In most cases the foundation was constructed of separate bents such as shown in Figure 6, consisting of a heavy mudsill on which posts were erected to take the heavy cross timber on top. The foundation would be built up of two to five such bents spaced apart from front to back of the pile length, each bent to the rear being progressively shorter to give the desired slant backward. If three bents were used, the middle bent would be placed midway of the end

FIGURE 5.-These pile bottoms are too close to the ground, and further
handicapped by the growth of weeds. Photograph courtesy of
Forest Products Laboratory

bents or a little farther toward the front. Where four are used on a 16-foot length of foundation they are often spaced 6-4-6 feet, or sometimes with the 4-foot spacing at the front, because the forward pitch of the face of the pile throws most weight on the front of the foundation, and if the second bent is placed closer it takes a portion of the weight off the front bent.

6*6

MUDSILL 3X12X16

FIGURE 6. Sketch of a typical bent for cross-foundation, the top forming the crosser, so as many bents are used as crossers are desired. By making such a bent lower at one end for desired pitch of the pile they can be combined into a longitudinal foundation, two bents at the sides and one in the middle, to take movable crossers. Such bents when set for a foundation are heavily cross-braced

The bents forming a foundation, after being set up and properly spaced, are strongly cross braced to each other, 2 by 6 being the size of brace most commonly used and the bracing usually being applied at both sides of the foundation and in the middle.

As each bent forms a crosser under the lumber, the number of bents depends upon the number of crossers desired. The use of three crossers for shorter lengths of lumber, and four for longer, was the

most popular combination reported by the mills and is used by 38.6 per cent of the reporting mills. These mills, however, did not make the boundary line at the same length division. Just half as many mills, or 19.3 per cent, use three crossers for all lengths of lumber, of course spacing them to suit the length. A combination of 2 to 3 crossers was used by 12.3 per cent of the mills, while 7 per cent used 2 crossers as a minimum and 4 or 7 crossers for longer lengths of lumber; 10.5 per cent used 4 crossers either for all lengths or as a minimum length, with 5 or 6 crossers for greater length ranges; 3.5 per cent use 3 crossers as a minimum and up to 5 or 6 crossers for longer lumber. The balance, or 3.5 per cent, use a minimum of either 5, 6, or 9 crossers, ranging up to a maximum of 5, 6, 7, 8, or 16 for longer lumber. One southern pine manufacturer uses 2 to 7 crossers, but with this exception the use of more than 4 is not found in any of the reports for northern hardwoods, northern pine, cypress, southern pine, Douglas fir, or western pine. The combinations of 4 to 7, 6 to 8 or 9 to 16 crossers were reported only in southern hardwoods.

In most cases the foundations were built in variations of 2 feet total length to suit the exact lengths of lumber to be piled. At some mills the practice is followed of building foundations 10, 14, and 16 feet long and letting these same foundations answer also for lumber 12, 16, and 18 feet in length, with 2 feet overhang. Sometimes in such a case the rear line of stickers is carried outward at an angle until it reaches the ends of the lumber, and the stickers are carried flush with the ends the rest of the way, or perhaps with a slight projection.

In about one-third of the reports indicating the general type of construction shown in Figure 4 the posts and mudsills were replaced by concrete piers.

In the 22.7 per cent of foundations where the heavy timbers run lengthwise of the pile the foundation may be built up of individual bents as in Figure 4, but the bents are built lower at one end than the other, according to the pitch desired in the pile. For narrow piles two of these bents are set in the side lines of the pile; for wider piles a third bent is placed midway of the length of the pile. Crossers are laid across these stringers to take the lumber, and these are usually loose and may be varied in size or number to suit whatever length of lumber or spacing between crossers may be required. Such a foundation can therefore take longer or shorter lumber within the length limit to which the stringers are adapted. Such foundations were reported in two-thirds of the reports for southern hardwoods, in half the reports for northern hemlock and hardwood, and for southern cypress. In the latter wood one manufacturer reported the use of a double longitudinal foundation to take two piles side by side with 4 feet of space between them. The piles were 6 feet wide, and the foundation consisted, therefore, of four stringers spaced 6, 4, and 6 feet on posts supported on mudsills; and the foundations were tied together by two 16-foot cross timbers, one at the front and the other two-thirds of the way back, and suitable bracing. The lumber was carried on movable 6-foot crossers laid on the stringers.

