The object here is emotional imagination.
Recorded on the night of 19 May 1942, when BBC engineers visited a wood in Surrey to record nightingales singing. The microphones also picked up the approach of the Bomber Command force heading for Mannheim, a raid by 197 aircraft including Wellingtons, Stirlings, Halifaxes, Hampdens, Lancasters and Manchesters, of which 11 failed to return. At first considered a possible security risk, the evocative recording was subsequently released commercially by HMV, the complete version being featured here. The raid itself inflicted relatively minor damage on Mannheim. Source
It is the juxtaposition of the beauty of the Nightingale’s singing and the imagined fate of the crew of these planes and the recipients of their bombs that stirs the imagination—even now.
It’s also a reminder that the rest of the natural world doesn’t give a damn about human emotions.
You don’t have 6 minutes to listen to the song of a nightingale?
To what effect was that bombing raid?
19/20 May 1942
197 aircraft – 105 Wellingtons, 31 Stirlings, 29 Halifaxes, 15 Hampdens, 13 Lancasters, 4 Manchesters. 11 aircraft – 4 Halifaxes, 4 Stirlings, 3 Wellingtons – lost. 155 aircraft reported hitting Mannheim but most of their bombing photographs showed forests or open country. A concentrated group of about 600 incendiaries in the harbour area on the Rhine burnt out 4 small industrial concerns. Only light damage was caused elsewhere. The only fatal casualties were 2 firemen. Minor Operations: 65 ‘freshmen’ crews to St Nazaire but bombing results were poor, 9 aircraft minelaying off Lorient and near Heligoland, 13 aircraft on leaflet flights to France. 1 Wellington lost on the St Nazaire raid. Total effort for the night: 284 sorties, 12 aircraft (4.2 per cent) lost. Source
On other nights Mannheim wasn’t so fortunate. It was the target of ‘terror bombing’ by the British and Americans, i.e., bombing aimed at civilians, intended to terrorize and demoralize.