"If flour be wetted with water, and the mixture closed up, it will be found, after some little lapse of time, by the aid of a microscope, to have produced organized beings that enjoy life, of which the water and the flour were believed incapable: it is thus that inanimate matter can pass into life, or animate matter, which is in itself only an assemblage of motion. Reasoning from analogy, which the philosophers of the present day hold perfectly compatible, the production of a man, independent of the ordinary means, would not be more marvellous than that of an insect with flour and water. Fermentation and putrefaction evidently produce living animals. We have here the principle; with proper materials, principles can always be brought into action. That generation which is styled _equivocal_ is only so for those who do not reflect, or who do not permit themselves, attentively, to observe the operations of Nature." This passage is much ridiculed by Voltaire, who asserts that it is founded on some experiments made by one Needham, who placed some rye-meal in well-corked bottles, and some boiled mutton gravy in other bottles, and found that eels were produced in each. We do not know sufficient of the history of Needham's experiments, either to affirm or deny their authenticity, but we feel bound to remind our readers of the much-decried experiments conducted by Mr. Crosse, and which were afterwards verified by Mr. Weekes, of Sandwich. In these cases, insects were produced by the action of a powerful voltaic battery upon a saturated solution of silicate of potash, and upon ferro cyanuret of potassium. The insects were a species of acarus, minute and semi-transparent, and furnished with long bristles, which could only be seen by the aid of the microscope. The sixth chapter treats of man, and the author thus answers the question, "What is man?":-- "We say he is a material being, organized after a peculiar manner, conformed to a certain mode of thinking, of feeling, capable of modification in certain modes peculiar to himself, to his organization, to that particular combination of matter which is found assembled in him. If again it be asked, What origin we give to beings of the human species? We reply, that like all other beings, man is a production of nature, who resembles them in some respects, and finds himself submitted to the same laws; who differs from them in other respects, and follows particular laws determined by the diversity of his conformation. If then it be demanded, Whence came man? We answer, our experience on this head does not capacitate us to resolve the question; but that it cannot interest us, as it suffices for us to know that man exists, that he is so constituted as to be competent to the effects we witness." In the seventh chapter the author, treating of the soul and spirit says:--