SEISMOLOGICAL REPORTS. 47 



SEISMOLOGICAL REPORT OF THE MELBOURNE OBSERVATORY. 

 Observatory, Melbourne, Victoria, 1st January, 1908. 

 The instrument employed at this observatory is a Milne hori- 

 zontal pendulum, constructed by the firm of R. W. Munro, London. 

 It is located in a dry and well-ventilated underground room in the 

 main building. It records photographically. The average period of 

 the boom ranges from 16 s. to 17s., the time scale is 60 mm. per hour, 

 and the angoilar value of an amplitude of 1 mm. on the records is 0'4". 



Tlie instrument has been kept in constant use throughout the 

 period from 1st January, 1907, to date, and has registered satis- 

 factorily. 



All seismograms have been measured, classified, and registered 

 in appropriate ledgers, and the results will be sent shortly to Pro- 

 fessor Milne for publication in the reports of the British Association, 

 according to a standing arrangement. 



Unfortunately, the last record of the year 1908 is that of the 

 disastrous Sicilian Earthquake of 28th December. 



P. Baracchi. 



SEISMOLOGICAL REPORT FROM ADELAIDE OBSERVATORY. 

 The Observatory, Adelaide, 30th November, 1908. 

 Dear Sir, — In reply to your letter of the 14th ultimo, asking 

 for an account of seismological work at the Adelaide Obsei-vatory 

 from Januaiy, 1907, to date, I send you herewith a list of reports 

 received from country stations during that period. 



A Milne horizontal pendulum seismograph has been mounted this 

 year at the observatory, in a building specially erected for the pur- 

 pose, but the fitting and furnishing of the seismograph-room and 

 developing-room have not yet been completed. It is hoped, however, 

 that this will be done by the end of the year, and work will then be 

 commenced with the instrument. 



The seismograph is of the latest pattern, and embodies several 

 improvements on its predecessors. It has been set up with the boom 

 in the meridian, the free end of the boom being to the north. 



Yours faithfully, 



G. F. DodwblpL, 

 Actino' Government Astronomer. 



