What is the main topic of Bulugh al-Maram Hadith 79?

Bulugh al-Maram Hadith 79 is from chapter "The Book of Purification". Summary: At-Tirmidhi's version has "using soil at the first or last time" .

Bulugh al-Maram: Hadith 79

1. The Book of Purification

1/6 Chapter:

باب نواقض الوضوء

Bulugh al-Maram

وَلِلتِّرْمِذِيِّ: { أُخْرَاهُنَّ, أَوْ أُولَاهُنَّ بِالتُّرَابِ } (17)‏ .‏

At-Tirmidhi's version has "using soil at the first or last time" .

Reference: Bulugh al-Maram 10
In-book : Book 1, Hadith 13
English translation : Book 1, Hadith 12