Atonori - Afternoon

...One raft is called one bed or one group, and two to four rafts are lined up in a single file. Depending on the size of the raft, about two to three people can ride on it, and they are called Sakinori (also called Henori or Hananori), Nakanori, and Atonori (also called Tomonori) from the front, with the Sakinori handled by an experienced person. At the relay point where the river widens, the upstream raft is called the upper raft and the downstream raft is called the lower raft, and the lower rafts are often lined up in two to four files. ...

*Some of the terminology explanations that mention "Atonori" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…いかだ1枚を1床とか1房といい，2～4枚ほどを1列縦隊に並べる。いかだの大きさにもよるが，およそ2～3人乗りで，それぞれ前からサキノリ(あるいはヘノリ，ハナノリともいう)，ナカノリ，アトノリ(トモノリともいう)といい，サキノリは熟練者が当たった。川幅が広くなる中継地点を境に，上流を上いかだ，下流を下いかだともいい，下いかだは2～4列縦隊にもやう。…

※「アトノリ」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報