Cold chamber for the working objects for microscopic and electron microscopic investigations

In combination, a microtome having a specimen arm, a knife, a base and a chamber for working the specimen at cryogenic temperatures mounted on said base, said chamber comprising:

• a compartment having a bottom and sidewalls providing space for working the specimens, said bottom and sidewalls being heat-conductive,
• an exterior jacket,
• an insulating liner separating said compartment from said jacket,
• a cover for said compartment, and
• a plural cryogen system, said system having a first cooling means containing a first liquid cryogen for cooling a first portion of said chamber, the first liquid cryogen having a first temperature, a second cooling means containing a second liquid cryogen for cooling a second portion of said chamber, the second liquid cryogen having a second temperature, said first temperature being lower than said second temperature, said first portion being proximate to the specimens and said second portion surrounding a substantial part of said first portion.