J.OJ. 30, 1S35.] 



♦ KNOWLEDGE ♦ 



85 



but these are corresponding elements of the areas A P K S 

 and A P K A- B ; for such areas as Hi n i may be neglected 

 compared with m n Q P. Hence 



Area A P K S = ^ area A P K A B = ^ trap B S K k. 

 This is a convenient relation. We may present it in 

 another form. Fur, joining B K, and drawing normal 

 K N (whence M N = 2"A S)— 



trap. B S K A = .\ M K (K A -f- B S)= l M K (M B + M N) 

 = 1 MK . BN=aBKN 

 Area A P K 8 = ^ A B K N 

 Producing K S to meet the parabola in K' and drawing 

 IC k' perp to A B A-', we have 



Area K P A K =i trap K A- A' K'. 



{To he continued). 



CHAPTERS OX MODERN DOMESTIC 

 ECONOMY. 



Xiri.— THE FKAMEWORK OF THE DWELLIXGHOUSE. 

 GENERAL PRINCIPLES OF COXSTRVCTION — {continued). 



(v.) XT^VERY house ought to be furnished with an 



E' 



inspection-chamber, so -situated that it cannot by 

 any possibility be a source of nuLsance. The chamber should 

 be so arranged as to admit of ready acces-s, and into it 

 .should flow the separate sy-'tems of wasts drainage from the 

 entire household, pre\ ious to their common exit therefrom 

 by means of the principal house-drain. A well-regulated 

 inspection chamber, then, would embody pi-ovision for the 

 influx from (1) the soil-pipe, (2) the back-yard drainage, 

 (3) the waste water from scullery and housemaid's sinks and 

 wash-basins, where those conveniences obtain. To be theo- 

 retically as well as practically perfect, each of the systems 

 should be most rigorously isolated ; so that the domestic 

 drainage may be compared to a valvate arrangement of 

 tubes, each one separate from the others, each one destined 

 to fulfil its own peculiar functions, and all of them to unite, 

 after being duly trapped and ventilated, in the inspection- 

 chamber. The very name of the latter savours, as it ought 

 ro do, pre-eminently of health, for it suggests that grand 

 principle of sanitary reform which seeks to facilitate 

 careful supervision, and afibrds scope for observation and 

 experiment, thus enabling us to gain knowledge, the 

 acquisition of which is now, as in the days of the ancient 

 sage, power. 



The inspection chamber may thus be viewed as the distal 

 termination of the principal house drain, and through it 

 all the excrementitious as well as harmless products are 

 made to pass into the latter, with but one exception, and 

 that is, although not all-important, yet very necessary to 

 the intelligent display of the domestic drainage system, 

 viz., the provision for the removal of front-area water. 

 An open-trapped gully, with a suitable syphon pipe and 

 grease-dLsposing apparatus, should receive such innocuous 

 ivaste and rain-water, and convey it to what may be called 

 the proximal end of the house-drain. At this part another 

 iaspection-chamber must be added, and is technically 

 termed the '■ man-hole." Tlie man-hole should give free 

 access to the house-drain as well as to the affluent pipe 

 'rom the front-area gully : thus both the proximal 

 ind distal chambers of the house-drain afford their care- 

 ful scrutiny when desired, and as that duct ought 

 to be laid in a straight line between the two, it can 

 be readily examined, and, if necessary, cleaned with the 

 utmost ease throughout its entire course. The man-hole 

 further furnishes easy access to the essential " disconnec- 

 ting-trap" between the house-drain and the public sewer; 



and, to proviiK' against possible accidents, the trap must be 

 furnished with a clearing branch, down which a rod can be 

 made to pass, in the event of an obstruction, which but 

 rarely occurs, between the house-drain and the street sewer. 

 The manhole, also, ought to be well ventilated by an inlet 

 for frfshair, the rnisoii (^'/jr of which is to induce a current 

 through the domestic drain, and upwards along its main 

 continuation (the soil-pipe), well over the chimney-stack by 

 its ventilating head into the open air. 



We cannot dwell too strongly upon the urgent necessity 

 for the observance, to the letter, of the foregoing prin- 

 ciples, since they seem to be everywhere violated, not only 

 by the builder, who is devoid of any i^ood training, but by 

 otherwise well-educated but negligent persons, wliosc chief 

 object is founded upon that pernicious commercial i)rin- 

 ciple of erecting cheap buildings which shall allbrd a ([uick 

 return, irrespective of whether they are sanitary abodes or 

 the reverse. It is to these two sins of ignorance and 

 avarice that the evils of the essentially-defective hydraulic 

 system are mainly attributable. The escape of sewer-gas, 

 whether it arises from bad workmanship or inferior ma- 

 terial, is usually dealt with by the " patcli " system ; cases 

 without numb;r might be quoted in corroboration here, but 

 at present they would be foreign to our purpose ; we hope, 

 however, to adduce evidences when we come to treat of 

 structural examples, and pro tempore may direct our 

 readers to that admirable institution, the Parkes Museum 

 of Hygiene, where the wreckages, with their histories, 

 stand as monumental warnings to the would-be sanitarian, 

 and declare more eloquently than any mere words can do 

 how important it is that we should be even hypercritical in 

 these respects when exercising our choice of an abode. 



We had intended, at the outset of these chapters, to 

 leave the consideration of closet-furniture, as such, to a 

 future occasion ; but, on second thoughts, we deem it advi- 

 sable to introduce tliat subject here in its right order of 

 sequence as part of the fixtures in the framework of the 

 dwelling-house. So, also, do the items connected with the 

 house-drainage system, such as sinks, baths, io., call for 

 comment in this place. 



With regard to the closet-trap, it is important that it 

 should form part of the tubular system ; that is, in the 

 case of an upstairs closet, the trap ought to be part of the 

 soil-pipe ; and the joint, which is the weakest place, should 

 lie between the closet-fixings and the soil-pipe, so that, in 

 the event of an accident, the latter may yet be securely 

 trapped and incapable of transmitting foul gas into the 

 rooms of the house. In like manner, the basement closet- 

 trap, for a similar reason, should form a jiart of the drain 

 and not of the closet furniture. In all instances, the trap 

 should afford absolute security from sewer-gas, and the 

 ventilating arrangements should in every case find exit 

 into the open air, away from windows, and where the 

 escaping foul air cannot possibly cause any injury. The 

 varieties of closets and their accessories now in the market 

 are manifold ; we shall hereafter give accurate descriptions 

 of the best of those in general use, or about to be intro- 

 duced, and point out carefully the faults of defective 

 types of structure. 



The waste-waters of the intra-household fittings are : — 

 bedroom slops, scullery, pantry, and housemaid's slops, and 

 dirty bath-water. Bedroom slops are usually emptied into 

 the closet-basin, which should, therefore, in supjjort of 

 cleanliness, be provided with hinged lids. Sink and bath- 

 water should be conducted to a receiving head, or a 

 gully carefully trapped, and from thence through the in- 

 spection-chamber to the drain ; in no case ought they to 

 be connected with the soil-pipes, or with any part of the 

 excrementitious conduits directly. 