For general use the chief advantage of the longitudinal foundation, as shown in Figure 7, is that it may be changed to take another length of lumber by rearranging the loose crossers on top of the stringers. In sawmill piling this is not of so great advantage, as the yard is usually laid out so that each foundation is used permanently for a single length of lumber. Here the chief advantage of the longitudinal type is that only three bents are required for kinds of lumber on which it is desired to use more than three crossers, while with the crosser type of foundation there would be as many bents called for as

FIGURE 7.-Showing how stringer foundations are adaptable for either
full-length or shorter piles of lumber. Photograph courtesy of Forest
Products Laboratory

the number of crossers required, unless two lines of stickers are started on a single foundation crosser and separated gradually to get the required spacing.

In more than half the reports received the type of foundation bent shown in Figure 6 is varied by substituting a pile of blocking for the vertical posts (fig. 8), and the through mudsill shown is replaced by mudsill blocks for each foundation support. The size of foundation timbers varies materially; mudsills are 2 by 12, 3 by 12, 6 by 10, 6 by 12, and 3 by 24. For these some special decay-resisting wood is often selected; redwood or western red cedar (in one case incense cedar) in the far West; tamarack or northern white cedar in the

A

North; and cypress or oak in the South. Posts range in size from 6 by 6 to 12 by 12, and crossers from 3 by 6 to 12 by 12.

The recommendation is often seen that treated material be used for pile foundations. The questionnaire contained a specific inquiry on that point, but the replies showed only one instance where preservatives are used. At this mill the foundation cross timbers are set on concrete piers, and the timbers and bracing are brush-treated with creosote. This report was from a large southern pine manufacturer.

It is often recommended that a fresh strip be laid on top of an old foundation crosser before piling the first layer of lumber. A specific inquiry as to the use of this method brought replies showing that it is used at about one-third of the yards and for all species, except that it was not reported for either red wood or western pine. In some cases this strip, instead of being renewed at each new piling, is used as long as it remains bright and sometimes is nailed along the

FIGURE 8.-Foundations supported on heavy wooden blocks instead of posts or piers. Photograph courtesy of Forest Products Laboratory

middle of the heavy crosser, in which case its chief purpose seems to be to afford a narrower surface contact with the board and thus have less retardant effect on its seasoning.

Before leaving the subject of lumber foundations two special arrangements reported will be mentioned. At a northern hemlock yard there are two endwise foundations on each side of the elevated tram on which short hemlock is piled, and a double roof is provided to cover both piles, as shown in Figure 9. At the redwood yard of the Red River Lumber Co., Westwood, Calif. (fig. 10), all piling is done by locomotive crane, and there are two depths of piles on each side of the main-alley railroad track, with 4 feet of space between them and a liberal back space to the two piles on the next alley. Another rather eccentric method of double-length piling of short hemlock is shown in Figure 11, where two lengths are piled end to end in the same pile and are lapped where they join, without stickers. Drying would be better at this point if the lapping were made considerably shorter than shown.

In some mill yards where there is a wide main alley narrow foundations are provided along the middle of the alley for the storage of stickers and roof boards when not in use; and sometimes small foundations are provided in the rear on which rejects can be piled and

FIGURE 10.-Locomotive crane loading out lumber in yard of Red River Lumber Co., Westwood, Calif. The piles are all built up with unit packages placed by crane, and as shown here are two ranks deep either side of the crane track, with 4 feet of end space between piles. Photograph courtesy of Red River Lumber Co.

kept clean and off the ground until they are distributed. Such lumber must often be sent through the planing mill for refinement and salvage, and dirt on the lumber works havoc with planer knives. Storing stickers between lumber piles is a poor expedient, as it interferes with air circulation through and below the pile bottoms. Fig