The invention of barb wire was the most important event in the solution of the fence problem. The question of providing fencing material had become serious, even in the timbered portions of the country, while the great prairie region was almost wholly without resource, save the slow and expensive process of hedging. At this juncture came barb wire, which was at once seen to make a cheap, effective, and durable fence, rapidly built and easily moved. The original patent for barb wire was taken out in 1868, but it was not until six years later that an attempt was made to introduce it into general use, and more than ten years elapsed before the industry attained any considerable magnitude. The rapidity and extent of its subsequent growth will be seen by the following table, showing the estimated amount of barb wire manufactured and in use during the years named, the estimated length being in miles of single strand:

There are now fifty establishments engaged in the manufacture, and the output for 1887 is estimated at 140,000 tons.

Barb wire is not without its drawbacks as a fencing material, the most common one being the liability of serious injury to valuable domestic animals coming in contact with the sharp barbs. Many means have been devised for overcoming this evil. Some of them are illustrated in the next chapter. The direct advantages of barb wire are: First—economy, not only in the comparative cheapness of its first cost, but also in the small amount of land covered by it. Second—effectiveness as a barrier against all kinds of stock, and a protection against dogs and wild beasts. Third—rapidity of construction and ease of moving. Fourth—freedom from harboring weeds, and creating snow drifts. Fifth—durability.

Barb wire, like the harvester, the sowing machine, and most other valuable inventions, has attained its present form from very crude beginnings. The original barb wire consisted of double-pointed metallic discs, strung loosely upon plain wire. The next step was to twist this with another wire, as shown in figure 58.

Another crude beginning was the “horse-nail barb,” which consisted of a common horseshoe nail bent around a plain wire, and the whole wrapped spirally with a smaller wire, as shown in figure 59. Various forms of two-pointed and four-pointed barb wire are manufactured, the principal difference being the shape of the barbs and the manner of coiling them around one or both of the strands. A few of the leading styles are illustrated herewith. Figures 60 and 61 show two varieties of two-pointed barb wire.

Of the numerous styles of four-pointed wire, three typical forms are illustrated in figures 62, 63, and 64.

The Glidden patent steel barb wire is made in three styles, as shown in figures 65, 66, and 67. Figure 65 shows the two-point wire, in which, like the others, the barb is twisted around only one of the wires. Figure 66 shows the “thick-set” which has barbs like the other, but set closer together for such purposes as sheep folds, gardens, or other places, which require extra protection. The four-point barb wire, figure 67, has barbs of the same form as the two other styles, that is a sharply pricking barb attached to one of the wires of the fence strand, upon which the other wire is twisted, holding the barb firmly in place. The barb is at right angles to the wire, and does not form a hook, but a straight short steel thorn. A sharp point which inflict an instantaneous prick repels an animal more safely than a longer and duller barb.

Barb wire of nearly, if not quite all the popular kinds, is shipped from the factory on strong spools, each holding one hundred pounds in weight, or eighty rods in length. These spools are bored through the center to admit a stick or bar, which can be used as an axle in unreeling the wire. The following table shows the weight of wire required for fencing the respective areas named:

It will be observed that the larger the area enclosed, the smaller is the amount of fence required per acre. The cost of fence complete can be estimated by adding to the amount of wire indicated in the last column, the cost of sixty posts, and three and three-quarter pounds of staples, for every sixty rods. To ascertain the weight of wire required for any desired number of strands, multiply the figures of the first column of “weight of wire” by the number of strands proposed to be used.

There is a kind of barb fencing in which flat steel straps are employed instead of wire. In the form shown in figure 68, the barbs are bent around a plain strap and the whole is then galvanized, which firmly fixes the barb. Another form shown at figure 69 consists of a solid piece of steel, ribbed through the middle, and with barbs cut on both edges. These and similar forms are more expensive than wire, and are employed only in limited quantities for enclosing lawns, paddocks, etc. Still another form is like that shown in figure 70, without barbs, and twisted. This is much used to enclose lawns and ornamental grounds. It is light, neat and strong, does not harbor weeds or make snow drifts, but is comparatively expensive, as five or six strands are required to make an effective fence.

Still another form of unarmed fencing is shown in figure 71. It is simply the ordinary wire without barbs, and is used in limited quantities for fencing ornamental grounds, barnyards, etc.