Fecha de publicación: 06/11/1913 Fuente: WIPO "pollen" 14,305. Pollen, A. H., and Isherwood, H. June 22. Plane-trigonometry calculators.-Relates to improvements in apparatus described in Specification 13,082/06 for ascertaining subsequent ranges of a distant ship when there are known its preliminary range, its speed, course and bearing and the speed of the observing ship. The model Y of the observing ship is carried on a graduated disk 22 and points to zero, this disk being set to the bearing of the distant ship with respect to the base bar 5 on which a slide 7 sets out the range. The presentation of the distant ship is given by two points ZZ' moving together and directly over one another, but spaced apart so that the bar 14, for instance, on which the speed of the ship Y is set out may, if need be, pass through the point Z. The speed of the target is set out on an arm 12 passing through the point Z and its course is set with respect to a graduated circle 15 carried on the arm 14. The arm 14 is kept parallel to the direction of the ship Y by means of three pulleys 24, as shown, on arms 21 driven by inextensible belting, the arms also serving to carry the chain drive 19 for the pinion 36 which moves the slide 17 along the arm 14 to the proper speed. The lazy-tongs 29 is arranged as shown and to enable a reading to be taken on the graduated glass cover W, although the lazy-tong projects outside on first setting, the arm 5 carrying all the linkages is adapted to pivot round the point Y. A scale 26 is provided as before.