164 



MR. E. R. WATSON ON 



Table I. — Fastness to Light of Dyeings on Silk. 









No. of days' 













No. of days' 



bright sunshine 



No. of days' 









T^filfioccs rvf 1 



bright sunshine 



required to 



bright sunshine 







Dyeing. 



shade. 



| 



required to 

 produce first 

 sign of fading. 



reduce shade 

 to one-quarter 

 original inten- 



required to 



completely 



bleach. 





Group. 









sity. 









Turmeric, raised with acid 



full 



I 



3 



6 



\ 





,, alum mordant 



full 



I 



3 



6 



I 



Kusum 



full 



I 



3 



11 





I 



Bakam, alum mordant 



medium 



I 



5 



15 





II 



, , alum-soda mordant 



full 



3 



9 



t 





II— III 



,, tannin-iron mordant 



full 



13 



t 



t 





IV 



Palas, without mordant 



light 



5 



22 



28 



} 





,, alum mordant 



medium 



3 



22 



28 



III 



Latkan, Murshidabad process 



full 



2 



8 



t 



1 



II 



,, Nadia process 



full 



2 



8 



t 



Manjista, alum-soda mordant 



medium 



5 



28 



t 



\ 





, , ditto 



full 



9 



t 



t 



J 



/ 



i 



/ 





ditto followed by soaping 











IV 



and raising 



medium 



4 



28 



t 





, , ditto ditto 



full 



8 



t 



t 





Lac, alum mordant 



medium 



4 



28 



t 





III— IV 



,, alum-soda mordant 



full 



2 



9 



t 





II 



Kamala, without mordant 



full 



3 



17 



t 





II— III 



,, alum mordant 



full 



2 



9 



t 



} 



II 



ditto* 



full 



4 



10 



t 



Singhar, without mordant 



full 



2 



9 



t 



1 



II 



,, alum mordant . . , 



full 



2 



9 



t 



i 



Jackwood, alum mordant 



med.-full 



1 



t 



t 





III 



Orange II, 3% 





9 



22 



t 





IV 



Naphthoic Yellow S. , 0-5% 





2 



3 



7 



} 



I 



4% 





2 



7 



14 





Metanil Yellow E., 1% 





-> 







17 



28 



1 





3% 





3 



28 



t 



III 



;i )> 5 /O 





3 



t 



t 





Scarlet RRR.. 3% 





3 



12 



t 





II 



Fast Pink. 5% 





6 



19 



t 





III— IV 



Auramine II, 3% 





1 



8 



20 





I 



Magenta, 0-13% 





1 



4 



12 



\ 



I 



1% 





2 



7 



28 



) 





Safranin, °'4% 





1 



4 



11 



} 



II 



4% 





2 



15 



t 



IV 



Chrvsophenine BB, 3% 



6°/ 



) > u /O 





9 



9 



t 

 t 



t 



t 



} 





Primuline, 2% 





1 





t 





II 



Thiazine Red R, 5% 





8 



29 



t 





IV 



Primuline 8%, treated with soda 





4 



J 9 



t 





III 



,, 8%, developed with 















Phenol 





4 



J 9 



t 





III 



,, 8%, developed with 















P Naphthol 





3 



15 



t 





II— III 



Alizarine (Hurst loc. cit., 31 















appendix) 





t 



t 



t 



1 





IV 



* The whole sample was exposed to sunlight for two days before the tests were started. 

 ■\ More than 30 days. 



