The next section of the Lincos dictionary introduces a word for second, "Sec," by playing pulses of various lengths, followed by Sec, and the number of seconds, "until the receiver may be expected to remark that the numbers... are proportional to the durations,"[2] thus teaching both that Sec is a unit of time, and exactly how long it is. He then introduces means for measuring durations, referring to moments in time, and talking about past and future events.