My dear Johnson

I am much obliged for y^r letter & very kind invitation; but I am sorry to say that the exertion of coming to Shrewsbury w^d be far beyond my strength.¹ I am particularly obliged to you for being willing to go to Wroxeter; for the observations will be difficult to make, & you may not succeed in finding sim〈ple〉 sections.² I send by this p〈ost〉 my old paper, which will shew you a little what I am after. Now I have succeeded in ascertaining the exact weight annually cast up by earth worms over a square yard: it amounts to 16 $\frac{1}{10}$ tons of dry earth per acre.³

I thank you for telling me your family news & I wish it was in my 〈$\frac{1}{2}$ page missing〉

P.S. We are reading Miss Meteyard, but find it full of inacuracies & lament that she obtained letters never meant to be published.⁴