1877.] Microscopy. 315 
American stands, he notices the greater prevalence than in England 
of stands having the limb supported by one pillar instead of two, though 
what happened to come before his notice gave a greatly exaggerated 
idea of the proportion of single-pillar instruments used here, the more 
general use of the [Zentmayer] glass stage, the general absence of a 
concentric stage rotation, except in the larger stands, the hinging of the 
mirror-stem for better managing oblique light, and the new plan of swing- 
ing mirror and substage together as now made by both Zentmayer and 
Gundlach. He mentions Zentmayer’s new portable microscope very 
favorably, along with one by Ross, and claims the centring adjustment 
now used on the best stands as his own, though contested by two claim- 
ants here. 
Of objectives he with very good taste hesitates to speak comparatively, 
adding a good-natured allusion to the well-known sensitiveness on this 
subject of makers, and the peculiar weakness of each for considering his 
own unquestionably the best in some important particulars. Subsequent 
discussion, however, drew out the opinion that the work of some Ameri- 
can opticians was very good, and differed from others (abroad) only in 
some few peculiarities. He had seen some of Mr. Tolles’ objectives 
which he had not found equaled elsewhere, though his impression was 
that he pushed the angle of aperture too far, and sometimes to the posi- 
tive detriment of his lenses. Microscopes of the better class he believed 
were produced in America fully as good as in England, though at far 
higher prices. Micro-photography he finds more extensively cultivated 
here than at home, with an evident influence on the construction of 
objectives, especially in regard to the angular aperture of the higher 
powers, the advantage of which he thinks is at least questionable, and 
from his own recent observations he is inclined to believe that “there are 
other and important directions in which the energies of those engaged 
in the manufacture of objectives can be more profitably employed.” 
He finds the accessories exhibited of the usual character, and not call- 
ing for special remark, though he states that he has had “ the pleasure of 
receiving many valuable hints respecting the improvement and modifica- 
tion of some of the accessories from Dr. Woodward, of Washington, Dr. 
J.G. Hunt and Mr. Holman, of Philadelphia, Dr. Ward, of Troy, and 
other microscopists,’”’ which he hopes to have an opportunity of carrying 
Out and submitting to further notice. 
The mounted objects by Mr. Walmsley, of Philadelphia, Dr. Beattie, 
of Baltimore, and Dr. J. G. Hunt, of Philadelphia are mentioned with 
praise; the vegetable preparations, transparent and double stained, by 
the latter person are regarded with evident enthusiasm as remarkable 
illustrations of vegetable structure mounted in an unsu manner. 
- Hunt's exquisite transparent vegetable preparations can hardly be 
better appreciated anywhere than here, but that they should now be re- 
garded as novelties is almost incredible. When first produced many years 
