Often, in after-times with her, did he recall this first magnetic night, and would seem to see that she then had bound him to her by an extraordinary atmospheric spell […]. This spell seemed one with that Pantheistic master-spell, which eternally locks in mystery and in muteness the universal subject world, and the physical electricalness of Isabel seemed reciprocal with the heat-lightnings and the ground-lightnings nigh to which it had first become revealed to Pierre.
Source: wiktionary