258 PHILOSOPHICAL TRANSACTIONS. [aNNO 1751. 



and inquiries, and has for its object a part of natural history not hitherto well 

 known. 



The first chapter of the work contains the opinions of the ancients concerning 

 coral, and the observations made on it since their time ; among which are the 

 opinions of Peireskius, Boyle, Piso, Boccone, Venette, the Comte de Marsigli, 

 and those of M. de Peyssonnel himself In the 2d is an examination, whether 

 coral is a plant, or a congelation ; in which are included 1 extracts, one from M. 

 Tournefort's Elements of Botany, and the other from the Memoirs of the Royal 

 Acad, of Sciences. The 3d chapter exhibits new observations, from which are 

 discovered the urticae marinae and purpurae, which form coral ; where likewise are 

 explained the formation and mechanism of this marine production. In the 4th 

 chapter we find new chemical observations on the distillation of coral, which tend 

 to prove that coral is the production of insects.* In the 5th are exhibited the de- 

 finition, etymology, colours, and different sizes of corals, and of the insects 

 inhabiting them. The 6th shows the places where they fish for coral, and the 

 manner of fishing for it. In the 7 th we have the manner of working upon, and 

 of polishing coral, and the commerce with it. The 8th, Qth, and 10th chapters 

 give the chemical preparations of coral, its virtues and uses in medicine, when 

 variously prepared. 



The subjects of the 8 dissertations of the 2d part of this work, are the several 

 species of vermicular tubes found in the sea, the madrepores, millepores, litho- 

 phytes, corallines, sponges, the various shell-fish, which inhabit the sea without 

 changing their place, and the formation and mechanism of these several substances. 



This then is the general scope of our author ; and though every part of his 

 work deserves to be considered, Mr. W. on account of the space usually allowed 

 to works of this nature, confined himself to such parts only, as seemed most to 

 merit the attention of the r. s. 



It had b<'en long the received opinion, that coral was soft in the sea, and was 

 hardened by the air on taking it out of the water ; and the learned Mr. Boyle 

 was not willing to quit this opinion. But as experiments are the only way of 

 assuring ourselves of the truth, Boccone, for this purpose, went to sea in one of 

 the coral-fishers vessels, and by plunging his arm into the water had an oppor- 

 tunity of examining the coral, as they were fishing it up, before it came into the 

 air. He invariably found it hard, except at its extremities ; where, on pressing 

 it between the nails of the fingers, it furnished a small quantity of a milky fluid, 

 resembling in some degree the juice of spurge or sow-thistle. Boccone observes 

 further, that he saw several furrows under the bark of the coral, which terminate 

 at the extremities of the branches, about which one might clearly see several 

 small holes of the form of a star, which he imagines are destined for the produc- 



* Improperly called insects, being the production of worms. 



