718 



SCIENCE 



[N. S. Vol. XXVI. No. 673 



series of tests, in what lie could call a per- 

 fected form, he did wish to present for the 

 consideration of the members certain phases 

 of the work, which had been done. 



The principal color-destroying or changing 

 agencies toward which the fastness of dyestuffs 

 are usually tested may be enumerated as fol- 

 lows : Fastness to light, fastness to weather, 

 fastness to washing, fastness to scouring, fast- 

 ness to milling (including felting and fulling), 

 fastness to alkalies, fastness to acids, fastness 

 to chlorine, fastness to sulphur dioxide, fast- 

 ness to rubbing, fastness to ironing and 

 calendering, fastness to steaming, fastness to 

 perspiration, fastness to urine. 



The paper then went into detail concerning 

 the methods of determining the fastness of 

 dyestuffs to the above agencies, and also the 

 methods of recording the same. To make the 

 record of a color complete, certain other data 

 were also recorded namely: Its name, dyestufi 

 concern manufactiiring or selling, samples of 

 the textile material dyed full shade, and in 

 various percentages to indicate its coloring 

 value, a detailed recipe of the process used in 

 making the dyeings that are tested, its solu- 

 bility, color of its solution, action of its solu- 

 tion with acids, action of its solution with 

 alkalies, and finally three samples of dyed 

 cotton and wool union material to indicate its 

 affinity for the two important fibers, and to 

 give some idea as to its value for union dye- 

 ing. 



The paper was accompanied by many dyed 

 and tested samples which indicated the manner 

 in which all of the above tests and determina- 

 tions of an individual color could be easily 

 recorded upon a single folder of the proper 

 size for an ordinary letter file. 



In conclusion, it was said that the tests de- 

 scribed had been formulated with the constant 

 aim to make them as comparable as possible 

 with the actual conditions of practise, and 

 that they had been revised each time that it 

 was thought that any change would make 

 them approach nearer to this desired condi- 

 tion. In the opinion of the speaker they were 

 subject to still further change and modifica- 

 tion, but as he looked back to the series of 

 tests made four and five years ago, he felt that 



great improvement had been made. He was 

 inclined to believe that all of the members 

 present, who were directly interested in textile 

 coloring, would agree with him that great ad- 

 vances could be made if color dealers and 

 textile manufacturers in general would agree 

 upon certain standards of fastness, and adopt 

 uniform methods for making the various 

 tests which, at the present time, are often so 

 valueless, because of lack of information as to 

 how they were made. 



Much could be accomplished by cooperation, 

 and it was sincerely hoped that the future 

 would see an organized effort, upon the part 

 of those interested, toward the establishment 

 of such methods. 



The paper was discussed at some length by 

 members and guests. At the close of the 

 meeting a vote of thanks was passed, to the 

 Lowell members of the section for the enjoy- 

 able and instructive program and visits of the 

 afternoon and evening, and to the managers 

 of the several industrial plants where visits 

 were made, for their courtesy and attention to 

 the comfort and enjoyableness of the visits. 



Preceding the meeting the members of the 

 section were provided with a tempting lunch 

 at the Lowell Textile School, after which the 

 various departments of the school were visited 

 and the students observed at their work. At 

 2 :30 P.M. parties were formed to visit (a) the 

 Bigelow Carpet Works, (6) the Lawrence 

 Hosiery Mill; (c) the Lowell Gas Light Com- 

 pany, (d) the Merrimack Print Works. At 

 all of these industrial plants the members were 

 shown many interesting and instructive 

 processes. Prank H. Thorp, 



Secretary 



DISCUSSION AND CORRESPONDENCE 



THE EFFECTIVE SUEPAOE-TEMPERATURE OF THE 



SUN AND THE ABSOLUTE TEMPERATURE 



OP SPACE 



To the Editor op Science: I have before 

 me yesterday's issue of Science. As for my- 

 self no more striking illustration could bo 

 given of the chaotic state in which this whole 

 disputed question of the sun's effective sur- 

 face-temperature still remains, than the re- 

 sults obtained by Professor Poynting, as set 



