CHAPTER II. THE HYGIENE OF HABITATIONS. (Part 3)

from the WATKli ,sr/77,)' 17 siirfaoo, and can l)c rcadird l»y diu'iriii.ir <1<'<'I) ciioii;,'!! into tlu> f^round. l)iirin<i the ])rn(c>s (tf pcrcohitinii into tlic .uroiiml the water is filtcri-d and loses some ot" its inipnritics, hnt in ])assini; tin-on,i,^li tiie \arions soils it nia' take nj) certain minerals with which it conies in contact and the>e iu'come snspended or dissoKcd in it. Tlio nnderj,'round water basins lie sometimes at a very ^reat d(^])th. The water tlH'n'in is in constant motion in a xcrtical or horizontal direction, and as the ])ressnr(> is sometimes jjreat tlie water may crop ont at some snrface in the form of si)rinf!;s. Tlie water in such sjjrincs, when at a proi)er t(>m])era- tnre and free from minerals, is i)alatable and whole- some. Sometimes these springs have considerable mineral ingredients dissolved, and are at high tem- perature, owing to the character of the earth's crust which the water traverses. These arc the sources of "hot" or "mineral" springs. The deej)-lying underground water may be reached by driving wells into the ground into the lower imper- meable stratum. \Vater from deep wells of this kind is very good. The water from shallow wells or those dug into the first near-sm'facc-l> ing under- ground water basin is ajjt to be impure, because such wells usually ta|) a subsoil water, which is gained by surface drainage from localities largely contaminated with organic matter, manure, and sewage. The pri\ ies and cesspools near liaititations almost always drain their lifjuid contents into the sources from which shallow wells get their water, and many epidemics of typhoid and other diseases have been 48 HYGIENE OF HABITATIONS traced to the use of polluted shallow well water. Shallow wells are also called dug wells to distinguish them from deep and artesian wells, which are com- monly bored or driven. Wells must be dug at con- siderable distances from houses and stables, and at places where no surface impurities can drain into them. They should be lined with brick and cement, or with glazed tiles set in cement, and also fitted with proper covers to prevent the falling in of filth from the outside. The water is drawn from the well in buckets or pails either worked by hand, windlass, or by means of suction pumps or other mechanical devices. Aqueducts. — For the supply of large towns with their millions of population immense water-supply works are needed. Their construction and the supervision of the water area must be in charge of engineers. House-water Supply. — Where there is a town-water supply system, houses are supplied from the street mains; the size of the street mains depends upon the water-pressure and the number of houses to be sup- plied. The branch house-water supply pipes coming from the street mains should not be less than three- quarters inch for small houses and from one and a half to two inches for larger houses. The house pipes are connected with the street pipe by " corporation taps." There should be a stop-cock under the side- walk, and also one on the service pipe at the entrance to the cellar. Street mains are made of galvanized iron; some of the house pipes may be made of lead. The materials and workmanship of all water pipes must be of the best, and they shoukl be protected from freezing whenever exposed. ]vati-:r srri'LY 49 Wlu'iu'vcr the ])rcssiir(' of the street inaiiis is iiisiidi- eieiit to lift the water to the heij^lit of the U|)|)er stories of a house. >torai:e tanks or cisterns must he |)ro\i(l(M| upon tlie roof. 'I'hese tanks are eoininonly niaile of ee<hjr or cypress wood, are rouml in shajx-, and >houlil rest upon a sohd foun(hition. ])retVral)Iy upon iron l)eauis. \ hen locatcil within the house the tanks are metal lined. All tanks should i)e i)ro\ided with suit- able covers, also with overflow ])ipes and water-wa.ste protecting valves. The overflow max he discharged onto the roof, or lead down into the cellar and dis- charged into a sewer-comiected. |)roperly trapped water-snpj)lied open sink. In order to lift the water to the highest .story some mechanical means, sucii as jjumps, driven by gas, steam, or electricity, may be necessary. Hot-water Supply. — Modern houses are not only provided with hot water, but provisions are also made to suj)ply the house with hot water necessar.