2IO CARNEGIE INSTITUTION 



instructions, and the observations already collected, to second the 

 realization of your project. It is gratified that its efforts have been 

 appreciated and would be happy to see one of its members officially 

 associated with the organization of this important international 

 undertaking. 



Paris, March 2^, igo2. 



\Professor A. Schtcster, Director of Physical Laboratory, Owens Col- 

 lege, Matichester, to the Carnegie Institution^ 



I have seen a proposed scheme for an international magnetic 

 bureau, on which I should like to make the following observations : 



I believe that no material progress of terrestrial magnetism is 

 possible until our knowledge of the magnetic constants of the great 

 ocean basins, especially the Pacific, have been determined more 

 accurately than they are at present. There is reason to believe that 

 these constants may be affected by considerable systematic errors. 

 It is possible that these errors have crept in by paying too much 

 attention to measurements made on islands and along the sea coast. 

 What is wanted is more numerous and more accurate observations 

 on the sea itself. I have had occasion recently to consider this 

 matter very carefully, and I have come to the conclusion that the 

 observations that are going to be made in the Arctic and Antarctic 

 regions will be of very little use to us until we can supplement them 

 by measurement in other portions of the ocean. It would be most 

 useful, to my mind, to make a complete survey round the world of 

 two circles of latitude, one in the northern and one in the southern 

 hemisphere, say 50° N. and 40° S. of two circles of longitude, say 

 150° E and 100° W., taking them as far north and south as can be 

 done without much trouble. As regards reduction of observations, 

 there can also be no doubt that private enterprise is no longer capable 

 of dealing with it. Anybody who has not a staff of computers at 

 his disposal is at present incapable of working out any ideas he may 

 have. 



The problems which might be worked out are all of very consider- 

 able scientific importance. Whether they are also of practical im- 

 portance is not possible to affirm, but such practical utility is by no 

 means excluded. The other investigations mentioned in the scheme 

 are also of importance. 



Manchester, Ja^nmry 26, igo2. 



