Month: September 2010

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BRVNHC Review

Mike of the Further In & Higher Up blog has over a hundred posts about National Park Service places. Last month he posted about his experiences in the Blackstone River Valley National Heritage Corridor. It’s a good read I recommend it. He gives the BRVNHC an overall rating of 3 out of five “very interesting”, better than average. I was a little surprised that Slater Mill wasn’t suggested as the place to start a tour when he was at the Roger Williams National Memorial. I suspect if he had visited Slater Mill the “Significance” rating of 2, “debatable that this had to be preserved” might have been higher.

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Google Earth News & Map Data Sources

I’ve been using Google Earth version 5.2.1.1329 (beta) for some time and I find the measurement tab of the path properties dialog very useful. Another very handy feature appears when you right click on a path, the Show Elevation Profile option creates a nice interactive elevation chart.

I stumbled upon a good resource for free online historical maps the other day, Maps ETC from the University of South Florida. In addition to the nice maps they also provide some good basic tutorial videos for Google Earth.

While I was updating some of my Blackstone Valley places files I discovered the Map of all coordinates from Google link on a Wikipedia National Register of Historic Places list article. Clicking the link plots all the sites in Google Maps, but if you click the show link over to the right you get more mapping options. One of the options, Export all coordinates as KML, lets you load the place locations directly into Google Earth.

I decided to load up all the Wikipedia data for Massachusetts and Rhode Island, wow, there are a lot of sites. So I made a version limiting the places to those that fall within the boundary of the Blackstone River Valley National Heritage Corridor.

Most of the sites are not positioned precisely so, I’m tweaking the positions as I work on exploring the BRVNHC. During a recent editing session I found that the National Register of Historic Places provides Google Earth files with some locations updated with more accurate TeleAtlas data. Loading these files along with my my custom file helps in locating the historic sites.

One feature I’m editing into the files I have not found a way to do through GE itself. This is setting the placemark style variations for normal versus highlighted. I’ve set the style so that normally there is no label but when you point to the placemark the label appears and the icon grows. You get this effect by setting up the style block like this:

<StyleMap id="msn_star">
    <Pair>
        <key>normal</key>
        <styleUrl>#sn_star</styleUrl>
    </Pair>
    <Pair>
        <key>highlight</key>
        <styleUrl>#sh_star</styleUrl>
    </Pair>
</StyleMap>
<Style id="sn_star">
    <IconStyle>
        <Icon>
            <href>http://maps.google.com/mapfiles/kml/shapes/star.png</href>
        </Icon>
    </IconStyle>
    <LabelStyle>
        <scale>0</scale>
    </LabelStyle>
</Style>
<Style id="sh_star">
    <IconStyle>
        <scale>1.2</scale>
        <Icon>
            <href>http://maps.google.com/mapfiles/kml/shapes/star.png</href>
        </Icon>
    </IconStyle>
</Style>

With no scale parameter specified for an IconStyle the default value is 1, and with no LabelStyle parameter the label scale defaults to 1.

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RSS for Traditional Web Pages

This method no longer works because Google removed the Note in Reader feature. See this new post for a better method that I wish I’d found before starting to use the method outline in this post.

I wanted to create an RSS feed for a section of my main web site so that regular visitors can find new or changed content easily. With blogs, and other types of sites based on a CMS, this feature is usually automatic. However my main pages are traditional manually created HTML so I would have to roll my own RSS generation. Reading up on RSS I learned it is fairly straight forward to do this, but it is labor intensive which means over the long haul there is no way I’d keep up with it.

Then I found a great article on how to use Google Reader along with Google’s FeedBurner service to make this task far less labor intensive. The easy to follow instructions are at the Digital Inspiration site in this article, Tutorial Create RSS Feeds for your Website.

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Aggregating and Filtering Web Sources

Trying to keep up with information on a topic via web sources is time consuming. While RSS feeds make it easier to find just the new information, there is still a lot of wasted time when feeds contain additional topics that don’t interest you. The solution is to filter feeds so that only the topic of interest is included. Some blogs allow you to filter the content by providing separate RSS feeds for each category of posts. Here’s how to get a feed of just the cartography category from this blog.

  1. Select the category you want from the dropdown list in the right sidebar.
    RSSfilter1 RSSfilter2
  2. Select the category feed from the RSS selector icon (Firefox on left, Internet Explorer on right).
    RSSfilter3F RSSfilter3IE
    RSSfilter4F RSSfilter4IE
  3. Finally, subscribe to the selected feed with your favorite feed reader, I use Google Reader. To follow other categories from the blog simply repeat these steps.

This works well for RSS sources that have category, tag or label specific RSS options, but many sites don’t have this feature. For sites without the feature you can use the filtering power of Yahoo! Pipes. Take a look at this Pipes filtered feed I created for a Blogger hosted Blog. Yahoo! Pipes provides an RSS feed of the output (as well as many other formats) that you can subscribe to in a feed reader.

Filtering feeds saves me time, but my feed reader still has too many items in the subscription list. Organizing my subscriptions by creating folders for topics in Google Reader helps reduce visual clutter and allows me to ignore less important topics when I’m busy. A more effective way of dealing with the long list is to aggregate multiple feeds with a Yahoo! Pipe. For example I have a single subscription to a pipe that combines 15 different sources about the people of, and places in, the Blackstone River Valley.

The Blackstone River Valley pipe aggregates these feeds:

If you know of other sources that belong in this pipe please leave a comment or send me an email. You may also like this aggregation of Blackstone Valley photos from five Flickr feeds.

One final note about Yahoo! Pipes, they don’t always seem to run completely when Goggle Reader first queries them (I think it’s a timeout issue). So I make it a habit to click on the pipes subscriptions occasionally even when there are no new items indicated. This sometimes finds updates to the pipe feed that were missed during previous polling by Google Reader.