for the Photographic Camera. 323 
with sharpness, admitted, at 
In the English journals, when the accounts of this instrument 
tortion to marginal lines, but since it has been proved to be no 
failure, and its success is no longer an experiment, comes the 
declaration that it is “ old, very old.” Everybody had been 
making them for years and there is no merit of invention due to 
the patentees! Granting that lenses may have been made with 
an external spherical focus, as is the Sutton case, it will be dif- 
t to produce a lens, made previous to the invention of this 
how described, composed of two achromatic meniscus lenses com- 
hed as these are and producing a like result. The theory of 
Operation and mode of construction of the globe lenses admit of 
their bein g readily made of various focal lengths, and thus, by the 
of a series of instruments, the whole included angle can be 
made available on any size plate that may be desired; the six 
Meh focus coverin ga 64x84’ plate and the 12” focus lens cover- 
ing 14" 18" each including the same angle. One great advan- 
tage of short-focus lenses, when there is no spherical distortion, is 
'n the appearance of perspective produced. If, for instance, we 
Would view a machine or statue to the best advantage, we stand 
at such a distance from it as will admit of our viewing the whole 
Now a picture be made by an instrument of long focus, it 
. 
iv 
(the 23” focus), this perspective effect may be too much exag- 
the a sizes it is not, and with the globe 
_ Year or so ago, Messrs. E. and H. T. Anthony pu 
Of ster graphs of Niagara, which seemed to me when I first saw 
: them to bring to my mind all the wonders of the stupendous 
