adapted to the containing of the air thus condensed, and to the supplying of the same in measured quantities, so as to operate upon a piston for driving and propelling machinery, as high steam is now made to operate. The means of doing this does not require any description, being perfectly familiar to competent engineers. The air is to be condensed into one large stationary reservoir, and by means of a connecting-tube and stop cock, transferred therefrom into other reservoirs connected with the vehicle to be propelled. What I claim as my improvement in the art of propelling cars, boats, or other vehicles for transportations, is the employment of the waste power of water, wind, or other natural or artificial sources of power, to the condensation of air, in the manner, and for the purposes, hereinbefore set forth.

Remarks by Dr. Jones.-It has been repeatedly proposed to drive railroadcars, &c., by means of condensed air, instead of by steam, and to erect stationary engines for the purpose of filling the requisite reservoirs, and we believe that the thing was attempted in England. Were there not serious practical objections to the plan, it would certainly pre. sent many advantages, but these are so weighty, that they are not likely to be removed. Among them is the perpetually diminishing power of the condensed air, as every stroke of a piston must lessen its elastic force; to graduate the quantity emitted from the reservoir, in proportion to this diminished force, would be very difficult; and, besides this, there ought, when the reservoir is renewed, to be a pressure of several atmo spheres above what is required in a steamboiler, or it will soon be so far exhausted as to be inadequate to the production of the intended effect, as they would have to be exchanged whilst under a pressure of two or three atmospheres.

The present patentee does not propose to remove the foregoing, or any other objection to the use of condensed air, excepting it be the necessity of erecting stationary engines to effect the condensation; and to accomplish this, he depends upon the employment of means which would generally be more difficult, precarious, and expensive; in many places, the means of condensation proposed to be used would not be found within many

miles of the stations where the reservoirs would be wanted, and there are, in fact, but few situations where the means of applying waste power would not be a costly undertaking.

NOTES AND NOTICES.

Our

The Poor Boy.-We delight to trace the progress of genius, 'alent, and industry, in humble life. We dwell with pleasing emotion on the cha raeter and conduct of individuals who, from a "low estate" of obscurity and poverty, have raised themselves, by their own native energy, to affluence and stations of respectability and renown. country is full of examples of this description. They fall under our observation every day. Gideon Lee was once a poor boy, and in the occupation of a farmer. He is now in affluent circumstances; recently Mayor of New York, and at present a member of Congress. Charles Wells, late Mayor of Boston, was a journeyman-mason. Samuel T. Armstrong, the acting Governor of Massachusetts, and at the head of several philanthropic institu tions, was once a journeyman-printer. There are those living who recollect George Tibbets a daylabourer, and know him now as a gentleman of wealth, influence, and enterprise-the Mayor of the city of Troy. Stephen Warren, the well-kuon and esteemed President of the Troy Bank, rich in this world's gools, and rich, too, in public spirit and deeds of benevolence, came from an obscure town in Connecticut, penny less-a shoemaker. Perseverance, energy, and industry, and moral worth, produced this consummation of human wishes. New York Messenger.

Railroad to India.-Long before ten years more, I trust to see a regular communication, in 45 days, between England and India, in every month of the year, established on a permanent and well organised footing. That the communication can be accomplished in 45 days is beyond a doubt, even allowing nine days for the several necessary stoppages. Mr. Waghorn, in a letter dated Alexandria, April 7, published in the Morning Chronicle of May 11.

Communications received from Mr. HodsonS. S. (next week)-Mr. Hennell-Mr. Dickson-A Projector-A Subscriber-Mr. Briggs.

The Supplement to Vol. XXIV., containing Titie, Contents, Index, &c., and embellished with a Portrait of Mr. Walter Hancock, C. E., is now published, price 6d. Also the Volume complete in boards, rice 98. 6d.

British and Foreign Patents taken out with economy and despatch; Specifications, Disclaimers, and Amendments, prepared or revised; Caveats entered; and generally every Branch of Patent Business promptly transacted.

LONDON: Published by J. CUNNINGHAM, at the Mechanics Magazine Office, No. 6, Peterborough-court, between 135 and 136, Fleet-street. Agent for the American Edition. Mr. O. Rich, 12, Red Lion-square. Sold by G. W. M. REYNOLDS, Proprietor of the French, English, and American Library, 55, Rue Neuve, Saint Augustin, Paris.

CUNNINGHAM and SALMON, Printers,
Fleet-street.

IMPROVED MODE OF TRACTION THROUGH

CANAL TUNNELS.

