Popular Science Monthly/Volume 55/September 1899/Teachers' School of Science II

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1402259Popular Science Monthly Volume 55 September 1899 — Teachers' School of Science II1899Frances Zirngiebel




PARALLEL in time with the course in historical geology or paleontology was that in botany, under the leadership of Dr. Robert W. Greenleaf, a Boston physician, who in his student days had assisted Dr. Goodale and was at the time of giving these lessons Professor of Botany and Materia Medica at the Massachusetts College of Pharmacy. A growing interest in the study of botany in the schools, and Dr. Greenleaf's exceptional ability as a teacher, made the attendance at this class very large. After an hour's lecture the instructor and two assistants directed the observation of the specimens by the students, who were required to make sketches of the objects studied. The first set of lessons was similar to that given in the school by Dr. Goodale several years before, and was of a preparatory nature, including morphological, structural, and physiological botany.

The introductory lesson dealt with the relation of botany to its various subdivisions and to other studies. The meaning of morphology was illustrated by comparing the four plant Robert W. Greenleaf. members—root, stem, leaf, and plant hair—with the different plant organs, and a practical exercise, with specimens whose parts were sketched and labeled, was given to show that the position and mode of development of a part determine its rank as a member or structural division, while its function may give it quite a different rank as an organ.

A preliminary view of vegetable histology, considering the shape, wall, markings in the wall, and contents of cells, was next given. This was followed by lessons on vegetable physiology, in which the absorption of liquids and gases for the making of food, assimilation, transfer and storage of food, the growth of cells and tissues, the excretion of waste products, special kinds of work, as climbing, catching of insects, etc., reproduction, and the process of metabolism as illustrated in cells, were treated of first in a general way and then elaborated upon in the succeeding lessons. Much time was devoted to the anatomy, histology, and germination of seeds and to the structure and function of root, stem, and leaf. The morphology of fruits and their anatomical classification (profusely illustrated from the fruits of the market and neighboring fields), with a discussion of the contrivances for dissemination of fruits and seeds, furnished subject-matter for both a profitable and interesting lesson. The last lessons of this set were devoted to the study of the flower and its parts, particularly stamens and pistils, and ended with an explanation of the processes of pollination and fertilization. The work of making vertical and horizontal plans of the flower served as an introduction for the second year's course on Systematic Botany, wherein the relations between the common families of flowering plants were shown. This course was illustrated by numerous hothouse flowers and also by dried specimens, of which one hundred kinds were given to each teacher. This course was given to teachers, many of whom could by means of a key analyze any common flower, but who knew nothing of the principles of plant relationship. The theories of special creation and of evolution were explained, and the theory of descent with variation was taken as a hypothesis.

Starting with this theory of evolution as a basis, the structure of certain families was studied and they were taken as types with which other related families were compared. After a classification of all known flowering plants into gymnosperms and angiosperms, and subdividing the latter into monocotyledons and dicotyledons, the lily family was considered as typical of monocotyledons. It and its related families afforded a simple means of demonstrating the problems under consideration. Members of this family were found to be characterized by having an endogenous stem, usually parallel veined leaves, six-parted perianth free from a three-celled superior ovary, and six stamens. The allied families were shown to agree with the type in the internal or fundamental characters, such as the number of carpels and cells of the ovary, but were found to differ in the more external or environmental characters, such as the arrangement of the parts of the perianth.

After studying the relations between the various groups of endogens, the trees and weeds of the apetalous division of exogens were next considered, and through Ranunculaceæ connected with polypetalous dicotyledons. These latter were classified according to whether the parts of the flower were hypogenous, perigynous, or epigynous. These terms signify, respectively, under the pistil, around the pistil, and on the pistil. In this group the rose family presented several modifications of the pistil, according to which it was divided into tribes.

When the group of Gamopetalæ was studied, Solanaceæ, the nightshade family, with its regular flower, and Labiatæ, or mint family, with irregular flower, were taken as types with superior ovaries. Various modifications from these types were found in several families.

Ericaceæ, the heath family, presented, in its suborders of Ericineæ, Pyroleæ, and Monotropeæ, which had superior ovaries, and Vacciniæ, which had inferior ovaries, an intermediate order between the preceding superæ and following inferæ, of which latter group Campanulaceæ was considered a type.

The relations between many families were traced, and the Compositæ were lastly considered, this family showing the greatest differentiation with its coalescence of circles, adnation of different circles, reduction in parts, and number of individuals brought together. The greatest deviation from a simple flower and a complexity of structure were here presented. Through the co-operation of parts these flowers were of high physiological efficiency.

