GRADING STANDARDS AND PRICES 



A study of sponge prices during the fall of 19^5 shewed that the 

 increase in price with size followed a fairly straight line for each 

 •type and grade of sponge, as is idealized in figure 9 on page l£. 

 Since a sponge contains marketable material proportional to its vol- 

 ume, it might be expected that the price 7/ould increase as the third 

 power of the diameter. There was a slight upward curvature with in- 

 creased diameter for some grades, but in general, it appeared that 

 larger sizes must be increasingly difficult to sell, for the sponges 

 were sold proportional to the first power of the diameter rather than 

 to the third power. The relationship between the weight of the Rock 

 Island Sheepswool sponge — expressed as the n umb er of sponges per pound 

 — and the diameter of the sponge is given in table 12, 



If it were not for the cost of the labor, it would appear to be 

 advantageous to make Cuts of the larger sizes, since the smallest 

 size — U-l/2 to 5 inches — appears to bring a premium price. Although 

 the demand may be larger for the small sponges, the trade hesitates 

 to handle them because collection or possession of any uncleaned sponge 

 less than 5 inches in diameter is illegal. Fear has been expressed 

 that it may not be generally known that there is appreciable shrinkage 

 between the size of the live sponge and the size of the resulting 

 cleaned sponge. 



Using the slope of the lines obtained as in figure 9, one finds 

 that each type and grade of sponge bears a definite ratio by price 

 to the other sponges of corresponding size. For instance, Florida 

 Yellow No. 1 Forms sell at about half the price of the corresponding 

 Rock Island Sheepswool sponge, 



Tftlhen a particular grade of sponge is in short supply, there is 

 a tendency to broaden the grading range by including grades both above 

 and below. The average value — in this case, the average number of 

 demerits — is still slose, however, to the previous one. This ten- 

 dency is entirely different from the one shown when all sponges were 

 scarce during the last war, which was to raise prices and to lower 

 grades. The present system of demerits, employing dimensionless units 

 as it does, would forestall such a trend. 



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