- for l)athing. washing, and cleaning ])urposes. The hot-water supply is derived in most houses from boilers of copj)cr or iron, connected with the kitchen range. In larger houses special hot-water furnaces and boilers may be provided, from which the hot- water pipes go to every fixture in the house. The heating of water by means of electricity is practicable wherever there is electric power within the house. A simple device to heat water in a vessel is by means of an electrically heated metal coil placed in the ves.sel. Purification of Water. The large amount of impuri- ties, some of them Ncrv dangerous to the health and life of the consuiner>, wliich are coninionh found in 4 50 HYGIENE OF HABITATIONS drinking water render the problem of water purifica- tion an important one from a sanitary stand-point. Water purification should be twofold, public and pri- vate. Whenever the water supply is collective, public, and on a large scale, the community at large should provide for proper water purification. Whether there is a public water-purification plant or not, every individual household should provide some means of local water purification. Methods of Domestic Water Purification. — Water may be purified for domestic use by sedimen- tation, boiling, distillation, chemical means, and by filtration. Sedimentation. — Water may be freed from its coarser particles of impurities of sand and dirt by letting it stand in a vessel from twelve to twenty-four hours. This may also free the water from such organic matter and impurities as are held in suspension, without, however, clearing it of the impurities held in solution. Boiling. — All living organic matter and germs are destroyed by raising the temperature of water to the boiling-point and by keeping it at that temperatue for a certain time. This is the cheapest and most available method of purification, and is also the most efficient. The objection against boiled water is the insipid taste which results from the expulsion of air and carbon dioxide by the process of boiling. The pleasant taste of the water may be restored to boiled water by aeration, or by charging it with carbonic acid gas. Distillation. — This is the surest and best means of removing all impurities. It kills all germs, including ir.tv/'./i' SI ri'iA' 51 iill <tt" tlu' spores, and <:ivi's an ahsolutrly i)iir(> water which when aerated or char.m'd with carhoii (Mo\i(h- is -ery pahitalih' in aihhtion to Ix'ini: pnre. The ohjec- tion to distilhition of water for (h»niestie purposes lies in the necessity f(»r a proper apparatus; hut the time seems to l)e ap|)roaciiin<; wlien every house will l)c furnished with watcr-(li>tillin;r apparatus just as it is at present furnished with a cookinj: range and hot- water hoiler. The apparatus to l)e of value >houl(l he sinii)le in construction, easily o])erate(l. (lui'al)le, strong, and readily eleansihle. It should furnish an adequate supi)ly of water for all domestic purposes with little tronhle and at small ct)>t. Such an ideal ai)paratus has not as yet heen invented, l»ut there are a number of de\ices which api)roach it and may safely be used. Chemical Mrnns. — The settling of turhid water may be ha>tene(l by th<' addition of a few grains of alum (not more than six grains to the gallon). The addition of small fpiantities of ])otassium i)erniaii- ganate has a destructive effect ni)on organic matter. Addition of tea leaves and other vegetal)les con- taining tannin i> said to reduce the danger from organic imi)uritie>. l»ut this is i)roblematic. Other chemicals, like borax aiul i)oracic acid, cojjper sul- phate, etc., have been advocated. l)Ut when u>ed in too small (piantities they are of little or n«» value; when u>cd in largci' (piantities the' ma> become almost as dangerous to health a- the iinpuriticv which the- are intended to destroy. Watku Fii.tra I IoN. Water ma.- ix- j)uriticd by filtration. /. ( ., l)\ letting the water pass through 52 HYGIENE OF HABITATIONS some material which is capable of retaining some or all of the contained impurities. The value of a water filter depends upon the following factors: 1. The character of the filtering medium and its ability to retain and remove from the water as many impurities as possible. 2. The thoroughness of the process and its rapidity. 3. The ready cleansing of the filtering media and its ready disinfection. 