400 Intelligence and Miscellaneous Articles. 



granite, now rendered basic through the more or less complete 

 absorptiou of diabase-fragments. There has been no diffusion of 

 the basic material thus acquired through this second granite. It 

 is pointed out that this explains the intermingling and interstreaking 

 of the two varieties of granite seen on the coast ; the one porphyritic 

 and crowded with fragments, the other non-porphyritic and devoid 

 of fragments. 



Following this general inti'oduction, the characters of the granite 

 are described in some detail ; then those of the diabase, formerly 

 an ophitic doleiite. Details of structure of the granite in 

 which absorbed basic material is present, and of the diabase into 

 which acid material has permeated, are dealt with: particular 

 attention being directed to the great alteration which the diabase 

 has undergone — this has frequently amounted to a total recon- 

 stitution. In this connexion are noticed the prevalence of biotite 

 as a product of such mixing and reconstitution wheu acid materia] 

 is present in quantity, and the almost entire absence of augite 

 under similar circumstances. In rocks of heterogeneous origin into 

 which the diabase has largely entered, similar features are described ; 

 the presence of nests and veins of acid minerals, the entire loss of 

 ophitic structure, the frequent occurrence of much quartz, and the 

 presence of a mineral believed to be sillimanite. The corrosion and 

 reconstitution of the acid felspars under some circumstances are 

 figured and described ; the early stages of such alterations are 

 touched upon, and a table is given showing the gradual increase in 

 specific gravity with increase of absorbed material. 



In conclusion, points of resemblance and of difference are noted 

 between this district and others ; and an interesting slide from 

 Alderney is described, showing the probable extension of such rocks 

 in other directions. 



' XLIII. Intelligence and Miscellaneous Articles. 



VALLAUKI PKIZE. 



r PHE Academie Jioyale des Sciences de Turin, in accordance with 

 -*■- the will of its associate, Senator Thomas Vallauri, will award a 

 piizeto the savant, Italian or foreign, who between the 1st January, 

 1899, and the 31st December, 1902, shall have published the most 

 important and ihe most eminent work in the domain of physical 

 science, taken in its largest acceptation. 



Another prize will be awarded, without distinction of nationality, 

 to the savant who between the 1st January, 1903, and the 31st 

 December, 1906, shall have published the best critical work on 

 the Latin literature. 



The amount of each of these prizes is 30,000 livres Italian, net, 

 with the exception of a deduction for Italian income-tax. 



The prizes will be paid a year after falling due. They cannot 

 be awarded to Italian members, resident or non-resident, of the 

 Academy. 



No notice will be taken of manuscript works. 



