EXTRACTS FOREIGN AND DOMESTIC. 149 



land rhomboids, &c. ; some five or six inches and more on llie sides • 

 and thus affording a very interesting evidence of the various de- 

 grees of temperature at the time those birds lived and walked over 

 the earth, at the time those tracks were made that were alluded to 

 'yesterday. This fine old meteorological record of the weather in 

 :;hose days, (being so much more ancient and interestino- than the 

 •ecords of ancient Egypt,) were thus stereotyped on the spot, and 

 ;ealed up, to be opened and exhibited to us thousands of ages 

 1 norwards, as a true record of that part of the earth's history. He 

 ia.l some difl^culty in regard to the large size of the rhombs and 

 nangles he found in the sandstone ; but after much examination 

 le found in 1841, after a frost, specimens of similar triangles and 

 Ihombs, lormed by the crystalization of the water during the 

 liight ; some of the triangles were twelve inches in length ; some of 

 he rhombs were eighteen inches long; and what was remarkable, 

 hcse crystals of ice had pressed upon the thin crust of mud beneath 

 ml made indentations similar precisely to the evidences of conge- 

 ition he had found in the red sandstone ; and while making his 

 ibservations, animals came along and actually walked over the 

 |:e, pressing it down on the mud beneath— breaking through and 

 jiaking tracks in the mud precisely similar in manner, &c., to the 

 vidences of bird tracks found by Prof. Hitchcock in the red sand- 

 one of the Connecticut valley, in such beautiful perfection Dr 

 .iarrett also said that he had carefully examined the sandstone used 

 |i the new library buihhng of Yale College, and he can show in 

 |ie cracks thereof evidences of the solar heat that produced them • 

 ')me of these had been partially filled up by sand and mud. He 

 Duld also show rain drops of the old world in this sandstone— 

 so the ripple marks of waves, and one triangular crystal of 

 bdstone. He could show where there were marks of the strong 

 aves and weak waves— wshoing very clearly that in that terribly 

 d world, water was subject to the same laws that it is now. 

 [The phenomenon referred to by Dr. Barrett furnishes no evi- 

 pnce of congelation— it is merely the effect of drying, or crys- 

 jlization. All rocks exhibit similar conditions.] — Ed. 

 jMr. Silliraan, jr., said that he thought the appearances spoken 

 by Dr. Barrett were attributable to the rhomboidhedral cleavage 

 often witnessed in the red sandstone, which had frequpntly been 

 ifearded as a species of semi-crystalization— little else than the 

 :^nted structure peculiar to the new red sandstone. 

 jProf. Johnson said that the remarks alluded to by Dr. Barrett 

 V^re very different from the jointed structure of the sandstone 

 s peculiarly noticeable in the pavements of the streets of Hart- 

 i'd. 



