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4 
Oct 10th
The best way to exhibit the screening influence to a class would be to suspend the coil after the method used by Dr. Hans and then to introduce different substances between the two while they are kept [[underlined]]continually[[/underlined]] at the same distance. 
The shock from the tertiary current with the foregoing arrangement was from the [[rupture?]] of the current and not from the induction at the beginning, for while the tertiary current was so powerful as scarcely to be reduced from the induction at rupture, the same current at forming contact could scarcely be perceived through the [[tongue?]]

Sent the current from the little machine through the long wire spool (4 inches) with helix No 1 on top, but found no result.

Sent the current from the little machine through two garded points in the bottom of a box to see if the cones of mercury would be produced as in the experiments of Davy, but no effect was perceived.

Arranged two lead syphons in mercury at the upper end so that a current of galvanism might pass up one and down the other--put the whole away with the shaker battery attached to note the effect on the morrow.

Oct 12th inspected the above, found that but little mercury had come over, but that the greater quantity was on the negative side, the same result was obtained with the arrangement with the large battery 
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                                                       5
Oct 10th
made some experiments on the light from the little machine. First whirled before the spark a disk with such velocity that figures on it could not be observed by ordinary light, these however were distinctly visible by the spark, showing that its duration was exceedingly small.

2nd the spark was received in the mirror of a whirling apparatus made for me by Mr. Saxton, and which revolves more than 30 thousand times in a second. In this it appeared elongated, which shows that although the duration was [[strikethrough]]not [[/strikethrough]] very short still it was not instantaneous. The appearance of objects by the spark was singular, all appeared in a kind of refractory motion which affected the senses very unpleasantly.

3rd the spectrum from the spark was received through a prism and presented a very singular appearance, the red part was small also the blue part, but the [[underlined]]yellow[[/underlined]] and [[underlined]]violet[[/underlined]] quite abundant.

This should be studied again under better circumstances, from a surface of mercury not surrounded with glass as in this case.

As an illustration of the power of the little machine, when in full action and excited by a large battery, I may mention that a labouring man, one of Mr. Clows servants [[strikethrough]]was [[/strikethrough]] being requested to take hold of the handles, immediately fell to the floor, his hands spasmodically grasping the handles.
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