Mr. O'Hara stared at her, the cogs of thought turning.
From the gate road a heading called a bolt-hole is opened, and extended into a large rectangular chamber, known as a " side of work," large pillars being left at regular intervals, besides smaller ones or cogs.
It can seldom be obtained in large portions, and has the disadvantage of being apt to warp; its great hardness, however, renders it valuable for the manufacture of various articles, such as the cogs of mill-wheels, flails and mallets, and handles of hammers.
Separate teeth, fixed into mortises in the rim of the wheel, are called cogs.
The inking arrangements are usually very good, for, by a system of racks and cogs which may be regulated to a nicety, the necessary distribution of ink and rolling of the printing surface runs in gear with the travelling type bed or coffin.
