(_e_) If the image is a small one, or it is very strongly refracted, the colored edges come together in the middle, and the mingling of the light yellow with the light blue produces _green_—a new color which did not appear so long as the light ground appeared in the middle. (_f_) If the refraction is still stronger, the edges of the opposite colors lap still more, and the green vanishes. The Newtonian theory cannot explain this, but it is to be expected according to Goethe’s theory. (_g_) According to Goethe’s theory, if the object were a dark one instead of a light one, and were refracted on a light surface, the order of colors would be reversed on each edge of the image. This is the same experiment as one makes by looking through a prism at the bar of a window appearing against the sky. Where in the light image we had the yellow colors we should now expect the blue, for now it is dark over light where before it was light over dark. So, also, where we had blue we should now have yellow. This experiment may be so conducted that the current doctrine that violet is refracted the most, and red the least, shall be refuted. (_h_) This constitutes the _experimentum crucis_. If the prism be a large water prism, and a black strip be pasted across the middle of it, parallel with its axis, so that in the midst of the image a dark shadow intervenes, the spectrum appears inverted in the middle, so that the red is seen where the green would otherwise appear, and those rays supposed to be the least refrangible are found refracted the most. (_i_) When the two colored edges do not meet in this latter experiment, we have blue, indigo, violet, as the order on one side; and on the other, orange, yellow, saffron; the deeper colors being next to the dark image. If the two colored edges come together the union of the orange with the violet produces the perfect red (called by Goethe “_purpur_”). (_j_) The best method of making experiments is not the one that Newton employed—that of a dark room and a pencil of light—but it is better to look at dark and bright stripes on grounds of the opposite hue, or at the bars of a window, the prism being held in the hand of the investigator. In the Newtonian form of the experiment one is apt to forget the importance of the dark edge where it meets the light. [For further information on this interesting subject the English reader is referred to Eastlake’s translation of Goethe’s Philosophy of Colors, published in London.] THE JOURNAL OF SPECULATIVE PHILOSOPHY. Vol. I. 1867. No. 2. SECOND PART OF GOETHE’S FAUST. [Translated from Rosenkrantz’s “Deutsche Literatur,” by D. J. Snider.]