Annual Report. 297 



body as the British Association for the Advancement of Science, 

 would probably meet with attention from navigators, and lead 

 to valuable results. 



It is a common opinion that the state of the weather is in- 

 fluenced by the position of the sun and moon in respect to 

 the earth, and it cannot be doubted, that in regard to this 

 climate the opinion is well founded. We are in the position 

 where a cause acting generally, though not strongly, is most 

 likely to bring its effects to notice. It cannot be doubted 

 that there is at least a half- monthly tide in the atmosphere 

 corresponding to the springs in the oceans, and any hesitation 

 or activity which these accumulations produce in the great 

 currents will be most felt at their boundaries ; besides, though 

 the action of the moon may not, as has been calculated, avail 

 to produce a movement of more tlian a few miles per day in 

 the atmosphere, this may, by the translation of their boundaries 

 and intermingling of currents, produce a total change of 

 weather in the neighbourhood of these limits. If, moreover, 

 this lunar influence should, as may be conceived, exert its 

 action in a direction vertical to, or inclined to, the surface of 

 the earth any where, then a movement of a few miles would 



f (reduce an inevitable change, for above the summer of every 

 and there lies in the upper regions of its atmosphere all the 

 rigours of a polar winter. It would be of general importance 

 then, and save the trouble of an interesting reference, if meteor- 

 ological diaries followed the periods of lunations or noted the 

 ase or day of the moon, and also the difference betv/ixt her 

 declination and that of the sun. 



5. In regard to GiioGRAPHv : 



We had to remark at last Anniversary, the origin in this 

 Association of an enterprise which has excited the highest pub- 

 lic interest, and promises very extended advantage. The 

 Central Expedition has now started under Instructions, a copy 

 of which lies on the table. It will be seen from them, 

 that it is proposed to explore minutely the ^rcat square space 

 which forms a tantalizing blank on onr maps, immediately 

 north of the Gariep, and extending to the regions now or 

 formerly bearing commercial relations with (he Portuguese co- 

 lonies. On this region there obviously rises a sort of ridge or 

 spine which separates the waters falling to the two seas. The 

 descent on the western side, which is chiefly to occupy the at- 

 tention of the expedition, must be very gradual, but whether it 

 elopes regularly or proceeds on a level to descend rapidly near 

 the western shore, remains to he determined. In either case 

 liowcvcr, the climate and temperature of the district to be 

 traversed by the expedition must, when compared with the 

 regions on the coasts, be dry and cooU It is to be feared, that 



rp 



