TIME 3 



reign. By the side of this chronological table, another 

 series of lines shows the succession of the various 

 ministers, and a third shows the periods of war and 

 peace occurring during the respective epochs. 



Such a table expresses in the most lucid manner the 

 sequence of events. That such a mode of graphic 

 record has been neglected in France cannot be too 

 deeply deplored* A somewhat similar method was 

 utilized in France during the last century to express 

 the duration and sequence of certain acts. Vincent 

 and Goiffon * have represented by a chronological 

 record the phases of rest and motion of horses' feet, as 

 observed in their different paces. This mode of ex- 

 pression is surely preferable to that of language, when 

 it is a question of conveying to the mind the meaning 

 of complicated rhythms. 



Chronography. — The diagrams of which we have 

 just been speaking are, however, only one mode of 

 representation, clearer, it is true, than others, but 

 reliable only in so far as the data on which they 

 depend are trustworthy. In experiments, for instance, 

 which deal with time measurements, it is of immense 

 importance that the graphic record should be auto- 

 matically registered, in fact, that the phenomenon 

 should give on paper its own record of duration, and 

 of the moment of production. This method, in the 

 cases in which it is applicable, is almost perfect. In 

 other instances photography comes to the rescue, and 

 affords accurate measurements of time events which 

 elude the naked eye. The process which thus serves 

 to register the duration and sequence of events con- 

 stitutes a method called " chronography." 



We are about to explain this method, proceeding 



* Memoire artificielle des principesrelatifs a la fidele representation 

 des nnimaux tunt en peinture qu'en sculpture, par feu Goiffon et 

 M. Vincent. In-fol. 1779. 



