[7]. See post.
[8]. Treatise on Road Formation and Cleansing.
[9]. See in the Appendix the form of calculation.
[10]. In Paris the greater proportion of the private houses are even now supplied with water only by water-carriers, and the means of the immediate conveyance of refuse, by a system of water-closets communicating through drains to sewers to receptacles for use, could not have been presented to the consideration of the men of science to whom the subject was referred. It appears that in the first class of houses in that city the cesspools were formerly only emptied once in four or five years, and that it is now considered a great improvement that they are emptied twice or thrice a-year. But the offensiveness and the frequent injurious effects from emptying and removing the contents, has led to the proposal of a plan of closed receptacles or removable tanks, in which the soil maybe carted away to the place of deposit for use as manure. The retention, however, of accumulations, which can only be constantly removed by means of water, and the want of proper supplies of water laid on in the houses very seriously disparages the salubrity and habits of the population of that city, as well as of the towns in this country where the same practice prevails.
[11]. Mr. John Martin, the artist, has endeavoured to direct public attention to the sewerage of the metropolis, and proposed the erection of a grand cloaca maxima, and various architectural works along the Thames, with the meritorious objects of preventing the pollution of the river, and saving the refuse. His plan was to form a canal on each bank parallel to the river, so as to intercept the whole of the sewerage, and convey it to large reservoirs or places of deposit at a distance. His plan for the north bank was a canal, constructed of iron, costing 60,000l. per mile, extending from Westminster to the mouth of the Regent’s Canal, “where the grand receptacle should be from which the soil should be conveyed to barges, and transmitted by canals to various parts of the country.”—Committee on Sewers’ Report, p. 169. The primary objection to this plan is that it would send the refuse still further out of the reach of large districts, where it is wanted as manure, to a place where it would only be available to the places for which canal conveyance would be convenient; that it would leave untouched the great obstacle to the use of manure, namely, the cost of removal and application by cartage and hand labour. The construction of the canal would also involve the disturbance of the whole of the wharf property; as originally proposed, it involved their entire reconstruction, and the erection of a grand colonnade along the banks of the river. For the removal of the refuse, engineers of practical experience agree that the most eligible plan was by various small conduits, not larger, where iron pipes might be necessary, than the pipes used by the water companies in bringing water into the metropolis, at a cost not a fifth, perhaps, of one large canal, and without any disturbance of property. For the application of the refuse as manure, practical experience at Edinburgh, and of irrigation elsewhere, shows that the most effectual mode of distribution for use is by water-meadows or drainage and irrigation combined; forming an unseen, unostentatious, self-acting system of excretory ducts, altogether superseding cartage or hand labour, and conveying the refuse in closed streams, acting constantly and rapidly until they distribute the refuse into the field of production.
[12]. A litre is one pint and a twentieth.
[13]. The spread of the knowledge of the fact that animals are subject to typhus consumption, and the chief of the train of disorders supposed to be peculiarly human, will, it may be expected, more powerfully direct attention to the common means of prevention. The following extract from a report on the labours of the Board of Health at Paris will show the effect of bad ventilation on cattle:—“The epizootie are in many respects less serious than the epidemics; nevertheless, as they often affect the animals which serve for the nutriment of man, and that apart from this consideration they may have grave consequences for the public health, they have constantly engaged the care of the council. In 1834, an epizootie was reported to the administration which prevailed among the cows of the communes round Paris, and which caused a great mortality. The researches of the council established that this epizootie was only a chronic disease, a true pulmonary phthisis, to which has been given the name of pommelière, and by which the greater part of the cows had been attacked which fill the stables of the milkmen of Paris and its environs. According to the council, the principal cause of the evil was to be attributed to the vicious regimen to which this species of animal is subjected. It is known that they pass a part of the year in stables perfectly closed, in which the space is not proportioned to the number of inmates, in which the vitiated air renews itself with extreme difficulty, and in which the heat is sometimes suffocating. It is known, also, that they pass suddenly from the food of the stable to pasture, and that in this change they go from the hot and humid atmosphere of the stable to a sudden exposure to the continual variations of the external air. This alternation of food and of heat and cold operates as a powerful cause of disease. But as the evil does not announce itself in a violent manner, as its progress is not very rapid, as there is even a period in the disease in which the animal is disposed to get flesh, the cow-feeder, who knows to what point to keep her, sells her when she is ready to calve. It is in a radius of 30 leagues from the capital that cows of this kind are purchased by the jobbers, who supply the milkmen of Paris. With these last they still hold out a certain number of years, if they are properly cared for, but in general they are kept in stables which are neither sufficiently large nor sufficiently airy, where they are exposed to the same causes which gave birth to the malady. The phthisis arrives insensibly at its last stage, and carries off every year from Paris and its neighbourhood a great number of these cows.” A similar discovery was only lately made as to the effect of defective ventilation on the cavalry horses in some of the government barracks in England; and it is stated, that a saving of several thousand pounds per annum was effected by an easy improvement of the ventilation of the barracks near the metropolis. An agriculturalist had a large number of sheep housed to feed them on mangel wurzel, but a great number of them sickened and died, and he declared that it was the food which had killed them. A veterinary surgeon, however, who happened to be aware of the consequences of defective ventilation, pointed out the remedy,—a better ventilation for the sheep, which were overcrowded. The defect was remedied; the sheep ate well, and throve upon the mangel wurzel.
[14]. Vide extracts from the official report in the Appendix.
[15]. The following were the terms of our instructions to the district medical commissioners of inquiry:—“A given amount of evil is experienced by a class placed under peculiar circumstances; a large portion of that evil is shared by other classes not under these peculiar circumstances; to attribute the whole of the evil experienced by the first class to those peculiar circumstances is obviously fallacious. It is conceived that it is only by investigating the subject with this precaution constantly in the mind that it is possible to arrive at a just conclusion. While you carefully observe the effects of labour on the children and the adult workpeople, and report every case in which you conceive it to be excessive, and state the reasons on which you ground that opinion, you are requested to investigate minutely the concurrent causes of ill health. With this view you are requested in every case to examine and report the state of the drains in and about the factory: the state of the neighbourhood of the factory as to dryness or dampness, cleanliness or filthiness: the state of the houses and neighbourhood in which the children and adult workpeople take their meals and exercise (if they leave the factory), and where they sleep: the state of the air within the factory, and which the workpeople usually respire, whether it be fresh or whether it be not fresh, owing to deficient ventilation,—whether it be pure, or whether it be rendered impure by effluvia floating in it, and if so, what the effluvia are: what organs of the body are likely to be injured, and what, from careful examination, you find to be actually injured: the temperature of the air, the highest, the lowest, and the average temperature, and the condition of the air as to dryness or moisture.”
[16]. Rapport de la Commission des Epidémies de l’Académie Royale de Médecine pour l’année 1839 et un partie d’ 1840. Par M. Brichetan, Secrétaire Rapporteur de la Commission.