CENTRAL SCIENTIFIC CO., CHICAGO, U. 8. A. 



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WHATMAN FILTER PAPER 



WHATMAN FILTER PAPEES have been developed by Messrs. W. & E. Balston, Ltd., of Eng- 

 land, the manufacturers of the well known Whatman Drawing Paper. Working in consulta- 

 tion with Cross and Bevan, the cellulose experts, they have succeeded in perfecting a complete 

 line of these papers, which have been acknowledged to be equal in quality, finish, and serv- 

 ice to any previously on the market. These papers come packed in well-made carboard boxes, 

 carefully labelled and sealed to prevent handling, each box containing 100 circles. 



The grades listed below offer an assortment from which one may select a paper suitable to any 

 type of precise analytical work. In order to give an idea of the work for which each grade 

 is best suited, we give the number of the Schleicher & Schuell, Dreverhoff or Munktell paper 

 to which it most closely corresponds. 



QUANTITY PRICES. 



By agreement with the manufacturers we are permitted to offer the following discounts upon 

 Whatman Filter Papers when purchased in quantities: 



Upon orders amounting to less than $100.00 list Net. 



Upon orders from $100.00 to $200.00 list 5% 



Upon orders above $200.00 10% 



(Orders may be assorted as to kinds and sizes, but must be placed at one time.) 



5410. FILTER PAPER, Whatman No. 1 (S. & S. No. 595), a high grade rapid filter paper for general 



qualitative work and for filtering ordinary precipitates when the ash weight of the paper is 

 of no consequence. Widely used in Sugar Laboratories and for the filtration of yellow Am- 

 monium Phospho-Molybdate after digestion, in determining phosphorus in fertilizers. 



Diameter, cm 7 9 11 12.5 15 18.5 24 



Ash weight per circle, grams 00046 .00076 .0011 .0016 .0021 .0032 .0054 



Per 100 circles $0.20 .24 38 .37 .51 .71 1.25 



FILTER PAPER, Whatman No. 1 (S. & S. No. 595), same as No. 5410, but in sheets, 46.5 x 57 cm. 



5411. Per 100 sheets 4.45 



5412. Per ream (500 sheets) 20.25 



5414. FILTER PAPER. Whatman No. 2 (S. & S. No. 597), a qualitative paper similar to No. 1, but 

 stouter, retaining fine precipitates. This i? the standard grade for analytical purposes. Widely 

 used in the qualitative analysis of the alkaline earths, and in general where fine precipitates 

 of crystalline nature are to be filtered. Especially applicable to Fertilizer, Cement, Steel, and 

 Ore Analysis. 



Diameter, cm 7 9 11 12.5 15 18.5 24 



Ash weight per circle, grams 0007 .0012 .0018 .0024 .0034 .0052 .0089 



Per 100 circles .27 .34 .42 .52 .74 1.04 1.78 



