it is to be understood that the casing 56 can vary in size at different depths in the well 52 as would occur by assembling tubulars with different diameters for example the casing 56 can comprise a telescoping structure in which the size thereof decreases with increasing depth based on an open hole well log 36 fig1 or other information it is determined that zone f of the well 52 may contain oil and gas it is thus desired to perforate the casing 56 proximate to zone f to establish fluid communication between zone f and the inside diameter of the well casing 56 for performing the perforating process the system 50 includes a perforating tool 68 and a reader device 70 in signal communication with the perforating tool 68 the system 50 also includes a plurality of identification devices 72 fig3 d attached to the collars 64 on the casing 56 and readable by the reader device 70 in addition the system 50 includes a transport mechanism 66 w for transporting the perforating tool 68 and the reader device 70 through the well casing 56 to zone f if desired the system 50 can be transported to the well 52 as a kit and then assembled at the well 52 as shown in fig3 c the perforating tool 68 includes a detonator 74 illustrated schematically and a detonator cord 76 in signal communication with the detonator 74 the detonator 74 can comprise a commercially available impact or electrical detonator configured for actuation by a signal from the reader device 70 similarly the detonator cord 76 can comprise a commercially available component the detonator.