Speed Governors for Motor Trucks: THEODORE DOUGLAS.

There are various types of governors available of which about 95 per cent. are of the centrifugal variety. The constant-engine-speed governor ties up from 20 per cent. to 50 per cent. of the power capacity of the engine and sacrifices both gasoline and engine efficiency. The constant-vehicle-speed governor regulates only the vehicle speed and sacrifices the engine through allowing a prohibitive speed on low gears, and no control at all in idling. It is shown that the ideal governor would be a combination of the constant-engine-speed and the constant-vehicle-speed governors. A governor of this combination type is now available in the industry.

This governor may be broadly described as a combination of two-speed controls operating a single centrifugal unit and actuating a single valve. This is accomplished through the employment of two springless pawl clutches so designed that each may overrun the other. Whether the speed from the engine or from the vehicle is the higher speed, that speed will engage the centrifugal unit and close the valve.

By the use of the combination type governor, truck efficiencies have been largely increased, and a perfect automatic control has been supplied. Factors controlling Maximum Overall Dimensions of Motor Trucks: ALFRED F. MASURY. Traffic Census Analysis: WILLIAM H. CONNELL. In order to work out a suitable highway design, it is necessary to make a study of the traffic conditions, and upon the collection of adequate data and its careful analysis may be based: (a) the plan of a highway with respect to its lines, grades, widths and location of roadways, footways and lawn areas; (b) the design of a pavement surface and base best suited to the traffic requirements; (c) an estimate of the probable relation between traffic service and maintenance costs; (d) the character and time of cleaning best suited to the prevailing types of traffic; and (e) the physical regulation of traffic with respect to the direction of flow, crossings, parking areas, safety islands and zones, and safety and regulating signals.

The several lines of investigation which are necessary to a comprehensive traffic study may be indicated as follows: (a) the survey, which determines the nature of the existing physical and other conditions influencing or relating to the traffic; (b) the census, which records. the quantity, character and weight of traffic; and (c) the planning, through which it is sought to develop a more con

sistent relation between traffic requirements and traffic provision.

In most traffic census, it has been the general practise to consider "ton of traffic per foot width of pavement" as a proper unit. It would seem that the most logical and satisfactory unit of traffic measurement would be the "ton-mile" or its multiples per foot of maximum travelled width of pavement.

The Most Satisfactory and Economical Pavement for Parkway Drives: SAMUEL WHINERY. Present Status of Preliminary Location and Mapping of National Highways proposed by the National Highways Association: CHARLES HENRY DAVIS.

Possible Variations of Physical Properties of Rock from One Quarry: CHARLES P. BERKEY. Stone and Concrete Foundations from the Standpoint of Efficiency and Economy: GEORGE C. WARREN.

The words "Efficiency and Economy" each in their broadest sense mean practically the same thing and the same as the word "best," when considered in its broadest sense of "all things considered.''

There is no one "best" for all conditions and an engineer who would recommend any one type of pavement surface or foundation as universally best, would be like an architect who specified one class of building material as best for all buildings, i. e., a "man of one idea."

In determining the character of foundation best suited for any particular case, the engineer or roadbuilder should give most careful consideration to the character of subsoil, traffic, wearing surface to be laid on the foundation, and climatic conditions. Block pavements of all kinds should be almost universally laid on concrete foundations. lithic bituminous pavement surfaces depending on stability of the surface and local conditions outlined above, may be laid on either rolled broken stone or concrete foundations.

Mono

Concrete includes any dense combination of mineral aggregates in which the coarser sizes predominate artificially bound together with either Portland, bituminous, or any other type of cement.

Generally speaking, broken-stone foundation is adapted for cases where the rolled subgrade is of a character of material which can be solidly compressed. It has been found that sand provides a good sub-base provided the sand is sprinkled during the rolling of the broken stone, thus providing a sub-base condition like damp sand on the beach.

