Johns: Maps and Records. 



261 



this and other iocal work should be as complete and accurate as 

 possible. 



It is with the view of not only indicating- a method by which 

 greater accuracy mig'ht be obtained, but also by which the local 

 observer might be compelled to achieve a certain minimum of 

 accuracy at least, that the writer now suggests a method 

 of using maps and recording observations which seem to 

 possess several advantages. It is simple, easy to apply, and 

 what is, perhaps, of still more importance, it renders errors 

 more difficult. It also makes easier the correlation of the 

 results obtained by workers in the different branches of natural 

 science. 



The six-inch ordnance survey map has been taken as the 

 basis of the method. This is the scale which will be found 

 most useful, though the method suggested might, with modi- 



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fications, be used for other scale maps. This map, which 

 measures eighteen inches in length and twelve inches in breadth, 

 is divided by eight vertical lines and five horizontal lines into 

 squares measuring two inches on the side. These in practice 

 should be ruled thickly in red ink, and will each enclose an area 

 measuring one-third of a mile each way. Thin red lines are 

 ruled parallel to and between the thick lines, but much thinner. 

 These inside squares will be one square inch, and enclose 



1905 September i. 



