Chapter 18, Section 2 (פֶּרֶק י״ח אוֹת ב׳)

2. And rivers of fire beside their troughs (ב. וּנְהָרֵי אֵשׁ בְּצַד אָבוּסֵיהֶם), and all their horses would drink (וְהָיוּ שׁוֹתִים כָּל סוּסֵיהֶם), in the measure of the water-channel that is in the Kidron Valley (כְּשִׁעוּר אֶמֶת הַמַּיִם שֶׁיֵּשׁ בְּנַחַל קִדְרוֹן), which drains and sustains all the rainwaters of Yerushalayim (שֶׁמוֹצִיאָה וּמְחַזֶּקֶת כָּל מֵי גְשָׁמִים שֶׁל יְרוּשָׁלַיִם). And there was a cloud above their heads (וְהָיָה שָׁם עָנָן לְמַעְלָה מֵרֹאשָׁם), sprinkling blood over the heads of them and their horses (מְזַלֵּף דָּם לְמַעְלָה מֵרֹאשָׁם שֶׁלָּהֶם וְשֶׁל סוּסֵיהֶם). And this is the sign and measure (וְזֶהוּ סִימָן וּמִדָּה), of the gatekeepers of the entrance to the seventh Heichal (שֶׁל שׁוֹמְרֵי פֶתַח הֵיכָל הַשְּׁבִיעִי), and the horse of each gate and gate (וְסוּס כָּל פֶּתַח וָפֶתַח), of each and every Heichal (כָּל הֵיכָל וְהֵיכָל).