for casting I had made about thirteen years since, and the cock itself has been in actual use ever since 1825, during which time it has only required grinding about three times a very decisive proof of its utility. It is, I believe, altogether new, and has been made solely from my own directions.

Description of the Figures.

Fig. 1 is a longitudinal section of the cock.

A continued rotary motion is communicated by a bevil-wheel from the flywheel-shaft to the plug E, by means of the bar C, which works through the stuffing-boxes BB, and is firmly fixed into the plug E. The dotted circle D is intended to show the steam-pipe from the boiler, and the arrow the direction which the steam takes through the plug E and the pipe F, to the underside of the piston; G is the pipe leading from the upper side of the piston, from which the steam passes in the direction of the other arrow through E to the pipe leading to the condenser, denoted by the dotted circle H; 1 is a lever, with a handle against a cap or curved recess in which, the bar C works; and K a regulating screw; the use of which is to prevent the steam on one side of the plug and the vacuum on the other side from pressing it so tight into the hollow cone, as to wrest off the bar E, as also to allow of blowing through the engine previous to starting, by forcing the plug from its seat a little distance endways.

Fig. 2 is a cross section of the cock, C being where the bar passes through the plug at the line 2 in figure 1. It shows, likewise, how the steam passage is enlarged, by cutting out the solid brass round the bar C. The thin line commencing near to L is intended to show how much of the boiler side of the opening of the plug is cut away, it being in this allowed to act on the piston during threefourths of its descent.

Fig. 3 is another cross section of the plug, showing it as cut through at 3 in fig. 1. The dotted line H shows the portion of the passage leading to the condenser.

Fig. 4 is another section of the plug through the line 4 in fig. 1.

The modus operandi will be easily understood, if we suppose the plug to move in the direction of the arrows in figs 2, 3, and 4. When the crank is on its centre,

either up or down, the solid parts of the plug N and O will cover the passages G and F; as it moves forward, the part cut, out at D allows the steam to enter the passage G until the solid part L closes the passage, after which the steam in the cylinder acts by expansion until the solid part N closes the passage F, which will be only for an instant, as the crank is passing the centre; the condensing passage of the plug being cut away as far as practicable, so that both the passages are entirely closed whilst on the centre.

I conceive, that if this sort of cock were adapted by the high-pressure enginemakers, it would be of great service, as it would allow the steam to be cut off at any point by cutting away the plug on the steam side one-third, one-half, three quarters, or any other proportion, according to the wish of the engineer, and thus allow of its expansion to its full extent. Besides, it will not be liable to get out of order, particularly if the adjusting screw K is properly attended to.

Malisbury.

I am, Sir, Your obedient servant, W. BUCKLAND.

ON WATER AS A PRIME MOVER.

Sir, Mr. Galt has led the way, and has been followed by some of your correspondents, in what appears to me to be a most extraordinary delusion, viz. in considering a proposal to obtain power through the medium of Bramah's pressemploying water as a substitute for steam. Now, I humbly submit, that instead of the case being Water v. Steam, it is, in fact, neither more nor less than Steam v. Animal Power.

Kappa" has occupied several columns in one of your recent Numbers* with an elaborate account of the roundabout ingenuity which is often found to be exercised in fallacious pursuits. The total inapplicability of manual labour to locomotive purposes (through the intervention of machinery) has long since been clearly demonstrated, and almost every possible scheme for applying it has been resorted to in vain. The well-known and unalterable fact, that what is gained in power is always lost in time-might have shown Kappa" the inefficiency of his proposed scheme for propelling carriers' waggons;

* Page 514, vol. xxiii.

but, had he chosen to verify the truth of this law, and to have ascertained its application to his own particular case, he might have done so by a much easier and shorter road than the one he took. Instead of his 9-inch crank-De la Hire's double-acting pump, doubled-steam cylinder, &c. &c., all that would have been necessary was to have fixed a spur-wheel on the axle of the propelling wheels, and driven them by a pinion duly proportioned to the inverse quantities of time and power. The men's labour applied to the pinion by means of a winch-handle, would have produced all the effect to be derived from such a source, and more than could possibly be obtained by any more complicated train of mechanism.

An increase of power with an equivalent loss of time must have been the in evitable result, and the machine would have dragged its dull length along, at less than a funeral pace, much slower, indeed, than the common slow stagewaggons.

In good truth, the carrier's horses would have laughed their jealous rivals to scorn, giving them the go-by, and leaving them far behind to labour at their new and exalted vocation.

66

True, men do not eat either wood, coals, or coke; but it is not clearly shown, that two or three men" would have been so proud of their new occupation as to have toiled night and day for nothing

and kept themselves! " Kappa" states, that when two men were working the lever, the engineer dryly remarked," the principle throughout is good and correct, no doubt; it only wants a steam-engine to work the pump!" A keener piece of satire upon the whole affair could hardly have been uttered.

The principal error throughout this business consists in mistaking the prime mover, which is really the MEN; the water is only one of the means used for applying their labour in a particular form to the object required.

