455. Now, although the air expired, in consequence of its recomposition, may have undergone changes in bulk, yet it seems agreeable to all analogy to suppose that its weight will remain the same as the weight inhaled. This, however, is not asserted as a truth, but only assumed, in order to show the result of such a theory.

456. Then the air expired in twenty-four hours will be as follows:—

Bulk in cubic inches.Weight in grains troy.
Given out undecomposed as before665,646205,758.833
Recomposed carbonic acid gas38,26818,130.147
Azote liberated165,92750,027.405
Vapour of water as before2,219428.726
—————————
Total872,060274,345.111

weighing as before, but less in bulk by 446¼ pints: so that for every 100,000 inches expired there were inspired 101,774 cubic inches.

457. When from the weight of carbonic acid gas thus expired, viz.,18,130.147
we deduct the small portion inhaled in solution with the air105.130
—————
The remainder is18,025.017
The constituent parts of which are, oxygen derived from the air13,109.104
—————
And pure carbon derived from the blood being the difference4,915.913

Thus in the compass of twenty-four hours the blood has produced 10 ounces and 116 grains very nearly of pure carbon.

458. Now, from the oxygen consumed in twenty-four hours as aboveGrains.
15,757.913
Deduct the weight restored in the form of carbonic acid gas13,109.104
—————
The remainder must have been absorbed into the blood2,648.809
But the weight of carbon given out being as above4,915.913
—————
There is still an excess given outweighing2,267.104

459. Some azote, however, is absorbed into the blood ([439]) as well as the above ascertained quantity of oxygen.

The weight of azote so absorbed must be precisely2,267.104
if the theory be true, that equal weightsare expired and inspired. In which case, as the weight of theazote of the air inspired was, as shown above
52,294.509
While the azote expired could only have weighed50,027.405
—————
The difference would have been absorbed2,267.104

And thus the weight of carbon discharged by the blood is precisely compensated by the united weight of the oxygen and azote which it has absorbed.