The line of consideration pursued in the last part of this chapter has led us from certain observations in the plant kingdom, concerning the coming into being of ponderable matter from 'nothing', to a corresponding picture of the earth's meteorological sphere. When discussing the plant in this respect we found as an instance 'worth a thousand, bearing all within itself the case of Tillandsia and more particularly the surprising appearance of phosphorus in it. Now, in the meteorological realm it is once more phosphorus which gives us an instance of this kind. For there is the well-known fact of the presence of phosphorus in conspicuous quantities in snow without a source being traceable in the atmosphere whence this substance can have originated in ponderable condition. The phosphorus appearing in snow, therefore, brings before our very eyes the fact that the heights of the atmosphere are a realm of procreation of matter. (In our next chapter we shall learn what it is in phosphorus that makes it play this particular role in both fields of nature. What interests us in the present context is the fact itself.)