Toroid info wanted

From:  michael tucknott [SMTP:michael.tucknott-at-virgin-dot-net]
Sent:  Sunday, March 15, 1998 11:17 PM
To:  tesla-at-pupman-dot-com
Subject:  Toroid info wanted

Help--can any body tell me why some coils have there toroids standing
off the top.
Also what is the best way of mounting the toride.And is it best to make
it adjustable. 

Cheers Mick(coiling in the UK)Tucknott