Dr Walter Gorn Old (born 20 March 1864, at 2:06 a.m. LMT in Handsworth, England died 23 December 1929 in Hove, England) was a notable 19th century astrologer, better known as Sepharial.

Sepharial was in fact one of the founder members of the Theosophical movement in England. Madame Blavatsky (whom he lived with until her death) called him "The Astral Tramp" because of his nightly explorations into the astral plane.

Sepharial became a very influential author in the fields of the occult, astrology and numerology, and his writings had a considerable impact on E. H. Bailey and Alan Leo, who he introduced to Theosophy. He can be credited as the first astrologer to use Earth's "dark moon" Lilith in his calculations. Genuinely erudite, Sepharial had for example a greater knowledge of mathematics, astronomy, and historical methodology than most of his astrological contemporaries and this showed in his writings. Sepharial's "Degrees of the Zodiac Symbolised" (co-written with Charubel) foreshadowed Marc Edmund Jones's subsequent (and nowadays better known) work on Sabian Symbols. However, many of his books and other works were put together in a rather slapdash way, which made his reputation less enduring than it might have been. A colourful character, Sepharial started a number of astrological magazines, all of which failed to establish themselves