1)68 M. Becquerel on the Disengagement of 



quite new, chiefly found by him near Dunkerrin, in the county 

 of Kerry, where he now resides. 



The shores of Ireland are also rich in marine plants, which 

 are ably described by Mr Harvey in ths above-mentioned work. 

 The late Miss Hutchins of Ballylickey has enabled us to record 

 the many rare and interesting species found by her at Bantry 

 Bay, as has Mr Harvey those of the coast of Clare and other 

 places ; and Miss Ball has very successfully examined the Wa- 

 terford coast near Youghal. To Mr Templeton, the late emi- 

 nent botanist ; Doctor Drummond of Belfast ; and Mr Moore, 

 we are indebted for a knowledge of many rare species of Algae, 

 found by them on the Antrim coast. In conclusion, we may add 

 that it cannot now be said that the botany of Ireland is little 

 known. 



Summary of some new Inquiries concerning the Disengagement 

 of Caloric by Friction. By M. Becquerel, President of 

 the Academy of Sciences for the year 1838.* 



All bodies are regarded as formed by the union of an infi- 

 nite number of molecules or atoms surrounded by heat, which 

 opposes their immediate contact ; all theoretic views concerning 

 the nature of heat being at the same time avoided. When its 

 quantity is increased or diminished, the distance between the 

 atoms becomes alternatively greater or smaller, and the size of 

 the body undergoes correspondent variations. 



It is also admitted that these same atoms are subjected to an 

 attractive power which tends to their mutual approximation, 

 and which, consequently, is opposed to the repulsive action of 

 heat. With these two a third power is finally associated in the 

 constitution of bodies, viz. the attraction of the atoms for the 

 heat, which surrounds the neighbouring atoms. So long as the 

 power of aggregation prevails over the other two, the body con* 

 tinues solid ; if the heat is increased, a time comes when the 

 atoms acquire a certain degree of mobility, and the body be- 

 comes liquid. And, finally, if the quantity of heat becomes so 

 considerable that it quite overcomes the power of aggregation, 

 the body assumes the gaseous form. The atoms of bodies be- 



* Bead to the Academie des Sciences, Aug. 13. 1838. 



