But their singing acts direct upon the upper, or spiritual centers in us. So does almost all our music, which is all Christian in tendency. But modern music is analytical, critical, and it has discovered the power of ugliness. Like our martial music, it is of the upper plane, like our martial songs, our fifes and our brass-bands. These act direct upon the thoracic ganglion. Time was, however, when music acted upon the sensual centers direct. We hear it still in savage music, and in the roll of drums, and in the roaring of lions, and in the howling of cats. And in some voices still we hear the deeper resonance of the sensual mode of consciousness. But the tendency is for everything to be brought on to the upper plane, whilst the lower plane is just worked automatically from the upper.