Freiburger historische Bestände - digital

resembled a miniature post-office pillar-box about 70 mm.
in height, from the top of which a gnomon or " index "
extended horizontally. There were other kinds of
" horologii viatorum" or travellers' dials, vulgarly
known as "compasses." They were combinations of a
horizontal string sundial with a compass. One of the
most ancient of these instruments may be seen in the
museum at Innsbruck. It is dated 1451, bears upon its
shield-shaped lid the German eagle, and was probably

mariner, especially as it would have enabled him likewise
to determine the variation of the compass-needle, and
even the latitude (by measuring the length of the
shadow cast by the gnomon), but I am not aware of its
ever having been introduced on ship-board in Behaim's
day. Magellan, many years afterwards, was content to
carry hour-glasses, similar to those which still survive
in many kitchens, where they regulate the time for boiling
an egg.2

A Horizontal String Sundial, 1451.

A Universal Equinoctial Sundial adjusted to Lat. 36° S.

made for the Emperor Frederick III.1 A similar dial,
dated 1453, from the Spitzer Collection, is now in the
British Museum. The arms of Habsburg are engraved
upon its shield, and with the exception of the style of
ornamentation both instruments are alike. The dial-plane
measures 78 by 59 mm. and holds a compass. On
lifting the shield-shaped lid, a string, serving as gnomon,
is drawn up. Usually, however, these string dials were
made in the shape of a square box, as described in the
1 Cosmographicus Liber' of P. Apianus (Landshut,
1528).

But whilst horizontal dials or " compasses" served
only in the latitude for which they were made, an equinoctial
dial, that is, one whose dial-plane is parallel to the
equinoctial plane with a stylus or gnomon rising perpendicularly
from its centre, could easily be converted into a
universal dial, adjustable to any latitude. The manner
in which this was done is shown in our illustration. Such
an instrument might have proved of real service to the

1 For a full description of this and of other ancient sundials, see
A. Wolkenhauer,' Mitt. d. geogr. Ges. in Miinchen,' I., 1905, p. 251. These
compasses were no doubt made at Vienna, where Purbach wrote his
' Compositio compassi cum regula ad omnia ^limata.' At Nuremberg the
compass-makers were incorporated in 1510, but Dr. Mummenhof, on
searching the ' Biirgerbuch,' discovered the names of two masters of the
craft in the list of citizens for 1481. But Regiomontanus, the pupil of
Purbach, is known to have made sundials years before at Nuremberg
(H. Wagner, ' Nachr. d. K. Ges. der Wiss. zu Gottingen,' philosoph. hist.
Klasse, 1901, Heft. 2).

Of course, it is quite possible that Martin Behaim
imported into Portugal portable sundials, small metal
astrolabes and other instruments for which his native
town was famous, just as his brother Wolf, about ten
years afterwards, imported " Nuremberg eggs " or portable
wheel watches, which had only recently been invented.3

The Ephemerides.

Martin Behaim has been credited not only with having
introduced into Portugal certain astronomical instruments,
but also with having made known there the ' Ephemerides
' of Johann Midler of Konigsberg, known as Regiomontanus
. These famous ' Ephemerides ab anno 1475
ad annua 1506' were published at Nuremberg ten years
before Behaim came to Portugal, and were reprinted at
Venice in 1483. Is it likely that King John, who took
such a lively interest in scientific pursuits, and his advisers,
should have remained ignorant of the existence of a work
of such importance? But even supposing that these
« Ephemerides ' had first become known in Portugal

2 P. Nunes (' Opera,' Bas. 1., p. 123) says that sundials were rare on
board ship.

3 Schlagurlein—striking watches^are mentioned among the articles
left behind by Wolf when he died in 1507. They were to have been sold,
but up to 1518 no money realised by the sale had been received (Letter
of Michael Behaim to Jorg Pock, Ghillany, p. 112). These famous wheel-
watches were invented early in the sixteenth century at Nuremberg by
Peter Hele of Strassburg (d. 1540).