Before driving, the piece is capped with an iron hoop to prevent splitting and the lower end is protected with an iron shoe.

Although other species have been tried for dock work, southern pine, in spite of its price, has been found without an equal, the cost of the timber being of secondary importance compared with the importance of the work involved and the safety of the workmen's lives. În addition to the square piling timber, planks 6 by 12 inches and 7 by 12 inches are also used for heavy joists. Temporary railroads for carrying material are frequently built during the construction of a large dock, which often takes several years to complete, and for these southern pine switch ties or crossings 6 by 12 inches are required. While most sheds are now built of reinforced concrete, considerable quantities of southern pine timber is used for temporary supports and for concrete forms.

In addition to the building of the dock itself, piling of this wood is also used for boat landing and amusement piers and breakwaters. Generally speaking, southern pine and Douglas fir are treated before being used for permanent work, while if for temporary structures they are used untreated.

Douglas fir.-Next to southern pine the wood most used in dock construction is Douglas fir. While the first-named species is still often preferred, the increasing difficulty in obtaining the long lengths and large sizes required for this work, together with advancing values, is causing Douglas fir to be used now where formerly it would not have been considered. While the quantity so far used for this purpose is comparatively small, its use is steadily increasing not only for bulkheading and other temporary work but for permanent work also.

Greenheart.-In order to keep the water from running out with the falling tide, docks are entered from the main waterway through gates which are usually opened for the entrance and exit of vessels during a limited period before and after high water. These gates are of exceedingly massive construction, as is necessary if they are to successfully withstand the pressure when the water level is lower on one side than the other. For the building of dock gates greenheart has been used in Great Britain ever since the present methods of dock construction have been practiced. It stands salt water without decay, resists the ravages of the teredo, and has been found sound after being used for 50 years.

In addition to dock gates, greenheart is used for piling and pierhead decking, but its high cost limits its use for this latter purpose.

Elm. Both native and Canadian rock elm are used to a small extent, principally as fenders on dock gates and aprons, also on landing piers, as a protection from ships rubbing against them.

Other woods used.-Among other woods used are Quebec spruce for scaffolding boards, lower port Canadian spruce and north European softwoods for ordinary dam and sheeting work, while north European matching is used to some extent for shed doors, although most of these are now of metal on account of its fire-resisting qualities.

In addition to these, Quebec white pine is used for pattern making, although the quantity required is comparatively small. Formerly some Australian karri and jarrah was used for dock piling, but it is doubtful if any has been used for this purpose during recent years.

USE OF SUBSTITUTES

There has been a notable increase in the use of concrete during the past few years as a substitute for wood in dock and harbor construction. So far, it has not been found suitable for temporary bulkheading where the piling is drawn and used several times; also its lack of elasticity is a serious defect for, while wood will bend to a certain extent with the varying pressure, concrete will break. Another objection to concrete is that should the pile break when being driven

it is difficult to withdraw the lower part, while, on the other hand, if under exceptional conditions a piece of wood piling breaks, it never does so clear through and no difficulty is experienced in pulling it out of the ground.

For permanent piling and apron work, however, there is a very definite movement toward concrete, a fender of elm being generally attached to protect it from damage by vessels colliding with it.

BOXES, CRATES, AND PACKING CASES

While no statistics are available as to the imports of box shooks or no data available regarding the consumption of lumber for the manufacture of boxes, crates, and packing cases, there is no doubt that very large quantities are needed not only for domestic requirements but also for the export trade, particularly of textile fabrics.

Generally speaking, the industry may be said to be divided into two groups, namely, the plants operated by manufacturers of products packed in standardized cases who make their own containers out of shooks, and plants operated by private companies specializing in the manufacture of wood containers. The principal business of the latter is catering to the needs of those whose requirements are not large enough to justify the operating of a box-making plant, and the great miscellaneous market which orders only a small number of containers of one particular size at a time, but the volume of whose business in the aggregate is considerable.

There is still a third group-i. e., forwarding agents—who, having a special knowledge of the requirements needed for particular goods destined to foreign countries, do the packing for their principals.

SPECIES USED AND SOURCES OF SUPPLY

Pine and spruce from northern Europe and to a lesser extent spruce from central Europe and Canada (the latter being confined largely to the Manchester district) constitute the principal woods used in Great Britain for boxes and packing cases. Where an odorless wood is required for packing food products spruce is always used.

If the lumber is required for the manufacture of standardized containers, it is imported in shook form, but if for the general box and packing-case industry the lower grades and short lengths of rough-sawn lumber and "firewood" are used. In addition, there are also imported round logs or "roundwood" from the White Sea district which are resawn into box lumber.

The softwoods mentioned hold nails well, take a smooth saw finish, and in addition are light in weight, an important factor where expensive transportation charges are involved.

PRODUCTION

Boxes, crates, etc.-According to the Census of Production, 1924, the output of firms making returns for wooden boxes, crates, and cases in Great Britain had a selling value of £5,370,000, the details of which are shown in the following statement:

Crates, cases, and boxes for packing merchandise (including rolling Selling value boards for cloth pieces)

Chests and other wood boxes, etc..

£4, 708, 000

166, 000

Sawmill products

58,000

Firewood..

33, 000 358, 000

received for work done)--

17, 000

5, 340, 000

The aggregates shown in the foregoing do not express the value of all wood boxes, and crates, manufactured, inasmuch as these

goods are produced as a subsidiary line by many woodworking firms whose returns are included in schedules for the lumber and related trades. The values are also exclusive of the output of crates and boxes made by manufacturing and merchanting firms for packing their own goods, except in the case of a few manufacturers who furnished separate returns in respect of their packing departments. The average number of persons employed during the year 1924 at the factories to which the foregoing statement of output relates was 12,211, of whom 11,110 were recorded as operatives and 1,101 as management, clerical, and technical staff.

Packing cases. As regards the great majority of products the work of packing is normally carried out by the manufacturers themselves. In the case of goods, such as cotton and other textile fabrics, however, which are largely manufactured for export, the work of packing and making up for shipment is frequently given out by the exporting firm to packing warehouses where the work is done "on commission" in accordance with the varying requirements of the export trade.

These firms are situated mainly in Manchester and Bradford, and the particulars furnished in the following statement are those returned, according to the Census of Production, 1924, by firms in these cities who pack and make up "on commission" and also include similar work carried out by merchants who purchase goods for resale.

Packing (including making-up of customers' goods)
Other work done____

Total___

Value

£3, 180, 000 17, 000 3, 197, 000

The value shown in this statement does not represent the aggregate value of all packing and making-up work in connection with textile fabrics, the value of such work when carried out by the manufacturer being included in the net selling value of the goods manufactured.

The average number of persons employed during 1924 at the factories to which the foregoing statement of output relates was 8,043, of whom 7,199 were recorded as operatives and 844 as management, clerical, and technical staff.

BOX SHOOKS

Finland, Sweden, Norway, and Latvia have a virtual monopoly of the British market for box shooks; the low transportation charge from these countries, together with the close methods of wood utilization practiced, enables them to stifle practically all competition. Box shooks are imported either rough or dressed, but mostly rough on account of price, and also because of lack of planing facilities in Finland, which country now holds the predominating position.

Both pine and spruce shooks are used, depending upon the product for which the container is intended.

In order to obtain the American customs drawback there is imported from the United States a small quantity of shooks for the manufacture of containers to be returned to that country filled with goods. The quantity, however, is very small, amounting to only 327,760 board feet in 1926.

Generally speaking, the main outlet for shooks is for the manufacture of standardized containers for such products as soap, margarine, sugar, and whisky, and are set up in the factories of the manufac turers of these products.