Figure 10.—Chart from Secci's meteorograph. (From Lacroix, op. cit. footnote 22.)
As has been indicated, the Signal Corps used all six systems, a panoply of gadgetry which must have been wondrous to behold. Its Secci meteorograph, which had attracted much attention at Paris, was estimated to have cost 15,000 francs. Abbe reported in 1894 that the instruments were long kept in the apparatus room "as a fascinating show to visitors and a stimulation to the staff in the invention of other instruments."[31]
Figure 11.—Draper's mechanical registering barometer, as used in the Lick Observatory. (Photo courtesy Lick Observatory.)
Figure 12.—Hough's electromechanical registering barometer, about 1871.