3o8 NATIONAL ACADEMY OF SCIENCES 



fiber, others with 8o or 85 per cent., and that some of the contaminations are 

 soluble in cold water, others requiring hot water and soap, or other chemicals, and 

 still others, mechanical, and requiring special machinery for their removal. 



" From all this it will be seen that any classification of wools for tariff, founded 

 on any of the physical characters named, or on the alleged treatment, as 

 ' unwashed,' ' washed,' or ' scoured,' must of necessity be entirely arbitrary, and in 

 very many cases uncertain and unsatisfactory, since each character is variable in 

 itself, and by its combinations allows of an infinite number of gradings and sorts, 

 so that, hoviever classified, according to these characters there will be many 

 samples which will lie so near the assumed border lines that their actual place will 

 be a matter of opinion rather than of demonstration. 



" A classification may, however, be founded on chemical characters determined 

 by the amount of actual wool fiber, which may be used as the fixed quantity for 

 rating a specific tariff. The actual wool fiber may be readily and accurately 

 determined by chemical methods, beyond any reasonable question. 



" Inasmuch as the commercial values depend greatly on the fineness of the 

 wools, and any tariff classification founded on the weight of actual wool substance 

 would bear most heavily on the coarser and cheaper sorts, the ad valorem element 

 may be combined with the fixed element suggested, in order to meet any special 

 ends other than that of mere revenue." "'' 



Up to the present time, Congress has not adopted the sug- 

 gestion of the committee in regard to the classification of wools, 

 but has continued to impose special rates on " washed " wool and 

 " scoured " wool. 



COMMITTEE ON QUARTZ PLATES USED IN SACCHARI METERS 

 FOR SUGAR DETERMINATIONS. 1887 



After the polariscope method had been used for some years by 

 the Government in determining the saccharine strength of sugars 

 on which customs duties were levied, the Treasury Department 

 appealed to the Academy to test certain quartz plates used in the 

 saccharimeters. The following letter was addressed to the 

 Academy by the Secretary of the Treasury, C. S. Fairchild: 



" Treasury Department, 



"Washington, D. C, June 17, 1887. 

 " Gentlemen : Certain questions connected with the classification of imported 

 sugars are now under consideration by this Department. It becomes necessary 

 that three standard quartz plates used by appraisers in determining the saccharine 



"'Rep. Nat. Acad. Sci. for 1885, p. 99. 



