Miscellaneous Implements Exhibited at Cambridge. 473 
convenient and conspicuous position as an ordinary thermometer. 
It records the exact position in the house in which the fire has 
broken out, and automatically gives the alarm by means of a gong 
placed above the front door on the outside, simultaneously with 
another gong placed in any room of the house, and also with a 
gong affixed at the nearest fire station. There the street or 
house in which the fire has broken out is notified to the fire- 
man in charge by means of an indicating board. The exact 
position of the fire being thus shown to the fire brigade, valuable 
time may be saved by the accurate information and the earlier 
despatch of the fire engine, whilst increased possibility is thus 
afforded of curbing the dimensions of a fire. Those passing a 
house, on hearing the outside gong ringing, although no smoke 
Fig. 4. — McJannet's Weighbridge for Carts and Cattle. 
or flames may be visible, will be at once apprised of fire and 
ready to assist the inmates. The circuits in the house can be 
tested at all times. The efficiency of the thermostat is in no 
way impaired or affected by changes in barometric pressure, or 
by moisture in the atmosphere. It can be arranged to raise the 
alarm at any desired temperature, and is correct to one-tenth 
degree Fahrenheit. The apparatus cannot come into action 
except through an undue rise of temperature ; and the risk of 
false alarms, either through accident or tampering, is entirely 
obviated. The apparatus can also be applied to the purpose of 
detecting the heating of ships’ cargoes, the overheating of hay- 
ricks, &c. 
Article 1256. Mr. W. J. Burgess , Magdalen, King’s Lynn. 
Potato-Picking Machine, “ Pioneer.” Price 20?. — This machine 
