Endeavor history

Roofs are a basic element of shelter from inclement weather. Natural or hewn caves, including those of snow or ice, ate early evidence of human endeavors for protection from the cold, wind, rain, and sun. Nomadic people, before the benefits of agriculture had been discovered and housing schemes developed, depended on the availabiUty of natural materials to constmct shelters. Portable shelters, eg, tents, probably appeared early in history. Later, more permanent stmctures were developed from stone and brick. SaUent features depended strongly on the avadabihty of natural materials. The Babylonians used mud to form bricks and tiles that could be bonded with mortars or natural bitumen. Ancient buildings in Egypt were characterized by massive walls of stone and closely spaced columns that carried stone lintels to support a flat roof, often made of stone slabs. 

The structural modification of natural products is useful in several ways. The known pharmacology of bisindole alkaloids is enriched by the diversity of chemical structures that are made available by structure modification and total synthesis. These molecules have served as biochemical probes in several areas of biology, especially in those of microtubule assembly and drug resistance. The most elusive prize, however, has remained the discovery of new compounds with clinical activity. In recent years several compounds have been evaluated in clinical trials, but vinblastine and vincristine remain the only bisindole alkaloids approved for the treatment of cancer in the United States. These compounds are joined by vindesine in Europe, and at least two new derivatives are the subject of ongoing clinical trials. Considering the breadth of chemical research in this area, the overall yield as measured by new compounds with clinical activity has been relatively low, but this observation is not unique in history of analog development in cancer research. Nevertheless, the search continues, and this chapter details the chemical endeavors to discover a new bisindole alkaloid with clinical activity. 

But then the duke sent Leibniz away on a diplomatic mission. By the time the philosopher returned, he had turned to other endeavors and lost interest in his phosphorus project. At this point Brandt disappears from history, and all that is known about the rest of his life is that he lived a fairly long time. Brandt might have still been alive in 1710, when he would have been in his eighties, according to Leibniz. Leibniz remarked that at least he had not heard of Brandt s death. 

The present volume was in the planning stage at the time of the death of Professor Melville L. Wolffom, but it is one of the few volumes in the history of this Series not to have received his editorial attention. His influence always reflected the precision and accuracy that he applied in his own writings, and the present Editors will endeavor to meet these criteria. 

Veblens comment illustrates only one of several parallels between science and history, though perhaps the most important. The search for truth and understanding, whether it be in science, in history, or in any other human endeavor, is a never-ending activity. To assume, even unconsciously, that we have reached some kind of finality is to betray the enterprise altogether. Those who attempt to eschew interpretation and write history as it really was are doomed to failure and disillusionment. Historical truth is no less tentative than scientific truth. 

The discovery that shows, beyond all others, that Hipparchus possessed one of the masterminds of all time was the detection of that remarkable celestial movement known as the precession of the equinoxes. The inquiry that led to this discovery involved a most profound investigation, especially when it is remembered that in the days of Hipparchus, the means of (5) observation of the heavenly bodies were only of the rudest description, and the available observations of earlier dates were extremely scanty. We can but look with astonishment on the genius of the man who, in spite of such difficulties, was able to detect such a phenomenon as the precession, and to exhibit its actual magnitude. I shall endeavor to explain the nature of this singular celestial movement, for it may be said to offer the first instance in the (10) history of science in which we find that combination of accurate observation with skillful interpretation, of which, in the subsequent development of astronomy, we have so many splendid examples. 

JL HE WORLD IS BUILT FROM SILICON-BASED polymers. Silicate materials in many shapes or forms account for more than 90% of the land mass. Technologies associated with these materials have been developed through recorded history, but the science underlying these materials is, relatively, still in its infancy. The first systematic study of silicon chemistry was carried out in the first two decades of this century. The first useful synthetic or-ganosilicon polymers, the polysiloxanes, were developed in the late 1930s, and a new industry based on these synthetic polymers was bom in the early 1940s. This industry has grown rapidly worldwide to the point that it is now a multi-billion-dollar endeavor. 

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