此款斧型求積儀是由英國里茲T. R. Harding & Son公司所製造，其設計概念為英國人John Goodman於1896年發明。本體基本結構只有一支具弧形的金屬桿，弧形邊上刻有刻度。金屬桿的一端削尖做為追蹤點，另一端為邊緣銳利的斧型刀刃，目的為減少量測中的摩擦力。使用方式為，一開始將追蹤點放至曲線上，另一端斧形刀刃則放置於一任意點，作為起始位置。然後追蹤點沿著圖形邊緣繞一圈並將斧型刀刃的最終位置做上記號。最後，量測圓弧刀刃起始位置到最終位置的距離，再透過金屬桿上的刻度換算即可獲得面積。

This hatchet planimeter was manufactured by T. R. Harding & Son of Leeds, UK, based on a design concept invented by John Goodman in 1896. The main structure consists of a single curved metal rod with a scale engraved along the curved edge. One end of the metal rod is sharpened to serve as the tracing point, while the other end features a sharp hatchet, designed to reduce friction during measurement. To use it, start by placing the tracing point on the curve, with the hatchet positioned at any arbitrary point as the starting position. Then, trace the edge of the shape with the tracing point, and mark the final position of the hatchet. Finally, measure the distance between the starting and final positions of the hatchet, and use the scale on the metal rod to calculate the area.