Chapter II: Section I: Rubber Motors

§ 1. Some experiments with rubber cord. § 2. Its extension
under various weights. § 3. The laws of elongation
(stretching)--Permanent set. § 4. Effects of elongation on
its volume. § 5. "Stretched-twisted" rubber cord--Torque
experiments with rubber strands of varying length and number.
§ 6. Results plotted as graphs--Deductions--Various
relations--How to obtain the most efficient
results--Relations between the torque and the number of
strands, and between the length of the strands and their
number. § 7. Analogy between rubber and "spring"
motors--Where it fails to hold. § 8. Some further practical
deductions. § 9. The number of revolutions that can be given
to rubber motors. § 10. The maximum number of turns. § 11.
"Lubricants" for rubber. § 12. Action of copper upon rubber.
§ 12A. Action of water, etc. § 12B. How to preserve rubber.
§ 13. To test rubber. § 14. The shape of the section. § 15.
Size of section. § 16. Geared rubber motors. § 17. The only
system worth consideration--Its practical difficulties. § 18.
Its advantages 24