244 BENJ. PIKE'S, JR., DESCRIPTIVE CATALOGUE. 



the opaque object, it is received by a mirror, M, placed in 

 the box, H I L X, which reflects the condensed light back 

 upon the face of the object, E. This mirror is adjusted to 

 a proper angle by the screw, S. 



Above the body A B E F is seen the part / V K which 

 carries the sliders or objects, and the object-glass or lens. 

 The tube, K, slides within the tube, V, and V again slides 

 into the box, H I L X. These tubes carry each a magnifying 

 lens. The inner tube, K, is sometimes taken out of the 

 other, V, seen within the box, and used alone. The sliders 

 and objects are introduced into a slit or opening at H. The 

 brass plate to the left of H is fixed to a tube h, by means 

 of a spiral wire within the tube, which presses the plate 

 against the side of the box H I L X, so that the sliders, when 

 placed in the opening, are pressed against the side of the 

 box. In using this microscope, the sun's rays are first made 

 to pass along the tube, A B C D, by the nuts Q and R. The 

 box for opaque objects, H I L X, is then slid by its tube, G, 

 into the tube, E F. The slider containing the object, having 

 its face to be examined turned to the right hand, is then 

 pushed into the opening at H, till the object is in the centre 

 of the tubes, V, K. The condensed light falling on the 

 mirror, M, is then thrown back on the face of the object in 

 the slider, and the door, k i, shut. Upon a white paper 

 screen or cloth, from four to eight feet square, and placed 

 at the distance of from six to ten feet from the window, the 

 observer, in the room made thoroughly dark, will see on the 

 screen a magnified representation of the object, which may 

 be rendered distinct at different distances of the screen, by 

 pulling out or pushing in the tubes, V, K, containing the 

 convex lenses. As the sun is constantly moving, its rays 

 must be kept in the axis of the tubes by now and then turn- 

 ing the nuts, Q and R. 



When the microscope is to be used for transparent objects, 

 the box, H I L X, with its tube, G, and other appendages, 

 is removed, and the apparatus shown at the side of the 

 instrument substituted for it. This is done by sliding the 

 tube, Y, into the tube, E F. A slider containing the mag- 

 nifying lens is then slipped through the opening at n, and a 

 second condenser may or may not be inserted in the opening 

 at h. The slider with the object is then placed in the open- 

 ing, m, and when its magnified picture falls upon the screen, 

 it is adjusted to distinctness by turning the milled nut, 0. 



