1847.] 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



153 



prolect it. The inner and outer bands of iron are Ihe portions of ilie valve 

 on which Ihe wheels act in opening and closing it. The whole valve is 

 lifted out of its seat by Ihe inner wheels during the passage of the piston, 

 and is again replaced in it by one of Ihe outer wheels. It was staled that 

 Ihe specification had been enrolltd in October last. 



S. " Improvements in Railway Carriages." By Mr. Jamcs Wight. 



Mr. Wight exhibited a full sized drawing of his proposed carriage 

 wheels, having Ihe lire at an angle of 45 degrees to the rails, entirely ob- 

 viating Ihe rubbing and shearing friction of the present wheels, while the 

 load is suslsined by the second set of spokes converging at Ihe upper jour- 

 nal of Ihe axle, perpendicular to the rail. His proposed conical form re- 

 quisite for the periphery of the driving wheels was also exhibited, adapting 

 tbemselves to ihe curves o\er which they pass, and moving freely round 

 without any slipping of Ihe w heels, or twisting of the axles, resulting from 

 their present form ; and entirely dispensiug with Ihe clumsy artifice of 

 watering the rails from Ihe locomotive, designed to assist their sliding when 

 compassing a curve, — a properly Ihe reverse of which is of Ihe utmost ini- 

 porlance to Ihe uliliiy of the locomotive. He also suggested an improve- 

 ment in Ihe mode of traction, by appending the drag hook at Ihe head of a 

 single buffer rod issuing from the centre of each carriage, in place of one 

 from each side as at present, Ihe end of each rod being made to compre- 

 hend two convex springs, which are placed under the centre of Ihe carriage, 

 so that eilher in the traction or propulsion they are compressed simulta- 

 neously, and Ihe concussion is sustained at Ihe centre of Ihe carriages with- 

 out the slightest tendency to throw Ihera olT the rails. 



April 12. — George Tait, Esq., V.P., in the Chair. 



The following communications were made: — 



1. " New Method of Ventilating Public Buildings, Churches, Schools, 

 Dwelling-houses, &c., by means of Hot-Water apparatus placed at Ihe 

 roof of the building, for extracting Ihe exhaled air ;" — successfully em- 

 ployed to ventilate various buildings. Designed and applied by I\lr. Ko- 

 BERT Ritchie. 



Mr. Ritchie gave a short account of the methods which have been 

 usually employed in ventilating buildings, and showed that, as the object 

 was to induce a current from a difl'erence in temperature, the plan he had 

 in previous communications suggested (18J3-4), of making use of the heat 

 from hot water or steam, all'orded a safe and efficient medium for extract- 

 ing the exhaled air from aparlmenls. He had since had several opportu- 

 nities of carrying his views into eO'ect in large buildings, and the result has 

 been quite successful. He then described Ihe method he had adopted at 

 the .Justiciary Court-house, Glasgow, and elsewhere. A powerful hot- 

 water apparatus of patent tubes — laised to a high heat, and supplying 

 themselves with water — is placed in a small chamber at the roof, and is 

 heated by a furnace placed at the basement of the building. The appara- 

 tus acts as an artificial fire, and from the rarefaction of the air within the 

 chamber the exhaled air from the apartment to he ventilated is drawn to- 

 wards it, through the ventiducts formed over the ceiling, and rises or is 

 expelled through an elevated ciiinmey or shaft into the atmosphere — Ihe 

 healed current being protected from Ihe actiuu of the wind by means of 

 turncaps or screens. 



Mr. Ritchie showed the arrangements he had provided for the regulation 

 or control over Ihe velocity or movement of the air in the room. He 

 pointed out, amongst other advantages of this mode of ventilation, that it 

 was free from all risk of fire, as Ihe furnace might be 50 or more feet from 

 tiie heated chamber at the roof; that the air within ihis chamber admitted 

 of simple means of increase ; that there was no risk of ihe relhix of the 

 exhaled vapours, and, even were it so, these could, by no possible means, 

 be mixed with the products of the combustion of luel : that ihe apparatus 

 was simply managed, and the expense not greater than other plans in use. 

 He likewise showed the necessity of combining, with every plan for ex- 

 tracting the exhaled air, an adequate supply of fresh air — that buildings, 

 whether heated wilh or without open fires, should have the means afl'orded 

 for obiaining a continued supply of moderately warmed air in winter, to 

 replace ihat which is vitiated by respiration and gas, or which goes off by 

 chimneys. He showed the plan he had adopted for warming the Court- 

 house, Glasgow, and the Commercial Bank, Edinburgh, wilh simple hot- 

 water apparatus, which afford supplies of fresh air, duly regulated in lein- 

 perature and humidity. He concluded with pointing out that the princi- 

 ple of Ihe ventilation described was equally applicable to domestic as to 

 public buildings ; that a great many rooms might be ventilated with the 

 same hot-water apparatus placed at the roof, and healed at the basement ; 

 that the architect (W. Nixon, Esq.) fur Ihe New Police Buildings, Edin- 

 burgh, had adopted this plan for extracting the exhaled air from the cells 

 and other rooms; that whole teuements (so important to salubrity) might 

 thus be ventilated ; for the capabilities of the patent screw joint apparatus 

 was such, when combined witli the ingenious systems of continuous circu- 

 lations, that as much 6000 feet of pipe can be heated with one small lire. 



