Claim. "What I claim as my invention, is, 1st, the combination of the fan, oblong box or spout, and cylinder, for the purpose and in the manner described; and 2d, the combination of the two aprons, operating for the purposes and in the manner described; and also, these in combination with the combined fan, spout, and cylinder, as described."

DESIGNS FOR APRIL, 1849.

1. For a Design for Carpets; Peter Lawson, Lowell, Middlesex county, Massachusetts, April 3.

Claim. "Having thus fully described my design for carpets and other similar fabrics, I desire to secure the same by letters patent, a full illustration being given in the drawing accompanying."

2. For a Design for Carpets; Peter Lawson, Lowell, Middlesex county, Massachusetts, April 3.

Claim "Having thus fully described my design, and illustrated the same by the accompanying drawing, I claim and desire to secure the same by letters patent."

3. For a Design for Carpets; Peter Lawson, Lowell, Middlesex county, Massachusetts, April 3.

Claim. "What I desire to secure by letters patent is the above described design, for weaving into carpets and other similar fabrics, as fully set forth in the accompanying drawing."

4. For a Design for Furniture Ornaments; Cornelius & Co., assignees of Isaac F. Baker, Philadelphia, Pennsylvania, April 10.

Claim. "What we claim as our invention, is the above described design called Major Heyward, as fully set forth in the drawing hereto annexed, and the use thereof as a furniture ornament, in whatever manner the same may be applied."

5. For a Design for Furniture Ornaments; Cornelius & Co., assignees of Isaac F. Baker, Philadelphia, Pennsylvania, April 10.

Claim.What we claim as our invention, is the above described design called Cora Munro, as fully set forth in the drawing hereto annexed, and thereof for ornamenting furniture, in whatever manner or in whatever combination the same may be applied for that purpose."

6. For a Design for Stoves; George E. Waring, Stamford, Connecticut, April 10.

Claim. "What I claim as my invention, is the new and useful design for cooking stoves, which I call the Republic, as appears from the foregoing specification and the drawings attached thereto."

7. For a Design for Stoves; Chas. J. Woolson, Cleveland, Ohio, April 10. Claim. "What I claim as new, is the configuration and arrangement of said ornaments as designated and represented."

8. For a Design for Stoves; John and Alexander Morrison, assignees of Abram Haney, Troy, New York, April 17.

Claim. "What I claim as my invention, is the combination and arrangement of ornamental figures and forms, represented in the annexed accompanying drawings, making an ornamental design for a coal stove."

9. For a Design for Stoves; Samuel H. Ransom, Albany, New York, April 24.

Claim. "What I claim as my invention, is the combination and arrangement of ornamental forms and figures, represented in the accompanying drawings, forming an ornamental design for a cooking stove."

MECHANICS, PHYSICS, AND CHEMISTRY.

For the Journal of the Franklin Institute.

On the Dimensions of Steam Engine Chimnies. By MR. H. F. FAIRBAIRN.

The inquiry which appears in the June number of the Journal of the Franklin Institute, on the subject of the dimensions of steam engine chimnies, is one of the greater importance to Philadelphia, as it is certain that both beauty and profit can be made to arise out of the chimnies of the manufacturing establishments which may be founded in the city in future times. Philadelphia may be much beautified by the graceful forms of its steam engine chimnies, and a great annual saving in the consumption of fuel may be also made, in a city where fuel is destined to be at all times. dear. Pleasure and profit may, therefore, be found in the construction of chimnies upon true mathematical rule.

Speaking comprehensively, the same rules may be given for the building of chimnies as for the proportions of columns; that one-half of the diameter should be diminished between the base and the capital; that the length of the shaft should be eight times the diameter of the base; and that the chimney should be circular in every part.

The same laws of resistance govern material and invisible substances; the cannon ball, the smoke from the cannon, and the sound of the cannon, all travel in the same direction, and with a velocity proportioned to the resistance of the air or the land. And as the sound of the cannon, so the sound of the human voice, and the sight of the human eye, must be governed by the same force of resistance to its progress over surfaces; and as the most gradual diminution of the diameter from the perpendicular line produces the least singularity, and therefore the least resistance to the passage of the eye over the external surfaces of a column, so the same form and dimensions will allow of the least resistance to the passage of smoke

over the internal surfaces of chimnies, and that chimney is the best which will the most rapidly transmit the smoke to the external air.

The finest steam engine chimney which yet has been erected in England is that of the West Middlesex Water Works Company, at Turnham Green, in the vicinity of London. This chimney is more beautiful as a column than the monument of London,-a pillar which was built by Sir Christopher Wren, in commemoration of the great fire in the reign of Charles II. It is crowned by a Corinthian cap of fine proportions with every other part of this noble specimen of a steam engine chimney, which is only deficient in the inferior color of the bricks of which it is built, and in its position, which is neither on elevated ground, nor in a part of the country where its beauties can be very fully displayed; but the proportions of this chimney are considered to be complete.

