hi!
i think i can explain a little bit about ゐ ヰ ゑ ヱ ヲ を.
Ancient Japan had more vowel pronunciation than present Japan.
hiragana=ゐ ゑ を , katakana = ヰ ヱ ヲ
(Wi)ヰ=ゐ , (We)ヱ=ゑ , (WO) を=ヲ
ゐ ヰ ゑ ヱ were unified at recent years, even notation .
They are rarely found in the name of goods and company from around the 19th century.
old ヰスキー (wiskii/whiskey)
now ウィスキー
old ゑびす (webisu/a name of one of seven fortune gods )
now えびす (ebisu)
the pronunciation of ヲ を became "O" (sometimes Japanese people may be having pronounced while not noticing)
But the notation of ヲ を are still large activity.
For example,
私 を およがせて。 watashi -- "o" -- oyogasete / let me swim.
犬 を 連れていく。 inu o tureteiku / (It) take(s) a dog.
I am sorry to be strange English.