333 



These efforts to reach as close as possible to a natural representation 

 of the objects would quite have failed, as regards lantern slides, had I 

 not been seconded by the great skill and patience of Mr. George Smith 

 of the Sciopticon Co. ; for, after all, however good a negative may be, it is 

 not the goal, but only the means to the end, — the perfect positive. I found 

 that, particularly in the opaque and spot lens objects, no purely photo- 

 graphic positive process could do full justice to the delicate detail in the 

 negative, without sacrificing beauty and truth of result in the general repre- 

 sentation ; but in the perfection to which Mr. Smith has brought lantern 

 slides by the Woodbury type process, these difficulties have disappeared, and 

 the finest details are adequately represented, while the general beauty of 

 the result is enhanced by the rich colour and pure transparency of the pig- 

 ment employed by him. Mr. Smith has a half-dozen or so of landscapes 

 and other studies, which may be shown you after the micro slides have been 

 put through, and thus give you an idea of the excellence of the ordinary 

 lantern slide. A great feature special to the Woodbury process is, that 

 any number can be printed identical in excellence with each other ; this 

 again, is quite impossible by any purely photographic process. The follow- 

 ing is a complete list of the slides shown : — 



The diameters given are those of the magnification on the lantern slide. 



No. Diam. No. Diam. 



1. Foraminifera, grouped 



2. Foraminifera from Porto 

 Seguro 



3. Foraminifera from Porto 

 Seguro 



4. Foraminifera from Porto 

 Seguro 



5. Ditto from Connemara 



6. Ditto, Lagence 



7. Ditto, Operculum ... 



8. Ditto, Section of Nummulite 



9. Ditto, Quinqueloculina 



10. Ditto, Dentalina 



11. Ditto, Siliceous Casts 



12. Opliiocoma JZosula ... 



13. Kay of ditto 



14. Dental Apparatus of ditto... 



15. Dental plates of ditto 



16. Opliiocoma neglecta 



17. TJrasta rubens 



18. Polycistina, grouped 

 1 J. it )j 

 20. 

 21. 

 22. 



31 31. Coralline ; Acarmarchis 



27 fiabellata 



30 32. Bicellaria grandis ... 

 16 33. „ ciliata 



12 31. Head of Butterfly 



19 35. ,, Tipula 



10 36. Antenna Vapourer Moth ... 

 25 37. Synapta, Anchors and 



8 Plates 



38. Pinna Shell — Section 

 35 39. Eider Down 



28 40. Scales of Fern 



„ Ceratospyris ateuchus 62 41. Fairy Fly 



grouped 17 12. Cecidomyia ... 



42 43. Oaklapple Fly 



12 

 14 



20 

 10 

 11 

 10 



33 

 66 

 13 

 38 

 43 

 32 

 10 



