CSS Floats: Rule 9
A left–floating element must be put as far to the left as possible, and a right–floating element as far to the right as possible. A higher position is preferred to one that is further to the right or left.
This final rule is also self–explanatory. However, let's consider the following left–floated images.
The second image is not set as far left as possible, since it could feasibly appear underneath the first floated image and against the left border. Instead, it is favoring a higher position over a farther left placient with relation to the previously floated image.

Helium were an American indie rock group formed (as Chupa) in the summer of 1992 by Mary Lou Lord, Jason Hatfield (Juliana's brother), Shawn King Devlin (drums) and Brian Dunton (electric bass guitar).[1] Devlin and Dunton were both also in the band Dumptruck at the time. Mary Timony (electric guitar and vocals, formerly of the band Autoclave) was recruited after Mary Lou was reluctant to go electric.

Their first release was a 7" single entitled The American Jean (1993), which was followed by the 7" Hole in the Ground. They released their first EP, Pirate Prude, in 1994. Shortly after the release of Pirate Prude, Dunton left the band and Polvo guitarist Ash Bowie (boyfriend of Timony at the time) joined on bass. In 1995, they released their first full–length release, The Dirt of Luck, and played the second stage of Lollapalooza. Two of the band's music videos (Pat's Trick and XXX) were critiqued by MTV's animated teen pundits Beavis and Butt–head. Adam Lasus produced and engineered The Dirt of Luck, Pirate Prude, and all the singles up to 1995.