These are almost the words of a poet, and it is just this poet's imagination which urges him onward into science.[383] Face to face with the productions of nature he abounds in conjectures, comparisons; he gropes about, proposing explanations, making trials, extending his guesses like so many flexible and vibrating feelers into the four corners of the globe, into the most distant regions, of fancy and truth. As he looks upon the tree-like and foliaceous crusts which are formed upon the surface of freezing liquids, he asks himself if this be not a regeneration of vegetable essences, dissolved in the liquid. At the sight of curdling blood or milk, he inquires whether there be not something analogous to the formation of the bird in the egg, or to the coagulation of chaos which gave birth to our world. In presence of that impalpable force which makes liquids freeze, he asks if apoplexy and cataract are not the effects of a like power, and do not indicate also the presence of a congealing agency. He is in presence of nature as an artist, a man of letters in presence of a living countenance, marking every feature, every movement of physiognomy, so as to be able to divine the passions and the inner disposition, ceaselessly correcting and undoing his interpretations, kept in agitation by thought of the invisible forces which operate beneath the visible envelope. The whole of the Middle Ages and of antiquity, with their theories and imaginations, Platonism, Cabalism, Christian theology, Aristotle's substantial forms, the specific forms of the alchemists--all human speculations, entangled and transformed one with the other, meet simultaneously in his brain, so as to open up to him vistas of this unknown world. The accumulation, the pile, the confusion, the fermentation and the inner swarming, mingled with vapors and flashes, the tumultuous overloading of his imagination and his mind, oppress and agitate him. In this expectation and emotion his curiosity takes hold of everything; in reference to the least fact, the most special, the most obsolete, the most chimerical, he conceives a chain of complicated investigations, calculating how the ark could contain all creatures, with their provision of food; how Perpenna, at a banquet, arranged the guests so as to strike Sertorius; what trees must have grown on the banks of Acheron, supposing that there were any; whether quincunx plantations had not their origin in Eden, and whether the numbers and geometrical figures contained in the lozenge-form are not met with in all the productions of nature and art. You may recognize here the exuberance and the strange caprices of an inner development too ample and too strong. Archæology, chemistry, history, nature, there is nothing in which he is not passionately interested, which does not cause his memory and his inventive powers to overflow, which does not summon up within him the idea of some force, certainly admirable, possibly infinite.