XI. TIME. 129 



503a. Marine Chronometers for ships' use. Manufactured 

 by Victor Kullberg, Liverpool Road, London, N. 



South Kensington Museum. 



503b. Two-day Chronometer, fitted complete. Two move- 

 ments reversed, to show the compensation balances. 



South Kensington Museum. 



503d. Chronometer and case 011 stand with glass shade. 



The Royal Observatory, Greenwich. 



509. Marine Chronometer, regulated at sidereal time, used 

 by the Scientific Commission of Noumea in observing the transit 

 of Venus. Messrs. Tondola and Co., Paris. 



510. Marine Chronometer, suitable for distributing the 

 hour in quarter minutes to an unlimited number of electric 

 receivers, going for one year without being wound up. (System 

 applied for more than three years with complete success.) 



Messrs. Tondola and Co., Paris. 



511. Marine Chronometer, regulated to mean time. Speci- 

 men of ordinary construction. Messrs. Tondola and Co., Paris. 



512. Geographical Clock, with revolving planisphere j 

 showing the time, longitude, and latitude, of all parts of the globe. 



Messrs. Tondola and Co., Paris. 



513. Astronomical Pendulum Clock. 



W. Brooking, Hamburg. 



514. Wheel-work of Clock. W. Brooking, Hamburg. 



515. Astronomical Pendulum Clock with mercury com- 

 pensation pendulum. Th. Knoblich, Hamburg. 



517. Chronometer-escapement, model. 



Th. Knoblich, Hamburg. 



518. Anchor-escapement, model. 



Th. Knoblich, Hamburg. 



519. Pendulum Clock belonging to the tide-gauge of Mr. 

 Reitz. Th. Knoblich, Hamburg. 



519a. Clock worked by Water-power. T. Hankey. 



520. Astronomical Pendulum Clock. 



F. Dencker, Hamburg. 



The Jiirgens compensation pendulum system has an isochronous sus- 

 pension spring, determined by calculation. It is, contrary to the formerly con- 

 structed repose pendulum, executed with sufficient stability. Not only is the 

 expansion coefficient of the separate bars exactly determined by the pyrometer, 

 40075. I 



