Simple Plan of Imbedding Tissues. Bij Br. Bichardson. 475 



pressure for sending it home in the microtome well. If too much 

 paper has been applied, tear off the superfluous portion until the 

 desired calibre is attained. 



The paper when wetted will, of course, stretch, but a little 

 practice soon teaches the operator to roll it with only the tightness 

 necessary for allowing the imbedded tissue to be cut without break. 



In careful hands dozens of perfect sections may be cut in half 

 an hour from very delicate stems | of an inch in diameter, or from 

 the delicate aereai-roots of certain orchids. But I should mention 

 that a pine-apple stem f of an inch in diameter has afforded me 

 most perfect sections when imbedded in the semi-pulped paper. 



Up to the present time (April 1882) the only animal structures 

 I have had leisure to imbed and cut in semi-pulped paper were 

 decalcified human teeth, and a diseased external iliac artery removed 

 from the body of a child, one of whose lower extremities I removed 

 by amputation at the hip in March 1879. 



From the "dentinal cartilage" I obtained several thin and 

 instructive specimens. 



The artery did not bear the knife to my satisfaction, having 

 partially "rotted" from a too prolonged immersion in Miiller's 

 fluid. 



Further experience of pulped paper as an imbedding medium 

 may lead to an extended use of the paper for animal-tissue section- 

 cutting. But I prefer to conclude here, at all events, with a 

 stronger recommendation in favour of pulped paper for supporting 

 vegetable tissues in the well of the microtome under the restric- 

 tions I have mentioned. It is almost superfluous to add that each 

 section should be floated off the knife in water, and that a little of 

 the latter should be carried by the blade to the semi-pulped paper 

 in the well, to maintain it at the requisite degree of saturation for 

 efficient cutting. 



The advantages which I consider the method to possess are : — 

 (1) Facility in application ; (2) almost unlimited application in 

 vegetable section-cutting under the restrictions above mentioned ; 

 (3) rapidity in cutting ; (4) the tissues are equally supported ; 

 (5) cleanliness ; (6) heat not being used, the subsequent staining 

 of sections is more equal. 



