what caused the great fire of london to stop
The strong east wind dropped, and the Tower of London garrison used gunpowder to create effective firebreaks, halting further spread eastward.
Great Fire of London
 The battle to put out the fire is considered to have been won by two key factors: the strong east wind dropped, and the Tower of London garrison used gunpowder to create effective firebreaks, halting further spread eastward.

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Great Fire of London [SEP] Introduction
A melted piece of pottery on display at the Museum of London found by archaeologists in Pudding Lane, where the fire started, shows that the temperature reached . The social and economic problems created by the disaster were overwhelming. Flight from London and settlement elsewhere were strongly encouraged by Charles II, who feared a London rebellion amongst the dispossessed refugees. Various schemes for rebuilding the City were proposed, some of them very radical. After the fire, London was reconstructed on essentially the same medieval street plan which still exists today.