The first scientific report on Stonehenge was made by Inigo Jones, at the wish of James I.; he thought it was a temple erected by the Romans, after the Tuscan order. Charleton, physician to Charles II., held that it was a monument of the Danish period. Aubrey, about the same time, attributed it to the Druids. Next came Stukeley's famous theory. Stukeley, a man of great learning, had read of the Druids, and had seen the circles; then he found a grotesque story in Pliny about an egg, miraculously produced from the saliva of serpents, and regarded as a charm by the Druids. So, he reasoned, the Druids made the circles for serpent worship; and, according to his argument, the complete temple consisted of a diagram of a snake, miles long, done in boulders, the circles being the reptile's coils! To demonstrate this, Stukeley made a plan of the Avebury remains. The result was not very convincing; essential parts of the creature's anatomy were wanting; and a snake is nothing if not continuous. But he sketched in these missing parts out of his own head, and the thing was done. Somewhat similar results were got from a hurried survey of Shap, about 1725. Such is the groundwork of the popular belief in "Druids' Circles," and yet, at the time, it was received almost as a revelation. John Wood, of Bath, about 1747, introduced the idea that the numbers of the stones corresponded to certain astronomical cycles or periods of time. Rev. Edward Duke, writing in 1846, saw in the Wiltshire remains a vast plan of the solar system as known to the ancients; the small circles at Avebury were the sun and moon at the summer solstice; the avenue of stones on either side was the northern portion of the ecliptic; Silbury Hill, a mile south, the Earth. Four miles north of Silbury, Winterbourne Basset circle stood for the planet Venus; south of it were Mercury; Mars; Jupiter, represented by Casterly Camp, nine miles from Silbury; and Saturn by Stonehenge, sixteen miles off. The vastness of the scheme will be appreciated by saying that an equivalent of this in Westmorland would place Saturn at Tebay, Jupiter at Shap, and the Earth at Eamont Bridge; or, following the railway, the viaduct crossing the Eamont. Mr. Duke notices that all the points are in almost exact line due north and south; and that Stonehenge points directly towards the sunrise at the summer solstice. About twenty years later, a good deal was made of practically the same fact, that from the so-called Altar Stone within Stonehenge, the sun on Midsummer Day appears to rise immediately over a distant stone called the Friar's Heel; hence it is argued that Stonehenge was an observatory. This is the modern popular theory, possibly because of its simplicity. Fergusson, about 1870, published a most interesting argument that these circles were set up after the Romans left; his conclusion is not generally accepted, though his views are treated with respect.