XLVIII. _Observationes Eclipsium Satellitum Jovis Ulissipone habitæ à_ Joanne Chevalier, _Presbytero Congregationis Oratorii, Regiæque_ Londinensis _Societatis Socio, Anno 1757_. [Read Dec. 8, 1757.] TElescopio Gregoriano 7 pedum observavi emersionem primi satellitis die 7 Junii cum cœlum serenum ac clarum esset, hora postmeridiana temporis veri 10ʰ 29’ 12” Die 8 Junii eodem telescopio observavi emersionem secundi satellitis hora postmeridiana 8ʰ 32’ 48” cœlum aliquantum nubilum erat. Eadem die observavi emersionem tertii satellitis hora postmeridiana 9ʰ 36’ 25” cœlo claro. Die 15 Junii cœlo claro observavi emersionem secundi satellitis hora postmeridiana 11ʰ 6’ 15” Sequenti die 16 Junii observavi immersionem tertii satellitis hora matutina temporis veri 0ʰ 0’ 29” XLIX. _A remarkable Case of the Efficacy of the Bark in a Mortification. In a Letter to_ William Watson, _M.D. F.R.S. from Mr._ Richard Grindall, _Surgeon to the_ London _Hospital_. [Read Dec. 8, 1757.] Austin-Friars, Dec. 7th, 1757. SIR, THE following case being very singular has induced me to lay it before the Royal Society, and beg the favour to do it through your means. Although numerous instances are related in the records of medicine, of the great danger in interrupting nature in her operations, there is not one (so far as I know), in which more violent and extraordinary effects have been produced, than in the following. It may happen also, that this instance may be of service in ascertaining the virtue of the medicine in intermittents, when in the hands of men of judgment.