METHOD OF GELATINE (EDEMA. 77 



The time of immersing the sections varies of course 

 with the strength of the fluid, but this should not 

 be too highly colored, and it can be then seen with- 

 out much difficulty when the sections are sufficiently 

 stained. They are subsequently placed in water for 

 a minute or two to remove the excess of magenta 

 prior to transferring them to a slide. A drop of 

 glycerine is now added and the cover-glass laid on, 

 after which the slide is gently warmed over a small 

 flame or otherwise until the gelatine in the sections 

 just melts so as to allow the cover-glass, which was 

 probably tilted up somewhat owing to the thickness 

 of the sections, to settle down. The specimen may 

 then be examined, and if satisfactory, may be pre- 

 served, the preparation being completed after a day 

 or two by fixing the edges of the cover-glass with 

 chloroform balsam. 



By the modes of preparing connective tissue already 

 described the bundles of white fibres, the elastic fibres, 

 and the corpuscles are brought under observation, and 

 it would seem at first sight that these of themselves 

 entirely constitute the tissue. But in considering the 

 nature of the films obtained that they are, namely, con- 

 tinuous over a greater or less area it is clear that the 

 presence of fibres and cells is not alone sufficient to 

 account for the lamina? which are spread upon the slide. 

 And, indeed, by closely observing the preparation it will 

 be apparent that there is pellucid substance uniting every- 

 thing together, through which the fibres run, and in which 

 the corpuscles lie embedded. There is, it is true, a diffi- 

 culty in making this out in most parts, in consequence 

 of its extreme clearness, and the fact that its refractive 

 index is little different from that of the watery fluid the 

 tissue is examined in ; moreover, in the logwood pre- 

 parations the intermediate substance remains entirely 

 unstained. Nevertheless, towards the edge of the pre- 

 paration, where a comparison can the better be made 

 with the surrounding fluid, the fact that such a clear 

 intermediate substance does really exist will be suffi- 

 ciently evident ; and the more so if the cover-glass be 

 slightl}' moved or one edge be gentlv pressed down with 



7* 



