Books Books ... regular helix lies on a circular cylinder. Let a be the radius of the circle thus formed by the axis of the closed helix ; let r denote the radius of the cross section of the ideal toroid on the surface of which the helix lies, supposed small in comparison... Philosophical Magazine - Page 102
1880 ## Proceedings, Volume 9

...revolution of a circle round any line in its plane not cutting it. Any simple on a circular cylinder. Let a be the radius of the circle thus formed by the...to the normal section of the toroid. We have 2ira a ., tan 6 5=^-= — N.2irr because -=^- is as it were the step of the screw, and 2irr is the circumference... ## Proceedings of the Royal Society of Edinburgh, Volume 9

...helix, because it lies on a toroid * just as the common regular helix lies on a circular cylinder. Let a be the radius of the circle thus formed by the...supposed small in comparison with a; and let 6 denote the iaclination of the helix to the normal section of the toroid. We have 2ira a tan 6 = N.27rr Nr ' because... ## Philosophical Magazine

Physics - 1880
...of the toroidal substance ; and the area of the inner one of the two is a section of the aperture. Let a be the radius of the circle thus formed by the...lies, supposed small in comparison with a ; and let 0 denote the inclination of the helix to the normal section of the toroid. We have , „_ 2-rra _ a... 