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the affair of a few minutes, and a trifling expense, we should then possess forms and 

 markings which no labour of the engraver's tool could supply, even if time alone did 

 not at once offer an insurmountable difficulty. Forms obtained in perfection and 

 in high relief, in fact, the insects, as seen in the accompanying proofs, seem literally 

 to stand out from the flat surface of the paper: minute markings are clearly defined, 

 and although we lose colour, yet there is an approximation to it in many instances 

 which is very remarkable. I may call attention to the Alias and Strix major, and 

 also to the singular appearance of the green under the wings of Pontia Rapse, P. Napi 

 and P. Daplidice; in fact, the insects seem to possess in the plate a faint tinge of 

 green. But this art is more particularly serviceable when we wish to illustrate the 

 difficult forms we often meet with among the Coleoptera. Here it is of the highest value, 

 for whatever the eye can see. Photography will unerringly pourtray, and when once we 

 have a perfect drawing, with its lights, shades and halftones, the engraver (should his 

 assistance be required) will find his labours materially lessened, and a very large amount 

 of time saved. 



" Agaiu, to illustrate its easy applicability, I may mention that the accompanying 

 drawings, with the exception of the one of Ornithoptera, were prepared to be exhi- 

 bited at the late Meeting of the East Kent Natural History Society, which was held 

 on Tuesday, the 24th of November. I prepared my plates on Saturday, the 21st, and 

 printed and toned them on the following Monday ; therefore in the short space of two 

 days a series of drawings was finished which no art of the engraver can approach, 

 either for fidelity or beauty. Even this did not occupy two days ; the plates and prints 

 were only taken whilst the light was good. But to still more clearly illustrate the 

 advantage and rapidity of this method of copying specimens, I may mention that Mr. 

 W. W. Saunders kindly attended the late Meeting of our Society in Canterbury, and 

 communicated a paper on the Ornithoptera : the next morning he drove over to see me. 

 At half-past ten I took two plates of his beautiful box of Ornithoptera, a copy of which 

 is forwarded ; at a quarter past eleven he was obliged to leave to meet the train, on 

 his return home : thus in this short space of time we were enabled to obtain a photo- 

 graphic picture of a most beautiful and rare box of butterflies, and also to retain for 

 our Society a happy reminiscence of a most agreeable evening passed wilh one of the 

 late Presidents of the Entomological Society. 



" I now hope that sufficient has been said to point out how useful the photographic 

 art may be in connection with the study of several branches of Natural History, and 

 more particularly with that of Entomology. 



" The following apparatus is what 1 have used. Mr. Thomas Ross's new triplet 

 lens, well stopped down ; it covers a plate of ten inches by eight. The camera is by 

 Burfield and Eoach, expanding, and lined with black cotton velvet. The bromo-col- 

 lodion is by Mr. Linford, of Canterbury. This collodion works quickly, is very clean, 

 and is remarkably strong and tough. My developer is made as follows : — 



Sulphate of iron ... 2 drams 



Nitrate of potash . . . . 2 „ 1 scruple. 



Acetic acid . . . . 2^ „ 



Spirit of wine . . . . 5 „ 



Distilled water ... 10 ounces. 



I clean the plates wilh a solution of cyanide of potassium, the usual form. 



