Th: Jefferson returns his thanks to mr Lambert for the pamphlets he has sent him and for the testimony they contain of his respect. he has much confidence in the accuracy with which he has ascertained the geographical position of our capital, and on account of the importance of a just ascertainment of our first meridian, hopes it will be still pursued by himself & others familiar with the practice as well as the theory of the subject. He presents him his salutations & respects.