ECOLOGY OF THE MURRAY ISLAND CORAL REEF. 



31 



EXPERIMENTS UPON TEMPERATURE. 



Table 4 presents the details and table 5 a summary of the observations 

 of the temperature of the water of the reef-flat and of the air close to the 

 surface of the water. 



Table 4. — Temperatures of the air over the reef and of the water on Line No. I across the 

 Southeastern reef of Maer Island, Great Barrier Reef, Sept. jo to Oct. 2J, 19IJ. 



Date 



1913 

 Sept. 30. 

 p. m. 



a"" 32" 



2 40 . 

 2 44 . 



2 56. 



3 08 . 

 3 14 



3 25 ■ 

 3 36. 

 3 44 ■ 

 3 SO . 



5 00 



5 06 



Oct. 3.,. 



a. m. 



6'' 10' 

 6 17 

 6 22 



6 43 



7 00 



Oct. 4... 



a. m. 



6'' 37" 



7 35 

 Oct. 9 . . 



p. m. 



iz*" 45" 



Oct. i;.. 



p. m. 



4 22 

 Oct. 16.. 



p. m. 



2*' 48" 



2 S^ 



3 05 



4 34 

 4 37 



Condition of tide, wind, etc. 



Stiff southeast breeze 15 to 20 



miles per hour. 

 Water receding, near low water 



of new moon spring tide. 



Do 



...Do 



...Do 



...Do 



.... Do 



.... Do 



Time of lowest water 



Tide coming in, water rising.. 

 .... Do 



Do. 

 Do. 



Sun just risen, low tide, southeast 

 breeze of about r; miles per hour 

 blowing all night. Intermediate 

 tide, neither neap nor spring. 



Do 



...Do 



Tide about lowest 



Tide beginning to rise 



Tide rising 



Low tide. A southeast breeze of 

 about 15 miles per hour blow- 

 ing all night. 



Low tide, about the lowest 



Tide coming in 



Southeast breeze about 8 miles per 

 hour. Neap tide came Oct. 7. 



Low tide 



Spring tide of full moon. Gentle 

 east breeze. 



Tide beginning to rise 



Tide rising 



Flat calm. Water receding, low 

 at about 4 p. m. This tide 

 was fully as low as the spring 

 tide of yesterday. 



Tide receding 



...Do 



Tide about low 



Tide coming in 



. ...Do 



Distance 

 from the 



shore, meas 

 ured from 



mean high- 

 tide line. 



{eft. 



200 



400 

 600 

 800 

 1,000 

 1,200 

 1 ,400 

 1 ,600 

 1,800 

 1 ,800 in 

 breakers at 

 outer edge 

 of reef. 

 200 

 400 



200 



400 



600 



1 ,200 



1 ,860 in 



breakers. 



400 

 800 



I ,7CKD 



100 



lOO 



850 



1,620 



400 



100 



Depth of 

 water. 



inches. 

 4 



■5 



.5 



-25 



■25 



■5 



■5 



■5 



4 



4-5 

 7 



9 25 

 24 =^ 



4.7.1; 

 12. 5 



4.5 = 



6 = 

 18 = 

 12 = 



5-5 

 6 = 



Air. 



27.5 



27 



26.5 



26 



26 



26.25 



26.2 



26 



25-5 



25-5 



265 

 26.2 



25 

 25 

 24.5 



25 



25 



25 

 24.4 



27,8 



26 4 



26. 2 



26.8 

 26.4 

 26.2 

 26.4 

 26 7 



Temperature. 



Water. 



31 



30 



29 



28.5 



28.5 



28.5 



28 



28 



27-5 



25-5 



27 

 27 5 



22 



22.5 



23 



23 



25 



24.4 



23.1 



34 5 



25.6 



30 4 



334 



29 



28.8 



29.2 



30.8 



Difference. Water 

 warmer than air -f 

 cooler than air — . 



C 



3-5 + 



+ 

 5 + 

 5 + 

 5 + 

 25 + 

 8 4- 

 + 

 + 



0.5 + 

 1-3 + 



3 



2-5 



15 



2 

 o 



2.6 - 

 13 - 



6.7 + 



0.8 - 

 4.2 -f- 



6.6 4- 



2.6 + 



2.6 -f 



2.8 -f 



41 + 



