PROCEEDINGS 1841 — 1848. 
175 
" An elucidation of the geometical principles of Gothic architecture." 
A series of models illustrating some of the more intricate forms 
of geological stratification were exhibited by ^Ir. Thomas Sopwith, of 
Newcastle, and the same gentleman also exhibited several electrotype 
copies of fossils in the Museum of Economic Geology, then in Craig's 
Court, London, The thin deposit of copper which is formed on the 
wax or plaster cast from the original fossils conveys an exact idea of 
the minutest details of structure, and Mr. Sopwith pointed out that 
by these means correct copies of the best specimens of fossils could 
be multiplied to an indefinite extent, at a small expense, and every 
village museum might thus obtain electrotyped fossils, corresponding 
to those which adorn the cabinets of the Geological Society, or of 
the most careful amateurs. The electrot}']^)es were made by Mr. T. B. 
Jordan. Examples of medals and some ornamental objects were also 
exhibited, and the application of this new and interesting art was 
shown to be capable of embracnig a wide and useful range of objects. 
The most elaborate work of art could be copied as easily as a plain 
sheet. ''Engraved copper plates can be copied for eight shillings for 
each pound of copper, that is to say, four shillings for the matrix, 
and four shillings for the copy, as the first of these containing the 
lines in relief, is nearly as heavy as the second, or copy for engraving 
from. Thus a copper plate wliich has cost £100 to engTave, may be 
faithfully copied for as many shillings. The process is applicable to 
many elaborate forms of metallic vessels, and hence, we may conclude 
that it will, ere long, find its way into the workshops of our manu- 
facturers." It is interesting to consider the enormous use made of 
this process since the few examples, regarded as curiosities, were 
exhibited at the meeting in 1841, and how well conceived were the 
expectations of the author. 
Thomas Sopwith, M.A., F.R.S., was born at Newcastle-on-Tyne 
in January, 1803, and was a member of a firm of large cabinet and 
upholstery manufacturers. He gave considerable attention to mining 
and railway engineering, and attained some skill in these branches of 
knowledge. His reputation as a geologist was also great. He 
invented and constructed a number of large Geological ^Models of 
mining districts, now placed in the Museum of Practical Geolog}' in 
