78 THE LUNG PLAGUE OF CATTLE. 



careful observers have noticed the essential connection of lack of venti- 

 lation and pulmonary consumption. Baudelacque, Carmichael, Arnott 7 

 Lepelletier, Allison, Sir James Clark, Toy ubee, Guy, Greenhow, Sir Alex- 

 ander Armstrong, Parkes, and Aitken have especially insisted upon con- 

 sumption being a sequence of lack of ventilation. Dr. Cormac indeed 

 insists with great force that consumption is originated by rebreathed 

 air. 



The notorious prevalence of consumption in sailors has been directly 

 traced to the impure air in which they sleep, and an extensive outbreak 

 of lung disease (not tubercular) leading to destruction of lung tissue in the 

 English Mediteranean squadron in 1860 was clearly traced by Dr. Bry- 

 son to the contamination of the air. In a nursery hospital at Dublin 

 with entire neglect of ventilation 2,944 children died in four years, 

 whereas after the ventilation had been improved only 279 died in the 

 same length of time. 



Parkes (Practical Hygiene) says : 



But not only phthisis may reasonably be considered to have one of its modes of ori- 

 gin in the breathing of an atmosphere contaminated by respiration, but other lung 

 diseases, bronchitis and pneumonia, appear also to be more common in such circum- 

 stances. Both among seamen and civilians working in confined, close rooms, who 

 are otherwise so differently circumstanced, we find an excess of the acute lung affec- 

 tions. 



In this connection, the statement of the air breathed by an ox per 

 hour and that supplied him on board a ship with insufficient ventilation 

 or none may be instructive. The ox takes in with each breath about 5 

 liters of air. This is at the rate of 50 liters per minute, or 3,000 per 

 hour = 105.9 cubic feet. This amount of air is therefore rendered all 

 but irrespirable by each animal in the course of an hour. And this, be 

 it noted, is by breathing alone, and makes no account of the contamina- 

 tion by perspiration in the overheated hold, and by the emanations from 

 the accumulating excrement. 



On board the steamers we have found the space allotted to each bul- 

 lock to vary from 150 to 240 cubic feet. On the steamship " Holland," 

 loaded at New York August 21, 1881, we found the stalls amidships al- 

 lowed the full space of 240 cubic feet per head. In the bow, where there 

 was less height between the decks, the space was considerably less. On 

 the loAver deck, where 129 cattle were accommodated, the space allowed 

 each was 217.4 cubic feet. The port-holes in the upper deck were nine 

 inches in diameter, and there was one for each pair of stalls central and 

 lateral or for eight oxen. These, being well above the water line, would 

 be available for ventilation in ordinary weather. The port-holes in the 

 lower deck, similarly arranged, were about two feet above the water line, 

 and consequently not available for ventilation save in exceptionally 

 calm weather. The temperature on the main deck of this ship (between 

 the outer and main deck), when only half the cattle had been loaded, 

 was in the neighborhood of 90, although she was lying in the center 

 of the North Eiver with port-holes and hatches open, and a fresh breeze 

 blowing- from the north. 



On tne " Assyrian Monarch" the space per head was only 192 cubic 

 feet, but this ship was supplied with a ventilating fan or blower capa- 

 ble of delivering over 50,000 cubic feet of fresh air per hour, so that 

 her ventilation was abundantly provided for. In some smaller ships we 

 found the space per head to exceed little, if at all, 150 cubic feet. In 

 these, accordingly, a single hour without any change of air would threaten 

 the life of every animal on board, and two hours would endanger those 

 for which even the larger space is provided. It is true that such 



