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SUMMARY OF CURRENT RESEARCHES RELATING TO 
1 m. in length on which run independently the frame carrying the 
bellows and the wooden plate which supports the cast-iron stage carry- 
ing the stand. At one extremity of the frame carrying the bellows is fixed, 
the small mouth of the bellows, while the other extremity is attached 
to a smaller frame sliding in the first, and can be fixed in any position 
by a clamping screw. The total length of the bellows is about 0*70 m. 
The arrangement for moving the micrometer screw at a distance is very 
sensitive. The camera is provided with a ground-glass plate and trans- 
parent plate, and with slides of sizes 9 by 12, 12 by 16, and 18 by 18 cm. 
