TRANSACTIONS OF THE SECTIONS. 165 
the Crimean war gave birth to a small topographical and statistical department ; 
but only four years ago its staff consisted of but three officers, and even now it is 
hardly as large as one of the sections of its continental brethren. 
The progress of the European surveys, and especially of our own, has been marked 
by many results which have indirectly influenced the advancement of geographical 
science. Amongst these may be mentioned the improvements in instruments 
made during the progress of the Triangulation, the invention of the Drummond 
Light, of Colby’s compensation bars, &c., the connexion of the English and Con- 
tinental systems of triangulation, the pendulum observations at various places, 
the measurement of ares of the meridian, the comparison of the standards of 
lengths of foreign countries, of India, Australia, and the Cape of Good Hope, with 
our standard yard, which has recently been completed at the Ordnance Survey 
Office, Southampton, &c. In the same category may be placed the improvements 
in the art of map-engraving, in the application of chromo-lithography to the pro- 
duction of maps, as exemplified in the Dutch process of Col. Bessier and in the 
Belgian maps, and the employment of electrotyping to obtain duplicates of the 
original plates. By the latter process copies are taken of the engraved plates in 
different stages of their progress, and with different classes of information engraved 
on the different copies, which if mixed together would have confused them. Thus 
the one-inch map of England is published in outline with contours, with the hills com- 
plete but without contours, with the geology, &c. The art of photography has been 
largely employed in the production of maps, and its use is on the increase both in this 
country and on the continent, and especially in the Government Departments in India. 
The method of copying maps by photography without any error in scale or any distor- 
tion that can be detected by the most rigid examination was first proved to be prac- 
ticable and was adopted in the Ordnance Survey Department in 1854 by Major- 
General Sir Henry James, for the purpose of facilitating the publication of the Govern- 
ment maps of the United Kingdom on the various scales. Since that date the 
necessity of rapidly producing, multiplying, enlarging, and reducing maps has 
tended towards the development of the various photographic processes which have 
been brought to a high state of perfection, such as photozincography, photo- 
lithography, heliogravure, Col. Avet’s process used in Italy, papyrotype, &c. Some 
idea of the extent to which these processes are carried may be gathered from the 
fact that during the last five years photographic negatives on glass covering an area 
of 10,071 square feet were produced at the Ordnance Survey Office for map-making 
purposes alone, and from these negatives 21,760 square feet of silver prints were pre- 
pared and used in the various stages of the survey. An area of 959 square feet of 
the negatives was also used in producing 13,595 maps on various scales by the photo- 
zincographic process, which was also introduced by Major-Gen. Sir Henry James. 
It was by similar processes that the Germans were enabled to provide the enormous 
number of copies of the various sheets of the map of France required during the 
war of 1870-71. 
The topographical maps of European countries vary considerably in scale, the 
manner in which the ground is represented upon them, and the style of their execu- 
tion. Proposals have at times been made for the adoption of a common scale, but 
they have not hitherto met with much success; still, however, Sweden, Norway, 
Denmark, Prussia, Saxony, Switzerland, Italy, and Western Russia have each a 
map on a scale of oa and it is much to be regretted that Austria, when 
commencing a new map of the entire monarchy, did not adopt this scale instead of 
that of --559: On the flat surface of a sheet of paper all inequalities of the ground 
must be represented conventionally, either by hachures, by contours, or by a com- 
bination of both: each system has its advocates, and the maps of foreign countries 
present examples of all; but it may be remarked that the use of contours is becom- 
ing much more general than it was a few years ago. Any comparison of the maps 
of the various countries would necessarily occupy much time, so I will only add that 
as specimens of engraving the sheets of our one-inch map are unrivalled, and that no 
foreign maps can compare for accuracy of detail and beauty of execution with the 
sheets of our six-inch survey: Our great national survey is the most mathematically 
accurate in Europe; and it speaks much for the ability of the officers who have 
