Through these pictures we gain a conception of the manner in which the present stars in the Milky Way have clustered out of the original misty chaos. We cannot avoid the idea of great exterior similarity between the lumps formed in curdling or souring milk and those which we observe in the Milky Way. The renowned French scientist Duclaux says in his micro-biology: “In milk, commencing to sour, but yet entirely liquid, we observe under the microscope a precipitation of tiny particles. To begin with they are seen with difficulty and are discovered only by slightly displacing the plane of vision. Later they develop into distinct grains, characterized by Brownian movements, just like small particles of clay.... Still later the phenomenon appears as a steady molecular agglomeration. The grains have the tendency of the clay particles to lump and precipitate.” The first condensation-nuclei in the mist-clouds are no doubt cosmic dust entering from without and perhaps also larger clusterings such as meteorites and comets. At the existing low temperature, surrounding gases condense into fluid state on the dust particles which by virtue of these moist shells are cemented into aggregations of such size that gravitation overcomes the repelling radiation pressure. Gravitation assisted by the retarding vapours further mass these aggregates together. This process of coalescence is accompanied by heat production. Finally, small stars are formed, then groups of such stars, while the spaces between, now comparatively devoid of matter, appear dark much as the whey between flocks of curd. As yet, the small stellar bodies are surrounded by quantities of dust and gas, which, however, with continued condensation become ever more rarefied. Even yet the big stars in Pleiades, belonging to the helium group, appear on the photographic plates interspaced with great patches of dust-clouds. These are now, however, so unsubstantial that they offer little impediment to the procession of the mighty stars. The condensation process may be greatly accelerated through the invasion of voluminous gas nebulæ similar to the Cocoon nebula. At last all gases in the new star condense, that is to say the shell of tenuous vapours and dust contracts to such an insignificant thickness that it cannot be seen except possibly from the immediate vicinity. Small bodies ingathered through friction against the remnants of the original extended wrapping wander as planets around the new sun, sweeping away the last traces of unattached matter. The condensation on the new orb leaves a “hole” in the nebulosity which in this way is transformed into stars and their satellites which emerge from the mist and scatter on the firmament. The Milky Way appears to be in a rather advanced stage of this evolution. The “infinitely small” presents occasionally surprising likeness to the “infinitely large.”