Substituting this value of P, in eq. (1,) we have, ph dx 1 = -log. To determine a in terms of U, logarithms, - ... (2.) 1, we find from the properties of 11 When al in equation (2,) the whole work in one stroke becomes, = K U or L K (l—c)=K { log. a l-b ;+P(h—c)—p(l—c) } ...... ... (4.) Where L represents the sum of the pressures opposing the motion of the piston, as in eq. (A,) 10. When the work is required in terms of the water evaporated, the P, in this expression must be eliminated, by the expression given in 14. Substituting the values of U, and U, in the expression given in 7, we find, If R be put for the sum of all the resistances upon each inch of the piston, viz., F+L, (1+f)+p, then the maximum velocity will take place when, P ̧=R= This is the expression for the position of the piston, when the maximum velocity takes place; it is more accurate than that given in 8, inasmuch as Pole's formula gives the relation of the volume and pressure of the steam more accurately than Marriotte's law. It may not be improper here to observe, that the expression given for this point in the paragraph just referred to, neglects the pressure of the vapor in the condenser. Example 52. Required the work performed upon 1 inch of the piston, in example 1. Here, 58)= P=28, l=9, h=3, c=0, K=1, then by for. (4,) a =(+.00268) 1 .01279, b.00268, and U= 01279 log. .01279 X 9.00268 +28x3=174. It will be observed that this result nearly coincides with that obtained in example 1. Lond. Mechanics' Mag. FRANKLIN INSTITUTE. Extracts from the Reports of the Judges appointed to examine the Articles offered at the Fourteenth Exhibition of American Manufactures; held October, 1844. (Continued from Page 169.) The Committee of Judges on Hardware were highly gratified in entering upon the duties of their appointment to notice the general improvement in the hardware exhibited this season, particularly in cast-iron and hollow ware. In their investigations they have examined every specimen enumerated in the catalogue furnished them by the Actuary. In consequence of the number of articles submitted to them, their remarks must necessarily be brief: the first article is— No. 1001, one case of samples gilt buttons, made by Wadham, Webster & Co., Wolcottville, Conn., deposited by makers. These are a beautiful article, elegantly finished, but in no respects superior to those exhibited at the last exhibition. In some of the specimens there is room for better taste and skill in the die work of the figures. No. 1003, three saw setts, made by J. Flegel, Philadelphia, deposited by Jarvis & Webster. The committee could not discover any particular merit in these articles. No. 1004, one card of files, assorted, made by Robert Murphy, Philadelphia, deposited by maker. These specimens embrace nearly all the varieties of the small and delicate files used by jewellers, and particularly dentists; in their general appearance and finish they closely resemble the celebrated "Stubbs" Lancashire files. We learn too that the manufacturer can furnish an article fully equal to the specimens, at prices varying from fifteen to twenty-five per cent. below the same description of English files: with perseverance and a determination to excel, by the maker, this description of English files must soon cease to be imported. For his success in producing an article so nearly like the small and fine Lancashire files, the committee think the maker entitled to the premium of a silver medal. No. 1005, a frame and gearing with suspended doors, made by W. J. Forsyth, Philadelphia, deposited by maker. In this contrivance the committee believe that there is nothing new. No. 1006, half dozen patent coffee mills, made by John Rittenhouse, Germantown, Pennsylvania, deposited by Joseph G. Hensey. These are well and beautifully made, and sustain the high reputation which the maker has acquired. For their general excellence and finish the committee think the maker is entitled to the award of a certificate of honorary mention. No. 1007, a card of rasps and files, made by George Machen, Phil adelphia, deposited by maker. These are a good article, fully equal to any ever exhibited; they are well cut, of good proportions and strength, and in the strength of the tangs are superior to the foreign article of the same description; the maker is entitled to a certificate of honorary mention. No. 1008, one silver mounted hunting sword, made by Jacob Faser, Philadelphia, deposited by maker. This is a well made article, got up in superior style, and highly creditable to the maker's skill and taste. No. 1009, four pieces britannia ware, made by Joseph Morrow, Philadelphia, deposited by maker. These are a well made article; the color of the metal is good, the surface free from "blows," and finely polished; the soldering of the spouts and handles remarkably neat, and in general finish will compare favorably with the same description of foreign goods. The forms of these articles might be improved without adding to the expense of the manufacture, by the makers exercising a little more taste. The committee think these specimens entitle the makers to the award of a certificate of honorary mention. No. 1010, one revolving rifle gun, made by John Herr, Freindsburg, Berks county, Penna., deposited by Christr. J. Fell; in this article the committee could not find much to admire either in taste, or workmanship. No. 1011, one coffee mill, made by A. Pritz, Hanover, Penna., deposited by A. Maslin; this appears to be a fair, serviceable article. No. 1012, three cast-iron planes, made by the Savage Manufacturing Company, Hanover county, Maryland, deposited by Yarnall & Walton. These are new articles, and appear to be well made for service; their merits, however, are not known to the profession. No. 1014, one stand of sample gravitating locks, made by S. C. Bemis, Springfield, Massachusetts, deposited by E. F. Moody. These appear to be a good article, well and tastefully made. No. 1015, one of Jenk's patent carbine, made by N. P. Ames, Chicopee Falls, deposited by E. S. Handy & Co. This article is well made in every respect in strength and proportions; it is faultless. Of its peculiar merits in loading at the breech, the committee are unable to give an opinion. No. 1017, one case of rules, made by Bremner & Co., New York, deposited by Foote & Thompson. These appear to be a well made and good article: creditable to the maker. No. 1018, one case of sample wrenches, made by Merrick, Springfield, Massachusetts, deposited by Foote & Thompson. These are good, fully equal to any others