[ Voltmeters, Ammeters, Wave Meters, Frequency Meters, Altimeters, Goniometers, Instruments for Measuring Resistance, Instruments for Measuring Damping Effects, Instruments for Measuring the Intensity of Sound, Instruments for Measuring Distance, Instruments for Recording the Characteristics of Discharge Tubes, ] Instruments for Recording the Characteristics of Loudspeakers and Microphones, [ Assembled Photographic, Electrochemical ] and Electro-Mechanical Recorder Units [, Oscillographs, Instruments Used in the Art of Surveying Including Theodolites, Leveling Instruments, Sine Compasses, Instruments and Apparatus for Determining Angles and Dimensions, Instruments Used in the Art of Navigation for Determining Bearings on Sea Including Sextants, Compasses, Calculators, Sounding Instruments and Apparatus, Instruments and Apparatus Models for Demonstrating Physical Phenomena Including Apparatus for Demonstrating the Occurrence of Standing Waves Along Conductors and Apparatus, Cross-Sec]tional Demonstration Models of Ap[paratus such as Tubes, Loudspeakers, Microphones, Measuring and Indicating Instruments, Demonstration Boards for Assemblies of Circuits and Apparatus and the Connections Therebetween, Assembled Motion Picture Cameras and Motion Picture Projector Units, Apparatus for Producing and Reproducing Light-Sound Impressions on Paper and Film, and Apparatus for Remotely Reproducing the Setting of Measuring, Indicating and Recording Instruments ]