Hydraulicus" (p. 460, vol. xxiii.) is not free from this error, but he takes a more correct view of the result; the fact is, as he supposed (before he was misled by Mr. Galt's proposition), that no mo

tive-power could possibly result from employing Bramah's hydrostatic-press; for the production of intense pressure, this machine stands unrivalled, and this quality constitutes its unfitness to be a conveyer or transmitter of motion; under all circumstances equilibrium must take place.

So far as the employment of De la Hire's pump for the purpose of raising water, or as a fire-engine, is concerned, I would beg to refer "Kappa" to p. 114, of your 20th volume, where he will find a convenient adaptation of it to these purposes by

Your obedient servant,
W. BADDELEY.

London, Sept. 29, 1835.

AUTOBIOGRAPHICAL PASSAGES IN THE LIFE OF MR. NASH.

Sir, It has been to me, and no doubt to many others, no small matter of surprise, that the death of one who has for nearly half a century occupied so prominent a part in the history of metropolitan improvement as Mr. Naslı, should have been passed over with no farther notice than a meagre paragraph in the Athenæum, which was copied into your 617th Number. Since that time I have daily expected to see the announcement of the publication of some memoir, of one who has altogether changed the face of a great part of the fashionable end of our metropolis. Al though Mr. Nash's works are not built for posterity (and posterity will, no doubt, thank him for having so much consideration in sparing them the trouble of demolition), they are certainly the chef d'œuvres of what is capable of being effected with lath and plaster; indeed, so great a space of ground could not have been gone over in so short a time as has elapsed since the General Peace had it been otherwise.

Under these circumstances, I thought that it would be acceptable to the readers of the Mechanics' Magazine to transcribe some passages from his correspondence with the Board of Works on the matters connected with Buckingham House, which, as far as regards the defects of that structure as a State Palace, relieve him of the blame, and throw it upon Royal shoulders. It is a curious piece of autobiography, and a farther

proof, if any were wanting, that amateur architects (although they even be Royal) generally produce monstrosities. If Michael Angelo had had a George the Fourth for a patron, Rome_would not have been able to boast of St. Peter's.

"His late Majesty's intentions and commands were to convert Buckingham House into a private residence for himself. A plan was made upon a small scale, merely adding a few rooms to the old house. Whilst this plan was forming, and on my observing that the plan was being enlarged, I continually urged his Majesty to build in some other situation, and made several plans for that purpose, using all the arguments in my power to dissuade his Majesty from adding to the old Palace, but without any effect; for the late King constantly persisted that he would not build a new Palace, but would add to the present house. I then urged his Majesty to pull down the house, and rebuild it higher up in the garden in a line with PallMall. To induce his Majesty's acquiescence, I stated the lowness of the present site and the northern aspect, and recommended that the house should be placed on a level with Hyde Park Corner, and in a line with PallMall, a road or prolongation of which should cross the Green Park as an approach. This proposition I thought had some weight, and for a time I had hopes my recommendation would be adopted; but one day, either at Buckingham House or Kensington, his Majesty took me to Lord Farnborough, and said, good-humouredly, Long, now remember I tell Nash before you at his peril, ever to advise me to build a palace. I am too old to build a palace. If the public wish to have a palace, I have no objection to build one, but I must have a pied à terre. I do not like Carlton House standing in a street; and, moreover, I tell him I will have it at Buckingham House; and if he pulls it down he shall rebuild it in the same place; there are early associations which endear me to the spot.' Such were nearly the words that passed. From that moment I never presumed to press his Majesty on the subject of building a palace, or of removing the site.

Plans

were accordingly made, and, with a rough estimate, submitted to Lord Liverpool. Before they were decided upon, very considerable additions were commanded, and further estimates, until at length the plans, nearly as they now are, were completed and approved, and I was directed to carry them into execution. The building being so enlarged, and additions being daily suggested, I began to think the King might be induced to make use of it as a State Palace, and I frequently expressed my fears to his Majesty; but he persisted in saying, that he should continue

to hold his Courts at St. James's, and that he never would hold them at Buckingham House. After the building was covered in, his Majesty sent for me to Carlton House, and said, Nash, the State rooms you have made me are so handsome, that I think I shall hold my Courts there.' I took the liberty to submit to his Majesty how unfair such a determination was to me as an architect; that the building was not arranged in a manner suitable to a State Palace; that no provision was made for the establishment of a Queen, nor for the office of the Lord Chamberlain or the Lord Steward. To these he replied, 'You know nothing about the matter; it will make an excellent palace, and Lord St. Helen's and myself have arranged the use of the several apartments.' This arrangement his Majesty then explained, and I pointed out the objections as they occurred to me, all of which he overruled, saying, 'Lord St. Helen's and I have arranged all that.' This explanation, which can be confirmed by Lord Farnborough, Lord St. Helen's, and Sir William Knighton, may, I trust, protect my plans from the observations which must other. wise result from the Lord Chamberlain's and Lord Steward's reports. His Majesty never contemplated the Lord Steward's or Lord Chamberlain's establishments at Buckingham Palace; and when I mentioned the necessity of taking down St. James's Palace, in order to carry the Parliamentary plan of improvement in St. James's Park into effect, I stated the necessity of providing for the Lord Chamberlain's and Lord Steward's offices. I trust this statement will be a sufficient justification against any remarks that may be made to my prejudice respecting the fitness of the plan for a State Palace. The paucity of light that has been complained of in part of the basement story, was occasioned by his late Majesty not wishing to have any of the windows of the servants' room overlooking the Terrace; and covered areas were substituted for the gardens proposed by me on a level with the basement; but the ground may be easily removed and these lights restored.

