The brassfounder's manual : instructions for the modelling, pattern-making, moulding, alloying, turning, filing, burnishing, bronzing, etc., etc. ... (1879)
Graham, Walter · London : Crosby Lockwood and Co. · leaf 36
ould, so as to occupy the exact position of the hole or opening, and prevent the metal or alloy from running into such space. In order to keep the core in its exact place, it is made a little longer than necessary, so as to have a bearing at each end. The pattern has in consequence prints upon it,… … Fig. 10.— Fake Cores.
Brass founders
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.