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25.726.  Jahresbericht  des  Deutschen  Hydrographischen  Instituts  1970/71

Draught  route  soundings.  The  four  charts  were  published  in  the  meantime  as
British  Admiralty  Chart  No.  5059  and  as  supplement  to  Vol.  I  of  the  German  Tide
Tables.  Detailed  predictions  for  10  new  places  of  reference  were  added  to  Vol.  II
of  the  Tide  Tables  (areas  other  than  European).
Since  January  1971,  the  tidal  observations  of  the  Scottish-English  coast  are  being
continuously  transmitted.  Thus,  motions  of  water  masses  penetrating  from  the
Atlantic  into  the  North  Sea,  in  addition  to  the  tides,  which  often  increase  or  decrease ­
  the  water  levels  in  the  German  Bight  by  as  much  as  0.5  m  can  be  traced
more  easily  and  taken  into  consideration  for  the  daily  water  level  predictions  or
storm  surge  warnings.
In  the  course  of  the  year  1971,  the  GHI  put  a  modern  high-speed  computer  H  632
of  Messrs.  Honeywell  into  operation  for  comprehensive  scientific  computations.
This  computer  has  magnetic  plates  as  external  storage.
The  Geomagnetic  Observatory  Wingst  was  responsible  for  the
correspondence  concerning  the  standardization  of  geomagnetic  base  values  of  14
European  observatories.  Within  the  framework  of  the  working  group  “Ionosphere“
of  the  German  geophysical  institutes,  the  observatory  continued  to  participate  in
the  prediction  of  the  quality  of  radio  communications.
At  the  General  Assembly  of  the  International  Astronomical  Union  in  Brighton  in
August  1970,  the  GHI  was  represented  in  three  commissions.  These  dealt  especially
with  the  question  of  reconciling  the  astronomical  definition  of  the  legal  time  with
the  new  atomic  definition  of  the  physical  unit  of  time  (second).  The  GHI  Time
Service  continuously  registered  the  time  difference  between  the  reading  of  its
caesium  beam  atomic  clock  and  the  pulse  phases  of  the  Loran-C-transmitter  at
Sylt  to  an  accuracy  of  0.1  l^s.  Such  measurements  are  employed  in  world-wide
intercomparisons  with  very  high  precision  of  atomic  clocks.  Besides,  numerous
mechanic  and  electronic  chronometers  of  ships  were  tested.
Apart  from  the  type  tests  provided  by  Law,  the  Hamburg  Department  and  the  nine
GHI  agencies  in  other  ports  tested  more  than  100  000  nautical  instruments  and
gave  expert  advice  for  the  installation  of  instruments.  From  nautical-technical
investigations  suggestions  were  gained  for  the  improvement  of  shipborne  nautical
instruments  and  devices.
Since  1  September  1970,  Germany  and  the  Netherlands  have  been  mutually  adopting ­
  their  Approval  Certificates  for  navigation  lights  (in  cases  of  retesting  only)  and
magnetic  compasses.  An  agreement  was  also  reached  with  Norway  for  the  full
mutual  adoption  of  Approval  Certificates  for  magnetic  compasses  from  1  November
1970.
The  new  text  of  the  approval  and  testing  conditions  for  navigation  lights  was  published ­
  in  the  “Bundesanzeiger"  in  connection  with  the  new  German  Regulations
for  Preventing  Collisions  on  the  German  Waterways  and  came  into  force  on  26  May
1971.  With  the  approval  of  the  Federal  Ministry  of  Transport  (BMV),  rules  for  appointing ­
  qualified  persons  as  GHI  assistants  were  issued  and  published  in  the
“Verkehrsblatt“  of  the  Ministry  of  Transport.