THE AMEPJCAN BEE JOUENAL AND GAZETTE. 



173 



tions, were to be looked for therefrom. But 

 when wo subject to careful scrutiny the ex- 

 periments and observations made in this regard, 

 we shall soon find that we can place only an 

 infinites! mally small portion of the increased 

 temperature of the hive to the credit of mus- 

 cular action. 



Reaumur appears to be the first who directed 

 his attention to the subject. In his '■'■ Mevioires 

 l)Oiir sorvir a PMstoire des iiisecfes,''' volume 5, 

 part 2, page 3G2, he says : "Bees generate heat 

 by the active jnotion of their wings and legs, as 

 we warm ourselves in cold weather by violent 

 exercise." But Reaumur failed to furnish the 

 proof of this assertion; and it is not easy to con- 

 ceive how he could have proved it. It need not 

 be denied that bees are able thus to raise the exist- 

 ting internal temperature of the hive one or two 

 degrees. But beyond this they cannot go, as will 

 be manifest from what will be hereinafter stated. 

 Besides, they are able to effect this for a very 

 brief period only, when suddenly exposed to 

 cold, or otherwise disturbed or annoyed. The 

 idicreased heat thus produced not only vanishes 

 again as soon as the muscular action from which 

 it arose ceases, but it diminishes already even 

 while that action is in continued operaiion, as 

 we shall presently see. 



The statements of Newport, who took up the 

 subject long after Reaumur's views were ex- 

 pressed, are much more precise. Still, they are 

 utterly untrustworthy, which fact is of the more 

 importance, since subseciuent inquirers rely 

 wholly on him, without having made any ob- 

 servations themselves. Newport says: "On 

 the 2d of January, 1806, at 7.30 in the morning, 

 with an external temperature of 17^^ F., the 

 thermomet/r indicated 30^ F. in the interior of 

 a hive, while the bees were wholly quiescent. 

 But when they were roused into activitj'- by 

 beating against the exterior of the hive, the in- 

 terior temperature rose to 70-' F. in sixteen 

 minutes. The 30'^ of F. scale corresponds with 

 0,30 of that of Reaumur, and 70^^ F. to 17,8° R." 

 It is hence manifest that Newport, when in- 

 serting his thermometer, did not introduce it in 

 the cluster of the bees, but placed outside thereof 

 in some vacant space, else he would have found 

 not 30fF. or 0,3" R., but at least 55^^ F., or 10° 

 R. Then,too,while he was pommelling the hive, 

 and exciting the bees, these gathered and 

 clustered around the thermometer, and thus 

 elevated the mercury to 70° F., or 17,8° R. 

 The increase of temperature consequent to the 

 pommelling was therefore not 17° R. and up- 

 wards, but actually, under the most favorable 

 supposition, (for the bees in their quiescent 

 state undoubtedly maintained more than 10° R. 

 of heat,) not more than 7° R. But even these 

 7° are not to be regarded as the effect or result 

 of muscular action. 



This is evident from the experiments made 

 on the elevation of temperature by muscular 

 action in the individual insect, as well as from 

 the increased temperature of the iudididual 

 muscle. Accurate experiments, touching the 

 former point, were made about twenty years 

 ago by Dutrochct, who first availed himself of 

 the aid of a thermo-electric apparatus in his in- 

 vestigations. 



By those means he found that the internal 

 temperature of a Maybug, so confined that it 

 could not move its legs, exceeded thit of the ex- 

 ternal atmosphere by from O,O0G° to 0,009.° But 

 when its legs were liberated, the internal tem- 

 perature of the struggling insect rose to 0,31°, 

 or about 0,22° or 0,25°, in conseciuence of mus- 

 cular exertion. This, however, was the greatest 

 amount of increased temperature produced in 

 the individual insect. When we compare there- 

 with the numerous experiments made by other 

 physiologists to generate heat in mammalia by 

 muscular action, and which never exhibit moi"e 

 than an increase of from 2° to 3° R. at most, 

 we are certainlj'^ justified in assuming that, in 

 the hive likewise, the increase of heat resulting 

 from muscular action cannot be greater. This 

 elevation of temperature, as has already been 

 remarked, can only be sustained for a short 

 time. The degree of heat prevailing in the 

 hive in the brooding season has hence no connec- 

 tion whatever with muscular action. 



"We infer this with the greatest probability 

 from the skillfully-deAised experiments of Dr. 

 Heidenhain on the development of heat in a 

 single muscle, pending increased action. After 

 a long course of most precise investigations, by 

 which it was first established that the heat man- 

 ifested during the irritation and contraction of 

 a muscle was not to be regarded as caused by the 

 increased fiow and circulation of the blood, but 

 really and truly, as generated in the muscle, he 

 deduces and announces the following law : 

 " With the increasing exhaustion of the muscle, 

 the development of heat always decreases more 

 rapidly than the action of the muscle 

 diuiinishes." 



In the active muscle the development of heat 

 proceeds only to a certain extent — small, in- 

 deed, under any circumstances, and never ex- 

 ceeding one degree of the thermometer; and 

 thence sinking again while the muscle is still in 

 action. Hence, if the heat decreases in the 

 muscle during continued action, it must, of 

 course, decrease also in the insect or animal it- 

 self. 



It would transcend the limits I have pre- 

 scribed to myself were I to give a full and de- 

 tailed account of the interesting experiments 

 made by Dr Heidenhain. Those who would 

 pursue the subject more at large can do so by 

 referring to his treatise "On Muscular Action." 

 For our purpose it suffices that, by the ascer- 

 tained and announced law, the assumption 

 that brooding heat is generated by energetic 

 muscular action, is refuted and altogether ex- 

 cluded. SCHONFELD. 



August 10, 1866. 



For the American Bee Journal. 



Egyptian Bee. 



Can any of the foreign writers of the Bee 

 Journal throw any light upon the compara- 

 tive fertility of the cpieen bees of this species ? 

 Also, upon their honey-storing capacity as com- 

 pared with the black and Italian varieties? 

 L. L. Faikchild. 



Rolling Praikie, Wis. 



