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31./32. Jahresbericht des Deutschen Hydrographischen Instituts 1976/77 
house, similar stations on the lightvessel "Fehmarnbelt" and the research plat 
form "Nordsee" were taken into operation; they transmit continuous hydro- 
graphic data to the DHI direct. 
In the measurement field off Sylt, the investigations concerning the measure 
ment of waves were continued. On the basis of the extensive sea wave mea 
surements made during the JONSWAP*) Experiment, a numerical method of 
forecasting sea waves was jointly developed with scientists of other institutes, 
and this is being tested at the present time. 
In connection with the research work and the intended exploration and exploi 
tation on the German continental shelf, the DHI issued several permits or exten 
ded existing permits. 
The scientific services of the DHI, which are necessary for the safety of 
shipping (tide prediction and storm surge warning service; ice service; time 
and latitude service; geomagnetic service; as well as the testing of nautical 
instruments) were carried out as usual. As previously, Tide Tables and "Ge- 
zeitenkalender" (tidal calendar showing mainly times of high and low water), 
the Nautical Almanac, the Geomagnetic Yearbook, as well as Ice Reports and 
Ice Charts, were issued. The nautical publication "Der Seewart" and the "Deut 
sche Hydrographische Zeitschrift" were issued and each comprises six numbers 
per year. 
In order to obtain a deeper insight into the movement processes in the course 
of storm surges and to improve the forecasting of same, the DHI began — in 
1976 — to adapt hydrodynamical-numerical methods for the requirements of the 
storm surge warning service. In 1976, the time and latitude service began the 
preliminary preparations to transfer the photographic zenith telescope to the 
eastern outskirts of Hamburg, because the increasing intensity of light at night 
at its present location severely hinders the observations. 
About 30,000 type tests resp. individual permits, permissions to install, and 
tests carried out on board ship, for nautical equipment and instruments were 
undertaken. The initial and repeat testing of position lanterns for vessels coming 
within the jurisdiction of § 8a of the Seeschiffahrtsstrafien-Ordnung has been 
replaced by an assurance of quality on the part of the manufacturer and a 
repair and maintenance service carried out by recognized repair firms. The DHI 
has compiled Regulations for that purpose and issued them on 1 July 1976. On 
the other hand, with the coming into force of the International Regulations for 
the Prevention of Collisions at Sea 1972, on 15 July 1977, the 2nd Statutory 
Amendment Order to the Ship's Safety Regulations, and the revised text of the 
German Collision Regulations, the DHI was assigned further tasks: such as 
type-testing certification, and approval of the installation of sound signal- 
and manoeuvre signal equipment, as well as the recognition of repair firms for 
such installations and for navigation lanterns. The international co-operation in 
the field of testing was continued. 
Investigations and research work were necessary in order to test, amongst other 
things, the functioning efficiency of magnetic compass installations on board 
*) Joint North Sea Wave Project