in the exhibition. No. 1020, one case of guns, rifle and musket, made by John Krider, Philadelphia, deposited by maker. All these articles are excellent specimens of the maker's skill; in strength, just proportions, good taste, and excellence of workmanship and finish, the committee think them the best articles of the kind ever exhibited, and fully entitle the maker to the award of a silver medal. No. 1021, four bundles of scythes, made by Mansfield & Holman, Smithfield, Rhode Island, deposited by Wm. P. Cresson & Co. These are all well made, and fully equal in all respects to any exhibited at former exhibitions. The domestic manufacture of this article, has, for several years, entirely excluded the importation of the foreign article. No. 1022, one case of rules, made by Herman Chapin, New Hartford, Conn., deposited by William P. Cresson & Co. These are a good, creditable article. No. 1023, two card handles, made by F. Stanly, N. Britain, Conn., deposited by W. P. Cresson & Co. No. 1024, eight planes, made by E. W. Carpenter, Lancaster, Pa., deposited by Yarnall & McClure; these are a well made, and appear to be a good, serviceable article. No. 1026, one card and four packs of pins, made by Slocum, Jillson & Co., Waterbury, Conn., deposited by F. V. Krug & Co.; this being comparatively a new article of American make, claimed much of the time and close attention of the committee. In the production of this article the manufacturer has been eminently successful; the specimens exhibited are well made in every respect, the heads smooth, the shanks well proportioned, smooth, and elastic, and the whole article beautifully finished. The committee think the maker entitled to the award of a silver medal. No. 1027, three scythes, made by Hale, Waters & Co., Millbury, Massachusetts, deposited by Smith & Lewis; these are good, and equal, in all respects, to any other specimens exhibited. No. 1028, two cards of door locks, latches, and door springs, made by T. L. Littlefield, Philadelphia, deposited by maker; these are all well made, and beautifully finished articles, in design and execution highly creditable to the maker; they appear to be well contrived for use, and worthy the attention of the trade. The maker is entitled to the award of a certificate of honorary mention. No. 1029, one frame hay and manure forks, made by John F. Hopkins, West Cambridge, Massachusetts, deposited by David O. Prouty. These are elegant specimens of the maker's skill, the forks being beautifully finished, and highly elastic; the maker is entitled to the award of a certificate of honorary mention. No. 1031, forty sheets of sand paper, made by Betts, Lafferty & Co., Philadelphia, deposited by maker. This is a good article of the usual quality to be found in the trade. No. 1032, one case of butchers' knives, &c., made by Henry Huber, Jr., of Philadelphia, deposited by maker; we are glad to notice the improvement presented in these specimens; they are an article of very general demand, and have constituted quite an item in our importations. The specimens are of good proportions and strength, and withal well finished; the maker is entitled to the award of a certificate of honorary mention. No. 1035, one case samples of awl blades, made by Thorp & Hall, Philadelphia, deposited by makers; these are a new article of American manufacture, being the first, we believe, exhibited; a little more experience, we doubt not, will enable the makers to produce an article VOL. IX, 3RD SERIES. No. 3.-MARCH, 1845. 14 in all respects equal to any imported. For the general excellence of these specimens, the committee think that the Institute will be warranted in awarding a certificate of honorary mention. No. 1037, one bench vice, made by C. C. Chapman, Philadelphia, deposited by maker; this appears to be a well finished article: it is adapted to holding parallel and wedge form figures; for the design and workmanship, the maker is entitled to a certificate of honorary mention. No. 1038, one box of cotton and wool cards, made by Prentiss & Brother, Philadelphia, deposited by maker; these are a good article, and fully sustain the makers' reputation. No. 1039, lot of sad irons and hollow ware, made by Savery & Co., Philadelphia, deposited by makers; it is highly gratifying to observe the very great improvements which have been made in the manufacture of these articles. The sad irons are remarkably smooth in the casting, the handles well made, of good form, and the face and sides of the iron finely finished. The hollow ware is decidedly the best ever exhibited; the form is good, remarkably smooth, and of great evenness;-for these excellencies the committee think the makers entitled to the award of a silver medal. No. 1040, a case of lever suspender buckles, made by James Bingham, Philadelphia, deposited by maker; these articles are silver, and should more properly come under the notice of the committee on silver ware; in the judgment of the committee, however, they are a neat, well made article, and highly creditable to the maker's taste. No. 1042, eight signal lanterns, made by Wm. Porter, Trenton, N. Jersey, deposited by Charles Jewell; these are a fair article. No. 1043, one fifty blade knife, made by W. Richardson, Philadelphia, deposited by C. C. Watson; the committee doubt whether this is American make, at all events, it is a useless article, and of inferior workmanship. No. 1044, a case of britannia ware, made by Hall, Boardman & Co., Philadelphia, deposited by makers; these articles will bear examination; the color of the metal is a good imitation of the English "britannia metal," the surface is good, and finely finished, the soldering neat; in all respects they are highly creditable to the makers, and fully equal to any exhibited. The forms of many of these articles might be more graceful, without additional expense to the maker; the makers are fully entitled to the award of a certificate of honorary mention. No. 1048, one pair of steel skates, made by Frowert, Philadelphia; these are disreputable to the maker and depositor, Frank Shoemaker. No. 1061, one case of tailors' shears and hair scissors made by R. Heinisch, Newark, New Jersey, deposited by J. H. Harkness, Philadelphia; these articles are, in all respects, worthy the high reputation of the maker. In no branch of American cutlery has greater perfection been attained than in this; the committee have met with nothing equal to it from the most celebrated foreign workshops. In weight, strength, proportions, adaptedness, and beauty of finish, nothing more |