460 REPORTS ON THE STATE OF SCIENCE, ETC. 



those taken before. After eacli pupil lias obtained the results of her own 

 experiments the results obtained by all the members of the class can be 

 compiled, and then compared with the results of experiments in former 

 years. In this way reference has been made by girls at James Allen's 

 School, Dulwich, to hundreds of experiments on the formation of starch 

 by green leaves before any generalisation has been made in the matter. 

 Pupils of post-matriculation stage can verify the results obtained by 

 treating the whole leaf with iodine by treating sections of leaves. 



Other experiments which afiord training in scientific method are those 

 of pollination. The function of pollen need not be told. It is quite 

 simple for pupils to make their own experiments, to ascertain a number 

 of facts for themselves, to compare results and to draw their own con- 

 clusions. But, in these experiments, as in others, care must be taken to 

 have control experiments. In the James Allen's Girls' School, Dulwich, 

 where less than one hour a week for one class only in the summer term of 

 each year was allotted to experiments in pollination, successive classes 

 recorded their results, and more than two thousand results showing the 

 function of pollen are available for reference. Also the results of more 

 than five thousand experiments, showing in which flowers self-pollination 

 can take place, have been put on record, in some cases the information 

 not being available in any book. 



Numbers of experiments can also be made on the influence of 

 gravity and the influence of light on the direction of growth of roots and 

 stems. 



Classification of plants may be taken in a scientific way. If carefully 

 selected plants are taken in the early stages of plant study, pupils later on 

 may be able to compare the leaves and the structure of the flowers of many 

 plants, group together those plants possessing the same characteristics, 

 and arrive at a system of classification from the previous observation of 

 facts. 



For pupils of yos<-matriculation stage experiments to investigate 

 Mendel's Laws of Heredity — laws which were first discovered by Mendel's 

 work on plants in an ordinary garden — can be of great value and of 

 absorbing interest. Elder pupils may make experiments such as crossing 

 pea plants having yellow cotyledons with those having green cotyledons, 

 and other simple experiments. 



In making the experiments quoted above, and in many others, pupils 

 studying biology can be trained in observing facts, in comparing the results 

 of their own observations with those obtained by others, in drawing con- 

 clusions from a great number of facts and in verifying those conclusions. 

 By means of experiments they can make discoveries for themselves, a 

 source of pleasure to many, though all cannot say with Boyle ' In my 

 laboratory I find that water of Lethe which causes that I forget everything 

 but the joy of making experiment.' 



But it is well to emphasise the necessity of rigorous examination of the 

 conditions of the experiment and the value of control experiments, and 

 in all cases it is essential that any results, not in agreement with the 

 greater number, should not be slurred over, but carefully considered, 

 suggested explanations of the discrepancies being obtained from members 

 of the class and discussed. 



