HOME HYGIENE. 



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fresh air by means of an inlet pipe extending 

 from the outside of the building to the grate. 

 This is usually best laid alongside of the joists 

 on which the floor rests; but, in case the joists 

 have a direction toward the fire, the necessary 

 notching would weaken them too much, and 

 Mr. Eassie has recommended that they be laid 

 in the ceiling and descend alongside of the 

 chimney to the grate. A valuable adjunct to 

 the grate is a piece of Russia iron, well fitted 

 to the upper portion, which may be in hori- 

 zontal sections, to be fastened upon hinges, or 

 so placed as to be entirely removed. This pre- 

 vents the access of smoke to the room during 

 the ignition of the fire, and also increases the 

 vitality of the flame. 



5. Furnaces. The ordinary furnace is too 

 well known to require a particular description. 

 It consists of a cast-iron pot with a smoke- flue, 

 and a series of air-pipes above the level of the 

 fire-pot, the whole being surrounded with Rus- 

 sia or galvanized iron. The air-pipes are con- 

 tinuously supplied with fresh air by means of a 

 shaft or air-box extending from the outside of 

 the building. 



As the lower portion of these furnaces is 

 usually left open, whenever the ashes are raked 

 from the fire, the fine ash-powder is sucked in 

 the pipes and flues and is thence distributed 

 through the house by means of the registers. 



Alongside the hot-air pipes are usually 

 placed cast-iron receptacles for water. These 

 are int3nded to supply to the air passing out 

 of the registers the moisture of which it has 

 been deprived by the process of heating ; this 

 is usually imperfectly accomplished. Further- 

 more, the air-pipes become warped and affect- 

 ed by the heat, so that after a few weeks' or 

 months' use the coal-gas, and frequently smoke, 

 gains access to them and is thus distributed 

 through the house. Indeed, in many city 

 houses coal-gas is ever present in the rooms 

 from this cause. 



Parkes states that " the coal of ' average qual- 

 ity 'gives off in combustion: 1. Carbon. About 

 1 per cent, of the coal is given off as fine car- 

 bon and charred particles. 2. Carbonic acid. 

 In Manchester, Angus Smith calculated, some 

 years ago, that 15,000 tons of carbonic acid 

 were daily thrown out. 3. Carbonic oxide. 

 The amount depends upon the perfection of 

 combustion. 4. Sulphur, sulphurous and sul- 

 phuric acids. The amount of sulphur in coal 

 varies from one half to 6 or 7 per cent. In the 

 air of Manchester, Angus Smith found one 

 11111 of sulphuric acid in 2,106 cubic feet. 

 5. irbon bisulphide. 6. Ammonium sulphide 

 or ar* -ionium carbonate. 7. Sulphuretted hy- 

 drogen. 8. Water." 



These compounds are highly deleterious. 

 Not only do they exhaust the oxygen of the 

 air, by entering into new combinations, but 

 they exert a distinct toxic effect on the hu- 

 man system. It should be remembered in 

 this connection that the air-cells of the lungs 

 are, par excellence, the absorption surface of 



the body. Each air-cell being lined with a 

 delicate membrane in almost direct contact 

 with the blood, the conditions are highly fa- 

 vorable to the transudation of gases. The sur- 

 geon and dentist take advantage of this cir- 

 cumstance in producing the effect of insensi- 

 bility on their patients by the almost instanta- 

 neous absorption of vapor of chloroform or 

 ether, and, when directly absorbed, the fumes 

 of charcoal speedily produce death. That sick- 

 ness is not more frequently caused in furnace- 

 heated houses by the products of coal-combus- 

 tion, is due to the large dilution of the gaseous 

 substance in the atmosphere of the rooms. It 

 is obvious that great care is necessary not only 

 in the original construction of the furnace, 

 but in its management while in operation. 

 Furthermore, the water-basins in the furnace 

 need frequent replenishing, or the air of the 

 rooms becomes speedily deprived of its mois- 

 ture, and considerable suffering may be caused 

 the inmates. 



6. Stoves. Of the various patterns of stoves 

 no general or special description need be given, 

 except, perhaps, to mention that those are the 

 most objectionable which admit the air directly 

 to the fire-heated iron. It has been repeatedly 

 shown that red-hot iron allows the gases from 

 combustion of coal to pass through it readily. 

 Dr. Derby, of Boston, states that the injurious 

 effect of passing air over a cast-iron surface 

 heated with anthracite coal is due to carbonic 

 oxide, a highly poisonous gas. The nearer the 

 approach, therefore, to the open grate, as shown 

 in the Franklin or Galton (modified from the 

 Franklin) stove, the stronger the recommenda- 

 tion it can receive on hygienic grounds. The 

 self-feeding or "base-burning" stoves are high- 

 ly objectionable unless due care be taken to 

 keep the vertical tube filled with coal, thus 

 partially preventing the escape of gas. Its es- 

 cape can not, however, be entirely prevented 

 by this means. 



Warm water has been but little used as a 

 means of heating dwellings in this country, al- 

 though it has been proved to be of value in 

 various public buildings. The Barnes General 

 Hospital at the Soldiers' Home, Washington, 

 District of Columbia, is heated in this way. 



Steam-heat has also been little used for dwell- 

 ings, but it has lately been proposed to use 

 steam on a large scale to heat an entire village 

 or block of city houses, simultaneously sup- 

 plying the steam to separate householders in 

 such quantities as may be required. Although 

 steam and warm- water heating are free from 

 the objections of dust and coal-gas, they have 

 yet to be made practicable for small household- 

 ers. Furthermore, experience has shown the 

 writer that the wood- work in the vicinity of 

 heated steam-pipes shrinks badly, so much so 

 as to render this a highly objectionable method 

 of heating, unless some special measures be 

 taken to prevent it in the location of the pipes. 



Ventilation. As regards house-ventilation 

 in general, it is not too much to say that, in 



