January 7, 1898.] 



SCIENCE. 



Experiment 5. A potted plant of Cala- 

 dium was placed with the leaf within 20 cm., 

 with a small piece of sheet lead so placed 

 between it and the bulb as to intercept a 

 portion of the rays. The exposure contin- 

 ued for five hours. At the close of the ex- 

 periment, and subsequently, no change 

 could be observed. 



Experiment 6. On June 8th a large num- 

 ber of seedlings which had been started 

 previously in soil contained in wooden trays 

 were placed in front of the light and ex- 

 posed for several days. The seedlings used 

 were those of corn, oats, wheat, radish, sun- 

 flower, soja bean, white lupine, cucumber, 

 vetch, pea, German millet and cotton. 

 There were several duplicate sets of the 

 seedlings for this experiment ; one lot was 

 planted June 1st and the other June 5th, to 

 provide seedlings in difierent stages of 

 growth. From some which were just germi- 

 nating they ranged in size to those which 

 Avere 10 cm. high. The following gives the 

 facts concerning the condition of the seed- 

 lings on June 8th, at the time of starting 

 the experiment : 



LOT 1. PLANTED JUNE 1ST. 

 NAME OF PLANT. CONDITION JUNE 8TH. 



Sunflower 5 — 8 cm. 



"Wheat 8—10 cm. 



German millet 3 cm. 



Nonpareil bean just coming through the soil. 



Soja bean 5 cm. 



Cotton just coming through the soil. 



Oats 8— 10 cm. 



Corn 5 — 8 cm. 



Vetch 5—8 " 



Pea 2—5 " 



Cucumber 2 — 4 " 



LOT 2. PLANTED JUNE 5TH. 

 NAME OF PLANT. CONDITION JUNE 5TH. 



Cotton germinating. 



Wheat germinated. 



Sunflower nearly up. 



German millet germinated. 



The boxes containing the seedlings were 

 so arranged that some of the seedlings were 



very near the bulb, while others were at 

 varying distances, to the front, and right 

 and left, so that if anj' distinct influence 

 was manifested the extent of the field of 

 this influence could be easily determined, 

 and its degree, to some extent, be measured 

 by the effect on the plants at varying dis- 

 tances. The field was explored with a 

 fluoroscope to be certain that the i-ays 

 reached all the plants which were placed in 

 front of a line a few centimetres in advance 

 of the bulb. A check lot of the seedlings 

 was placed behind the instrument in the 

 dark room in which the experiments were 

 being conducted, so that they might grow 

 under exactly the same conditions, except 

 that they would not be under the influence 

 of the Rontgen rays. 



The experiment was started at 11 a. m., 

 June 8th. The run was continued until 

 11 p. m., but since the interrupter in con- 

 nection with the coil did not work satisfac- 

 torily the circuit was permanentlj' broken 

 at intervals. During this period the cur- 

 rent was on about one-half the time. The 

 following day, June 9th, the interrupter 

 continued to work unsatisfactorily, and 

 finally broke down at 5 p. m., the current 

 having been turned on at 8 a. m. During 

 the day of June 9th the instrument was 

 running about oue-fourth of the time. The 

 interrupter was repaired and the current 

 was started again at 10:20 a. m., the follow- 

 ing morning, June 10th, and a continuous 

 run was made up to 11 p. m., June 11th, 

 the run was continuous from 8 a. m. until 

 11 p. m., and on June 12th, Saturday, from 

 8 a. m. to 4:30 p. m., when this experiment 

 was discontinued. 



During all of this time the plants be- 

 haved exactly as one would expect them to 

 in an ordinary dark room. Those which 

 had not come above the soil before they 

 were placed under the influence of the 

 Eontgen rays were entirely etiolated, while 

 .the new growth of shoots and leaves on 



