173 



Thermostat, Electric. A thermostat in which the temperature is 



kept constant by the automatic regulation of the amount 



of current traversing a heating coil. [4, 13.] 

 Thermostat, Lowry's New Pattern. An apparatus designed by 



Dr. Lowry to supply a rapid stream of hot water at a 



constant temperature. 

 Thermostat, Ostwald's Water. A thermostat consisting of a 



felt-covered copper vessel with gas regulator, Mker burner, 



and stirring arrangement. 

 Thomas Sinker. An improved form of sounding sinker (q.v.), 



with large tallow reservoir. [13, 28.] 

 Thompson Prism. See Prism. [2, 3, 22, 26.] 

 Thomson Calorimeter. See Calorimeter. [4, 15, 21.] 

 Thomson Deflector. See Deflector. 



Thomson Galvanometer. See Galvanometer. [4, 16, 19, 21.] 

 Thomson's Quadrant Electrometer. See Electrometer. [16, 21.] 

 Thorp Diffraction Grating. See Diffraction Grating. [3, 17.] 

 Thorp Diffraction Spectroscope. A spectroscope (q.v.) in which 



the dispersion is produced with a Thorp diffi action grating. 



[3, 17.] 



Thread Recorder. See Galvanometer. [4.] 

 Threlfall Micromanometer.- See Micromanometer. [4, 21.] 

 Thrust and Torque Dynamometer. See Dynamometer. [4, 16.] 

 Thunderstorm Recorder. 

 Thurston's Oil-Tester. See Oil-Tester. [13.] 

 Thurston's Recording Oil-Tester. See Oil-Tester. [13.] 

 Tide-Dial. A dial to exhibit the state of the tides at any time. 



[13, 15, 17.] 

 Tide-Gauge. An instrument to measure the rise and fall of the 



tides. See Gauge. [13, 15, 16, 17, 21, 24, 26.] 

 Tide-Indicator, Lenthall-Baugh. An instrument for giving the 



height of the tide above low-water level of ordinary spring 



tides at any hour between high and low water, and also the 



time from high water that the tide should be at any given 



height. [13.] 



Tide-Predicting Machine. See Harmonic Analyser. 

 Tide-Recorder. A tide-gauge which gives continuous records 



of the rise and fall of tides. [4, 6, 13, 15, 16, 17, 21, 26.] 

 Tide-Recorder, Field and Oust. An improved form of tide- 

 gauge, worked by compressed air, for use on a coast or on 



a ship. 

 Tide Table. Capt. Grant's " De Piano " model. A table for 



giving immediately the time of high water at the most 



important ports throughout the world. 

 Timber Contenting Rule. A slide-rule for denoting the content 



of timber in cubic feet. [15, 21.] 

 Timber Rod. A jointed deal rod with hook at one end, for 



ascertaining the length of standing timber. [15, 21, 24.] 



