124 



Micrometer Screw Contact Calliper. A combination of a calliper 

 and a telephone. When the contact is loosely made, a 

 boiling sound is heard, which ceases when a firm contact is 

 made. See also Calliper. 



Micronometer. An instrument for noting minute portions of 

 time. 



Microphone. An instrument for increasing the intensity of low 

 sounds by communicating their vibrations to a more 

 sonorous body which emits a more audible sound. [26, ] 



Microscope. An optical instrument consisting of a lens or 

 combination of lenses for making an enlarged image of an 

 object which is too minute to be viewed by the naked eye. 

 [2, 3, 5, 8, 9, 13, 16, 17, 20, 21, 22, 26.] 



Microscope, Binocular. A microscope with two eyetubes, fitted 

 with eyepieces, for viewing the object through the object- 

 glass with both eyes at the same time. [2, 3, 5, 9, 15, 17, 

 20, 21, 22, 27.] 



Microscope, Greenough Binocular. A combination of two 

 microscopes, each with a set of erecting porro prisms, 

 giving a pronounced stereoscopic effect. [2, 3, 13, 26.] 



Microscope, Jointed. A pocket microscope in which the handle 

 and lens-holder shut down against the slide on which the 

 object pliers are adjustable. [2, 13, 21, 26.] 



Microscope, Lucernal. A form of microscope in which the object 

 is illuminated by means of a lamp and its image is thrown 

 upon a plate of glass connected with the instrument or on 

 a screen independent of it. [26.] 



Microscope, Reflecting. A microscope in which the image formed 

 by a small concave speculum may be viewed either by the 

 naked eye or through an eyepiece. 



Microscope, Solar. A microscope in which the sunlight is used 

 as an illuminant. An enlarged image of the object is pro- 

 jected upon a screen in a darkened room or dark box. 



Micro Spectroscope. A spectroscope arranged for attachment to 

 a microscope. See also Spectroscope. [2, 3, 14, 22, 26.] 



Micro Tasimeter. A tasimeter (q.v.) arranged for measuring very 

 small extensions. 



Micro-Telescope. A combination microscope and telescope suit- 

 able for botanical work. [2, 13, 21, 26.] 



Microtome. An apparatus for freezing preparations and cutting 

 sections of same for microscopic examinations. [2, 3, 4, 17, 

 19, 20, 22, 26.] 



Microtome, Becker's Freezing. [20.] 



Microtome, Cambridge Freezing. ! -/. 26.] 



Microtome, Cathcart's. [3, 26.] 



Microtome, Granta Bali-Bearing. 



Microtome, Swift's. [3, 22.] 



Microtome, Williams's. [3, 22.] 



Mileage Recorder. An instrument for recording distance in 

 miles travelled by a motor-car, etc. [16.] 



