The Astronomical Outlook 



ocular observations. This is not to be taken as 

 a prediction that such ideal photographic perfec- 

 tion will soon, or ever, be actually attained; but 

 if it is even approached the whole aspect of 

 observational astronomy will be changed: the 

 human retina* will have been practically sup- 

 planted by the photographic film. 



Even more important, from some points of 

 view, is the probable, or at least possible, develop- 

 ment of astronomical mathematics. The astron- 

 omer is now confronted with numerous problems 

 relating to the motions of groups of bodies under 

 their mutual attraction, and while these prob- 

 lems are in their nature prefectly determinate 

 and capable of solution, we have as yet no mathe- 

 matical methods able to deal with them in a satis- 

 factory manner. We may at least hope that the 

 reproach will be removed before very long; that 

 some new functions or methods may be found 

 which will increase our powers of computation as 

 greatly as did the invention of logarithms and of 

 the calculus. It is true that the want has been 

 pressing for nearly two hundred years and that 

 failure has followed failure in the attempt to 

 supply it. Doubtless, therefore, we ought not to 



* One wonders sometimes whether there cannot be found 

 some way to exalt the sensitiveness of the retina itself; 

 some drug, for instance, that will for a short time so increase 

 the power of seeing a faint object as virtually to give, for 

 the time being, the advantage of a larger telescope. It is 

 very tantalizing to be able barely to see a faint object but 

 not clearly enough to measure it a very common experience 

 of every observer. 



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