184,8.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



BUNNETT'S SEWER TRAP. 



j\lr. Biuinett, of the lii-m of Bunnett and Corpe, of Lombard- 

 street, has invented a ^'ery simple and cheap " Self-acting Effluvia 

 Trap" which differs from all previous contrivances. The fault of 

 the old invention was that they were so arranged that a very small 

 quantity of water caused the pan of the trap to fall, and conse- 

 quently during a shower of rain, or water falling upon it, the 

 action was intermittent, continually opening a communication witli 

 the sewer, and lialde to lie held open permanently by any light 

 matter being caught by the rising of tlie pan. In Mr. Bunnett's 

 improved trap this is avoided by introducing a peculiar mechanical 



arrangement of the le- 



i-J jfl" ~^~ verage connected with 

 ' ' ' ' the form of the move- 



able pan, and applica- 

 tion of the weight, 

 whicli admits, under 

 ordinary circumstan- 

 ces, of a constant flow 

 of water through the 

 grating into the pan 

 of the trap and over 

 the edge of the same 

 into the sewer or drain, 

 the lower part of the 

 trap being immersed 

 into the water, so as 

 to form a most effec- 

 tual water sealed joint, 

 of sufficient depth to 

 withstand the effects 

 of evaporation from 

 long drought, and should a stoppage be caused by a deposit of silt 

 or other matter, the water will rise in the body of the trap, until 

 it is about two-thirds full, at which point it raises the balance- 

 weight, and obtains considerable leverage by the peculiar formation 

 of the moveable pan, insuring a rapid discharge of a large body of 

 water, which by its force most effectually cleanses the trap, and 

 fluslies the sewer or drain, and instantly recovers its position, with 

 sufficient water to form the joint again, resuming its former action 

 till another stoppage occurs ; the form of the trap also insures on 

 the commencement of a thaw the ready ejection of any ice that 

 may liave formed therein. The annexed figure is a sectio nal view 

 of "a street grating and gully hole with the trap, which is re])re- 

 sented in its ordinary position, the water flowing from the grating 

 into the body of it. and over the edges of the moveable part into 

 the sewer or drain. The lower part of tlie body of tlie trap is 

 immersed in the water which is retained in the moveable part b)' 

 the counterbalance weight, thereby forming a perfectly sealed joint 

 and effectually preventing any smell from rising. 



Another advantage attending this trap is that it can easily be 

 fixed to any gull^' hole, and the price is very moderate, being about 

 £l each. 



GAS IMPROVEMENTS. 



(With Engravings^ Plate ll.J 



George Holworthy Palmer, of AVestbourne-villas, Harrow- 

 road, Middlesex, civil engineer, for "rt» improved method or mode of 

 producing inflammable gnues of greater piiritg and higher illuminating 

 power, ,.\c."— Granted April 17; Enrolled October 17, 18+7. 



The first part of this invention relates to an improved mode of 

 setting and arranging the retorts in conjunction with additional 

 vessels called " regenerators," so as to insure their being heated 

 uniformly to tlie required temperature (as shown in figs. 1 to 6), by 

 which method not only an increase of volume, but also an increase 

 in the illuminating power of the gas is obtained. TJie heating sur- 

 face of the regenerators may be further increased by the introduc- 

 tion of metallic chippings, or by sheet iron partition's. 



By this arrangement, the gas passes direct from the retorts into 

 the regenerators, where it receives a second dose of caloric, and 

 then flows in the usual manner through the sealed pipes in the hy- 

 draulic main, and then into the mechanical precipitator, to be next 

 e.xplained. The patentee recommends the retorts to be kept at a 

 bright cherry-red heat, and the regenerators at a dull-red heat, 

 visible by dayliglit. 



The second improvement relates to an apparatus called a '• me- 

 chanical precipitator," combined with a refrigerator (as shown in 



figs. 7 and 8), for the purpose of abstracting the vapours of tar and 

 naphtha, as well as the gaseous ammonia and its compounds. 



The third impro\ement relates to apparatus called " ammoniacal 

 filtering towers," through which the gas passes from the precipita- 

 tor, being washed in its course by liquid ammonia, descending like 

 rain through one or more ])erforated plates, as shown in Nos^ 1, 2, 

 and 3, in figs. 9, 10, and 11. By this process a further portion of 

 ammonia, contained in the gas, is absorbed without subjecting the 

 gas to an increased pressure, and the liquid ammonia is increased 

 in strength. 



