Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Harrison's H1: app and replica
    From: Frank Reed
    Date: 2013 Apr 7, 16:44 -0700

    Before yesterday, I did not know that there was an iOS app that displayed a simple virtual animation of Harrison's 1735 clock H1. And three days before that I would not have known that there's a recently-completed serious functioning replica of H1. When it rains time-keepers, it pours time-keepers.

    On Tuesday, I saw a notice for a presentation scheduled for two days later at Mystic Seaport on a fully-functional replica of Harrison's H1 built by Douglas Drumheller. If I had had more notice, I would have invited NavList members. As it happened Herbert Prinz just got back from his sailing trip from the Virgin Islands to the Galapagos, so he was available and also attended. The program was ostensibly about the "Discovery of Longitude" though on this score the presentation was pedestrian. Drumheller did not go beyond a brief recap of some general points found in Sobel's "Longitude" and unsurprisingly he repeated a couple of myths that are also found in that book. I went in fully expecting him to repeat the myth that it took four hours to work the calculations for a lunar. But he exceeded my expectations and stated that it took six hours to work a lunar! The presentation, however, was really just preamble for a discussion of his marvelous creative obsession of the past 15 years: the construction of a working replica of H1. He showed some beautiful photos of it and some fascinating video. It really does function or "go" as clock people say. He hopes eventually to sail it across the Atlantic on a tall ship.

    Meanwhile, I've downloaded the H1 Sea clock app for my iPad. This is a very basic animation. It's essentially a photo of H1 with a few simple 2d animated components. The animation of the rocking pendula is very nice, while the ticking animation of the main gear leaves something to be desired. The sound of the movement is apparently recorded from Harrison's H1 itself, so it has an authentic sound to it. Of course, H1 does not sound the hours with the nautical pattern of bells. That feature is just for fun. The clock is not a 3d representation. There is a static perspective view, but this is just a cleaned up photo. The app also includes a video of Jonathan Betts describing H1. He is the true expert these days on Harrison's clocks at the National Maritime Museum. Get a copy of his little book "Harrison" if you don't have it. The app is well worth its price of 99 cents. Good fun.


    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]fer3.com

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site