I thought it would be fun to use the amazingly accessible digitized Codex Sinaiticus as I work on my Hebrews chapter. Whether anything from this exercise will impact my dissertation or not, I do not know, but I thought it would be good experience to read it from an ancient witness in addition to and in contrast with (wherever relevant) the conflated Nestle-Aland text.
So, for the opening lines of Hebrews (coming on the heels of a portion of 2 Thessalonians), go here. Hebrews begins at the top of the fourth column. You might notice an interesting aspect of the codex here--often the last letter in the line of a column is dropped or minimized. For example ΤΟΥΣ ΑΙΩΝΑΣ looks more like ΤΟΥ ΑΙΩΝΑΣ where the masculine accusative plural ends the column line. You will also notice that, typical of its time, the capital sigma looks more like our C and their capital Ω looks like a bigger lowercase ω. You can even see some ancient editing at work where ΗΜΩΝ is indicated in the left hand margin in a different hand (notice the Ω is different-in the text it has a single bump on the bottom, where as in the margin it has a doubly curved bottom) with a little squiggle (that's my technical term for it) and an identical squiggle appears in the place in the line where it should be. Critical editing marks haven't changed that much over the millenia, have they? Overall it is a beautiful, regular script, clearly written by a steady hand, although the titles are clearly written in a different, less steady hand. You might also notice on the left hand margin of each column, that the scribe does sort of a reverse indentation. It seems to indicate new thought units (longer clauses, sentences, paragraphs). Overall, it is good practice to look at an ancient witness to remind ourselves that they lack punctuation (for the most part), accentuation, and, most importantly, spacing between words!
Have fun playing with this fantastic online tool!