5. To sound and marke the Depths of Coasts and Ports, and such other places nere the shoar, as they shall think fit. 6. To take notice of the Nature of the Ground at the bottom of the Sea, in all Soundings, whether it be Clay, Sand, Rock, &c. 7. To keep a Register of all changes of Wind and Weather at all houres, by night and by day, shewing the point the Wind blows from, whether strong or weak: The Rains, Hail, Snow and the like, the precise times of their beginnings and continuance, especiall _Hurricans_ and _Spouts_; but above all to take exact care to observe the _Trade-Winds_, about what degree of _Latitude_ and _Longitude_ they first begin, _where_ and _when_ they cease, or change, or grow stronger or weaker, and how much; as near and exact as may be. 8. To observe and record all Extraordinary _Meteors_, Lightnings, Thunders, _Ignes fatui_, Comets, &c. marking still the places and times of their appearing, continuance. &c. 9. To carry with them good Scales, and Glasse-Violls of a pint or so, with very narrow mouths, which are to be fill'd with Sea-water in different degrees of _Latitude_, as often as {143} they please, and the weight of the Vial full of water taken exactly at every time, and recorded, marking withall the degree of _Latitude_, and the day of the Month: And that as well of water near the Top; as at a greater Depth. * * * * * _Some Observations concerning _Jupiter_. Of the shadow of one of his _Satellites_ seen, by a Telescope passing over the Body of _Jupiter_._ I have received an Account from very good hands, That on the 26^{th.} of _September_ last, at half hour after seven of the Clock, was seen, both in _Holland_ and in _France_ (by curious Observers, with very good Telescopes) the shadow of one of the _Satellites_ of _Jupiter_, passing over his Body. One of those small Stars moving about his Body (which are therefore called his _Satellites_) coming between the Sun and it, made a small Eclipse, appearing in the Face of _Jupiter_ as a little round black Spot. The Particulars of those Observations, when they shall come to our Hands, we may (if need be) make them publik: Which Observations, as they are in themselves very remarkable, and argue the Excellency of the Glasses by which they were discovered; So are we, in part, beholding to Monsieur _Cassini_ for them, who giving notice before hand of such Appearances to be expected, gave occasion to those Curious Observers to look for them. * * * * * _Of a permanent Spot in _Jupiter_: by which is manifested the conversion of _Jupiter_ about his own Axis._ Besides that Transient Shadow last mentioned, there hath been observed, by Monsieur _Cassini_, a permanent Spot in the Disque of _Jupiter_; by the help whereof, he hath been able to observe, not onely that _Jupiter_ turns about upon his own Axis, but also the Time of such conversion; which he {144} estimates to be, 9 hours and 56 minutes.