282 American Microscopes [Soumnal, Nov. 1 lar. 
shown from the makers’ price lists that the cost was much higher 
than Tolles’ prices for similar objectives, and yet Dr. Hagen elects 
to repeat his erroneous statement. He said then that he ‘ spoke 
for the interest of science.” Can the interest of science be pro- 
moted by such misstatements? It was not the intention of the 
writer to have said anything more on the matter of cost, but while 
writing this paper a letter was received, an extract from which is a 
good comment on all that Dr. Hagen has said as to cost and work- 
manship. It is not known that the writer of the letter ever heard 
of Dr. Hagen or his comparisons. The letter was written by 
Colonel J. G. F. Holston, M.D., Washington, D.C., June, 1870. 
“T was never dissatisfied either with Tolles’ prices or his workman- 
ship, for although apparently dearer than some other makers, the 
superior excellency more than balances it. I can do with my 7th 
by Tolles (cost $100) all that Powell and Lealand’s joth will do 
well that cost the United States 8350. I compared them myself 
at the museum.” Dr. Barnard, President of Columbia College, 
New York, writes :—‘“ Dr. Hagen is absurdly wrong in his compa- 
rison of the performance of the American and foreign objectives of 
the same price.” “It is nonsense to make such comparisons as 
these price for price.” 
No less unfortunate is Dr. Hagen in his description of Tolles’ 
first-class instruments; he partially describes the plan and con- 
struction of some instruments which he had seen—omitting, how- 
ever, some of the most peculiar details—and mixing with that 
some of the peculiarities of a unique instrument, the only one of 
the kind ever made, and which he has never seen, the particulars 
of which he could have got from Dr. Barnard’s report of the Paris 
Exposition of 1867—constructing in this way an instrument which 
has no existence. He claims to have “seen and tested nine of 
Tolles’ instruments of the largest class.” The writer will not say that 
is impossible, but he can say that there are no nine instruments of 
the “largest class” known to Mr. Tolles that Dr. Hagen could 
possibly have seen and tested. His classification must be treated 
as an error until he furnishes a list of the nine. ‘The self-suffi- 
ciency with which he charges the reverend President of Columbia 
College with making, in his official report of the Paris Exposition, 
a claim that is “hardly tenable” is, to use his own expression, 
“quite comical.” Dr. Barnard had reported that “it was to be 
regretted that the American makers did not send” stands to the 
exhibition ; for the want of them the objectives were not properly 
examined. Dr. Hagen twists this round in this way, “ The same 
objectives are frequently used here with English stands and oculars, 
plenty of which were to be had in Paris. If, then, they did not 
prove themselves successful, the reason must be that they did not 
attain as much as others. The circumstances of the difficulty of 
