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

[Fred Schneider]

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
>>
>>
>
>