orders the nearly symmetrical, star-like figures of the flowers of the field, as well as of the sea, and which produces in the shell such an exquisite conical spiral that excels the most beautiful masterpieces of Gothic architecture?  In all these objects the geometrical form is the simple and necessary consequence of the principles and laws which govern the physical and physiological world.  That these principles and these laws are but an indication of a higher intelligent Power we may admit, but this has nothing to do with the present argument.

Having regard, then, for the principle that in the explanation of natural phenomena it is universally agreed to begin with the simplest suppositions, the first hypotheses of the nature and cause of the geminations have for the most part put in operation only the laws of inorganic nature.  Thus, the gemination is supposed to be due either to the effects of light in the atmosphere of Mars, or to optical illusions produced by vapors in various manners, or to glacial phenomena of a perpetual winter, to which it is known all the planets will be condemned, or to double cracks in its surface, or to single cracks of which the images are doubled by the effect of smoke issuing in long lines and blown laterally by the wind.  The examination of these ingenious suppositions leads us to conclude that none of them seem to correspond entirely with the observed facts, either in whole or in part.  Some of these hypotheses would not have been proposed had their authors been able to examine the geminations with their own eyes.  Since some of these may ask me directly, “Can you suggest anything better?” I must reply candidly, “No.”

It would be far more easy if we were willing to introduce the forces pertaining to organic nature.  Here the field of plausible supposition is immense, being capable of making an infinite number of combinations capable of satisfying the appearances even with the smallest and simplest means.  Changes of vegetation over a vast area, and the production of animals, also very small, but in enormous multitudes, may well be rendered visible at such a distance.  An observer placed in the moon would be able to see such an appearance at the times in which agricultural operations are carried out upon one vast plain—­the seed-time and the gathering of the harvest.  In such a manner also would the flowers of the plants of the great steppes of Europe and Asia be rendered visible at the distance of Mars—­by a variety of coloring.  A similar system of operations produced in that planet may thus certainly be rendered visible to us.  But how difficult for the Lunarians and the Areans to be able to imagine the true causes of such changes of appearance without having first at least some superficial knowledge of terrestrial nature!  So also for us, who know so little of the physical state of Mars, and nothing of its organic world, the great liberty of possible supposition renders arbitrary all explanations