134 



OPTICAL PROJECTION 



such difficulties, and which enabled him to laugh at them. 

 He carries with him four iron legs lx T % inch in section, 

 turned out at the bottom into a toe, through which is a hole, 

 by which all four feet are screwed to the floor. That is 

 essential, as otherwise these narrow and somewhat spreading 

 legs would be liable to the same danger as the tripod stands 

 above condemned. The upper ends slip into iron sockets 

 carefully fitted to them, and screwed to the four lower corners 

 of the lantern box. The box has only to be mounted on 

 these legs, and these latter screwed to the floor, and the 

 whole is complete. If more height is required, the legs can 

 be stood upon a couple of benches in the manner above men- 

 tioned; and there is no practical danger then of an upset, as 

 the seats themselves define the places which the feet occupy. 



Another expedient often 

 employed belongs to the next 

 paragraph. 



73. The Lantern Box or 

 Cabinet. This can be made 

 in many different ways, and 

 should always be carefully 

 thought out by the owner 

 himself, hi relation to his 

 own apparatus and wants ; as 

 a great deal of his comfort 

 will depend upon it. Fig. 

 72 shows a general method 

 often adopted, in order to 

 serve as a higher stand for 

 the lantern. The main body 

 of the box is open at both 



FIG. 72.-Rising Cabinet ends and at ^16 top, and the 



ends E E, carrying the lid of 



the box L, slide up and down in grooves A B, A B, near the 

 ends inside of the two sides ; or it is better if the grooves are 



