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DISCUSSION AND CORRESPONDENCE LABORATORY INSTRUCTION IN CHEMISTRY;
ITS AIMS AND ITS LIMITATIONS It is now well over half a century since the laboratory has been regarded as a necessary feature in the study of science elementary as well as advanced. Before that laboratory methods of instruction were rarely practised and were available only for the exceptionally fortunate, or probably exceptionally able, student who had hrst demonstrated in a purely intellectual way his aptitude for science.
The greatness of the achievement of the brilliant scientific men before, say the middle of the nineteenth century, with poor facilities for work, and inadequate knowledge upon which to build, certainly furnishes an argument that intellect may be stimulated rather than discouraged by lack of practical facilities,
The question must present itself to every one connected with training students in scientific schools, to what extent expensive laboratory facilities are justified, particularly for the great numbers of elementary students, when compared with the results achieved. No one will argue that direct observation of scientific phenomena in experiments performed with the student's own hands does not increase the student's familiarity with the phenomena. Perhaps we might say that the impression made upon the student's mind by a personally performed experiment is so much more vivid than the impression made by a written statement in a text-book, or even by an experiment performed by the professor on the lecture table, that the phenomenon is remembered with much less intellectual effort. Since however progress is attained only through the expenditure of effort, we may well ask, will the student of science reach as high a plane of intellectual development if the laboratory is used too freely for demonstration purposes.
The writer acknowledges as the immediate stimulus to present these thoughts, the article in SCIENCE of May 30, 1919 (page 506) upon “ The Freas System,” written by Dr. W. L. Estabrooke.
The Freas System is obviously a recognition of the problem of balancing the costs of lab
oratory instruction against the results. It is to be hoped that further details of this system promised by the writer will bring its advantages fully to the knowledge of those who have the administration of the laboratories of our schools and colleges. Certain rather broad aspects of the question are suggested by the first article and it is to be hoped that they will be discussed by the advocate of the Freas System.
The Freas System seems to be a species of modern factory efficiency management applied to laboratory administration. There can be no doubt that all possible efficiency in obtaining, distributing and conserving laboratory supplies and apparatus is to be desired, nor is there any doubt that without careful planning and a capable administrator in charge the efficiency will be low. But how far will the enthusiasm for efficiency in handling supplies tend to reduce the instruction to a lifeless routine. It would almost seem as if in the Freas plan the structure of the laboratory course had been built around the framework of the system of supply distribution. For we are told that at the beginning of a term the student receives supplies exactly sufficient for a whole term's work in a carefully planned kit. Such a kit contains for some of the courses as many as 140 different bottles of materials.
Modern American factory methods are marvelous when measured by the material output, but they do not rank so high when measured in terms of the welfare of the individual worker. Perhaps the solution of the factorylabor problem will recognize that the welfare and happiness of the individual workers is the framework around which the structure of industry must be built. No educator thinks other than that intellectual development is the aim to which educational effort must be directed. The writer does not see how a standardized routine of laboratory experiments can stimulate the intellectual development of a student any more than the intensive drive of production in a textile mill can stimulate the joy of life in the worker standing day after day in the same place over noisy looms.
The primary purpose of the experimental The writer believes that efficiency methods laboratory was to carry out original investiga- which increase the output of material prodtions. It is well not to lose sight of the fact ucts of an industry are not directly applicable that the laboratory of elementary chemistry to the development of intelligence. True, the can appear to the beginning student a place of Freas method may double the number of exoriginal investigation. Indeed it is probably periments which the student will perform in safe to say that the amount of intellectual a laboratory period. But can we measure the stimulus he receives in the laboratory is in development of the student by the number of direct proportion to the extent to which he experiments performed any more than we can takes the attitude of an investigator.
