50 L. Waldo—New Position Micrometer. 
webs, is cut its whole length as a matrix through which the 
screw works; and in order that this frame shall have no dead 
bis 
motion, there is a small matrix, n, about 1 mm. distant from it, 
at 
ia 
“s 
f ae noroeregay —— — ft 
t 2 
The end of the screw at Sis held firmly against an adjustable 
ate plane at p, by means of a secon ing a which acts 
An adjustable agate jewel at J is the only point upon which 
the frame rests upon its box; and as pointed out by Lord 
