Gradually, as decay progresses, the aerobic organisms increase in number.
Such organisms are called aerobic or air-living.
Decomposition must be rapid and aerobic, but not too aerobic.
First, the process must stay aerobic.
Here some air is present and aerobic bacteria (those which thrive where there is oxygen) develop and complete the process of transforming the wastes into clear water.
The germ content of butter is said to be greater on the outside of a package than within the mass, due doubtless to the free access of air, thus favoring the growth of the aerobic forms.
Sewerage in the first tank is worked over by aerobic bacteria, the kind that require a small amount of oxygen in order to live and carry on their work.
Daily aerobic exercise will strengthen the heart, gradually slowing the heart's resting pulse rate, indicating that the heart has become much stronger, pumping more blood with each pulse.
Heaps built with significant amounts of coarse, strong, irregular materials tend to retain large pore spaces, encourage airflow and remain aerobic.
Most exercise physiologists claim that the physical, and very likely also the psychological, effects of other aerobic forms of exercise, such as bicycling, swimming, and cross-country skiing, are essentially equivalent to running.
To the upper portions of the canal the air still has access, so that even in the stomach aerobic microbes may be found, but in the lower parts of the intestinal canal oxygen is absent, and only anaerobic microbes can be developed there.
If the inoculating microbe is aerobic, it can only be cultivated in blood by taking away the oxygen from the globules, which retain it with a certain force for their own life.
At the same time, though it is entitled to be called an aerobic organism, it differs essentially in certain respects from the parasite of splenic fever.
We can well imagine that in an animal, scarcely formed, the power of oxygenation of the blood globules is not as yet capable of preventing the aerobic microbe from turning to its own account the oxygen of the blood.
It appears certain, then, that every boil contains a microscopic aerobic microbe, and that to it are due the local inflammation and the consequent formation of pus.
At the present day bacilli are usually divided into two groups, those which grow in the presence of free oxygen (aerobic), and those which will not grow in the presence of oxygen (anaerobic).
These are best formed in concrete with smooth surface, with a semicircular level weir from which the liquid overflows into a semicircular collecting open carrier leading to the aerobic process on land or contact bed.
I seem to have observed as a general principle, that, provided the blood corpuscles are in good physiological condition it is difficult for aerobic parasites to develop in the blood.
This plant is interesting from the fact that the effluent from the anaerobic bed is distributed over the aerobic bed by means of a revolving sprinkler which prevents the liquid from passing unequally through the large grain, porous material.
Loam on sand and gravel the best medium for aerobic organisms to work in.
Bacterial infections of the bladder are not inconceivable, although luminous bacteria are strongly aerobic and would not thrive under anaerobic conditions.
Those which work in contact with air (aerobic) show a tendency to prevent coagulation and to form an alkaline yellow slime on the surface of the latex.
The scientific working of a septic tank depends upon the destructive work of two kinds of microscopic life known as aerobic and anaerobic forms of bacteria.
As the liquid is drawn off, air enters freely between all the layers, so that the deposited solids are then immediately brought into close contact with air, from which the aerobic bacteria and other organisms can draw the oxygen they need for their life functions.
By breaking up the complex organic substances in the manure into new and simpler forms, they advance the process of putrefaction through the initial stages; and when this is accomplished, they die and give place to the aerobic, which, as we have just seen, effect the final transformation of the organic matter into such simple substances as water and carbonic acid gas.
After an appropriate interval the liquid passes to filter-beds, where it trickles over and through beds of coke, the effect of which is to aerate it very thoroughly, whereby the aerobic microbes come into action, completing the good work, so that nothing is left except a clean, colorless and odorless liquid.
The bacteriologist recognizes in the process of sewage disintegration the work of two classes of bacteria, the aerobic or those bacteria that work by reason of air and do their work only in its presence and the anaerobic or those that work in the absence of air.
The essence of the system is the use of horizontal plates to receive and retain the deposit of solid matters in suspension in the sewage, so that they are decomposed or digested, after the settled liquid has been drawn off, by aerobic bacteria and other higher forms of life, including worms, all of which thrive only in the presence of air.
Palmer determined in experiments on pigeon-dung bates that there is considerable loss of nitrogen during the process, and recommended bating in pits from which the air was excluded as much as possible, both as effecting a considerable economy in the dung, and in excluding false ferments, which, he concludes, are mostly aerobic.
After the preliminary treatment above described, the sewage requires to be passed over finer filtering beds, in which aerobic microbes complete the purification by changing the dissolved organic matter into inert inorganic compounds, by the process known as nitrification.