DECIMAL CLASSIFICATION 
681.15 
151 
.I52 
153 
I54 
.I55 
150 
2 
41 
411 
A412 
413 
414 
415 
416 
42 
Toys and apparatus with automatic mekanical movements 
See also 681.82 Automatic musical instruments 
Automatons imitating human actions 
Automatic animals 
Complex toys imitating actions of persons and animals 
Automatic machines and apparatus moving on the ground 
Carriages, wagons 
Automatic animals and apparatus moving in water 
Fish; boats 
Automatic animals and apparatus moving in the air 
Flying birds; balloons 
Scientific instruments of wood or metal for mesurements 
and observations 
Manufacture of the various instruments uzed in pure and applied science, to 
observ, ascertain, mesure or register, may be clast with the use of those instruments 
in 500-600 or (except those provided for under 681.3—.7) may be brought together 
here, the special kind of instrument being indicated by clas number for its use, 
following a colon; e. g. 681.2:534 Manufacture of acoustic apparatus, 681.2:617 
Manufacture of surgical instruments, 681.2:631.3 Manufacture of farm machinery 
Apparatus for glas blowing 
Glasblowing or enameling with blowpipe or lamp. See also 666.1-.2 
Special instruments may be clast under number for their use or may be brought 
together here, and distinguisht by affixing after a colon the number for use, as 
noted under 681.2 
Optical instruments Optician’s trade 
See also 522 Practical astronomy, 535.8 Applications of optics 
As noted under 681.2-.3, manufacture of instruments may be clast under number 
for their use or may be brought together here and subdivided by colon followd 
by number for use, e. g. 681.4:522.2 Manufacture of telescopes 
Various kinds of optic instruments 
Spectacles Eye glasses 
Instruments for distance observation 
Opera glasses; spy glasses 
Magnifying glasses 
Reading glasses: microscopes 
Spectroscopes 
Photometers 
Polarimeters 
Optic glasses 
Oculist’s glasses; plate glas; mirrors; prisms; lenses 
Frames and metal parts 
Optic screw 
Setting and adjusting