Wettstein inaugurated the modern method of classification. He used capital Latin letters to identify the uncials. Codex Alexandrinus received the letter "A", Codex Vaticanus – "B", Codex Ephraemi – "C", Codex Bezae – "D", until he arrived at the last letter used by him, "O". Succeeding generations used this pattern, but newly discovered manuscripts soon exhausted the Latin alphabet. As a result, letters of the Greek and Hebrew alphabets began to be used. Tischendorf, for example, assigned the Codex Sinaiticus the Hebrew letter א. Uncial 047 received siglum ב1, Uncial 048 received ב2, Uncial 075 received ג, Codex Macedoniensis – ו, to name a few. When Greek and Hebrew letters ran out, Gregory assigned uncials numerals with an initial 0 (to distinguish them from the symbols of minuscule manuscripts). Codex Sinaiticus received the number 01, Alexandrinus – 02, Vaticanus – 03, Ephraemi – 04, etc. The last uncial manuscript known by Gregory received number 0161. Ernst von Dobschütz expanded the list of uncials through 0208 in 1933.