102 General Notes. [Jan. 
can be oriented with reference to the sides of the paraffine-recep- 
tacle or with reference to lines drawn upon the surface of the 
bottle. 
When the cold water is allowed to enter in place of the warm, 
the paraffine congeals rapidly and may be easily removed as one 
piece. The discharge-pipe should open near the upper surface 
of the bottle, to draw off any air which may accumulate there.— 
E. A. Andrews. 
Orientation of Small Objects for Section-Cutting.—It i 
frequently a very difficult matter to properly orient small objects, 
especially spherical eggs, so that sections may pass through 
any desired plane. In my work on the embryology of the 
common shrimp I have found the following process very con- 
venient. Impregnation with paraffine is accomplished in the 
usual way, and then the eggs (in numbers) in melted paraffine 
. are placed in a shallow watch-crystal. They immediately sink to 
the bottom, and then the whole is allowed to cool. The crystal, 
glass upwards, is now placed on the stage of the microscope and 
the eggs examined under a lens. In this way one can readily 
see exactly how any egg lies, and then with a knife it may be 
cut out with the surrounding paraffine, and in such a way that it 
can readily be fastened to the block in any desired position. 
After all which have dropped in a suitable position are thus cut 
out, the paraffine is again melted, and after Stirring the eggs the 
cutting out is continued as before. —/. S. King. 
PSYCHOLOGY. 
The Perception of Space by Disparate Senses.—The follow- 
ing is an abstract of an interesting paper by Mr. Joseph Jastrow 
on the nature of space conceptions, contributed to Mind, vol. xi. 
p- 539. It records the result of experiments made on different 
persons at the viscid ga Reta Laboratory of the Johns Hopkins 
University, Ba 
In order to IONE the problem by experimental methods it 
will be necessary to define accurately such terms as sight, touch, 
motion. The following classification, though provisional and im- 
perfect, will perhaps be found convenient. We can obtain the 
notion of extension: 
= By the stimulation of a definite portion of a sensitive sur- 
(z) Of the retina mae the distance of the rupee. object 
{A Byr ie application of a pair of —_ leaving the inter- 
foe tim (a) it by the E 
