Part 3

Macadam has no place in a city street, nor is it wise to lay it on the entire width of a roadway. It best serves its purpose when laid in a comparatively narrow strip, leaving the sides of the road unimproved, except for the formation of earth gutters, so that the surface water can readily soak away where the soil is sufficiently porous.

Macadam is the most expensive of all street surfaces to keep in thoroughly good condition, and in this country it is rarely, if ever, so maintained, except in some of our park roads.

The pavement which is to-day, more generally than any other, superseding stone on all streets where the traffic is not excessive nor the grades extreme, is asphalt. It is scarcely necessary to attempt to give a history of the use of this material, how its adaptability to paving purposes was first discovered by the improved condition of the roads over which it was hauled from the French mines for use in reservoir and tank linings, etc. The drippings from the carts were observed to have been compacted by travel until a smooth, hard roadway resulted. The first street to be paved with it was Rue Bergera, in Paris, in 1854, and it was so successful that in 1858 Rue St. Honore was similarly treated. An asphalt pavement was laid in Threadneedle Street, London, in May, 1869, and in Cheapside and Poultry in the fall of 1870, while in Berlin its use began in 1873.

The laying of bituminous pavements in this country began in 1869, and they were first made of tar concrete, or Scrimshaw. Asphalt began to be used within the next year or two, and its popularity has been astonishing, as will be seen from the fact that on January 1, 1898, the area of this kind of pavement laid in the United States was, as nearly as could be ascertained, thirty million square yards.

There is a notable difference between the European and American asphalts. The former may be called natural and the latter artificial pavements. In the former the material, as it comes from the mine, is ground to a powder, heated, placed upon the foundation prepared for it, and tamped into approximately the same condition as before it was disturbed, though usually the product of several mines is mixed in order to obtain the best percentage of bitumen, but nothing is added to or taken from the bituminous rock. In the pavement usually laid in America, on the other hand, only a small proportion of the material is brought from the asphalt deposits, the principal part of it (sand) being obtained near at hand. In the one case the cost of long ocean or rail transportation has to be paid on the entire mass forming the pavement, while in the other this expense attaches to but from twelve to fifteen per cent of the material. This, of course, is a great advantage, and at recent prices it is scarcely possible for the European rock asphalts to compete with the artificial ones.

The making of a pavement from one of the standard asphalts may be briefly described as follows: The material as found in Nature has this composition:

Bitumen 38.14 per cent. Organic matter, not bitumen 7.63 " Mineral matter 26.38 " Water 27.85 " ------ 100.00

This is cooked until the water has been driven off, and some of the mineral matter has settled.

The above analysis is of Trinidad Pitch Lake asphalt, and is a particularly favorable result. This material is too hard for use in making a pavement, and it has to be softened or fluxed by the addition of something which will accomplish this purpose. In order to do this there is usually added to each one hundred pounds of refined asphalt about eighteen pounds of heavy petroleum oil. After this addition we have the asphaltic cement ready to combine with mineral matter, which is so selected that when asphaltic cement is added at the rate of about seventeen pounds of the cement to eighty-three pounds of the other all the particles will be coated, and more could not be added without making the pavement too soft. What is found to accomplish this best is fine stone dust and sand.

The asphaltic cement and sand are heated separately to about 300° F. The stone dust is then added to and mixed with the hot sand in the proportion of from five to eighty in the case of fine, well-graduated sand, to fifteen to sixty-seven for coarse sands, having less variation in size. The asphaltic cement is then added, and the materials are mixed to a homogeneous mass, which is ready to be taken to the street. It should reach there at a temperature not less than 250°, and is spread with hot iron rakes so as to give usually a thickness of two inches after consolidation. After spreading, it is rolled with a hand roller, after which a small amount of hydraulic cement is swept over the surface, and it is thoroughly rolled with a steam roller of not less than ten tons, the rolling to be continued as long as the roller makes any impression on the surface.

The foundation is usually of cement concrete about six inches thick, though asphalt pavements are often laid over old stone pavements. Between the foundation and the wearing surface there is generally laid what is called a binder course, one inch thick and formed of small broken stone, to which has been added asphaltic cement, the same as is used in making the wearing surface. Five or six pints of this cement are used to each cubic foot of stone.

