218 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



Mounting Desmids.* — G. H. Bryan uses a small box ma<le of parch- 

 ment-paper. The water containing the desmids is placed in the box, 

 which is floated on glycerin. In two days the water will have diffused 

 into the glycerin and sufficient glycerin into the desmids. They are 

 then ready for mounting in glycerin. 



(6) Miscellaneous. 



New Test-tube Stand-t — Dr. R. J. Petri has devised a convenient 

 stand for ten tubes (fig 35). It is made entirely of metal, the base 



Fig. 35. 



and^uprights consisting of iron or zinc. The new stand is more compact 

 and takes up much less room than a wooden one, and is specially adapted 

 for laboratories. 



Quickly-made Glass Cell 4 — H. A. Doty places a cover-glass of the 

 desired thickness on a turn-table together with a minute drop of water, 

 by means of which the cover-glass is held firmly enough to permit circles 

 being cut upon it with a diamond. As it is rarely possible to free the circle 

 from the ring without breaking the latter, it is advisable to cut the ring 

 across with the diamond, after which it is more easily detached. The 

 cross-cut does not impair its efficiency as a cell when it has been cemented 

 on to the slide, jfe^ggga* 



Mechanical Finger. § — H. A. Doty has devised a mechanical finger 

 which allows the rod carrying the bristle to be instantly removed 

 (fig. 36), the pin in the end of the rod being also removable, so that 

 several sizes and forms of bristles may be employed, without loss of 

 time, upon the same piece of work. The other adjustments are so clearly 

 shown in the illustration as to need no further description. 



Measurement of Bacteria.jJ — E. Greig Smith states that the method 

 he employs in determining the breadth of an organism is to fix on a 

 bacterium in the microscopic field and measure its length. He then 

 compares the organism with a series of diagrams representing bacteria, 

 the breadths of which have been accurately measured in terms of the 



* Journ. Applied Microscopy, iii. (1900) pp. 1027-8 (2 figs.). 



t Centralbl. Bakt., 1" Abt., xxviii. (1900) pp. 747-8 (1 fig.). 



t Jouru. Applied Microscopy, iii. (1000) pp. 990-1. 



§ Tom. cit., pp. 991-3 (2 figs.). 



|| Proc. Linn. Soc. N.S.W., xxv. (1900) pp. 533-6 (3 figs.). 





