To neither of these questions can Physical Science return a perfectly certain and definite answer. And it must be confessed that as far as our knowledge of Nature goes, those have the best of it who maintain first, that all existing Protoplasm implies pre-existing Protoplasm; secondly, that as to the method, the conditions of the real origin of Protoplasm nothing whatsoever is known; and thirdly, that, notwithstanding all assertions and experiments to the contrary, the origin of living things from dead and decaying organic matter (_i.e._, matter that has lived), or from inorganic matter under given conditions (spontaneous generation, generatio æquivoca, archebiosis) has never been proved and demonstrated in such a manner as to allow us no room for hesitation, no place for doubt. The difficulties and dangers besetting this thorny and much-vexed subject will be better understood if we institute a short examination into the history and present condition of the doctrine of Spontaneous Generation. It is certain from the results of astronomical and geological investigation, that at an exceedingly remote epoch, estimated by untold millions of years, the earth's surface was absolutely unfitted for the presence of life; nay, more, that even the laws of chemical combination were suspended, and in abeyance. After the glowing spheroid cooled down, and various chemical compounds were formed, life as a matter of fact made its appearance on the earth. Throughout the inorganic world the continuity is unbroken--the present is truly the child of the past. But in the organic world it is not so. Whether life arose in the natural course of universal law, or how it did arise, we cannot tell, scientifically, that is to say; no assertion, one way or the other, admits either of proof or disproof. There are absolutely no data to proceed upon. The very first organic remains discovered belong to a comparatively high type. It is as though in a garden every plant and bush burst at once into full flower, and never showed the flower in the bud.