Part 8

The next step is to study these products of deposition in their consolidated forms. At Parker Hill, Roxbury, a large quarry furnishes opportunity for the study of conglomerate, special attention being paid to the means of determination of stratification in a nearly homogeneous, coarse material. Here also is a large section in a drumlin left in a nearly vertical face by excavation about twenty years ago, and now illustrating finely the action of rain during the years. This forms an instructive contrast with the marine erosion of Great Head, Winthrop. Any one of the numerous slate quarries at Somerville serves the purpose of studying stratification in a fine, homogeneous material. In each of these three last-named places the various phenomena of stratified rocks are studied, such as unconformity, cross-bedding, ripple-marks, strike, and dip, but attention is confined more especially to the original structures, subsequent structures being left for later lessons.

Eruptive rocks are then taken up and studied in respect to their origin and original structures. The quarries near Winter Hill, in Somerville, furnish an admirable opportunity to study dikes. Here a small hill of slate is intersected by three series of dikes of different character and intersecting each other at various angles, enabling a determination of their relative ages. An intrusive bed, now separated from its parent dike by erosion, affords the means of comparing the characteristics of the two forms and of tracing out the relation between them. The inclined positions of the dike and bed and the numerous quarries furnish several sections in varying relations to the two. The various dikes and the inclined position of the inclosing slate give an excellent chance for the first instruction in the making of geological maps and sections. Notes are taken for this purpose, and both maps and sections are constructed and handed in at a later date.

At Marblehead Neck various other eruptive structures, such as flow structure, ancient ash-beds, etc., are seen in the felsite, of which many varieties occur there. Attention is especially called to the liability of mistaking flow structure for stratification, the similarities and differences being explained. At Marblehead Neck, also, a careful study is made of the formation of pebbles, all stages being shown from the dislodging of fragments from the cliffs by frost action, the dropping into reach of the waves, the first rounding of the sharp angles to the subangular outline, and finally the rounding of the fragment into a complete pebble form.

At Newton Centre a study of contemporaneous beds is made, including their relations to the inclosing rocks and a comparison of their characteristics with those of intrusive beds.

Eruptive masses, metamorphic rocks, and vein phenomena are all well shown at Fitchburg, where Rollstone Hill is an eruptive mass of granite cutting through the metamorphic mica schists and gneisses, and the granite in turn is cut by very numerous veins of pegmatite, abundantly rich in tourmaline crystals and occasionally having beryl.

Glacial structures are next taken up. At Newtonville is studied the esker and sand plateau, rendered famous by the work of Prof. W. M. Davis and others; at Clinton an exceptionally fine set of terraces, and the best example of _roches moutonnées_ near Boston, where a class can be taught in a very few minutes to recognize that the movement of the ice sheet must have been from the north toward the south; and at Stow and Haverhill are studied drumlins.

After this, special attention is devoted to the subsequent structures of rocks, such as folds, faults, cleavage, joints, etc. Typical places, as before, are selected for each, and the work carried on in the same manner. When this course has been entirely accomplished, then places of greater complexity and where the problems are not quite so plain are visited, and opportunity is given to exercise the skill or knowledge already gained.

Following this, a series of lessons is devoted to the study of typical places illustrating the various historical strata occurring in Massachusetts; among others, Nahant and Braintree for the Cambrian, Attleboro for the Carboniferous, Mount Holyoke for the Triassic, Gay Head for the Cretaceous and Tertiary, Rockport, Martha's Vineyard, and claypits of Cambridge for the Glacial Champlain.

The work in this course has been marked by enthusiasm, and the attendance has been very large, reaching a maximum of two hundred and ten, with an average attendance of seventy-one in the autumn of 1896. As a direct outcome of this work, and connected with it, several excursions to distant points have been made by parties under the charge of Professor Barton during the summer vacations. The most important of these were the following: A five-days' trip through western Massachusetts; a seven-weeks' trip to the Pacific coast, including visits to the Lake Superior copper regions, the Yellowstone Park, Butte, Montana, Great Shoshone Falls in Idaho, Columbia River, Mount Hood, Frazer Cañon in British Columbia, the Great Glacier of the Selkirks, and the Hot Springs at Banff; and two trips through Nova Scotia, one in 1894 and another in 1898. In each of the latter trips special attention has been paid to the various kinds of mining coal, iron, and gold, to the famous mineral localities like Cape Blomidon, and to the general geology.

