202 



SCIENCE 



[Vol. LVI, No. 1442 



nascent hydrogen obtained in this way is very 

 active in penetrating the palladium. At 0° C, 

 the thermoelectric power of the palladium, after 

 being exposed to nascent hydrogen, was in one 

 case only 28 per cent, of the value for the gas 

 free metal. The process of filling with hydro- 

 gen by the electrolytic method and then re- 

 moving the gas by heating in vacuo to abouf 

 700° C. was repeated several times and each 

 time the thei-moelectrie power was lowered by 

 about the same amount as a result of the ab- 

 sorption of the gas and restored to the original 

 gas free value upon removal of the hydrogen. 



To obtain the largest effects it was necessary 

 to use the palladium soon after it had been ex- 

 posed to the hydrogen as the gas slowly dif- 

 fused away from the metal over a period of 

 several days. Also if the region containing the 

 temperature gradient of the gas filled strip 

 -were heated during a determination of thermo 

 e m f , the result was a removal of the hydrogen 

 and a restoration to the original gas free value 

 of thermoelectric power. During a determina- 

 tion of thermo e m f the conduction of heat 

 from the hot junction along the palladium 

 strip caused the evolution of some of the gas 

 and for the higher temperatures of the hot 

 junction the thermoelectric power approached 

 that for the gas free metal. 



These results show that a monometallic cir- 

 cuit consisting of gas free and gas filled palla- 

 dium will give rise to a thermo e m f when 

 the junctions are at different temperatures. 

 Since palladium is negative at the cold junc- 

 tion of a palladium-platinum couple, and since 

 the absorption of hydrogen causes a reduction 

 in thermoelectric power, it follows that gas 

 filled palladium is positive to the gas free metal 

 at the cold junction. Data obtained for one 

 case in which the palladium was electrolytically 

 filled give the value of the thermo e m f in 

 such a monometallic circuit as: E = 0.126 — 

 0.00023e-, where 8 is the temperature of the hot 

 junction, the cold junction being to 0°C. The 

 constants will depend upon how completely the 

 palladium is filled with hydrogen. 



According to the electron theory of thermo- 

 electricity the thermoelectric power (e) 

 of a couple is given by the expression: 



e = £■ log— ^, where K is a constant, n^ and w^ 



are the effective electron densities in the two 

 materials forming the circuit. When n^ is 

 larger than rif, the current flows from material 

 a to material & at the cold junction. The effect 

 of absorbed hydrogen, then, is to increase the 

 effective electron density in palladium. 



E. M. Holmes 

 Department op Physics, 

 Cornell University, 

 June 10, 1922 



THE EFFECT OF SPERM BOILED IN OXA- 



LATED SEA-WATER IN INITIATING 



DEVELOPMENT 



In connection with certain experiments (the 

 results of which have not yet been published) 

 that were made in an attempt to analyze the 

 role of calcium in the fertilization of the egg 

 of Nereis, the following results were obtained: 

 (1) Nereis spei-m that have been treated with 

 oxalated sea-water are capable of fertilizing 

 normal Nereis eggs; (2) Nereis eggs treated 

 with oxalated sea-water are capable of fertiliza- 

 tion with normal Nereis sperm; (3) Eggs of 

 Nereis are capable of fertilization in oxalated 

 sea-water. Such eggs form jelly, maturate, 

 cleave and give rise to swimming larvse in the 

 oxalated sea-water. These larva3 show a vary- 

 ing per cent, of abnormalities; (4) Uninsem- 

 inated Nereis eggs treated with oxalated sea- 

 water (0.5 per cent, and above of sodium or 

 potassium oxalate in sea- water) form swim- 

 ming larvaa which show differentiation without 

 cleavage; (5) Sperm of Nereis boiled in 0.1 

 per cent, to 0.25 per cent, sodium or potassium 

 oxalate in sea-water are capable of initiating 

 development in the egg of Nereis. This last 

 result may be briefly considered. 



Uninseminated eggs of Nereis obtained by 

 cutting a dry female are exposed to each of 

 three lx)iled sperm suspensions. These Ijoiled 

 sperm suspensions are made up as follows : 

 one drop of dry sperm in 5 cc of sea-water; 

 one drop of dry sperm in 5 cc of 0.53 M NaCl; 

 and one drop of dry spei-m in 5 ce of 0.1 to 

 0.25 per cent, sodium or potassium oxalate in 

 sea-water. In each case the drop of spenn is 

 carefully placed in the bottom of a test tube 

 and the solution added. The test tube is then 

 quickly brought to the boiling point over a 

 flame and the suspension is kept at the boiling 



