Balloon theodolite by Cary

1938

Balloon theodolite by E.R. Watts & Son

1917

Pilot balloon theodolite

Balloon theodolite by E.R. Watts & Son

1940

Balloon theodolite by Cary

1935

Pilot balloon theodolite by Otto Fennel Sohne of Kassel

1939

Balloon theodolite Mark D by Cary

1935

Balloon theodolite by Cary

Pilot balloon theodolite by Cary & Co.

Pilot balloon theodolite

Balloon theodolite

1955-1960