2. " Improved Chimney Cans or Fund- Expulsors," for the Cure of Smoke 

 and Blow-downs in Chimneys. By Mr. James Stewart, jun. 



The principle on which these chimney-cans are invented, is to prevent 

 the inconvenience of smoke being sent back into aparlmenls by high winds 



or by change of wind ; and to have the construction of Ihe chimney-cans 

 such as to improve the draught, and to present no obstacle to ihe free 

 egress of the smoke, nor to the cleaning of the vent; while, in ordinary 

 circumstances, no undue accumulation of soot can possibly arise. The 

 cans being stationary, are less liable to go out of order than the moveable 

 ones in common use. Mr. Stewart stated that their operation had been 

 quite successful, and Ihat they bad cured of smoke rooms which before 

 had scarely been habitable. These cans can be made in galvanised iron 

 from 23s. to 303, or in clay for 10s. Od. The valve is fixed on the chim- 

 ney-top or can, to prevent back smoke or down-draught, and is operated 

 upon by a wire or chain from the fire-place. 



3. " Self-acting Cart-Drag or Break," which is worked by the Horse 

 Itself. By William Rutherford, laud-steward lo Ihe right honourable 

 Lord Douglas. 



This break can be fitted up on any two-wheeled cart or coach, with 

 shafts, at a very moderate expense, from the simplicity of its machinery. 

 It consists only of the following parts :— Two wooden rubbers, applied 

 in front to the rims of the wheels, are connected wilh each end of a cross- 

 bar of malleable iron, 1^ inches deep and J of an inch thick, placed at 

 right angles to the shafts, and horizontally, below the body of the cart in 

 front of the wheels. This cross-bar is held in its place by keepers of iron 

 attached to the outside of each shaft, leaving abont 3^ inches of space for 

 ihe crossbar to move backwards and forwards, so that tlie rubber may be 

 easily withdrawn from or applied to the wheels. To the cross-bar are 

 attached two iron rods, Jths of an inch in diameter, running each below a 

 shaft, and parallel lo each other. Two keepers retain each rod below its 

 shafi, and allow it to move freely backwards and forwards. A hook is 

 attached lo each rod about two inches from their ends, so that when Ihe 

 horse is yoked by the shoulder and back-chains in the usual way, the back- 

 chains are attached lo Ihe hooks. The horse has thus Ihe power, when 

 urged by the load behind, on a steep incline, to press back Ihe rubbers 

 upon the wheels, and retard their progress to any extent desirable. When 

 the rubbers are not required to act, such as when the horse is pulling for- 

 ward on a level, or going up an incline, the break is kept from touching 

 the wheels by a spring fixed behind the cross bar to which the rubbers are 

 atiached, and pressing that bar forward. Finally, two small keepers and 

 hooks, at the euds of the rods, are used for Ihe purpose of preventing their 

 motion when backing the cart. 



4. " A new Regulating Index for the Pendulum." By Mr. James 

 M'Ewan, watchmaker. 



The bob of the pendulum is made in two halves, being hollowed in the 

 centre, so as to admit a contrale wheel, carrying on its arbor an index-hand 

 which points on a dial-plate in front of the bob to Ihe words fast or slow ; 

 the nut at the bottom of the pendulum being turned, it acts on Ihe wheel by 

 a pinion, and thus any person who has occasion to regulate Ihe beat of Ihe 

 pendulum can see by the index-hand how far he raises or lowers the bob. 

 Of course, Mr. M'Ewau intends this merely for common domestic clocks, 

 and not for tine time-keepers, whose rate would be afi'ected by the mere 

 motion of the index-hand round the dial-plate of the bob. 



5. " An Alveolar Hemorrhage Compress," for suppressing undue Bleed- 

 ing, resulting from the Extraction of Teeth, constructed by Dr. Robert 

 Reid, dentist, was exhibited. 



0. Specimens were exhibited of Mrs. H. Marshall's " Patent Intonacn 

 Cement," the inventor slating that although only half-an-iuch thick upon 

 the lath, its capabilities of resisting fire were very great, and indeed, might 

 be subjected to a trial by fire for a considerable time, while the lath bshind 

 it, and in contact with it, would scarcely be singed. 



A ist of Prizes to be olfered for Session 1847 8 was submitted by the 

 Council and approved of, and ordered to be printed and advertised as 

 usual. (See Advertisement.) 



SOCIETY OF ARTS, LONDON. 



7)7ar<;A31— Wm. Pole, Esq., F.K.S., V.P., in the Chair. 



M. RiCABDO, Esq., gave an account of his " Indicator for ascertaining 

 the Speed of Railway Trains." The machine consists of a pair of govern- 

 ors, lo which motion is given by means of a band working on a horizontal 

 wheel, attached to one of the carriages ; as the speed of the train increases, 

 the governors fly open and pull round a hand, which points out, on a gra- 

 duated dial, the number of miles per hour at which the train is travelling. 

 The governors are prevented from fljing open with a jerk by two pieces of 

 vulcanized iudiarubber, which lengthen gradually as the speed of the 

 train increases. 



The Secretary read a paper by Mr. T. R. Crampton, " Ou the working 

 oj his large-wheel narrow gauge Locomotive Engine, the ' Namur,'" for the 

 design for which he last session received the Society's Gold Isis Medal. — 

 The author having made some remarks on the statement put forth by him 

 last year, as to the advantages posses.sed by an engine built on his princi- 

 ple over those on the old plan, proceeds to give the following account of 

 the Namur: — 



21 



