i actually wanted to suggest a modification in the topic "megommeter. I found the cross-sectional diagram pretty difficult to figure out .. n i had to access other material to do so. i found the diagram in this particular book to be very clear. page no. 86 in (Web-link removed due to its pointing to copyrighted material) i used the explanation from allaboutcircuits, along with the diagram in the above link.. i think it will help out many more students like me to get the basic concepts clear.