226 American PetrograpKical Microscopes. — Winchell 
except Mr. W. H, Bulloch, of Chicago. With a true American 
pride Mr. Bulloch responded with promptnesB, and in August 
1880 he sent to the University of Minnesota the first made 
American petrographical microscope. This instrument 
was furnished with the apparatus arranged in the manner then 
prevalent,and it is illustrated by the preceding plate which was 
made from a photograph taken when it was first finished. 
This instrument is accompanied by the following appliances, 
the numbers corresponding to the parts so designated in the 
plate, and described by Mr. Bulloch. 
No. 1, nose-piece containing Klein's quartz plate and Nicol prism. 
No. 2, Nicol prism. No. 3, centering nose-piece. No. 4, lower part of 
substage, containing prism which swings to one side. No. 6, centering 
substage. No. 8, lower part of goniometer. No. 9, upper Nicol prism. 
No. 10, plate of calc-spar cut perpendicular to the axis. No. 12, Hemi- 
sphere for use with convergent polarized light for showing crosses. 
No. J. 3, scale inside of tube. No. 15, extra nose piece. No. 16, supple- 
mentary substage. 
This microscope was exhibited at the Detroit meeting of the 
American Society of Microscopists, August 17, 1880,^ and is 
now owned by Dr. Edson Basten, of the Chicago College of 
Pharmacy, 3330 S. Park Ave., Chicago. Mr. Bulloch there- 
after illustrated and announced in his circular this litholog- 
ical microscope. Its price was $125. He subsequently made 
a more elaborate instrument for Mr. J. H. Caswell, of New 
York, author of the chapter on the microscopic petrography 
of the Black Hills of Dakota, published in Newton and Jan- 
ney's report on the geology of the Black Hills in 1881. The 
most elaborate and costly lithological microscope yet made 
by Mr. Bulloch was for Mr. F. E. Tyler, of Kansas City, Mo., 
at a cost of $300. This is shown in the cut on the following 
page. In the summer of 1880 Mr. Bulloch also altered two in- 
struments made before by him, so as to adapt them for litho- 
logical work, for Prof. R. D. Irving, of Madison, Wisconsin. 
Shortly after the enterprise of Mr. Bulloch, in the spring of 
1881, the "Acme lithological microscope" was made and ad- 
vertised by Mr. John W. Sidle, at Lancaster, Pa. The 
agency of the Acme microscopes passed to James W. 
Queen & Co., of Philadelphia, in November, 1881, and 
that firm has since continued their manufacture and sale, 
but without much effort to extend the lithological model. 
This microscope is of the usual style in its rotating stage 
2Sce their proceedings, Aug. 19. 1880. p. 12. 
