ASTRONOMICAL INSTRUMENTS. 187 



there is little doubt that in process of time such an instrument 

 will become part of the regular stock in trade of a physical 

 observatory. 



It is impossible, in such a mere sketch as this must of necessity 

 be, to do more than indicate the ground covered by the Collection. 

 The Collection, however, speaks most eloquently for itself, and, 

 thanks to observers in this and other countries, there is no part of 

 the domain, either of mechanical or physical astronomy, which is 

 not illustrated, either by objects of historical interest or by instru- 

 ments of more recent cfate, which have aided observations or 

 experiments destined to long outlive those who used them. 



J. NORMAN LOCKYER. 



