14 



Fi^ 16, In Alveopora we have the lis^htest of aU 

 the stony corals. The walls are s > pierced all 

 round with holes as to resemble a lattice work 

 rather than plates of cirbonate of lime, 



Fi^s. 17 and 18, Ajiricia, aad Fig. 19, Cophoseris, 

 with its fern-like crest-;, b^lon^ to the family 

 Lophoseridx, as also Fig. 6. 



Figs. 20 and 21, Miissa, like some other orals, 

 multiplies from a single cup. -VTr. S-iville Kent 

 states that the polyps of this genus do not exptad 

 their tentacles in daylight. 



Fig. 23, Astrea, of the family Astrseidse. Some 

 of these corals are found in blocks of great size. 



Mr. W. Saville Kent, who has studied coral 

 reefs perhaps more closely than anyone else, and 



whose baautiful b >ok on the Great Barrier R-^ef of 

 A-Ustrili^ 15 oa-iof the m nfc wjad-jrful ppoinjtioas 

 on coral life thi.t has ever appeared, has very kindly 

 sent us two plate.^ fur reproduction in our piges. 

 These views, tikea with greitcire aad skill, con- 

 stitute a revelation to the ordiaary mtnd as to the 

 real conditious of coral growth. The views are 

 from Mr. Saville K-^nt's most recent b>ok, " A 

 Naturalist in Australia." We regret we are 

 unable to reproduce them in the lovely colours of 

 nature. We must refer our readers to Mr. K-^nt's 

 books if they are interested in the subject of coral 

 reefs, for in them are miay beautiful photographs 

 and descriptions of fasoiQiting sijoae^i th it vve can 

 hardly imagine. 



FOURTH WINTER MEETING, 



TUESDAY, NOVEMBER 20th, 11)00. 



PHOTOGRAPHY MADE EASY."— LECTURE BY MR. SANDELL. 



The fourth winter meeting of East Kent Natural 

 History Society and the Photographic Society was 

 held in the Reference Library uf the Beauey Insti- 

 tute on Tuesday evening, November 20. There was a 

 large audience, who listened with deep attention to 

 a lecture by Mr. J. T. Sandell, M.P.S., of London, 

 on " Photography mide easy " by moans of double 

 coited platds and films Capt. J. Gordon McDakin 

 presided, aad there were also present Miss Cole, 

 CouDcillor J. F. Whichcord, Misses Mason (2), 

 Councillor Wright Hunt. Mdssrs. W. H.. Fielding. 

 P. Finn, J. Kay, G. P. Argrave, W. G. Austin, J. 

 T. Smith, .lohnson, Fiddian. Mocbridge, W. .Surrey, 

 F. Snell, Buckley, A.. Lander {Hon. Secretary), etc. 



The Chairman, in opening the meeting, referred 

 to the pleasure it gave him to be present, especi- 

 ally at a photographic mneting, and said he did 

 not look upon photography simply as a servant of 

 science, but in itself an art and a science which 

 was well worthy of study and practice. He 

 expressed regret at the absence of the President 

 (Councillor Horsleyj who was again very unwell. 



The Secretary having read letters of apology 

 for non-attendance from the President, Mr. Sidney 

 Harvey, Miss Holmes, and Miss Phillpjtts, he pro- 

 posed the following lady aad gentlemen as members 

 ->f the Society :— Dr. S^voru, Miss Sworn, Mr. 

 Hamilton, and Mr. Sage, of Bifrons. 



Councillor Whichcord seconded, and it was 

 agreed. 



The Photographic Secretary, Mr. J. Kay, then 

 read his report on the develojjing competition, 

 which stated that some very good results had been 

 obtained, the prize being awarded to Mr. C. Buck- 

 ingham. 



Mr. Sandell then delivered his lecture. He said 

 he was asked to describe the why and wherefore 



of the Cristoid double plates, with which he was 

 identified and which increased the facility with 

 which photography might be practised. To do 

 this it would be necessary to go into the theory of 

 photography rather more deeply than they would 

 care to bo troubled with, and so he would confine 

 him::eif more particularly to the mechanical ait. 

 The primary difficulty met with in photography 

 was in the exposure. An amateur was quite at 

 sea at first as to what exposure he should give, 

 and the general result was that for <;ome 

 considerable period his work was a series 

 of failures, in all probability from gross 

 over-exposure. It occurred to him that this over- 

 exposure could be overcome by means of the 

 device of placing a second film at the back of the 

 more sensitive film. The light passing through 

 the upper film was modified on the less sensitive 

 film, so that if the upper film was over-exposed 

 they would have a correct exposure on the lower 

 one. The film consisted of the Double Emulsion 

 film of the Sandell '' perfect " plate, etch layer 

 being coated more thickly than in the plate. The 

 combination was thus independent of any base 

 whil^itwas 2 -j times lighter than glass plates. 

 He experimented with this and thy results were 

 perfectly successful. But they could scarcely do 

 away with one difficulty in photography without 

 introducing other, and there were at first some 

 slight difficulties in working the plates. Here 

 many workers failed. They failed to see that 

 where they had to develop an image so d-'eply set 

 in the film the development must be a parfect 

 one. They found they had given an over-espjsure 

 and the picture coming out fogged, they gave it 

 up. But with the double films, to over-expose both, 

 it would be necessary to give a much longer 



