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THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[December, 



We add some measurements of ancient seats, taken from several counties, 

 which will probably be serviceable to many of our readers. We would call 

 attention to the remarkable uniformity of proportion which generally charac- 

 terises those of the same kind. Indeed it would be useless to multiply exam- 

 ples to a great extent, since any important difference from the above ad- 

 measurements must be regarded as an exception. In conclusion, we would 

 urge all who are about to replace open seats in their churches to follow faith- 

 fully ancient models, which are. happily, even yet sufficiently abundant in our 

 parish churches. — Ecclesiologist. 



PROCEEDINGS OF SCIENTIFIC SOCIETIES. 



INSTITUTION OF CIVIL ENGINEERS. 

 June 13. — The President in the Chair. 



" Description of a Plan, adopted for carrying off an accumulation of 

 Water front the TJ'arehouses, Cellars, 6fC, near the Wet Dock at the Port of 

 Ipswich." By George Hurwood, Assoc. Inst. C. E. 



The paper states that in consequence of the formation of the wet dock at 

 Ipswich, the water from the land-springs, which was formerly carried away 

 by the river, accumulated to such an extent, as to cause serious inconve- 

 nience to the owners of the warehouses, cellars, &c, many of them being 

 beneath the level of the ordinary tides. It was difficult to find a remedy for 

 this, as nearly the whole of the line, affected by the water, was at so low a 

 level, that a discharge could only be effected at the lowest ebb of the tide, 

 and a general sewer could not have been constructed at a moderate expense, 

 because from the lowness of the level, water would have accumulated con- 

 stantly in it, and any casual increase from rain or other causes, would have 

 been sufficient to inundate the adjoining buildings. 



The plan designed by the author, and which has been executed, had for 

 its object, the construction of a sewer which should drain these buildings 

 alone, and at the ebb tide should carry off the accumulated water, being at 

 the same time of sufficient size to contain the water, which was prevented 

 from being discharged by the flowing tide. It was required therefore to be 

 water-tight, and branch drains were necessary from all the points where 

 water penetrated. 



To insure the success of the plan, every precaution was taken for pre- 

 venting the influence of the tide in the general sewer, retarding the discharge 

 or operating upon the lateral sewers. 



At the end of the main sewer was placed a cast-iron frame, upon which 

 were hung three tide-flaps with brass facings, accurately fitted, and balanced 

 by levers and counterweights. By this means the water was discharged at 

 any height, and without any considerable head of water being required to 

 open the flaps. Each cellar was connected with the main drain by an iron 

 pipe, with a well-balanced valve at its end, so that the water could have an 

 easy exit ; but as soon as any accumulation within the sewer occurred, the 

 valves closed. 



The sewers were built of brick, in mortar made from blue lias lime. The 

 dimensions varied from 12 inches to 21 inches in diameter, and the cost of 

 the latter size was 12s. $d. per yard, including excavating, laying, filling, &c. 



The plan is stated to have proved very successful, and as particular regu- 

 lations are enforced, to prevent any admission to the sewers, of other than 

 the water which filter through the natural strata of the chalk. basin, the 

 water in the sewers is fit for domestic or manufacturing purposes. 



The communication is illustrated by a drawing, showing the situation of 

 the town and dock of Ipswich, with the extent of the lines of sewers, and 

 the details of their construction, and that of the tide and other flaps. 



" On the Formation of Embankments for Reservoirs to retain Water." 

 By Robert Thorn, M. Inst. C. E. 



After describing a model, designed to show that the proper slope for reser- 

 voir embankments, should not be less than three to one on the water-face, 

 and remarking that waves act more severely on the pitching or paving of the 

 inner face, in proportion to the steepness of the slope, the author proceeds 

 to describe in detail the mode of forming embankments. The foundation is 

 excavated to such a depth as is found firm and capable of preventing the 

 passage of water, then spreading alternate layers of puddled peat, or alluvial 

 earth and gravel, and beating them together with wooden dumpers, until 

 they are completely mixed ; the slopes are covered with a puddle made with 

 small stones or furnace-cinders mixed with clay, so as to prevent the possi- 

 bility of moles or other vermin penetrating into the embankment. He con- 

 demns the practice of forming embankments with puddle-trenches, and refers 

 to many reservoirs made by him at Greenock, Paisley, and elsewhere, the banks 

 of which have stood the test of time without having any puddle-trenches in 

 them, and particularly mentions one at Greenock which remained firm and 

 sound, after a rush of water passing over it at a height of ten feet, caused 

 by the breaking down of the embankment of a reservoir situated about ISO 

 yaids above it. He recommends, instead of the puddle-trenches, that the 

 whole of the inner part of the embankment should be made water-tight 



during the formation of it, by which means it will more effectually resist 

 either any casual injury, or any effect of the swelling of the puddle-trench. 

