Napoleon crosses the Guadarrama (december 22, 1808)

Villacastin, 23th december 1808
To Joseph Napoléon, King of Spain (El Pardo)

My Brother, I have crossed the Guadarrama with a portion of my guard, and in very unpleasant weather. My guard is to sleep tonight at Villacastin. Marshal Ney is at Medina. It seems that the English are at Valladolid, probably with only a vanguard, and that the rest of their army is in position at Zamora and Benavente. It appears that they have established their line of operations in Corunna.
You will have seen in your instructions that Madrid is your principal object. Ruffin's division ought to have arrived. Order it to be put into the Madrid newspapers that 20,000 English are surrounded and lost. Insert also the annexed letter, which will show the Spaniards how they are treated by their dear allies,
and add some remarks upon those who called the English into Spain, which is thus ravaged both by her enemies and by her friends.
I have ordered that all the unembodied men, the convoys, &c., at Boceguillas, proceed to Segovia, which is becoming the centre of the army's operations.
I conclude that Marshal the Duke of Dantzig will attack tomorrow the enemy's force which is before him, take their guns, and pursue them with the cavalry; when this is done, he may be directed on any other point.
The 2nd regiment of dragoons will had arrived to Madrid. The two battalions of the 55th, which were sent to Guadalajara, require an intelligent commander. If threatened, they may retire on Alcala.
The weather is somewhat cold.
Take care of the post by Las Rozas and Guadarrama, that we may be able to communicate.
This little town has behaved well. Most of the inhabitants have remained.

Taken from
Histoire du Consulat et du Premier Empire - Correspondance de Napoléon 1er
Confidential correspondence of Napoleon Bonaparte and his brother. Vol I. p 884. Appleton and Co., New York, 1856