אורח חיים רס״הOrach Chayim 265

Se’if 1א׳

אֵין נוֹתְנִין כְּלִי מְנֻקָּב מָלֵא שֶׁמֶן עַל פִּי הַנֵּר כְּדֵי שֶׁיְּהֵא נוֹטֵף בְּתוֹכוֹ, גְּזֵרָה שֶׁמָּא יִסְתַּפֵּק מִמֶּנּוּ וְיִתְחַיֵּב מִשּׁוּם מְכַבֶּה; וְאִם חָבְרוּ לוֹ בְּסִיד אוֹ בְּחַרְסִית, מֻתָּר דְּכֵיוָן שֶׁהוּא כְּלִי אֶחָד בָּדִיל מִנֵּיהּ מִשּׁוּם אִסוּר שַׁבָּת.

The Laws Pertaining to Utensils Placed Below the [Shabbos] Light, 4 Seifim: It is forbidden to place a container filled with oil that has a drainage hole positioned over the opening of the [Shabbos] lamp so that the oil will continuously drip into the lamp. This is a decree lest one use some of the oil in the container, [and was imposed] since [the container] is not connected to the lamp. [Taking and using the oil would] constitute [a violation of] the prohibition [against] extinguishing [a fire]. If, however, the container was joined to the lamp in an effective manner, with lime or with plaster, it is permitted. Since they are joined together, they are considered a single utensil and the person will distance himself from the container because of the Shabbat prohibitions.

Se’if 2ב׳

לֹא יְמַלֵּא קְעָרָה שֶׁמֶן וְיִתְּנֶנָּה בְּצַד הַנֵּר וְיִתֵּן רֹאשׁ הַפְּתִילָה בְּתוֹכָהּ בִּשְׁבִיל שֶׁתְּהֵא שׁוֹאֶבֶת, גְּזֵרָה שֶׁמָּא יִסְתַּפֵּק מִמֶּנּוּ.

A person may not fill a bowl with oil and place it next to a lamp and then put one end of the wick in [the bowl] so that [the wick] will draw after it the oil in the bowl, lest he make use of the oil in [the bowl].

Se’if 3ג׳

אֵין נוֹתְנִין כְּלִי בְּשַׁבָּת תַּחַת הַנֵּר לְקַבֵּל שֶׁמֶן הַנּוֹטֵף, מִפְּנֵי שֶׁהוּא מְבַטֵּל כְּלִי מֵהֵיכָנוֹ; וּמֻתָּר לִתְּנוֹ מִבְּעוֹד יוֹם, וְהַשֶּׁמֶן הַנּוֹטֵף אָסוּר לְהִסְתַּפֵּק מִמֶּנּוּ בְּשַׁבָּת. הַגָּה: וְאָסוּר לִגֹּעַ בְּנֵר דּוֹלֵק כְּשֶׁהוּא תָּלוּי, אַף עַל פִּי שֶׁאֵינוֹ מְטַלְטְלוֹ וְאֵין בּוֹ מִשּׁוּם מֻקְצֶה בִּנְגִיעָה בְּעָלְמָא, מִכָּל מָקוֹם אָסוּר פֶּן יִתְנַדְנֵד קְצָת מִנְּגִיעָתוֹ וְיִטֶּה (אוֹר זָרוּעַ).

It is forbidden to place a container, on Shabbos, beneath an (oil) candle to catch the dripping oil, because one is revoking the use of the Keli. However, it is permitted to place it there before Shabbos. One may not use the dripping oil on Shabbos. Rema: It is forbidden to touch a lit (oil) candle when it is hanging, even though one does not move it – and there is no issur of Muktze just by touching, nevertheless it is forbidden lest it moves slightly and (will cause the flame to) tilt.