24 A. C. D. CROMMELIN, ‘ESQ., D.SC., F.R.A.S., ON 
and doubtful. In the last few years a large piece of compu- 
tational work, in which I have borne a part, has been carried 
out, with the object of testing Hind’s list. 
The effect of the planets on the period of the comet has been 
calculated for each revolution, and conjecture has given place 
to certainty. On the whole Hind’s list was singularly 
accurate, but he was seriously wrong in two cases; in A.D. 608 
he was one and a half years too late, and in A.D. 1225 nearly a 
year too late. The history of the comet now extends with 
certainty to 240 B.c., and with some degree of probability to 
613 B.c., in the autumn of which year a comet passed through 
the Great Bear. The great cometographer Pingré fancied that 
this comet might be alluded to by the prophet Jeremiah (i, 13) ; 
“T see a boiling caldron, and the face thereof from the face of 
the north.” He even conjectured that the “rod watching” in 
verse 11, might be the tail of the comet; Pingré suggested that 
the tail was seen before the head had risen; when the latter 
appeared it resembled a caldron with steam rising from it. 
The insertion of the word “north” lends colour to the sugges- 
tion that a celestial apparition may be indicated. 
These guesses seem to me to be extremely doubtful, but 
the interest of finding a possible reference to our comet in 
Scripture justified us in quoting them. Two revolutions later, 
in 467 B.c., both Anaxogoras and Aristotle relate that a 
meteoric stone fell at Aegospotami, and that a comet was seen 
at the same time. It is interesting to find these events 
mentioned in juxtaposition at such an early date. This comet 
was also seen in China, but unfortunately no details are given 
of its track through the constellations, so its identification is 
doubtful. Three revolutions later we come to our first certain 
identification, in 240 B.c., when the Chinese annals state that a 
comet was seen first in the east, then in the north, and finally 
for sixteen days in May in the west. The return in 12 B.C. is 
interesting, being so near the birth of Our Lord, which 
according to the date assigned by Lt.-Col. Mackinlay, fell four 
years later. This comet is described with great fulness in the 
Chinese annals, to which we are indebted for most of our 
knowledge of ancient comets; the European records are far 
Jess precise, and in this case simply relate that “A comet was 
seen for several days, it appeared suspended over the city of 
Rome; then it appeared to break up into several little torches.” 
Halley’s comet next appeared in A.D. 66, January, four years 
before the fall of Jerusalem. It is not impossible that this 
was the comet resembling a sword, which according to 
