In this frame of mind he made one of the strongest and best speeches he ever delivered on this topic.

He denied that slavery was an "institution;" he denied that the local right to hold slaves implied the right of the owner to carry them with him and keep them in slavery on free soil; he stated in the strongest possible manner the right of Congress to control slavery or to prohibit it in the territories; and he concluded with a sweeping declaration of his opposition to any extension of slavery or any increase of slave representation.

The Oregon bill finally passed under the pressure of the "Free-Soil" nominations, with a clause inserted in the House, embodying substantially the principles of the Wilmot Proviso.
When Congress adjourned, Mr.Webster returned to Marshfield, where he made the speech on the nomination of General Taylor.

It was a crisis in his life.

At that moment he could have parted with the Whigs and put himself at the head of the constitutional anti-slavery party.