Kyūjitai form of 私鉄 (“private railway”)

水入らず: just among the immediately relevant people, without anyone else

水色: sky blue, turquoise blue, light blue, aqua blue

民間: private

見た: saw

海松: a type of seaweed / 水松: a type of seaweed

見る: to see / 看る: to look after, take care of / 観る: to view (flowers, a movie) / 視る: to see (an area struck by a disaster) / 診る: to examine (medical) / 回る: to turn, revolve / 廻る: to turn, revolve

手紙: letter

ミズ: Ms

見ず: without seeing, negative continuous form of 見る