 The paper is entirely of a practical nature, and is intended to illustrate the 

 author's peculiar views founded on his long experience. It is accompanied 

 by a diagram of the model used in his experiments. 



June 20. — The President in the Chair. 



A Pressure- Gauge was presented for the Museum of the Institution by 

 Alfred King, M. Inst. C. E. 



This gauge, which has been used at the Liverpool gas-works for more than 

 ten years, for indicating small amounts of pressure, consists of a close cistern 

 containing water, in which is a cylinder having in it a hollow float, connected 

 with a balance-weight, by a fine silken cord, passing over a pulley, on the 

 axis of which is fastened a pointer, one end of which marks the amount of 

 pressure upon a dial divided in such a manner, that as each division is equal 

 to a column of water of -^th of an inch, a difference equal to ^yh, or 

 even -nnyth of an inch, may be estimated. 



The action is very simple, the float being elevated by the rising of the 

 water within the cylinder, when the surface is depressed in the cistern by the 

 pressure of the current of gas from the inlet pipe. 



The description was illustrated by a diagram showing the interna! con- 

 struction of the gauge. 



" Description of a Machine for raising and loxccring Miners." Bv John 

 Taylor, M. Inst. C. E. 



The author states that the great depth in which the copper and tin mines, 

 in Cornwall, and in Germany, had been worked, had drawn simultaneously 

 in the two countries, the attention of engineers to some mode of facilitating 

 the ascent and descent of the miners, whose strength was exhausted, and 

 their health seriously affected, by the fatigue of going to and returning from 

 the scene of their labours by nearly vertical ladders, as the men could not be 

 raised and lowered by the rope of the winding engines, as in the coal dis- 

 tricts. The Polytechnic Society of Cornwall offered premiums for machines 

 for effecting this object, and in 18.14 three prizes were respectively awarded 

 to Mr. Michael Loam, Capt. \V. Nicholas, and Capt. W. Richards for plans, 

 the two first of which embraced the principle which has since been adopted 

 with modifications, both in Germany and in Cornwall. A premium was also 

 offered by Mr. Tremayne for any new method, or for the most available im- 

 provement on the former plans, and was awarded in 1838 to Mr. John Phil- 

 lips for a method, differing, however, from that which has been put in prac- 

 tice. About this time it was ascertained that a machine, somewhat similar 

 to that designed by Mr. Michael Loam, had been applied with success to one 

 of the deepest mines in the llartz; and drawings, with a description, were 

 published in the Report of the Polytechnic Society of 1838. Mr. Charles 

 Fox also commenced a subscription, for the purpose of awaiding a sum of 

 money to any proprietor of mines, who would first bring into active opera- 

 tion, efficient machinery adapted for the purpose in question. 



At length the adventurers of the Tresavean copper-mines, undertook to 

 erect a machine from the designs, and under the superintendence of Mr. 

 Michael Loam : it was first used for a depth of 27 fathoms, on the 5th of 

 January, 1842; has since been extended to 204 fathoms; and it is now con- 

 templated to carry it to the lowest part of the mines, which is 288 fathoms 

 deep. 



The machine, which is worked by a steam-engine, with a cylinder of 36 

 inches diameter, consists of two rods, to which are attached, at intervals of 

 6 feet throughout their length, platforms upon which the men stand : these 

 rods receive an alternating motion from two cranks, which give them a 

 stroke of 12 feet ; the men, either in ascending or descending, step from one 

 platform to the other, as the rods remain fur an instant almost stationary, 

 when the cranks are going over top and bottom centres; and as the plat- 

 forms are half the length of the stroke apart, one set of men can ascend 

 while another set is descending, without at all interfering with each other. 

 Each rod makes three strokes per minute ; and when once the platforms are 

 filled with men, they are landed at the rate of six men per minute, either 

 going up or down ; the speed of travelling being about 72 feet per minute, 

 or 240 fathoms in 20 minutes. By the ordinary mode of ascending by lad- 

 ders it would have occupied 48 minutes to mount from the same depth, as 

 the usual speed is about 30 feet per minute, so that more than 50 per cent, 

 of time is saved, independent of the diminution of fatigue. 



The rods at the Tresavean mine act vertically for the first 70 fathoms, 

 below which they follow the direction of the vein, diverging from the per- 

 pendicular from 6 inches to 18 inches in 6 feet. The action of the ap- 

 paratus is stated to be perfectly successful ; no accident has occurred in the 

 use of it, and the miners are convinced of the safety as well as the ease 

 afforded by it. 



The paper is illustrated by two drawings by G. B. W. Jackson, Grad. Inst. 

 C. E., showing the details of the machine; they are copied by permission of 

 Sir Henry De la Beche, from the model now in the Museum of Economic 

 Geology. 



Remarks. — Mr. Taylor observed, that there was an extraordinary coinci- 

 dence of time in the appearance of this invention, as the public attention, 



