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

[Fred Schneider]

Guess I put foot in mouth up to ____________, Huh?

On Jun 25, 2008, at 1:35 PM, Gray, George wrote:

> 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
>>>
>>>
>>
>>
>
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