Figure 32. — Photomicrographs of gravel-tempered sherds enlarged twice natural size, showing cross- 

 sectional fractures. Top left, pan sherd from Jamestown (Colonial National Historical Park); top 

 right, pan sherd from Angelica Knoll site, Calvert County, Maryland (United States National Museum); 

 and oven sherd from Bideford (United States National Museum). 



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BULLETIN 225: CONTRIBUTIONS FROM THE MUSEUM OF HISTORY AND TECHNOLOGY 



