MEMORANDA. 1 
plane expanded likewise to double the size. The effect was still 
more striking when I superposed each third. 
In the latter case the size of the holes was SO Od 
colossal. When I say I have performed 1000 experiments 
in this direction, I do not in the least degree exaggerate. 
Tending to the same point were experiments made in 
taking stereoscopic pictures with one camera (single). If I 
take two landscapes without moving the camera, 7. e. at the 
same angle, and combine them in the stereoscope, all objects 
near at hand and afar off are projected upon the same plane, 
so that a person standing, say fifty yards from the camera, 
and say fifty yards nearer than a house, he seems in absolute 
contact with the house, and therefore, of course, immensely 
large. The same experiment succeeds, though not so strik- 
ingly, by taking two cartes de visite from the same negative, 
and superposing them in the stereoscope. 
On the contrary, if two pictures be taken of the same view 
and of not very distant objects, at a large angle, say ten or 
twenty yards, the combined picture, instead of being a true 
representation of nature, is nothing more than a small model, 
and the nearest objects almost seem to touch the nose. The 
conclusion, therefore, to be drawn from these experiments is 
this—the larger the angle the nearer the objects, and the smaller ; 
and, conversely, the smaller the angle the more distant the 
objects, and the larger they are. This I have proved in in- 
numerable instances, and in no simpler way than the follow- 
ing :—Frequently, when I am reading the services of the 
Church, my eyes almost touch the words, then the words are 
extremely minute; but instead of being apparently on the 
surface of the paper, they are suspended in the air, about 
midway between the surface and my eyes, and surrounded 
with intense lustre. If, without converging the optic axes, 
I shut one eye and look at the letters with the other near, 
they are, of course, magnified im proportion to nearness. 
Besides, if I take a pair of stereoscopic pictures, and make a 
very sudden effort at superposing them, instead of getting 
the usual effect, the combined picture is suspended midway 
in the air, and, as I said before, almost buried in lustre. 
And now to the microscope (the binocular). When the 
rays from the object emerge from the left-hand tube (en- 
closed) they do so at a great angle, and therefore, according 
to what I have shown, the picture is formed near the eye, 
and comparatively small, notwithstanding the magnifying 
power of the glass. If the left-hand eye-piece be brought to 
a state of nearer parallelism with the right-hand or vertical 
one, the angle of emergence will be diminished, and the pic- 
