Passed in 1870, the Prime Minister's Proclamation No. 57 had two provisions related to the national flag. The first provision specified who flew the flag and how it was flown; the second specified how the flag was made. The ratio was seven units width and ten units length (7:10). The red disc, which represents the sun, was calculated to be three-fifths of the hoist width. The law decreed the disc to be in the center, but it was usually placed one-hundredth () towards the hoist. On October 3 of the same year, regulations about the design of the merchant ensign and other naval flags were passed. For the merchant flag, the ratio was two units width and three units length (2:3). The size of the disc remained the same, but the sun disc was placed one-twentieth () towards the hoist.