966 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [24] 
who breed oysters in this manner, cover their tiles with a slight coating 
of hydraulie cement. The young oyster attaches itself to the cement, 
but the coating, being very thin, is soon worn away, leaving the oyster 
quite firmly fixed to the tile. 
Others, on the contrary, who, six months after the collectors have 
been set, prefer to separate the oysters entirely from the tile, with the 
blade of a knife, generally cover the tile with two layers, and proc’ “i 
in a different manner. We cannot do better than to give their method 
of procedure in their own language: 
M. Eugtne Leroux says: “TI proeured some quicklime, which was 
slacked just as it was to be used, and was put, while still in a state of 
ebullition, into a large vat, where two-thirds the same quantity of sand 
had been placed. My men stirred the mixture, until it had attained the 
consistency of clear broth. The collectors had been made ready, and, 
held by the lower end, were dipped into the vat. One immersion suf- 
ficed, after which the women took them in hand-barrows and exposed 
them to the air to dry, before setting them up. ‘This excellent coating 
Should be prepared with fresh water only; sea-water prevents its ad- 
hering for any length of time to the tiles, and if it comes off the labor is, 
of course, lost.” 
M. Liazard states: “It was necessary to find a substance which, placed 
between the outer coating and the tile, would decompose, after remain- 
ing long in the water, and thus leave the coating almost free. I tried 
different pastes, all of which gave good results, but it was necessary to 
select the most economical. I was satisfied with a mixture made of flour 
and a small quantity of the scrapings of potatoes, boiled in a sufficient 
quantity of water to produce a thin paste. The tiles were dipped in 
this, and after they were dry they were passed through a bath of hy- 
draulic cement. Ihave always succeeded with thismixture; itis quickly 
made and costs but little. Every time I have neglected to use it I have 
regretted it.” 
M. Alphonse Martin says: “T first plunge each tile into a milk of 
quicklime, and when this coating is quite dry, I again dip the tile into a 
bath of hydraulic cement.” 
M. de Wolbock generally uses two layers of hydraulic cement. 
It seems to us rational that, when not intending to leave the oyster 
attached to the tile, we should resort to two layers, the first of quick- 
lime, which will not adhere very firmly, and the second of hydraulic ce- 
ment. The first facilitates the removal of the oyster and the second, the 
adherence of the young. 
Pursuing this idea, Dr. Kemmerer, in his report, makes the following 
proposition: 
“In oyster culture, not a single oyster should be lost. Ianticipate this 
result from the removable cement for collectors. Saturate your tile with 
water, cover the concave portion with wet paper, leaving the edges bare, 
then spread on the layer of cement, which must cover both the paper 
