-4- Division, obstruct tho visibility of another sign. Fo Ho billboards, signs or ether advertising devices shall be located nearer to other billboards, signs or other advertising devices than fifty (50) feet, unless said billboards, signs or other advertising devices aro placed back to back® Provided, howeirer, that his provision shall not npnly to districts which the Division may determine aro of a business character® Section 7. Removals® All billboards, signs or other advertising devices, except those exempted by Sections 50 and 52 of Chapter 95 of the General Laws, whether erected prior to the adoption of these rules and regulations or not, unless maintained under s Permit issued pursuant thereto, shall be removed on or hofo :e the Mrst day of July, 1925, unless the 'Division shall extend the time of such removal; not, in c.ny orent, e*;. 5 : • rortisj ?icef ex- cept those qxoj.5 vjori by foot;] onJ' h hf :f ihryyhof *’*•*0 Oaneral Iiaws9«« fa) V-/;lthin fifty foO) *-«ot o ■ 77 public vcy; (j) V/5 thin throe hm iyo-■ (•■.*■•>} ';• i>r • ny pr.blic perl, j ly- ground or other •1:10 ;rcr :1: rifhi:i vj v :M portion the