History of the big bonanza

by Dan De Quille

When the true dip of the vein had been ascertained, it was then seen that its apparent dip to the west was owing to the pressure of the superincumbent rock and earth, on the steep side of the mountain, having pressed down the upper part and bent it over to the east. When those who had located claims on the side of Mount Davidson, and adjacent mountains, saw the Comstock lead thus turning tail and leaving them, they stood aghast. Those who had located to the eastward and had mourned because they could do no better, were now happy men—the Comstock was making toward them.

In December, 1860, the Ophir folks had attained a depth of but 180 feet in their mine. They were working down in the heart of the bonanza, or rich ore-body, and at that depth the breadth of ore was forty-five feet. No such great width of ore had ever before been seen, and the miners were at their wits’ end to know how to work it and keep up the superincumbent ground—how to support such a great width of ground with timbers, was the question. The ordinary plan of using posts and caps would not do, as posts of sufficient length could not be obtained, and, even though they could be had, would be inadequate to the support of the great weight and pressure that would be brought to bear upon them. In this emergency the company sent to California for Mr. Philip Deidesheimer, a gentleman who had had much practical experience both in the mines of Germany and those of the Pacific coast.

After Mr. Deidesheimer arrived and was placed in charge of the mine as superintendent, he worked upon the problem before him for three weeks before he arrived at a satisfactory solution. He then hit upon the plan of timbering in “square sets” which is still in use in all the mines on the Comstock, and without which they could not be worked. The plan was to frame timbers and put them together in the shape of cribs, four by five or six feet in size, piling these cribs one upon another—but all neatly framed together—to any desired height. Thus was the ground supported and braced up in all directions. Where the vein was of great width, a certain number of these cribs could be filled in with waste rock, forming pillars of stone reaching up to the wall of rock to be supported—up to the roof of the mine.

Previous to the invention by Mr. Deidesheimer of the system of timbering by means of “square sets,” the only supports used in the mines were round logs cut on the surrounding hills. These logs were from sixteen to thirty-five feet in length. When of the latter length they were manufactured, that is, were made of two logs spliced and held together by means of iron bolts and bands. Owing to the stunted character of the pines and cedars found in the neighborhood it was almost impossible to procure a log more than twenty feet in length. After setting up two of these long logs, a log about eighteen feet long was placed upon them as a cap. These posts and caps were placed as close together as they could be made to stand, but then would not hold up the ground when it began to slack and swell from exposure to the air.

Besides this difficulty there was no safe way of working either above or below these sets, in the vein. To take out ore, either under or over the timbers, loosened them and caused a disastrous cave. Many accidents happened and many men lost their lives while this method of timbering was practiced, but no lives have ever been lost in timbering by the square-set or Deidesheimer plan. In the mines at Gold Hill was where the timbers thirty-five feet in length were used, and there was where the greatest number of accidents happened; but in the Ophir mine, timbers sixteen feet long had been used.

When the miners of Gold Hill heard of the new mode of timbering practiced in the Ophir mine, they went up to Virginia to see it, and found it was just what was required. Mr. Deidesheimer sent some of his carpenters down to Gold Hill to show the workmen there how to frame the new timbers, and how to set them up. In 1861 this style of timbering was adopted along the whole line of the Comstock and has been in use ever since. The Ophir was probably the first mine in any part of the world where such a system of timbering became a necessity, as no ore-body of such great width had ever before been found. Nothing seen in the Comstock mines more surprises and pleases the mining men of Europe than this mode of timbering. It is a thing none of them has ever before seen or thought of, and its utility is so strikingly obvious that they can hardly find words in which to adequately express their great admiration of it.

In 1861, Mr. Deidesheimer prevailed upon the Ophir Company to put up a forty-five horse-power engine, an eight-inch pump and improved hoisting machinery for the incline of the mine. The company thought this a fearfully extravagant move, and were almost frightened out of their wits when this “tremendous” machinery was first mentioned. Now there is hardly anything in the shape of a mine anywhere along the Comstock range on which there is not in operation more powerful and costly machinery.

At the depth of 180 feet, at what was called the third gallery, the width of the ore was, as I have said, 45 feet; at the fourth gallery it became 66 feet in width, and the miners were delighted to find that the new timbers supported the ground in the most perfect manner. At this time the ore extracted from this first bonanza was assorted as it was extracted. That which would average $1,000 per ton was sacked up and shipped to England for reduction, while the remainder was piled up as second and third-class ore, to await the erection of proper mills for working it at home. At the Mexican and other mines in the neighborhood, about the same disposition was at this time being made of the ores taken out, while at Gold Hill they had not yet attained a sufficient depth to reach the silver, and were working their ores for gold alone; though much silver was obtained with the gold.

TIMBERING OF A MINE.