The choice of one or the other date decides whether it is proto-Sinaitic or proto-Canaanite, and by extension locates the invention of the alphabet in Egypt or Canaan respectively.

These ten inscriptions, plus an eleventh published by Raymond Weill in 1904 from the 1868 notes of Edward Henry Palmer,[17] were reviewed in detail, and numbered (as 345–355), by Alan Gardiner in 1916.

The Wadi el-Hol inscriptions strongly suggest a date of development of Proto-Sinaitic writing from the mid-19th to 18th centuries BC.

Some of the workmen employed by the Egyptians, probably the Aamu or Retennu – Syrians – who are often named, had this system of linear signs which we have found; they naturally mixed many hieroglyphs with it, borrowed from their masters.

In the winter of 1905, Flinders Petrie and his wife Hilda were conducting a series of archaeological excavations in the Sinai Peninsula.

[23] Ten years later, in 1916, Alan Gardiner, one of the premier Egyptologists of the early and mid-20th century, published his own interpretation of Petrie's findings, arguing that the glyphs appeared to be early versions of the signs used for later Semitic languages such as Phoenician, and was able to assign sound values and reconstructed names to some of the letters by assuming they represented what would later become the common Semitic abjad.

The two Wadi el-Hol inscriptions (Arabic: وادي الهول Wādī al-Hawl 'Ravine of Terror') were carved on the stone sides of an ancient high-desert military and trade road linking Thebes and Abydos, in the heart of literate Egypt.

[32] Rock inscriptions in the valley appear to show the oldest examples of phonetic alphabetic writing discovered to date.

This interpretation fits into the pattern in some of the surrounding Egyptian inscriptions, with celebrations for the goddess Hathor involving inebriation.

[33] Archaeological excavations at the site of Umm el-Marra have uncovered four inscribed clay cylinders dating to ca.

[34][35] In 2009, Stephanie Dalley published a number of tablets from the Schøyen Collection dating to the times of the First Sealand dynasty, four of which have been identified as examples of Early Alphabetic inscriptions.

[36] Other probable examples of Early Alphabetic inscriptions include an ostracon from a tomb in western Thebes and a inscribed sherd from Lachish, both dating to the 15th century BC.

[37][38][39] In 2010, Stefan Wimmer published an inscription discovered at Timna Valley which he also identified as written in the proto-Sinaitic writing, although he also noted that its authenticity is not certain.

[40] Below is a table synoptically showing selected Proto-Sinaitic signs and the proposed correspondences with Phoenician letters and Egyptian hieroglyphs.