CLASSIFICATION OF CLEARING AGENTS. 225 



01. Cubebarum, 



01. Fceniculi. 



01. Millefolii florum. 



Ol. Sassafras. 



Ol. Juniperi. 



01. Menthae crispas. 



01. Lavandulae. 



01. Cumini. 



Ol. Cajeputi. 



01. Cascarillae cortic. 



Ol. Sabinae. 



01. Citri. 



01. Origani vulgaris. 



This, then, for Stieda, is the Index Expurgatorius of clearing 

 media. 



B. The oil-of-cloves group, clearing very rapidly sections 

 that have been dehydrated, and clearing watery sections 

 "somewhat more slowly" and with a certain amount of 

 shrinkage. 



01. Gaultherige. 

 01. Cassias. 

 01. Cinnamomi. 

 01. Anisi stellati. 



Ol. Cardamomi, 

 01. Coriandri. 

 01. Carui. 

 01. Roris marini. 



01. Bergamotti. 



But Stieda found kreasote preferable to any of these. 



He relates that kreasote was suggested to him by a paper 

 of KUTSCHIN, Tiber den Bau des RiickenmarJcs des Neunanges, 

 Kasan, 1863. Kutschin rinsed his sections in water t brought 

 them on to slides, drew off the water by means of blotting- 

 paper, and added a drop of kreasote at the side. When 

 clear, he covered and closed the mounts with a border of 

 dammar. 



Stieda modified this process by mounting in dammar instead 

 of kreasote. 



He then tried experiments to ascertain whether oil of cloves 

 could be applied in the same manner that is, to the clearing 

 of non- dehydrated sections. He found that it could, though 

 its employment requires longer time. Sections brought from 

 water into kreasote clear in a few minutes, whilst in oil of 

 cloves they require from half an hour to an hour or more ; 

 and this slowness of the process exposes them to the risk of 

 shrinkage. 



To the group of good clearing agents should be added 

 cedar-wood oil, sandal-wood oil, carbolic acid. 



NEELSEN and SCHIEFFEEDECKEE (Arch.f. Anat. u. Phys., 1882, 

 p. 206) examined a large series of ethereal oils (prepared by 

 Schimmel and Co., Leipzig), with the object of finding a 



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