4. The simplicity, cheapness, and accessibility of the filter. It is claimed for some filters that they are able to remove all the organic impurities from the water, as well as the bacteria, but this is not yet proved. It is certainly true only of a very few filters upon the market, and of those only when they are new. Whenever water is suspected of containing patho- genic bacteria, dependence upon filters may become dangerous to health, and distillation is the only sure way of securing purity of drinking water. The materials which are used for filtering water are sponges, wool, asbestos, sand, stone, porcelain, infusorial earth, spongy iron, magnetic carbide of iron, charcoal, etc. Sponges, wool materials, and asbestos cannot A'ery well be depended upon; at best they act but mechanically, easily get dirty, and are difficult to clean. Sand and porous stone will arrest suspended matter; they may even remove some of the organic matter. It is doubtful whether all organic impurities and microbes can be removed by them. Charcoal is a very good filtering medium in some respects. Animal and not wood charcoal is used. MM 77;/.' sri'i'LY i^y* AniiiKil charcoal is prcpanMl from calcined cnislicd animal hones, and ma> h»' n>cd in hlock form or in tlie form of a jiowdcr. < harcoal rcmo\c^ cnlnrinj; matter and considerahle or<:anic matter from water, hilt does not remove all organic impurities, ('harcoal used for filtering must he frecjuently recalcined. I n- glazed procelaiu is used for filtering purposes aiid is quite effective in remoring water impurities, ])ro- vided the filtering porcelain is frequentl>' cleansed, as the impurities are apt to hecome clogged. Infusorial earth is used in the Herkefeld filter. It is pressed in the form of hollow tuhes. The water passes under pressure through the fine pores of tlie filter and gains access to the tap. It is claimed for this filter that when new it will remove all organic matter and bacteria from the water. The filter is made in various forms and sizes and may be attached the the house-sink faucet. The filtering tube must be removed frequently, sometimes more than once a day, and the dirt accumulating upon the surfaces washed off", otherwise the filtering process becomes slower and slower and stops when the pores of the tubes become clogged. Ice. — The use of frozen water in the form of ice is very extensive, and when used for drinking ])urposes there is the same danger of organic imi)urities as in ordinary unfrozen water. As most of the ice used is oi)tained from the surface of lakes, ponds, and rivers subject to organic con- tamination, tlie use of ice may become very dangerous. It is best to use ice only as a cooling medium, with- out melting it for drinking i)urj)oses. Ice may be 54 HYGIENE OF HABITATIONS made from distilled or boiled water, and is then free from impurities. It has been shown experimentally that freezing does not kill the bacteria in the water. Ice-chests and refrigerators have become a household necessity. They are commonly made of wood, hard wood is best, with mineral packing in the double wall to insure non-conductivity. Within the refrig- erator is lined with metal or porcelain or enamelled iron. Some refrigators are kept cold by means of electricity without the use of ice. The waste pipes from the ice-box should never connect directly with the plumbing of the house, but should discharge into the sewer-connected, properly trapped, water-supplied, open sink. The waste pipe is sometimes provided with flap valve to prevent the entrance of warm cellar air. HOUSE DRAINAGE. Sewage and its Disposal. — One of the most important needs in connection with human habitations is the disposal of the organic matter and sewage due to the presence of the inhabitants. The average adult passes about 3 ounces of solid and about 40 ounces of liquid excreta, which when multiplied by the num- ber of house dwellers forms a large amount of organic detritus. This organic matter if left exposed for some time begins to decompose and undergo putre- factive changes, evolving foul gases and odors during the process. The solid excreta may also contain a large number of germs, some of which, such as the llorSK Dh'MSAtiE .v. ^cniis III' cholcrM. typhoid, intestinal disease, and others, are ]iath(>^enic. 