RECENT PROGRESS IN GEODESY. 
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tober, 1864, there was effected an organization for the 
measurement of arcs in middle Europe. The first general 
report shows that nineteen States gave support to the project. 
The general plan remained unchanged until 1886, when the 
Middle European Association was merged into an interna¬ 
tional one and nations from all parts of the world became par¬ 
ties to the convention. The organization was continued for 
a period of ten years. In 1896 new powers were assumed by 
the organization, and a new convention, to hold for ten years, 
was drawn up. To this last convention the principal nations,- 
except England, have agreed, and have through diplomatic 
action become contracting parties to the agreement. This, in 
brief, is the origin and growth of the present organization. 
An outline of its methods of work and the results attained will 
show what is being done by concerted national action to deter¬ 
mine the size and shape of the earth. From the beginning of 
the work up to 1887 the results were largely of local impor¬ 
tance. Each State gave reports on the operations within its 
border and which were intended primarily to serve as the basis 
for a map of the country. The triangulation, measure of base 
lines, astronomical observations (such as latitude, longitude, 
and azimuth), precise levels, and tidal observations found 
their greatest use locally; but in the last ten years questions 
have been taken up which are of the greatest interest to each 
individual country and to the world as a whole, and so when 
investigation is made of the variation of latitude, the force of 
gravity, the aberration of light, deflections of the plumb line, 
etc., we are getting results from which all nations profit 
alike; and it is precisely these larger universal questions to 
which the International Association is now giving a large 
share of its attention. It is not worth while to pass in re¬ 
view at present the details of the work of the organization. 
Suffice to say that practically all the nations of Europe and 
some in America and Asia are devoting their best scientific 
energy to this line of thought, and the publications of the 
association are replete with reports of the greatest interest 
and value on studies of the external features of the planet on 
which we live. Passing over what has been done incident 
