220 CONNECTIVE TISSUE. 



sition from cartilage and periosteum. Lieberktihn, * on the contrary, fully 

 corroborated the old and well-established views of an apposition. Recently, 

 again, Strelzofft favored the view of an interstitial growth, and was con- 

 tradicted by Steudener, t who demonstrated that the bone-corpuscles with 

 advancing age decrease somewhat in size, and consequently appear to become 

 farther apart as the bulk of the basis-substance increases. 



V. Ebner has arrived at the conclusion, based on macerations of bone in a 

 ten to fifteen per cent, solution of chloride of sodium, to which he added one to 

 three per cent, muriatic acid, that the lamellae of bone-tissue are composed of 

 fibrillse. These fibers, according to him, can be isolated only for short distances, 

 as they are interwoven and held together by a cement-substance containing the 

 lime-salts, while the fibrillse themselves are glue-yielding, but destitute of 

 lime-salts. Fibers running from a lamella to the surface of the bone consti- 

 tute the perforating fibers of Sharpey. 



C. Langer || added valuable contributions to the knowledge of the distribu- 

 tion of blood-vessels in shaft and flat bones. 



M. Kassowitz If published an extensive article on the formation of bone, 

 with special reference to the periosteal cartilage. 



Methods. It is one of the strangest facts in histology that, 

 although for a number of years dry specimens of tissue have been 

 acknowledged to be worthless for microscopical research, bone 

 even in our day is studied in the dry condition. All books of all 

 nations on histology give accurate directions for slicing dry bone 

 and grinding the sections thin for mounting in Canada-balsam. 

 Such specimens are of little value for examinations with the 

 microscope. Specimens of dry bone are about as useful for 

 obtaining histological facts as are the silver- stained specimens of 

 other tissues i. e., both exhibit the frame of the tissue, while 

 all the soft parts, the real seats of life, are destroyed. 



There is but one way to render bone-tissue suitable for study, 

 and that is by softening fresh bone in a one-half per cent, solution 

 of chromic acid, to which from time to time very small quantities 

 of dilute hydrochloric acid may be added. If the chromic acid 

 solution be changed every fourth or fifth day, and if a large quan- 

 tity of the liquid be used for small pieces of bone, in a few weeks 

 the specimens can be easily cut with the razor. This method 

 was introduced by H. Miiller in 1858, but has been far too much 



* Sitzungsb. d. Marburger Gesellsch., 1872. 



I Untersuchungeu aus dem Pathol. Inst. zu Zurich, 1873. 



f'Beitrftge zur Lehre von d. Knochenentwicklung." Abh. der Naturf. Ges. zu Halle, 

 1875. 



" Ueber den feincren Bau der Knochensubstanz." Sitzungsber. d. Wiener Akad. d. 

 Wissensch., 1875. 



|| " Ueber das Geiass-System der Kohrenknochen." Denkschrif tender Wiener Akademie 

 d. Wissensch., 1875. " Ueber die Blutgefftsse der Knochen des Schftileldaches." Denkschrif. 

 ten d. Wiener Akademie der Wissensch., 1877. 



U " Die Normale Ossification," etc. Wiener Mediz. Jahrbiicher, 1879. 



