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R
Rotary Table
Rosin: Also colophony, hard, brittle, translucent, usually amber-colored
resin, which is obtained as the residue in the distillation of turpentine.
The rosin prepared from exuded, or gum, turpentine is called gum rosin;
that obtained from extracted, or wood, turpentine is called wood rosin.
Rosin has a specic gravity of about 1.08. It is soluble in alcohol, ether,
and other organic solvents and is insoluble in water. Rosin softens when
heated to about 80°C (about 176°F) and melts between 120 and 135°C (248
and 275°F). It is one of the most important resins commercially and is used
extensively in making varnishes, pa ...