To John Adams from Adam Gerard Mappa, 30 December 1801
Oldenbarneveld, December 30th 1801
Sir!
Mr. van der Kemp communicating to me your desire of committing to writing a description of the Phenomena Which I Saw floating on the Surface of the African & Asiatic Seas, commonly call’d and known by the name of Portuguese Men of war, I do cheerfully undertake,—unhappily I am not Sufficiently informed of the variety and species of foam, to be found in those Regions, which undoubtedly are very numerous, and well worth the researches and attention of naturalists.
It was accidentally that I saw one of these Nautilus on deck, being drawn by a bucket when our Sailors Scrubbed the vessel, (which is often the case when near or under the Equator.) The poor Nautilus was very much bruised, however the touch had the same effect as you did observe on your passage, in 1788, and a Swelling of the part touched was the consequence, which afterwards produced red pustules like measles.
The innumerable Millions which are constantly found near and under the Equator, where Calms generally prevails, likewise in the latitude of the trade winds shows, that the Nautilus is a fair weather Sailor, and delights to Swim or Sail where the least Storms oblige him to dive for Security.
Your observations that each of them had a shell fish growing in the center of their gristle, and of different Species, Suggested with propriety the Idea of a floating power of the spat or Eggs, of the various species of shellfish, which being inbodied or enclosed by slimy and glutinous Substance, receives the power of being carried in, and over the Surface of the Ocean to incalculable distances, whereby probably the different Species have become common to different parts of the Globe,—thus preserved in their weak and defenseless situation till, when quitting their protecting abodes, Serve undoubtedly as a nourishment to voracious fishes, or in being cast on rocky banks or shores, attach themselves by their Spinning power on those rocks to propagate again.
Perusing my dutch Dictionary of Arts & Sciences, compiled by Egbert Buis, counselor of his Polish, and Prussian Majesties, printed at Amsterdam in the year 1775, I found the description of two sorts of Nautilus, the one call’d Nautilus Pompilus, the other Nautilus Papiraceus—of this last, the author relates, that when divided in two parts, (cutting it length way) it discovers a number of cells or cavities, Sometimes to 40 in number connected together by a trunk or hollow pipe, growing in diminution towards the Centre—It is through this tube or pipe that the animal passes its tail or hind parts, with which it is firmly connected to its shell; which he never quits.—this tube appears to be formed by joints in a growing or progressive Succession, as is also the shell and its Cavities, in proportion to the growth of the occupant. These Cavities or divisions are Smooth, and not sharp pointed like the ammons horns.
When the Ocean is calm, then does the Nautilus appear on the Surface, throwing out or Spitting a glutinous Substance which serves him as a sail, at the Same time Stretching out two Arms, or Oars, to row, and advance, or move in any direction. As soon this Nautilus wants to dive, his Sail is lowered, his Oars draw in, and filling his little bark with water to promote his diving power, he Sinks to the deep.—In order to let in the water the fish draws his body with a contracting power close down to the bottom of his shell, giving thereby room to the pressure of the water which soon fills the cavities and promote its Sinking weight,—If the Nautilus wants to rise again he stretches his body into the Cavities, forces out the water, whereby lightening his bark, Soon appears on the Surface.—thus far the Author.
If the observations Concerning this Sagacious Nautilus are correct, how much reason have we not, to adore the Maker of these Wonders of the Deep, who created an insignificant animal with Electric powers, admired, feared, and despised by Man, and with such feeble defence that to avoid the danger of being shipwrecked by Storms and violent waves, he dives, and diving, is perhaps the prey of his Ennemies.
Your observation when at Cowes on the Isle of Wight, that Boats from Colchester were daily employed in collecting this spat, to be deposited on the oyster grounds of that place, is similar to what takes place in the province of Zeeland, where every Spring Several vessels called [Zeidsche Bommen], Send out to the Same Island for that purpose, return with their Cargo of Spat, to be deposited in the Oyster pits in Said province, which in November have their full growth, and are preferred above any kind of oysters in Holland.
In the Year 1772, my Lot cast me to be garrisonned in the Small fortified Town of Axel, Situated on a branch of the Hont or western Schelde.—This having communication with the North Sea, I saw a number of flatt Boats in the latter part of April along the dike at low water mark, throwing out the spat of Muscles, being in clusters, Stringed together by a tough thread, very difficult to break.—Which Muscles did remain on that ground till the latter end of october, and middle of November, when, having their full growth were taken up, and carried to markett. The fishermen informed me that they fetched this Muscle Spat, all along the Coast of Zeeland, from Sand Banks interspersed with Stone rifts.—On these rifts did grow a Sea weed, of a tough and Strong Substance on which the Muscle fastening it self as well as on the rocks, and stones found shelter and nourishment; these weeds abounding with Small crabs and shrimps, furnish the shell tribe with abundant Support.
From the observations of both kinds of Spat, it is evident that the large Stock of their progenies does not float upon the Surface of the ocean, but Seemingly remain upon the Spot where the greatest quantity, are every hatched, and gathered for the above mentioned purposes,—as evident however it is that of the great mass of preparatory matter for shell fish, thrown out by the Oyster and Muscle, a vast quantity, in the first instance does rise and float, which being enclosed by the glutinous Substance as observed, produces the innumerable Millions of that Species of Nautilus, in, I believe every part of the known World.
I observed further that among the number of voracious fishes, who live entirely upon the shell tribe are, the holly bot, Turbot, flounders, and Haddock.—I never recollect a Single instance, when I opened the Stomach of any of these Species or, I found a number of Spat, of every sort in them, particularly the Haddock which Seems to be the most voracious, and of which we have prodigious quantities on the dutch markets, in the months of May and June, being catched on the numerous Banks which surrounds the Holland Coasts.
I hope that my little Stock of Information may be of any Service to your interesting researches, and notwithstanding their Small meritt will be of Some use in promoting that Object.—I have the honor to be with due Respect, / Sir! / Your Obedt. humble Servant.
A: G: Mappa
MHi: Adams Papers.