142 ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 47 



animal cages to keep various creatures in captivity during scientific 

 investigations. 



TERMITE-FREE BUILDINGS IN THE TROPICS 



Is is possible to build comfortable, well-ventilated houses of lum- 

 ber and not have a termite hazard ? The answer is "Yes." However, 

 few architects go to the trouble of getting the necessary information. 



We have 57 known species of termites in Panama and the Canal 

 Zone. Of these, 45 species occur on Barro Colorado Island. Two of 

 the most destructive in the world occur here, one of which is known 

 to eat through the lead sheathing of electrical cables. The rapidity 

 of destruction by some of the species is incredible. Some even work 

 in living trees, and we have records of fruit orchards destroyed by 

 them. 



And yet on Barro Colorado Island we have buildings where Ave let 

 the termites do whatever they wanted to do — eat up the building 

 overnight if they could — and yet these buildings are in excellent 

 shape. 



In 1926 we built a test house at the end of Drayton Trail, 16 feet 

 square and 10 feet high, set on wooden posts extending 3 feet into 

 the ground. The timber used was pressure treated with coal-tar 

 creosote and with zinc chloride. The wallboard is treated with chro- 

 mated zinc chloride. In the May 1947 number of Wood Preserving 

 News Dr. Thomas E. Snyder, senior entomologist of the Bureau of 

 Entomology and Plant Quarantine, published all details and results 

 of his inspection in February of this year, showing no damage any- 

 where due to termites, and yet termites tried to get a hold. The build- 

 ing is in excellent condition after 21 years. It is true that pressure 

 treatment increases the original cost of the timbers, but it is cheap in- 

 surance. A building of untreated timbers would have been destroyed 

 in less than a year. 



At the end of the Pearson Trail we have the Fuertes House, built 

 in February 1931, 16 years ago. It is set on nine posts; hence there 

 is good ventilation under the house. With the exception of the shin- 

 gles, which are of red cedar (and need replacement), all the wood and 

 timbers, including posts, were treated with zinc-meta-arsenite. The 

 tables and chairs are also so treated. There is no damage anywhere to 

 the treated wood. The wallboard also was zinc-meta-arsenite treated. 

 It likewise is free of any termite damage. Test stakes of untreated 

 wood half-buried in the ground near the building were destroyed 

 within 8 months. 



Furthermore, this zinc-meta-arsenite treated building is free of 

 cockroaches. No steps are taken to keep termites out of the building, 

 and no termite shields are used — ^hence, termites have absolute free- 



