482 PHILOSOPHICAL TRANSACTIONS. [aNNO 1773. 



compose the electric organ, with a representation of their horizontal partitions.— i. One of the 

 trunks of the nerves, with its ramifications. 



END OP THE SIXTY-THIRD VOLUME OF THE ORIGINAL. 



/. Observations on the Solar Spots. By Alexander Wilson, M. D., Prof, of 

 Astronomy, Glasgow. Anno 1774, Vol. LXIF. p. 1. 



Many astronomers of the first note were very early engaged in the inquiry con- 

 cerning the solar spots. Of all these Schiener and Hevelius deservedly hold the 

 first place, and nothing but the charms of so noble an investigation could have 

 induced them to prosecute their observations with so much assiduity. Scheiner 

 began his in l624, 14 years after Galileo had first made the discovery. In 

 1630, he at last published his Rosa Ursina, in which we have a detail of his 

 labours during that long interval of time. Hevelius came after Scheiner, and 

 diligently watched the appearances of the spots for 1 years, the result of which 

 application he has given in his Selenographia and Cometographia. 



But notwithstanding these attempts, so worthy of men actuated by a true 

 desire of knowledge, it must be confessed that nothing of moment has been 

 derived from them. If we except a few conclusions concerning the rotation of 

 the sun round his axis, and the inclination of his axis to the plane of the ecliptic, 

 every thing else, which has been inferred from the phenomena of the spots, 

 seems altogether to be matter of conjecture. Hevelius, from his great fondness 

 of the subject, and from a desire to avail himself of that long course of observa- 

 tion, to which he had so patiently submitted, has been led into many specula- 

 tions concerning the spots and the nature of the sun's body. In his Cometo- 

 graphia, p. 360, he furnishes us with a remarkable instance of this, which serves 

 to give us a view of the ideas he came to entertain on these subjects. But all 

 that we there find, however plausible and ingenious, can be regarded only as 

 conjecture. It does not appear, that any who have followed Hevelius have met 

 with more success. Their observations seem not to differ from his in any re- 

 markable circumstance ; nor do we find that their inferences from them, though 

 sometimes different, have any better pretensions to the truth. The many strange 

 and variable circumstances of the spots, which were discoverable from a minute 

 observation, still remained unaccountable; and we often find them at a loss in 

 framing any hypothesis, which could fully satisfy the mind concerning them. In 

 process of time atsronomers began to withdraw their attention from a subject 

 which remained so dark and perplexing, and for many years all researches of 

 this sort have been in a great measure laid aside. Chance, or a happy concur- 



