I return you my best thanks for your politeness & attention to the Essay I did myself the pleasure to send you. Knowing how much you are troubled with correspondents I forebore at that time to obtrude myself upon you—but as you had the politeness to inform me you had read my Essay or Memoir, (to a young author no Small compliment) I beg leave to occupy Your attention a little longer with the consideration of a subject (hinted at in your letter) & which may be considered as Supplimentary to my printed Work.

The Migration of Plants has long engaged my attention—& I have considered it as one of the most perplexing researches that we can with our present degree of knowledge undertake.

All enquiries on this subject must of necessity begin with that time when vegitables first made their appearance on the face of our earth. the Question then will be whether they sprang up at once over the World according to different Climates or whether they first made their appearance in one particular country & from hence were scattered & diffused over the other parts of the earth either by the various means that Nature directly employs or which chance & accident might indirectly effect———This latter opinion is I think untenable because there are various genera & species of plants peculiar to every country of the Globe.—Yet according to the opinion now under consideration—these plants must have vegitated in all the countries between their present climates & the one they1 originally came from—we may therefore enquire what has become of the plants in the intermediate countries where the Seed germinated—the pollen was excreeted & where the stigma style & germen in the fulness of perfection prepared the new plant.—Added to this is the fact that mountains for instance the Andes & the Alps have near their summits the same species of Plants—& which could not bear the high temperatures of the intermediate countries

The first opinion viz That Plants started into vegitation nearly in the climates and sittuations in which they are at present found is more plausible but has nevertheless many difficulties to encounter & has hitherto been deemed by me unsatisfactory in many points—my objection however to this opinion arises from the consideration of annother Subject which perhaps may make you smile when I name The Flood—be so good however to let it pass my belief of that catastrophe is I acknowledge founded upon annother base than either Natural History or Natural Philosophy—I do not know one Single fact in physics that proves the calamity of the Noachic Deluge—but as I credit the narration from other authorities You will be good enough to let me use it

I cannot understand how the vegitable world could have been preserved in the tumultuous2 agitation of an universal deluge deprived of light & heat for an entire year—On the subsidence of the waters it would it appears to me be necessary either to have a new creation—or else a miracle to call forth the suspended functions & powers of a seed or plant which had been steeping in water for a twelvemonth.—This is my great objection—to this opinion & which is a knot I am unable to loose

It was considerations of this kind that determined me not to introduce Botany in my Researches—I had no conviction of the Subject in its first stage—And it was not from want of candor but through remissness that I did not mention the intractable state of this part of the Question—If I could have settled this part—the application to the condition of Islands would have been forcible.

I am unwilling to engage any more of your time by writing further upon this Subject—I return you my best thanks for the politeness you have shewn me & conclude with wishing you every happiness that your long & unwearied Services for the good of our country So well entitle you to.