PRECIPITATION 25 



such accuracy is desirable is no part of his mental equipment. 

 In our Nature Study course, then, if we measure we measure because 

 we want to get at certain facts only obtainable in that way. 

 In the first instance at least the teacher is wise to accept all 

 results, even slovenly ones. As we go on, and as we proceed to 

 use our results, we find that if they are inaccurate we become 

 involved in all sorts of difficulties, and thus slowly, and in the 

 natural way, the need for care and accuracy dawns. But let 

 us strive above all things to follow the natural order, not to take 

 the means for the end, to measure because we want to know, 

 and not for the sake of measuring, not for an abstract purpose 

 beyond the child's reach. 



The measurements involved in observing rainfall are simple, 

 and can be carried out without great strain. As we do not propose 

 to send our results to the rainfall organisation, a standard-pattern 

 gauge is not necessary a jam pot, a funnel from the cook, a 

 measuring glass from some one who goes in for photography will do 

 to start with. If, as is increasingly the case in schools, the building 

 is furnished with meteorological instruments on which regular 

 readings are taken, it will be useful to compare our more or less 

 haphazard readings with the more formal ones taken by the higher 

 classes, to find out to what extent the difference, if any, is due to 

 carelessness, and to what extent to defects in the instruments. If 

 the school has no meteorological station the neighbourhood will 

 probably contain one, or at least some interested amateur, who will 

 not object to give his results for comparison. If both conditions 

 fail, the daily newspaper will almost certainly give meteorological 

 notes. These facts are important, because one wants to convey 

 to the members of the class the idea that what they are doing 

 many other persons are also doing, one wants to be careful to 

 remove as far as possible the air of unreality from the Nature 

 Study course an air it is only too apt to have. 



One would naturally begin rainfall observations at a time of 

 year when the rainfall is heavy. As a general rule in Great Britain, 

 October and November are months of high precipitation, while the 

 spring months, notably April and May, are months of low rainfall. 

 The autumn is thus a good time to begin. If possible, a spell of 

 wet weather should be chosen as the date of beginning. At such 



