The outer portion of the CLEO detector was divided into independent octants that were primarily dedicated to charged particle identification. No clear consensus was reached on the choice of technology for particle identification, therefore two octants were equipped with dE/dx ionization chambers, two octants were equipped with high pressure gas Cerenkov detectors, and four octants were equipped with low pressure gas Cerenkov detectors. The dE/dx system demonstrated superior particle identification performance and aided in tracking, therefore in September 1981 all eight octants were equipped with dE/dx chambers. The dE/dx chambers measured the ionization of charged particles as they passed through a multiwire proportional chamber (MWPC). Each dE/dx octant was made with 124 separate modules, and each module contained 117 wires. Groups of ten modules were ganged together to minimize the number of readout channels. The first two and last two modules were not instrumented, therefore each octant had twelve cells. The time-of-flight detector was directly outside the dE/dx chambers. It identified a charged particle by measuring its velocity and comparing it to the momentum measurement from the tracking chambers. Scintillating bars were arranged parallel to the beamline, with six bars for each half of the octant. The six bars in each octant half overlapped to avoid having any uninstrumented regions. The scintillation photons were detected by photomultiplier tubes. Each bar was 2.03 m × 0.312 m× 0.025 m. The CLEO I muon drift chambers were the outermost detectors. Two layers of muon detectors were outside the magnet iron on either end of CLEO. The barrel region had two additional layers of muon chambers after 15 cm and 30 cm of magnet iron. The muon detectors were between 4 and 10 radiation lengths deep and were sensitive to muons with energies of at least 1-2 GeV. The magnet yoke weighed 580 tons, and each of four movable carts at each corner of the detector weighed 240 tons, for a total of 1540 tons. CLEO II used time-of-flight detectors between the drift chamber and the calorimeter, one in the barrel region, the other in the endcap region. The barrel region consisted of 64 Bicron bars with light guides leading to photomultiplier tubes outside the magnetic field region. A similar system covered the endcap region. The TOF system had a timing resolution of 150 cm. The central and endcap TOF detectors combined covered 97% of the solid angle. The CLEO I muon detector