FEEDING HUMMING BIRDS SHERMAN. 465 



average of 462 grains per day. This for the six birds frequently 

 counted as present confirmed the first rough estimate of a teaspoon- 

 ful of sugar daily for each bird. 



Another method of estimating the amount eaten was devised. 

 On several days the sugar and the water were carefully measured 

 and weighed, then weighed and measured again, after which the 

 sirup resulting from their combination was also measured and 

 weighed, until I felt confident that in a dram of the thinnest sirup 

 served there were 40 grains of sugar, or two-thirds of a gram to 

 every drop. But the sirup usually used was considerably richer 

 than this, easily containing a grain of sugar in every drop; but it 

 seems best in giving the estimates to keep them to the weakest gi'ade 

 of sirup ever served. 



In making the test a dram of sirup was measured in a glass grad- 

 uate, and bottle No. 4 was filled. This was always done in the morn- 

 ing, when the bottle had been emptied by ants. A waiting humming 

 bird came and took her breakfast, after which the residue of sirup 

 was poured back into the graduate, the bottle being thoroughly 

 drained. Possibly a drop still adhered to the bottle, but the number 

 of minims now in the graduate subtracted from 60 must have given 

 very nearly the amoimt drunk by the humming bird. In two sum- 

 mers a number of these tests were made. A bird took for her break- 

 fast from 8 to 20 minims, the average being 15. Using the low 

 estimate of two-thirds of a grain of sugar to each drop, the average 

 breakfast held 10 grains of sugar. A better comprehension of the 

 size of that meal may be gained by remembering that two large 

 navy beans or one medium-sized lima bean also weigh 10 grains. 

 Breakfast and supper were the rubythroats' heaviest meals, but there 

 were many luncheons between them. By reckoning eight to nine such 

 meals dailj'- (and beyond doubt there were that number), Ave reach 

 again the first estimate of TO to 90 gi-ains of sugar as the daily ration. 

 About this amount of sugar is held by a common teaspoon when level 

 full ; such a spoon will hold from 110 to 120 minims of water, whereas 

 one of those heirlooms, a grandmother's teaspoon, is the measure of 

 the standard teaspoonful of 60 minims. Eeferring, then, to the 

 standard measure, the bird would be said to eat two teaspoonfuls of 

 sugar daily. An ordinary cube of loaf sugar contains the equivalent 

 of this amount. 



Reflecting upon the bulk consumed by so small a creature, one 

 naturally desires to know the weight of a humming bird. A little 

 boy brought to us the body of a male that had been shut into a 

 machine shed, where its death may have resulted from starvation. 

 Its weight was 33 grains. Naturalists in early days were vexed by 

 the same question, as is shown by a quotation given by Mr. Eidgway 

 44863°— SM 1913 30 



