Only the chance sound had led him to observe them. 
oʊnli ðʌ tʃæns saʊnd hæd lɛd hɪm tu ʌbzɜ˞v ðɛm. 
 Indian's voice is very monotone and spoken at a moderate speed. The recording is of very good quality, with almost no noise present. The speech is delivered in a quiet environment, with no noticeable reverberation.