Page:The evolution of worlds - Lowell.djvu/210

174 treats of what is general and cosmic in that evolution, as geology treats of what is terrestrial and specific in the history of one member of the class, our own Earth. The two do not interfere, as the one faces questions in time and space to which the other remains perforce a stranger. If the picture by the one be fuller of detail, the canvas of the other permits of the wider perspective. Certain events in the history of our Earth can only be explained by astronomy, as geologists have long since recognized. It is these that fall into our present province.

Geologists, however, have applied astronomy according to their own ideas. Either they called in aurists, so to speak, when what they needed was an oculist, or they went to books for their drugs, which they then administered themselves—a somewhat dangerous practice. Thus they began by displacing the Earth's axis in hope of effecting a result; not realizing that this would only shift the trouble, not cure it; in fact, make it rather worse. They next tried what De Lapparent, one of the most brilliant geologists of the age, calls "a variation in the eccentricity of the ecliptic joined to precession of the equinoxes,"—a startling condition unknown to astronomy which does not deal in eccentric planes, whatever such geometric anomalies may be, but by which its coiner evidently means a change in the