My dear Sir:

I have received the copy of your excellent work on Coral Reefs, which you kindly addressed to me, and I thank you much for it.—¹ From what you state in your Preface I perceive that I have misunderstood your view on one point (that referred to on p. 320 of my work), and if my work passes to a Second edition, I will have a correction made.—² I observe that you quote Mr Couthouy with regard to the characters of some of the islands of the Pacific.³ He made his observations when connected with Wilkes’s Exploring Expedition, and was on board Capt. Wilkes’s vessel, the Vincennes, and the facts will be found more fully & accurately given in Wilkes’s “Narrative” (5 vols. 8vo.).⁴ Your citations with regard to Rose 1^d led me to look into Wilkes’s work; and I there find that the island has a lagoon 6 to 12 fathoms deep, and an entrance to it of 4 fathoms; that it is under water at high tide excepting two small banks, one of them covered by a clump of trees. I did not land at the island, but spent some time on Tutuila and Upolu, of the Samoa group.⁵ If you can find in England copies of the Maps, or the Hydrographic Atlas, published by Wilkes you would be much interested in examining his maps of coral islands & others bordered by reefs in the Pacific.⁶ Wilkes did not believe in your theory of coral islands, and has published in his book a ridiculous theory with regard to them—making them out remnants of a great land after a vast amount of oceanic erosion.⁷ But the results of the surveys by the expedition are valuable.

Thanking you again for your kindness, I am | with the highest esteem | very truly yours | James D. Dana