412 Mr. de Luc on 
decreafing fteps, begins foon to Jhorten , at the fame time that its 
fubftance continues to imbibe water ; being thus the Jhorteft , 
when it cannot receive any more water in its pores. That excefs 
of the hygrofcopic phenomenon of threads cannot but throw a 
full light on the nature of thofe hygrofcopes. 
pi. I am now going to aflemble, in two tables, the com- 
parative marches of all the threads , and of all the Jlips , which 
I have hitherto fubmitted to that regular courfe of experi- 
ments, laying afide many more of each clafs, the marches of 
which I only know from common obfervations. The next 
table fhall contain the experiments on threads-, in the num- 
ber of which are two thin natural bodies, which in that refpeft 
are fimilar to the hair ; one, an animal fubftance, is a very 
thin porcupine quill ; the other, a vegetable, is a thin ftem of 
gramen. 
: v' ! 1 * ' ■ n . w . bp r ' P' : 
Table 
