In the early seventeenth century the family left Amsterdam, going to Antwerp in the Spanish Netherlands. Here in the year 1609, according to an Antwerp record, Arnold constructed a “Sphaera Mundi,” which he dedicated to the chief magistrate of that city, receiving therefor 120 Artois livres. It probably was not long after this date that he was appointed Globe Maker of the Archdukes, a title he retained until the death of the Archduke Albert in the year 1621, and a somewhat later record tells us that he was honored shortly after that event by an appointment to the office of Royal Cosmographer and Pensioner of His Majesty the Catholic King. Michael became a resident of Brussels, where he carried on his work as an engraver, particularly of maps, but it was as an astronomer that he won special distinction, having given much attention to the investigations of methods for the determination of longitude and he is further credited with having given the so-called seas of the moon the names by which they are still known. As globe maker perhaps the greater honor is due Jacobus Florentius, since it appears that Arnold, though perhaps the more active, reproduced in the main only the works of his father, adding improvement here and there and endeavoring, perhaps in part for business reasons, to keep his globe maps up to date. Reference has been made above to the oldest extant Van Langren globe, which bears the date 1585. Van der Aa refers to a request of Arnold Floris van Langelaer and of his father, Jacob Floris van Langelaer, presented to the States of Gelderland and accompanying a copy of his globe, which seems to have been dated 1580. Of this globe it is stated that it was “een seer correcte ende schoone Globum terrestrem, van de grootste forme,” and that it was inscribed as is that of the year 1585. A doubt, however, arises as to the accuracy of the date 1580, since Van der Aa states in the same article that Arnoldus was born in the year 1571. This particular globe was formerly kept in the “Geldersch Gerichtshof,” as Van Hasselt tells us, but since the destruction of that court nothing has been known of the inventory of the objects which had been placed therein. In support, however, of an early date, perhaps 1580, for the first Van Langren globe, we find in the dedication of a work by Nicolas Petri, published in the year 1588, and issued as a manual for the use of globes, that it was especially made for the use of a Van Langren globe. In this work the author is represented in picture in the act of examining a globe, a picture practically the same as that appearing in a work by Petri issued in the year 1583. It seems, therefore, not to be an erroneous inference that the author gives us here a representation of the Van Langren globe of 1580, which is wanting much in the accuracy with which its details are given.