Throughout the course, families of medicinal or other economic value, or such as presented evidences of adaptation for cross-fertilization, dissemination of seed, life in desert regions, or contained examples of parasiticism or many poisonous genera, were incidentally considered.

Carefully made illustrated notebooks, collections of dried specimens, and other evidences of interest in the course were shown by the teachers, who gained great facility in placing an unknown flower in its proper family without the use of a key or botany.

The next set of lessons in the botanical series consisted of the usual number (fifteen) on cryptogamic botany. This was perhaps the course which was the most difficult of presentation; but, not-withstanding, much dried and fresh material, representing chiefly the higher cryptogams, was distributed among the pupils and examined by them.

The fourth and last year of the series was spent on paleobotany. This was a somewhat novel and valuable course, which was particularly appreciated by those who had studied geology and paleontology in other classes of the school. A large amount of laboratory material was provided from the museum. The duplicate fossil specimens of the society were used by the class, and ninety determined species were figured by many members. Since the close of these lessons persons who have shown throughout the four years a satisfactory knowledge of botany and have passed the examinations, in the most exhaustive course ever given in the subject for teachers, have received certificates stating their qualifications.

In the spring of 1887, owing to a suggestion made by Professor W. O. Crosby and to assistance furnished by him, a private course of instruction was arranged by Prof. G. H. Barton, of the Institute of Technology, for a series of lessons in field geology. Twenty-one persons, nearly all of whom had attended Professor Crosby's course in The Teachers' School of Science, took these lessons with great enthusiasm. The series of lessons was continued in the autumn, with the addition of twelve new members to the class. From this beginning has grown the systematic course of field instruction in geology now carried on as one of the regular courses. As at present conducted, it consists of a series of lessons in the autumn and spring of each year, so arranged as to give detailed instruction in methods of observation covering a range through all portions of the subject, embracing mineralogy, lithology, structural geology, historical geology, and physiography.

The method pursued is as follows: The class is taken to a typical place for illustrating the subject in hand. The area to be studied is pointed out, and then for a half hour or so the class is asked to make observations unassisted by the instructor and George H. Barton. with as little communication among themselves as possible. Then they are called together and questions are asked to draw out the results of their observations, free discussion being invited at this time, and questions from the class answered by the instructor. Then the instructor explains the phenomena studied, and finally gives a general lecture upon the particular subject involved. Notes, taken in the field, are carried home and rewritten and then handed in at the next lesson, to be corrected and returned later. A printed synopsis is furnished each member of the class at every lesson, for which payment is made sufficient to cover the cost of the printing. Each member is also required to be provided with a hammer, chisel, and compass.

The course of instruction begins with a discussion of the general principles of erosion, and one lesson each is given at places illustrating an excess of chemical and mechanical action. At Medford a very broad dike of coarsely crystalline diabase, penetrated by numerous cracks, furnishes an exceptionally good opportunity for the observation of rapid chemical decomposition, an almost complete gradual transition being shown from the fresh unaltered rock through all degrees of decomposition to the formation of soil. The cause of the decomposition is explained, with the resulting products, and the history of the latter is traced till they form parts or the whole of a new rock. A drumlin is seen, at Great Head, Winthrop, being undermined and worn away by the waves. By comparison with other drumlins in the neighborhood, the original form of Great Head can be easily restored mentally and the effect of waves and currents upon a coast can be readily appreciated. In an excursion to North Adams and rides over the Hoosac Mountains and to the summit of Greylock, rivers are seen in their various stages of action, the cutting backward by the cascade action, the cutting downward of torrent action, and the more quiet transportation and final deposition of the streams passing through the lower levels and approaching the sea. From the sides of Hoosac and Greylock the surface of the Massachusetts plateau is seen, with its dissection by the Berkshire and Deerfield Valleys, illustrating the broad effects of erosion over the surface of the continent.

Passing next to a discussion of the disposition of the material that is derived by erosion from the land, a lecture upon the sorting action of water is given, and the resultant beds of gravel, sand, and clay are studied in a section cut by the Fitchburg Railroad through the sand plateau at Lake Walden, in Concord.

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 Fitehburg, 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

Teachers' School of Science. Field Class in Geology. Prof. George H. Barton, Instructor.

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

Field Class in Zoölogy. Looking for Shore Life among the Bowlders at Woods Hole.

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 elfect 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.

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.