Abstract: An endoscope assembly is disclosed having a housing adapted to be manipulated by medical personnel, such as a surgeon. An elongated lens tube has one end secured to the housing while the free end of the lens tube is adapted for insertion into a cavity of a body. At least one, and preferably several, lens assemblies are longitudinally slidably mounted within the lens tube and movable between longitudinally spaced positions within the lens tube. A drive mechanism is mounted to the housing and mechanically coupled to each lens assembly to move the lens assemblies longitudinally within the lens tube independently of one another. In doing so, the lens assemblies provide varying degrees of magnification between low or macroscopic magnification and microscopic magnification at the free end of the lens tube. A stage is also detachably secured over the lens tube and has a transparent window across its end adjacent the free end of the lens tube.