Scientific Instruments
Scientific Instruments
 |
Hanna Instruments HI 98107 pHep pH Tester, with +/-0.1 Accuracy
List Price:  |
DescriptionpHep(r), the standard in pH measurement with 0.1 pH accuracy, has 2point calibration, large LCD, pull out replenishable junction and 700hour battery life. The pHep(r) pH tester features a casing that is morerugged and has been ergonomically enhanced to better fit your hand... |
Charles Marie De La Condamine - First Scientific Explorer of the Amazon
Charles Marie de la Condamine was a French explorer, physicist, geographer and mathematician born in Paris on January 28, 1701. His early interests in science led to his participation in the most important scientific mission of the times: in the early 1730’s there was a dispute as to whether the earth was wider around the equator or around the poles. Sir Isaac Newton argued the Earth was wider around the Equator; the French geographer Cassini argued otherwise.
The King of France and the French Royal Académie des Sciences sent two teams to find out the answer, one to Lapland and another to South America. La Condamine, as a young and promising member of the Académie des Sciences, became a part of the mission that was sent to South America by that body in 1735 to establish the length of a degree of the meridian in the vicinity of the Equator, so that it could be compared to the length of a meridian in Lapland and thus answer the question; this work also laid the foundation for the determination of the length of a meter.
The group also included Louis Godin des Odenais, Pierre Bouguer, and two officers of the Spanish marine, Antonio de Ulloa, and Jorge Juan y Santacilia. The latter two represented the Government of Spain on the journey and also made independent observations in the interior. They landed in Colombia and journeyed overland to Panama, then sailed to Ecuador. A local governor and scientist-mathematician, Pedro Vicente Maldonado, traveled through the rainforests with Condamine. They sailed up the Esmeraldas River and then went up the Andes Mountains, arriving in Quito on June 4, 1736.
Condamine’s mandate was to find out the shape of the earth by using a meridian and thus ascertaining the flattening of our globe toward the poles. Once in Ecuador he began his work, establishing a base line and making a reasonably accurate triangulation of the precipitous parts and the western sections of Ecuador. There he made one of his discoveries, that high mountains deflect the pendulum by their attraction.
Condamine, Godin and Bouguer were soon involved in disagreements. They finished their measurements by 1739, measuring the length of an arc of one degree at the Equator, but they got word that the Lapland expedition had already finished their work and had proven that the Earth is flattened at its poles. The three went their separate ways, and in 1743 Condamine began his return trip. The others chose to return to Europe by way of the better known route from Ecuador to Panama and by ship to Europe. Condamine decided to follow the longer yet more scientifically interesting path of crossing the Andes and entering the Amazon basin from the east, with a four-month raft voyage down the Amazon River.
The route Condamine chose began at the furthest traversable reaches of the Marañón River and went on through the treacherous pass at Pongo of Manseriche for the express purpose of seeing the pass. Traveling on a raft built by his guides, Condamine had quite a few close calls not only with his life but also the eight years of research and scientific instruments he was carrying back to France.
After passing through Pongo of Manseriche where the river narrowed from 1500 to 150 feet across, Condamine again almost lost his raft and work before emerging out of the mountains and onto the flat plain of the Amazon Basin. The raft arrived at a settlement on the river at Borja, where a priest provided him with a map of the area and accompanied him for the next portion of the voyage.
The expedition changed from rafts to two large canoes at Borja, each 44 feet long and 3 feet across. La Condamine must have felt safer in the new canoes with rowers paddling day and night, because he took up the task of measuring and mapping the river. In late July the group arrived at the spot where the large Ucayali River meets the Amazon and Condamine observed the Omaguas, a tribe first stumbled upon by the missionary Padre Fritz years before.
Several explorers of the New World in the preceding two centuries had brought back news of native poison-tipped arrows that brought speedy death by paralysis. These lethal arrows were generally Used for hunting animals, and they were occasionally used against the European explorers and soldiers. Natives called the toxic herb ourari, which became curare to the Europeans. Condamine collected samples of the curare and brought them back when he returned to France. He also discovered that curare was only poisonous when in contact with blood; it could be ingested without consequences, as many native foods included the same ingredient.
He also noted local rubber production techniques, calling the substance caoutchouc after the local term for weeping wood. Caoutchouc was named “rubber” in the 1770s after English scientist Joseph Priestley noticed that the substance could be used to erase pencil marks from paper. American inventor Charles Goodyear discovered vulcanization (a method of treating rubber to make it strong and elastic) in 1839 when he unintentionally dropped a combination of rubber and sulfur on a hot stove.
Condamine sent back some rolls of crude rubber in 1736, together with a report of the products manufactured from it by the people of the Amazon Valley. General scientific interest in the substance and its properties was revived. In 1791 the first commercial application of rubber kicked off when an English manufacturer, Samuel Peal, patented a method of waterproofing cloth by treating it with a solution of rubber in turpentine.
