tell how many thousand acres are occupied in this way. Large fortunes have been made in the business, and still it goes on increasing. Messrs. Ellwanger & Barry are said to have one of the largest nurseries in the world, covering four or five hundred acres, while those of A. Frost & Co., though of comparatively recent origin, extend over two hundred acres, and employ one hundred hands. I might mention a dozen or twenty similar establishments. The neighborhood of Rochester has been fitted for growing fruit trees, and large as |