394 HOW TO SEE WITH THE MICROSCOPE. 



well as my Dunkirk lecture. Allow me to assure you, my dear 

 professor, that although we have been pulling at opposite end* 

 of the rope for some months, the generosity I have experienced 

 at your hands has been vastly in advance of what I could have- 

 returned, and has placed me in position to receive any criticism 

 that you might offer with the best possible grace. 



I now propose to jerk my end of the rope in a manner that 

 will make things lively with you I The fact is, when I get 

 after you with a ** sharp stick " you become unusually brilliant 

 with the jerk responsive I I like it. 



I admit that you are one " who demands accuracy of expres- 

 sion in every branch of science" "that the scientist has no 

 right to say what he does not mean, and he has no right to pre- 

 sume that his readers will understand him if he uses incorrect 

 language." I therefore have placed the above little monograph 

 on elementary astronomy at your service, and in timely season, 

 fearing otherwise you might be led astray by my use of the- 

 word u sundown "you will see the point. It's true that Joshua 

 of old commanded the sun and moon to stand still, and the 

 story is found in a book generally admitted to be a classic, but 

 no matter. 



Now, professor, I fear that you do not practice what you 

 preach ; for I read (page 92), " if this question were put to a 

 thorough physicist * * * knowing nothing about 

 balsam or fluid mounts, etc." Isn't there an " impossibility "' 

 here V A thorough physicist knowing nothing, etc. There's a 

 screw loose somewhere. 



liight on your next line is another jumble. Here is a want of 

 accuracy or what not which is it ? You say " Must the scien- 

 tist .be led by the nose," etc. If this expression is accurate, 1 

 want you to tell me just how this kind of a thing is accom- 

 plished ; give me the p-r-a-c-t-i-c-a-l details, just as it would be 

 done in the flesh, including the " adopt " and the " teach " 

 before an audience, too, without " apology" and the why of 

 it. " It's the right and duty of every man of science to ask this 

 little question whenever it occurs to him." " The scientist has no 

 nqlit to say what he does not mean." Let us have the facts. 



Part Second. 180, plus 180, 180 + 45. It is true, my dear 



