Then cover it with a sheet of lead [sisaka]. Then attach a sheet of lead (sisaka) to it, since lead will make the hole wider. Fix the sheet as one would fix a palm leaf. The hole will rapidly get wider.
english translation
तत्पश्चात् शीशम के पत्तों की कर्णिका से इसे बढ़ाना चाहिये ॥ २१ ॥
Then cover it with a sheet of lead [sisaka]. Then attach a sheet of lead (sisaka) to it, since lead will make the hole wider. Fix the sheet as one would fix a palm leaf. The hole will rapidly get wider.
english translation
तत्पश्चात् शीशम के पत्तों की कर्णिका से इसे बढ़ाना चाहिये ॥ २१ ॥