Bob Holmström, Editor, 2934 NW 53rd Drive, Portland, OR 97210 Phone: 503-292-3685, <holmstro@europa.com>

Bill Givens, Sec. &: Publisher, 3850 Ashford Dr., Eugene, OR 97405 Phone (H): 541-465-9311 <Lbanks@ix.netcom.com>

Everett Jones, Treas., Phone: 440-729-4811

Ernie Martt, Founding Editor, Phone: 440-247-6712, Phone: 440-247-6712 <emartt@oh.verio.com>

I asked in the last issue if there was interest in an issue of HSN relating to temperature correction devices and have gotten a positive response. I currently have commitments for 3 articles to be published in HSN 2000-3 - please contact me if you are interested in contributing additional material for this issue.

There are no new Rock the Boat items in this issue. These are meant to be comments no longer than half a page on horological topics, including controversial ones, but not personal. This is a quick way to write a short article, convey an important idea or ask a question.

Bob Holmstrom

Page Contents

1 Index of this issue.

2 - 5 Introduction to the Longnow Clock Project by Danny Hillis

6 - 7 Barometric compensation of a Crossed Spring Suspension by Robert Matthys

7 - 8 Effective Length of a Pendulum with Knife Edge Suspension by Ned Bigelow

9 - 10 The Spiral Hairspring by Kenneth Johnston

11 - 21 Pendulum Air Movement - A Second Try by Robert Matthys

22 - 24 The geometry of the Grasshopper Escapement: A Recalculation of Burgesses Figure 4. by Henry Casson

Above: Drawing from Apians Cosmographicus Liber of 1533, showing how a nocturnal is used to tell the time at night from the Great Bear.

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