In the town of Manchester, in England, there are also many steam engine chimnies of great beauty of proportion, by means of which immense quantities of bituminous coals are burnt without any loss of heating power, these chimnies seldom exhibiting the appearance of sensible smoke. The cotton manufacturers of Manchester vie with one another in the height and proportions of the steam engine chimnies, and some failures, in the foolish extreme of building the highest and most ambitious, but, at the same time, too perpendicular chimnies, have brought those now erected to be generally perfectly columnar in form, and not more ornamental to the town than economical in the consumption of coals, and very greatly beneficial to the health of Manchester, by the cessation of the black cloud of smoke which formerly vulgarized that great English manufacturing town. However large the outlay of money for the chimney, this is now seldom considered by the manufacturer, for the saving of coals, and the efficiency of the steam engine, repay almost any expense so incurred; and it has been long since discovered that Manchester may be improved by the beauty of the steam engine chimnies, and that the pocket of the manufacturer may be improved at the same time.

Two specimens of design in this description of architecture, taken from a work on Manchester, which was published some years since, will be found on the following page.

In these chimnies the internal diameter is uniform throughout the entire length of the shaft, and this is all that can usually be expected to be obtained without an increased expense, which will seldom be undergone by manufacturers for the purpose of carrying out the mechanical and the chemical principles which apply to any particular trade. But on true scientific principles, the internal diameter should certainly be diminished gradually as the chimney ascends, for it is clear that, as the smoke and gas pass further through the brick work, which has been cooled down in the proportion in which it is removed further from the furnace wall, (the original source of the heat,) the surface of resistance ought to be decreased and the chimney made narrower. As the heat of the sinoke decreases its condensation increases, and its expansion and ascending power diminished in the ratio in which the heat is lost. A gradual compression of the internal diameter would be the perfect mode of constructing chimnies on all the chemical and mechanical rules which apply to the passage of heated air.

The chimnies here shown are externally of an octagonal form, this being thought, by the author of the work on Manchester, to be capable of a finer ornamental effect in the blending of light and shade. "The association of light and shade is more striking in the octagonal than in the circular form of chimnies. In the former, the three great degrees of light and shade! are produced, namely, light, middle tint, and shadow. In the latter, the

extremes of light and shade, pass insensibly into each other, and produce but a feeble effect when compared to the finer and the clearer tints of the octagonal form." There is much good taste in these observations, and the effect of light and shade is still more worthy of attention in the production of the ornamental of Philadelphia than of Manchester, as the climate is

not so clear in England, and the effect of light and shadow very much less marked and imposing than in the United States. The sky in Pennsylvania is of the dark blue color of the parallel latitudes on the Mediterranean Sea, and as the effect of the minarets and other columnar structures of Venice and Constantinople is derived from finely graduated proportions, when seen against the finest of skies, and as there is no smoke perceptible from the chimnies of the greatest elevation in the manufacturing districts of England, (for the combustion is rendered perfect by the powerful draft of these chimnies,) so in Philadelphia there will be, still more than in England, a removal of all traces of black smoke where anthracite coal is in use, and consequently a removal of that which mars the purity of the architectural effect of a column seen against the usually clear blue sky.

An octagonal chimney is, therefore, recommended for its production of strong tints of light and shade, and for its variety as amongst other chimnies of the circular or the square form, and because it is not more expensive of construction than a chimney circular throughout.

Respecting the ornamental work of a chimney, its shewing the cap of the Corinthian or of any other order of columnar architecture, it is requisite that keeping be studied with reference to the general architectural character of the city in which the building stands. The city of Philadelphia is plain-was laid out by a man eminently mathematical in his mind; utility was in the view of the founder of the city of right angles, but then utility includes proportion, and in proportion all solid beauty finally resides. The Corinthian column may be thought to be not in true keeping with the general character of the architecture of Philadelphia, nor are there wanting those who think that all ornaments to columns have been the production of ages when taste has been on the decline; that neither the acanthus flower nor the horn of the ram are in their natural places when growing out of the tops of columns of stone, but that the Doric columns of the Parthenon remain the most impressive, although the plainest, of all the structures of the columnar kind. The chimnies given from the work on Manchester are of a description suitable to the general architecture of Philadelphia, plain but not absolutely without ornament, with pedestals and tablets of marble or other material, recording the history of the erection of the place, and becoming a monumentum in perennio to the manufacturer and citizen of Philadelphia, who shall have built the finest architectural column and saved the most anthracite coal at the same time.

There is some difficulty to be expected in the establishment of a perfectly scientific system of chimney building in the city of Philadelphia, as there are erroneous models already in existence, the errors being very grevious of those which are the highest, and the best shown with regard to their dimensions, internal and external, and which are the most inquired after by those who are erecting iron works and other manufactories in the interior of the State.

The chimney of Messrs. Powers & Weightman, manufacturing chemists, in Spring Garden, Philadelphia, is the highest in the United States. This chimney is square and its internal diameter increases towards the top; two errors which have been disseminated from this chimney extensively through the State, almost all the iron works which have been erected during the last ten years having chimnies of similar form and internal dimensions as