Show UNION mUON LEADERS PLEASED AT PROSPECTS OF PROBE HOUGHTON HOUGHTO- l Mich leh Jan 23 Union 23 Union le leaders ders In the copper district seemed pleased today at the prospect pro prospect p t of or a a. federal federal fed fed- eral investigation of ot tho a strike of or the miners which has been in progress since last summer Authorities today continued their Ine In Investigation In In- e of ot the leaving of ot a can of nitroglycerin In a a. clump of or bushes near neal the power plant of or the Ahmeek mine mina in Keweenaw county but bul no arrests had bO boon 11 made |