Here is a Splitdorf catalog 52 for 1914. The magnetos are low tension devices meaning that they are low voltage generators that power an external step up transformer which produces the ignition voltage. The transformer or ignition coil is sometimes mounted on the dash with a kick switch and start button. In the start mode, battery power is supplied to the ignition coil using the breaker and distributor on the magneto. When (and if) the engine starts the dash kick switch is moved from the battery position to the magneto output. An interesting feature of this system is the presence of a small momentary push switch. This is a starting aid in the battery mode. It is connected across the breaker points as a rule. To use this feature, the engine is rolled to or slightly past top center and primed with the ignition switch off. In this position, the breaker points would have just opened. Once primed with ignition switch in the battery mode, pushing and releasing the button causes the coil to fire and hopefully start the engine.
Problems areas of this arrangement: many. Few problems with the low tension side of the circuit aside from mechanical wear and suicidal pot metal. The windings and insulation are heavy and usually survive well. Most of the googlies and boogers lurk inside the coil/switch/ assembly. The interconnecting wires are often in rough shape and need to be replaced. A custom harness matching the original wires and colours makes a nice installation. Wire colours can fade over time but may be discernable inside the coilbox.
The ignition condenser or capacitor for electrical engineers is usually buried inside the coilbox. Early condensers were insulated with paper and wax or tar and do not improve with age. The ignition coil is also insulated with paper, tar and wax subject to the same fate. Bad condensers and coils are almost always present. The wood coil boxes of the day can warp and come apart as well. To recondition the coilbox one must very carefully melt out the tar or wax in an oven. When all is well and in good repair they work reasonably well. There is a hot spark even at low cranking speeds.