CALIBRATION SUPPLIES
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Establissements A. Jowa, 105 Rue Bemel, Bruxelles 15, Belgium.
(Agents for the Zeefplatenfabriek Veco, Holland.)
Mason and Morton Ltd., Vandon St., Buckingham Gate, London,
S. W. 1. (English agents of the Zeefplatenfabriek Veco, Holland.)
Gunther Frey, Berlin-Britz, Walkenrieder Str. 19.
See also the Ernest F. Fullam Co., Ladd Research Industries, Inc., and
some microtome manufacturers.
Apertures
Platinum apertures are commonly available from the companies which
manufacture microscopes. The Canal Instrument Company also distributes apertures in most common sizes including those to fit their own
accessories. Both the Ernest F. Fullam Inc. and Ladd Research Industries
Inc. market apertures to fit most microscopes. G. F. Burger, 20 St. Martin's
Road, Merchantville 9, N. J., manufactures apertures. In England, apertures are available from the Aeon Laboratories, Beech Hill, Englefield
Green, Egham, Surrey.
Calibration Supplies
Ernest F. Fullam Inc., P. O. Box 444, Schenectady 1, N. Y. (Supplies
shadowed carbon replicas of calibrated diffraction gratings.)
Physical Research Laboratory, The Dow Chemical Co., 2-280 Bldg.,
Midland, Mich. (Supplies gratis samples of monodisperse polystyrene
latexes. Nine different sizes are currently available.)