sight-hole

I was waiting very carelessly, being now a little desperate, at the entrance to the glen, instead of watching through my sight-hole, as the proper practice was.

Lorna Doone Richard Doddridge 2004

The officer of the gun sights through sight-hole, and orders

Ordnance Instructions for the United States Navy. 1866. Fourth edition. United States. Navy Dept. Bureau of Ordnance

It consists practically of an ordinary compass box with a prism and sight-hole at one side, and a corresponding sight-vane on the opposite side.

The Sewerage of Sea Coast Towns Henry C. Adams 1912

When looking through the sight-hole the face of the compass-card can be seen by reflection from the back of the prism, and at the same time the direction of any required point may be sighted with the wire in the opposite sight vane, so that the bearing of the line between the boat and the required point may be read.

The Sewerage of Sea Coast Towns Henry C. Adams 1912

This was covered thick with frost crystals, but Bobby breathed on them, and rubbed them with the heel of his palm, and so acquired a sight-hole.

The Adventures of Bobby Orde Stewart Edward White 1909

After more than two hours of incessant fighting, Lieutenant Worden having been temporarily blinded through the powder from an exploding shell which struck a sight-hole in the pilot-house of the "Monitor," through which he was watching the enemy, its command devolved upon Lieutenant Greene.

Thirteen Chapters of American History represented by the Edward Moran series of Thirteen Historical Marine Paintings Theodore Sutro 1886

I was waiting very carelessly, being now a little desperate, at the entrance to the glen, instead of watching through my sight-hole, as the proper practice was.

Lorna Doone; a Romance of Exmoor 1862

"A shell struck the forward side of the pilot-house directly in the sight-hole or slit, and exploded, cracking the second iron log and partly lifting the top, leaving an opening.

Famous Sea Fights From Salamis to Tsu-Shima John Richard Hale