628 bepoet — 1878. 



FRIDAY, AUGUST 16, 1878. 



The following Papers were read : — 



1. Notes on some Geographical Variations on the Coast of France. 

 By J. S. Phene , LL.D., F.8.A. 



Dr. Phene, having for years past taken careful observations and soundings in 

 the Morbihan sea, was of opinion that a very large portion of what was now that 

 inland sea did not exist, in fact nothing that could be so called had existed, in the 

 time of Cffisar. The lie de Batz, an island near the mouth of the Loire, cele- 

 brated for strange and ancient rites, mentioned by classical writers, was now a 

 promontory, and the former littoral line only to be traced with difficulty. Dr. 

 Phen<5 believed that he had discovered the island of Avalon, the reputed place of 

 King Arthur's burial, though from the island having been severed into two by the 

 sea, and the name retained only by the smaller portion, it had been overlooked, 

 and even in the neighbourhood no one knew of it but local fishermen. A dolmen 

 unlike any other in France or Britain on the larger portion, and the traditions of 

 the locality, seemed to put the matter out of doubt. 



2. On Processes of Map-producing. By Captain J. Wateehouse, B.S.C., 

 Assistant Surveyor-General of India. 



Before the introduction of lithography, about the beginning of the present 

 century, the only means by which maps could be reproduced was by engraving on 

 metal plates or on wood, both tedious and expensive methods. With the invention 

 of lithography, a new impetus was given to cartography. The new art was, how- 

 ever, scarcely out of its cradle when Joseph Nicephore Niepce, of Chalons-sur-Saone, 

 experimenting unsuccessfully in endeavouring to find a substitute for lithographic 

 stone,, conceived the happy idea of obtaining images on metal plates by the sole 

 agency of light upon thin films of asphaltum or bitumen of Judsea. 



Since these first essays of Niepce, the idea of superseding the slow and laborious 

 hand-work of the lithographic draughtsman and engraver by the quicker, cheaper, 

 and more accurate processes of photography has been steadily kept in view. 



The first serious attempt to carry out the method practically appears to have 

 been made by Sir Henry James, RE., in 1855. The result proved the great value 

 of photography for the reproduction of maps, and the enormous saving in time and 

 money that could be effected by its use. In 1860, Captain A. de Courcy Scott, R.E., 

 perfected the process of photozincography, which has since been employed with so 

 much success and advantage at the Ordnance Survey Office, Southampton, and the 

 India Survey Offices in Calcutta, Dehra Diin, Piina, and Madras. 



By a curious coincidence, at the very time when this process was being worked 

 out in England, Mr. W. Osborne, of Melbourne, Australia, independently perfected 

 an almost identically similar process of photolithography, which has been exten- 

 sively used for reproducing the maps of the Australian Colonies. 



Little progress was made in the practical working of photolithography or 

 photozincography in India till 1865, when Mr. J. B. N. Hennessey, of the Great 

 Trigonometrical Survey, fairly established the process at Dehra Diin. 



The specific advantages to be gained by the use of photography for the repro- 

 duction of maps are — 



