Dr. E. J. Mills's Researches on Melting-point. 



25 



given under /3 mononitrophenol); it was crystallized once from 

 water, once from alcohol, and again from water. 



N was prepared from some a (Hiibner's) dinitrophenol, for 

 which I am indebted to Prof. Armstrong. This was purified 

 by Hiibner's two processes, and can have contained at most 

 mere traces of its isomer. The trinitro-compound was crys- 

 tallized thrice from water. 



Trinitrophenol is a nearly white substance when in crystals; 

 if very finely divided by any means, it appears a pale yellow. 

 The powdered crystals, if exposed for two hours to indirect 

 light on a dull morning, acquire a deep mustard-yellow colour. 

 The crystals of the substance termed N were almost perfectly 

 white. 



The melting-point of trinitrophenol is, on the whole, not 

 difficult to observe. 



Table XXII. 





A. 



Z. 



O v 



2 . 



o, 



M. 



F. 



N. 



N. 

















o 







o 





121-11 



120-95 



121-04 



121-14 



12103 



120-99 



121-20 



121-20 



121-09 





•06 



120-92 



•07 



121-11 



12098 



121-13 



121-17 



120-98 



120-89 





08 



12103 



•01 



12097 



12098 



•10 



120-98 



12109 



121-09 





•11 



120-95 



•15 



121-14 



121-08 



•IS 



121-14 



•12 



120-94 





•03 



121-06 



•18 



12097 



•00 



•10 



•09 



•12 



121-11 





•06 



121-00 



•12 



121-06 



•08 



•16 



•01 



•15 



121-11 





•03 



120-98 



•23 



•14 



•06 



•19 



•12 



•12 



121-14 





•06 



121-20 



•09 



•09 



•14 



•07 



•04 



•12 



12094 





■24 



121-00 



•12 



•09 



•11 



•19 



•14 



•15 



120-99 





120-97 



121-00 



•09 



•11 



•06 



•16 



120-98 



•17 



121-07 





121-07 



12101 



121-11 



121-08 



121 05 



121-13 



121-09 



121-12 



121-04 



Probable error. 



•014 



•016 



•013 



•013 



•on 



•013 



•016 



•012 



•018 



Thermometer ... 



2 



2 



2 



2 



2 



2 



2 



2 



3 



F. Naphthalin Derivatives. 



Naphthalin. — Commercial pure naphthalin, which had been 

 twice sublimed, was digested for a few hours with strong oil 

 of vitriol in the water-bath. After washing with water, it was 

 distilled from caustic soda in a current of steam. The first 

 portion of the distillate is termed A, the second B. These 

 portions were crystallized twice from naphtha and thrice (A 3 

 &c.) from alcohol. Before naphthalin melts it exhibits a de- 

 cided pasty stage; yet the melting-point is sufficiently sharp. 



The powdered substance is highly electric. 



