[PRCo] Re: PennDOT historical maps (was: West Penn Street Car??)

[Gray, George]

Plane.

From: Plane Table Mapping by Milton Denny, PLS, August 29, 2000 at
www.pobonline.com 
Plane table mapping is a subject that has received minimum attention
over the years, but it played a very important role in the history of
surveying. The plane table dates to approximately the beginning of the
17th century. Some of the first references to the plane table are found
in early survey textbooks. The early plane table was a mapping tool, as
opposed to the compass and chain that was a boundary tool. The early
plane table dealt mainly with planimetric features and not with vertical
elevation. The use and development of the plane table has gone through
four distinct changes since about 1600.

-----Original Message-----
From: pittsburgh-railways-bounce at lists.dementia.org
[mailto:pittsburgh-railways-bounce at lists.dementia.org] On Behalf Of Fred
Schneider
Sent: Wednesday, June 25, 2008 1:31 PM
To: pittsburgh-railways at dementia.org
Subject: [PRCo] Re: PennDOT historical maps (was: West Penn Street
Car??)

plain not plane    fws

On Jun 25, 2008, at 12:06 PM, Fred Schneider wrote:

> But remember, Don, that the USGS maps are all plane table mapping
> technology.  The aerial surveys of today are a whole lot more
> accurate in some ways.
>
> On Jun 25, 2008, at 9:52 AM, Donald Galt wrote:
>
>> On 25 Jun 2008 at 8:31, Edward H. Lybarger wrote:
>>
>>> There was a lot of sloppy mapmaking in those days.
>>> But the fact that it was
>>> done at all with the available tools is
>>> remarkable.
>>
>> Yet, the best mapmaking of the early XX century is stunning, like
>> any work that
>> an artist takes seriously. By and large, USGS topos at 1:62500 and
>> 1:125000 are
>> exquisitely engraved and highly accurate (surveying may have been
>> harder than
>> it is nowadays, but was not to be sniffed at). They can easily
>> stand being
>> blown up to double size, thereby yielding even greater detail.
>>
>> And that's just the US. The best of European government mapping of
>> that era is
>> if anything even better.
>>
>> Of course, GIGO as you say. It's not that unusual with slightly
>> earlier 1:62500
>> maps to find railways crossing contour lines back and forth like
>> roller
>> coasters.
>>
>> That rendering of the Charleroi interurban is an example of
>> careless freehand -
>> quite possibly taking a smaller-scale map as its source. A similar
>> example is
>> on the Cambria County map, where the Southern Cambria line across
>> country to
>> Ebensburg and Nanty Glo appears drawn in two or three strokes.
>>
>> Don G
>>
>>
>
>