The squeeze on traffic flow on Yonge St. caused by underground subway construction; will last even longer than expected as a result of a walkout by120 tunnellers protesting working conditions. This view; looking south on Yonge St.; just north of Eglinton Ave. shows the bottleneck as both north and southbound traffic is limited to single lanes. Union men walked off job because they object to working in the heavy air pressure; calling it a health hazard.