"Beaker". Online image.  Using the Lab Pro. 27 March 2003. http://www.ncsu.edu/sciencejunction/route/usetech/MBL/mbluse.html

"Balance". Online image.  Equipment Systems. 27 March 2003. http://www.e-quipmentsystems.com/balance_counter_scale.htm

"Thermometer". Online image.  Miami Museum of Science. 27 March 2003. http://www.miamisci.org/hurricane/thermometerread.html

"Thermometer".  Online image.  Kodak Health Imaging. 27 March 2003. http://www.kodak.com/global/en/health/productsByUse/medicalRadiography/filmImaging/technical/film.jhtml

"Thermy the thermometer".  Online image.  FSIS. 27 March 2003. 
http://www.fsis.usda.gov/oa/pubs/illpeaks.htm

"Ruler close up image".  Online image.  Macros Article. 27 March 2003. http://www.digicamhistory.com/Macros%20Article.html

"House drawing". Online image.  An Elegantly Simple World.  27 March 2003. http://www.engsw.com/PowerCADD/Simple/Simple3.html

"Ruler in centimeters".  Online image.  East Jessamine Middle School.  27 March 2003. http://www.jessamine.k12.ky.us/ejms/teched/measure_metric.htm

"Beaker with blue liquid".  Online image.  Science Venture.  27 March 2003. 
http://www.engr.uvic.ca/~sventure/

"Beaker tilted".  Online image.  About Indofine Chemical.  27 March 2003. http://www.indofinechemical.com/about.htm

"How to use a Thermometer". Online text.  Miami Museum of Science. 27 March 2003. http://www.miamisci.org/hurricane/thermometerread.html