Patent ID: 6973739

Claim:
An instrument for measuring spread of a rigger which extends outwardly from one of two opposite sides of a boat for supporting an oarlock of the boat, the instrument comprising: an elongate base member for extending athwartships of the boat, the base member having first and second abutment elements spaced from one another for abutment with the two sides respectively of the boat, the second abutment element being movable longitudinally of the base member relative to the first abutment element for bringing the second abutment element into abutment with said one side of the boat while the first abutment element abuts the other, opposite side of the boat; an elongate measuring element that is longitudinally extendable from the base member to the oarlock of the rigger; and a limiting mechanism that is operative to limit the length of the measuring element extendable from the base member, the length of the measuring element extendable being limited by the limiting mechanism in dependence upon the spacing between the first and second abutment elements such that the extendable length is increased by half the amount of any increase in the spacing and decreased by half the amount of any decrease in the spacing.