Huygens represents the propagation of light with expanding partial waves that are used to construct the wave DCF (fig 1).
"There is the further consideration in the emanation of these waves, that each particle of matter in which a wave spreads, ought not to communicate its motion only to the next particle which is in the straight line drawn from the luminous point, but that it also imparts some of it necessarily to all the others which touch it and which oppose themselves to its movement. So it arises that around each particle there is made a wave of which that particle is the centre. Thus if DCF is a wave emanating from the luminous point A, which is its centre, the particle B, one of those comprised within the sphere DCF, will have made its particular or partial wave KCL, which will touch the wave DCF at C at the same moment that the principal wave emanating from the point A has arrived at DCF; and it is clear that it will be only the region C of the wave KCL which will touch the wave DCF, to wit, that which is in the straight line drawn through AB. Similarly the other particles of the sphere DCF, such as bb, dd, etc., will each make its own wave. But each of these waves can be infinitely feeble only as compared with the wave DCF, to the composition of which all the others contribute by the part of their surface which is most distant from the centre A." (Huygens, p. 19).
Huygens' expanding partial waves KCL originate from points b, b, b, along the wave HI. The far points C, C, C, of the expanding partial waves KCL, are used to construct the wave DCF which represents Huygens' propagation mechanism of light but Huygens' wave HI is arbitrary creating energy (partial waves), from points b, b, b, along the wave HI, away from the light source, which violates energy conservation. In addition, only the far points C, C, C, of the partial waves KCL, are used to construct the wave DCF. For every partial wave used to construct the wave DCF, the partial waves' structures between K and C, and between C and L, are destroyed, after the wave DCF is constructed. An enormous amount of energy (partial waves) is created then destroyed in Huygens' propagation mechanism of light.
"There is the further consideration in the emanation of these waves, that each particle of matter in which a wave spreads, ought not to communicate its motion only to the next particle which is in the straight line drawn from the luminous point, but that it also imparts some of it necessarily to all the others which touch it and which oppose themselves to its movement. So it arises that around each particle there is made a wave of which that particle is the centre. Thus if DCF is a wave emanating from the luminous point A, which is its centre, the particle B, one of those comprised within the sphere DCF, will have made its particular or partial wave KCL, which will touch the wave DCF at C at the same moment that the principal wave emanating from the point A has arrived at DCF; and it is clear that it will be only the region C of the wave KCL which will touch the wave DCF, to wit, that which is in the straight line drawn through AB. Similarly the other particles of the sphere DCF, such as bb, dd, etc., will each make its own wave. But each of these waves can be infinitely feeble only as compared with the wave DCF, to the composition of which all the others contribute by the part of their surface which is most distant from the centre A." (Huygens, p. 19).
Huygens' expanding partial waves KCL originate from points b, b, b, along the wave HI. The far points C, C, C, of the expanding partial waves KCL, are used to construct the wave DCF which represents Huygens' propagation mechanism of light but Huygens' wave HI is arbitrary creating energy (partial waves), from points b, b, b, along the wave HI, away from the light source, which violates energy conservation. In addition, only the far points C, C, C, of the partial waves KCL, are used to construct the wave DCF. For every partial wave used to construct the wave DCF, the partial waves' structures between K and C, and between C and L, are destroyed, after the wave DCF is constructed. An enormous amount of energy (partial waves) is created then destroyed in Huygens' propagation mechanism of light.
