A New Erecting Arrangement. 11 



finest lines of the nineteenth band plate " have never been as yet 

 fairly resolved." * 



In the following spring, however, having received an immersion 

 ^th from Messrs. Powell and Lealand, I was so fortunate as to 

 effect undoubted resolution of the refractory bands, and to furnish 

 a count of the number of lines ; and now Dr. Barnard, as his recent 

 paper shows, reconsiders his own judgment of his own work, and 

 claims to have effected true resolution with the drij Spencer's tV ^h, 

 though he writes me he still admits the lines shown by the dry ith 

 to have been spurious. I confess I am not convinced by his present 

 reasoning that the judgment deliberately announced in his public 

 lecture of November 25, 1868, was erroneous, and must continue 

 to believe that a method which has permitted so careful and con- 

 scientious an observer to contradict his own conclusions in this 

 manner, ought not to be preferred to the more accurate and abso- 

 lute criterion of resolution which I have proposed for the higher 

 bands of the plate. 



IV. — A New Erecting Arrangement, especially designed for Use 

 with Binocular Microscopes. By E. H. Ward, M.A., M.D., 

 Professor of Botany and Microscopy in Eensselaer Polytechnic 

 Institute. 



For dissecting and other manipulations under magnifying powers, 

 the simple microscope is awkward and unsatisfactory, and has been 

 made to serve as a binocular only with very low powers ; but the 

 superb field of the compound microscope has been comparatively 

 little used for these purposes, because few persons can work to 

 advantage under an inverting arrangement; the erectors usually 

 furnished are not good, and the use, otherwise satisfactory, of a 

 good objective as an erector has not as yet afforded the advantage 

 of binocular vision. The simple expedient now proposed is designed 

 to increase the usefulness of the stereoscopic binoculars in ordinary 

 use by rendering them easily available for purposes which require 

 an erect image. 



Last summer, the writer proposed, at the Indianopolis Meeting 

 of the American Association, to place, for certain purposes, an 

 erecting objective below instead of above the regular objective of 

 the microscope. Then, of course, the regular objective becomes the 

 erector, and the accessory one below acts as the objective. This 

 simple expedient, applied to Wenham's and other non-erecting 

 binoculars, leaves little to be desired for the purposes of a dissect- 

 ing microscope. The lenses of a 1;| or 2 inch objective (preferably 

 a solid or single-combination one) may be packed or screwed into 



* ' Annual Report of the American Institute of the City of New York for the 

 year 1868,' No. IX., page 43. 



