2 Matching Results

Search Results

Advanced search parameters have been applied.

in subjects: "protractors"

Plotter.

Patent for an improvement in "surveying-instruments, and has for its object to produce a simple device whereby certain information can be obtained without the necessity of auxiliary calculations,” (lines 12-15) includes illustration.

Date: March 24, 1891

Creator: Smith, Valentine Hartgroves

Item Type: Patent

Partner: UNT Libraries Government Documents Department

Protractor.

Patent for a new and improved protractor. This design "is to make a protractor or plotter by which may be calculated the length of the base, perpendicular, and hypotenuse of a right-angled triangle where the latitude and departure or the altitude and depression are given" (lines 15-20). To this end, it consists, "with the semicircular protractor provided with a rectangular opening the edges of which are graduated, and centrally-pivoted vernier, of the departure-scale arranged to move up or down… more

Date: June 10, 1890

Creator: Dolman, John H.