Page 



Too long 26 



Too tall 26 



Volcanoes . . 26 



Side or top valleys or branches . . 26 



No bottom webbing 26 



Average number of demerits characteristic of each type and 



grade of sponge • 27 



Rock Island 27 



Inshore sheepswool 29 



Anclote Grass 30 



Florida Key Wool 30 



Hudson Grass 32 



Mediterranean Bengasi • 32 



Mediterranean Deepwater • 33 



Cuban Sheepswool 33 



Grading standards and prices •• 35 



Quantitative tests 37 



Water test • 37 



Bottom can •• 38 



Middle can 38 



Top can 38 



Measuring board ....*• 39 



Procedure used in water tests 39 



Calculation of water properties Ul 



Water- test conclusions Ul 



Summary of water properties ••• U5 



Field testing U6 



Abrasion or Wear Tests . . . hi 



Procedure • U8 



Abrasion results U9 



Conclusions on abrasion tests ••• U9 



Cleanliness test •• h9 



Density test •••• 51 



Selling by weight • •• 53 



Recommendations for grading standards 5U 



Bibliography • • 58 



