Page:Popular Science Monthly Volume 19.djvu/676

658 trary of human continuity. The cemetery ought, therefore, in every city to be preserved and improved, as something indispensable to the intellectual and moral improvement of the people. It constitutes an interest of the first order, the care of which justifies all necessary efforts and expenditures. With a large part of the public, however, hygienic considerations far outweigh all the moral and social advantages to be derived from the maintenance of cemeteries; and, in justice to the views of this class, it is proper to inquire to what extent the existence of cemeteries, in or near a city like Paris, can be dangerous to the public health.

The injurious effects attributable to cemeteries can be exhibited only through the air, the soil, and the waters. Let us examine each of the three cases.

The air may be contaminated by the disengagement of poisonous gases, or by the propagation of miasms.

The decomposition of bodies in the earth is a real organic combination; its products are quite well known. The principal and most abundant of them is carbonic acid, a substance that is generated by the slow combustion of the carbon contained in all organic matter, vegetable or animal, whether it be a blade of grass, a leaf, wood, manure, or a dead body. It may be disengaged from the soil in cemeteries, and most hygienists have till now considered it one of the principal causes of their insalubrity. This is a mistake. We have on a recent special occasion made an approximate calculation of the maximum quantity of carbonic acid that can be produced in the cemeteries of Paris. The results of these calculations, which are based upon numerous weighings of corpses made in several hospitals and on the most authentic data of the chemical composition of the human body, show that this quantity is infinitely less considerable than has been supposed. The total weight of the bodies consigned each year to the cemeteries in Paris is 1,389,000 kilogrammes (3,472,500 pounds). If all their carbon were transformed (which is not the case) and disengaged as carbonic-acid gas, they would furnish 1,257,000 kilogrammes (3,142,500 pounds) of that gas in five years. Now, according to the calculations of M. Boussingault, we may estimate the quantity of carbonic acid produced in Paris, by the respiration of men and animals and the different processes of combustion, at 18,000,000 kilogrammes (or 45,000,000 pounds) in twenty-four hours. The combustion of illuminating gas alone in Paris (218,813,875 cubic metres) produced last year a quantity of carbonic acid thirty-five hundred times more considerable than all the dead buried in the cemeteries during five years could give at the maximum rate of exhalation. The Grand Opera-House alone gives out every year thirteen times more carbonic acid from its gaslights than could be disengaged from all the cemeteries put together, even if all their carbon were converted into gas.

After examining these figures, and comparing them with the very