Cherubin, whose in strument consisted of two inverting systems, and consequently gave a totally wrong impression of depth, i.e.
13 that the objective's exit pupil P'P1' is portrayed by the positive eyepiece, the image P"P i " limits the pencils P ', double microscope; these inverting prisms permit a convenient adaptation of the instrument to the interpupillary distance of the observer.
Then, by inverting the series, the longitude was expressed in terms of the time.
The question therefore arises, how we are to discover "All M is P," and this question Wundt answers by adding an inductive method, which involves inverting the inductive syllogism in the style of Aristotle into a deductive syllogism from a hypothesis in the style of Jevons, thus: - (I) (2) S is P. Every M is P.
The inverting telescope, composed of two, convex lenses, was a later invention; still it is not impossible that the original experiment was made with two convex lenses.