Concrete foundations should be used on weak subsoil of clay, etc. Portland cement concrete roads and foundations crack, causing corresponding cracks in the pavement surface, which is retarded by the use of either broken stone or bituminous concrete foundation. Bituminous pavement surfaces are more liable to creep on Portland cement concrete than on broken stone or bituminous concrete foundations, as in the latter cases the surface and foundation are firmly united to each other. Portland cement concrete foundations should be used where a maximum rigidity is essential.

Present Status of Bituminous Surfaces on Gravel Roads: JOHN R. RABLIN.

Value of Physical Tests on Bituminous Aggregates: PREVOST HUBBARD.

Proportions of Ingredients of Bituminous Mortars Used for Fillers: PHILLIP P. SHARPLES. Bituminous mortars used for fillers in block pavements have been used in the United States of America since 1913. These fillers consist of mixtures of coal tar pitch and sand, or asphalt and sand. Specifications for both kinds were adopted at the 1916 meeting of the American Society of Municipal Improvements.

These bituminous mortars are particularly well adapted for use in filling the joints of stone block, brick, lug wood block and Durax pavements. Observation shows that the asphalt-sand mastic does not fill the joints as well as the pitch-sand mortar, owing to the higher melting point of the former and its lower adhesive value.

Summary. Those bituminous mortar fillers that have given trouble to date have done so because not sufficient sand was originally mixed with the bitumen. A fine sand gives much better results than a coarse sand, and more of it can be introduced in the mastic. By properly heating and applying, a mastic with equal parts, by volume, of sand and bitumen can be forced into the joints of block pavements. For special conditions, special grades of bitumens must be used. Hand mixing is cheaper than machine mixing, and as good. The pouring method should be entirely dispensed with and the flushing and squeegeeing method substituted.

Present Status of Physical Tests for Granite Blocks: C. D. POLLOCK.

This paper gives the progress made in tests of granite for paving blocks and reviews the changes made in such tests in standard specifications which have been in very general use.

Even the latest tests are far from ideal, as the

conditions which prevail in the tests do not approximate those which exist in actual traffic on the pavements.

Engineers are now studying this question and undoubtedly will work out some tests which will more nearly conform to the wear and tear of the traffic on the granite block pavements in the

street.

The service test at the present time is the only sure and reliable test.

Joint Fillers for Granite Block Pavements: HERMAN H. SCHMIDT.

In this paper the development of the granite block pavement is traced from the first granite pavement laid which resembles our modern granite pavement, up to the present highly improved granite pavement, as laid in our large cities.

A detailed statement of the requirements of ideal joint fillers is given, followed by a discussion of the various joint fillers used and available. In this discussion the defects in each are pointed out, and the writer suggests what in his estimation would be an ideal joint filler.

There is also a brief discussion of methods for applying joint filler, and mention is made of the character of the cushion course which will give best results.

The writer's conclusion is that with slight changes in the methods of work and improvement in the character of joint filler, granite pavement will have reached the highest state of development of which it is capable.

The Real Sources of Trouble in Brick Pavements: MAURICE B. GREENOUGH.

The most common imperfections in brick pavements are caused by non-enforcement of adequate specifications reflecting the best procedure of modern methods. One hundred per cent. construction is not possible of attainment under some specifications in force which are indefinitely worded and incomplete. Few imperfections are caused by brick of poor quality. The American Society for Testing Materials has adopted procedures which, if followed, insure securing the required degree of quality in the brick. Monolithic construction, while not a panacea for all brick pavement troubles, eliminates the hazards of a faultily prepared sand cushion and affords a large measure of protection against most brick pavement imperfections.

PERSONALITY AS REVEALED BY THE CONTENT OF IMAGES 1

CHARACTER study and the investigation of personality have recently assumed, on account of the present tendency to apply psychology, a psychological importance they did not formerly possess, and since it has given rise to a general interest in any work looking towards the possibility of getting additional information regarding the individual consciousness, it has seemed to me I could not do better to-day than to outline the results of an investigation which I have made to ascertain whether it is possible through the examination of the content of an individual's images to obtain an insight into the predominating features of his personality, that is, the psychical and physical activities which characterize and distinguish him from others.

