DIFFICULTIES IN FIELD TEACHING. 323 



These hindrances are protean in form, but they are most commonly to 

 be found in an inability to think in three dimensions any better than we 

 can in four, and an incapacity to continue any work when alone. As to 

 the first of these defects there seems to be no resource except to revive 

 the natural dimensional sense which primitive peoples have. If the 

 student has had sound training in solid geometry he may the more 

 quickly recover the capacity to form the special conceptions which are 

 required of the geologist; but the natural solid is quite another thing 

 from the ideal, and while the theoretical view^ of them is the same the 

 practical experience is very different. Some youths never learn to deal 

 with the earth problems from the solid point of view. They are there- 

 fore cut off from the better uses of the field ; yet even with this signal 

 disadvantage they may do good work in certain parts of the science. 

 One of the most distinguished of our American geologists, now dead, was, 

 perhaps on account of the fact that he saw from but one eye, quite with- 

 out the sense of the relations of the solid ; yet, while in the field- w^ork his 

 success as measured by his talent was limited, his contributions in other 

 departments were great and of enduring value. Nevertheless, though the 

 people who abide in two dimensional spaces may possess abilities of a 

 high order, they should be kept out of the science which more than any 

 other calls for the ability to frame three dimensional conceptions. 



An inability to work alone in the field is a rather common and in my 

 experience an incurable defect in certain students who would otherwise 

 be fitted for geology. Those who are thus afflicted appear to lose their 

 motive of inquiry when they are parted from their fellow-men. Their 

 malady is to be regarded as one of the many defects of body and mind 

 which are due to over-housing — to that absolute separation from the peace 

 of the wilderness which characterizes our city life. 



As soon as possible the field student should be brought to the point 

 where he is required to make his own maps, at first as sketches, and then 

 in the more formal way by pacing, with some methodical control, such 

 as by a simple triangulation. One piece of such map-work where the 

 delineation of the surface in general ground plan and contour, as well as 

 the geological coloring, is from his own labor will often be sufficient to 

 affirm the working power of the man. In the ideal of the system such 

 instruction should come to every student who undertakes the study of 

 geology, but in practice it will probably be gained by very few. In the 

 department of Harvard University which is devoted to the science about 

 300 men each year enter on the elementary work. Of these not more 

 than the eighth part continues the study to the point where they may 

 begin to do work which may be regarded as independent ; yet fewer essay 

 the training which looks forward to a professional career. As this de- 



XXXVl— BuLi,, Geol, Soc. Am., Vol. 7, 1895. 



