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HISTORIC WRIST WATCH w.Radium Hands & Figures, OLMA / Switzerland (1930)

This is the stainless steel watch of my father, who was killed in  WWII.
I got it from my mother as I was 12 year old. I carried it day and night
until I was 30 and bought my  OMEGA AUTOMATIC  in Switzerland.

My job in Computer Science & Nuclear Medicine in the University Hospital
of Berlin allowed me to measure the RADIOACTIVITY of this watch ...

          18.5 nCi Radium-226  ( Half-Decay-Time = 1600 years )
   With its "Gamma Constant"  Γ = 0.825 [ ( R * m2 ) / ( h * Ci ) ]
   the EXPOSURE could be calculated:
          153 μR/h  on my WRIST   (=  1 cm distance )
     and  3.3 mR/a  on my GONADES (= 20 cm distance )

  ... Compare it with the "Natural Radioactivity" ~ 110 mR/a for Germany

H I S T O R I C A L   R E M A R K S :
Paul J. Bourquin was a skilled watch maker.  In 1860 he designed a watch
and named it  "Numa Jeannin"  after his son's name. In 1894 his son took
over the business and in 1906 he founded the factory NUMA JEANNIN CO. in
Fleurier / Switzerland  to produce  high quality watches under the brand
name  »OLMA«.  Since than,  OLMA  is on the market  for over  100 years.
Have a look at the OLMA HomePage ...

© C.HAMANN       06/27/11