Anon. - INSTRUMENTS - BAROMETERS: Rules for Foretelling the Alteration of the Weather .... [London ?], unk. publisher, ca. 1730, h'bill., as issued ? First Edition ? Rare. See Middleton, Barometer; see Goodson, English Barometers. A very good copy with some overall toning.

A set of instructions for the use of a barometer. The instructions have been mounted both recto and verso on a card that is bordered with decorative marbled paper. Recto has the instructions for interpreting the movement of the mercury. Verso has detailed instructions on the use of the vernier and read outs. The instructions are written in a straight forward style and are based upon the printed work of Halley and Patrick (they are cited by name in the prefatory paragraph). Both men lived in the late 17th and into the first quarter of the 18th century. Patrick, the first English instrument maker to specialize in barometers, published two works on the barometer prior to 1704. Halley published an article on its use in 1700. Goodson points out that vernier readouts on barometers were not in general use until the mid 18th century. Given the detail of the instructions on the use of the nonius (vernier) it appears to have been a relatively recent improvement. In conjunction with the references to the publications of Halley and Patrick it is most likely that the card of instructions offered here dates from the earlier part of the 18th century. The card retains its original blue silk ribbon (to hang form the base of a barometer ?). A remarkable artifact. The card meas. appx. 5.25 x 8.5 inches.

$4,500