Please note, this eclipse occurred last year (2015). The site has now been updated for the upcoming Solar eclipse in 2016 which will not be visible from London. 
Solar Eclipse from London 2015

From London, the eclipse did not reach total phase but was visible as a partial solar eclipse. Below were the times of the event

Partial Eclipse Begins: 08:25 GMT
Maximum Eclipse: 09:31 GMT
Partial Eclipse Ends: 10:41 GMT

Below is an illustration of maximum eclipse from London

London Solar Eclipse 2015

From London, the sun was 84% covered by the moon at maximum eclipse. Although this meant that eclipse circumstances were be worlds apart from a total solar eclipse, there was a slight darkening of the sky, however even 16% of sunlight was plenty to lighten up the day. The most  noticeable effects are more likely to be the obscure way that shadows are cast during deep partial solar eclipses. See the eclipse phenomenon page for more info on this