Numerous specimens of fresh sulfide ore were collected at various mines throughout the district in 1923. Detailed laboratory examination of these was made, and these investigations definitely prove the primary character of the unaltered auriferous pyrite and galena. The gold and silver associated with these may reasonably be expected to persist with depth; to what extent they persist must obviously be proved by development. In this connection it is well to call attention to the fact that some low-grade sulfide deposits will not pay in themselves except throughout the upper oxidized zones where enrichment has occurred; or, in other words, rich oxidized deposits will not necessarily lead down to rich sulfides. However, the deposits in certain areas still on the border land between the zones of oxidization and of sulfide minerals warrant prospecting for primary ore.

ORIGIN OF THE DIKE DEPOSITS

An important phase of the ore deposition was evidently overlooked or disregarded by the pioneer miners. An understanding of the relation which secondary enrichment bears to a particular property is necessary for a successful solution of mining and metallurgical problems involved. Through this phase of deposition was not in evidence at all places, it was decidedly so at most of them.

Throughout the country rock of the oxidized zone, in the vicinity of ore-bearing quartz veins, is sometimes found a wide dissemination constituting a low-grade gold ore, assaying from a few hundredths to several tenths of an ounce to the ton. Such mineralized zones generally extend from 150 to 200 feet in depth, and often 100 feet or more laterally on one or both sides of the vein, depending upon the permeability of the enclosing rock. The descending acid solutions greatly alter invaded rock. It is generally so decomposed that very little powder is needed to break it; in fact, much of it is what the miners call picking ground. Stains and deposits of iron and manganese are everywhere evident in fissures and on cleavage planes of the rock around the margins of the old stopes. The dark dendritic manganese stains stand out prominently on some of the lightercolored rocks. Throughout such oxidized zones, low-grade gold values are everywhere associated with the manganese occurrence--not necessarily mixed with it, but in the same vicinity.

Past work has clearly shown that the disseminated deposits cease rather abruptly at the bottom limit of oxidation and that, thereafter, the values are confined to, or closely associated with, the quartz and sulfides of the fissure veins. Of such a nature are most of the so-called dike deposits of the district. The Butte and Orogrande, or Hogan mine, at Orogrande, is the best developed ore body of this type, and from it 100,000 tons of ore said to average $3 per ton have been milled.

ZONES OF NARROW QUARTZ VEINS

In some of these mineralized areas no large quartz vein is evident; instead, there will be found a comparatively narrow zone of small quartz veins and branching stringers cutting through the country rock. These veinlets often carry considerable gold, but the low-grade ore, referred to above, is to be found in the altered country rock away and apart from the quartz veins. The absence of such dissemination in the sulfide zone is the deciding factor.

One place visited showed another phase of the enrichment process wherein the enrichment was confined almost entirely to a 4-foot vein and did not appreciably affect the enclosing country rock. Here, the oreshoot is highly stained with manganese oxides and extends upward to within a few feet of the surface and for 160 feet along the drift. The ore averaged close to $85 per ton and plated between $55 and $60. The rich ore was bottomed at 15 feet below the creek level. A 110-foot shaft, sunk to explore the vein at depth, disclosed values in the sulfide zone ranging between $6 and $10 per ton.

FUTURE PROSPECTS OF THE AREA

The lack of suitable highways is such that, under existing transportation conditions, only placer mining and the working of bonanza gold veins could be expected to show a profit. The outstanding question regarding the area is therefore, Can lode mining be conducted at a profit when motor truck highways become available? The answer to this significant and indeed crucial question depends upon three major factors: (1) The size and persistence of the veins; (2)

the gold content of the veins and its longitudinal distribution therein; and (3) the depth to which a workable gold content may be expected to continue. Each of these will be discussed in order.

(1) The size and persistence of the veins

In the various districts which have been mentioned the following observations have been made on this point:

Such veins compare favorably, so far as size is concerned, with the gold veins of Australia, California, and Cripple Creek. The so-called dike deposits are purposely omitted from the tabulation given above.

It is axiomatic that a certain relationship exists between length along the strike of a vein and its persistence on the dip, and such being the case it is apparent that the gold veins of central Idaho cannot be classed as gash veins lacking depth.

