“Dust to dust, the mortal dies, both the foolish and the wise.” Psalter 136.
“Where is the dust that has not been alive? From human mold we reap our daily bread.” Young.
Again the eager farmer turns to plow the apparently lifeless soil. Possibly he observes a few worms and small bugs but aside from this the ground appears dead. If he would but examine a small portion of it under a microscope he would readily see that it is literally teeming with microscopic animal and plant life which is busily engaged in decomposing organic matter.
What happens to the stubble of the grain, the weeds, the fallen fruit, and the waste products of animals? All of this organic material must again be converted into its elements so that it can be used by new plants. This process of decomposition requires a variety of organisms as well as a variety of appetites.
Have you ever smelled the “rotten egg” like odor given off by decaying plants and animals? This is hydrogen sulfide gas which serves as food for a certain family of bacteria. Another group of bacteria lives on wet paper, cotton and rope for it digests the cellulose. Even from the depths of the ground bacteria have been discovered which live in crude petroleum. Possibly some of you have heard of bacteria, found in certain wells, which live on iron and produce a reddish corrosion on the lavatory fixtures. One of the strangest diets of all is that of a unique group of microbes which live on carbolic acid.
Molds are universally present in the air and soil, and they need very little food to carry on their destructive life. Moisture seems to be their chief concern for their appetite is very adaptable. Because of the rapid growth and preference of molds for darkness and moisture the tiller of the soil greatly fears a damp season.
A little known but very important group of micro-organisms are the actinomycetes which occupy a place between the bacteria and the molds. Research in the last decade has revealed their important position in nature. They also are universally found and occupy a place in the upper strata of the soil where they are engaged in breaking down and consuming dead plant and animal material. Many secrete substances which destroy other harmful bacteria.
Most of these micro-organisms have amazing appetites. They have no fixed mealtime as humans do but they eat continuously. In fact some consume twice their weight in sugar every hour. The amount that these small creatures consume can be tested by delicate instruments and fairly accurate computations can be made as to their food consumption. When one stops to consider that the average cubic inch of crop and pasture land contains from 50 to 160 million bacteria alone one realizes the significance of the title—“Living Dust”—for the earth teems with hidden life. When the useful bacteria which are found in the soil, water and intestines of animals and humans are compared numerically with the disease producers they out number them 30,000 to 1. In this season of Spring and new life it is indeed wonderful to behold the unfolding leaves and the growing plants but let us not be unmindful of the “Living Dust.”