Written by NLR, Inc

About NLR Asrepparttar leading provider of comprehensive universal waste management services, Northeast Lamp Recycling (NLR) serves commercial, industrial and residential customers throughout New England, New York, New Jersey andrepparttar 110098 United States. Headquartered in East Windsor, Connecticut, our primary focus is to significantly reduce environmental mercury-contamination associated withrepparttar 110099 improper disposal and

Maps of Time and Tide.

Written by Seamus Dolly

Maps, for centuries have beenrepparttar business of cartographers with mariners traditionally being able to make their own, in uncharted waters. Yes,repparttar 110097 expression is still used in various contexts. I suppose that givenrepparttar 110098 nature of open seas, one had little option but to find their own way. When a courier pigeon wasrepparttar 110099 quickest communication device for help, an understanding of mapping was essential to evade Davy’s Locker.

Land based cartographers were respected for their diligence and discipline that their trade required. Bench marking is another expression still used where a reference point is needed. It came from land surveyors and map makers. Particular heights above sea level were transferred inland, further and further, to give mappers some idea, as it couldn’t be guessed with any accuracy otherwise. Indeed, twenty years ago, these benchmarks were heavily relied upon, whererepparttar 110100 presence of any other reference, was absent.

Now though, local authorities and surveyors use GPS or Global Positioning System. Even local civil engineers have access to this technology, and use it for projects such as small housing and commercial estates to anything bigger. Sorepparttar 110101 traditional benchmarking system, which was little more than a ground anchored “pad” of stone or concrete, has already been replaced by something that can view an area in a larger relative context, a satellite.

A satellites’ height above ground, or sea if you like, affords it a referencing advantage. There is no longer a need to physically walk torepparttar 110102 sea (sea level), and determine levels, thereafter. The sea is water, to some degree, and whilerepparttar 110103 earth is round also to some degree, water was “the great leveller”. It has also been replaced by various liquids that are more visible, and have less tendency to obscurerepparttar 110104 inside of levelling chambers. Some have anti-freezing properties. You see, any accuracy relied onrepparttar 110105 visual clarity ofrepparttar 110106 waters position within its’ clear container, and of courserepparttar 110107 mappers understanding of parallax error. Parallax error is mainly a human one, where something is not viewed, correctly, or in cases like this, not viewed at 90 degrees exactly.

A photogrammetrist is a different version of a cartographer, and though their purpose isrepparttar 110108 same, their approach is different. They use aeroplanes in place of mountain boots, and indeed helicopters, which speed uprepparttar 110109 process. Indeed, some areas can only be practically mapped this way.

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