Henry Kater's telescope Robert Benoist showing the inside of a

showing the inside of a theatre and the reactions of different parts of the audience to the play

concerned at the possibility of friction between the two nations

it surrendered to the Allies and the Convention of Tientsin

View of the exterior of the hospital with figures and horse-drawn carriages

alis pentapetalis

Henry Kater's telescope Robert Benoist showing the inside of aTelescope used by Henry Kater for pendulum observations. Geodesist and metrologist Henry Kater (1777 1835) invented Kater's pendulum in 1817 which enabled the strength of gravity to be determined. This sight was used to view the pendulum during observations in order to avoid parallax error. ca. 1820