KEMAKKS BY SIR HERBERT JACKSON, K.B.E., F.R.S.* 



By the courtesy of the Chairman 1 was able to see in advance a 

 great number of the interesting papers which have been prepared 

 for this meeting to-day, and when I looked at them I discovered 

 that practically everything that I intended to say was included in 

 those papers. 1 have decided, therefore, that it would be better 

 for me to be brief, and deal very generally with perhaps only two 

 or three points. 



I take it that one of the chief reasons for this Symposium is to 

 consider methods for promoting the study of the microscope and 

 methods for extending its use in science, in industries, and in educa- 

 tion, I should like to mention first the position which we are in at 

 the present day with regard to one of the most vital parts of the 

 microscope, namely, the optical glass. I should like this meeting 

 to know that through the enterprise of British manufacturers we 

 have produced and we can produce optical glass in this country of 

 a quality equal at least to the very best that was ever obtained 

 from abroad. I should like also to say that I have had it from 

 the manufacturers themselves that they are perfectly prepared to 

 do their very best — and they have already shown that they can do it 

 — to produce any glass which may be called for. There is a great 

 deal yet to be done, not on their part so much, perhaps, as on the 

 part of those whose duty it is to make investigations with the object 

 of obtaining new glasses with optical constants differing from those 

 which have been made hitherto, so that combinations can be made 

 of even higher quality than those which we are familiar with in the 

 best lenses that exist. I think also that it should be well known 

 that, till o ugh the efforts of the Department of Scientific and Indus- 

 rial Research and in other ways, mathematical investigation on 

 methods of designing lenses are in progress, and I think we may 

 look definitely from these investigations for results which will make 

 a heavy demand again upon the skill and the enterprise of the manu- 

 facturers of optical instruments. 



I will not speak, as I had intended to do, on some comparisons 

 between the results of the work of British and foreign manufacturers, 

 except to say that it is certainly true that we have produced optical 

 trains in this country comparing favourably with any produced 

 anywhere else, but we do not always produce them with that constant 

 accuracy. I think it is fair to say that while, in the early history 

 of the microscope we took the initiative, in later years there has been 

 a tendency to follow rather than lead. At least, that is true of some 

 of the chief developments of the instrumental part of the micro- 

 scope. Now, what we have to do is no longer to copy, but to aim 

 at improvements by independent research and invention. There 

 exists at the present time, fostered by the Department which I have 

 just mentioned, an all-round spirit of research and enterprise. With 

 out elaborating the point, one can now express the hope that a 

 bright promise of future development will not fail of fulfilment 

 through lack of means on the one hand to attract the brains and 

 skill which are abundant in this country, and on the other hand to 



"••■■ See above, p. 43. 



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