And Dec. of the object to be observed, the scale divisions to be pointed upon, and thus, in measures of distance, with the aid of the chronograph and printing micrometer, enable the observer to adjust the instrument for observation and obtain a record of his observations without the aid of a hand-lamp or the necessity to make any records in his notebook.
From the so-called chronograph of the year 354 (Catalogue Liberianus) we learn that on the 13th of August, probably in 236, the bodies of the exiles were interred in Rome and that of Hippolytus in the cemetery on the Via Tiburtina.
Abandoning therefore all a priori theoretical assumption, Bashforth set to work to measure experimentally the velocity of shot and the resistance of the air by means of equidistant electric screens furnished with vertical threads or wire, and by a chronograph which measured the instants of time at which the screens were cut by a shot flying nearly horizontally.
The Number Of Revolutions And The Rise Of Temperature Were Recorded On A Chronograph Drum.
Formulae of the calculus of finite differences enable us from the chronograph records to infer the velocity and retardation of the shot, and thence the resistance of the air.
Greater accuracy may be attained with a revolving-drum chronograph first devised by Thomas Young (Lett.