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INDUSTRIAL RHEOLOGY

CHAPTER I

Historical Background. Rangę of Applicability of Rheologlcal Methods. Psychological Aspect. The Fluid State. Naturę of Viscosity. Poiseuille’s Law. Kinetic Energy and End-effect Corrections.

The manner in which materials flow, or resist the passage of bodies through them, has been a matter of interest from earliest times. Lucretius writes:—

“ For whatever things fali through water, or fine air, these must speed their fali in accordance with their weights, because the body of water and the thin naturę of air cannot delay each thing eąually, but yield sooner, overcome by the heavier.” ¹

On another occasion he speaks of the flow of materials:—

“ For water moves and flows with so very smali a moving power because it is madę of smali rolling shapes. But on the other hand, the naturę of honey has morę cohesion, its fluid is morę sluggish, and its movement morę tardy, for the whole mass of its matter coheres morę closely assuredly because it is not madę of bodies so smooth or so delicate and round.” ²

INDUS. RHEO.

1

"Derer. nat.,” II. 230 1 Translation Rouse.

2

* " De rer. nat.,” III. 189 j