Drawing, Les Mesures
Attributed to the school of Frans Floris.
By kind permission of the Ecole nationale sup�rieure des Beaux-Arts, Paris.
Figure 17
Geographical Globe
From Peter Apian and Gemma Frisius, Cosmographia, sive descriptio universi orbis (Antwerp, 1584)
(catalogue no. 2).
Note the quadrant, the pillar sundial, and tiny dipych sundial indicating the meridian.
Figure 18
The square used to illustrate one of the properties of a semicircle.
From Adriaan Metius, Arithmetic� et geometri� practica (1611).
Figure 19
The use of the geometrical quadrant.
From Adriaan Metius, Arithmetic� libri duo: et geometri� libri VI (Leiden, 1640).
The linear division of the sides of the square means that the angles required are taken as ratios instead of in degrees; this allows the convenient conversion of, for example, lengths measured on the ground to inaccessible heights.
Figure 20
Introductory page to the second section of Blaeu's book, 'according to the true hypothesis of the world of N. Copernicus, which proposes the motion of the earth'.
Coignet's sector is described in the manuscript illustrated in figure 7 and figure 8 and is used to perform calculations relating to volumes of wine in barrels.
Michel Connette [Coignet], La g�ometrie (Paris, 1626).
Figure 27
Gauging a barrel.
From Adriaan Metius, Arithmetic� libri duo: et geometri� libri VI (Leiden, 1640).
The same woodcut appears in his Arithmetic� et geometri� practica (1611).
Figure 28
The use of the shadow square or geometrical quadrant on an astrolabe, simple theodolite or Holland circle.
The shadow square is used to take bearings from either end of a measured baseline MN, and then to transfer these measurements on to a plan drawn to scale (see figure 30). Gemma Frisius, De astrolabo catholico (Antwerp, 1556)
(catalogue no. 3).
Figure 30
The use of the shadow square or geometrical quadrant on an astrolabe, simple theodolite or Holland circle.
Bearings taken with the shadow square (see figure 29) after transfer on to a plan drawn to scale. Gemma Frisius, De astrolabo catholico (Antwerp, 1556)
(catalogue no. 3).
Figure 31
Figure 17
Figure 18
Figure 19
Figure 20
Figure 21
Figure 22
Figure 23
Figure 24
Figure 25
Figure 26
Figure 27
Figure 28
Figure 29
Figure 30
Figure 31