ON DETERMINATION OF GRAVITY AT SEA. 49 



was then in foreign parts, and Messrs. Holt, who accompanied him, 

 offered very kindly to mstaU a special chamber upon the dscataus im- 

 mediately upon her return to home waters, for the purpose of these 

 experiments. This generous offer was accepted and a cliamber built 

 which was capable of separate temperature regulation and htted with 

 certain necessary conveniences for the research. Lt is not proposed, in 

 the interim Keport, to describe this laboratory — that is reserved for 

 the main Eeport, which, it is hoped, will be completed shortly. 



In order to gain a first-hand knowledge of the method of using 

 Hecker's apparatus, it was decided that the Secretary should visit 

 Professor Hecker's laboratory in Strassburg as soon as the necessary 

 cahbration of thermometers and general overhauhng of the apparatus 

 had been accomplished. Unfortunately this took longer than was 

 expected, as four new thermometers had to be made, and Professor 

 Hecker was not able to wire that all was ready until three weeks before 

 the date of sailing. After five days with Professor Hecker the Secretary 

 returned to England, bringing with him the barometers and ther- 

 mometers and leaving five cases to be despatched direct to the Ascanius. 

 The glass parts were safely conveyed by hand to Beading, and subse- 

 quently to the ship in Liverpool. It was extremely unfortunate for 

 the success of the experiment that there was no time for assembhng 

 and testing the apparatus before the ship sailed. Although Messrs. Holt 

 placed their joiner and two carpenters at the continuous disposal of the 

 experimenter for three days before the ship sailed, and though Dr. 

 Sadler had come from Reading to assist in this work, it was not found 

 possible to get the apparatus installed and the final adjustments made 

 before the ship sailed. At first the variations in the temperature of the 

 special chamber afforded some trouble, but, thanks to the kind collabora- 

 tion of Captain Chrimes and the chief engineer, Mr. Douglas, it was 

 arranged with the refrigerating engineer, Mr. Latham, that the tempera- 

 ture of the chamber should be adjusted at intervals of about twenty 

 minutes during the day-time and one-hour intervals during the night. 

 The results of this frequent adjustment will be shown in the final Report. 

 It does credit to Mr. Latham's devoted attention. The Committee 

 records its appreciation of their services to the captain and engineers of 

 the Ascanius and to Messrs. Alfred Holt for having placed all then- 

 resources at the disposal of the experimenter. Unfortunately, Hecker's 

 apparatus did not prove satisfactory, because it was discovered late in 

 the voyage that all four barometers had developed leaks. It was hoped 

 at the time that these leaks had only developed during the rough 

 weather which preceded their discovery, but subsequent careful ex- 

 amination of the results has shown, unfortunately without any possible 

 doubt, that the barometers were never air-tight. This is perhaps not 

 very surprising considering that each barometer includes six metal to 

 metal joints, three glass to metal joints, and one glass tap, and that the 

 strains at sea are very considerable. After a consultation with some 

 of the members of the British Association on the Ascanius, it 

 was decided that the only hope of making successful use of Hecker's 

 apparatus was to coat each barometer with a heavy layer of wax. 

 During the comparatively calm weather which preceded the ship's 



1915. E 



