NOTES AND QUERIES. 



2G9 



the earliest antiquity, Laving exercised an important influence on the 

 history and social economy of the ancient Etruscan people ; and evidence 

 of ancient workings, assignable to Etruscan, Homan, and mediaeval ages, 

 have been often encountered in modern explorations. In the late Inter- 

 national Exhibition, M. Hauft, of Florence, exhibited a series of plans and 

 synoptical tables illustrating this subject. Amongst these were special 

 plans, on a scale of three inches to a mile, showing that the mineral veins, 

 fumerolas, brine-springs, and lines of volcanic activity, have a remarkable 

 amount of parallelism, and form two great groups, the intersections of 

 which are the chief seats of mining enterprise. This double parallelism 

 has also been observed to exist in the mining region between the Apuan 

 Alps and Mount Amiata. The average direction of the first group is 

 3° W. ; the extremes lying between N. 28° W., and N. 11° E., or a total 

 variation of 39°. The mean direction of the second group is N. 54° W. ; 

 the- extremes N. 67° W., and 1ST. 45° W., or 22° of variation. The direc- 

 tion of the brine-springs is JS". 46° W., the variation being 7° on either side. 

 The course of the deposits of alum worked at Montione and Erassine is 

 similar to the salt group, viz. W. 50° E. ; the fumaroles, whose vapours 

 contain boracic acid, are arranged in four series, having a mean direction 

 of N. 47° W., with a variation on either side of 5|°. Two other lines of 

 fumaroles have a direction N. 12° E., which coincides with the strike of 

 the four great deposits of iron ores existing in the island of Elba. The 

 lines of strike passing the marble quarries near Seravezza, give directions 

 N., and INT. 53° W. The direction of a line passing the mines of Montieri, 

 Gerfalco, and Poggio Matti, JN\ 48° W., or parallel to the line of the sub- 

 terranean fires of Mount Oggioli, Pietramala, and Peglio. The directions of 

 the three gigantic metalliferous lines of the district of Massa are N. 13° W., 

 N. 11° W., and N. 3° W., while that of the deposit of alum at Accessa, Monte- 

 rotondo, and Sasso is ~N. 7° W. All the above lines of bearing are in- 

 cluded between the directions JNT. 28° W., and ~N. 12° E. in the one case ; 

 and between N. 67° TV., and N. 46° W. in the other, — an amount of varia- 

 tion so small, that M. Hauft has concluded that in Tuscany the various 

 metalliferous deposits, as well as those of alum and sulphur, the brine- 

 springs, and the various volcanic emanations, are all different phases of one 

 great formation, due to causes still in active operation in the production of 

 borax, petroleum, sulphur, etc. This formation is, he says, divisible into 

 two periods of unequal value, as far as minerals are concerned, for many 

 of the veins contain no metalliferous substances, and it is only in a few of 

 the metalliferous deposits of the Maremmana formation that silver ores 

 occur. The above conclusion is verified, he considers, by other coincident 

 circumstances. The two lines which unite the extreme points in the salt 

 districts, and include the four principal series of boracic acid, soffioni, are 

 parallel to one of the leading lines of mineral veins ; the line passing through 

 the fumaroles of Lucignano and Serrazzano, combines exactly with that 

 uniting the saline springs of Eontebagni, Loriano, and Scornellina ; while, 

 in like manner, the line joining the fumaroles of Monterotondo and Sasso 

 coincides with the line of salt-springs rising between Eattagliana and 

 Prugnano. This relation between the most important borax districts and 

 the metalliferous country of Tuscany has led to the supposition that they 

 may be regarded as in some sort a continuation of the latter. In addition 

 to these cases may be added the occurrence of borax and alum at Sasso 

 and Monterotondo, and the association of alum deposits with mineral 

 ores at Accessa, both of which are in direction JST. 12° W. In the same 

 manner, the fumaroles of the lake of Monterotondo correspond, on the line 

 of N. 49° W. with the mines of Cugnano, and in the direction W. 3° E. 



