From: Campos & Davis Photos (photos@campos-davis.co.uk)
Date: 02/11/00-08:43:34 AM Z
I am a little confused about the history of HYPO.
I know Sir John Hershel discovered fixer by accident when he added
Sodium Thiosulphate to developer in the hope of increasing the action
which in fact delayed it to such an extent that it arrested
development, but why did he think it was Sodium Hyposulphate?
The history books say that Sodium Thiosulphate was misnamed, so was
Hershel adding a substance the he believed was Sodium Hyposulpahte
because Sodium Thiosulpahte did not exist (had not been discovered) or
did he put in the wrong substance by accident and then find out it was
a different substance?
When was it discovered that Sodium Thiosulphate is the real fixing
agent? Did Hershel discover this? Does Sodium Hyposulphate actually
exist?
An help before my presentation about electromagnetic imaging on
Tuesday would be very much appreciated.
Thanks
Richard Davis
Campos & Davis Photos
6 Cranbourne Road
London N10 2BT - UK
Tel: + 44 181 883 8638
Fax: +44 208883 8638
email: photos@campos-davis.co.uk
www.campos-davis.co.uk
This archive was generated by hypermail 2b29 : 04/24/00-04:37:09 PM Z CST