54 Answers to Queries. 
Oil of Anise.—This oil freezes at 50° F., it then makes a most 
beautiful polariscope object. Thaw the oil, place a drop ona 
glass slide and allow it to freeze, which it soon does, then view it 
under a thin glass cover without a selenite. As soon as the oil 
begins to melt again, lovely forms of the brightest and most 
varied colours will be seen in motion in the field, their colours 
ever changing as their position changes with respect to the plane 
of primitive polarisation. 
Cheap Paint.—By mixing very fine coal with linseed oil, you 
can make a paint, the application of which to posts before letting 
them into the earth will preserve them for centuries. 
A good Polish for Furniture.—To polish furniture and pre- 
serve it, a most simple and effectual method is to mix equal 
quantities of vinegar and sweet oil. Well wash the wood with 
warm water and soft soap, and dry it thoroughly ; then apply the 
polish with a piece of flannel, and let it remain on a short time, so 
that the vinegar may sink into any little cracks there may be, and 
kill the insects which frequently hide there, especially if the 
furniture is old. Afterwards, rub with a clean soft cloth. 
Answers to Queries. 
318.—Fish-Skin and Scales.—For the polariscope these should 
be mounted in balsam, but for ordinary purposes it is best to 
mount them in a simple dry cell as opaque objects, as when 
mounted in fluid or balsam they become so very transparent that 
their structure is rendered almost invisible. A ring of varnish 
makes a sufficiently deep cell in most cases, as a little pressure 
only prevents them from curling up. For the skins a deeper. cell 
may be fixed, such as a ring of thin cardboard. I would also 
suggest the use of the tiniest atom of gum tragacanth dissolved in 
water to form a paste, by means of which the scales may be held 
to the slide, and prevented from slipping ; a good background may 
be produced by a patch of asphalt on the under-side of the slide. 
If balsam is used, the scales may be arranged ina group ina 
small drop of balsam on the cover, the latter exposed in a warm 
place (protected from dust), till the balsam is hard, and then 
turned over into a fresh drop of balsam, on a clean slip, without 
displacing the scales ; they may, however, slip slightly out of place 
in the subsequent drying, if the slide be not kept horizontal. The 
prevalent craze for staining has not spared even fish scales, though 
