In the further experiments which this query gave rise to, we meet with another illustrious Catholic name, that of Theodor Schwann, better known as the originator of that fundamental piece of scientific knowledge, the cell-theory. Theodor Schwann (1810-1882) was born at Neuss and educated by the Jesuits, first at Cologne, afterward at Bonn. After studying at the Universities of Wuerzburg and Berlin he became professor in the Catholic University of Louvain, where his name was one of the principal glories of this now wrecked seat of learning. Thence he went as professor to Liege, where he died. He was, says his biography in the _Encyclopaedia Britannica_, "of a peculiarly gentle and amiable character and remained a devout Catholic throughout his life." Schwann's experiments tended to show that the introduction of air--of course containing oxygen--did not lead to the production of life, if the air had first been thoroughly sterilised. It was thought that this question had been finally answered, when it was reopened by Pouchet, in 1859. He was a Frenchman, the director of the Natural History Museum of Rouen, but as to his religious views I have no information. It is quite probable, however, that he was a Catholic. Pouchet and all on his side were finally--so far as there can be finality in such a matter--disposed of by Pasteur, of whose distinction as a man of science and devoutness as a Catholic nothing need be said. It is quite unnecessary to devote any consideration here to the character of Pasteur's experiments, for they have become a matter of common knowledge to all educated persons. Let it suffice to say that they were on the lines first laid down by Redi and greatly elaborated by Spallanzani, namely the exclusion from the fluids or other substances under examination of all possible contamination by minute organisms in the air. Spallanzani knew nothing of these organisms; they were not discovered until many years after his death. But he surmised that there was something which brought corruption into the fluids; he excluded that something, with the result that the fluids remained untainted. From our point of view, however, there are several things to be learnt. In the first place quite a number of ignorant persons have thought that the discovery of spontaneous generation would upset religious dogmata. That of course is quite absurd. From what has been said above it will be seen that St. Thomas Aquinas--in common with all the men of learning of his day--fully believed in it, as did Needham, another ecclesiastic as to whose orthodoxy there is no doubt. Further, the entire controversy is a complete confutation of the false allegation that between Catholicism and science there is a great gulf set. There have been few longer and more remarkable controversies in the history of science, and scarce any other--if indeed any other--which has such important bearings upon health and industry than that which relates to bio- or abio-genesis. It