77/7? FRACTURE OF COMETS. 397 



the sun, consisting, as the spectroscope demonstrates, of 

 hydrogen flames and incandescent metallic vapors ejected 

 with furious violence to visible distances ranging from ten. 

 or twenty to above three hundred thousand miles, but this 

 flame shown by the spectroscope is but the flash of the gun, 

 the actual ejection proceeding vastly farther, far beyond 

 the limits of the corona, as described in last month's notes. 

 These eruptions are so abundant that Secchi alone observed 

 and recorded 2767 in one year (1871). Speaking generally, 

 the sun is never free from them, and they proceed from 

 all parts of the sun, but most abundantly from the sun-spot 

 /ones. 



A system of meteoric bodies such as I suppose to form a 

 comet (I mean the comet as it exists in space before the 

 generation of its tail, which is only formed as it approaches 

 the .sun) could not approach so near to the sun as did the 

 present comet at perihelion, without encountering more 

 or less of these furious blasts the flash of some of which 

 have been seen to move with a measurable mean velocity 

 of above 300 miles per second, and a probable maximum 

 velocity sufficient to eject solid matter beyond the reclaim- 

 ing grasp of solar gravitation. 



It is evident that such a meteoric system as I suppose to 

 constitute a comet would, iu the course of a rapid perihelion 

 flight crossing these outblasts, be liable to various degrees 

 of ejection in different parts, that would disturb its original 

 structure by blowing some of its constituents out of their 

 orbits, or even quite away from the control of the feeble 

 gravitation of the general" meteoric mass, and thus effecting 

 a rupture of the comet. 



Now such a disintegration or dispersion of the present 

 comet has been actually observed. Several able observers 

 have described a breaking of the head of this comet shortly 

 after its perihelion passage. Commander Sampson's obser- 

 vations with the great 26-inch equatorial telescope of the 

 Washington Naval Observatory are very explicit. On Octo- 

 ber 25 he saw the nucleus as a single well-defined globular 

 body. On November 3, with the same telescope, he saw a 

 triple nucleus, due to the formation of two additional 

 minor bodies. These were more distinctly seen on Novem- 