measure the happiness of the mill operative by It is more often the case than not that after the number of yards of fabric which he can a student has performed a routine experiment get through his looms in a day. in a routine manner, he will retain of it so Scientific research is in its nature inefficient vague a recollection that he will be unable to if judged in terms of the formulas of prorelate his observations the next day in the duction experts. Yet research is recognized class room. When however the experiment by large industries as a vital part of their has developed some unexpected feature which organization. perplexes him enough to incite him to try out
The value of laboratory work depends mostly
in variations of the experiment upon his own
on the extent to which the students feel the initiative, he will be found full of information
research spirit-even if in but a very feeble and argument in the class room.
way in elementary laboratories. The acquirElementary experiments may be classified
ing of manipulative skill and the learning of
properties which are better stated in the textinto two kinds: (1) isolated short experiments,
books than they can be observed by the stuand (2) sustained experiments. The short
dent, are for the most part incidental to the experiments may be planned in a beautiful
more important purposes. To encourage this sequence, each building on the results of the
spirit of research, reagents must be available preceding ones in a manner to arouse the ad
on the side shelves for free use within reasonmiration of an instructor. Yet to the stu
able bounds. In fact a well-stocked outfit of dent they seem just isolated experiments and
reagent shelves serves as a chemical museum he is only too likely to receive the impression
and time spent in going to these shelves, inthat the standard of his work is measured by specting the chemicals there, and sometimes the number performed. Even when the stu
in trying out reactions not specified in the dent is above the average of intelligence and directions, is surely not time wasted. Natsees pretty clearly the sequence as planned by urally the student should be expected to work the instructor, he still does not develop very industriously during laboratory time and he much enthusiasm for a thing which has been should perhaps be expected to perform at least all planned out for him.
a certain minimum number of “required” (2) The type of experiment referred to as experiments. But he should not be continsustained is illustrated by the “unknowns” ually driven to realize the highest value of the of qualitative analysis, and by chemical prep- ratio of experiments done to length of labarations. In each of these cases there is a oratory period. He should rather be distinctly definite objective set to work toward, the work encouraged to work thoughtfully and be made is prolonged enough to awake a sustained in to feel that quality is given more recognition terest, and there is a tangible result obtained than mere quantity. when the experiment is finished. Moreover, At all events there must be a compromise in the manipulations require judgment and elementary laboratories handling large classes, develop incidental problems not foreseen in between efficiency of the supply service on the the directions.
one hand, and the scientific inspiration to the
to see if perhaps the issue itself ought not be reconstructed in such a manner as to avoid the necessity of a compromise.
ARTHUR A. BLANCHARD MASSACHUSETTS INSTITUTE OF TECHNOLOGY
individual student on the other hand. It is hard to see how cut and dried laboratory experiments, with all materials measured out in advance ready to be put together, can interest an intelligent student so much as experiments performed on the lecture table.
The writer realizes that many will deem him guilty of heresy even for putting the question: Do we give too much laboratory work in our science courses? If it becomes necessary on account of expense to so standardize the laboratory work that it loses nearly all its stimulus, were it not better to omit laboratory from the program until at least the point is reached where experiments described earlier as of the sustained type apply? .
Some students are at school or college for a general liberal education—not to specialize in science. How shall they be treated if they elect to study the elements of chemistry? Is the expense of even a standardized and denatured laboratory course justified? When chemistry is chosen mainly for the object of intellectual development does not the class room work without the laboratory serve the purpose? Indeed does it not require a higher order of intelligence to visualize a chemical phenomenon from a text-book statement alone, than from a laboratory demonstration ?
The writer has ventured to raise questions in the foregoing some of which have an obvious answer, others of which have been viewed for more than a generation in a uniform dogmatic manner, but ought now to be reopened and reconsidered on their real merits. The Freas System involves these questions, and it constitutes a compromise between two unreconcilable conditions. So far as the evidence presented in the article referred to goes, it seems like the case in which the compromise was effected by one party acceding to all the demands of the other. However, a misconception may have been gained from the first article of the series and the other numbers should be awaited with interest.
