Tee Bee,
What you have is an original Gotham Hobbie Deezil .12ci produced around 1948-9 m unfortunately due too poor quality control most will not run, or run poorly. Good reproductions/replicas that do perform were made by Gordon Burford and currently CS , alternatively if your a machineist Rodger Schroder offers a casting kit and full construction drawings and step by step machineing guide.
Stewart