1058 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



myxamceba) and plasmodia, is inverted, instead of hanging down from 

 tho under side of the eover-glass c into the cavity of the bibulous 

 paper cell b (fixed to the slide a). A piece of hyacinth root g passes 

 into the drop, being suspended by a glass filament f supported by a 

 cork e. The whole is placed in a larger damp chamber, and the root 

 kept thoroughly wet. 



Apparatus for the microscopic detection of Rhombic Pyroxene.* 

 — Dr. E. Kiich uses the contrivance shown in fig. 230 to determine 



hypersthene where this mineral 

 is present in a rock with a 

 larger proportion of monoclinic 

 augite. 



The cylindrical brass pillar 

 b (2-3 cm. in height) is fixed 

 on a brass plate a, 1 cm. broad 

 and 1 mm. thick ; a hole is 

 bored at the upper end, and 

 through this passes a hollow 

 cylinder which can be rotated, 

 but cannot be shifted to right 

 or left on account of the 

 collars c c. The screw d serves to fix the cylinder to b ; through 

 the cylinder pa^es the rod e, which can be moved to right or left 

 and is fixed by the screw /. This rod terminates at one end in the 

 clamp g. The apparatus is fixed on the stage by two screws, so that 

 the prolongation of e passes through the axis of the Microscope. 



To use the apparatus the pyroxenic constituent is isolated and 

 fixed with Canada balsam between two cover-glasses, which are then 

 placed in the clamp g ; by moving e and the slide itself one crystal 

 after another is so placed that its crystallographic vertical axis coin- 

 cides with the axis of e ; /is then clamped, and each crystal may then 

 be turned about its vertical axis and the extinction tested in different 

 positions, care being taken to clamp the screw d when the stage is 

 rotated. 



Sahli's Automatic Regulator for an Incubator heated by 

 Petroleum.j — Dr. H. Sahli's apparatus, the general appearance of 

 which is shown in fig. 231, consists of an iron vessel ABC (fig. 232) 

 divided into (1) a hot-air chamber A C, (2) the incubator proper, and 

 (3) a space filled with water surrounding the latter. From the air- 

 chamber descends a pipe D, into the lower extremity of which the 

 chimney of the lamp fits. On one side is a shaft K, to which at its 

 junction with D is attached a valve H J moving on a hinge at H. 

 H G is a lever raised by the needle W. 



The lamp is provided with two chimneys ; the smaller used for 

 incubations, the larger for sterilizing. The regulator apparatus 



* Neues Jahrb. f. Mineral., Geol. u. Palseont., i. (188G) pp. 35-48 (2 figs.). 

 t Zeitschr. f. Wiss. Mikr., iii. (1886) pp. 165-73 (3 figs.). 



