634 SUMMARY OF CURRENT RESEARCHES RELATING TO 



the object-glass follow the motion of the tubes upon their hinges. One of 

 the two prisms is placed a little higher than the other, in order that the 

 rays may not pass between their angles, which may in this manner cross 

 each other more or less." 



Fig. 1, plate XII., represents a front view of another binocular Micro- 

 scope. The variable separation of the tubes t, t, as well as their draw- 

 ing motion, take place by means of the milled head E^, and by the 

 pinions i taking into racks fixed upon each of the interior tubes. The 

 prism p', which is conical, circular, concave, and truncated, reverses the 

 image by causing the rays to pass to the left which it has received from 

 the right, and those to pass to the right which it has received from the left. 



Figs. 2, 3, and 4 " show other arrangements of prisms or reflectors either 

 plane or curved, the object of which is to divide into two parts the rays 

 coming from an object-glass of any kind, and to render them binocular ; 

 this arrangement allows of the visual angle being preserved and the angle 

 of the two eye-tubes being equalized. Although two of the prisms or 

 reflectors are not placed in the same plane, they have nevertheless no in- 

 fluence upon the extent of the luminous rays and the dimension of the rays 

 which pass through them. A reverse threaded screw allows of the prisms 

 p,p^, being separated, and another similar screw serves also to move the 

 prisms p, p, into the positions shown at fig. 5, and which then furnish 

 images of another kind. With reflectors formed by a sector of a cylinder 

 (fig. 4) images " different from the preceding are obtained, and present 

 singular effects, " which with their applications form part of this invention." 



Fig. 6 represents a binocular Microscope with double object-glasses. 

 " The two tubes are made to suit the variable distance of the eyes of the 

 observer by turning the head of the long screw V^, which acts by means of 

 two different proportioned screw threads upon the arms h, h, ¥, b^, so that 

 the tubes t, t, can be made to recede from each other until the arms h, h^, 

 are parallel in two planes passing through their points of attachment, 

 without the object leaving the focus. Each tube is furnished with re- 

 volving object-glass holders having three or four object-glasses; this 

 might also be the case with the eye-pieces." The tubes of the object- 

 glasses are cut away when their focus is very short. 



Fig. 7 represents a portion of a Microscope for two persons to inspect 

 the same object at the same time. The lenses are slightly cut away. 



" Fig. 8 shows another modification of the binocular Microscope and is 

 intended to give views 6f the same object at different angles, so that the 

 relief of the object is considerably augmented." 



" Fig. 9 (plate XIII.) shows the mode of uniting a large number of 

 object-glasses, each of which gives a somewhat different view of the object. 

 Figs. 10 and 11 show how all these various views may be brought to bear 

 upon the same eye-piece or upon the same point, or upon different points. 

 These object-glasses may be made all to magnify to the same or to 

 different extents." 



" These binocular Microscopes having one or more object-glasses, or 

 having several object-glasses and one eye-piece, are also intended for 

 photographing objects, and for reproducing them with forms and reliefs 

 resulting from these arrangements. These views may be superposed 

 completely or partially, and be of equal or different dimensions, or 

 different views of the same object, but of such dimensions that those 

 which reproduce the same plans shall be larger or of greater magnifying 

 power, and the others smaller, or vice versa. They may be combined in 

 such a manner as to reproduce with incomparable perspective and fidelity 

 the object, scene, or landscape photographed or under view, and so that 