The pavement just described is made from Trinidad asphalt, the material from which nearly all the earlier artificial asphalt pavements in this country were made, and which was used almost exclusively until within the last half dozen years.

Within that time, however, it has been discovered that there are a number of other deposits of asphalt well adapted to use for street pavements. A very large deposit containing a high percentage of bitumen and very little mineral matter is located near the coast in the State of Bermudez, in Venezuela. Large deposits have been found in several places in California, and in Utah, Kentucky, and Texas, and a number of other places. The Kentucky product is classed as a natural rock asphalt, as it is a sandstone impregnated with bitumen. It has been mixed with about an equal portion of German rock asphalt and used with very satisfactory results in Buffalo. These asphalts are quite different in their composition, and each requires somewhat different treatment. The Bermudez, being richer in bitumen and softer, requires the addition of very little flux. The California deposits furnish their own flux in a liquid asphalt or maltha, which is almost absolutely pure bitumen, and the use of petroleum residuum is thereby avoided altogether.

It has been recognized since 1836 that the bitumen which forms the greater part of natural asphalts can be separated into two substances, which have been commonly known as petrolene and asphaltene, the former of which possesses the cementitious qualities essential to the making of a successful pavement. Instead of the arbitrary names--petrolene and asphaltene--these substances are sometimes more aptly designated as active and inert bitumen. It has been found that of the bitumen extracted from asphalts which have given the most satisfactory results in making street pavements, sixty-nine per cent or more is soluble in petroleum naphtha having a specific gravity of 72° Beaumé.

An asphalt pavement can not be economically kept in good condition unless every defect which may develop is immediately repaired. When the smooth, hard surface is once broken, disintegration proceeds very rapidly, and a large hole is soon formed. The more general distribution of smooth pavements, however, will tend to distribute the traffic more evenly, and the increasing use of rubber tires and rubber shoes for horses, to say nothing of the probably quite general use of motor vehicles, within the next decade will result in the elimination of the forces at present most destructive to pavements.

Much regret is often expressed that asphalt pavements should be so frequently opened for the purpose of laying or obtaining access to subsurface pipes and conduits, and thereby mutilated. As a matter of fact, there is no pavement at present in use which can be so effectively and satisfactorily restored as asphalt. When skillfully done, almost no trace of such an opening can be found.

The first question to arise, when it has been determined to pave a street, will be the selection of material, or the kind of pavement to be laid. In determining this, the governing considerations will be the traffic to be sustained, its density and character, the rate of grade, and the presence or absence of railroad tracks.

If the traffic be very heavy and the street given up wholly to business, ease of traction, durability, and economy of maintenance are of first importance, while quiet, comfortable riding, and beauty can be sacrificed to them. Many efforts have been made to determine the relative force required to draw a load over different kinds of surface under similar conditions. The following is from a table compiled by Mr. Rudolph Hering, from different authorities, the force being that necessary to move one ton on a level grade at a speed of three miles an hour:

KIND OF ROAD. Pounds.

Ordinary dirt road 224 Ordinary cobblestone 140 Good cobblestone 75 Common macadam 64 Very hard, smooth macadam 46 Good stone block 45 Best stone block (London) 36 Asphalt 17 Granite tramway 12½ to 13½ Iron railway 8 to 11½

The question of durability occurs next, and the different kinds of pavement which may be considered for city streets may be rated as follows, it being assumed that the traffic is not excessively heavy:

KIND OF PAVEMENT. Life in years.

Best granite block on concrete 30 Granite block laid on sand 20 Belgian trap 20 Cobblestone 18 Asphalt 15 Best wood--rectangular block 10 Vitrified brick 12 Macadam 8 Cedar block--round--on sand 5

No class of municipal work comes so near to the daily life of an urban population--both the business and the home life--as the surface improvement of city streets, and no expenditure is too great (provided the work is skillfully and honestly done) to make them smooth, clean, sanitary, and beautiful.

TYPICAL CRIMINALS.

BY SAMUEL G. SMITH, LL. D.

If the question of a criminal type, defined by certain marks of a physical nature and emphasized by accompanying mental and moral characteristics, were confined to the technical speculations of a special craft of scientists, the public would have little interest in the spread of the doctrines of Cesare Lombroso and his _confrères_ in this country. When it is believed, however, that certain men and women are committed to prison or condemned to death not on account of crimes in any ethical sense, but because of spontaneous actions from vicious impulses beyond their control, the subject affects the administration of law, the theory of punishment, and the safety of society.

