This class provides for means for determining the characteristicsand the mutual relation of points, lines, angles, surfaces, andsolids, considered as having no properties but those arising fromextension and difference of situation. It includes mechanicallyguided means for describing lines. Processes or methods are classified inthe appropriate subclasses with instruments unless specificallyprovided for by a process subclass. For the most part specific subclassesare not provided for compound instruments; but an invention comprisingmatter classifiable in more than one specific subclass is placed inthe subclass having the lowest number and cross-referenced intothe subclass or subclasses having the higher number or numbers.
(1)Note. This class includes the combination of recording meanswith significant measuring structures of the type provided for in thisclass.
(2)Note. The following matter is excluded: The measurement offluent material. Instruments falling in this class in combination withcheck-controlled means or in combination with a series of signalsexceeding two. Observation instruments in which the principle ofoperation depends upon diverting light. Means for guiding or stopping toolsother than scribers. Means for automatically assorting objects.Means connected with a device classifiable elsewhere to automaticallyindicate the relative position of movable parts of said device.(This does not refer to means connected with a device classifiableelsewhere to indicate the position of said device with relationto other things not a part of the device).