Account of the Russian Discoveries between Asia and America / To which are added, the conquest of Siberia, and the history of the transactions and commerce between Russia and China

by William Coxe

The comparison of the following results, deduced from corresponding observations[132] of the eclipses of Jupiter's satellites taken at Bolcheresk at the port of Peter and Paul by Krassilnikoff, and at Pekin by the Jesuit missionaries, will shew from their near agreement the care and attention which must have been given to the observations; and from hence there is reason to suppose, that the suspicions of inaccuracy imputed to Krassilnikoff are ill founded.

1741, Old Stile.
	h	´	´´
Jan. 27, Em. I Sat.	12	9	25	at the port of St. Peter and Paul
	9	20	35	at Pekin.
Difference of the meridian at Pekin and the Port	2	48	50
	h	´	´´
Jan. 30, Imm. III Sat.	12	5	30	at the Port.
	9	16	30	at Pekin.
	2	49	0
	h	´	´´
Feb. 5, I Sat.	8	33	26	at the Port.
	5	43	45	at Pekin.
	2	49	41
	h	´	´´
Feb. 12, Em. I Sat.	10	28	49
	7	39	29
	2	49	20
And the longitude from Paris to Pekin being	7	36	23
The difference of the meridians of Paris and thePort will be	10	25	36
Which differs only 31 seconds from the determinationof Mr. Maraldi.
1741. Old Style.
	h	´	´´
March 23, Em. II Sat.	10	55	2	at Bolcheresk.
	8	14	0	at Pekin.
	2	41	2
	h	´	´´
Dec. 31, Im. I Sat.	10	51	58	at Bolcheresk.
	8	9	45	at Pekin.
Difference of the meridians of Pekin and Bolcheresk	2	42	13
	h	´	´´
By taking the medium the difference of thelongitude between Bolcheresk and Pekin will be found to be	2	41	37
Between Bolcheresk and Paris	10	18	0
Which differs only one minute and one second fromthe determination of Mr. Maraldi.

In order to call in question the conclusions drawn from the observations of Krassilnikoff, Monsieur de Vaugondy pretends that the instruments and pendulums, which he made use of at Kamtchatka, were much damaged by the length of the journey; and that the person who was sent to repair them was an unskilful workman. But this opinion seems to have been advanced without sufficient foundation. Indeed Krassilnikoff[133] himself allows that his pendulum occasionally stopt, even when necessary to ascertain the true time of the observation. He admits therefore that the observations which he took under these disadvantages (when he could not correct them by preceding or subsequent observations of the sun or stars) are not to be depended upon, and has accordingly distinguished them by an asterisk; there are however a number of others, which were not liable to any exception of this kind; and the observations already mentioned in this number are comprised under this class.

If the arguments which have been already produced should not appear sufficiently satisfactory, we have the further testimony of Mr. Muller, who was in those parts at the same time with Krassilnikoff, and who is the only competent judge of this matter now alive. For that respectable author has given me the most positive assurances, that the instruments were not damaged in such a manner as to effect the accuracy of the observations when in the hands of a skilful observer.

Accuracy of the Russian Geographers.

That the longitude of Kamtchatka is laid down with sufficient accuracy by the Russian geographers, will appear by comparing it with the longitude of Yakutsk; for as the latter has been clearly established by a variety of observations, taken at different times and by different persons, if there is any error in placing Kamtchatka so far to the East, it will be found in the longitude between Yakutsk and Bolcheresk. A short comparison therefore of some of the different observations made at Yakutsk will help to settle the longitude of Kamtchatka, and will still farther confirm the character of a skilful observer, which has been given to Krassilnikoff.

Krassilnikoff in returning from Kamtchatka observed at Yakutsk several eclipses of the satellites of Jupiter, of which the following are mentioned by him as the most exact.

1744, Old Style.
			h	´	´´
[134]Feb. 7.	Imm.	I. Sat.	11	18	35	somewhat doubtful.
22.	Imm.	II. Sat.	10	31	11	} all exact.
29.	Imm.	II. Sat.	13	6	54
Mar. 1.	Imm.	I. Sat.	11	23	0
Apr. 9.	Em.	I. Sat.	12	23	50