stupendous object. It is a vastly extensive branching and looped nebula, in the centre of the densest part of which is [Greek: e] Argus, itself a most remarkable star, seeing that from the fourth magnitude which it had in Ptolemy's time, it has risen (by _sudden starts_, and not gradually) to such a degree of brilliancy as _now_ actually to surpass Canopus, and to be second only to Sirius. One of these _leaps_ I myself witnessed when in the interval of ceasing to observe it in one year, and resuming its observation in two or three months after in the next, it had sprung over the heads of _all the stars of the first_ magnitude, from Fomalhaut and Regulus (the two least of them) to [Greek: a] Centauri, which it then just equalled, and which is the brightest of all but Canopus and Sirius! It has since made a fresh jump--and who can say it will be the last? One of the most beautiful objects in the southern hemisphere is a pretty large, perfectly round, and very well-defined planetary nebula, of a fine, full _independent_ blue colour--the only object I have ever seen in the heavens fairly entitled to be called _independently_ blue, _i.e._, not by contrast. Another superb and most striking object is Lacaille's 30 Doradus, a nebula of great size in the larger nubicula, of which it is impossible to give a better idea than to compare it to a "true lover's knot," or assemblage of nearly circular nebulous loops uniting in a centre, in or near which is an exactly circular round dark hole. Neither this nor the nebula about [Greek: e] Argus have any, the slightest, resemblance to the representations given of them by Dunlop.... As you are so kind as to offer to obtain information on any points interesting to me at Rome, here is one on which I earnestly desire to obtain the means of forming a correct opinion, _i.e._, the _real_ powers and merits of De Vico's great refractor at the Collegio Romano. De Vico's accounts of it appear to me to have not a little of the extra-marvellous in them. Saturn's _two_ close satellites regularly observed--eight stars in the trapezium of Orion! [Greek: a] Aquilae (as Schumacher inquiringly writes to me) divided into three! the supernumerary divisions of Saturn's ring well seen, &c., &c. And all by a Cauchoix refractor of eight inches? I fear me that these wonders are not for _female eyes_, the good monks are too well aware of the penetrating qualities of such optics to allow them entry within the seven-fold walls of their Collegio. Has Somerville ever looked through it? On his report I know I could quite rely. As for Lord Rosse's great reflector, I can only tell you what I hear, having never seen it, or even his three feet one. The great one is not yet completed. Of the other, those who _have_ looked through it speak in raptures. I met not