4 PRESIDENT S ADDRESS. 



by machine with the monotony of a knife grinder, they have seen 

 the far-off end, the imperial issues to which all their labour 

 tended. End and issues which would never be reached unless the 

 divisions on a scale were accurately gauged, or the dots on a 

 photograph surely indexed. 



These things have to be done. They are part of the price 

 we have to pay for our results. And let us be thankful that 

 results, like gold and diamond, have to be mined for by the toil 

 of our fingers and the sweat of our souls. 



The other day I was again reading through the classical 

 volumes on the solar parallax, by Gill. They form Vols. \'"I and 

 \^II of the Cape Annals, two bulky tomes running to over a 

 thousand pages, mostly packed with figures. These volumes 

 represent the labour of ten years : they are the condensed sum- 

 mary of computations that, if stacked in a pile, would re^ch the 

 height of thirty feet". And all to settle the second decimal place 

 in an astronomical constant ? Nay ! but to su])ply with all avail- 

 able accuracy a base line with which to measure the universe ! 



In the correspondence between Sir David Gill and Dr. 

 Kapteyn. concerning the proposal of the latter to measure all the 

 photographs taken at the Cape, and so form a photographic 

 Durclimusterung of southern stars, the following pregnant 

 remark occurs. Kapteyn is writing to Gill. 



" I have talked the matter of the Photographic Durchmusterung over 

 with Dr. Bakhuyzen and his brother. I am bound to say that they were not 

 very enthusiastic about the matter ; of course, they thought the results once 

 reached of immense value, but the drudgery to be gone through before these 

 results are once got into the form of a catalogue almost unbearable. 

 However, I think my enthusiasm for the matter will be equal to six or seven 

 years of work." 



This was in December, 1885. 



In 1899, Kapteyn wrote: 



"The Cap3 Photographic Durchmusterung may at last be considered 

 complete. The work has cost nearly double the time, the six or seven years' 

 which I originally estimated would be required." 



Of this magnificent sidereal survey more anon ; it is of the 

 present, to point out that its completion meant fourteen years of 

 unremitting labour, and the examination, again and again, for 

 position and brightness, of nearly half a million stars. 



I mention these two supreme labours here (labour charac- 

 teristic of all scientific research) lest by passing on simply, as T 

 shall, to the results achieved, it be forgotten by what strenuous 

 service, by what arduous toiling these results have been attained. 



It is the mind to work, and the capacity to toil, that makes 

 the difference between the true scientist and the one who is simply 

 interested in science — and no more. 



A chronicle of pioneer work in Astronomy makes good read- 

 ing for those who delight in South African achievement. It is 



