898 



THE SOUTHERN PLANTER. 



[July 



From the Scientific Artisan. 



House Warming and Ventilation. 



Those who have made experiments for 

 the purpose of deterniining the quantity of 

 pure air required per minute by each indi- 

 vidual, vary in their conchisions. They 

 publish from 3 to 10 cubic feet, but when 

 physiological facts in relation to size of 

 lungs, health of persons, and various cir- 

 cumstances are considered, we conceed the 

 accuracy of either amount. 



We learn by science that the laws of 

 nature do not long permit the enjoyment of 

 health where pure air is not; and also 

 when health is lost there can be no^^ossible 

 recovery of it without the aid of pure air. 

 When we breathe, although the air in the 

 lungs is on one side of a membrane and the 

 blood on the other, a reciprocal action takes 

 place between them. The blood receives 

 through the membrane oxygen from the air, 

 and at the same time the air receives from 

 the blood carbonic acid gas and watery 

 vapor. The amount of oxygen and car- 

 bonic acid gas thus exchanged are said to 

 be equal — that is, pure air taken into the 

 lungs is expelled with about 85 per cent, 

 carbonic acid gas and an equal amount of 

 oxygen has been taken from it by the blood. 



It appears that a middle sized man, aged 

 about 38 years, and whose pulse is 70 on an 

 average, gives off 302 cubic inches of car- 

 bonic acid gas from his lungs in 11 minutes, 

 and supposing the production uniform for 

 24 hours, the total quantity in that period 

 ■would be 39,534 cubic inches, (agreeing al- 

 most exactly with Dr. Thompson's estimate), 

 weighing 18,683 grains, the carbonic acid in 

 which is 5,363 grains, or rather more than 

 11 ounces Troy. The oxygen consumed in 

 the same time will be equal in volume to 

 the carbonic acid gas. See respiration under 

 Physiology in the Encyclopaedia Brittanica. 



It has been shown by experiment that 

 pure air once breathed contains 85 per cent, 

 of carbonic acid, and that the same aiT by 

 continued respirations would not take more 

 than 10 per cent. Hence the necessity in 

 the preservation of health of breathing air 

 but once as it enters and departs from a 

 room. Proper ventilation permits the air 

 to pass away after having been once breathed, 

 for in respiration the air expelled from the 

 lungs being warmed ascends and is not 

 where it may be received by their next ex- 

 pansion. But if by insujEcient ventilation 



air is breathed more than once^ it gives less 

 oxygen to the blood and takes less carbonic 

 acid and watery vapor trom it than is neces- 

 sary for the preservation of health. The 

 efficacious action of the blood ceases be- 

 cause of the deleterious presence of car- 

 bonic acid in the blood and in the air. Car- 

 bonic acid gas has a little more specific 

 gravity than atmospheric air, but the dif- 

 ference is so slight that when in a current 

 of air it is carried upward, or where there 

 is no current it tends downward. When a 

 multitude meet in a room which has not 

 been planned to admit fresh air, the car- 

 bonic acid gas descends to the floor and 

 from thence it accumulates upward. When 

 it enters the nostrils of the assembly the 

 faces of all become pale, most of them think 

 impatiently of the pleasure of breathing 

 out-door air, and some, perhaps, faint. I 

 am persuaded that the germs of painful sick- 

 ness and early death are thus often fixed in 

 the human system. 



We reflect with astonishment upon the 

 sad consequences of bad ventilation — the 

 great loss of cheerfulness and success in 

 the [^.ttainments of intellectual power. A 

 healthy circulation of air is often disap- 

 proved by the untutored. As needful 

 medicine which is unpleasant to the taker 

 may be rejected, so a healthy circulation of 

 air by a morbid sensibility may be prevented. 

 Because of bad ventilation children in 

 school may dread their task. For want of 

 pure air perhaps their digestion is impeded. 

 They then feel as if a heavy burden was 

 upon them. If they try to learn they sel- 

 dom succeed. If they succeed in commit- 

 ting a paragraph to memory it is soon for- 

 gotten. Being ignorant of themselves and 

 the causes of their maladies, they judge 

 themselves incapacitated for intellectual pur- 

 suits. 



It is from the same cause, very frequently, 

 that religious congregations have many mem- 

 bers who spend in church an hour of sleepy 

 thoughtlessness, and return home without 

 being able to tell the points of the speaker's 

 discourse, though they had been where one 

 of the most instructive and interesting ser- 

 mons was preached. It is doubtless be- 

 cause of bad ventilation that the power of 

 the advocate of the gospel in the pulpit is 

 much less than it otherwise would be. 

 Houses of worship are mostly so constructed 

 that the impure air is driven^ by opening 

 the door, upon the preacher. He, in the 



