cal reasons, wish to lay stone or brick pavement between the rails, there would be no particular objection if it be done in a thorough and substantial manner.

Fig. 49 represents a recommendation for a brick pavement. This is substantially the same as that shown in Fig. 48, except that no tie-rods should be used between the rails but at the base upon the concrete beam as recommended for granite. It is very difficult in using tie-rods between the webs to so place the holes that the rods will be exactly perpendicular to the rails, and

trouble always occurs in laying the blocks, whether of stone or brick, between these bars on that account. It also makes an extrawide joint wherever these rods occur, and satisfactory results can never be obtained in that way.

The space between the upper and the lower flange of the rail, on the outside and on the inside, must be filled when a block pavement of any kind is to be used. Untreated and creosoted wood, sand, cement mortar, and specially burned tiling have been used for this purpose. Wood is probably the cheapest, and if the track is to sustain heavy traffic, so that it will require renewal every five or six years, untreated wood will probably be satisfactory; but if it is to remain ten or twelve years, it should be creosoted, so as to prevent decay before the rails will require renewing. Cement mortar gives good results, but is considered expensive and can be used but once. Specially burned bricks have been used with good results, although some engineers object to them on account of their being easily crushed.

Whatever material is used for this filling, the space between it and the blocks and rails should be completely filled with the same filler as that used in the block pavement, whether paving-cement or cement grout, so as to prevent the admission of water around the rail. Whatever the block construction is next to the rail, whether stone or brick, or whether used in the entire pavement or only as a protection to the asphalt next to the rail, the blocks should be bedded firmly in good cement mortar resting on a concrete base, so that they will remain firmly in place without any settlement under travel and be as rigid as the rail itself.

If it be desired to use the wooden-tie construction instead of any of the methods shown above, the ties should be laid on a concrete base and the space between and around them filled with concrete to the required height for the base of the pavement. In such a case, where, in asphalt and in brick pavements, the ties would be almost if not entirely surrounded with concrete, it would doubtless be more economical to use a creosoted tie rather than an untreated one, so as to prevent the tearing up of the concrete to renew the ties, as the untreated tie would require renewal much oftener than the treated one. The extra expense involved, assuming the cost of creosoting to be 25 cents per tie, would be about $700 per mile of single track, but under the conditions mentioned above this expense would be justifiable.

If it be necessary to lay a street-car track in the middle of a macadam road or a macadamized street, the best results would be obtained by the method recommended for stone pavements, the space between the tracks and rails being paved substantially with stone.

In the suburbs of Boston are a great many macadamized streets upon which street-railways are operated. In all of these the trackspace is paved with stone, as well as from 12 to 18 inches outside. On a road, however, upon which there is not much travel good results have been obtained by laying the tee rails with the ordinary tie-construction. The flange of the wheel maintains for itself a groove along the rail. While this will probably require some attention, especially for maintenance between the rails, it will in the end give very satisfactory results.

It seems almost impossible, however, to keep light teams out

side the tracks even on a macadam street; so where the streettraffic is considerable, the best method is, as has been stated, to pave the track-space with stone.

It often happens that it becomes necessary to lay improved. pavement on a street where a street-car track already exists and in good condition, with rails similar to that shown in Fig. 27. In such cases the pavement, whatever its nature, should be laid between rails on the same level as the head of the rail. Otherwise the surface will be bad for vehicles crossing the track. In order to accomplish this without relaying the track with a grooved rail, it will be necessary to lay some foreign material next to the rail to form a groove.

A device to accomplish this, shown in Fig. 50, has been patented

FIG. 50.

by Mr. Buckland in Springfield, Mass. It consists, as is shown in the figure, of cast-iron blocks made to fit over the tram of the rail, and in such shape as to form the required groove. This costs about $2500 per mile of track, and is said to have given good satisfaction where it has been used.

When brick is used for the paving material, specially moulded blocks have been used both on the outside and inside of the rails. When asphalt is used for the paving material, granite toothingblocks can be successfully employed by setting them as headers

against the rail, as heretofore recommended, and bedding them solidly with cement mortar.

In Glasgow, Scotland, where paving material of any kind is laid against the track on each side of the rail, alternating with the blocks is laid a chilled-steel block casting, 4 inches square, and roughened on top so as to give a foothold to horses. The block is cast hollow in order to save material, and the alternating stone block is of the regular size as that used on the rest of the street. This with the rail gives a solid and unyielding bearing to wheeltraffic, and absolutely prevents any ruts forming next to the rail.

Of what importance the subject of track-construction is can be seen from Table No. 71, taken from a report made to the Massachusetts Legislature in 1898, which shows the mileage of street-railways in the principal cities of this country and compared with those of Europe of about the same population.

According to the Street Railway Journal there were 19,213

miles of street-railways in the United States on Jan. 1, 1900, 17.969 miles of which were operated by electricity.

CHAPTER XIV.

WIDTH OF STREETS AND ROADWAYS, CURBING, SIDEWALKS,

WHAT has been said in these pages heretofore has had special reference to that portion of the street between the curbs and wholly in regard to use, not taking into consideration the general appearance of the street. The space between the curb and the property line, however, has as much to do with the general effect. of the street, especially in villages and suburbs, as the pavement itself.

What is the proper width of streets has been an open question for many years, and it cannot be definitely settled as a rule, but the width must be governed by special conditions in each case. The east and west streets of New York City generally are 60 feet wide, while the avenues running north and south are 100 feet wide. In Brooklyn the width varies from 40 to 100 feet according to locality. In Omaha, Neb., the streets in the original city plat were 100 feet wide, with two streets leading from the capitol 120 feet wide. Macon, Ga., probably has the widest streets of any city in the country, those running in one direction being alternately 120 feet and 180 feet wide. These widths are extreme and, while adding greatly to the beauty of the city, are expensive when they require paving, and inconvenient in the business part of the city.

Broad Street, Newark, N. J., is 132 feet wide, with a 92-foot paved roadway.

The distance between the curbs must be established according to the width of the street, the amount of traffic, and whether the roadway is to be occupied by street-car tracks. Different cities. have different principles for establishing these widths; some having a general rule that applies to all streets, others establish an arbitrary roadway for streets of different widths.