368 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



[DeCEltBCB, 



Analysis of Merchandise Traffic. 



BEGISTSR OF NEW PATXiVfTS. 



GAS-METERS. 



Samuel Clegq, of 2t, Regent-square, London, civil engineer, 

 for " certain improi^emerits in gas-meters." — Granted April 20 ; En- 

 rolled October 20, 1848. 



Tlie patentee claims, in this invention, the dividing of the gas 

 ishich passes through a meter into two or more portions, and ascer- 

 taining the whole quantity by measuring a part when under pres- 

 sure.instead of measuring all the gas whichpassesthroughthe meter. 

 Another portion of tlie invention claimed as new, is the making of 

 the inner circle of the drum of a water-meter water-tight, that 

 being in water it may be buoyant, and prevent the weiglit of the 

 drum from pressing upon the axis. The principle on which the 

 first part of this invention depends, is the well known law, that 

 the discharges of the same Huid through diiferent openings at the 

 same i)ressure are proportional to the areas of the openings. The 

 arrangement of the apparatus is as follows : — The measuring-drum 

 of a wet meter consists of a hollow concentric ring aud cover. 



The drum, revolving upon an axis in water, is divided into com- 

 partments so arranged that, as the gas enters, it sliall in succes- 

 sion fill all the chambers, and be discharged measured. The inner 

 circle c, c, of the drum is made water-tight, so that when the 

 meter is filled to a certain level with water, the drum is buoyed 

 up, and would nearly float if otherwise unsupported ; con.sequently, 

 there is little or no friction upon the axis. The gas from the service 

 enters the meter-case through the pipe k, and after passing a 

 valve, — which, when the meter is sufficiently filled with water, is 

 opened by a float in the usual way, — is divided into two streams, 

 and flows through the pipes c and b', the latter stream being the 

 one measured, and is discharged so measured from the drum-cover 

 by the pipe p, through the opening n. Now this discharge being 

 known, the quantity of gas that passes through the other opening 

 M, is known also, and the sum of the two discharges is marked on 

 the face of an index arranged in the usual way. 



To equalise the pressure, the following apparatus is used : E and 

 H, are two hollow vessels connected with one another at their 

 lower parts, open at the bottom, sealed by water, and free to 

 vibrate about a common centre x ; v is a slide, covering the two 



openings si and n, attached to the hood ii, in such a manner that, 

 as it rises or falls, it shall move the slide v, and open or close 

 these openings. The pi])es a and b, lead into these vessels or 

 hoods, and the gas discharged into them is of the same pressure 

 as that which flows into the meter ; so that, if the regulating-hoods 

 were of the same weight, and at equal distances on each side of 

 the centre .v, they would balance each other. Over the hood E, 

 is fixed immovealily aiKjther and larger vessel c, o])cn at the 

 bottom and sealed by water, having communication with the drum 

 of the meter, or rather with the drum-cover at k. The openings 

 M and N, adjusted by the movement of the hood "i nre by its 

 descent partially closed, and the pressure of the gas flowing 

 through them is reduced by so much as exists between the gas 

 flowing into the meter-drum through the i)ipe b', or the initial 

 pressure, — or that between the interior or exterior surfaces of the 

 hood E, viz., one-tenth ; so that the gas now flows through both 

 openings, m and n, with the same relative velocities, the discharges 

 being in proportion to their areas. 



Supposing that the measuring-drum required a pressure of two- 

 tenths head of water to work it, and that the initial pressure was 

 four-tenths, the pressure in the cover of the drum and in the fixed 

 hood o, will then be two-tenths. The gas will issue from the 

 opening n, with a pressure also of two-tenths ; and the differences 

 of pressure between the interior of the hoods E and h, and the 

 exterior of the hood e, being two-tentlis, the hood ii, will have a 

 descending power of two- tenths, and thus the velocities with which 

 the gas issues through m and n, will be equalised ; and so for any 

 other pressure. The same principle of measurement may be ap- 

 plied to dry meters. 



TUBULAR FLUES. 



Thomas Potts, of Birmingham, brass tube maker, for " improve- 

 ments in the manufacture of tubular flues of locomotive and other steam- 

 boilers." — Granted April 10; Enrolled October 10, 1848. 



The object of this invention is to protect the flues of boilers, by 

 lining them with a composition resembling that used for brazing. 

 In forming this material, ten ounces of refined tin are added to a 

 hundredweight of " bath metal," which is composed of two parts 

 of foreign zinc and three parts of good copper. This compound 

 metal is rolled and formed into a ttibular shape of the size re- 

 quired ; after which, the tubes are annealed and stretched, so as 

 to straighten them and bring the edges correctly together. On 

 each of these tubes is placed a tube formed of copper or an alloy 

 of cop])er ; and the compound tube is jiut on to a steel mandril, 

 made with a taper of about one-sixteenth of an inch into its whole 

 length, which not only facilitates the withdrawal of the mandril, 

 but also gives additional thickness to that end of the tubular flue 

 which is to be fixed to the fire-box of the steam-boiler. The com- 

 pound tubes, each having a mandril within them, are then drawn 

 through draw-plates. It is not necessary to solder together the 

 edges of the inner tube, as it will be sufl[iciently strong without. 

 The lining should be made twice as thick as the outer tube. 



The patentee claims the use of a lining of such a preparation 

 of metal, for lining tul)ular flues of copper and of copper alloyed ; 

 the object being to obtain a lining of metal which shall be less 

 prejudiciidly acted on by the passage of sharp grit from the fire, 

 than if the whole tube were made of copper or of copper alloyed. 



