You've tested your idea and you know it works. You've kept complete and accurate records of your conception and experimentation. Now what? Under the conditions of the patent law, you must establish that your idea is novel and not obvious. An invention cannot be patented if before you made your invention:

			The invention was known or used by others in this country.
			The invention was previously patented in this or another country.
			The invention was described in a printed publication anywhere in the world.
			There were publications, patents or uses that make your invention obvious.

If you wish to establish whether your invention is indeed new and unobvious, you will have to expand your preliminary search for existing patents and literature related to your invention. The literature search can be carried out by usual means available to scientists and engineers.
You can conduct such a search in your college library in a manner that any researcher would conduct a thorough literature search. For example, in the chemical area, searching the Chemical Abstracts will reveal technical publications and patents, which relate to your invention. A search of only the U.S. patents can be made in the Public Search Facility, Madison East, 1st Floor, 600 Dulaney Street, Alexandria, Virginia.
You can also do searches on the World Wide Web. Two major sites that allow you to search patents filed since the mid-1970's are:

			The U.S. Patent and Trademark Office http://www.uspto.gov - there is no charge to search on this site.
			Delphion http://www.delphion.com/ - formerly the IBM Intellectual Property network, this site charges a subscription fee.

If in a search you have identified U.S. patents that are relevant to your invention, for a nominal fee you may obtain copies of such patents from the U.S. Patent and Trademark Office at the above given address. You may also make copies of U.S. patents from collections of microfilms maintained by any of the Patent & Trademark Depository Libraries located throughout the U.S., where collections of patents can be accessed by computer and then studied. A list of Patent & Trademark Depository Libraries is available at the U.S. Patent and Trademark Office web site. (If you have a problem with this link, go to www.uspto.gov - look for "Libraries-PDTLs".)

Many inventors hire professionals to conduct patent searches and to analyze the results. If you decide to get help, be sure to hire a practitioner who is registered to pre-pare and prosecute patent applications. You can consult the Yellow Pages of your phone book; the Patent and Trademark Office also maintains a list of registered patent attorneys and agents. The list is also available on the U.S. Patent & Trademark Office web site.