Furthermore, if an issue seems capable of adjustment only through an unsatisfactory compromise, is it not the part of wisdom to reexamine the conditions underlying the issue
METEOROLOGY AND THE TRANS-ATLANTIC
FLIGHT WITHIN the past few months many millions of people have had their attention directed, as never before, to the importance of meteorological conditions in connection with the question of trans-Atlantic flight. A popular interest has thus been aroused which has been but partially satisfied by the often contradictory and usually rather meager information supplied by the daily newspapers. Many persons doubtless have a real desire to inform themselves more fully in regard to the weather conditions which are likely to be met with at various altitudes over the North Atlantic Ocean. A recent paper on « Trans-Atlantic Flight from the Meteorologists' Point of View"1 brings together, in compact form, just the sort of information of which the intelligent public is in search. The author, Willis R. Gregg, of the Weather Bureau, was actively concerned as a meteorological expert in connection with the flight of the U. S. Navy planes. The fact that Mr. Gregg's article was in print before the recent transAtlantic flights were accomplished does not in any way detract from its interest or value.
Mr. Gregg's chief conclusions are as follows: Favorable conditions of wind and weather are necessary for the safety of airplanes which attempt the trans-Atlantic flight. In order to obtain the requisite knowledge of the prevailing atmospheric conditions, frequent and widely-distributed observations are necessary. When a favorable day comes, the meteorological expert can indicate the successive directions toward which the airplane should be headed in order to keep to any desired course, and can also calculate the assistance which the winds will furnish. Favorable conditions for an eastward crossing are found at 500–1,000 an
1 Mo. Wea. Rev., Vol. 47, 1919, pp. 65–75.
meters during about one third of the time. war, shows the splendid progeny of the liaison The percentage of favorable days increases de convenance hurriedly arranged between materially at greater altitudes, especially along science and industry. It is to be hoped that the northern route. The percentage of favor- it will lead to a more permanent union. able days for the westward trip “is so small The war is over, and there is more than a as to make trans-Atlantic flight in this di- fear that the soporific effect of the cry “ Busirection impracticable until the cruising radius ness as usual” may again be felt. Business of aircraft is increased to such an extent that will not be as usual. The old British way of they are relatively independent of weather con- being content with large-scale manufacture of ditions."
the “good enough,” of seeking the easy As to the season, there is little choice. The market and the repeat order, is gone for ever. prevailing westerly winds are stronger in win- Even the best is not good enough, for there ter than in summer, but there are more storms is always a better. As Lord Moulton said, in the colder months. The greater prevalence Divine discontent must have its place in our of fog in summer is a disadvantage at that industries. The manufacturer must keep in season which about offsets the greater amount touch with the inventor and the scientific of cloudiness in winter. The fogs of New student. The men of the laboratory must foundland are generally of but slight vertical keep aware of the industrial processes to extent, and as they do not extend far inland which they can so largely contribute. The they ought not to interfere with a landing if seller of British goods must have a better such is attempted some distance from the weapon than blandishment; he must be able coast. The most important thing of all is the to explain why his goods are the best, and to need of a comprehensive campaign to secure stimulate the imagination of his customers by meteorological and aerological observations the assurance of better. Lord Crewe rightly over the North Atlantic.
