124 



Popular Science Monthly 



of water; in fact, the former may be 

 preferred to it, for, although it necessitates 

 a somewhat longer exposure, it is free from 

 evaporation and is not so likely to be 

 jarred out of place, on account of its 

 superior capillary attraction. 



At left: Microtomic cross-section of a rue 

 leaf. Right: The hair on the leg of a housefly 



A standard must next be constructed, as 

 shown at H, and /. No dimensions will be 

 given as the construction will vary with the 

 type of camera employed. Near the top of 

 the standard a 34-in. stovebolt, J, should be 

 inserted and screwed into the tripod 

 socket, thus holding the camera in place. 



The adjustable slide-holder is next to be 

 considered. Some time was spent and a 

 quantity of material utilized in devising 

 methods of construction for this important 

 part. The one which proved to be the most 

 successful is shown at K. It represents a 

 piece of H-in. wood (a cigar box will do) in 

 which a ij^-in. hole, L, was cut. On each 

 side of this hole a 5/32-in. bolt, M, was in- 

 serted and made stationary by the nuts N. 

 A long battery bolt will serve the purpose 

 excellently. Another piece of K-in. stock, 

 0, somewhat longer than the other, with a 

 i3^-in. hole as shown at T, was also made. 

 To one end of this second piece there was 

 nailed a 3^-in. square strip, P, which served 

 to fasten the whole part to the standard. 

 On either side of the ij^-in. hole of the 

 second piece, there was bored a hole cor- 

 responding to the bolts, M, and large 

 enough to permit them to slide up and 

 down easily. Springs, Q, were then 

 slipped on the bolts, which were in turn 

 passed through the corresponding holes in 

 O. Thumb nuts, R, such as are found on 

 batteries, were then screwed on the bolts. 

 By tightening or loosening the thumb nuts, 

 the slide-holder was adjusted to the lens. 

 A strip of spring brass, S, was then fastened 

 on K, to hold the slide rigid. When it was 

 desirable to use a color-screen in photo- 

 graphing or examining any object, the 

 filler was laid over the hole, T, on J. The 



adjustable holder was then mounted by 

 means of a strip, P, on the standard near 

 the lens U, in the shutter, V. On account 

 of the great magnification the focus is 

 necessarily very short; indeed, it has been 

 found that when a 6-in. bellows extension is 

 used, the focus is not quite 1/16 in. 



An adjustable mirror, W, must be 

 mounted on the standard base, H, by 

 means of an axle working on pivots in the 

 strip X. 



To operate, the object to be photo- 

 graphed must be placed on a thin glass 

 slide which should be fastened by means of 

 the spring brass clip, S, over the hole, L, in 

 strip, K. The bellows containing the 

 water lens must be extended as far as 

 possible. The mirror, W, should be 

 adjusted until the direct sunlight is reflected 

 through the slide into the camera. Focus- 

 ing is then accomplished by tightening or 

 loosening the thumb nuts, R, as the case 

 may be. The plate is then placed in posi- 



An ordinary camera attached to support for 

 making microscopic views with a water lens 



tion and the actual photographing carried 

 on as usual. An old magic lantern may be 

 used as the source of illumination; but 