Also, connected with this work, a special course of lessons has been given by Professor Barton each spring to a class from the Boston Normal School, and many occasional lectures and field lessons to the classes of the State Normal School at Framingham, and at other schools, teachers' clubs, etc. During the Boston exhibition of the cyclorama of the volcano of Kilauea, Hawaii, over three hundred teachers and a large number of schools visited that exhibition and listened to personal lectures by Professor Barton in direct connection with the work of The Teachers' School of Science.

Owing to the request of members of the field class, a private class was organized in the winter for a course of twelve lessons in mineralogy. This proving successful, and a demand for laboratory work being shown, this work was incorporated as a distinct course in the school. It was during the early part of this work that Professor Barton introduced for the first time in The Teachers' School of Science the system of daily and final examinations--a system since followed as the general practice of the school and now considered as one of its most fundamental features.

This course, after various experiments, has finally developed into a definite four-years' course of instruction, at the end of which those members who have met all the requirements receive the diploma of the school. The full four-years' course is designed to give a thorough training in the fundamental principles of geological science. Each year is given a series of fifteen lessons of two hours each, partly laboratory, partly lecture, and fully illustrated with specimens and diagrams. The first year's work is devoted to mineralogy. One introductory lecture is given on the principles of chemistry as the basis of understanding the composition of minerals, and the four following lessons are devoted to a study of the physical properties, mainly crystallography. During the remaining lessons, about one hundred and fifty of the commonest mineral species are studied, the class being required to learn to recognize each species and be able to tell its composition.

The second year's work with lithology is carried on largely in the same way as with mineralogy. At first a brief review is made of the most important rock-forming minerals. Then all the commoner species of rocks are taken up and studied, so as to learn to recognize each species at sight and to tell its composition. Besides this, lectures are given upon the origin of the rocks and the derivation of their component materials, involving a large amount of dynamical geology.

During the third and fourth years are taken up, respectively, structural and historical geology. Both these subjects are taught largely by lectures, illustrated by charts and diagrams, a select set of specimens for the table, and a few such specimens as can be passed around the room. In the historical geology special care is taken to furnish for class use as many specimens as possible of the typical rocks and fossils of the various ages. It is nearly impossible to provide so abundantly, however, as for mineralogy and lithology. As regards examinations, the methods used are as follows: The first half hour of each exercise is taken up with answering questions or identifying specimens, the examinations in all cases being written. The ground covered by each examination includes all that has been gone over during that year previous to the examination. After the examination is finished, the instructor briefly answers and explains the questions. The papers so handed in are marked by the instructor and returned the following week. All of this serves to enable the class to keep a comprehensive grasp of the subject constantly in hand. At the end of each year's work a final examination of three hours in length is given, covering the complete subject. The final rank given each member is made up equally from an average of the term's work and the final examination. This course has proved decidedly popular. The instruction was originally given in the Geological Department of the Institute of Technology, in a room adapted to seating thirty-six persons. This was gradually crowded to accommodate fifty-six persons. At the beginning of the last four-years' course the number of the applications was so large that each applicant was required to sign a printed statement promising to be present at all exercises for the four years, except for good and sufficient reasons. One hundred and seventeen persons gave the required promise. In order to meet this demand, two divisions were formed, and on each Saturday afternoon the same lesson was repeated. In order to defray the additional expense of the second division the members of the class voluntarily contributed three dollars each. The labor of repeating the lessons on the same afternoon proving too great, provision was made the second year to transfer the instruction to the large lecture hall of the Natural History building, where accommodations were made for one hundred and twelve students. The work has since been carried on there, and a complete new set of specimens, diagrams, etc., is gradually being obtained.

The membership of the class is, of course, principally made up from Boston and the towns immediately surrounding, but a few come from places as far distant as towns in Connecticut and Rhode Island, from Bridgewater, Scituate, Framingham, Fitchburg, Lowell, Lawrence, and Beverly.

One member of the class has made an exhaustive study of the granites of eastern Massachusetts, and others are teaching geology in secondary schools outside of Boston.