Lombroso and the Italian school say that they have discovered a type of man who is born a criminal, and who may be recognized by a Mongolian face, abnormal features, ill-shaped ears, unsymmetrical skull, and various psychical peculiarities, which are the result of bad organization. This doctrine is illustrated by descriptions of criminals who have the abnormalities, and in the hands of skillful writers the case is made very plausible. The theory is in harmony with so much popular modern thought, which loosely interprets the doctrine of evolution by a crass materialism, that it has infected American prison literature, while it has never misled those men to whom practical experience has given the most right to have an opinion on the subject. The sense of personal responsibility is still the foundation of social order, and if in truth there is no such thing, the world is awake at last from its dream of morality; righteousness is resolved into heredity, structure, and habit; living is a mere puppet show, and the wreck of things impends. If Lombroso is right, modern scientific methods are sure to prove him so, and we shall have at last sound theories; but we shall have no world in which they can be used, for the dissolution predicted by Herbert Spencer will have come.

Exceptional opportunities for the study of the abnormal classes in the institutions of this country and Europe have given me a personal interest in the question of the criminal type. I have discovered that the criminal anthropologists do not choose for comparison with the prison population their normal men from the ranks where the criminal classes are recruited. Blackwell's Island has no more peculiar inmates than abound in sections of New York near the East River; the residents of the Whitechapel district of London may be compared with the inmates of Pentonville, to the distinct credit of the latter; and the man in Roquette is no worse off in body than scores whom I have seen in certain localities south of the Seine. The fact is, no human body exists which is not in some respects abnormal. The number of abnormalities and their extent depend upon a variety of circumstances, among which are food, climate, occupation, and the incidents of birth itself, as well as the various forms of infantile disease. I will undertake to find enough physical peculiarities, in any locality, or among the members of any profession, to establish any physical theory which may be propounded.

It occurred to me to try an experiment in a manner entirely different from the usual criminal researches. Having been very familiar with a certain prison for many years, I requested the warden, who is a very able man in his profession, to send me the photographs of ten or a dozen men whom he regarded as the most representative criminals in his population of some five hundred persons. The warden was not informed of the use I intended to make of the material, and supposed it was for illustration in university class work. Later, he gave me the Bertillon measurements of the men, with an epitome of their history. A number of these men I have known for years. So far from this selection supporting the modern theory of a criminal type, it confutes it in a conspicuous manner. The abnormalities are slight, and there is as great a diversity among the men as could be asked. It must be remembered that these cases were selected by a shrewd and competent official, solely upon their criminal record, and not in the interests of any theory whatever.

Of course, the men do not look well, but neither would any ordinary company of citizens if their heads were shaved and they were put in prison dress. I am always shocked by the changed appearance of the men after the prison transformation. Young embezzlers of elegant figure, who have moved in good society without a question, easily look the rascal behind prison walls.

The first group are murderers. No. 1 murdered his daughter because she insisted upon going to a party against his wishes. He has the head of a philosopher. It was his first crime. It may be noted that tattooing is supposed to be common among criminals. This man is tattooed, but committed no crime until fifty years of age, and was a deputy sheriff for some years. No. 2 did not kill his victim, but the assault was murderous, and the escape from death was accidental. It is difficult to discuss the negro in crime without entering into racial and social questions beyond the present limits. No. 3 has a very good head, an excellent ear, and, barring the expression, a pleasing face. He has a life sentence for murder. He is the worst man in the prison. I have for years believed him to be insane. His family is criminal. His father murdered his mother in a brutal manner before the child's eyes, when No. 3 was only eight years old. He himself has committed several desperate assaults, growing out of his persistent mania of persecution. No. 3 is not morally responsible, and there are usually two or three such prisoners out of a thousand subjects.

The second group are very diverse in structure and temperament, but have committed the same kind of crime. No. 1 is a confidence man and a forger. He is a crafty and an habitual criminal, has served terms in various prisons, is keen of intellect, well educated, has traveled in many countries, and is a citizen of the world.

