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32
The Story of the Comets.
Chap.

T.M.E.C. and at Juvisy by Quenisset at 8h 55m T. M. E. C. show great bends (the latter one the stronger) in the tail at about the place where the condensations appear. It therefore seems that these masses were not thrown out by the comet's head, but caused by a localisation of the particles in the tail due to some encountered force. On the plate of October 16 these masses can still be seen about 11/2° from the head and connected with the newly-formed tail by slender threads of light.

About the middle of November a third distinctive feature developed. The comet was now characterised by long slender rays extending at measurable angles to the tail, and by undulations in the body of the tail itself. This appearance is most striking in the photograph of November 15 where slender streamers shoot out from the main body of the tail with tremendous velocity. The two on the s p side have very interesting structures. They are made up of still finer rays which cross each other alternately, and at the end make a bend in the direction of the comet's motion and then return to their original direction. At about 5° from the head the tail makes an abrupt turn toward the N. as if it had encountered a resisting medium. It is strongly convoluted on the n f side and full of detail through its whole length. On the following night, November 16, the entire aspect had changed. The coma was much stronger both visually and photographically. The tail showed marked signs of pulsations. On November 18 the comet was a beautiful object. The slender straight rays were predominant. The tail was broken into waves and a conspicuous dark streak extended along its N. side for some distance from the head.

On November 19, the head was seen to give off straight jets at small angles. The tail for a short way back was composed of individual strands which intertwined like the strands of a rope, whilst near the end they separated into broad ribbon-like bands.

It repeatedly lost its tail and formed new ones. Instead of submissively settling down to one of the three established types of comet tails, it took on a variety of types in one