Colophon

Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects.

The bird on the cover of Mastering Perl/Tk is an emu (Dromaius novaehollandiae). This large, flightless bird is found throughout the Australian bush steppes. The emu is one of the largest birds in existence, second only to its cousin, the ostrich. Adult emus stand about 5 feet high and weigh up to 120 pounds. The grayish-brown emu's small wings contain only six or seven feathers. They are hidden by the long, hairlike rump plumage. Emus have extremely long legs, which they use as defensive and offensive weapons when fighting. A human limb can be broken by a kick from an emu. Their powerful legs make emus strong swimmers and fast runners; they can reach speeds of up to 50 kilometers per hour.

Male emus, which are slightly smaller than females, tend to the incubation of eggs and the raising of the young. An emu nest contains as much as fifteen to twenty-five deep green eggs, laid by several hens. Incubation of the eggs takes from twenty-five to sixty days. The large discrepancy in incubation time occurs because the male needs to leave the nest periodically to find food and drink. The length of time he is away affects the time for incubation. Newly hatched emus weigh about 15 ounces. They are fully grown at two to three years.

The relationship between emus and Australian farmers has always been adversarial; three coastal subspecies of emu have been exterminated. Because emus can jump over high fences, it is difficult to keep them out of fields, where they eat and trample crops. In the arid Australian bush, emus also compete with cattle and sheep for grass and water. On the other hand, emus eat many insects that would otherwise eat crops. In 1932, Australian farmers declared war on the emus, making an all-out effort to eradicate them. Fortunately, the effort failed. The battle between emus and farmers continues to this day.

Linley Dolby was the production editor and copyeditor for Mastering Perl/Tk. Sada Preisch was the proofreader. Jeffrey Holcomb and Claire Cloutier provided quality control. Lucie Haskins wrote the index. Phil Dangler, Derek Di Matteo, Edie Shapiro, and Sarah Sherman provided production support.

Pam Spremulli designed the cover of this book, based on a series design by Edie Freedman. The cover image is a 19th-century engraving from Johnson's Natural History II. Emma Colby produced the cover layout with QuarkXPress 4.1, using Adobe's ITC Garamond font.

Melanie Wang designed the interior layout, based on a series design by David Futato. Neil Walls implemented the design in FrameMaker 5.5.6, using tools created by Mike Sierra. The text font is Linotype Birka; the heading font is Adobe Myriad Condensed; and the code font is LucasFont's TheSans Mono Condensed. The illustrations that appear in the book were produced by Robert Romano and Jessamyn Read, using Macromedia FreeHand 9 and Adobe Photoshop 6. This colophon was written by Clairemarie Fisher O'Leary.