The fourth improvement relates to an apparatus consisting of a 

 series of steam cliambers and condensers, Nos. 4, 5, and 6 as shown 

 in figs. 9 and 10, through which the gas passes from the filtering 

 tower ; each of these chambers is to be charged with a ^•olume of 

 ijure steam equal to the volume of gas. The crude gas with a vo- 

 lume of steam, passes first into No. 1 steam chamber,^ and then into 

 its condensing chamber, where the steam will be condensed into 

 water, which in its descent will carry with it a great portion of the 

 remaining gaseous ammonia and its various compounds ; after 

 which, tlie permanent gases flow from No. 1 condenser into No. 2 

 steam chamber, when the gas will be again saturated with steam 

 and will again flow into its proper refrigerator, to deposit tlie steam 

 charged with another portion of tlie product in a liquid form. The 

 gas will then pass into No. 3 cliamber as before, and thence into 

 No. 3 condenser, where is deposited the remaining ammonia and its 

 compounds, together with a portion of sulphuretted hydrogen. AH 

 these liquid products are to be made to flow, as fast as they are 

 deposited in the condenser, into a suitable receiver, sealed by an 

 hydraulic joint to prevent the gaseous vapours and gas from return- 

 ing into tlie condenser. From this last apparatus the gas will pass, 

 freed from impurities, into the " lime machines" or purifiers, 

 charged with dry lime, where it is divested of the remaining dele- 

 terious gases — viz., sulphuretted hydrogen and carbonic acid, and 

 proceeds thence to the gas holder, and lastly to the mains. 



The gas now purified goes into tlie gas-holder, and, in its transit 

 to the mains, may be naphthalised if required ; for this purpose, 

 apparatus may be employed similar to that described as the " am- 

 moniacal filtering towers." 



The fifth improvement is for avoiding the inconveniences which 

 arise on opening tlie purifiers and removing the refuse lime from 

 the sieves preparatory to recharging them with lime, and which is 

 to be effected by causing atmospheric air, heated or otherwise, to 

 be blown through the material employed for purifying the gas, and 

 discharged througli tlie furnace-bars or chimney-shaft, by means of 

 a " centrifugal bellows" or other suitable pneumatic apparatus, the 

 blast-pipe being connected to the exit pipe of the purifier ; thus 

 blowing out the contaminated air, &c., through the pipe by which 

 the gas enters the purifying ^■essel, an extra pipe and valve beings 

 attached to the entrance and exit pipes for this purpose. 



Reference to the Engravings. 



Figs. 1 to 6 show the mode of setting and heating the retorts and 

 regenerators: fig. 1, a sectional elevatiiui, and fig. 9, a front ele\ation 

 —each figure shows one-half of a set of retorts ; fig. 3, a longitudinal 

 section ; fig. 4, a plan of one of the retorts, showing the opening 

 through which the flame rises; fig. 5, sectional plan of the top re- 

 tort ; and fig. 6, sectional plan of the regenerators. — Similar letters 

 refer to similar parts : — a, b, c, retorts ; d, e, f regenerators, show- 

 ing the plates k to increase the heating medium, o^•er which the gas 

 flows from the retorts ; g,g, the furnaces ; A, /, flues through which 

 the flame rises from the furnaces, and, as indicated by the arrows 

 between and over tlie retorts and regenerators, to the shaft, and /, 

 the blow-holes. Tliere is one regenerator to each retort, of the 

 capacity of about two-thirds the latter. 



Fig. 7 is a vertical section of the " mechanical precipitator," and 

 fig. 8, plan of the same ; «, «, jierforated revolving fans, to agitate 

 the gas in the chamlier b, b, — the shaft is stepped into the lower 

 chamber and passed through an inclined plane, rf, rf, under wliich 

 the gas blows through the tar passing from the pipea^ ; and adjoiu- 

 ing is a chamber, p, containing a convoluted worm, or refrigerat- 

 ing pipe, g, to cool the gas after escaping from the chamber b, 

 through the cur\ed pipe, /I To prevent the gas blowing through 

 the aperture in the inclined plane where the shaft passes, the shaft 

 is inserted in a pipe sr, bolted to the inclined plane, being of an 

 altitude sufficient to overcome the pressure of the gas ; and instead 

 of the usual stuffing-box for the sliaft, an hydraulic seal t, is used. 



The pipe is kept cool by a supply of water passing througli tlie 

 chamber p, by the pipe //, entering' at the top and disci'argiug by 

 the pipe/. The pipes h and,/, together with tlie chamber e, form a 

 sj'phon ; the legs or pipes, li and ;', are furnished «it)i cocks ;j, to 

 admit or cut oft' the supply of water. An air-pump is used to re- 

 move the small quantity of air that may be in the syphon ; it is 



