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be kept for thirty or ninety seconds, rarely longer. It should be 

 frequently removed with the forceps during this period, and held 

 to the light for examination, so that the moment for final removal 

 and putting into benzole be not missed. After a little practice 

 the eye will accurately determine the time for removal. 



Before placing the object in benzole it is well to hold it in the 

 forceps for a few seconds, letting the end touch some clean surface, 

 that the dye may drip off, and the object may become partially 

 dry. By doing this, fewer particles of insoluble dye rise to the 

 surface of the benzole, in which the brushing is done to remove 

 foreign matter. The object should then be put into clean benzole. 

 In this it may be examined under the glass. If it is found that 

 it has been kept in the blue too short a time, it should be 

 thoroughly dried, and, after dipping in alcohol, be returned to that 

 dye. If a section of leaf or other soft tissue be under treatment, 

 it should be put in turpentine or oil of juniper, as they do not 

 contract so much as benzole. 



When hrematoxylon is used instead of magenta, it is followed 

 by the blue as just described. As neither of these dyes comes out 

 in alcohol or in oil of cloves, the section may be kept in the 

 former for a short time before' placing in the latter. 



The haematoxylon dye I prefer is prepared by triturating in a 

 mortar for about ten minutes two drachms of ground Campeaehy 

 wood with one ounce of absolute alcohol, setting it aside for 

 twelve hours, well covered, triturating again and filtering. Ten 

 drops of this are added to forty drops of a solution of alum ; 

 twenty grains to the ounce of water. After one hour the mixture 

 is filtered. 



Into this the section, previously soaked in alum-water, is placed 

 for two or three hours, or until dyed of a moderately dark shade. 

 When dyed of the depth of shade desired, which is determined by 

 dipping it in alum-water, the section is successively washed for a 

 few minutes each, in alum-water, pure water and fifty per cent. 

 * alcohol. Finally it is put in pure alcohol until transferred to the 

 blue. 



Carmine and aniline blue produce marked stainings T but they 

 are rather glaring to the eye under the glass. I use an ammoniacal 

 solution of the former, double the strength of Beale's, substituting 

 water for glycerine. In this a section is kept for several hours. 

 On removal it should be dipped in water, and then put for a few 



