_P. S._ During my passage from Russia we very rarely had any _aurora borealis_; and those few we saw were faint, and of short continuance: at which I was much surprised; for about ten years ago, being in a high north latitude, we had very beautiful ones almost every night in the month of September; which exceeded any I have seen described in the _Philosophical Transactions_, or _Memoires de l’Academie Royale_. Wm. Chapman. LXXXVIII. _Observatio Eclipsis Lunaris facta_ Matriti _a Pª._ Joanne Wendlingen, _Societatis_ Jesu, _in Regali Observatorio Collegii Imperialis ejusdem Societatis, Die_ 30 Julii 1757. _Quælibet observatio bis instituta fuit, semel interjecto oculum inter lentemque ocularem vitri clari, cærulei, plani, ac bene tersi, fragmento. Hæ observationes notantur hac voce_ cerul. _Telescopium, quo usus sum, est_ Gregorianum _trium pedum_ Anglicanorum, _omnino præclarum_. _Communicated by_ Matthew Maty, _M. D. F.R.S._ [Read April 20, 1758.] IMMERSIONES. |Tempus verum| Differentia | h ´ ´´ | PRincipium eclipsis, _clar._ | 9 47 34 | Mare Humorum, _clar._ | -- 52 47 | { _cær._ | -- 54 28 | ´´ Grimaldus { _clar._| -- 55 27 | ---- 59 {_cær._ | 10 1 21 | ---- 13 Bullialdus {---- | 10 1 34 | {---- | -- 9 35 | ---- 10 Keplerus {---- | -- 9 45 | {---- | -- 16 15 | ---- 12 Copernicus {---- | -- 16 28 | {---- | -- 18 14 | ---- 10 Heraclides {---- | -- 18 24 | Manilius {_clar._ | 10 30 43 | ´´ {_cær._ | 10 30 54 | ---- 11 Menelaus {---- | -- 34 11 | ---- 9 {---- | -- 34 20 | Promontorium {---- | -- 44 49 | ---- 9 {---- | -- 44 58 | Mare Crisium {---- | -- 45 33 | ---- 11 {---- | -- 45 44 | Proclus, _clar._ | -- 46 54 | {---- | -- 54 48 | ---- 14 Plato {---- | -- 55 2 | {---- | 11 7 3 | Langrenus {---- | 11 7 23 | ---- 20