Natural rubber for commercial use is taken almost exclusively from Hevea brasiliensis, a tree native to South America, where it grows wild to a height of 34 meters (120 feet). Hevea only grows within a well-defined area of the tropics and subtropics where frost is never encountered.
As an explorer and physicist Condamine ranks very high, though because of his ambition and inclination to controversy he was a disagreeable character. The topographical work done by him or under his direction suffered from the comparative imperfections of the instruments in use at his time, but the results obtained were amazing. Not only in physiography and physical geography, but in other branches also his mission opened a new perspective to investigation. Father Fritz´s maps, the only available of the Amazon at the time, were corrected by Condamine and Condamine´s version closely resembles today´s Amazon.
He stayed in South America for ten years, and wrote excellent descriptions of his travels, notably the Journal d’un voyage fait par ordre du roi à l’équateur. He is considered the first explorer to visit the Amazon in search of knowledge and for scientific reasons. Previous visitors did so either in search of wealth (El Dorado) or souls (Jesuits).
About the Author
Secretário Estadual de Planejamento e Desenvolvimento Econômico, Amazonas, Brasil / Secretary for Planning and Economic Development, State of Amazonas, Brazil
www.dminev.com
Glass Blowing
 |
 CAVRO SCIENTIFIC INSTRUMENTS 728700 SYRINGE PUMP  US $129.99
|
 Hoefer Scientific Instruments Drygel Jr No SE540 Bio Rad 224 US $100.00
|
 HOEFER SCIENTIFIC INSTRUMENTS PS 1200 DC POWER SUPPLY US $196.00
|
| Powered by phpBay Pro |
|
Hanna Instruments HI 98107 pHep pH Tester, with +/-0.1 Accuracy
List Price: |
DescriptionpHep(r), the standard in pH measurement with 0.1 pH accuracy, has 2point calibration, large LCD, pull out replenishable junction and 700hour battery life. The pHep(r) pH tester features a casing that is morerugged and has been ergonomically enhanced to better fit your hand... |
 |
Hanna Instruments HI 98129 Waterproof pH/Conductivity/TDS Tester
List Price: |
DescriptionNo more switching between meters, the Combo Tester does it all! |
 |
Taylor 1479 Commercial Wireless Remote Digital Food Thermometer
List Price: |
DescriptionMEASURES INTERNAL FOOD TEMPERATURE WITHOUT HAVING TO OPEN OVEN DOORREMOTE ALERTS THE USER UP TO 200 FT FROM GRILL2 PRE-ALERT SIGNALS NOTIFY WHEN FOOD IS NEARING DESIRED TEMPDUAL FUNCTIONING THERMOMETERTIMERPROGRAMMABLE THERMOMETER TO PRESET OR CUSTOMIZE TEMPERATURE TARGETSBASE & REMOTE USE UNIQUE SIGNAL SOUNDS FOR THE THERMOMETER & TIME FOR EASE IN IDENTIFICATIONREMOTE HAS VOLUME CONTROL LANYARD STAND CLIP MAGNET & BACKLIGHTShipping Dimensions : 10... |
 |
Luster Leaf 1820 Rapitest Soil Moisture Meter
List Price: |
DescriptionInstamatic Moisture Meter Essential for Successful Growing This Rapitest Moisture meter is an invaluable aid in maintaining correct moisture levels. This accurate instrument will help you eliminate detrimental over or under watering! An instant reading is obtained from the tip of the probe into the root level... |
 |
Technology Alternatives 7021 Cell Sensor EMF Detection Meter
List Price: |
DescriptionYou might not know it, but certain areas in your home and work have powerful electro magnetic fields (EMFs) that can inflict severe damage to cellular DNA. Protect yourself against this invisible radiation by testing areas that you frequent with a gauss meter, a device that measures the strength of EMFs... |
 |
Texas Instruments Ti-83 Plus Graphing Calculator 10-Digit Lcd Ideal For The Algebra Classroom
List Price: |
DescriptionIncludes tools for finance. I/O port for communication with other TI products. |
 |
TEXAS INSTRUMENTS, TI 34 Multi-View Scntfc Calculator Bulk 34MV/BK (Catalog Category: Calculators Scientific)
Sale Price: $32.00 |
DescriptionSame functionality as the TI-34II Explorer plus display and feature enhancements. Designed with educators and ideal for middle school math. MultiView display shows fractions as they are written on paper... |
 |
Texas Instruments Ti-84 Plus Graphing Calculator 10-Digit Lcd Preloaded With Software
List Price: |
DescriptionI/O port for communication with other TI products. |
