in the room of śa preceded by a surd Mute, there is optionally the letter ch when a vowel or ya, va or ra follows such śa,
Though झय् means all Mutes, the rule, however, applies to surd mutes. The words झय् and अन्यतरस्यां are to be read into the sutra. Thus वाक् + शेते = वाक्छेते or शेते ॥ अग्निचिच्छेते or अग्निचित् शेते, श्वलिट् शेते or छेते, त्रिष्टुप्छेते or शेते ॥
Vart:- It should rather be stated when a letter of the अम् pratyahara follows. The sutra only gives अट् letters, the vartika adds the letters ल, and the nasals. Thus तत् श्लोकेन = तच् छ्लोकेन, तच्छ्मश्रुणा ॥,