The experiments were made with 20 persons, largely professors and students connected with the Stanford University. In half of these experiments (S.) the observers allowed visual images to arise of themselves and in the other half (V.) they aroused them. It is scarcely necessary to add that the experiments were "unwissentlich."

The most important fact that comes out in examining the tabulated results and what was given to protocol is that visual images reveal the mental and physical peculiarities and preferences of an individual.

In what follows, I shall take up in detail the results of but 3 observers, to show that the data ob1 Address of the vice-president and chairman of Section H, Anthropology and Psychology, American Association for the Advancement of Science, New York meeting, December, 1916.

tained reveals the observer's personality, that is, his mental and physical activities as shown by what has been stated concerning him in "Who's Who in America" (W.), "American Men of Science" (C.), his general reputation in the university community, the opinion that his intimate friends have of him, my own knowledge of him, and by what he himself said at the close of the experiments when questioned regarding the personality-revealing power of the content of the images he had reported.

The first individual results to which I wish to direct especial attention are those obtained with R.-(C.W.)-professor of electrical engineering at Stanford University, formerly at Cornell. Born in 1866. Has not traveled in Europe. At the time of the experiments was preparing for a demonstration and discussion at the approaching summer meeting of the American Association for the Advancement of Science of the insulation of electric currents at high voltage.

R.'s images for the most part as regards frequency follow the general time law. The interesting peculiarities to note are that the willed images have, more frequently than the spontaneous, an imaginative character, and that the future gives more images in the case of willed images than of spontaneous. That is, the imagination images are concerned with the future; they have a creative rather than a reminiscent character and have more largely to do with electrical work. The difference in content between the spontaneous and willed images of R. is due doubtless to the course of training as regards the putting aside of his electrical and, indeed, of all work of an inventive character during the hours devoted to rest, which he has been obliged to give himself in order to restore and preserve his health.

R.'s images are connected with the east, where he has engaged in electrical work, with Stanford University, especially his laboratory and home, with the Panama-Pacific Exposition in San Francisco, with Owens Valley and La Jolla, where he watched the construction of the Los Angeles Aquatic Power Project as consulting electrical engineer, and with places where he has gone on pleasure excursions in his automobile, as, for example, a series of views on a drive from San Francisco and San José to Stanford.

People, interiors (his own laboratory, particularly), electrical instruments and machinery, automobiles, electric cars and landscapes, especially the scenes along a country road, are evidently of the greatest interest to R. It is noticeable that

when he uses his will, not people or landscapes are the image-producers, but his work as an electrician, the improvement and adaptation of electrical instruments and machinery that he contemplates taking up in the near future in getting ready for the demonstration just mentioned.

Through curtailed summary just given of the content of R's images I am able to give but a very general idea of the information conveyed through them regarding his mental and physical activities. The results, however, obtained with him and with the other observers do show that through using the image method one is able to obtain very detailed information regarding a person's individual peculiarities.

W.-Major in history, Stanford University. Born 1890 in Los Angeles, where his family has since lived. Captain of the baseball team. Visited Japan and Hawaiian Islands with the team in 1913. The experiments were made during the baseball training season.

W.'s spontaneous images are largely confined to the present and to Stanford University. Those that are willed also include images of the trip he made with the team. His Stanford images show that his thought is taken up with the men of the baseball team, the athletic field, the training house, and with other places and things connected with the playing of baseball. The images give, without doubt, a true picture of the life of a college student devoted to athletics. It is said this observer has been tempted to give up the idea he formerly had of going into scientific farming and has even seriously considered devoting himself to professional baseball. One is made to realize more fully in examining these images how college athletics may largely absorb a student's thought and become, as in this case, a menace as far as the particular student is concerned to the college itself as an intellectual center.

