228 CLEARING AGENTS. 



346. Cannel Oil. Greatly resembles clove oil, but is in 

 general thinner. An excellent medium, which I particularly 

 recommend. 



347. Oil of Bergamot. SCHIEFFERDECKER (Arch. Anat. u. 

 Phys., 1882 [Anat. Abth.], p. 206) finds that this oil has 

 many good qualities ; it clears 95 per cent, alcohol prepara- 

 tions and celloidin preparations quickly, does not attack anilin 

 colours, but the strong odour is disagreeable ; it is as dear as 

 oil of cloves, twice as dear as oil of origanum, and three times 

 as dear as oil of cedar. He considers its action preferable to 

 that of oil of cloves, but, all things considered, gives the palm 

 to cedar and origanum. I think that this is a very valuable 

 medium, and though I do not agree with Schieiferdecker in 

 thinking its action superior to oil of cloves, I think it should 

 always be kept at hand. 



Bergamot oil is, I believe, the least refractive of these 

 essences, having a lower index than even oil of turpentine. 



SUCHANNEK (Zeit. f. wiss. Mik., vii, 2, 1890, p. 158) says 

 that bleached, colourless bergamot oil will not take up much 

 water, whereas a green oil will take up as much as 10 per 

 cent. 



348. Oil of Origanum (NEELSEN and SCHIEFFERDECKER, Arch. 

 Anat.u.Phys., 1882, p. 204). Price per kilo 15 marks ( = 155.). 

 Thin, light brown colour, odour not too strong, agreeable, 

 does not evaporate too quickly, is not changed by light, is 

 rniscible with chloroform balsam and with castor oil. Ninety- 

 five per cent, alcohol preparations are cleared quickly, and so 

 are celloidin sections, without solution of the celloidin. Anilin 

 colours are somewhat extracted. 



For work with celloidin sections care should be taken to 

 obtain 01. Origani Cretici (" Spanisches Hopfendl"), not 01. 

 Orig. Gallici (v. GIBSON; see Zeit. f. wiss. Mik., iv, 4, 1887, 

 p. 482). Specimens of origanum oil vary greatly in their 

 action on celloidin sections, and care should be taken to 

 obtain a good sample. 



SQUIRE, in his Methods and Formula?, &c., p. 81, says that 

 origanum oil (meaning, doubtless, the commercial product) is 

 nothing but oil of white thyme more or less adulterated, and 

 that the product sold as 01. Origani Cretici is probably oil of 

 marjoram. 



