Halo Phenomena in Olaus Magnus’s Historia de Gentibus Septentrionalibus (Part 3)

Halo phenomena in Historia de Gentibus Septentrionalibus, Bk. 1, Ch, 16. Image from www.avrosys.nu

“And no wonder: since we are so constituted, that everyday things, even if they deserve our amazement, pass us by; on the other hand the slightest things if they spring up in an unfamiliar way, become a pleasant spectacle. (…) when anything varies from normality, everyone’s face is turned to the sky.” (Ch. 15.) No one who is interested in halos would say that Olaus Magnus, the 16^th century Swedish theologian was not right when he wrote this. Even nowadays, most people rarely look up, and they take the sky for granted. If however, there is a comet, eclipse or halo phenomenon which becomes hyped by the media, people’s head immediately turn up for at least a day or two. But why not longer? I’m always surprised.

We have arrived at the final post of our three-part series introducing Olaus Magnus’s description of halos in Historia de Gentibus Septentrionalibus (part 1, part 2). This 16th century work dedicates several chapters to halo phenomena and illustrates the descriptions with fine woodcuts. According to Olaus, halos tend to appear mostly on spring mornings, especially when the surface of the earth is covered by deep snow and they usually don’t last more than one and a half or two hours. As he states in Chapter 15, this is due to the fact that clouds tend to change very quickly: they either thin or thicken too much for these phenomena to be observed.

This latter statement is indeed a realistic one, but scientific accuracy is not a characteristic feature of Olaus’s work. Historia de Gentibus Septentrionalibus was printed just around the advent of the scientific revolution, in 1555, when interest in natural phenomena was growing. Olaus is a Renaissance author, who lays much emphasis on collecting and recovering the scientific knowledge of ancient writers. However – although he tries to explain the formation of halos – he does not venture into looking further than the sources of the Antiquity and contemporary superstitions. This becomes evident when he continues his argumentation about clouds: ‟(…) since they are caused by the reflection of the black clouds and the whiteness of the very thick snow which wholly covers the face of the earth, [halos] are chiefly seen in February and March, because of the distant, slanting position of the sun”

As for contemporary beliefs, in Chapter 15 he treats halos together with comets and talks about them as bad omen, signalling “change of existing order” and meaning “grievous prognostications”. He, however, does not elaborate on halos affecting social order; in these two chapters he mostly mentions them as signals of unfavourable weather. “The blacker clouds in the lower circle foretell that savager tempests are on their way” (Ch. 16).

Halo phenomena in Historia de Gentibus Septentrionalibus, Bk. 1, Ch, 15. Image from www.avrosys.nu

From the strange description that Olaus gives, and also from the woodcuts, it becomes evident that personally he never witnessed the appearance of such phenomena. ‟(…) one circle, spacious and entirely white forms in the clouds over the horizon, but with another on its inner edge, which is black from being more compressed in size. On their surface these very large circles have four lines, or round openings distinguished by their saffron colour; between these towards the south among white clouds that are filled with snow, appear two circles set opposite each other, one of which is black on its outer rim, and on the inner, white. The other, lower circle, in the centre of which the disk of the sun is seen (this is intersected by the upper circle, which has a different centre) is white on the outer rim and dark on the inner, though the nearer the sun it lies, the whiter it is. Moreover, opposite the sun, round about the centre of the very large circle which spreads, as I said, over the horizon, there appears a bow lying diagonally, with colours like those of a rainbow, amid thick clouds, reddish on the outside, purple or saffron-yellow in the middle, and green below.” (Ch. 15)

Olaus’s Historia was written several decades before the three famous historical displays that marked a milestone in halo-science. It was the Rome displays of 1629 and 1630 which aroused the interest of Descartes so much that he decided to turn to halos. His publication of Les Météores in 1637 meant the first step towards a modern explanation of halo formation. Mathematical and physical approach to halos only started with his work and (after the 1661 Danzig display) it was further elaborated by the Dutch Christiaan Huygens. When reading Olaus Magnus’s Historia, we should not forget that at the time of its publication, the real scientific revolution was yet to come.

By Ágnes Kiricsi

English translation by Peter Fisher and Humphrey Higgens from: Olaus Magnus, A Description of the Northern Peoples, 1555, Vol. 1. Ed.: Peter Foote, Hakluyt Society, 1996.