Complex sentence: Kenney ordered Walker to try the instantaneous fuses for a couple of months, so that data could be gained about their effectiveness; a few weeks later Kenney discovered that Walker had discontinued the use of the instantaneous fuses.
Split into simpler sentences: Kenney ordered Walker to try the instantaneous fuses for a couple of months, so that data could be gained about their effectiveness. However, a few weeks later Kenney discovered that Walker had discontinued the use of the instantaneous fuses.