cm-) 
mahtng^ at ledB at tliskmffii] R eflexms on them. Arid the rather indeed , he« 
caufe I enjoyed fo little health, when / was making the Experiment s, that * twas 
not fit forme to engage in Speculations, that would much exercife mg thoughts , 
Wlhich, J doubt ^ have been more gratified, than my health hath been by the hare 
Trials, which are. moftfeafonahlg-'made at hours mfeafonable for one, that is 
not weU. 
T 0 S t S C RIFT 
Sent by the fame Noble Author- from the fame place, 
December 6. 1 66 j. 
fk yf" T condition in feint of health being not much improved fence 
[ VJ j writ to you in Q&ober laff, when 1 fhall have added, that I 
have not thefe five or fix weeks been able to procure any Shining 
Wood (t except one /ingle piece, which though large ', was fo ill condi- 
tioned, that it afforded me but one Trial) you. will not, I hope, expetf, 
that I fbouldadde much to the Experiments I formerly fent you about 
the Relation ’twixt Light and Air. But however , fence the fubjeff is 
New and Noble , and finccy our curio fit y about other matters/ has been fo 
welcome and ufeful to the Virtuofi, 1 [had not decline even on this oc- 
cafeon to comply with it, and the rather , be caufe I half promt fed you 
feme Additionals a good while fence, and becaufe too, that though, 
what I [hall acquaint you with , may feem to be but a Con firmation of 
two or three of the former Experiments, yet,beftdes that 9 tis of them, 
which moff needed a Confirmation, thefe Trials will alfo afford feme 
Circum fiances, that will not, I think, htunwelcom . 
Experiment XI. 
T O examine then the Conjecture, mentioned in the laft Ex- 
periment, That the durablenefs of the Light in the Shi- 
ning Fijh, in Tpight of the withdrawing the Air, might proceed 
in great pare from the Vividnefs of if, and the beauty of the mat- 
ter it refided in, rather than from the Extent of thp Luminous 
Body in com parifon of the fmall pieces of Shining Wood, I hither- 
to had made my Trials with*, 1 put in, the above-mentioned 
piece of Wood, whofe luminous fuperficies might be perhaps ten 
or twelve times as great, as that, which the Eye few at once of 
the 
