C 363 ] 
how manageable the magnetic Virtue is in refpedl to 
its Dire&ion ; and how defective moft of the Hypo* 
thefes are, which have been raifed to account for the 
Phenomena, of the Loadftone. 
Tour obedient humble Servant , 
Gowin Knight. 
IV. An Account of feme very curious Wafps 
Nefts made of Clay in Peniil vania ; by Mr. 
John Bartram : Communicated by Mr. Peter 
Collinfon, F. R. S. 
Read April 25. TR. ohn Bartram , a diligent Ob* 
y ferver of natural Productions, fent 
me, from Fenjilvania , two Sorts of curious Wafps 
Nells made with Clay, which are commonly built 
againft the Timber under the Roofs of Houfes and 
Pales, to fhelter them from the Weather. They feed 
as the Bees, on Flowers; but whether they Bing like 
them I do not yet know. 
The plain Clay-Neft is fabricated by a fmall black 
Wafp, of the fame Species of that in Tab. III. 
Fig. 1. but lefs, that has a Speck or Stripe of Yel- 
low in its Tail ; and the Cells are made four or five 
together, joining Side by Side to each other. But 
the Clay-Nefts that are fo elegantly wrought are 
built by a purplifh black Wafp, fuch as is figured. 
Tab. 
