Bromine was utilized in the presence of stoichiometric amount of pyridine to brominate silanic hydrogen of methylhydropolysiloxanes. Methylbromopolysiloxanes thus obtained and methylchloropolysiloxanes prepared from photo-chlorination of methylhydropolysiloxanes were hydrolyzed with or without methylchlorosilanes to yield new methylhydroxypolysiloxanes and branched methylpoly siloxanes. Preparation