ASTRONOMY. 239 



A theory that gives prevision in so many directions must be almost or alto- 

 gether true. Cauchy's explanation of the uneven refraction of all colors of light 

 was a nearer approach to a complete solution of the myriad changes wrung upon 

 waves by varying conditions but as it is strong evidence in favor of the discrete 

 character of matter of course it is objected to. New facts in the case have arisen 

 for explanation. These show that some of us have overestimated the amount of 

 delay in ether and underestimated it in transparent, dense bodies. What of it? 

 Who pretends to have solved the problem of transparency ? Is it utterly improb- 

 able that the molecules of a piece of glass or of some bisulphide of carbon take 

 part themselves in the undulations going through them ? We know they delay 

 light far more than ether does. 



Give us the finite intervals and attractions in air, glass, and transparent 

 bodies generally and have them conduct light upon their own substance instead 

 of through their pores and the problem is solved. Can Judge Stallo or any other 

 person say that these are not facts in transparency? The Judge says that if 

 sounds of all pitches did not travel in air with equal speed music at a distance 

 could not be heard as such, but would reach our ears as a gamut. Does he not 

 know that with waves of sound as large as we know they are and with molecules 

 of air as small as we know they must be, we would have to hear the music at 

 a practically infinite distance for such a phenomenon to manifest itself? Cauchy 

 has proven that if light is undulatory finite intervals are the conditions upon 

 which the colors of the rain- bow depend. Light must be either undulatory or 

 corpuscular. We know it is not corpuscular. Maxwell's Electro-Magnetic 

 theory though altering our views on some points must nevertheless be undulatory 

 and depend on finite intervals for its explanation of the spectrum. 



ASTRONOMY. 



HOW TO TELL THE DISTANCE OF THE SUN.— THE TRANSIT OF 

 VENUS, DECEMBER 6, 1882. 



EDGAR L. LAPKIN. 



Rudimentary Principles. — If we divide a semi-circle by its radius the 

 quotient will be 3.1415926535. But in a semi- circumference there are: 



160 Degrees, divided by 3.1415926535= 57-2957795139 



10, Soo Minutes, " " " =^ 3,437.74677 



648,000 Seconds, " " " =206,264.80625 



That is, a radius of any circle contains in terms of the circumference in round 

 numbers 57 degrees, 3437 minutes, or 206,264 seconds. These are among the 