An important and influential outcome of the first lessons of Mr. Barton was the formation, in the fall of 1888, of the Barton Chapter of the Agassiz Association, by seven ladies who had been fellow-students in mineralogy. Later, men and other ladies who had attended Mr. Barton's field lessons were invited to join. For ten years this club has flourished, and held weekly evening meetings for nine months of the year, at which the members have done much systematic work in the study of geology, mineralogy, chemistry, botany, entomology, and zoölogy. At some of the sessions the individual members have taken their share of the work by the preparing of exhaustive papers which have been read to and discussed by the class, and sometimes a series of lessons has been given by specialists in the several departments. Many of the first scientists of Boston have aided this association by the giving of lectures and advice regarding courses of lessons and opportunities for study, while the club has in return been a great benefactor to many who sought its instruction and the association of those with like tastes. In arranging regular Saturday outings for the study of field geology and botany, this club was the pioneer in this vicinity of the kind of study which happily now seems to be fast becoming popular. A number of persons who were members of this association in their younger years are now holding positions in the United States Geological Survey or other departments of the Government, or in the capacity of curator or instructor are connected with large museums, colleges, or schools in different parts of the country, thereby having opportunities to continue their favorite lines of work, to spread a knowledge of the things about them, and to induce in others tastes such as were fostered in them while connected with the Barton Chapter of the Agassiz Association.

Since closing the four-years' course in botany Dr. Greenleaf has repeated the lessons on vegetable morphology and physiology and those on systematic botany. Finding the class not so well prepared as in former years, instead of continuing the third course of the series, he has given a set of fifteen lessons on the elementary structure and function of flowering plants, as he believed that course to be a necessary foundation for further botanical study.

Another feature of The Teachers' School of Science should not remain unnoticed. It consists of effective work in zoölogy and geology by Mr. A. W. Grabau, the official guide in the museum and a graduate student of geology. A course of lessons on The Shore Animals of New England was begun by him in April, 1897. Directly connected with these field lessons was held a class in laboratory work, which was attended by about twenty persons.

The next year Mr. Grabau endeavored to give his audience a comprehensive view of the action of cold and heat, of winds and waves, rain and rivers, and of the chemical effect of the atmosphere in the production of the natural features of the earth's surface, by giving eight lectures on The Surface of the Earth, its Rocks, Soils, and Scenery. Special attention was given to the scenery of New England, and this awakened an interest in local scenery, which interest led to Mr. Grabau giving several lectures in surrounding towns, under local auspices. One of these lectures called the attention of the people of Arlington, Massachusetts, to the fact that they had in their midst a valuable geological monument, and led them to start a movement for the preservation of a terminal bowlder moraine on Arlington Heights, which is the only good accessible example of such moraine near Boston.

Under the same instruction ten lessons were given on the use of the microscope and the preparation of specimens of hydroids.

The work begun at the winter lectures was continued during the spring by excursions to the seashore. The beaches of Revere, Swampscott, Marblehead; the cliffs and tide pools of Nahant, Marblehead Neck, and Nantasket, and the mud flats and piles of Beverly, were explored. One excursion was made to the outer shore of Cape Cod and Buzzards Bay. The party spent four days on this excursion.

During the early part of the summer an outing was made to Bayville, Maine, where a laboratory was furnished, with microscopes and other accessories, and fourteen persons (mostly teachers) devoted ten days to the study of marine fauna, special attention being given to hydroids. Some geology was studied during this excursion, and a small island mapped. Those who attended this expedition were delighted with an experience new to most of them, as many of them had not before studied zoölogy and knew not what a field could be opened by the study of natural history. One of the party afterward remarked, "I feel as if I had been born into a new world, so different are these things in their homes from their representations in books."

In the autumn and following spring field lessons were given on marine zoölogy, the object being to study animals in their natural habitats. Another excursion was made to Woods Hole, Buzzards Bay, and a summer laboratory established for ten days at Goldsborough, Maine, where work similar to that done the previous summer was here carried out. Among the field lessons of the spring of 1899 was an excursion of four days' duration to Cuttyhunk, one of the Elizabeth Islands, where there was an opportunity to study a marine fauna southern in character and different from that found on the Maine coast. On the afternoon of Agassiz's birthday a sail was taken to another of this group of islands--Penikese, the site of the famous summer school. In the evening the class of seventeen persons listened to the reading of selections from the life of Agassiz, poems regarding him, and magazine articles describing events connected with the great meeting in the summer of 1873. The next day an excursion was made to Gay Head, Martha's Vineyard, where the afternoon was spent in studying the wonderfully colored clay cliffs and in searching for fossils. As an outcome of Mr. Grabau's field lessons the Hale House Natural History Club was formed. This club consists of teachers and other persons who have banded together for the study of natural history. Meetings are held twice a month, and similar classes have been formed for children of the neighborhood.