(2) The gold content of the veins and its longitudinal distribution therein

It was clearly beyond the scope of the present investigation to attempt any systematic sampling of the numerous veins examined, even were such a course possible in the face of the well-known difficulty of sampling ore bodies containing free gold. Mill returns afford perhaps the best criteria, and the following figures are presented as bearing on this point:

The question of the longitudinal distribution of the gold content is still an open one. Surface enrichment has been so important a factor in, and for a slight distance below, the oxidized zone, as to obscure the localization of the gold content in primary ore shoots, except in those few properties where development has been sufficiently extensive to get below the permanent water level. Nevertheless, the Jumbo and the Big Buffalo mines afford indubitable evidence of such localizations; so also do the War Eagle and the American Eagle mines. That such shoots may be connected with cross fissuring appears probable. Some of the former operators in Buffalo Hump, where the greatest development has been done, thought that the shoots were too far apart to make profitable working possible, but it appears to me that any definite conclusion on this point is beyond the limits of present knowledge. A negative answer is not warranted. (3) The depth to which a workable gold content may be expected to continue The dread specter of superficial richness has certainly done as much as lack of transportation to delay the development of the gold field of north-central Idaho. Indeed, it has doubtless contributed to the apathy which has so long

delayed the needed transportation. It is to be admitted that the cost would be considerable, so that inaction in this respect is quite understandable. The issuance of the report mentioned has been delayed, so that there might be ventured at least a qualified laying of the ghost, and the conclusion is reached that although surficial enrichment has played an important part in the region and must be kept well in mind in all future developments, there are nevertheless excellent reasons for believing that primary ore of workable grade persists in at least certain parts of the area to depths far below that attained by present workings.

I have been especially impressed by the small amount of development work in proportion to the surface evidences of persistent mineralization, and I feel no hesitation in saying that in many of the districts herein described, much greater boldness in development than has yet been shown is abundantly justified in light of the essential facts.

NATIONAL FOREST WILDERNESS AREAS

UNITED STATES DEPARTMENT OF AGRICULTURE,

Hon. COMPTON I. WHITE,

House of Representatives.

FOREST SERVICE, Washington 25, April 7, 1950.

DEAR MR. WHITE: Reference is made to your letter of April 5 in which you request advice as to the extent and acreage of the primitive areas in central Idaho.

Enclosed for your general information is a publication National Forest Wilderness Areas, which lists all of the wilderness, wild, roadless, and primitive areas and explains the purposes for which these areas are maintained. There is also a map showing the distribution of these areas.

On pages 7 and 8 you will find that Idaho has three such areas the Idaho, 1,232,744 acres; the Sawtooth, 200,942 acres; and the Selway-Bitterroot, 1,581,210 acres. A small part of the Selway-Bitterroot area is in Montana.

Except for the three roadless areas in Minnesota we now call all of these wilderness or wild areas, which are the names approved by the Secretary's regulations U-1 and U-2, but many of the areas were classified under the former regulation L-20, which called them primitive areas. Actually there is no real difference and the areas are now managed according to the policies set forth in regulations U-1 and U-2, copies of which are enclosed for your information. Please let us know if you have any further questions. Very sincerely yours,

LYLE F. WATTS, Chief. By C. M. GRANGER,

NATIONAL FOREST WILDERNESS AREAS

The national forests contain many of the last remaining parts of the country that are still in much the same primitive state as when the first settlers reached their vicinity. They include many of the mountain ranges and peaks that the pioneers saw not only as landmarks but also as spiritual symbols of a new world and a new life. Most of the Nation's wild areas have been conquered by highways, by motor transportation, and by the invasion of increasing numbers of people who bring with them the social and mechanical devices developed by civilization. As modern developments continue, the interests of recreation, public education, and science have made it increasingly desirable to preserve representative areas of our original wilderness.

To contribute toward the satisfaction of this need, the United States Forest Service has designated 77 areas within the national forests to be preserved as wilderness. They embrace a total of 14,000,000 acres on 73 national forests in 11 States; 28 of the 77 established areas exceed one hundred thousand acres in extent and are known as wilderness areas. Forty-six of smaller size but of 5,000 or more acres each are called wild areas. Three, on which restriction of commercial use is less rigid, are designated as roadless areas.

