Your’s of the 15th is recieved & I am disconsolate on learning my mistake as to your having a dynamometer. my object being to bring a plough to be made here to the same standard of comparison by which Guillaume’s has been proved, nothing less would be satisfactory than an instrument made by the same standard. I must import one therefore, but how, in the present state of non-intercourse is the difficulty.   I do not know Dr Mason personally, but by character well. he is the most red hot federalist, famous, or rather infamous for the lying & slandering which he vomited from the pulpit, in the political harangues with which he polluted that place. I was honored with much of it. he is a man who can prove every thing if you will take his word for proof. such evidence of Hamilton’s being a republican he may bring: but mr Adams, Edmund Randolph & myself could repeat an explicit declaration of Hamilton’s against which Dr Mason’s proofs would weigh nothing.   I am sorry to learn that your rural occupations impede so much the progress of your much to be desired work. you owe to republicanism, and indeed to the future hopes of man, a faithful record of the march of this government, which may encourage the oppressed to go & do so likewise. your talents, your principles, & your means of access to public & private sources of information, with the leisure which is at your command, point you out as the person who is to do this act of justice to those who believe in the improvability of the condition of man, & who have acted on that belief, in opposition to those who consider man as a beast of burthen made to be rode by him who has genius enough to get a bridle into his mouth.  the dissensions between two members of the cabinet are to be lamented. but why should these force mr Gallatin to withdraw? they cannot be greater than between Hamilton & myself, & yet we served together 4. years in that way. we had indeed no personal dissensions. each of us perhaps thought well of the other as a man. but as politicians it was impossible for two men to be of more opposite principles. the method of separate consultation, practised sometimes in the cabinet, prevents disagreeable collisions.

You ask my opinion of Maine. I think him a most excellent man. sober, industrious, intelligent & conscientious. but, in the difficulty of changing a Nursery establishment, I suspect you will find an insurmountable obstacle to his removal. present me respectfully to mrs Barlow, & be assured of my constant & affectionate esteem.

Th: Jefferson