The Teachers' School of Science has been of great assistance to the Boston Normal School by furnishing certain of its pupils with instruction in geology and zoölogy.

In 1893 The Teachers' School of Science took part in the exhibition of elementary science teaching made by certain teachers of the schools of the eastern part of Massachusetts. The school was enabled to take part in this public exhibit through the generosity of Mr. T. A. Watson, a pupil in the school, who paid the necessary expenses.

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A collection of articles obtained by the Baron de Baye in a scientific expedition last year to Siberia and the Russian Caucasus contains specimens from very ancient times down. Among them are mammoth bones and chipped flints, like those of the Mousterian period in France, from the Yenisei; arrowheads, like the European and American, from the same region; bronze weapons from the Caucasus; iron arrowheads like those of the Congo; skulls, weapons and ornaments, necklaces of hard, polished, pierced stones, from the Kurgans of the steppes, dating from antiquity down to the beginning of the middle ages; Caucasian jewels, and ceramic ware ancient and modern. A very curious object is one of the statues, called Kamenaia Baba, of a kind supposed to have been set up by the Scythians and always held in veneration, of which the present specimen is the only one yet allowed to go out of Russia.

INFLUENCE OF THE WEATHER UPON CRIME.

BY EDWIN G. DEXTER.

The relation between general climatic conditions and the prevalence of suicide has been somewhat exhaustively studied by students of criminology, the result being a considerable accumulation of data and the formulation of a number of more or less tenable theories. From these studies we may safely conclude that the homicidal tendency, as shown by self-destruction (suicide) and the destruction of others (murder), is stronger in the temperate climatic zones than in the torrid or frigid, and that in the late spring and early summer months more of these offenses have been recorded than for any other period of the year. To these few facts the seeming effects of cosmical forces upon such tendencies has apparently been limited.

In fact, it was the oft-repeated statement that nothing was known of the exact relations of the more definite meteorological conditions with the prevalence of suicide--a statement to be found in most treatises upon the subject--that has given rise to this paper. Realizing that the science of climatology must include, and in fact be based upon, a study of the meteorological conditions prevalent, and that the study of these definite conditions for the exact times when suicides or murders occurred might throw some light upon the question, this problem was undertaken.

In the preparation of the accompanying charts, from the study of which the conclusions herein stated were deduced, the record of crime for Denver, Colorado, for the fourteen years ending with June, 1897, was made use of. Superintendent Howe, chief of the city detective service, has kept such a record with the greatest care, and we wish here to acknowledge the many courtesies of his office.

No attempt has been made in this paper to compare the conditions for Denver, either meteorological or social--and each is somewhat unique--with such conditions elsewhere. In fact, such a comparative study is at present impossible since data are wanting.

In the actual preparation of the charts each murder, suicide, or attempt at suicide--which, for our purpose, is equally important--was set down chronologically in the left-hand columns of large sheets of paper ruled for the purpose. These sheets were then taken to the office of the United States Weather Bureau, F. H. Brandenburg, director, where were recorded in the proper columns the maximum and minimum barometer readings, maximum and minimum temperature, maximum and minimum humidity, maximum velocity of the wind, precipitation, and character of the day for each day during the fourteen years on which a crime of either class occurred. When several took place upon the same day the fact was taken into consideration. From the sheets thus filled out, the curves on the accompanying charts were plotted by computing the per cent of crimes of each class committed under the definite meteorological condition indicated.

The curves marked "normal" were constructed by tabulating in a similar manner the conditions for every day in a sufficient number of days to secure a fair average. Five years were so tabulated for Figs. 2, 3, 4, and 5, and the records for nineteen years used in Figs. 1 and 6.

The whole number of suicides recorded is two hundred and sixty; murders, one hundred and eighty. It may be noted that this number of suicides, for a city averaging hardly one hundred thousand inhabitants for the fourteen years, is largely in excess of the rate recorded for American cities, but it must be remembered that some of these were unsuccessful attempts, and also that the social conditions of Denver tend to swell the number--containing, as it does, so many disappointed in the last struggle for health.