Mishnayos Rosh Hashanah Perek 2 Mishnah 3

The mishna asks: How would they light the torches during that earlier period? They would bring items that burn well, e.g., long poles of cedar, reeds, pinewood, and beaten flax, and tie them together with a string. And someone would then ascend to the top of the mountain and light the torch on fire with them, and wave it back and forth and up and down, until he would see his colleague doing likewise on the top of the second mountain. In this manner he would know that the next messenger had received the message and passed it on. And similarly, the second torchbearer would wait for a signal from the one on the top of the third mountain, and so on. In this manner the message would reach the Diaspora.

כֵּיצַד הָיוּ מַשִּׂיאִין מַשּׂוּאוֹת, מְבִיאִין כְּלֻנְסָאוֹת שֶׁל אֶרֶז אֲרֻכִּין וְקָנִים וַעֲצֵי שֶׁמֶן וּנְעֹרֶת שֶׁל פִּשְׁתָּן וְכוֹרֵךְ בִּמְשִׁיחָה, וְעוֹלֶה לְרֹאשׁ הָהָר וּמַצִּית בָּהֶן אֶת הָאוּר, וּמוֹלִיךְ וּמֵבִיא וּמַעֲלֶה וּמוֹרִיד, עַד שֶׁהוּא רוֹאֶה אֶת חֲבֵרוֹ שֶׁהוּא עוֹשֶׂה כֵן בְּרֹאשׁ הָהָר הַשֵּׁנִי, וְכֵן בְּרֹאשׁ הָהָר הַשְּׁלִישִׁי: