Mr. goodricke’s Account^ &c. 
The firft time I faw it vary was on the 12th of November 
1782, between eight and nine o’clock at night, when it ap- 
peared of about the fourth magnitude ; but the next dav it was 
of the fecond magnitude, which is its ufual appearance. On 
the 28th of December following, I perceived it to vary again 
thus ; at 5 °f h. in the evening, it was about the fourth magni- 
tuae, as on the iatn or November laft; but at Si h. 1 was 
much furprized to find it fo quickly increafed as to appear of 
the fecond magnitude. My friend Mr. Edward pigott, whom 
I informed of this Angular phenomenon as foon as l’faw it, 
alfo oblerved it ; and I had the pleafure to find that his obfer- 
vations coincided with mine. The fubfequent obfervations 
which I have made on this flat are very particular; and I think 
it will be bell: to give a brief extra* of them in their order 
from my journal; but it is neceflary I Ihould firft fpecify the 
ufurd and greateft magnitude of Algol, as alfo the relative 
brightnefs and magnitude of thofe ftars to which I compared it 
during tire progrefs of its variation. 
_ The ulual and greateft magnitude of Algol is this; of the 
fecond magnitude, much left bright than « Perfei, and not fo 
much as y Andromeda;'; brighter than « Caffiopeie and )3 Arie- 
tis, and neai Iv the fame, it not rather brighter, than « Pe^aft 
and p Caffiopeie ; itot quite fo bright as y Caffiopeie, and much 
brighter than s Perfei and /3 Trianguli. The relative bright- 
nefs of the ftar? to which I compared it during the progrefs of 
its variation is as follows; « Caffiopeie Is the brighfeft, and of 
. ma, the lecond magnitude ;' /3 Arietis is the next, and of be- 
tween die fecond and third' magnitude ; then t Perfei and /3 
Trianguli, both of the third magnitude ; f Perfei is fomewhat 
lei's bright than « Perfei, mid alfo of tlie third magnitude ; 
' c Perfei is left than f Perfei, and rather of between the third 
and 