"The appropriation of the apartments in the basement story was settled with the different officers who were to occupy them; any observations, therefore, that are applicable to this part of the plan, are answered by the circumstance, that they were suggested, made, and approved by the late King, for whose use the Palace was planned, and neither I nor any one else can be blamed, if they do not suit the present establishment.

"To the objections to the light of the gallery, I beg to answer that the late Sir Thomas Lawrence was consulted by me, and expressed his approbation; that other galleries for works of art which have been fre

quently praised on account of the distribubution of light, are lighted in the same manner; the only objection that can be urged against it is, that the light being so close to the walls, the projection of very deep frames may cast a shadow on the upper part of the pictures; but a row of circular lights is made in the centre of the ceiling, although at present closed, which, if opened, would disperse the shadow cast by the frames, and then, I trust, the alleged defect will be remedied."

In defending his work from the charge of insecurity which had been brought against it, and in proof of which he said the Committee only brought forward opinions, not facts, he refers to works which he had effected "of great practical difficulty, both in construction and execution.'

"In enumerating a few of those works of difficult construction and execution which have accomplished, I shall do little more than name them, as I regret the necessity of ap. pealing to them at all. One of the first works of this kind was the restoration of St. David's Cathedral; the west front wall, 70 feet high and 10 feet thick, had for half a century overhung its base, and which had been continually increasing, and was plumbed every year, and its progress towards falling marked down. At the time I was called upon by the Chapter to examine it, the top overhung the base 44 feet; the Saxon arches on each side of the centre aisle, all the way to the choir, leaned against this wall, and which was their only support, inasmuch that, had it fallen, the whole of the church as far as the choir must have fallen with it. I constructed a timber buttress on a temporary foundation, and supported the whole of the Saxon arches; I then took down the wall from top to bottom, prepared a new foundation, and rebuilt the wall upright, encased the temporary buttress with stone, and substituted stone arches for the wooden buttress. During which operation not the slightest accident happened; and though this work has been done 45 years, not the slightest settlement has taken place, and it is a perfect work at this day.

"When Sunderland Bridge was to be built, I was employed to make designs and estimates for a stone arch of 300 feet diameter; the practicability of which was denied by those who objected to any bridge being built at all, and a violent party contest took place between those who projected and those who opposed the bridge, and a Committee of the House of Commons of that day were selected to decide the question of bridge or no bridge. The party opposing denied the practicability of executing a stone arch of that

size; and to support their opinions, Dr. Hutton, Mathematical Professor at Woolwich, Mr. Smeaton, who built the Edystone Lighthouse, and Mr. Mylne, who built Blackfriars Bridge, were called in, and examined before the Committee.

"They rested the impracticability of the measure on the circumstance that so vast a structure in stone required a very different process in every part from that required for bridges of the largest size that ever had been built. To combat the opinions that I knew would be given by those three eminent men, I had recourse to the making a model of a very large size, together with the machinery and contrivances necessary to meet every difficulty which should be proposed, and establish the practicability of the arch.

"The model was produced before the Committee. Mr. Mylne insisted on his experience to state at once, without examination of the model, that it was impracticable. Mr. Smeaton declared, that he never denied the practicability, but that, on the contrary, he could build a bridge from Dover to Calais; that no doubt the model 1 produced could be executed, but that no one could calculate the expense. Dr. Hutton admitted the practicability, but recommended a catenarian arch in preference to a circular one. The result was, that the model was approved in all its parts, and the Bill passed.

"On account of the stone arch, the present iron one was adopted, formed from the model at that time exhibiting by Tom Paine; but such was the effect of the investigation, that I had frequent invitations to form piers, docks, and other works, exclusively the province of engineers.

"The late Mr. Rennie pressed me to give a design for building London Bridge, offering me the use of his survey and section of the river.

"When the tunnel under Highgate-hill, designed by the late Mr. John Rennie, fell in, I was called upon to ascertain the cause, and suggest the remedy. I removed the whole of the tunnel, supported the ground for the depth of 80 feet, and built the present archway. The difficulties which were encountered in these operations would hardly, if detailed, be credited.

"The late Mr. Rennie, in his pamphlet addressed to the Commissioners of Sewers on the subject of substituting a new common sewer to drain the west end of the town (the old one being decayed and inadequate), suggested a tunnelled sewer, but doubted its practicability without taking down a great number of houses.

"That sewer I effected, and made the tunnelled sewer, without taking down or injuring a single house. In a Committee of the House of Commons, engineers were brought to op