194 New EleSrlc "Experiments. 



longer furniftied with fpikes, but is perfectly fmooth and 

 fomewhat rounded, and has been lengthened from fix to left 

 inches. 



By the conductor alone experiments were made. 



1. Refpe&ing the effect of electricity on the pulfe. Df« 

 Van Marurri thought he had reafon to conclude from his 

 former experiments, that electricity does not increafc the. 

 pulfe. But, as fome doubts arofe on this fubject, which 

 were fupported by a paper of Meffrs. Von Trooffwyk and 

 Deiman, he thought it might he of fome utility, in a fubject 

 ef fo much importance to medical electricity, to repeat the 

 experiments according to the method of thefe pb.iiofoph.ers-. 

 For this purpofc eleven pcrfons were felefted, and the expe- 

 riment was repeated four times on each, both with pofitive 

 and negative electricity. Theie pcrfons were placed in a. 

 foom which was at inch a diftance from the machine that 

 they could not hear the noife it made in turning ; they were 

 alio infulated, and their pulfe was felt when the machine 

 was in motion as well as when it was at reft (which laft cir- 

 cumftance was unknown to them), and the beats were told 

 Sy a good obferver by means of an excellent watch. In 

 tome fingle cafes a few beats more were obferved, but on the 

 whole there was no particular increafe of any confequence. 

 In general, however, there was great irregularity in the pulie 

 both during the time the pcrfons were electrified, and during 

 the time the machine was at reft. 



2. Reflecting the increafe of infenfible perfpiration during 

 the time the perfons were electrified. Dr. Van Marum em- 

 ployed for this purpofe a very fenfible balance, one fcale of 

 which was infulated by means of a filk cord. On this fcale 

 he placed a boy, eight years of age, connected with the con- 

 ductor, and brought the balance into equilibrium. He then 

 examined the lofs of 'weight fuflained in half an hour before 

 the boy was electrified, and found it amount to 280 grains ; 

 after which the machine was turned for half an hour, and 

 the lofs at the end of that time amounted to 295 grains. By 

 a fimilar experiment ou another occafion, the lofs of weight 

 before being electrified was 330, and after being expoied to 

 electricity only 310. A girl of feven year^loft, before being 



8^ electrified, 



