Potomac and Rappahannock, which, besides being from sixty to seventy feet high over several miles, is in the main lithologically a perfect counterpart to many examples of the terrace at the same height on the British coasts. There are even more striking coincidences than these. The gravel plain at West Point, if it can be considered as connected with the sea margin of a former era, is in harmony with one of the greatest of the British terraces. Nay, among the elevated terraces which Mr. Roe has described as stretching along the sides of Lake Ontario, there are some which come surprisingly near to certain similar formations which others have described in this country. There may be nothing here but accidental coincidence; indeed it may be admitted that most probably there is nothing else in the case. It were well, nevertheless,

to make sure.

For this purpose, I now beg to suggest to the geologists of America, the propriety of examining such examples of ancient beaches as may be within reach in their several districts, with a view to settling the question one way or another. To all in America who have written on kindred subjects, I would respectfully recommend this inquiry, than which none could be more easily conducted. The first point should be, to find other instances of the sixty-four feet beach; in this country it is usually a broad terrace of sandy or gravelly materials, presented towards the sea or along the banks of tidal rivers. If really a general feature of America, as of Britain and Ireland, I should expect it to be found in many situations along the banks of the Hudson. An examination of the form and constitution of this terrace will fit the enquirer for discovering the higher beaches; to which, however, I do not think it proper to attempt affording any guide by the elevations of those found in Scotland, as obviously, if there be any correspondences these will have more force as evidence, if we can say that the two sets of facts were arrived at independently. I shall only remark that terraces between one hundred and fifty and three hundred feet are more likely to be efficient as tests than any of lower altitude excepting only the sixty-four feet beach, because in that higher range of elevations the intervals are wide and more characteristic. Accurate measurements by levelling from a certain specified datum are of course desirable, and the results should be published from time to time. I need scarcely say how much gratified I should feel by any communications to myself upon the subject.

ART. XXV.-Glycocoll (Gelatine Sugar) and some of its Products of Decomposition; by Prof. E. N. HORSFORD.

(Concluded from P. 70.)

PRODUCTS OF DECOMPOSITION OF GLYCOCOLL.

Action of Sulphuric Acid.

As glycocoll contains the elements of fumarate of ammonia, C. H, NO,, HO=NH, O,C, HỌ,,

4

4

4

it was conceivable that the employment of the appropriate agencies might effect a simple decomposition into these two members. Neither potash nor baryta, however, were found capable of expelling the ammonia. But upon dissolving in diluted sulphuric acid, and evaporation by heat to syrup consistence, redissolving with water, again evaporating, and repeating this process several times, at a certain stage, not definitely ascertained, the whole crystallizes in forms of great beauty;-which when washed with alcohol and pulverized, with addition of potash yield ammonia.

Some of the crystals were nearly cubic, reminding one of chlorid of sodium, others were rhombic with feathered margins. They taste and react acid, and do not change upon exposure to

the air.

Dried over sulphuric acid and analyzed, they gave the following results.

I. 0-4302 grm. of sub. gave II. 0.3526 66

III. 0.3574 66

IV. 0.4958

0.2031 carb. acid and 0.2099 water. 0-8062 platin-salammoniac.

แ

0-8300 platin-salammoniac.

Expressed in per cents.

0-6090 sulphate of baryta.

Sulph. acid,

These numbers give the formula:

C, H, NO, SO,, HO+NH,O, SO, HỌ,

as the juxtaposition of the per cents. of analysis and those de

rived from direct estimate will show:

This result supported the view that glycocoll contained not only the elements of fumaric acid and ammonia, but contained them in such form or arrangement, as would yield to an active affinity aided by heat.

It was highly probable, therefore, that galvanic action alone would be adequate to the task of decomposition.

To submit this query to the test of experiment, a solution of glycocoll was exposed to the action of a galvanic battery, consisting of four of Bunsen's pairs. The solution was separated by a membrane from the water. Upon closing the circle and plunging the poles terminated with platinum plate, one into the solution of glycocoll and the other into the water without, an instantaneous evolution of gas bubbles, at each pole succeded. After the action had continued a short time the fluid about the negative pole gave an alkaline reaction, while that about the positive pole gave an acid reaction. There could then scarcely a doubt remain, that glycocoll was a salt of which the base was ammonia and the acid a body identical in constitution with fumaric acid.

To obtain this acid, glycocoll was treated several hours, over a moderate heat with sulphuric acid, in the manner above described-repeatedly diluting and evaporating. The sulphuric acid for the most part was thrown down with oxyd of lead, and the last traces accurately removed with solution of baryta. The filtrate was then evaporated to concentration over sulphuric acid. In a few hours rhombic prisms of unexampled beauty and perfection, of the combination, P, OP, crystallized from the solution.