Uses of these areas are limited to those consistent with wilderness values. Most of these areas are still classified under regulation L-20 as primitive areas; others under the later wilderness and wild area regulations (U-1 and U-2) established by the Secretary of Agriculture in 1939. For convenience all areas whether actually classified as primitive or wilderness are now referred to as wilderness or wild areas, since, except for a few cases, their management is identical. Administratively the Forest Service will handle all primitive areas as if they were classified as wilderness or wild areas.

The total area thus reserved is approximately 8 percent of the land area of the national forests. At first glance this might appear to make a significant inroad on the Nation's timber supply. However, while the areas are generally the best available to represent primitive conditions in various regions, they are usually the least productive of commercially valuable timber. Considerable portions of these areas are above the timber line or have only noncommercial timber growth.

Most of the timber stands on the remaining portions are inaccessible because of location. The public is thus assured of preservation of the wilderness without material sacrifice of usable timber. In selecting these areas the Forest Service very carefully weighed the value of the area for wilderness as against its value for other public uses important to the economic welfare of the region. Although many of these areas have outstanding scenic values, that was not why they were established. They were selected as typical areas of the Rockies, Sierras, Cascades, and other regions where wilderness lovers and recreationists may enjoy unmodified nature and the inspiration it gives.

Areas of similar character exist in many national forests of the East but not of sufficient size to be formally classified as wild or wilderness areas. A number of these smaller remnants of primitive forests are in the Appalachians, Alleghenies, and in the Presidential Range of the White Mountains. These small primitive tracts are available for use and for some purposes 1,000 acres may be as much a wilderness as 100,000 acres.

Wilderness areas are designated by the Secretary of Agriculture upon recommendation of the Chief of the Forest Service. To come under this category, there must be no roads or other provision for motorized transportation, no commercial timber cutting, and no occupancy under special-use permit for hotels, stores, resorts, summer homes, organization camps, or hunting and fishing lodges on such lands.

Grazing of domestic livestock and improvements necessary for fire protection may be permitted on wilderness areas, subject to restrictions made by the Chief of the Forest Service. Within designated wilderness, the landing of airplanes on national forest land or water and the use of motorboats on national forest waters are prohibited, except where such use has already become well established or is required for administrative needs and emergencies.

Regulations further provide that "wilderness areas will not be modified or eliminated except by order of the Secretary of Agriculture. Notice of every proposed establishment, modification, or elimination will be published or publicly posted by the Forest Service for a period of at least 90 days prior to the approval of the contemplated order, and if there is any demand for a public hearing, the regional forester shall hold such hearing and make full report thereon to the Chief of the Forest Service, who will submit it with his recommendation to the Secretary." It is the policy of the Department of Agriculture to allow modifications of established wilderness areas only when it is clearly in the public interest to sacrifice wilderness values in favor of other public needs.

Similar regulations apply to the establishment and maintenance of the smaller wild areas, except that decision is by the Chief of the Forest Service instead of the Secretary of Agriculture.

In addition to the 14,000,000 acres of specially designated wilderness areas, there are many small tracts in the national forests which are at least partially wilderness in character and would be thought of as wilderness by most people. The Forest Service takes into consideration human needs in administering the national forests, and to this end, woodlands and regulated wild lands are, first and foremost, managed so that they will permanently contribute as much as possible to the welfare of the people, to the stability of homes and communities, and to the solution of various national problems. Thus, lands within the national forests are devoted to timber production, production of range forage for livestock, mining, watershed protection and waterpower development, game and wildlife production, recreation, and various other uses or combination of uses, under careful plans of management which seek to coordinate all such uses and bring about "the greatest good for the greatest number of people in the long run." Within this pattern, which foresters call "multiple-use management,” preservation of representative areas of wilderness has a place and serves a public need.

Other parts of the national forests provide developed recreation facilities which include motor roads, improved camping and picnic grounds, boating, beaches, resorts, winter sports developments, and other vacation aids. They offer opportunities for those who want to have their forest outings in motorcars, and for those who want to get away from motorcars. The wilderness areas provide for real wilderness outings, far from any of the attributes of modern civilization. Access to some of the wilderness areas is comparatively difficult. Wilderness areas are open to the public without restrictions except those essential for protection from fire. Hunting and fishing are permitted in wilderness areas in accordance with State laws.