ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 125 



patented by Professor F. S. BarfF. It is a compound prepared by 

 mixing boracic acid with glycerine. The former is dissolved in tbe 

 latter by tbe aid of beat, tbe solution taking about four or five bours, 

 care being taken, bowever, tbat tbe temperature employed sball not be 

 so excessive as to decompose tbe glycerine. To sucb solution or com- 

 pound a furtber quantity of boracic acid is added from time to time 

 until tbe boracic acid ceases to be dissolved. Tbe compound resulting 

 wben allowed to cool, is solid, and is called by tbe patentee 

 boroglyceride. 



In order to employ tbe compound, a solution is prepared in water, 

 alcobol, or otber suitable solvent, and tbe organic substances to be 

 operated upon, eitber immersed in or impregnated witb sucb solutions. 

 Solutions may be prepared of various degrees of strengtb ; but 

 Professor Barff finds tbat a solution consisting of about one part by 

 weigbt of tbe compound and forty parts by weigbt of water will give 

 good results ; otber proportions may, bowever, be adopted for special 

 purposes. Solutions of tbe compound may be applied to tbe preser- 

 vation of all organic substances eitber animal or vegetable. 



Injection-mass.* — L. Teicbmann injects blood-vessels and lym- 

 pbatic vessels witb a mass wbicb is fluid wben cold ; it is made witb 

 finely powdered materials and linseed-oil varnisb up to tbe consistency 

 of putty, and altered to tbat of boney or syrup as required, by volatile 

 liquids (sucb as etber and carbon disulpbide). Prepared cbalk, 

 zinc wbite, &c., may be used, coloured witb cinnabar, ultramarine, 

 cbrome yellow, &c. Ordinary band-pressure is not powerful enough, 

 so Teicbmann makes use of syringes, sucb as those for injecting gutta- 

 percha, in which tbe piston is impelled by a screw arrangement. 



In this way, even tbe finest and most elaborate ramifications of 

 the vessels may be readily and with certainty filled. The mass soon 

 stiffens, partly owing to transudation, partly to evaporation of the ether, 

 so that it does not ooze from vessels which may be cut through ; it 

 remains soft for a certain time and is as hard as stone when the 

 preparation is finished. The advantages of this method are obvious. 



Imbedding Delicate Organs.-j- — L. Fredericq describes a method 

 by which pieces of tissue or organs, such as brains of small animals, 

 livers, kidneys, &c,, are so thoroughly impregnated witb paraffin tbat 

 they retain a firm consistence, do not shrink up, and keep as well as 

 the best casts of the organs. Tbe tissue or organ is hardened by 

 placing in alcohol, first dilute, then absolute, for several days, is then 

 laid for several days in oil of turpentine, until transparent, when it 

 is transferred to paraffin melted in a water bath, and kept there at 

 a temperature of about 55° C. (it must not exceed 60"), for from two 

 to eight hours, according to the size of the object. It is removed and 

 dried while hot in a current of steam, by blotting-paper or otherwise, 

 and finally allowed to cool. 



* SB. Math. Kl. Krakau. Akad., vii. pp. 108-58. Cf. Jahresber. (Vii-chow 

 and Hirsch) for 1879, p. 2. 



t Gaz. med. de Paris, 1879, No. 4, pp. 45-6. Cf. Jahi'csber. Anat. u. Physiol., 

 viii. p. 12. 



