ON HIGH POWERS, AND A STEADY MICROSCOPE. 23 
this I emphatically answer ‘ No,’ in regard, for example, to 
the minute structure of nerve-tissue; and in this opinion I 
am fully borne out by the observations of Dr. Lionel Beale, 
who has probably done more good work with his 5th than 
any other observer. 
Extract IV. 
From the ‘ Intellectual Observer,’ page 129, September, 1864. 
“Mr. Thomas Ross can desire no higher testimony to his 
skill than the fact that both Mr. Brooke and Mr. Lionel 
Beale have seen extremely minute and very delicate objects 
with the new -1,th, in a manner that has not been surpassed 
by the performance of any other glass. Messrs. Powell and 
Lealand’s .4,th is so beautifully corrected as to leave very 
little possibility for improvement in this respect; but Mr. 
Ross may still be right im the opinion that minute glasses in 
the front of any combination tend to introduce certain errors 
of diffraction, and that, in stopping at his =,th, he is able to 
keep these errors down. When two great artists such as 
Ross and Powell both do their best, we cannot expect the 
balance of merit will be easy to discern; and it would require 
a prolonged and very elaborate series of experiments to de- 
termine whether anything uns can be shown with the ~;th 
can also be shown with ‘the 5 th, when raised to the same 
power. It is, however, certain, that if there be cases in 
which the ah would surpass ifs rival, they must be very 
few. The foremost obstacle to the use of the ;4th, and 
which does not affect the ;‘,th, is the closeness of its approxi- 
mation to the object; it cannot be worked through glass 
that will bear handling, and consequently it is better adapted 
for the display of a carefully prepared object than for research 
under the usual difficulties which the examination of tissues, 
&c., entails.” 
The first extract from the ‘Jurors’ Report’ undoubtedly 
leads every microscopist to believe that the objectives of 
Messrs. Powell and Lealand, from the ;!-th to the ~.th, were 
the best in the Exlibition, more especially the th. Nor 
were the jurors alone in this opinion; many coincided with 
them, and thought it well earned and well deserved. 
The second extract, from the President’s Address at the 
