48 ON POSSIBLE DISPLACEMENTS OE THE EARTH'S AXIS OE FIGURE. 



interior of the earth would cause the axis of figure to depart from 

 the axis of rotation ; and changes of form would result in order to 

 bring them again into coincidence. In this way there seemed to 

 be no limit to the change of position. 



Prof. Seeley pointed out that the supposed necessity for moving 

 the earth's axis of rotation depends upon palseontological considera- 

 tions, and inferences as to the conditions of existence of extinct 

 organisms, of the ways of life of which we are necessarily ignorant. 

 He cited the Musk Ox and other animals as still living in high 

 northern latitudes, and inferred that if food can be found for 

 animals so high in the scale of organization, it is reasonable to 

 believe that any of the lower animals might exist in those regions 

 under the present climatal conditions. It had been supposed that 

 the absence of light in the long arctic winter was unfavourable to 

 the existence of such plants as had been met with fossilized in 

 arctic latitudes ; but since Palms and other plants actually brought 

 from the tropics survive the winter in St. Petersburg, matted down 

 in absolute darkness for more than six months, it must be con- 

 cluded that high types of plant-life may become acclimatized to 

 conditions very different from those under which they at present 

 live ; and if plants in certain floras in the southern hemisphere are 

 regarded as showing any relation with Eocene plants of Europe 

 which indicates that the living forms are descended from the old 

 European stock, then those Eocene plants must have passed through 

 a great variety of climatal conditions without undergoing much 

 modification before they reached their present localities. Hence he 

 concluded that our knowledge is not at present sufficient to allow 

 us to dogmatize on such great questions. 



The Author said that so many questions had been asked that 

 even if he were able to answer them time would not permit. He 

 would only make two remarks. First. He had not attempted to 

 work out the subject in all its bearings, but to examine one view of 

 the case. The fact is that no question can be answered mathema- 

 tically unless put into a definite form. The object of such an in- 

 vestigation is to take a definite view of a given question, and to see 

 what comes of it. This is what he had endeavoured to do in the 

 present case. He was, of course, aware that there is great uncer- 

 tainty in the data of the question when regarded more broadly ; e. g. 

 the constitution of the interior of the earth is but very partially 

 known. In the second place, he ventured to think that one of his 

 results had an application to any way that might be taken of treat- 

 ing the question, viz. the proof that the amount of transferred 

 matter must be at the least a considerable fractional part of the 

 whole equatorial bulge, if a considerable change is to be effected in 

 the geographical position of the pole, and that even this large 

 quantity would have to be greatly increased unless it were moved 

 from a favourable position to a favourable position ; e. g. if matter is 

 transferred from one position to a neighbouring position, the quan- 

 tity might be very great and the effect but small. 



