To infiltrate a tissue with paraffin, place the specimen in absolute alcohol or chloroform for an hour or two, then transfer to a bath of melted paraffin, at its melting point (about 110° F.), and keep it at this temperature for several hours, so that the paraffin may penetrate to the middle of the tissue. Then remove the specimen from the paraffin and put it into a small chip-box, pour in enough paraffin to cover it, and set aside to cool. When quite cold, make sections as before, with a razor, or fix it into a microtome, with a little melted paraffin. The sections when cut must be placed in turpentine to remove the paraffin, and then into absolute alcohol to remove the turpentine, and finally in distilled water to remove the alcohol, when they may be forthwith stained. It is often found better to stain the tissue in bulk before embedding. In this case the sections will only require the turpentine to dissolve away the paraffin, and may then be mounted in Canada balsam. _Hardening and Preparing Animal Tissues_ for section cutting and microscopical examination.--Fresh tissues are not well suited for microscopical examination, but it is sometimes advisable to observe the appearances of a fresh specimen, especially if it is suspected to contain amaloid bodies or parasites. It will then be necessary to _tease_ out a small portion of the tissue immersed in a weak solution of salt and water by the aid of a pair of fine needles (Fig. 229) and the dissecting microscope (Fig. 230). [Illustration: Fig. 229.--Needles for teasing out Sections.] [Illustration: Fig. 230.--Dissecting Microscope.] The most important point in connection with an instrument of this kind is, that it affords firm and convenient rests for the hands, and should not be raised too high from the table. The stage should either be made of glass, or provided with a glass dish for dissecting under water, or preservative fluid. A pair of aplanatic lenses, mounted on a focussing bar as shown in Fig. 230, will be found the most convenient to work with. Investigations of this nature should be always carried out in the manner described, but preparations of the kind cannot be preserved any length of time, unless properly hardened in spirit or Formalin solution. The method of teasing out under the light of a condensing lens is shown in Fig. 231. [Illustration: Fig. 231.--Method of teasing out Muscular Fibre, &c., in a fluid medium under Condensed Light.]