99 
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it appeared probable that the tablets pronounced to be spurious by 
Sir E. Maddpn were not Massmann’s, but two tablets on beech 
wood, forged by a dealer through whose hands Massmann’s tablets 
had passed. Mr. Kenrick records six instances of the discovery of 
Homan tablets in the Transylvanian mines. 
April 7.—Dr. Procter read a paper “ On Photolithograjdiy, 
Photozincography, and other methods of Heliographic Engraving.” 
The author stated that the tediousness and expense attendant on 
ordinary photographic printing, together with the uncertainty of its 
results owing to the frequent want of stability in pictures produced 
with silver-salts, rendered the discovery of some different means of 
multiplying photographic pictures highly desirable. He described 
the process adopted by Niepce de Saint-Victor for obtaining an 
etched metal plate, the pkotogalvanograpkic process of Pretsch, 
founded upon the discovery by Mr. Mungo Ponton (in 1830) of the 
photographic properties of bichromate of potash in contact with 
gelatine or other organic matters, and Mr. Talbot’s photoglyphy,— 
none of which processes had met with more than a limited success, 
the methods now chiefly employed being photolithography and 
photozincography. In these processes a positive picture is obtained 
from a negative photograph in transfer lithographic ink, and trans¬ 
ferred to a prepared lithographic stone or zinc plate ; this is then 
treated in the usual manner with gum and acid, and is ready to 
furnish impressions. Examples illustrative of the different stages 
in the process, and of its results, were exhibited to the members by 
Dr. Procter; these included some beautiful copies of prints presented 
by Sir Henry James, by whom the process of photozincography 
has been adopted with excellent results in the reduction of the 
Maps of the Ordnance Survey. 
A communication was also read from the Bev. Johx Kexrick with 
reference to some of the donations which had been made to the 
Society. Amongst these is a silver coin of Corinth, exhibiting on one 
side the head of Minerva, on the other the winged horse, Pegasus. 
A silver coin or medal of Charles II. (Carolus a Carolo) shows 
a figure of Britannia, with the motto, “ Quatuor Maria vindico,” 
—“ I claim the four seas,”—alluding to the famous dispute between 
the Dutch and English in the 17th century, with regard to the 
maritime supremacy of England. Of the copper tokens, foreign and 
colonial coins, presented by Mr. North, the largest number are 
