NEW CONCEPTIONS IN SCIENCE 



black spots that the break in the wall actually 

 occurs. 



These spots are black only by contrast. Seen 

 in a strong light, they present a series of ring-like 

 colorations, and it was this part of the soap-bubble 

 that Newton studied most deeply. These rain- 

 bows are known as Newton's rings. 



Old Sir Isaac was an indefatigably curious man. 

 Reading the Queries that he puzzled over, and then 

 wrote down, makes one think there were few things 

 in this world his wonderful brain did not find time 

 to ponder. Some of the guesses he made, at things 

 beyond the reach of experiment in his day, came so 

 close to the truth that they seem almost like pre- 

 visions. Of course, they were not ; it was simply 

 that he "intended his mind upon things," as he 

 says, more than other folk are wont to do. 



Searching for the extreme limits of continuous 

 or solid matter (as opposed to liquids or gases) , the 

 black spots or rings in a soap-bubble were the thin- 

 nest things Newton could find. So far as accurate 

 measurement goes, they remain so to the present 

 day. These black spots are at most not more 

 than 12 up or 14 /u/n thick. It would take about 

 ten thousand such thicknesses together to equal 

 one sheet of this paper. And there are parts of 

 the black spots, the centre, only half as thick as 

 this that is, only about seven micro-microns 



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