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and to spare for all who are present, and for all that may hereafter arrive, for at 

 least the next half century. There need be but little fear of their failing to yield 

 their annual crop of gold, as long, perhaps, as our valleys will yield their crops of 

 grain. 



The aggregate areas amount to about eleven thousand square miles, that is 

 known to contain gold ; and, when this is compared with the area actually occu 

 pied, the latter will be found to comprise but a mere mite of our available 

 resources. With our present population of the mining districts, and the broad 

 expanse of territory over which they are spread, they appear like mere specks, 

 dotting the surface of an inland sea, so indistinct as scarcely to be appreciable on 

 the broad expanse by which they are surrounded. 



QUARTZ VEINS. 



In my report of last year, it will be seen that the quartz veins of the State 

 were divided into separate groups denominated the older and recent groups, 

 each having a different age and apparently belonging to different geological per 

 iods. These were again separated into three divisions, each occupying certain 

 districts of the State, and the divisions of the older group were found run 

 ning in lines nearly parallel with each other. 



It will be necessary briefly to allude to the relative disposition of these veins 

 among their investing rocks in order to obtain a better idea of the positions and 

 relations of other veins which have been developed with the year that has pass 

 ed. 



That group which was denominated the " older," and which includes the east 

 ern and more central line of dikes that traverse the inland districts of the State 

 pursue a strike which is nearly north and south. This intrusion occurred evi 

 dently during the period immediately preceding the upheaval of the rocks be 

 longing to the tertiary epoch, the proofs of which are found in the part that in 

 no instance are they known to have disturbed the rocks of that date, though 

 often found closely adjoining the latter, and which in some instances are found 

 to overlie the dikes themselves. 



The uniformity which these rocks present in their latitudes with the rocks by 

 which they are invested, compels us to admit that they must be regarded as a 

 distinct group, equally as marked in feature as are any of the different beds 

 which go to make up any series found in the sedimentary rocks of any portion of 

 the State. 



To the west of this suite of veins, are found the more recent dikes, and which 

 were called the " recent group." These extend from the edge of the plain 

 eastward for about fifteen miles, and in some few instances have been found in 

 truded among the rocks of the preceding period. 



The peculiarities that remove these veins from the former, is found in the fact 

 that they have disturbed not only the primitive but also the most recent of the 

 tertiary rocks of these districts, and as late as the pliocene group in other parts 

 of the State, abundant evidences of which are met with in many parts of the 

 coast mountains. 



The course of the recent dikes diverges from those of the older at an angle 

 of about twenty-four degrees, their mean trend being south twenty-four degrees 

 east, and north twenty-four degrees west. Were these peculiarities merely local, 

 we might with some degree of reason assign to the entire series a cotemporane- 

 ous age, the characteristics noticed pervade so great an extent of country that 



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