178 



THE AMERICAN MONTHLY 



[September, 



— The minute size and extremely viru- 

 lent properties of some of the septic 

 bacteria is surprising. The septic bac- 

 teria, or bacetria of putrefaction, are 

 those which are found in the animal 

 body after death. They are supposed to 

 be quite distinct from the patliogenic 

 bacteria. It is remarkable that some of 

 the septic organisms seem to be confined 

 in their effects to certain animals. Thus, 

 Davaine's septicaemia in the rabbit is not 

 dangerous to man, cattle, horses, sheep 

 or dogs. Mr. G. F. Dowdeswell, M. A., 

 has described a form occurring in the 

 lung of a mouse infected with septicemia, 

 which he regards as the smallest known 

 organism. It is a form of bacillus, the 

 cells of which are about o.ooi mm. or 

 ■JToTo "-"^ ^" '"^h "^ length, by less 

 than iTjoVoo °^ ^'"^ ''^'^l"' ^^ breadth. In 

 the case of the septicaemia of the rabbit, 

 the number of organisms in the blood was 

 estimated as upwards of 3,000 millions in 

 a single drop ; and probably a still larger 

 number of these very minute bacteria 

 would be found in the same quantity of 

 blood containing them. 



— Mr. J. Horn of Scarborough, Eng- 

 land, lias devised a method of mounting 

 very minute animals, such as embryonic 

 fishes for example, in a medium which 

 makes them transparent, and causes but 

 very little contraction of the internal 

 parts. At present the composition of 

 the fluid used is not made known, but 

 probably it will be published before long. 



— Mr. W. P. Collins, 157 Great Portland 

 St., London, has just issued an advance 

 edition of a catalogue of new and second- 

 hand books and publications relating to 

 microscopy. Mr. Collins is, we believe, 

 the only dealer in scientific books in the 

 world who gives special attention to 

 works on the microscope, and in his new 

 catalogue are mentioned numerous rare 

 and valuable books now on hand. In 

 order that persons in foreign lands may 

 have an opportunity to obtain such books 

 as they desire, a special edition of the 

 catalogue will be sent to the United 

 States and to other foreign countries a 

 month sooner than the home-edition will 

 be circulated. Among the special fea- 

 tures of the catalogue may be men- 

 tioned : a list of important papers taken 

 from Journals, transactions of societies, 

 etc., and bound separately in paper covers ; 

 a list of works, English and foreign, 

 issued since 1881 ; an index to works on 

 general microscopy and to special bran. 



dies of microscopical literature. In Oc- 

 tober Mr. Collins proposes to begin the 

 publication of a monthly list ol general 

 scientific works. Microscopists who de- 

 sire to keep up with the literature relat- 

 ing to any branch of microscopical study, 

 will find Mr. Collins's catalogues invalua- 

 ble. 



— One of our most prominent and 

 widely known scientific exchanges, on 

 reviewing a late work on Photo-Micro- 

 graphy, is of the opinion that Micro-pJio- 

 grcipliy is " a term more definite than the 

 inverse of p}wto-))iicrography chosen by 

 the author." 



— We extract the following from a 

 medical pamphlet by R. J. Nunn, M. D. 

 of Savannah, Ga. 



The Pillar Slide. — A new slide for 

 the microscope. — Take a small thick 

 cover-glass, and cement it on the center 

 of the slide with Canada balsam, and let 

 it harden thoroughly. To use it, a drop 

 of the fluid to be examined is placed 

 upon the pillar just described, a cover 

 larger than the pillar is placed upon it, 

 when it will be seen that the excess of 

 fluid flows into the annular space sur- 

 rounding the pillar. The advantages 

 claimed for this slide are that it does 

 away with the necessity for the use of a 

 bibulant to absorb an excess of the fluids 

 which is almost always present in the 

 usual mode of examining them, and also 

 that evaporation may take place for a 

 considerable time from the annular space 

 without affecting the film; — it is also 

 very useful in making chemical tests. 



— In the August issue of the Kansas 

 City Rcviciu of Science and Industry. 

 Mr. Wm. Dawson gives an interesting 

 table of all the Eclipses of the Sun and 

 Moon for the present century (1800 to 

 1900). During the fiibt half of the cen- 

 tury there were 199 eclipses and 196 to be 

 in the second half, or 395 in all, there 

 being 68 more to occur. The greatest 

 number occurring in one " United States 

 year," was six, but an eclipse of the sun 

 occurred 1804, Dec. 31, 8 p.m. which was 

 January ist, i A. M., 1805, in England, 

 and there being six eclipses after this one 

 in tliat year, there were seven (the great- 

 est number tliat can ever be in one year) 

 in 1805, in the Eastern Hemisphere 

 and only six in the Western. A simi- 

 lar occurrence took place four hours 

 after New Year's Day, 1824, and as 

 there were six eclipses, in 1823, it was 



