FOURTH REPORT OF THE DIRECTOR iQO/ 33 



the evidence is insufficient at present to place the magnetites defi- 

 nitely with either. The igneous rocks which carry the ore belong 

 to several types, ranging from acid granites on the one hand to 

 granites poor in quartz, syenites and even more basic phases that 

 approach the gabbro-anorthosite group which contains the titanifer- 

 ous ores. It appears very probable that there is a close relation in 

 the geological occurrence of both classes of ores found in the igneous 

 rocks, since the latter show the most intimate connection in their 

 fundamental characters. Like the titaniferous class, the low- 

 titanium ores (they are not strictly nontitaniferous) are native to 

 the wall rocks and have formed in their present place by some 

 process incident to the cooling and consolidation of the latter. 

 Magmatic segregation has perhaps been influential in some instances, 

 as has already been pointed out by Gushing, but the mineral asso- 

 ciations of most of the magnetites point to gaseous or gas-aqueous 

 agencies as the more important factor in the process of formation. 

 The ore bodies originated previous to the dynamic stresses which 

 have affected the whole region and thus have been drawn out and 

 alined parallel to the general foliation. The magnetites found in 

 the sedimentary gneisses differ from the others in several respects. 

 They are always pyritic and have, as associated minerals, garnet, 

 scapolite, sillimanite and usually much hornblende. Their origin 

 is doubtful as the evidence bearing upon it is subject to different 

 interpretations. They may be ancient beds interstratified with the 

 wall rocks or later introductions due to ground waters or insula- 

 tions set up by the igneous invasions. They are frequently cut by 

 granitic masses and they are possibly an older series than the other 

 magnetites. 



The mining industry of the Adirondacks has grown considerably 

 in the last two or three years. The outlook for its future seems 

 quite promising. Not only are the low-titanium ores being de- 

 veloped on a larger scale than previously, but there is a good pros- 

 pect that the titaniferous deposits will soon be worked on a com- 

 mercial scale. The new enterprise at Lake Sanford, mentioned in 

 the issue of this report for 1906, has been active during the current 

 year in carrying on investigations ; productive operations only await 

 the construction of a railroad to the locality which is in a now inac- 

 cessible part of the Adirondacks. 



In accordance with the recommendation made in my repo't of 

 last year the Legislature granted a specific appropriation for the 

 exploitation of the Clinton hematite ores of central New York. . It 

 was therein pointed out that a large body of these ores lies almost 



