Cotton type rangefinder

[Lang]

Keith,

Very interesting. I suppose you could turn it on its side to measure the distance to another ship, because they knew the exact length - even enemy ships - but it does not seem to go high enough in the numbers. Maybe fighter pilots used it because they knew the wingspan of the enemy aircraft. Just hold the throttle in the left hand, the stick in the right hand and the rangefinder in the other hand.

Watts is still running, they make electronic navigation equipment now. A lot of our army prismatic compasses were made by Watts.

Lang

[Keith Webb]

It appears to be related to the Stadimeter which was used by ships in convoy to keep their appropriate distances.

The sliding scale is one of several differently calibrated carried within the instrument.

We learn something every day...