Two micrometer surface testers used together and with electric bell system to measure divergence from flatness of large plane surfaces; designed and used by Dr. P.E. Shaw for experimental work in 1911. Micrometer surface testers 1911
Box for two micrometer surface testers used together and with electric bell system to measure divergence from flatness of large plane surfaces; designed and used by Dr. P.E. Shaw for experimental work in 1911. Two micrometer surface testers used together and with electr 1911