Their taste was exceedingly sour. In water they dissolved with difficulty and in ether and alcohol they were absolutely insoluble. With potash, ammonia was evolved from them.

Combustion with chromate of lead, gave the following results.
I. 0.1922 grm. of sub. gave 0·1048 carb. acid and 0.1008 water.
II. 0.2350 66
0.5700 platin-salammoniac.

or in per cent. :

Carbon,
Hydrogen,
Nitrogen,

15.28

With these results it was found impossible to construct any formula, containing only the elements of glycocoll, that could have been derived from the action of sulphuric acid. The first action of the acid would be the abstraction of ammonia.

C, H, NO, NH, C, H, O,.

4

5

4

4

If in excess it was conceivable that the remaining member would be subdivided, giving oxalic acid and an oxyd of the radical of Dumas' alcohol and ether series.

The latter uniting with sulphuric acid would give a compound that might not be thrown down by baryta and which with the ammonia, after the precipitation of oxalic acid would give—

C, H, O, SO,, NH, 0.

Upon heating the body with potash-dissolving in hydrochloric acid and adding baryta, a copious precipitate followed, establishing the presence of sulphuric acid. The small quantity prepared, prevented a determination of the quantity of acid. This formula requires 13-86 p. c. of carbon, 16-36 of nitrogen, and 6-81 p. c. of hydrogen.

It is not considered as established but merely as indicating approximately the action of sulphuric acid.

A concentrated solution of the crystals gave with baryta a crystalline precipitate that redissolved in hydrochloric acid.

With chlorid of calcium, upon the addition of ammonia, a crystalline precipitate was thrown down.

Want of time as well as of substance, postponed the further examination of this interesting body.

Action of Chlorine.*

When a moderately concentrated solution of glycocoll is subjected to a current of chlorine gas, the latter is rapidly absorbed, and an instantaneous and copious evolution of carbonic acid succeeds. Heat and sunlight both facilitate the action. A convenient method was found in connecting with a stream of dry chlorine gas, a Liebig's potash apparatus, filled, as far as is usual for a combustion, with a solution of glycocoll. It is only necessary that the rapidity of evolution equal that of absorption.

At the end of the third day the process was interrupted, and the liquid evaporated to a syrup consistence. A drop of this syrup yielded, upon the addition of ammonia, a white crystalline precipitate with both chlorids of barium and calcium.

Upon saturating with baryta, filtering and washing with absolute alcohol, it was found that but a small fraction of the glycocoll had been oxydated.

At

It was again returned to the potash apparatus, and exposed to a slow but uninterrupted stream of chlorine gas for a week. the conclusion of this period there was still glycocoll unchanged. Chlorid of barium gave the precipitate from the concentrated solution after neutralization with ammonia. This precipitate redissolved in water. It also redissolved in nitric acid, from which it was not thrown down by ammonia.

Mulder did not observe any action of chlorine upon glycocoll; a circumstance attributable possibly to the presence of an impurity rich in hydrogen, or to the action not being continued sufficiently long.

When washed and dried the baryta compound was no longer soluble in water, not even with long continued boiling. It was however promptly dissolved in dilute hydrochloric acid. It contains neither chlorine nor nitrogen.

The baryta salt alone was analyzed.

Combustion with chromate of lead gave from

I. 0-3218 grm. of sub. 0.1544 carb. acid and 0.0547 water. II. 0.6627 0.5210 sulphate of baryta.

The only formula which can be derived from these determinations is

The same remarks are applicable to this formula that have been made concerning the preceding.

It is recorded chiefly to show that chlorine does not act upon glycocoll as upon many other bodies, by which a certain number of atoms of hydrogen are replaced by an equal number of atoms of chlorine.

The action may be conceived to be the following:

4

3

4

C, H, No,+5HO+3C1=C, H ̧ O ̧+NH, Cl+Co2+2HCl. The same body was obtained by direct addition of a solution of permanganate of potassa to an aqueous solution of glycocoll. After boiling a length of time with nitric acid, the same product of decomposition was formed.

When pulverized chlorate of potash in small quantity and at intervals is added to a solution of glycocoll in hydrochloric acid, a slow oxydation goes forward, and a product is obtained, in which, as in the cases above noticed, baryta gives apparently the same white crystalline precipitate.

Action of Caustic Potash.

The brilliant fire red color assumed by glycocoll when heated with caustic potash, has already been noticed. If the solution be evaporated to extreme concentration, the evolution of ammonia and hydrogen continues, until at length the mass becomes solid. When treated with hydrochloric acid, hydrocyanic acid is evolved, and if iron salts be present Berlin blue is formed. When dissolved in water the addition of chlorid of calcium is followed by an instantaneous white precipitate, which does not dissolve in acetic acid-a precipitate of oxalate of lime.

SECOND SERIES, Vol. IV, No. 12.-Nov., 1847.

42