This nocturnal is made of boxwood, a popular material for English though not Continental nocturnal makers who instead prefered to use metal. Like a good deal of the astronomical instruments collection and by far the largest proportion of the nocturnal collection this instrument was purchased by James Caird from the early 19th century collector, Gabb.

Standard wooden nocturnal for use primarily with the Little Bear. Stars engraved on handle. Numbered scale for Little Bear is the outer one, inner scale is for Great Bear and is numbered clockwise from the top. Date scale has named months, meridian transit (lowest point) is at 28 October. Fixed disc also has numbered hour scale subdivide to 30 min and 15 min. Lunar-age scale is outer scale on rotatable disc with hour scale inside it. Two shaped pointers on rotatable disc; one with straight edge against the 12 line and one at approx 7:50