Reference for Tevul Yom 2:7
חָבִית שֶׁנִּקְּבָה בֵּין מִפִּיהָ בֵּין מִשּׁוּלֶיהָ בֵּין מִצִּדֶּיהָ וְנָגַע בּוֹ טְבוּל יוֹם, טְמֵאָה. רַבִּי יְהוּדָה אוֹמֵר, מִפִּיהָ וּמִשּׁוּלֶיהָ, טְמֵאָה. מִן הַצְּדָדִין, מִכָּאן וּמִכָּאן, טְהוֹרָה. הַמְעָרֶה מִכְּלִי לִכְלִי וְנָגַע טְבוּל יוֹם בַּקִּלּוּחַ, אִם יֶשׁ בּוֹ, יַעֲלֶה בְאַחַת וּמֵאָה:
Regarding a barrel which was pierced, whether at its mouth, its bottom, or its sides, if a <i>tevul yom</i> touched it, it is impure. Rabbi Yehuda says: if [it was pierced] at its mouth or its bottom is it impure; but if on its sides, from this side or that, it is pure. If one pours [<i>terumah</i> liquids] from vessel to vessel, and a <i>tevul yom</i> touched the stream [of liquid], if it [i.e. the lower vessel] contains [a sufficient amount of liquid], it [i.e. the part of the stream which the <i>tevul yom</i> rendered impure] is nullified at one-hundred to one.