Calls to manual exchanges ( where the caller asks the manual exchange operator for the number ) and calls to special service like 0 for Operator or 999 for emergencies do not require any numeric digits.
32.
In the early days of manual exchanges, outlying areas ( eventually called dependent exchanges ) were connected through progressively larger locations ( eventually called group switching centres ) into one of the main cities-Birmingham, Edinburgh, Glasgow, Liverpool, London, and Manchester.
33.
In London there were 73 manual exchanges within of Oxford Circus, of which 20 had CCI ( Coded-Call Indicator ) equipment which displayed the number dialled to the local manual exchange operator, and the rest were to be equipped shortly.
34.
In London there were 73 manual exchanges within of Oxford Circus, of which 20 had CCI ( Coded-Call Indicator ) equipment which displayed the number dialled to the local manual exchange operator, and the rest were to be equipped shortly.
35.
The French telephone system was heavily damaged in World War II, so that by the end of the War only about 140 automatic exchanges ( mostly in Paris and its " banlieues " ) and 228 manual exchanges were fully operational.
36.
Rural party line numbers in manual exchanges were prone to awkward, non-standard numbering schemes like " line 10, two long rings and one short " which were gradually eliminated as the number of parties on a single line was reduced and the manual switchboard replaced by automatic dial equipment.
37.
For calls to manual local exchanges with CCI equipment to display the called number to the operator, the equipment required at the manual exchange and the director equipment holding time can be minimised by using storage equipment at the automatic exchange which holds the number information until manual exchange equipment is available.
38.
For calls to manual local exchanges with CCI equipment to display the called number to the operator, the equipment required at the manual exchange and the director equipment holding time can be minimised by using storage equipment at the automatic exchange which holds the number information until manual exchange equipment is available.
39.
If a manual exchange did not have call indicator equipment but did have a published numeric exchange prefix, incoming calls from automatic exchanges would be prompted manually with " Number, please ? " after the first few digits ( or, in fixed-length store-and-forward systems like the UK director exchanges, the entire number ) had already been dialed.
40.
In cities outside London, it was possible to avoid the installation of Coded-Call Indicator ( CCI ) equipment at manual exchanges by converting to automatic in stages with the issue of a new directory, e . g . converting groups of ( say ) six exchanges at 12-month intervals; this was done in Liverpool, Birmingham, Glasgow and Edinburgh.