laid stress on the part of education in the R. DEO. WARD new orientation of our scientific and indus
trial effort. He referred with legitimate pride QUOTATIONS
to the associations of manufacturers and inBRITISH SCIENCE AND INDUSTRY
vestigators that are being organized by the
Council of Scientific and Industrial Research. THE speakers at the opening of the British
But there is still a long way to go. In one Scientific Products Exhibition emphasized
sense, the lean years that lie ahead of us are different aspects of the same truths. When
less favorable to continued effort, although the war came, England was deprived of many
they require it even more urgently. During scientific products which she had been con
the war an imperative stimulus quickened our tent to receive from Germany. English sci
common purpose. Money flowed like water entific men and inventors had long been in
for the experiments of the laboratory and the the forefront of discovery, but English manufacturers had taken little advantage of their
workshop, and the operations of war supplied
the swiftest and surest test of efficiency. We achievements. We had not the industrial processes for making high explosives from
must lose none of the organizing and selfcoal-tar nor the methods of making optical
sacrificing spirit that we gained when our
need seemed greatest.—The London Times. glass for gun-sights. In a thousand ways, great and small, we were unready for the ordeal. The unlimited valor of our fighting
SCIENTIFIC BOOKS men and the unswerving resolution of the The Turtles of New England. By HAROLD people alone carried us over the dead point. L. BABCOCK, M.D. Mem. Boston Soc. NatThe exhibition of British scientific products, ural History, VIIII., No. 3, 4to, pp. 325 to made in Britain, for the first time during the 431, plates 17 to 32, April, 1919.
from time to timSociety of Nate
tory of which this paper is a detail. Larger institutions are often absorbed by distant problems and work of this nature is much needed to keep the study of natural history well balanced.
J. T. NICHOLS AMERICAN MUSEUM OF NATURAL HISTORY
This is the most recent of the series of monographs of small groups of vertebrate animals issued by the Boston Society of Natural History from time to time. The seventeen species of turtles recorded as native to New England are taken up in order and described, size, color, form, distribution, numbers, breeding, food, enemies, economic importance. The plates comprise careful color drawings by R. Decker and J. Henry Blake, of all but the marine leather-back, loggerhead and green turtles, and photographs of these three. The illustrations facilitate the identification of the different turtles, supply the best existing figures of certain comparatively little-known species and, as representative of New England material, will be valuable for reference to faunal herpetologists. There are several pages of bibliography of references cited. Of the seventeen species of turtles treated, four are marine, one littoral, one almost strictly terrestrial, one strictly aquatic, and ten more or less amphibious. Exclusive of the marine species, six are rare or local in New England, the remaining seven being the snapping turtle, musk turtle, painted turtle, diamond-backed terrapin, spotted turtle, wood tortoise and box tortoise.
This publication will be welcomed by the students of the fauna of New England and herpetologists in general, but it should have a much wider circulation. Ability to refer to it will add to the pleasure which every New England child may be expected to find in turtles. The turtle is one of the most striking of nature's phenomena and the correlation of its remarkable structure with its habits has much popular interest. A careful consideration of the life-histories of the different species is a feature of Dr. Babcock's work. From the quotations it is noticeable how many interesting things about turtles have only recently come to light and we are impressed with the probability that others as interesting remain to be found out.
In conclusion, a word should be said of the thorough investigation of the New England fauna by the Boston Society of Natural His
SPECIAL ARTICLES THE FUNGUS PARASITE OF THE PERIODICAL
CICADA The fungus Massospora cicadina, Peck has been extremely prevalent about Washington, D. C., during the recent reappearance of Brood X of Cicada septendecim. It was first collected in the conidial stage of development on May 31, or about ten days after the first emergence of the insect in this locality. Until June 7, however, it was not abundant, it being possible to collect only a dozen or so infected cicadas in an afternoon, and during this period only the conidial stage of the fungus was found. On June 10, however, following a wet period of a few days, the organism appeared in the resting spore condition and since this date has become increasingly prevalent until, at the present time, from five to nine out of every ten live adult males collected will show the resting spores of the fungus in some stage of development. On the other hand, infected insects showing conidia are rarely found now.
It appears from the observations made thus far that conidia and resting spores of Massospora cicadina are not formed simultaneously in the same insect, and infected individuals bearing only conidia of the fungus present a somewhat different gross appearance from those insects in which resting spores exclusively are produced.
In the conidial stage of development the fungus is usually exposed to view, due to the sloughing off of several of the posterior abdominal segments of the host's body, as a white or pale cream colored more or less coherent mass which is found to arise in the male hosts at least from a cushion-like substratum, the latter forming a more or less complete septum extending across the entire