82 Modern Microscopy. 



the excess of medium with some water and a camel's hair 

 brush, dry the slide with a soft rag, put it in a turn-table, 

 and run on a ring of cement. 



Portions of the tongue, trachea and intestine of a rabbit 

 or cat may be treated in the same way. 



Teasing out Tissues. Striped Muscle. Harden small 

 pieces of muscle of a pig in a 2 per cent, solution of bichro- 

 mate of potash for three weeks, then transfer to methylated 

 spirit, in which it may remain until required. Soak a piece 

 in water to remove the spirit, place a very small fragment 

 on a slide in a few drops of water, and with a couple of 

 needles tease or tear the tissue up so as to separate the 

 fibres. Drain away the excess of water, apply a drop or two 

 of Farrant's medium and a cover-glass. 



Fibrous Tissue. Proceed as above. 



Yelloiv Elastic Tissue. Place small pieces of the liga- 

 mentum nuchae of an ox in chromic acid and spirit for ten 

 days. Then proceed as above. 



Nerve Fibres. Dissect out the sciatic nerve of a frog, and 

 stretch it on a small piece of wood as follows : Take a 

 match, make a slit in each end of it, into which put the 

 ends of the nerve ; now place it in a 1 per cent, solution of 

 osmic acid for an hour or two. Wash in water, tease up a 

 small fragment on a slide, and apply a few drops of Far- 

 rant's medium and a cover-glass. 



Non-striped Muscle. Harden a piece of the intestine of a 

 rabbit in chromic acid and spirit for ten days. Wash in 

 water, strip off a thin layer of the muscular coats, and stain 

 it in hsematoxylin. Wash in distilled water, and then soak 

 in ordinary tap-water until the colour becomes blue. Clean 

 a slide, place a small fragment of the muscle on it in a few 

 drops of water, and with needles separate the fibres. Drain 

 off the excess of water, apply a few drops of Farrant's 

 medium and a cover-glass. 



Farrant's Medium. Take of glycerine and a saturated 

 solution of arsenious acid equal parts, and mix them well 

 together ; then add as much powdered gum arabic as the 



