796 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Mr. Zentmayer was not willing to push himself forward, but when ho 
was at last pursuaded to lecture on optics at the Franklin Institute, his 
lecture proved to he as well worthy of the man as all his mechanical work. 
It stands to-day as an important addition to the literature of optics. 
Mr. Zentmayer’s musical education, as well as his artistic, made 
him an appreciative critic, and among his countrymen his poetry is 
valued. He was so loving and so kind, so winning in his ways, that 
all who came in contact with him were attracted towards him, and when 
his last illness came, warning them that the mind they had valued so 
highly was losing its great strength, they mourned his death long before 
the actual dissolution of his body. 
The illness that at last resulted in the death of Mr. Zentmayer came 
on very slowly, and fortunately only after he had instructed his sons in 
the processes that had made his work so celebrated. Those sons have 
had charge for a number of years of the construction of the instruments 
which have given such great satisfaction to all who have used them. 
To members of the committee of the Franklin Institute the father con- 
fided his system of education of his children, and to them he explained 
how thoroughly he had informed them of the minutiae of his operations 
that they might worthily carry on a business of which he was so proud. 
Mr. Zentmayer would never do any work slightingly. What was to be 
done must be done well, his constant effort being to improve his methods 
as well as improve the construction of his instruments. 
As a writer Mr. Zentmayer was not prolific, preferring to express 
his ideas verbally to his friends rather than to put them on paper for 
publication. We find, however, the following articles which were his 
work in the * Journal of the Franklin Institute’ : — 
“ On a Mechanical Finger for Use in Mounting Diatoms under the 
Microscope,” 1870, vol. lxxxix. p. 334. 
“ On an Erecting Prism for Use in the Microscope,” 1872, vol. xciii. 
p. 375 ; “A Lecture on Lenses,” 1877, vol. civ. p. 49. 
Also in the * Philadelphia Photographer,’ 1867, vol. iv. p. 251, we 
find an article entitled “ Kefraction without Dispersion, and some 
Beflections,” in which he takes a hand in the controversy about his 
photographic lens with marked ability.” 
/3. Technique.* 
N a bias, B. de, & J. S abrazes— Bemerkungen iiber einige Punkte der histo- 
logischen und Bakteriologischen Technik. (Remarks on some points in Histo- 
logical and Bacteriological Technique.) 
Prcig. Med. Wochenschr., 1893, pp. 286-8. 
Cl) Collecting 1 Objects, including- Culture Processes. 
Non-albuminous Nutritive Solution for Pathogenic Bacteria.f — 
Dr. Uschinsky has devised a non-albuminous medium for cultivating 
pathogenic microbes in which they grow as luxuriantly as in ordinary 
bouillon. The solution is composed of the following ingredients : — 
* This subdivision contains (1) Collecting Objects, including Culture Pro- 
cesses ; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; 
(4) Staining and Injecting ; (5) Mounting, including slides, preservative fluids, &c. ; 
(6) Miscellaneous. 
t Centralbl. f. Bakteriol. u. Parasitenk., xiv. (1893) pp. 316-9. 
