May 17, 1895.] 



SCIENCE. 



547' 



has rounded oft' many a trnly angular con- 

 tour line into an inexpressive curve. 



The objection that is sometimes made 

 against tliis view of a topographer's educa- 

 tion and work is that, if he tries to sketch 

 what he thinks he understands, he will 

 sometimes sketch what is not really before 

 him. There may be a certain amount of 

 truth in this, but there are sufficient an- 

 swers to it. A topographer who is too far 

 guided bj^ his imagination has been badly 

 taught, or else he is of a mental ([ualitj- that 

 will prevent his ever becoming a good topog- 

 rapher, quite apart fi-om whatever education 

 he has had. The well taught topographer 

 will make no larger share of mistakes on 

 account of being well informed on his sub- 

 ject than will the well taught systematic 

 botanist or zoologist. The few mistakes of 

 interpretation that the well taught topog- 

 rapher may make will, I believe, be far out- 

 weighed bj' excellence of the other part of 

 his work. 



It is perhaps because I have a higher 

 idea of a topographer's work than ordina- 

 rily obtains that I should like to see him 

 generally better educated for it. To my 

 mind, a map is so far from being a copy of 

 nature that I should prefer to call it a 

 graphic description of nature, and in the 

 making of this graphic description the 

 topographer should study his subject and his 

 graphic signs with the same care that a 

 writer should study his thoughts and the 

 words he employs to represent them. In- 

 struments, to which some topographers 

 seem to give their first attention, ought to 

 have about the same place in their real 

 work that a typewriting machine has in 

 the work of a literary man. 



The chief subject of the topographer's 

 study should be the form of the land before 

 him ; and until this is recognized in en- 

 gineering schools and enforced by a careful 

 course of preparatory physiographical study, 

 I believe we shall not have the best majis 



that can be made. Even further, it is as 

 impossible to make a good topographer by 

 merely teaching him about plane tables and 

 stadia and logaritlmis as it is to make an 

 essaj'ist by teaching him about writing and 

 spelling. It seems to me, in fine, that Pro- 

 fessor Merriman's interest in the mathe- 

 matical aspects of the art of topography 

 leads him to place too low a value on the 

 importance of studying the chief subject of 

 the topographer's attention, the forms of the 

 land. "W. M. Davis. 



Cambridge, Mass., April 30, 1895. 



THE HELMHOLTZ MEM0RI.\L. 



A FEW months ago Hermann von Helm- 

 holtz died, one of the greatest scientific 

 geniuses of all time, whose name will not be 

 forgotten as long as men care for the knowl- 

 edge of Xature. His invention of the oph- 

 thalmoscope made the success of tlie modern 

 oculist possible : his papers on the conserva- 

 tion of energy gave the strongest impulse to 

 modern physics ; his books on seeing and 

 hearing became the basis of modern psy- 

 chology. 



It seems a matter of course that the pres- 

 ent generation should express its gratitude 

 in a lasting monument. Xot only his friends 

 and pupils all over the world, but men of 

 science and physicians everywhere have 

 supported this idea, and so last month an 

 International Committee was formed to col- 

 lect money for the erection of a gi'eat Helm- 

 holtz monument in Berlin, where for the 

 past tM^enty-live years he lived and worked. 

 The plan has nothing to do with local pa- 

 triotism ; America, France, England, Italy 

 and Russia are represented on the Commit- 

 tee ; not a decoration of the city of Berlin 

 is in question, but a universal expression of 

 devotion to the spirit of natural science. 



Xo doubt America will take a veiy high 

 place in the list of givers. There has been 

 seldom such an opportunity to show that 

 the United States does not stand behind any 



