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present, labour-intensive to such an extent that the system on the
whole is not particularly attractive.
In automatic mapping, based on tacheometric measurements,
better results have been achieved, although the correct automatic
drawing of the connecting lines between the mapped points causes
most difficulty.
The Dutch Cadastre has made ample trials with bearing and
distance measurements and on the automatic processing of field
readings. An extensive description of these trials can be found in
[98].
Apart from the Oxford System of Automatic Cartography al
ready mentioned in my last report, other methods have also been
developed, all aiming at the elimination of manual labour in map
making or revision to the greatest possible extent. In this connection
I am referring to data registration on a so called "creation sheet"
by means of a digitizing device (the "Pencil Follower"). The me
thods mentioned here can, at least for the time being, only be used
by the leading makers of topographic maps.
As regards the more common applications of automatic drawing,
I can refer to the favourable developments by the Office "des
Ponts et Chaussées" in France. In [99] P. Godin describes the
method they apply there, emphasizing the influence new methods
have on geodetic thinking. The application of automatic drawing
in mining is dealt with in [100].
The number of makes and models of automatic co-ordinatographs
and automatic drawing tables is gradually increasing. I would like
to give an impression of the equipment now in existence in this
field. The review is however in no way complete.
In [101] O. Weibel describes the electronically controlled co-
ordinatograph known as the Corograph of Contraves/Haag-Streit.
This instrument, controlled by the Cora computer made by the
same firm, combines a low speed of operation with high precision.
The instrument can draw both straight lines and curves as well as
letters, figures and other symbols. Input is by means of punched
cards or punched tape. Read-out is possible, showing the results
in written form, in punched cards or punched tape. In France, this
instrument, which is built there under licence by the firm of Labinal
in a somewhat altered model, is known under the name of "coor-
dinatographe Labinal". Its application by the Institut Géographi-
que National in Paris is described in [102]. Mentioned here, among
other things, is a highest attainable precision of 0.07 mm, and the
high cost of maintenance. The latter is a relative idea, and one
should not forget that people are generally inclined to use electronic
equipment more intensively than any other type of equipment.
An Italian-made instrument is the electronic drawing table
known as 03oM-Galileo. This electro-co-ordinatograph is primarily
intended as a plotting table for a photogrammetric restitution
instrument, but may in principle be used separately as well. The
