The action was even steamier in the thinly traded Resorts class 'B' shares. 6, resorts 'A' when-issued stock meanwhile climbed 8 1/4 to 64 1/2 in its second trading day. With a 3-for-1 stock split declared for Oct. Its low for the year is 15 and two years ago it was trading at just over $2 a share. Resorts class 'A' stock jumped 23 points to 190, following a gain of 17 points on Tuesday and 15 points on Wednesday. Resorts International, which is so far the only company with an operating casino in Atlantic City, saw its stock score the most sensational gains yet in what was already the stock market's highest flying performance of 1978, defying predictions that its bubble is due to burst. While the 'Blue Chips' and the rest of the market fizzled, the gambling chips' or casino issues continue to sizzle yesterday in what is the markets biggest speculative run-up in years.