'I'he ortranie excreta and detritus are einhraeed under the ^'eneral term of "sewa^M'." and luiless there i> |)r()i)er and eH'ective disj)()sal they l)e('()iiie not only disai:reeal)le and uii- |)leasant. hecause of the foul odors and t,Mses,l)nt, also, at time-, dauLTcrons to iiealth and life. Methods of Sewage Disposal. Tin- j^rincipal methods of ultimate disj)()sal of sewaj^e are the followinji: Cremation, chemical i)reeipitation, land irrigation, disposal into rivers, lakes, and seas, and the various modern bacterial, sejKic, and biological methods. The innnediate disposal of sewage from the houses may he dry or by means of water. In isolated houses without water suj)ply, and with a few house dwellers, the means of disposal of sewage is by pails, earth closets, privy vaults, and cesspools. When there is a water-supply system the sewage may be carried out through a system of plumbing pipes and fixtures, and be disposed of in cesspools or through land irrigation. Pail Sysfem. -The pail system is by means of the simple experlient of gathering the solid excreta into tight pails or receptacles and then removing the content- when the pails are full. Privy Vaults. Privy vaults are in extensive u>e in this coimtry, in rural communities, villages, farms, and in some cities which are not sewered. There are a large ninnber of them in the outlying boroughs of New York and the outskirts of other cities. The privy vault, as ordinaril.x con.strueted, is a hole in the ground. o-er which there i- ;i rai>e(| platform 56 HYGIENE OF HABITATIONS with a seat, the whole covered with some sort of a shed. The privy is always a nuisance, because of its proximity to the house, of the foul odors emanat- ing from it, the flies and insects it attracts, the contamination of surrounding soil, and the possible pollution of near-lying wells and water courses. This pollution of the water and of the soil is the greatest objection against privy vaults. These privies remain in the same place so many years that the soil beneath them becomes a veritable sewage lake from which contamination of the surrounding soil and of the water supply nearby results. The diseases which may be due to such soil pollution are typhoid fever, hookworm, dysentery, tapeworm, etc. In the South the terrible ra^'ages of the hookworm disease are due mainly to soil pollution and unsanitary privies. The principal i)arts of a privy are the shed, the seat, and the receptacle into which the excreta are dropped. The shed in a sanitary privy should be made of tightly fitted boards, with windows properly screened and doors well closed in order to prevent insects and flies from gaining access. The seat should be so arranged as to be convenient for use, and should be free from contamination of excreta. The receptacle or the place into which the excreta are dropped should be more than a mere hole in the ground, from which the liquids percloate into the surrounding soil, and in which the excreta remain and decompose; it should be made water-tight by being lined with cement or some non-absorbent material. The excreta when dropped into this water-tight receptacle will remain there and must be removed from time to time. A HOUSI-: i>h'M.(;F '), >till l)rttt>r iiu'tliod is to ])Iii(r in such \viitcr-ti;,'lit rcccptaclt's a ti<:lit |)t)rtal)lc pail whicli is luuif; on a hook from tiu- x-at. The cxtrcta arc (h-op])C(l directly into the pail, which may he renioNcd as soon as it fills, and the contents cremated or disintVcted. the pail cleansed, washed, an<l disinfected, and returned to its place. For the i)urpose or removing; these pails and cleaning the vault beneath the privy each part of the privy should be made with a slinj; cover so as to i)e accessible. Cesspools.- These may be used when the house is pro\i(lcd with fixtures and pipes to carry the sewage out. and to collect it in a cesspool at a point distant from tile house. The so-called "leeching" cesspools, which are not water-tight and allow liciuids to drain into the groimd, are oj)en to the same objections as privy vaults. AVhen cesspools are water-tight, they must be emptied at periodical intervals or provided with automatic ejectors and siphon apparatus to discharge their contents. The best nuxle of discharge is by means of a system of intermittent filtration, or subsoil irrigation. The sewage is emj)tied into earthenware pipes with open joints, which lies several feet under ground and radiate in different directions, through land tt> be irrigated. The liquid sewage drains into the ground at the joints and is efi'ectively disposed of, enriching the land. • Tlif Wdtrr-cdrrKKjf Mcthiid.'^ This method is now extensively used in cities and towns where sewers are built. It is the best means of disposing of the liquid and sewage contents of hou.ses and streets. The sewage from the sewers is either collected and 58 HYGIENE OF HABITATIONS led to the ultimate disposal works, or is carried into the sea and