An Introduction to Nature-study

by E. Stenhouse

Generally speaking, collecting is of very doubtful value, except to experts. Insects and common plants may, however, be collected without scruple by the beginner, though it is worth remembering that the most perfect specimens of butterflies and moths are those reared in captivity from the eggs, larvae, or pupae.

The student is strongly recommended to make a sketch map of some small area to which he has easy access, and to record upon this the positions of features of special interest. Such a map may, in the first instance, be copied on an enlarged scale from an ordnance map of the neighbourhood, which may be obtained at the local free library. It will be advisable to duplicate the drawing by means of one of the many appliances for such work, and to keep one copy each for trees, flowering plants, birds’ nests, etc.—the position of each object, or of a well-defined group, being carefully marked by a small number ([Fig. 237]), and the reference, with the date, being filled in on the margin. The varying character of the ground—sandy, marshy, clayey, etc.—should be indicated by diagrammatic shading or colouring. By following this method the student will more clearly realise that different plants are dependent upon different conditions of soil, drainage, etc.; and that, e.g., plants at home on a bleak moor, in a hedge, in marshy land or in water respectively, are characteristically modified so that they can make the best of their special conditions of life. In this manner he will, almost unconsciously, gain wider views of the relationships which exist between the facts learned from his more detailed observations. It would be a distinct gain to biological science if field clubs also would adopt some such plan, each member undertaking to fill in upon his map information of the animal and plant life of the area allotted to him. The co-operation of various clubs, and the systematic arrangement of information thus obtained, would result in a store of knowledge of the highest value.

Many animals are so shy that they can only be approached with difficulty. In such cases it is especially necessary for the observer to move quietly and silently, and, when a favourable position is reached, to remain as motionless as possible, preferably with his back to the sun. If a field-glass can be obtained it will be of great assistance, but some practice will probably be required before it can be used easily.

It is well to start each ramble with some definite object of study in view—either trees, grasses, flowers, fruits, birds, caterpillars, or pond life, for example, and to be provided with pill-boxes, bottles, etc., according to circumstances. A notebook, pencil, pocket knife, and hand lens should, however, always be carried, and observations should be recorded on the spot.

Pond life.—Practically the only method of gaining a real knowledge of aquatic organisms is by the help of the aquarium. Specimens may be obtained by means of a net, or of a small wide-mouthed bottle tied to a stick. A pickle bottle is convenient for carrying home the material collected. The conditions of a natural pond should be imitated as closely as possible in the aquarium. At first, some little difficulty will probably be found in obtaining the necessary balance between the animals and plants of the aquarium. When this has been reached, it will only rarely be necessary to change the water, provided that dead or sickly specimens are promptly removed.

THE SCHOOL JOURNEY.

In the organisation of school journeys so much depends upon local conditions of various kinds, so much must of necessity be left to the initiative of the teacher, that it is manifestly impossible here to do more than enunciate certain general principles. In the first place, it should be borne in mind constantly that the primary object of the school journey is the cultivation of habits of thoughtful observation; and that the chief danger to be guarded against is that out-of-focus condition into which the mind, like the eye, inevitably falls when it is concerned with too many things at once. To obviate this danger the teacher should go over the route in advance, noting carefully the features, physical and otherwise, which afford material for observation and investigation by the class. The order in which these features may be best studied should be decided upon, and a scheme of several visits, each to be concerned with one special subject of study, can then be drawn up. Such a preliminary survey should suggest a plan by which every member of the class may be allotted a definite task—to find something or do something, or to solve some problem on the spot.

These principles may be best illustrated by a special example, but it will be obvious that the same ideas, with modifications in detail, may be applied in any district. The sketch-map ([Fig. 237]) illustrates a walk through Healey Dell, near Rochdale, Lancashire. The rocks which are exposed at various places along the route belong to the Carboniferous formation, and are composed of shale, coal, or millstone grit.

The object of the first journey will be in most cases to familiarise the class with the “lie of the land” and the most obvious features of the scenery. As a preparation, lessons should be given on the points of the compass and the various methods of finding the direction of the north. The simplest of these is by the use of the compass: it being remembered that the needle points about 16° to the west of true north. A second method depends on the fact that at noon the sun is in the south and that therefore (because the hour hand of a watch makes two revolutions in the twenty-four hours) the north and south line approximately bisects the angle between twelve and the hour hand, if the latter is pointed to the sun when the watch is horizontal. Incidentally, the method of finding the pole-star might be also explained to the class. Further, each pupil should be encouraged to find out how many steps he takes, on the average, in pacing a given measured distance. If the general direction of the walk is north and south, as in the example, it will be found best to begin the first journey at the south end (in this case from Shawclough Station), since to most children it is easier to conceive of a journey northward than in any other specified direction. Throughout the ramble constant reference should be made to the direction of the route and the relative positions of well-marked features of the landscape. The distances between certain points should be estimated, and, whenever possible, measured (by pacing), and notes made by the class. For example, from Shawclough to Ending the distances and directions are roughly: ¼-mile W.N.W., ⅓-mile N.N.W., ¼-mile E.N.E. In the first journey also the class should be made to notice where the ground slopes most and where least (the direction and angle of slope should be estimated in a few cases), and the names of neighbouring woods, farms, etc., should be learnt. The direction of flow of the river and the various bends in its course should also be noted, and reference made to the route by which, after joining those of other rivers, its waters ultimately reach the sea. Afterwards, the pupils should write an account of the journey and, in the higher classes, should be encouraged to draw a sketch-map, however crude, from memory.