The tunnel on the summit level of the Huddersfield Canal is 34 miles in length. The method at present for passing boats through is by men laying on their backs on the boats, and acting against the top and sides of the tunnel with their feet to propel the vessels forward. In July, 1834, a premium of 100 guineas was of fered for the best plan for facilitating the passage of the boats through the tunnel, provided it was adopted; in consequence of which, the following plan was projected:

Fig. 1 is a longitudinal section of the engine, boiler, &c. Fig. 2 is a ground plan of boilers, pipes, boat, &c. Fig. 3 is another plan, giving a top view of engine, boilers, taup, chain, trough, &c. AA, the engines, of 5 horses' power each; BB, the boilers, with their tubes, chimneys, &c.; C C, the pipe for conveying the smoke, &c. from under the boilers to the force-pumps; DD, the forcepumps for drawing the smoke, &c. from under the boilers, and discharging it into the canal J through the pipes E E. The smoke is discharged in an opposite direction to that in which the boat K is moving, thus assisting to propel it forward. It will be perceived in fig. 2 that the smoke is forced out at either end of the boat, according to the direction she is moving, by opening and shutting the stop-valves at the junction between the two pumps. By this aforementioned arrangement I do away with the nuisance of the smoke, cause the air to pass freely through the fire to support combustion, and likewise assist to propel the vessel forward. It is necessary to state, that the steam is to be got up previous to entering the tunnel; then the damper of the chimney is shut, and the pumps become substitutes for the chimney. Fis the taup-wheel, which works in the chain for drawing the boats through the tunnel. G is the trough in the centre of boat, which conveys the chain L to and from the taup-wheel. This trough is raised in the centre to allow the water to run back into the canal that is brought up with the chain; as also for the ascending and descending of the chain to and from the taup-wheel. The trough forms round the taup-wheel, except where it is in contact with the chain, to prevent any water running into the boat. The bottom

which is driven round by the taup-wheel to prevent the chain from rising off it in case of jerks, &c. In fig. 3 the chain is seen going over the taup-wheel, and extending from one end of the tunnel to the other, made fast at each end, and laying at the bottom of canal; ascending on to the taup-wheel, and falling again into the canal, as the boat moves along. The chain is of simple construction, easily manufactured and soon repaired in case of accident; it weighs 361bs. to the yard. Fig. 4.

Fig. 4 is a side-view of the valves which are to be opened and shut alternately, as the boat is reversed in her direction through the tunnel, to admit of the smoke being forced out in the opposite direction to that in which the boat is moving. The speed of the taup-wheel determines the speed of the boat, consequently any speed can be attained that is practicable in a close tunnel.

Your obedient servant,

EMANUEL WHARTON.

Manchester, April 26, 1836.

P.S.—It will be proper to inform you' that I never had the opportunity of explaining the plan to the Canal Company, nor any one else that sent plans. The engineer, to whom the competing plans were submitted, advised the Company not to adopt any of them, but to use stationary engines.-E. W.

DUST PROTECTORS.

Sir,-We have in this country contrivances to keep us from the wet and from the cold, why not from the dust? When some men go from home, it suits them to have but one coat, and it does not suit them to have it made shabby; and if he does not put on an upper coat, must be the case, which does not exactly do this hot weather. Under those circumstances, had he a thin brown Holland garb to put on, would it not be serviceable? Would not a thin light covering

for clothes and hats find a ready sale in the London ready-made cloth shops.

AN OCCASIONAL TRAVELLER ON
THE Солсн Тор.

HISTORY OF THE FOUNDATION OF THE BRITISH MUSEUM.

Sir,-As you have occasionally devoted some of your pages to the subject of our national Museum, with a view to its improvement and the extension of its public utility, I venture to transmit to you some particulars respecting its foundation, not generally known, and which are not to be found in the article British Museum," lately published in the Penny Cyclopedia, and which common report attributes to the pen of Sir Henry Ellis. The following sketch has been compiled with great care, principally from contemporary writers whose authenticity may be relied on.

Sir Hans Sloane, the founder of the British Museum, one of the most eminent physicians and naturalists of the eighteenth century, of whom an interesting memoir may be found in the Biographia Britannica, was not only distinguished as a man of science, but also as a liberal and patriotic citizen. He was a governor of most of the metropolitan hospitals, to which he was not only a constant benefactor, but also left considerable sums to them at his death. He set on foot the scheme of a dispensary for the poor, and gave to the Apothecaries' Company a piece of ground at Chelsea for a botanic garden, who," that their successors and posterity might never forget their common benefactor," caused a marble statue by the celebrated Rysbrach to be erected to his memory. Sir Hans Sloane was also instrumental in establishing the Foundling Hospital, and formed the plan for bringing up the children, which proved the best that could be devised. He was the first who introduced into England the general use of bark, which he applied successfully to the cure of many diseases. Sir Hans Sloane also gave a sanction to the practice of inoculation by inoculating two of the princesses, which more effectually established this great discovery than all the treatises that had been written on the subject. But the share he had in the foundation of the British Museum will most effectually preserve his name from oblivion. Having with great labour and expense, during the course of his