280 INJECTIONS. 



only. Add this to the shellac solution and strain through 

 muslin. For very minute injections dilute the mixture with 

 alcohol, filter through filter-paper on a covered funnel, and 

 evaporate down to the desired consistency. Common moist 

 water-colours, such as are sold in tin tubes, may be employed ; 

 they are to be well washed through several changes of water 

 "to get rid of the medium with which the pigments are mixed, 

 and then suspended in alcohol as above directed. (These are 

 to be recommended for injections into the blood of living 

 animals.) 



The shellac solution is not attacked by hydrochloric acid ; 

 hence its applicability to corrosion preparations. To correct 

 the brittleness of the corroded mass it is well to add to the 

 injection-fluid some 5 per cent, of a filtered alcoholic solution 

 of Venetian turpentine. This may also be of use for prepara- 

 tions that are not to be corroded. For corrosion, concen- 

 trated (fuming) hydrochloric acid may be used, and small 

 objects left in it for one day, large ones many days or even 

 weeks. 



For hardening injections, of which it is desired to cut 

 sections, chromic acid may be used, or a mixture of chromic 

 and hydrochloric acid (1 part of each to 250 500 parts water) . 

 Sections are best mounted in glycerin. 



This method, with some slight modifications of detail, has 

 lately been recommended by BELLAEMINOW (Anat. Anz., 1888, 

 p. 650 ; see also Zeit. f. wiss. Mik., v, 4, 1888, p. 523, and 

 Journ. Roy. Mic. Soc., 1889, p. 150). 



517. Hoyer's Oil-colour Masses (Internal. Monatschr.f. Anat., 

 1887, p. 341; see also Zeit. f. wiss. Milt., 1888, p. 80, and 

 Journ. Roy. Mic. Soc., 1888, p. 848). 5 grms. artist's Berlin 

 blue oil-colour are rubbed up with 5 grms. thickened linseed 

 oil, and mixed with about BO grms. of lavender oil, fennel oil, 

 thyme oil, or rosemary oil, allowed to stand for twenty-four 

 hours in a well- stoppered vessel, and decanted. Shake before 

 using. 



For injection of the vessels of the spleen and other difficult 

 objects. 



Good results were also obtained with chrome-yellow oil- 

 colour. 



