[ MEASURING AND SCIENTIFIC APPARATUS-NAMELY, ALL APPARATUS FOR MEASURING LENGTHS-NAMELY, DIAMETER GAUGES, LONGITUDINAL GAUGES, DEPTH GAUGES SUCH AS CALIPERS WITH THE NECESSARY HANDLES; ALL COMPARATORY GAUGES FOR CHECKING AND INSPECTING LONGITUDINAL GAUGES OR GAUGES MENTIONED ABOVE; APPARATUS FOR MEASURING DIMENSIONS AND CHECKING VERY SMALL ARTICLES-NAMELY, NEEDLES FITTED WITH POINTER GAUGES: ] GAUGES AND APPARATUS FOR CHECKING FIXED ARTICLES, FOR CHECKING MACHINE TOOLS SUCH AS CUTTERS, MILLING CUTTERS, AND DRILLS FITTED WITH MECHANICAL MEASURING APPARATUS; APPARATUS AS MENTIONED HEREIN FOR CONTROLING AND CHECKING THE BALANCE OR THE CORRECT RUNNING OF QUICKLY-REVOLVING MACHINE PARTS, [ FITTED WITH MECHANICAL GAUGES; DIAL GAUGES, GAUGES AS ENUMERATED ABOVE FITTED WITH OPTICAL APPARATUS, GASOMETERS AND GAS GAUGES; ] ELECTRIC MEASURING APPARATUS [ -NAMELY, AMMETERS, VOLTMETERS, PHASEMETERS ]