INTERFERENCE OF LIGHT. 97 



bouring portions is, however, very sensible, and we shall 

 have occasion hereafter to study some important phenomena 

 to which they give rise. In the meantime, one remarkable 

 consequence of this explanation is obvious namely, that 

 if the alternate portions be, de, &c., whose effects are negative, 

 be stopped, the total effect will be augmented, and the result- 

 ing light increased by intercepting a portion of the wave. 

 We shall see hereafter that this startling conclusion is con- 

 firmed by experiment. 



