THE PROPER TISSUE OF THE CORNEA ; CORNEAL TUBES. 409 



this is accomplished by capillary action, as was maintained 

 by v. Wittich* for the formerly admitted intracellular cavities 

 of the corneal plexus, requires, in consequence of the modified 

 views now held, fresh investigation. 



The ordinary result of all puncture injections is a rupture of 

 the corneal tissue. These rupture experiments present quite a 

 peculiar distribution of the injected material, in consequence 

 of the regular, but not in all directions equally firm, connection 

 of the fibrous mass constituting the cornea. As a result of this, 

 a series of elongated straight tubular canals (the corneal tubes of 

 Bowman, f intercellular spaces of Henle), J or a plexiform system 

 of tubes, has been considered to be present in the fresh cornea. 



In opposition to the numerous and comprehensive statements 

 made by these authors respecting the injectable spaces of the 

 cornea, it may perhaps be considered that our observations are 

 too concise. This is due, however, to the circumstance that what 

 we are treating of is in reality a very simple matter ; the diffi- 

 culties of the subject have been artificially created, first, through 

 the scarcely conceivable attempt to bring the tubular or pexiform 

 splitting of the cornea into relation with the serous canals (corneal 

 cavities); and secondly, through the perfectly legitimate en- 

 deavours to demonstrate lymph spaces in the cornea similar to 

 those which may be so successfully brought into view in other 

 tissues by simple puncture injections. 



Various kinds of injection may be applied for the purpose of 

 splitting the cornea. Those with mercury (Bowman) or oily 

 materials succeed better than those with substances in solution 

 or suspended in water (v. Recklinghausen, Leber). The most 

 advantageous one consists of equal quantities of turpentine and 

 olive oil, the latter being coloured with sethereal extract of 

 alkanet. This material should first be employed, and we may 

 readily satisfy ourselves that other modes of injection lead to 

 the same results. 



* Virchow's Archiv, Band ix. , pp. 90 and 91. 

 t Loc. cit. 



I Loc. cit., p. 592, fig. 448. 



v. Recklinghausen, loc. cit. C. F. Mtiller, loc. cit. Schweigger- 

 Seidel, Loc. cit. 



