SUMMARY. The intricate and exact manner in which numerous and varied experimental facts have to fit in with one another for the demonstration of this proof of the structure of an atom of manganese makes it absolutely certain that the correct constitution has been obtained. A small portion only of this proof will now be considered, viz., the molecule MnO2 (No. 40), in order to make plain exactly what is implied by the frequent statement "corresponds with No. "X" in this and preceding papers. order that this statement may be justified, it is necessary that the following mathematical operations should have been successfully performed upon experimental data :

In

(E) Multiply this change of volume by the atomic weight 55 and also by 120, which is the constant for all elements of atomic weight greater than 22, to find the H.F. Result: -- 1254

This operation may be expressed as follows: Discover the Law of Heat of Formation.

(F) Find the equivalent original volume of an atom of oxygen. Result: -10.07. This is a difficult operation because the O-atom is solid in the molecule, but gaseous in the free state, so that latent heat has to be considered. The word " equialent" denotes that if the atom were solid in the free state its volume would have been 10.07.

66

(G) Subtract the combining volume 7.53 from the original volume 10.07. Result : 2.54.

(II)- Multiply this change of volume by the at. wt. 16 and also by 795, which is the constant for sub-sodium elements. Result: 32341

(I)-Subtract the combining volume 2.51 from 10.07. Result :- 7.56

(K) Multiply 7.56 by 16 and 795. Result :- 96155.

(L) Add together the three results of (E), (H) and (K) in order to obtain the H.F. of MnO2. Result :- 127242. Obs. 126000 and 125300. This result must be considered correct if it is within 2000 of the experimental result; because the experimental values for any particular substance frequently differ by more than 2000.

The fact that the original volume of Mn is 11.53 in three cases out of four makes it quite certain that there is no mistake for a reason exactly similar to that recently given in the summary of the paper on magnesium.

Each numbered line in this and all preceding papers contains a distinct numerical discovery.

ON ORGANIC COMPOUNDS OF
ARSENIC. PART II. REACTION
BETWEEN THE GRINGARD
REAGENT AND ARSENIC
TRIOXIDE.

By KAORU MATSUMIYA AND MINORU NAKAI.
ABSTACT.

The action of arsenic trioxide on the Grignard reagent was studied. On treating arsenic trioxide with phenylmagnesium bromide, triphenylarsine and diphenylarsine oxide were obtained; with p-tolymagnesium bromide, tri-p-tolylarsine and di-p-tolylarsine oxide were isolated; with a-naphthylmagnesium bromide, di-a-naphthylarsine oxide wre formed. On boiling the ethereal solution of methylmagnesium iodide with di-a-naphthylarsine oxide, methyl-di-a-naphthylarsine was produced. From these facts, the authors have come to the conclusion that Sachs and Kantarowitz's views about the reaction (Ber., 41, 2767( is incorrect, and that the reaction should rather be regarded as taking place according to the following equation:

=

As2O3+ 4RMgBr = (RAS),O+ 2MgO + 2MgBr.; (RAS) O+ 2RMgBr 2R,As + MgO + MgBr2.

10

The following compounds were isolated and examined di-a-naphthylarsine oxide [(C1H),As] O.H2O, white crystalline powder, M.P. 240-241°; di-a-naphthylarsine trichloride, (CH)AsCl, yellow crystalline powder; di-a-naphthylarsinic acid, (CH)ASO.OH, white amorphous powder, M.P. 228-229°; methyl-di-a-naphthylarsine, (CH) AS.CH,, colourless needles, M.P. 145-146°; and di-a-naphthylarsine oxychloride, [(C,,H,), AsCl2)]2O.

10

The melting points of p-tolylarsine compounds were found as follows: tri-p-tolylarsine 146-147°, di-p-tolylarsine oxide 105106 and di-p-tolylarsinic acid 173-174°. (Memoirs, College of Chemistry, Tokio University.)

Trade and General Notes.

REMOVAL OF FOREIGN LOANS
EMBARGO.

The Federation of British Industries desire to express their gratitude to the Government authorities of the country for the removal of the "embargo on the issue of foreign loans in this country.

