132 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
find is raised by means of a graduated micrometer screw. The sliding 
of the knife is effected by a crank so that the irregularities of movement, 
inevitable when the hand alone is used, are avoided. 
A New Section-stretcher.* — Prof. G. Born describes a new device 
for preventing paraffin-sections from rolling up. It depends upon the 
principle of holding down the section with a minimum amount of force. 
The apparatus employed for this purpose consists, as shown in fig. 16, of 
an equilibrated lever a which turns very easily about a horizontal axis x 
fixed in a fork g. This fork can be displaced along a horizontal rod and 
Fig, 16. 
fixed in any position by means of a screw. The horizontal rod can be 
adjusted in height on a vertical holder. The lever carries at one end a 
small flat spring-clamp z, in which is fastened a piece of paper p, rounded 
or cut square at the free end. The weight of the paper is not sufficient 
to disturb the equilibrium of the lever in favour of the arm a r A small 
rider of wire is therefore placed in one of the notches on the upper edge 
of the lever. The instrument is so adjusted that the free end of the 
paper lies on the front edge (the edge turned towards the knife) of the 
paraffin-block P. During the forward motion of the knife through 
the paraffin-block the paper keeps the section on the blade. The section 
can then be very easily removed with a broad needle. When the knife 
* Zeitsehr. f. wiss. Mikr., x. (1893) pp. 157-60. 
