A Dictionary of Greek and Roman Antiquities/Axones
AX´ONES (achunes) 
also called kurbeis, wooden tablets painted white, and made to turn on an upright axis, on which were written the laws of Solon. According to some writers, the kurbeis contained the public and religious, the achones the private laws; according to others, the kurbeis had three sides, and the achones four. But at Athens, at all events, they were almost certainly identical, according to the statement of Aristotle (ap. Plut. Sol. 25). The grammarians, indeed, insist on the difference; but the opinion of most modern scholars is in agreement with that already expressed in the former editions of this work. The phrase ek tôn kurbeôn thuein in Lysias (Or. 30, c. Nicom. § 17) has been relied upon by the advocates of the distinction. But the law of murder must have been a public and religious law: and this we find was en tôi achoni (Lex ap. Dem. c. Aristocr. p. 629, § 28: read en tôi a achoni, i. e. prôtôi achoni, with Cobet, Var. Lect. p. 123; the achones being always mentioned in the plural).
The words trigônoi and tetragônoi, used of the achones and kurbeis, have been wrongly explained by some authorities, both ancient and modern, as applying to the separate tablets, and not to the whole contrivance (kataskeuachma). The gloss in Timaeus has Kurbeis stêlê trigônos puranoeidês nomous echousa peri theôn (so also Bekk. Anecd. p. 274, trigônoi, puramidi homoioi). This pyramidal shape is accepted by Planck (ap. Pauly i,2 s. v. achones), and Liddell and Scott (ed. 7, s. v. kurbeis). But apart from its unsuitableness for exhibiting writings, the clear account of Aristophanes of Byzantium (in Etym. M. p. 547; cf. Ruhnken on Timaeus, s. v. ku?rbeis) leaves no doubt that the boards were rectangular, and formed, as Caillemer puts it, a prism (not pyramid) of three or four sides.
The achones were at first kept in the Acropolis, but were afterwards placed, at the suggestion of Ephialtes, in the agora for all to read. Some fragments of them were preserved in the prytaneium in the time of Plutarch (l. c.; cf. Paus. i. 18, 3). (Schol. ad Aristoph. Av. 1354; Schol. ad Apoll. Rhod. iv. 280; Anaximenes ap. Harpocrat. s. v. ho katôthen nomos: Etym. M. p. 547; Suid. s. v.; Hermann, Staatsalterth. § 107, 1; Schömann, Antiq. i. 329, n., E. T.; Preller, on Polemonis Periegetae fragm. pp. 87-91 [the fragment itself in Müller, Fr. Hist. iii. 138 a].)