Extract from a letter addressed to Dr. F. A. Jentink

»I take advantage of this opportunity to send you a small box containing a piece of a telegraph pole (of djatiwood, Tectona grandis) with two Wood-peckers, Picus analis, from Java, Kediri Residency. These birds make, as you see, rather large holes in the teakwood, which is as hard as iron, near the point where the isolator has been attached: apparently because they mistake the well known buzzing of the quavering wire-threads of the telegraph for the gnawing and boring of Insects. I should not have mentioned this fact if it was not such a great rarity. For on the Paris electricity exhibition in 1881 there was to be seen as a great rarity a telegraph pole perforated through and through by a hole having a diameter of 7 centimeters: this remarkable pole was sent by the Director of the Norway telegraphs. The administration for a long time was uncertain to what cause ascribe this damage done to poles which for the rest were entirely sound, till at last by a mere chance the Wood-peckers were seen at work.