Trowbridge — New Emission Theory of Light. 51 



Art. VII. — A New Emission Theory of Light; by John 



Trowbridge. 



It is interesting to imagine how Sir Isaac Newton would 

 have rehabilitated his corpuscular Theory of Light if the Elec- 

 tron Theory had been enunciated during his lifetime. Might 

 he not have answered the objection to his theory that light 

 travels slower in fluids than in air by the assumption that the 

 infinitely small electrons could pass between the atoms of the 

 fluid and in so doing give up a portion of their energy to these 

 atoms by setting them in vibration, thus producing absorp- 

 tion spectra which arise in all fluids on the transmission of 

 light. Might he not, also, if the vortex theory of motion had 

 engaged the attention of the mathematicians of his time, have 

 provided his corpuscles with a whirling or vortical motion ? 

 In the periodic motion of the negative electron along a helical 

 path, he could have supposed an apparent wave motion ; and 

 in the repulsion of neighboring vortices perhaps he could have 

 abolished the conception of an elastic ether. 



In thus imagining a new light dawning upon a mind which 

 was capable of penetrating great secrets of the universe, I am 

 emboldened to offer a hypothesis which may serve to lead us 

 back to an emission theory of light, and at the same time 

 enable us to relegate the ether to the phlogiston, the caloric, 

 and the two fluid theories of electricity. 



In the rough this theory supposes that negative electrons are 

 shot forth from the sun in helical vortices, and in their pro- 

 gression provide an apparent periodic wave motion, giving, 

 according to Maxwell's Electrodynamic Theory of Light, a 

 pressure in the line of propagation and a tension at right 

 angles to this line. A magnetic effect is a plane at right angles 

 to the electrostatic effect, a repulsion between neighboring 

 vortices which would simulate the supposed elasticity of an 

 ether. The circular helices might become elliptical helices in 

 passing through doubly refracting substances, and interference 

 of light could be provided for. In support of this theory it 

 may be urged that vortical motion is as common as rectilinear 

 motion. The observer of the sun's surface is as conscious of 

 vortex motion in the sun's spots as of the rectilinear uprush in 

 the protuberances. The atomic theories are being recast to 

 embrace the effect of supposed vortical motions. Speculation 

 has gone so far as to suppose that atoms are mere whirls in a 

 supposititious ether. A recent distinguished physicist has sup- 

 posed that the negative electron is not matter and is provided 

 with a vortex tail or tails to account for electrical lines of force. 

 In this hypothesis, we appear to have two intangible essences 