No. 2 is a confirmed forger, and has served several terms in prison for the same offense. He is a skillful bookkeeper, has an attractive manner, and as soon as he is out in the world secures employment and plans his next crime.

No. 3 is a counterfeiter. His head is small, but of excellent shape, and he has rather a refined physical organization. His criminal record is bad, and he has served at least one term before for the same offense. His imagination, temperament, and vices would select him as a person who would be guilty of a very different and more fleshly kind of crime. The group is formed by the correlation of crime; they have nothing in common in physical organization.

The third group are thieves. No. 1 is a confirmed criminal, and has served several terms in prison. He is the tallest man in the list. His head is "long" and well formed, and his features are regular. His expression indicates power of sustained thought, and his peculiar appearance is not due to his kind of crime, but to his habit of mind. He is a pessimist of the first rank, and hates the world, his fellow-men, and perhaps himself most of all. He will not work when at liberty, thinks that society is totally depraved, and that war upon it is the only proper mission in life. He is pre-eminently the antisocial man.

No. 2 is really a pleasing fellow. He is tender, sympathetic, and pious. Under proper circumstances he might have made an admirable Sunday-school superintendent. He is plausible, insinuating, and winning. In temperament, feeling, and social habit he is the complete antithesis to No. 1. He is a most dangerous criminal, and has a black and varied record.

No. 3 is a man of lower grade of organization and habit, but he is a criminal by profession. He is an idle and worthless vagabond, but he is an accomplished thief. He makes an excellent prisoner, obedient to the rules, industrious, and seemingly anxious to improve. In fact, the prison furnishes his best environment, for it is only there that he is at peace with himself and his world.

The last two men presented are contrasts. No. 1 is an accidental criminal. His previous history and character give strong grounds for the belief that, under pressure of want for the necessaries of life, he was led astray by a man older and stronger than himself. It is not likely that he would repeat his fault. No. 2, on the other hand, is a sexual pervert of the worst kind, whose case seems so hopeless that perpetual imprisonment is indicated as the only relief for him, and the only safety for society. Apart from the expression of his eyes, caused by an irregular focus, there is nothing marked about the face. The head is of a pronounced "broad" type, but, on the other hand, he comes from a province of Germany where that type is dominant.

To complete the experiment, I submitted these portraits to a number of gentlemen, and to no two of them at the same time, for their opinions of the cases. The informal committee represented the different professions which might be expected to fit men for observation, for there was a lawyer, a physician, a railway president, a criminal judge, and a college professor. Each of them is eminent in his special field. The committee was manifestly handicapped by the shorn head, the prison dress, and the lack of the accessories of masculine ornamentation, such as collars and cravats. The committee was asked to name the crimes, and to group the men according to their criminal record. Each opinion differed from the other, and all were wide of the mark. The shrewd lawyer thought the accidental criminal "might be guilty of anything." It was only the college professor, the last man of the company from whom anything might properly be expected, who was able to select the worst two cases with the remark, "These men are degenerates." But while the committee was at work on the photographs the writer was at work on the committee, and actually discovered more anomalies of organization in these distinguished citizens than are apparent in the criminals. After this remark it is necessary to withhold their names, though some of them are men of national reputation.

It is time to reassert with increasing emphasis the personal responsibility of the individual, and to insist upon the enthronement and guidance of conscience. There are certainly social and economic reasons for crime, some of which the writer has pointed out elsewhere, but the chief fact in human life is the power of self-determination. The chief causes of crime, outside of personal and moral degradation, are psychical and not physical. The reader of history can not fail to have noted that relation of prevalent ideas to conduct which is so conspicuous in human affairs. The scenes of blood and desolation characteristic of the French Revolution are directly traceable to the doctrines which prepared the way for anarchy, but not for rational freedom.

We have had our attention directed to the contagion of suicide which has marked the last half decade. But Lecky tells us that suicide was made practically unknown in the civilized world by the spread of Christianity and its beliefs in the dignity and sanctity of man. The present contagion will disappear not as the result of food, or raiment, or houses, or any other material good, but by a revival of practical faith in the human soul and its capacity, in human righteousness and its obligation.

A CENTURY OF GEOLOGY.

BY PROF. JOSEPH LE CONTE.

[_Concluded._]

THE AGE OF THE EARTH.