This Tycos Stormograph is a combination barograph and thermograph. This instrument makes a continuous recording of both temperature and barographic pressure over time, recording the results on a piece of specially made graphing paper. A barograph is an aneroid (without liquid) barometer with a clockwork driven drum, pen and chart. The pressure-sensitive element, a partially evacuated metal cylinder, is linked to a pen arm in such a way that the vertical displacement of the pen is proportional to the changes in the atmospheric pressure. The instrument is housed in a fine inlaid wood and beveled glass case, with a drawer for additional sheets of graph paper, which are also included. The barograph is marked for the maker, Tycos, and the cylinder is marked as made in Germany for the maker of the movement, Taylor Instruments, along with a retailer's mark, E.B. Meyrowitz Inc.
