Our French biologist is of the opinion that the artificial production of that marvel of marvels, the living cell, will yet take place in the laboratory. But the enlightened mind, he says, does not need such proof to be convinced that there is no essential difference between living and non-living matter. Professor Henderson, though an expounder of the mechanistic theory of the origin of life, admits that he does not know of a biological chemist to whom the "mechanistic origin of a cell is scientifically imaginable." Like Professor Loeb, he starts with the vital; how he came by it we get no inkling; he confesses frankly that the biological chemist cannot even face the problem of the origin of life. He quotes with approval a remark of Liebig's, as reported by Lord Kelvin, that he (Liebig) could no more believe that a leaf or a flower could be formed or could grow by chemical forces "than a book on chemistry, or on botany, could grow out of dead matter." Is not this conceding to the vitalists all that they claim? The cell is the unit of life; all living bodies are but vast confraternities of cells, some billions or trillions of them in the human body; the cell builds up the tissues, the tissues build up the organs, the organs build up the body. Now if it is not thinkable that chemism could beget a cell, is it any more thinkable that it could build a living tissue, and then an organ, and then the body as a whole? If there is an inscrutable something at work at the start, which organizes that wonderful piece of vital mechanism, the cell, is it any the less operative ever after, in all life processes, in all living bodies and their functions,--the vital as distinguished from the mechanical and chemical? Given the cell, and you have only to multiply it, and organize these products into industrial communities, and direct them to specific ends,--certainly a task which we would not assign to chemistry or physics any more than we would assign to them the production of a work on chemistry or botany,--and you have all the myriad forms of terrestrial life.