"These substances carry with them a degree of interest in another point of view. They seem to invalidate the opinion that the fetid smell of secondary limestone, slate, &c. is derived from the decomposition of animal matter. As their gangue is _decidedly_ a rock of primitive formation." _Another new mineral observed by Dr. Hayden._ "Exclusive of the interest which the necronite has excited with me and several others, I have besides stumbled upon another substance, if possible still more interesting. I discovered it in an imperfect state, about 4 years since, but not until recently have I been able to find it perfect, in beautiful garnet coloured cubic crystals ¼ of an inch square or nearly. These crystals are very liable or subject to decomposition, in which state they present a perfect but spongy cube. Although they resemble the cubic zeolite, yet they have nothing of its character with them besides." _Remark._ Dr. Hayden without doubt alludes to the _chabasie_ of the Abbé Haüy, formerly but inaccurately called the cubic zeolite; for it is really a rhomboid very nearly approaching a cube--its angles being 93° 48′, and 86° 12′. 5. PRESERVATION OF DEAD BODIES. _From Thenard's Chemistry_, vol. iii. _Paris ed. p._ 713. The author declines describing the methods of embalming commonly employed, and proceeds to describe the mode which was for the first time employed by Dr. Chaussier. "This process consists in placing the dead body thoroughly emptied and washed, in water kept constantly saturated with corrosive sublimate. This salt gradually combines with the flesh, gives it firmness, renders it imputrescible, and incapable of being attacked by insects and worms. "I have seen, (adds the author) a head thus prepared, which had been exposed alternately to the sun and rain during several years, without having suffered the slightest change. It was very little deformed, and easily recognized, although the flesh had become as hard as wood." 6. MATCHES KINDLING WITHOUT FIRE. (_From Thenard's Chemistry, Vol._ ii. _p._ 525.) This match is prepared by mingling two parts of the oxymuriate of potash and one of sulphur, which by means of a little gum is attached to a common sulphur match. This match on being dipped into, or rather slightly wet with, strong sulphuric acid, (oil of vitriol) immediately catches fire. The author has not added the caution that the sulphur and salt should be pulverized separately; if rubbed together in a mortar, they will explode with some danger to the operator, provided the quantity be over a few grains.