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object of so mapping down even the fainter stars, that the 
asteroids which traverse this region may be the more readily 
recognised. In the maps thus constructed, we find star streams 
and star sprays as well marked as in Argelander’s chart. As 
the same general considerations apply in this case, it will be 
sufficient for me to invite attention to Figs. 4 and 5 ; but I 
would recommend the student who may possess Chacornac’s 
charts to study carefully the regions which surround the two 
spaces pictured in these figures.* 
If we pass on towards yet more remote depths, we still find 
well-marked signs among the stars of a tendency to form 
Fio. 4. 
A portion of one of Chacornac’s ecliptic charts, the centre of the space here 
shown being in 1° N. Dec., and 23h. 43m. R.A. 
streams and sprays. Sir John Herschel has pictured some very 
singular specimens of such streams, as seen in his eighteen-inch 
reflector during his survey of the southern heavens ; and 
doubtless, could the fields surveyed by the elder and younger 
Herschel be presented in maps, so that several adjacent fields 
could be seen at a single view, many other instances would be 
added to the list. 
It is scarcely necessary to add that the largest telescope ever 
made by man — the great Parsonstown reflector — has revealed 
* There is an interesting quotation at page 267 of Webb’s Celestial Objects , 
in -which Fr. Secchi describes the astonishment with which, when studying 
certain galactic regions, he saw spirals and curves of stars so regularly dis- 
posed as to preclude all possibility that chance distribution was in question. 
