Twentieth century hand-book for steam engineers and electricians with questions and answers; a practical non-technical treatise .. (1913)
Swingle, Calvin Franklin, 1846- [from old catalog] · Chicago, F. J. Drake & company · leaf 389
the width of each steam port to be 1^/4 inches and the out-side lap to be 1 inch. In Fig. 118 the valve is at the ex-treme end of its travel towards the right and is about toreturn. It first covers port number one=:li4 inches. Nextit moves to mid travel lap number one=2i4: inches. Itsnext move is… … Fig. 119 uncovers port number two=4i/2 inches, which is its travel.To return to the third function of the valve or cut off.Fig. 119. The crank has now traversed 120°, and the high-est point of the eccentric is at 60° on the return circle, apoint equivalent to 240^ of the circle described by…
![An illustration from Cours d'architecture enseigné dans l'Academie royale d'architecture : premiere[-cinquième] partie ... (1675)](https://img.insideoutlibrary.com/img/200/ia-coursdarchitectu00blon-399-242.webp)
