Allen — The Insulating Properties of Erinoid. 



337 



The results obtained are given in Table 2 ; o- being the specific resistance 

 in megohms per cm. cube ; I the effective length, b the breadth, and t the 

 thickness of the sheet sample in cms. ; and D x and D> the outer and inner 

 diameters of the tubular samples. 



Table 2. 



