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Examination Check List

This list is a guide to be used in the centennial examinations of Capsule No. 2. A cumulative record of test results should be made and a copy stored in Compartment No. 29 of the capsule.


1:1 Deterioration of metal alloys
The metal alloy used for the body is an austenitic stainless steel resistant to the separation of alpha phase ferrites. However, any changes in physical and chemical properties – especially at weld joints – should be determined by radiographic examination, electron beam microscopic analysis or other suitable method.
1:2 Corrosion
Areas subject to stress corrosion (legs, handles, weld joints, etc.) should be thoroughly inspected.
1:3 Inner compartments
Ceramic wool (aluminosilicate) cushioning was used between the compartments and the body wall. This material should be inspected for changes caused by reaction with the steel alloy.


2:1 Purity
Has there been any leakage of the argon gas used to fill the capsule? Analyze the gas to determine whether there has been any contamination.
2:2 Contamination
If other gases are discovered, determine the cause.


3:1 Condition of special containers
Determine any changes in chemical or physical properties that might have been caused by humidity and/or gaseous decomposition.
3:2 Internal atmosphere
Special items were sealed in conditions of relative humidity of about 5% or about 30%. Has there been any change in humidity levels?
What is the extent of gaseous decomposition, if any?
If, after careful analysis, abnormalities are discovered, the probable cause or causes should be determined.
3:3 Physical changes in contents
o what extent has decomposition, if any, progressed?
Has this decomposition reached a state of saturation?


4:1 Tape recordings
Determine any changes in sound quality, signal-to-noise ratio, magnetic induction between tape layers, etc., and any changes in the physical properties of the tape.
4:2 Phonograph records
Assess the quality of reproduction. Is there any physical distortion or warping of the record?
If corrosion exists, is it of a progressive nature?
4:3 Film and photographs
Does the gelatin film or photographic printing paper show evidence of physical change or chemical decomposition? This should be determined microscopically. Is there any change in the quality of projected images? In motion picture film, is there any change in the noise level of sound reproduction?
4:4 Functioning of components
Many semiconductor elements and electronic components are inherently subject to change with time. Their nature requires a quasi-stable state in order to produce the characteristics required by the equipment in which they are used. Determining the extent of such change should be interesting from academic and engineering viewpoints.
4:5 Devices
Miniature radio, television set and tape recorder : These also, for the reasons given in 4:4, are subject to change due to the nature of the materials used in their construction. Determine overall performance characteristics.


5:1 Paper, fibres and plastics
  1. a) In addition to individual samples of various fibres, papers and plastics, the capsule also contains finished products having combinations of these materials in their construction. Determine the following:
    Changes in colour
    Changes in physical strength
    Compare any differences in changes discovered in items made of a single material and items in which the material is used in combination with others
  2. b) Special examination : The average degree of polymerization of paper fibres in printed matter contained in the capsule is between 400 and 500. Has this average changed? And to what degree?
5:2 Changes in colour
Lithographed works, colour gravure, the picture scroll "Japanese Manners and Customs": To what extent have the colours changed?
Which dyes or pigments were responsible for this change?
Was the binder responsible?


6:1 Bacterial growth
Miscellaneous phages and bacteria may have been produced by unforeseen circumstances. If so, what has been produced?
Conduct bacteria cultivation tests on items where this possibility exists, i.e. paper, textiles and food products.
6:2 Germ-free cultivation
Stored phage and bacteria : What effect did freeze-drying and storage at a constant temperature of 17ºC have on the life of the bacteria?
Bacteria should be cultivated in a sterile atmosphere to determine whether life still exists. If any degree of life exists, the bacteria may be recultivated, freeze-dried and re-stored.
6:3 Test plantings of seeds
Determine the effect of storage in conditions of relative humidity of 5% and temperature of 17ºC by test plantings. Are these conditions appropriate for preservattion purposes?


7:1 Changes in subterranean temperature
Note and record maximum-minimum indications for the period prior to unearthing. The indication must have been read while the thermometer was in its original underground position.
7:2 Plutonium timekeeper
Has the clock moved exactly one full dial gradation for each period of 100 years?
Has there been any leakage of gas?
Has there been any radiation leakage or radiation damage?


8:1 Condition of the site
Stainless steel capsule container, concrete capsule enclosure and steel tube soil pile: These should be renewed each time the capsule is re-buried. It is important, however, to examine and record the condition in which they are found when the capsule is unearthed.


  1. The checkpoints listed are suggested minimum requirements for observation and examination of the capsule, its container, enclosure, site and contents.
  2. Subjects l, 2, 3, 4:2, 5:1 and 7:1 are considered to be definite requirements; the other items should be highly interesting from academic and scientific standpoints.
  3. The tests in Subject 6 should be particularly significant when the capsule is opened for the first time in the year 2000 AD.

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The contents of this site are excerpted from THE OFFICIAL RECORD OF TIME CAPSULE EXPO'70(March 1975). Please note that company and organization names may differ from those of the current ones.

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