Mr. Madison has received Mr. Custis’s note of the 30th ultimo, with the specimen of fine wool accompanying it. He offers for himself the thanks to which Mr. Custis is entitled, from all his fellow-citizens, for his laudable and encouraging efforts to increase and improve an animal which contributes a material so precious to the independent comfort and prosperity of our country. Mr. Madison wishes that Mr. Custis may be amply gratified in the success of his improving experiments, and that his patriotic example may find as many followers as it merits.