LABORATORY SUPPLIES AND CHEMICALS 143 



WHATMAN FILTER PAPERS 

 (British Made) 



All grades are guaranteed free from Starch and Chlorine. 

 All Whatman Circles are put up in sealed boxes, distinctively labeled. 



We offer the following grades of Whatman niters with imported paper equivalents 

 conforming in quality as far as possible: 



2704 FILTER PAPER, Whatman, No. 1 (S. & S. No. 595), a good, light paper, for 



general qualitative use. Free from chlorine, grained surface, 

 round niters. 



Diam. in cms... 4.25 5.5 7 9 11 12.5 15 18.5 24 27 32 38.5 40 50 



Each $0.15 .17 .20 .24 .28 .37 .51 .71 1.25 1.48 2.30 2.76 3.13 4.40 



In sheets 18^4 inches x 22 l / 2 inches, per 100 $ 4.45 



Ditto, per ream 20.25 



2705 FILTER PAPER, Whatman No. 2 (S. & S. No. 597), a qualitative paper similar 



to No. 2704, but stouter, retaining fine precipitates. This is 

 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! $0.27 .34 .42 .52 .74 1.04 1.78 



In sheets 18J4 inches x 22 l / 2 inches, per 100 $ 6.85 



Ditto, per ream 31.10 



2706 FILTER PAPER, Whatman No. 3 (S. & S. No. 598), a very stout filter paper 



for general qualitative work. Slightly slower than No. 2, 

 but very retentive. Will withstand considerable washing. 

 Especially suited for -fine precipitates, such as Metastannic 

 Acid, Calcium Oxalate, and Ammonium Phospho-Molyb- 

 date. Very satisfactory for filtering the solution of a fusion 

 made with Eschka's mixture in determining Sulphur in coal 

 and coke; can also be used in recovering small quantities 

 of Silver in the form of chloride. 



Diameter, cm 7 9 1112.5 1518.5 



Per 100 circles $0.40 .50 .57 .74 1.04 1.46 



In sheets, IS]4 inches x 22 J / 2 inches, per 100 $10.20 



Ditto, per ream 46.40 



