155 



Siemens's Water Pyrometer. A calorimetric pyrometer in which 



temperatures are measured by the heating of the water in 



a calorimeter consequent upon the introduction of a nickel 



cylinder which has been allowed to acquire the temperature 



of the hot body. See also Pyrometer. [5, 13, 17, 21.] 

 Sight Clinometer. A clinometer (q.v.) for use with a gun-sight, 



more especially the rocking bar sight. [3, 5, 13, 15, 17, 21, 



25, 27.] 



Sight, Dial. See Dial Sight. [3, 11, 13, 15, 20, 21.] 

 Sight-Rule, Traver's. A sight-rule for use on a plane table 



with an adjustable parallel bar. [13, 15, 27.] 

 Sighting Telescope. See Telescope. [1, 2, 3, 8, 9, 11, 13, 16, 17, 



18, 20, 21, 22, 23, 25, 26, 27.] 

 Signal Station Telescope. See Telescope. [1, 2, 3, 8, 9, 13, 15, 



17, 18, 20, 25, 26, 28.] 

 Silver Voltameter. See Voltameter. [4.] 

 Silvered Mirrors. Optically worked glass silvered mirrors. [1, 



3, 10, 11, 13, 15, 17, 20, 21, 26.] 

 Simmance-Abady Combustion Recorder. See CO, Recorders. 



[13.] 

 Simmance-Abady Corrosive Gas Analysers. Used in paper mills, 



pyrites, burning plants and chemical works. See Gas 



Analysis Apparatus. [13.] 



Simmance-Abady C0 2 Recorders. See C0 2 Recorder. [13.] 

 Simmance-Abady Dead Beat Gauges. For recording pressure 



and vacuum of any range for all purposes. See Gauge. [13.] 

 Simmance-Abady Lamp Spinner. See Lamp Spinner. [13.] 

 Simmance-Abady Ventilating Hygrometer. See Hygrometer. [13.] 

 Simple Pendulum. See Pendulum. 

 Sine-Galvanometer. See Galvanometer. [19.] 

 Sinker, Fairy. A form of sounding sinker for securing samples 



of the sea bottom, without the use of the usual tallow arming. 



[13, 28.] 



Siphon Barometer. See Barometer. [6, 13, 16, 17, 21, 28.] 

 Sismograph. See Seismograph. [13.] 

 Sismometer. See Seismometer. [13.] 



Six's Maximum and Minimum Thermometer. See Thermometer. 

 Slide-Rule. A mathematical instrument consisting of two 



graduated parts, one of which slides upon the other, for 



the mechanical performance of addition and subtraction, 



and, by means of logarithmic scales, of multiplication and 



division. [2, 5, 6, 10, 13, 15, 16, 17, 20, 21, 24, 25, 27, 28.] 

 Slide-Rule, Anderson. A slide-rule with the scale in four 



sections. [13, 15, 20.] 

 Slide-Rule, Atmospheric. A slide-rule used in gunnery, giving 



the corrections to apply to the fuse for atmospheric temper 



ature and pressure. [13, 15, 27.] 

 Slide-Rule, Bain's. [15.] 

 Slide-Rule, Beghin. [15.] 



