Hodgson, [75].
Holtz, [94].
Huggins, [9], [55], [61], [79], [109], [158], [163], [181], [205], [212], [213], [214], [216], [217], [235], [254], [255], [258].
Huygens, [265].
Indian sources, [316].
Janssen, [49].
Jouvencel (De), [318].
Kant, [35].
Kelvin (Lord), [38].