FF.-Born in Palo Alto in 1901 and has lived there continuously, except for a year and a half spent in the eastern part of the United States and the eleven summers of perhaps four weeks each, spent at Carmel, and the four summers of eight weeks each at Tahoe. Up to within a year or so she studied at home, but is now in a private school.

As to time, FF. 's images follow the law, except that their number is greater in 1909-07 than in 1911-10. This is probably due to the fact that a year and a half of this time was spent in the eastern part of the United States, for the majority of the images of this period are reproductions of occurrences connected with this eastern visit.

As to location, FF.'s images have to do with Palo Alto (her home, school, etc.), the places where her summers have been largely spent (Carmel and Tahoe) and with the experiences, as was said, of the year and a half residence in the east. The year in the east, considering the time involved, has a very much greater image-producing power than has her own home in Palo Alto. The same is true of her life at Carmel and Lake Tahoe, the last furnishing more images than does Carmel, where she spent more time and the time was more distributed. The importance of vacation periods in the intellectual life clearly comes out here, as well as in case of some of the other reagents.

I suspect the pleasure-giving power of an image often determines its arousal in FF.'s case. At any rate, no image of her experiences at Carmel in 1906, when she had scarlet fever and suffered a great deal, arose, and moreover, every one of her images has an agreeable content and she showed much pleasure in describing them. Not only pleasure, but the newness of an experience is also, doubtless, an important factor as regards its being imaged. This explains probably why FF. reproduces in her images so rarely the members of her own family, to whom she is devoted. One must not, however, over-emphasize pleasure and interest as image-producing factors in her case, for the results show other factors often enter in and control their arising. For example, FF. went to the Exposition two days during the time the experiments were being carried on and was greatly interested and took much pleasure in what she had seen, but the fifteen images recorded after her return from the Exposition do not reproduce what she saw there.

FF.'s predominating interests are evidently those enumerated by her mother, before she knew the distribution of her images-Tahoe, Carmel, people, school, horses, in fact, all animals, plants, especially flowers, water and landscapes. Some of the images classed under people had a landscape background or were accompanied by another imagearousing subject such as an animal; a person, for example, was on horseback, or a dog or cat was with a person, but such images as to content have been classed under people, because it was quite evident that the person or persons were the real centers of interest. That FF. is a close observer, as her mother says, is evident from the presence of details in her images which most persons would not have noticed in examining the particular object visualized, as for example, the way in which

the sunlight fell upon certain parts of a dress, was reproduced in them.

A comparison of FF.'s images with those of her brother LF. shows that her visualizations are much more personal and in general less valuable as regards content. LF. for example visualized Lake Michigan, an aeroplane at the Exposition, the plains in New Mexico, scenes described in a book on the south pole, speed boats at the Exposition, views of Pittsburgh, a glacier, picture of Whistler, harbor at Sandusky, etc. FF. Gertrude Jones on her wheel, Mrs. Jordan at a picture, Dr. Lane shooting at little cans, Mrs. Ely with a rose in her hair singing, etc. As FF. is an intelligent girl, it is probable that the unimportant content of her images is due to her secluded education and the greater emphasis laid by those who have had to do with it on the less important matters of life. What is true of the content of FF.'s images is also true of the images of the other girls who took part in the experiments.

The results with FF. show very clearly the diagnostic significance of these experiments from an educational standpoint. FF.'s mother, with whom I studied the results, I found later, had made an application of what she had learned. FF.'s reading had been altered and family discussions were now more often connected with matters of world interest.

The results also show that visual images reveal the attitude of an individual as regards the world around him. The activities pictured in the image and the observer's relation to such activities show whether he is a participator, an actor in the scene, or only an observer of it, that is, whether an objective or subjective attitude of mind marks him.

Before leaving the discussion of the general facts it ought to be said, perhaps, that the results do not show that a study of a person's visual images alone, even where such images are very strong and detailed, will completely represent his personality. To obtain such a representation, as well as to determine the laws of thought in general, not only must the content of other images, as the tactile, auditory and kinesthetic, be studied in themselves and in a comparative way but the relative signif