A bubble chamber experiment is described using data from the C.E.R.N. 2m bubble chamber filled with deuterium and exposed to a 4 GeV/c \(π^+\) beam. Measurements are presented of the U.5. \(π^+\) beam momentum, and the level of contamination in the beam is estimated. A brief review is given of the computer programs used in the processing of 2m bubble chamber film for physics analysis. The channel \(π^+d \rightarrow p_s p π^+ π^- ( \sigma = 2.10^±0.17m b) \) (1) is investigated and cross sections are obtained for the quasi-two-body reactions \(π^+d \rightarrow p_s p \rho^0 ( \sigma = 1.21^±0.16m b) \) (2) and \(π^+d \rightarrow p_a p f^0 ( \sigma = 0.53^±0.06m b) \) (3) An Estabrooks and Martin amplitude analysis is made of reaction (2) using 5279 events from the mass interval \(0.68