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For particulars and details； see Report of Torpedo Committee。
1839。 A Double…faced Wedge…shaped Sluice…Valve for Main Street Water…pipes。
The late Mr。 Wicksteed； engineer of the East London Water Company； having stated to me the inconvenience which had been experienced from the defects in respect of water…tightness； as well as the difficulty of opening and closing the valves of the main water…pipes in the streets； I turned my attention to the subject。 The result was my contrivance of a double…faced wedge…shaped sluice…valve； which combined the desirable property of perfect water…tightness with ease of opening and closing the valve。
This was effected by a screw which raised the valve from its bearings at the first partial turn of the screw； after which there was no further resistance or friction； except the trifling friction of the screw in its nut on the upper part of the sluice…valve。 When screwed down again； it closed simultaneously the end of the entrance pipe and that of the exit pipe attached to the valve case in the most effective manner。
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Mr。 Wicksteed was so much pleased with the simplicity and efficiency of this valve that he had it applied to all the main pipes of his Company。 When its advantages became known； I received many orders from other water companies； and the valves have since come into general use。 The prefixed figure will convey a clear idea of the construction。 The wedge form of the double…faced valve is conspicuous as the characteristic feature of the arrangement。* ＇footnote。。。 At a meeting of the Institution of Civil Engineers； May 23； 1883； when various papers were read on Waterworks； Mr。 H。 I。 Marten observed in the course of the discussion： 〃It has been stated in Mr。 Gamble's paper （on the waterworks of Port Elizabeth） that the sluice valves are of the usual pattern。 The usual patterns of the present day are in wonderful advance of those of thirty or forty years since。 The great improvement originated with the introduction of 'the double…faced sluice…cock。' This sluice…cock； which had now superseded every other description； was the creation of Mr。 James Nasmyth's inventive genius。 Mr。 Marten said he well remembered the first reception of this useful invention； as he happened at that time to be a pupil of Mr。 Thomas Wicksteed。 He was present when Mr。 Wicksteed explained to Mr。 Nasmyth the want he had experienced of a sluice…cock for Waterworks purposes； which should shut and remain perfectly tight against a pressure coming from either side。 Mr。 Marten had a lively recollection of the instantaneous rapidity with which Mr。 Nasmyth not only grasped but provided for the requirement； so that almost by the time Mr。 Wicksteed had completed the statement of his want； Mr。 Nasmyth had drawn upon the back of an old letter a rough sketch of the first double…faced sluice…cock； and in less than an hour had converted this rough sketch into a full…sized working drawing； in the preparation of which it fell to Mr。 Marten's lot to have the honour to assist。 In his 'Autobiography' Mr。 Nasmyth referred to the conversation with Mr。 Wicksteed； and introduced a print of the drawing made upon the occasion。 The invention has been of the greatest use to the Waterworks Engineer； especially in connection with the constant supply system； in which it frequently happened that the pressure was sometimes against one face of the sluice…cock； and sometimes against the other。〃 See Proceedings and Discussions of the Institution of Civil Engineers； 1883； pp。 88； 89。 。。。＇
1839。 A Hydraulic Mattress Press； capable of exerting a pressure of Twenty thousand tons。
Being under the impression that there are many processes in the manufacturing arts； in which a perfectly controllable compressing power of vast potency might be serviceable； I many years ago prepared a design of an apparatus of a very simple and easily executed kind； which would supply such a desideratum。 It was possessed of a range of compressing or squeezing power； which far surpassed anything of the kind that had been invented。 As above said； it was perfectly controllable； so as either to yield the most gentle pressure； or to possess the power of compressing to upwards of twenty thousand tons； the only limit to its power being in the materials employed in its construction。
The principle of this enormously powerful compressing machine is similar to that of the Hydraulic Press； the difference consisting principally in the substitution of what I term a Hydraulic Mattress in place of the cylinder and ram of the ordinary hydraulic press。 The Hydraulic Mattress consists of a square or circular water…tight vessel or flat bag formed of 1/2…inch thick iron or steel plates securely riveted together； its dimensions being； say 15 feet square by 3 feet deep； and having semicircular sides； which form enables the upper flat part of the Mattress to rise say to the extent of 6 inches； without any injury to the riveted joints； as such a rise or alteration of the normal form of the semicircular sides would be perfectly harmless； and not exceed their capability of returning to their normal curve when the 6…inch rise was no longer necessary； and the elevating pressure removed。
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The action of this gigantic press is as follows。 The Mattress A A having been filled with water； an additional quantity is supplied by a force pump； capable of forcing in water with a pressure of one ton to the square inch； thus acting on an available surface of at least 144 square feet surfacenamely； that of the upper flat surface of the Mattress。 It will be forced up by no less a pressure than twenty thousand tons； and transfer that enormous pressure to any article that is placed between the rising table of the press and the upper table。 When any object less thick than the normal space is required to receive the pressure； the spare space must be filled with a suitable set of iron flat blocks； so as to subject the article to be pressed to the requisite power。
As before stated； there may be many processes in the manufacturing arts in which such an enormous pressure may be useful； and this can be accomplished with perfect ease and certainty。 I trust that this account of the principles and construction of such a machine may suggest some employment worthy of its powers。 In the general use of the Mattress press； it would be best to supply the pressure water from an accumulator； which should be kept constantly full by the action of suitable pumps worked by a small steam…engine。 The great press would require the high…pressure water only now and then； so that it would not be necessary to wait for the small pump to supply the pressure water when the Mattress was required to be in action。
1840。 A Tapping Square； or instrument by which Perfect Verticality of the Tapping of Screwed Holes is insured。
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The letter X shows how Screws are frequently made when tapped in the old mode； the letter T as they are always made when the Tapping Square is employed。
1840。 A Mode of turning Segmental Work in the Ordinary Lathe
In executing an order for twenty locomotive engines for the Great Western Railway Company； there was necessarily a repet