Having his left in that town, and his right on a wood, the general conceived his position to be too favourable for speedy abandonment, and on the 26th of December expected the onset of Lannes, Davoust, and the imperial guard of France.
They charged with their usual impetuosity, and drove the Russian right wing, under General Barclay de Tolly, out of the wood; but Bennigsen skilfully availed himself of this occurrence; by his orders Barclay de Tolly retired much further than was necessary for his own safety, and the French, advancing unguardedly, found themselves confronted on very unfavourable ground with the Russian main body, which had now been arranged on a new line of battle, and of a battery of 120 guns, placed so as to command their march with terrible efficacy.

The result was that the Russians lost 5000 in killed and wounded, the French 8000--one of their wounded being Marshal Lannes himself; and the French drew back from the hardly contested field with such haste, that all next day the advancing Cossacks sought in vain for their rear-guard.

On the same day, and with nearly as much success, Prince Galitzin halted also, and awaited and repelled his pursuers at Golymin; and had either Bennigsen or Galitzin been supported by the other divisions which were doing nothing within a few miles of their respective marches, these events might have been improved so as to involve the French army in great and immediate perplexity.

But in truth, the total want of plan and combination on the part of Kaminskoy was by this time apparent to the veriest tyro in his camp.

Symptoms of actual insanity appeared shortly afterwards, and the chief command was transferred, with universal approbation, to Bennigsen.
The affairs of Pultusk and Golymin, however, were productive of excellent effects.