the outer rim of a thin compass card divided into degrees pasted on to
it. The hour circle, F, is half of a similar card, with the hours
painted underneath, and divided to 20 minutes. G is the hour index. D is
a straight wooden pointer, 12 in. long, having a piece of brass tube, E,
attached, and a small opening at J, into which is fixed the point of a
common pin by which to set the pointer in declination. H is a nut to
clamp pointer in position. By this simple toy affair I have often picked
up the planet Venus at midday when visible to the naked eye.--_T.R.
Clapham in English Mechanic_.

[Illustration: A STAR FINDER.]

* * * * *

The best mode of finding or tracing trichinae in pork by means of a
microscope is the following: Cut a very thin longitudinal slice of the
muscle by means of a very sharp knife or razor. Press it between two
glass slips, and examine by transmitted light, The coiled trichinae may
be readily distinguished from the muscle fiber.

* * * * *




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