I am currently reading an early story by Tanizaki Junichiro in Japanese. I have come across both the hiragana く and ぐ written twice the size they usually are, taking up the same amount of space on the page as two characters. Is there any significance in this? 

These include words such as ひい<b>く</b>と and いろ<b>く</b>の注文, where the character in bold is written at twice the height as normal.

Any help would be most appreciated (^-^)