They suggest, as preliminary steps, that His Majesty's Government should make it clear that no country with an unstable currency will be permitted to obtain any loan in the British market, except, of course, a loan contracted for the express purpose of currency stabilisation. They further consider that where countries with unstable currencies are indebted to Great Britain no arrangement concerning these debts which involves any concession to the debtors should be concluded until the most definite guarantees have been given by the government of the country concerned that they will stabilise their currency without delay.

INTERNATIONAL COMBUSTION, LTD. Messrs. International Combustion, Ltd., of Africa House, Kingsway, have informed us that their associated company of New York, the Combustion Engineering Corporation, received orders for the following plant during the month of September,

1925

Sir John Russell, director of the Rothamsted Station, said that in contemplating the decline of arable cultivation in this country in the last 60 years, the potato crop offered a ray of comfort. Its acreage had increased from 355,000 to 507,000, and its production from 2,750,000 tons to 4,000,000 tons. He uttered a warning against too rapid increase, however, in consequence of the fall in price resulting from a glut. In considering manuring,

three factors had to be borne in mind. In the first place it was essential that there should be sufficient air space and moisture in the soil to allow the tubers to grow. Secondly, disease was a more important factor for potatoes than any other crop; scab was associated with an alkaline soil, and blight with over-manuring with nitrogen and under-manuring with potash. In the third place, variety and climate set definite limits to yield. Farmyard manure should be the basis of all potato manuring, since it increased the air and moisture supply of the roots. It was best applied in the autumn, as it then had time to rot and supply this air and moisture in the spring. Trials were wanted, however, to determine relative values of autumn and spring applications. Investigations were proceeding with regard to the value of gree manuring as a substitute for dung.

As regards artificials, it could safely be said in general that 1 cwt. of sulphate f ammonia would increase the yield of potatoes by one ton per acre, at Rothamsted good returns had been received to applications as high as 3 cwt. Superphosphate improved the root action, but it was not essential for the English crop on all soils. An ample supply of potash was important for yield, health, and quality of crop. Sulphate of potash in general was better for quality than chloride of potash. Mr. J. C. Wallace, agricultural organiser

66

The foregoing definitions and standards are adopted as a guide for the officials of this department in the enforcement of the Federal food and drugs act.

for Holland (Lincs.), described his experiment on the silty 99 fen soil of that county, while Mr. R. W. Wheldon, of Armstrong College, Newcastle-on-Tyne, dealt with experiments at six centres in the North carried out by that college, chiefly as regards comparative effects of sulphates of ammonia and. potash on the one hand and chlorides on the other. The sulphates produced earlier and longer growth. He concluded that 3 cwt. sulphate of ammonia and 3 cwt. sulphate of potash could profitably be used in the North.

Mr. T. Eden, of the Rothamsted Station, spoke of the station's results. His general conclusions were that dung was beneficial to the yield, but not so much to quality, except where low-grade potash salts were included in the artificials; that potash paid well in most forms, except as very lowgrade salts; and that nitrogen always paid up to certain limits.

ALMOND PASTE AND KERNEL
PASTES.

FOOD INSPECTION DECISION 197,
(U.S.A., Department of Agriculture).

The following definitions and standards for almond paste and kernel pastes were adopted by the Joint Committee on Definitions and Standards, composed of representatives of the United States Department of Agriculture, the Association of American Dairy, Food and Drug Officials, and the Association of Official Agricultural Chemists, at its meeting July 13 to 17, 1925:

It con

Almond Paste is the plastic product obtained by cooking blanched and ground sweet almonds with blanched and ground bitter almonds, sugar, and water. tains not more than fourteen per cent. (14%) of water nor more than forty per cent. (40%) of total sugars expressed as invert sugar.

Kernel Pastes are the plastic products obtained by cooking, with sugar and water, the blanched and ground kernels of one or more of the following: Apricots, peaches, plums (prunes). They are free from hydrocyanic acid and contain more than fourteen per cent (14%) of water, nor more than forty per cent. (40%) of total sugars expressed as invert sugar. A kernel paste conforms in name to the kind or kinds of kernels employed in its production.

not