(key dates accor ding to the Gr egorian calender)

1610 30 September GEORG MARGGRAFE born in Liebstadt.

1626 Brother CHRISTIAN MARGGRAFE born in Liebstadt.

1627 April GEORG leaves his parental home and begins a tenyear period of travel and study throughout northern Europe.

— May Registration at Wittenberg University.

— November Registration at Strassbourg University.

1628 April Registration at Basel University.

1629-1633 Unregistered student in Ingolstadt, Altorf (near Nürnberg), Erfurt, and Leipzig.

1633 Return to Liebstadt for family visit.

1634 March In Wittenberg: obtained the degree of ‘Medical Candidate’ with an alchemical thesis written under direction of DANIEL SENNERT.

— Fall In Rostock, following lectures from the botanist SIMON PAULI.

1635 February/September In Stettin: observations of Jupiter with LORENZEICHSTÄDT.

1636 September Registration at Leiden University.

1637 January–Novemberm Regular observations at Leiden Observatory.

— November MARGGRAFE leaves Leiden for Amsterdam and Texel.

1638 January Departure from Texel to Brazil.

— March Arrival in Recife after a two months’ crossing of the Atlantic.

— 8 April [Trip 1] ‘Armada’ with JOHAN MAURITS and his troops (including MARGGRAFE) leaves Recife for São Salvador in Bahia.

— 15 May MARGGRAFE writes a letter in Portuguese to JOHAN MAURITS during siege of São Salvador in Bahia.

— 17-18 May Failed attack on São Salvador. Many casualties. MARGGRAFE almost killed by a canon ball.

— 5 June Returned in Recife.

— 25 June Failed observation of a lunar eclipse. The next day first letters to JACOB GOLIUS and FROM.

— July Baptism of ELISABETH SILNAER (1636-1639), daughter of HANS SILNAER, for whom MARGGRAFE constructs a horoscope.

— August MARGGRAFE receives a live boa constrictor. (Hist. Nat.

238).

— September First observational series in Recife without the

observatory.

— October [Trip 2] Letter from the island of Itamaracá to JACOB GOLIUS in Leiden.

Receives a large dead boa constrictor, which he buries, disinterring the skeleton three months later. (Hist. Nat. 238).

— 20 December Recife: succesful observation of a lunar eclipse with a 1-foot quadrant.

1639 February Description of a fish (Hist. Nat. 159).

— 18 May Letter in German to SAMUEL KECHEL in Leiden: ‘Ich habe alfür in Astronomie noch wenig observiren können, …’ Letter in Latin to FROM, from ‘nova civitade Mauricia est in Isla Anton Vaz’. Letter in French to JEAN and ANTOINE VAN HUYCK.