If this is the bowl by Kaj Franck (and it looks like that to me) it is made as a kind of industrial ariel in that the glass was first blown into a mold to make the deep lines (rather than cutting them or sandblasting them as would have been done with ariel glass) and then the second layer of glass is cased over the grooved glass creating the long thin bubbles. It is done by hand of course and is not easy, but it is not ariel as it was done by Orrefors. I think Orrefors sent somebody over to look at the process to make sure it was not the same, because it looks so similar. In fact functionally it is the same. In a way, it is similar to the controlled bubbles in Gunnel Nyman's Huntu pieces in that they are first blown into a spiked mold and then cased, leaving the holes from the spikes as tiny bubbles. And the acid signature dates it to 1953 or before, as I understand. And the "smokey" treatment may also be the same kind of technique used by Nyman in some of her glass, where actual smoke was used in the process.