陶磁器原料の調合法は之を大別すれば乾式調合法と濕式調合法の2に分れる。而して乾式調合法は如何に努力しても原料の濕分に因る誤差を免れ難く結局調合は濕式法に依らなければならぬ。然し濕式調合法と雖も從來のボーメ比重計に依る定濃度體積調合法或は秤量に依り濃度を決定する秤量式定濃度體積調合法の如きはまだ多少の缺點がある。特にボーメ比重計は泥漿濃度の測定には適しない。
正確に近い調合を得るためには泥漿の體積計量と同時に其重量を計量する體積重量調合法に依らなければならぬ。調合すべき原料の乾燥重量と之を泥漿とした時の泥漿重量及其體積との間には次の如き關係式がある。
x-by+(b-a)c/a=0
茲にxは調合すべき原料の必要量を含める泥漿の重量, yは調合すべき原料の必要量を含める重量xなる泥漿の體積, aは調合すべき原料の比重, bは泥漿の温度に於ける水の比重, cは調合すべき原料の必要量 (原料の乾燥重量を以て表はす) である。
cは所定のものでありa,bも亦測定或は表に依て求めることが出來る。故に上式よりxyの關係を求むれば
dy/dx=1/b
表に依れば水の4-30℃間の比重の變化は42/10000でb≒1であるが故に此關係は直角座標にて表はせば軸と45°の角度をなす直線で表はされる。依て必要量の原料を含む泥漿の體積と重量の關係は簡單に見出される。而して式に明かなるが如く泥漿は濃度に支配されないが故に調合に際し濃度を一定にする必要もなく泥漿中の濃度分布を一様にする必要もない。且100メツシユ以下の粉末に於ては比重は實驗誤差範圍内の變化しか來さない故に原料の計量は粗碎粉末状態に於てなすも或は微細粉末状態に於てなすも變りなく何れを撰擇するも自由である。

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Continuing the previous study (This Journal, 1934, 42, 399), one of the present author S. Nagai carried on, in collaboration with Yoshio Kato, the studies on the relation between chemical compositions and water solubility or resistibility of window glass, chemical laboratory glass, industrial glass, etc. The main points of the present communication are briefly abstracted from the original Japanese paper, as following:
(1) Standard compositions of common soda-lime glass, i.e., SiO₂:72%, CaO:13% and Na₂O:15%, were changed in the amount of CaO, replacing by BaO, MgO or ZnO and fixing the amounts of SiO₂ and Na₂O nearly constant, as shown in the following table 1.
(2) These desired glass samples were prepared, by mixing the chemicals CaCO₃, Na₂CO₃, BaO, MgO, ZnO and pure silica sand, and melting the batches in chamotte crusible at 1400-1450°C of gas furnace. These glass samples were analysed and the following results were obtained, which were unfortunately a little deviated from the desired compositions shown in the table 1. The specific gravity of the. glass powder was also compared, and it was seen that BaO and ZnO increased the values of specific gravities and on the contrary MgO reduced the specific gravities.
(3) Various chemical glasses of beaker and flask and industrial glasses for the use of pressure gauge, were bought from the market, analysed and obtained the following results.
Among of these glasses high grade water resistibility can be obtained by increasing the amounts of SiO₂, B₂O₃, Al₂O₃, ZnO, Sb₂O₃ etc. and decreasing the amounts of CaO, K₂O, Na₂O, etc., from the following results of tests on water solubilities of these glass samples.
(4) These glass samples were crushed and sieved to grains, i.e., passing through 64 meshes/cm²-siev eand remaining on 144 meshes/cm²-sieve. These grains were throughly washed by absolute alcohol and completely dried in desiccator. The solubility of glass in water was tested in two ways.
I: The first method is to treat 5g of the above prepared glass grains and 200cc of distilled water in silver beaker for 2 hours on water bath.
II: The second is the autoclave method, i.e., 5g of glass grains was taken in silver crursible with 40cc distilled water and heated 2 hours in an autoclave under pressures of live steam of (1) 5 atm. and ca. 152°C, (2) 10 atm. and ca. 181°C, (3), 15 atm. and ca. 200°C, (4) 20 atm. and ca. 212°C, etc. After these heat tratments of both methods, the water was decanted and then titrated by 1/50-N-H₂SO₄ solution. The amount of titration in cc was a degree of solubility of glass alkalines. These both methods were already adopted in the first report and fully discussed (W. L. Baillie and F. E. Wilson: Journ. Soc. Chem. Ind., 1921, 40, 448 R; W. E. S. Turner: Journ. Soc Glass Tech., 1922, 6, 38, etc.). The results were fully compared in the following table 4.
From these results some important points were observed, i.e., (1) The alkaline earth component RO has the order ZnO>CaO>MgO>BaO of water resistibility of glass, (2) Among them ZnO is the most effective component to chemical and industrial glasses as seen by comparing the chemical analyses in the table 3 and the solubility tests in the above table 4 of glass samples of Flask II, Gauge Pipe I, II and III, and Gauge Prism, (3) These better glasses contain large amounts of B₂O₃ (6-8%), ZnO (4-6%) and Al₂O₃ (3-8%), and very small amount of CaO (1-3%), (4) Some glasses contain about 3.5% of Sb₂O₃, (5) Common window glass of soda lime glass type has smaller water resistibility than these chemical and industrial glasses, so that it must contain some other components

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1 カールバウム製最純炭酸石灰を900-1600℃で100℃おきに2時間加熱して生石灰を調製し, 其一定量をデュワー壜内の水中に投入して最高温度に達するまでの時間と上昇温度とを測定した。又生石灰の微構造及之に1-6倍の水を交ぜたものの變化を顯微鏡で觀測し, 且生石灰のX線寫眞を比較した。
2 水和の實驗では, 温度の上昇は燒成温度に關係なく, 最高温度に達する迄の時間も解離の不完全な900℃燒成物を除いては著しい差異を認めなかつた。此結果がK. W. Ray & F. C. Mathers氏 (Ind. Eng. Chem., 1928, 20, 415) 及其他の研究者の實驗結果と一致しなかつたのは是等の人々は石灰石を用ひたのに著者は純炭酸石灰を使用した爲であらう。
3 鏡檢の結果も燒成温度の影響が顯著でなく, X線分析の結果は1000-1600℃の燒成範圍に亙り全く同一であつた。

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