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 *Scan the following sections for any hints that might be relevant.
 * Call the supplier or manufacturer, tell them that we have a problem with the new equipment, and try to get troubleshooting help over the phone. Why not do this first? Telephone help is fine, but if the call merely results in arrangements for a replacement requiring delays of days or even weeks, then a few minutes or even hours of preliminary troubleshooting may be justified. The supplier may suggest that returning the equipment for their evaluation is more practical than telephone troubleshooting, because that is easier for them. If so, remind the supplier that they claimed to be in business to serve you, not vice versa.

If troubleshooting equipment or an experiment that formerly worked fine:

 * 1) Go back to previous data and identify when the problem began, then list all changes to the system that occurred at about that time. The cause of the problem is probably in the list.
 * 2) Run a benchmark check: try to replicate a measurement or result that you have previously obtained and that you are reasonably certain is valid. If it replicates OK, then how does this sample differ from the problem sample? If it does not replicate, then what may have changed since the original correct measurement? If this test is inconclusive, then a second replication test may be worthwhile, using a sample with quite different characteristics.
 * 3) Consider the following frequent sources of equipment problems: incorrectly remembered measurement procedures, blown fuse or circuit breaker, part failure, a corroded connection, supply voltage variations, and temperature-sensitive components or equipment response. The first three usually cause a complete failure, and the others often cause intermittent problems.
 * 4) If none of the above help, then possibly you have an uncontrolled variable that is influencing the results. Methods for dealing with such variables are described later in this chapter.

Search is fundamental to scientific method. Search procedures can be used for finding objects and for troubleshooting problems. More generally, search is exploration-based research. Search procedures can provide a practical way of dealing with the complexity of nature. They can help one to focus efforts or scientific questions, in order to reduce them to a tractable size (Killeffer, 1969).

Most scientists are aware of most search procedures. Nevertheless, we often succumb to the pitfall of choosing the first search procedure that comes to mind, rather than deliberately selecting the most appropriate procedure. The following list of search considerations and techniques is largely based on a compilation by Wilson [1952]: “Kilimanjaro is a snow covered mountain 19,710 feet high, and is said to be the highest mountain in Africa. Its western summit is called by the Masai ‘Ngaje Ngai,’ the House of God. Close to the western summit there is the dried and frozen carcass of a leopard. No one has explained what the leopard was seeking at that altitude.” [Hemingway, 1940]
 * Characterize the object of the search. List the characteristics of the search object, and for each characteristic consider whether or not the object differs from its surroundings.

Characterizing the search object has been the nemesis of attempts to find the ‘missing’ mass of the universe. If, as many cosmologists previously expected, the universe is to collapse someday into an infinitely small point like that which began the