Measures for Progress: A History of the National Bureau of Standards

126 ELECTRICITY, RAiLROADS, AND RADIO (1911-16)
equipment. Under Stratton, the lines of research at the Bureau were far
from rigid, and he worked hard to keep them from becoming so. After.
noons he toured the laboratories inquiring about the work in each, beginning
his tour the next day where he had left off the previous afternoon. In this
way he carried ideas and problems from one division to another. Thus it
was that Dr. Wilmer Souder, in the weights and measures division, hearing
of the extreme difficulty with cement sieve measurements, became interested
and devised new 100. and 200-line ruled scales for testing and certifying the
sieves used by the cement industry.52
Improved test procedures and instruments disclosed the need for
better understanding of the constitution and characteristics of cement
terials, and as.testing became routine, the Bureau extended its investigations.
A petrographic laboratory set up at Pittsburgh studied the raw materials of
cement, and an experimental cement plant with grinding apparatus and
rotary kilns made it possible to determine changes in cement properties by
various methods of manufacture. Next, Bureau staff members developed
a granulometric analyzer and separator, to study fine grinding of cement.
Before long the test principles and equipment developed for cement were
being applied to other building materials, to sands and silica cements, con-
cretes and concrete aggregates, mortars and plasters, stucco, marls, stones,
and paving blocks.
Meanwhile, engineers at the Bureau subjected blocks of concrete and
full-scale concrete columns to compression and tensile strength tests. The
group at Atlantic City, investigating the action of sea water on cements,
mortars, and concretes, established a second exposure station at Charleston,
S.C. At Pittsburgh and Washington studies were made of the effect of alkali
salts on cement, of temperature on its hardening, of the permeability of
cement to water, and its resistance to heat, moisture, and pressure. The
steady stream of reports announcing the results of these investigations brought
inquiries from architects, engineers, contractors, and builders for still other
tests and investigations that they were not equipped to make, and from the
general public, for help with cement problems in and around the home.
Much the same pattern of development, from simple testing of Gov-
ernment purchases to devising test procedures, new instrumentation, and
finally to the establishment of a full-fledged technological research program
in the product, occurred in other materials used in large quantities by Gov-
ernment agencies—in clays and clay products including brick, building tile,
porcelain, terra cotta, fire clay, glass, and white-ware china; in lime, lime
mortar, and gypsum; protective coatings such as asphalt, felt, paints, oils,
"NBS C39, "Specifications for and measurement of standard sieves" (1912); cor-
respondence in NES Box 19, IWL; interview with Dr. Souder, Jan. 16, 1961.