Thirty years is more than a lifetime for some people and outside the memory span of others.

Many of you may have little or no idea about Britain's industrial past and the industries that made this country great. One of those industries was coal mining.

Here's a little something to store away for your next pub quiz/trivial pursuit evening: thirty years ago today on 30 December 1986 Coal Mine Canaries were made redundant.

These latest coal industry redundancies were seen by some as another blow by the Thatcher government against British mine workers; the birds were to be replaced by 'new technology.'

The removal of the canaries ended a mining tradition in Britain dating back to 1911, since when two canaries had been employed by each working pit.

New electronic detectors replaced the birds because they were said to be cheaper and more effective in indicating the presence of pollutants in the air otherwise unnoticed by miners.

Canaries were not the only animals which were used to detect the presence of dangerous gases underground, mice were employed too.

Tests conducted by the Bureau of Mines showed canaries were favoured because their reaction to carbon monoxide was more apparent even if small quantities of the gas were present.

The coal mining industry was going through massive changes in the mid 1980s and was very much in decline.

A year-long strike by the National Union of Miners had ended in defeat 1985 and coal miners had lost most of their bargaining power as a result.

Miners are said to be saddened by the latest set of redundancies in their industry but do not intend to dispute the decision.

The on-going effects of the pit closures, redundancies and the resulting miner's strike can still be felt in some areas of the country today.

In the 1940s there had been 718,000 mine workers in the UK; that figure has currently reduced to something less than 10,000.